Ea) of each stage was calculated using several nonisothermal kinetic methods, namely the ASTM E698, Kissinger–Akahira–Sunose, Starink, and Flynn–Wall–Ozawa methods. The Ea of pure MEA was 28.7 ± 2.5 kJ/mol, whereas that of the copper and zinc mixtures were 80.5 ± 1.1 and 46.8 ±1.7 kJ/mol, respectively. The results can be used to improve the intrinsic safety of storage tanks and petrochemical plants.Ethanolamine is a critical chemical for petrochemical enterprises. When corrosion occurs in pipelines, equipment, and containers in petrochemical enterprises, minute amounts of metal ions are released. In this study, the thermal decomposition and nonisothermal kinetics of monoethanolamine (MEA) and MEA mixed with copper and zinc ions were analyzed using thermogravimetry (TG) and differential scanning calorimetry (DSC). The TG tests revealed that MEA mixed with copper (II) and zinc (II) began thermal decomposition at 75.2 and 60.3 °C, respectively, whereas pure MEA began thermal decomposition at 89.7 °C. Two exothermic peaks were observed in the DSC curves for MEA mixed with copper (II) and zinc (II), and thermokinetic parameters were obtained from DSC data. The apparent activation energy ( Ethanolamine may also be used in desulfurization processes to remove acid gas and in the decarburization designs of refineries5. Ethanolamine is colorless, viscous, volatile, unstable, easily oxidized, corrosive6, and may cause fire or explosions when exposed to potent oxidants, such as hydrogen peroxide in a heated container7. Thermal decomposition and combustion may occur during the preparation, transportation, or storage of ethanolamine because of temperature imbalance and heat accumulation. At a company in Taoyuan, Taiwan in 2007, a fire and explosion occurred in a storage tank area containing 17 tanks of chemicals. The raw chemical materials involved in the accident primarily comprised glacial acetic acid, propylene glycol methyl ether, diethylene glycol butyl ether, and MEA.As a derivative of ethylene oxide, ethanolamine is a valuable product of amino alcohol consisting of monoethanolamine (MEA), diethanolamine (DEA), and triethanolamine (TEA). Ethanolamine may be used for a variety of applications, including use in the intermediates of pesticides8. Pipeline corrosion is a critical concern for petrochemical enterprises; long-term corrosion of pipelines may lead to leaks and ruptures. In such cases, fire or explosions will occur if a transported material is inflammable or explosive and encounters an effective ignition source. Additionally, pipeline corrosion releases metal ions with free radicals9, which causes catalytic decomposition reactions that play a critical role in chain reactions and result in exothermic events. Corroded pipelines have caused leakages, fires, and explosion accidents worldwide, resulting in considerable economic losses, negative social aftermath, and environmental hazards. The Kaohsiung gas explosion and Chevron refinery fire incident were caused by corroded pipelines and led to extensive economic, social, and environmental damages10.The petrochemical sector has begun to expand, and petrochemical facilities are connected by a multitude of pipelines. Common metal pipeline materials include copper, zinc, and iron6 investigated the thermal decomposition of MEA, DEA, TEA, and methyldiethanolamine (MDEA) and concluded that MEA exhibited the lowest thermal stability. In other studies, scholars12 have examined ethanolamine complexities using numerous methods, such as mixing ethanolamine with various oxidation states of vanadium. However, the thermal behavior of ethanolamine combined with metal ions has not been addressed in the literature; hence, the mechanism of metal ions in the thermal decomposition of ethanolamine should be determined.Generally, if corroded pipelines ethanolamine, the content of metal ions in the ethanolamine will increase gradually; the excess metal content then causes ethanolamine to foam and become unusable as a cleaning gas. Thus, the metal content of ethanolamine directly affects its quality and cost. More critically, this metal content provokes an incompatibility reaction, which induces advanced catalyzation of the material; consequently, the subsequent reaction cannot be controlled. ÁvilaHd), exothermic onset temperature (T0), and peak temperature (Tp)15, were obtained. The results revealed that the decomposition of MEA mixed with copper (II) and zinc (II) exhibited a reaction earlier than did the pure MEA. The apparent activation energy (Ea) of each stage was calculated using various thermokinetic models. The Ea of pure MEA was 28.7 ± 2.5 kJ/mol, whereas that of the copper and zinc mixtures were 80.5 ± 1.1 and 46.8 ± 1.7 kJ/mol, respectively. The results of this study may serve as a reference for the preparation, application, usage, storage, and disposal of MEA, and could be used to minimize thermal risk and enhance the intrinsic safety of storage tanks in petrochemical plants.The present study observed changes in the caloric value of MEA with the addition of various metal ions, namely copper (II) and zinc (II), by using thermogravimetry (TG), differential scanning calorimetry (DSC), and thermokinetic parameters, such as heat of decomposition . To prevent deterioration, all samples were stored in a dry and dark place.MEA of 99 mass% purity was purchased from Acros Organics . The chemical formula of MEA is C17. For pure MEA samples, the experimental temperature ranged from 30.0 to 300.0 °C and heating rates of 5.0, 10.0, 15.0, 20.0, and 25.0 °C/min were applied. In total, 10.0 mg of samples were used. Experiments using MEA mixed with CuBr2 and ZnBr2 were conducted at a heating rate of 10.0 °C/min within the temperature range of 30.0–650.0 °C. All samples were placed in a platinum crucible. Tests proceeded under an air atmosphere with 20.0 mL/min flow. Three sets of experiment were performed to ensure the reliability of the results and experimental methodology.TG experiments were performed using a Perkin Elmer Pyris 1 thermogravimetric analyzer  with a balanced furnace and vertical design. TG and differential TG (DTG) curves revealed variations in the mass loss and its derivative when the temperature was increased18. A DSC analysis was conducted to generate thermal curves denoting the temperature ranges of exothermic and endothermic reactions. Heat-flow data could be obtained from the area of the reactions19. The DSC-821 has been calibrated of heating rate at 4.0 °C/min before the experiment. In this study, DSC experiments were performed at heating rates of 2.0, 4.0, 6.0, 8.0, and 10.0 °C/min, and the test temperature range was set at 30.0–400.0 °C. STARe software was used to establish thermokinetic models and obtain kinetic parameters21. The sample sizes of MEA, MEA mixed with CuBr2, and MEA mixed with ZnBr2 were approximately 7.0 mg in each experiment. The sample ratio was approximately 2:1.Thermal analysis tests were performed using a Mettler Toledo DSC-821 . Because of its ease and efficiency of operation, DSC is the standard instrument used in conventional thermoanalysisEa was calculated in the nonisothermal experiment, which was performed in a growing environment. Kinetic analysis generally involves model-free and model-fitting methods22. The model-free method, also termed the isoconversional method, enhances analysis accuracy by excluding kinetic model functions25. In this method, the reaction rate is assumed to be only a function of temperature, and Ea values are compared at different conversions to corroborate the consistency of the reaction mechanism throughout the process26. Kinetic methods are divided into differential and integral methods27. In this study, the ASTM E698, Kissinger–Akahira–Sunose (KAS), Starink, and Flynn–Wall–Ozawa (FWO) methods were selected as representative methods for dynamic analysis. Table Ea. All of these methods were transformed using the nonisothermal kinetic equation, as presented in Eq.  was plotted against 1/T with a slope of −1.0037 Ea/RT to obtain Ea.The value of Ti), maximum decomposition temperature (Tm), and final decomposition temperature (Tf) all increased, as did the rate of mass loss, which reached 7.4%/min at a heating rate of 25.0 °C/min. The decomposition of all heating rates was complete without residues before the temperature reached 200.0 °C.Figure 2 and ZnBr2 at a heating rate of 10.0 °C/min in an air atmosphere are presented in Fig. 2 consists of three stages. The first stage, which occurred between 50.0 and 230.0 °C with a mass loss of 78.3%, was attributed to the reaction of MEA and CuBr2. The second stage, which occurred between 230.0 and 450.0 °C with a mass loss of 6.9%, represented the decomposition of the remaining CuBr2. The third stage, which occurred between 450.0 and 700.0 °C, resulted in the formation of 5.6% of residues and corresponded to the formation of CuO. For MEA mixed with ZnBr2, the TG and DTG curves indicated two stages of mass loss. The first decomposition (30.0–200.0 °C) resulted in 60.0% mass loss and was caused by the reaction of MEA and ZnBr2. The mass loss (40.0%) of the second decomposition (at 200.0–700.0 °C) was caused by the decomposition of the remaining ZnBr2 without residues’ formation.The TG and DTG curves of MEA and MEA individually mixed with CuBrTi and Tm decreased in the first stage. As indicated in Table Ti = 60.3 °C) catalyzed the reaction of MEA more quickly than did the addition of copper (II) (Ti = 75.2 °C).The calculated values of TG and DTG for various stages of the three samples are presented in Table T0) and maximum decomposition temperature (Tp) were 89.5 and 130.3 °C, respectively. T0 can be defined by the intersection of a line drawn tangent to the steepest slope of the curve with the baseline; moreover, Tp is the maximum exothermic temperature that can be achieved in the exothermic interval. The curves of MEA mixed with CuBr2 and MEA mixed with ZnBr2 produced two exothermic peaks at approximately 120.0 and 320.0 °C, respectively. The first peak indicated that advanced canalization occurred after the addition of CuBr2 and ZnBr2 to MEA. T0 decreased to 79.2 and 69.6 °C, respectively, which is consistent with the results of the TG test, and Tp decreased to 117.6 and 110.5 °C, respectively. ΔHd was similar in the first peak for all three samples, namely 185.4, 199.6, and 151.6 J/g, respectively. For the second exothermic peak of MEA mixed with CuBr2 and ZnBr2, the respective values of Tp were 322.8 and 316.7 °C. The peak may be considered representative of the thermal decomposition of the remaining bromide. In this test, the influence of Br− in the decomposition of MEA could be disregarded because both metallic compounds contained negative ions.The DSC curves of the three samples at a heating rate of 8.0 °C/min are displayed in Fig. 2 and (b) ZnBr2 at heating rates of 2.0, 4.0, 6.0, 8.0, and 10.0 °C/min. The DSC curves exhibited similar trends. The exothermic intervals of the first and second peaks were 50.0–180.0 and 200.0–380.0 °C, respectively, and T0 and Tp were delayed as the heating rates increased. For MEA mixed with ZnBr2 in the DSC experiments, regularity among T01, Tp1, and ΔHd1 with the increasing heating rates in the first peak could not be confirmed, as indicated in Fig. 2, which rendered the initial reaction unstable. However, the values of ΔHd in the second peak at different heating rates were between 99.5 and 124.7 J/g. For MEA mixed with CuBr2, the ΔHd results of the first and second peaks at five heating rates were 187.4–237.8 and 373.6–471.9 J/g, respectively. All thermokinetic parameter results are listed in Table Figure Ea is a crucial kinetic parameter for evaluating the reactability of a substance. To further explore the effects of adding copper (II) and zinc (II) on the thermal stability of MEA, various nonisothermal kinetic methods were used to analyze the exothermic peaks in the DSC tests. Ea results were calculated for MEA and MEA mixtures at each experimental stage.Ea of each set of experiments. Figure Tp for the four exothermic peaks according to the ASTM E698 method. The Ea results for the first and second peaks of MEA mixed with CuBr2 were 30.3 and 115.6 kJ/mol, and those for MEA mixed with ZnBr2 were 42.1 and 116.9 kJ/mol, respectively. However, the ASTM E698 method could not be used to reveal the overall trend of Ea at each conversion. The values for Ea acquired using the ASTM E698 method were slightly inaccurate for these experiments because of the basic assumptions of the method28. Subsequently, the KAS, Starink, and FWO methods were used for different conversions. The DSC curve exhibited artificiality in baseline selection during processing and analysis, especially for reactions at the beginning and end with device noise. Therefore, the conversion at the interval of α between 0.1 and 0.9 was selected for the kinetic analysis.The ASTM E698 was first used to calculate the Ea values can be identified at different conversions. Plots for the first peak of MEA mixed with ZnBr2 obtained using these three methods at different conversions are displayed in Fig. Ea was calculated within the interval of 0.3–0.7, as suggested in relevant studies29. The plots of other peaks that are not displayed in Fig. Ea was readily calculated at different conversions using the slope of the curves in Fig. Ea of MEA mixed with CuBr2 and ZnBr2 at different conversions. The variation of Ea at different conversions for these four exothermic peaks according to the KAS, Starink, and FWO methods is represented in Fig. Ea were obtained with the KAS and Starink methods, whereas the FWO method yielded a slightly higher Ea value.For the KAS, Starink, and FWO methods, general trends in Ea and R2 for each nonisothermal method. The Ea of pure MEA was 28.7 ± 2.5 kJ/mol, which is lower than the value indicated in related studies6. For MEA mixed with CuBr2, the Ea of the first peak was 80.5 ± 1.1 kJ/mol, suggesting that the Ea of the mixture was higher than that of pure MEA. The data listed in Table Ea increased with conversion; this was likely because of a chemical reaction and the formation of a copper-alkanolamine complex30. The calculated value of Ea in the second stage was 125.9 ± 1.5 kJ/mol, which was slightly higher than the value reported in a relevant study31. This value may be attributable to the decomposition of the remaining CuBr2. For MEA mixed with ZnBr2, the Ea values of the first and second peaks were 46.8 ± 1.7 and 113.6 ± 1.9 kJ/mol, respectively. As indicated by the R2 values in Table 32.Table 2 and ZnBr2 began at 75.2 and 60.3 °C, respectively; all mixtures produced prior decomposition reactions compared with pure MEA (89.7 °C).In this study, the thermal decomposition and nonisothermal kinetics of pure MEA and MEA mixed with copper (II) and zinc (II) were illustrated using TG and DSC. In the TG tests, the thermal decomposition of MEA mixed with CuBr2 and ZnBr2 to MEA. Although no notable change in ΔHd occurred, T0 decomposed early at 79.2 and 69.6 °C in the copper and zinc mixtures, respectively. These results suggested that metal ions may provoke early reactions during the manufacturing process. These advanced reactions may lead to thermal decomposition of the material of interest at low temperatures, resulting in thermal hazards. Moreover, nonisothermal methods, namely the ASTM E698, KAS, Starink, and FWO methods, were used to analyze the decomposition kinetics of MEA and MEA mixtures. The fitting was insufficient in a single conversion compared with the R2 in different conversions. The Ea of pure MEA was 28.7 ± 2.5 kJ/mol. The Ea results of the copper and zinc mixtures were 80.5 ± 1.1 and 46.8 ± 1.7 kJ/mol, respectively. Chemical reactions caused by the addition of metal ions resulted in these results of higher Ea for the mixtures.In the DSC analysis, two exothermic peaks were observed after the addition of CuBrEthanolamine is widely used in petrochemical industries, and the operation of such enterprises involves numerous unsafe processes. Because of the advanced reactions of metal ions to ethanolamine, corroded pipelines and equipment should be promptly replaced to reduce the likelihood of chemical disasters and ensure plant safety.


Viburnum opulus (VO). Antioxidant capacity was evaluated against ABTS, hydroxyl, peroxyl and superoxide free radicals, and as a reducing power by using in vitro test. The results showed great quantitative differences in the composition of the VO morphological parts tested. Fruits contained the highest concentrations of fat, organic acids, sugars, soluble dietary fiber  and carotenoids (2.70 ± 0.07 mg/100 g DW). Whereas, the bark exceeded the remaining parts of the VO in terms of antioxidant capacity, ash (9.32 ± 0.17 g/100 g DW), total (59.34 ± 0.75 g/100 g DW) and insoluble dietary fiber (58.20 ± 0.73 g/100 g DW) contents as well as phenolic compounds (3.98 ± 0.04 g/100 g DW). Among the phenolic compounds quantified in this study, chlorogenic acid and (+)-catechin had the highest concentrations (> 1 g/100 g DW) in the flowers and bark, respectively.In this work, the profiles of phenolics, fiber, pectins, sugars, organic acids and carotenoids, vitamin C, ash, protein and fat contents, as well as antioxidant capacity were compared in fruits, flowers, and bark of The online version of this article (10.1007/s11130-019-00759-1) contains supplementary material, which is available to authorized users. Viburnum opulus L. (Adoxaceae), commonly known as European guelder, is also called as European cranberrybush, guelder rose, wild guelder rose, cherry-wood, rose elder, crampbark tree and snowball bush, and gilaburu in Turkey [Viburnum opulus (VO) is a valuable decorative, medicinal and food plant. In Russia, Ukraine and among many Siberian nations the VO fruits, despite their astringent-bitter-sour taste, are used in traditional cuisine as a component of marmalades, jams, cordials and liqueurs, and “Kalinnikov” pies as well as herbal teas [n Turkey –3. It isn Turkey , 4. Vibubal teas . Also, ibal teas .in vitro studies demonstrated the antioxidant properties of VO fruit, branch, leaf and bark extracts [V. opulus result from the presence of bioactive components in the plant, such as phenolic compounds, vitamin C, carotenoids, triterpenes, iridoids, essential oils, saponins and dietary fiber [The VO fruits and fruit juice have been used to treat a wide range of illnesses, including bleeding, heart disease, high blood pressure, coughs and cold, neurosis and diabetes , 7–9. Inextracts –16. Healry fiber , 16–18. ry fiber .So far, most of the research have been carried out to characterize the chemical composition of VO fruit and fruit juice. However, there is no information or little is known about the chemical characteristic of other parts of the plant for which health-promoting effects have also been demonstrated. The aim of this study is to compare the biochemical components and antioxidant potential of poorly described flowers and bark with well known fruits of VO to recommend the use of the most valuable VO parts in pharmaceutics, cosmetics and/or functional foods.The material and methods section is presented as supplementary material p < 0.05) between VO fruits, bark and flowers in terms of protein, ash, organic acids, sugars, dietary fiber and pectin contents were observed. The fruit of VO was characterized by the significantly highest content of fat (10.57 g/100 g DW), total organic acids (7.34 g/100 g DW) and total sugars (32.27 g/100 g DW) as well as the lowest concentration of ash (2.96 g/100 g DW) and total fiber (38.44 g/100 g DW). Meanwhile, the flower of VO was the richest in protein and pectins . Among three VO anatomical parts tested bark had the highest content of ash (9.32 g/100 g DW) and total fiber (59.34 g/100 g DW). In the fresh VO fruits grown in Turkey the ratio of protein to ash was 1.8 and it was consistent with the value calculated for the VO dried fruit tested in this work [Quercus faginea bark in comparison to our result for VO bark.To our best knowledge, there are no reports on the basic chemical composition of VO bark and flowers. However, the content of macronutrients in VO fruits was previously analyzed by other authors , 18–20. his work . Whereashis work . On the his work  obtainedThe results obtained for the sugars analysis are shown in Table Data in Table The content and composition of soluble (SDF) and insoluble (IDF) dietary fiber fractions varied with parts of VO plant tested Table . The totp < 0.05) between VO dried fruits, bark and flowers in terms of total phenolics, flavonoids and proanthocyanidins were observed. Carotenoid content was the highest in VO fruits and similar in bark and flowers. The commercially available VO bark was characterized by the highest level of total phenolics, flavonoids and proanthocyanidins as compared to other parts of plant. Contrary, in none of the tested VO parts was found L-ascorbic acid. According to the literature, the concentration of ascorbic acid and carotenoids in fresh VO fruits was in the range 12.4–164.0 mg and 1.4–2.8 mg per 100 g fresh weight (FW) [The contribution of plant-derived compounds to health improvement has been partly attributed to their antioxidant capacity. The natural plant antioxidants are mainly phenolic compounds, carotenoids, and vitamins C and E. A study was therefore undertaken to determine these phytocompounds contents in VO commercial products tested Table . The staght (FW) . Comparight (FW)  in the rper 100 g FW according to colorimetric assay [The obtained results showed that the content of total phenolics in VO different morphological parts was in the range of 3.51–3.98 g/100 g DW and significantly exceeded the concentration of carotenoids. For comparison, the content of phenolics was estimated at 0.68–0.83 g/100 g FW of VO fruits grown in Czech Republic and 0.40–0.73 g/100 g FW of fruits from Russia . Total pic assay , and froic assay  have shop-hydroxybenzoic and gallic [p-hydroxybenzoic and caffeic acids, these compounds have not been detected in dried VO bark. In the present study, a comparison of the retention time and UV-Vis absorption spectra to those of the reference compounds allowed us to determine four flavanols and four hydroxycinnamic acids in VO bark with (+)-catechin as dominated phenolic compounds (1062.43 mg/100 g DW) followed by procyanidin B1 (437.79 mg/100 g DW) and chlorogenic acid (352.49 mg/100 g DW). We provide the first report on the flavanols composition in VO bark.Data on the composition of individual phenolic compounds are very important because the structure of phenolics significantly affects their properties. In connection with the above, the ethanolic extracts of VO fruits, flowers and bark were analyzed for the content of individual phenolic compounds using UPLC system. The results of qualitative and quantitative phenolic composition in VO samples are summarized in Table d gallic . AlthougRegarding the most studied phenolic profile of VO fruit, hydroxybenzoic and hydroxycinnamic acids, catechins and procyanidins as well as flavonols and anthocyanins were identified by HPLC-MS-TOF and HPLC methods , 3, 5. HThere are no previous studies and references on the phenolics composition of the VO flowers. We report here the first UPLC profile of VO flowers. According to our data, flowers were more abundant in hydroxycinnamic acids, flavonols, and flavanols compared to fruits. The main phenolic compounds in flowers was chlorogenic acid (1535.42 mg/100 g DW) followed by isorhamnetin (58.84 mg/100 g DW), isorhamnetin 3-glucoside (47.06 mg/100 g DW), and (+)-catechin (46.87 mg/100 g DW).•+ radical cation (ABTS) and toward reactive oxygen species such as •OH radical (HORS), O2•- superoxide anion radical (SORS), peroxyl radical (ORAC) and as the potential to reduce ferric to ferrous ion (FRAP). Trolox – a water-soluble analog of vitamin E, was used as an antioxidant standard to determine the Trolox equivalent (TE). Exceptionally, (+)-catechin was used as the antioxidant standard in the SORS assay to determine the catechin equivalent (CE). The higher TE and CE values, the greater the antioxidant potential. The results for antioxidant capacity of VO natural antioxidants, extractable by 70% ethanol, are presented in Table p < 0.05) were found among the analyzed parts of VO in the antioxidant capacity, except VO flowers and fruits in SORS assay. The TE values varied from 16.18 to 40.21 mM/100 g DW of product in ABTS assay, from 5.91 to 10.05 mM/100 g DW in HORS method, from 10.93 to 108.17 mM/100 g DW in ORAC assay, and in the range 13.65–23.47 mM/100 g DW in FRAP method. Antioxidant potential of VO products in SORS assay as CE ranged between 89.77 and 115.44 mM/100 g DW of product. The antioxidant capacity of VO different parts investigated was in the following order in HORS, SORS and ORAC assays: bark > flowers > fruits and the order in ABTS and FRAP assays was bark > fruits > flowers. The values obtained clearly reflect that the VO bark components showed the greatest antioxidant capacity, regardless of the method used. The scavenging effect of VO fruit components on ABTS•+, DPPH• , •OH, O2•- and NO• (nitric oxide) radicals are reported in the literature [2•- radical was lower than VO branch and leaf activities but higher than VO leaf activity in DPPH assay [r ≥ 0.97). Correlation analysis also evidenced a positive relationship between the total phenolic, flavonoid and proanthocyanidin contents with SORS test (r ≥ 0.78). On the other hand, the Pearson’s coefficients listed in Table The use of plants rich in antioxidants can prevent or delay the development of non-communicable diseases through processes involving reactive oxygen species. In biological system, reactive oxygen species, such as superoxide, hydroxyl radicals, can damage the DNA and lead to the oxidation of cellular lipid and proteins . Antioxiterature . Rop et PH assay  using thPH assay . CorrelaViburnum opulus (VO) which are commercially available in Poland. This is the first detailed report on the phytochemicals and antioxidant properties of VO flowers as well as on the macronutrients in VO bark. The results demonstrated the differences in the basic chemical and bioactive compounds composition, and antioxidant properties of different morphological parts of VO. Bark constituents were the most active against free radicals, which was consistent with its highest phenolic compounds contents, especially proanthocyanidins and flavanol monomers. In addition, our results indicate that VO bark and flowers have high commercial potential due to their higher dietary fibre and phenolics contents, and lower sugars concentration in comparison to VO fruits. Taking into account numerous published data on the relationship between the biological activity, especially antioxidant properties, and the content of phenolic compounds for future studies, it is necessary to investigate the phenolic compound profile of VO bark and flowers using mass spectrometry method.In conclusion, this research has comprehensively investigated the chemical composition and antioxidant capacity of different parts  of ESM 1(DOCX 26 kb)


Hirschmanniella anchoryzae from Iran and Pratylenchus hippeastri from South Africa were recovered during a survey of plant-parasitic nematodes belonging to the family Pratylenchidae. Both species were studied using morphological and molecular techniques. Hirschmanniella anchoryzae is identified based on the flattened head, short stylet (19–22 µm), excretory pore position , spicule length (27–30 µm), and existence of an axial mucro at the tail end. Phylogenetic analysis using 28S rDNA showed monophyly of Hirschmanniella which Iranian H. anchoryzae placed close to H. halophila . This result was supported by the principal component analysis of Hirschmanniella species. SEM observation of the South African population of P. hippeastri showed the presence of two annuli in the lip region. Morphometric characters resembled those of specimens earlier reported from South Africa. Hierarchal cluster using morphometrical criteria showed that the Floridian (USA) and South African populations form a group. However, the principal component analysis showed variation within this species. The molecular study of P. hippeastri populations using 18S, ITS, 28S rDNA, and COI of mtDNA showed that all P. hippeastri cluster in one group and confirmed the identification of the species using both morphological and molecular techniques. In addition, the results indicated that South African populations group close to the USA populations. Illustrations of both species including light and scanning electron microscopy observations for P. hippeastri are provided. Hirschmanniella has been established by Hirschmanniella, namely, H. anchoryzae . The root-lesion nematodes belong to the family Pratylenchidae and cause severe damage on various crops and yield reduction . The genchoryzae , H. gracgracilis , and H. . oryzae , and witrom Iran . Those srom Iran . Root-leylenchus , are aftylenchus . PratyleHischmanniella and P. hippeastri using morphology, morphometrics, and molecular DNA barcoding; (ii) to study of morphological variations among different P. hippeastri populations, and (iii) to determine the phylogenetic position of H. anchoryzae from Iran using 28S rDNA and P. hippeastri from South Africa using rDNA and mtDNA genes.The main objectives of the present study were to (i) to identify the populations of Hirschmanniella specimens were collected from the rhizosphere of Mentha aquatica in Royan  and Pratylenchus specimens were collected from rhizosphere soil samples of Cape Willow trees  growing on the banks of the Mooiriver in Potchefstroom  and extracted from soil using the Whitehead tray method , body length, stylet length, pharynx length, tail length, and position of the excretory pore were used for PCA analysis of Hirschmanniella. The species, namely, H. halophila , body length, pharynx overlapping , stylet length, DGO, MB (middle of metacorpus to anterior end), post vulva sac length, tail length, and position of the phasmid , and ddH2O for a final volume of 30 µl. The amplification was processed using an Eppendorf master cycler gradient , with the following program: initial denaturation for 3 min at 94°C, 37 cycles of denaturation for 45 sec at 94°C; 54°C, 55°C, 56°C, and 52°C annealing temperatures for 18S, ITS, 28S rDNA, and COI of mtDNA, respectively; extension for 45 sec to 1 min at 72°C, and finally an extension step of 6 min at 72°C followed by a temperature on hold at 4°C. Regarding Hirschmanniella only 28S rDNA and COI of mtDNA have been used for DNA amplification. After DNA amplification, 4 µl of product from each tube was loaded on a 1% agarose gel in TBE buffer  for evaluation of the DNA bands. The bands were stained with RedGel (ethidium bromide for the Iranian specimens) and visualized and photographed on a UV transilluminator. The amplicons of each gene were stored at –20°C. Finally, the PCR products were purified for sequencing by Inqaba Biotech (South Africa) and Pishgam (Iran) for the Iranian specimens. Available sequences for other Hirschmanniella and Pratylenchus spp. were obtained from NCBI GenBank for comparison (Table Pratylenchus vlunus (EU130885) for Hirschmanniella based on the study of Zygotylenchus guevarai  is at 3 to 4 µm posterior to stylet base; median bulb is spherical to oval with 7 to 11×9 to 10 µm length and width, respectively; nerve ring is located just after isthmus, at 27 to 28% of the neck ; excretory pores are at 1 to 8 µm anterior to the pharyngeal-intestinal junction, at 35 to 37% of the neck; hemizonid is 5 to 8 µm anterior to excretory pore; pharyngeal glands are overlapped with 8 to 10 times than the corresponding body diameter; pharynx is 380 to 410 µm long, about 22% of the body length; in reproductive system didelphic amphidelphic, ovary is not reaching the pharyngeal glands; oocytes are in one or two rows; vulva occupies 35 to 40% of the corresponding body diameter; spermatheca is visible, oval shape, with sperm; vulva is with a transverse slit with not protruded lips, V = 53 to 57; tail is 96 to 106 µm long, conical, elongated with 63 to 80 ventral annuli and axial mucro, in some specimens the appendage visible as a notch; and phasmid is located at about middle of the tail, 57 to 61% of the tail length.The description of female body of The structure of male body is similar to the female body with hypoptygma. Reproductive system is monorchid. Spicules tylenchoidis of 30 to 35 µm length, paired, separate in ventral view, smooth, and ventrally arcuate in lateral view; rounded manubrium; calamus very short, lamina thin, ventral curved end. In lateral view, the gubernaculum is bent, 5 to 8 µm length, 18 to 26% of spicule length. Bursa is leptoderan. Phasmid is 60 to 70% of the tail length. Tail is conical, elongated, 81 to 87 µm with axial mucro at tail tip.Hirschmanniella is similar to H. anchoryzae based on the original description and the identification key  in a good state of preservation were studied. Iranian population of tion key . In comprom Iran , they di. oryzae  in havin. oryzae . This pogracilis . Howevergracilis .H. anchoryzae  of H. halophila , our sequence showed 84% identity with 61 nucleotide differences, whereas another population of H. mucronata (KR819278) from China there was 71% identity with 89 nucleotide differences. Genetic pairwise distance (Table H. anchoryzae (MK571451), obtained from H. halophila  and H. mucronata , respectively. The lowest range (0.000) was observed between an unidentified Hirschmanniella (DQ328686) from Vietnam and H. oryzae from Myanmar and the Philippines.The genes 28S rDNA and COI of mtDNA for alophila  with 35 Hirschmanniella species  H. loofi, H. kwazuna, H. mucronata, and unidentified Hirschamnniella with 1.00 posterior probability, and (iii) H. anchoryzae, H. pomponiensis, H. santarosae, and H. halophila with 1.00 posterior probability.The Bayesian inference tree of 28S rDNA of ies Fig.  grouped H. belli , and uniFigs. ; Table 3Pratylenchus hippeastri: body length is 423 to 614 µm, slightly curved after fixation, some specimens straight; cuticle is finely annulated with 0.9 to 1.2 µm wide at midbody; maximum body diameter is 17 to 27 µm; cephalic region is continuous with the body; lip region is round to flat, with a slight depression, bearing two annuli; lateral field with four lines, started with two lines 7.5 µm from anterior end, ending at tail terminus with three lines, occupies about 25 to 36% of midbody diameter and around 53% at the vulval region; stylet length is 13.3 to 18.0 µm, basal knobs usually rounded and flatted; dorsal esophageal gland opening (DGO) is at 1.7 to 3.6 µm posterior to stylet base; median bulb oval, nerve ring located just after isthmus, is at 48 to 66% of the neck; excretory pore is at 80 to 112 µm from the anterior body, at 60 to 70% of the neck; hemizonid one annuli is anterior to excretory pore; pharyngeal glands overlapped with intestine are about 32 to 43 µm; neck is 116 to 149 µm long, body length about 3.5 to 4.9 times than pharynx length; ovary is not reaching the pharyngeal glands; columnar cells of uterus are distinct and disposed in four rows; oocytes are in one row at growth zone (V = 75-82); spermatheca is visible, circular to oval shape, without sperm; post-vulval uterine sac is 11 to 26 µm long, vulva with a transverse slit and protruded lips; tail is conoid with bluntly pointed, usually with a ventral constriction at the middle or subhemispherical, slightly smooth terminus; tail is with slightly indented terminus observed in some specimens; tail is 26 to 43 µm long, about 2.0 to 2.5 times than anal body diameter; phasmid is located at about middle of the tail, 46 to 55% of the tail length; and the hyaline portion of tail terminus is 2.5 to 3.8 µm long.The description of female body of Not found.P. hippeastri. SEM observation of the Potchefstroom individuals indicated that two lip annuli are present, in which the first one being deeper. Uncompleted lip annuli and tail variation forms were not observed in Potchefstroom specimens. According to the identification key presented by P. hippeastri is similar to P. scribneri Steiner in P. hippeastri from P. scribneri by a longer tail (36.6 vs 26.7 μm), slightly longer stylet (15.4 vs 14.7 μm), and shape of tail terminus, but often bluntly pointed and smooth terminus vs the consistently hemispherical and smooth tail terminus. The present results indicated that the stylet is overlapped in the two mentioned species (stylet length 13.3-15.4 µm in South African population in this study). Concerning the tail end morphology, none of the South African specimens studied had smooth ends. Hence, based on the results of this study, the tail morphology of P. hippeastri seems to be different from that of P. scribneri as shown in the study of Seven females from Potchefstroom (South Africa) in a good state of preservation were studied. This species was previously reported from Florida, USA , Japan , and ChiP. hippeastri populations studied showed that some morphometric data, obtained from 63 females , showed significant correlations with others. Some important morphometric data such as body length seemed to be considered to understand the correlation with each other. Results indicated that body length showed the highest correlation with the b (r = 0.786) and tail (r = 0.768), respectively (Table r = 0.277). Despite the stylet length, body length showed the highest significant correlation  with MB (median bulb to anterior end as % of the pharynx). Tail length showed a highly significant correlation with the index b (r = 0.904).The results based on two-tailed Pearson correlation within the five ly Table . On the P. hippeastri  and South Africa with 100 (AU: approximately unbiased) values and the second group consisted of populations from China and Japan with 100AU values  is similar to those of populations from the Israel and China  with three and five nucleotide difference, respectively. In addition, it is similar to a Dutch population of P. scribneri  with two nucleotide differences. The ITS rDNA of the population studied (MH324471) is similar to those of populations from the USA . Compared to the Chinese population of the same species, the Potchefstroom population showed two nucleotide differences . The 28S rDNA of the population studied  are similar with populations from the USA  and China , with one and two nucleotide difference, respectively. The COI gene of mtDNA of the population studied (MH324474) is similar to those of populations from China , with 11 and 10 nucleotide differences, respectively.The 18S rDNA (859 bp), ITS rDNA (910 bp), 28S rRNA (707 and 713 bp), and COI (mtDNA) (382 bp) gene fragments of the P. hippeastri, the Bayesian inference trees constructed on the basis of the 18S rDNA, ITS rDNA, D2 to D3 segment of 28S and COI of mtDNA sequences are shown in Figures P. hippeastri are placed in one group with highly supported bootstrap values of 100%. Based on the phylogenetic analysis using ITS  as well as P. scribneri Steiner inP. araucensis .According to the 28S rDNA phylogenetic tree results Fig. , the Souaucensis  from Geraucensis  indicateHirschmanniella comprises 24 nominal species according to Hirschmanniella mucronata was a sister taxon to H. kwazuna and H. loofi, with strong support as stated by Hirschmanniella oryzae and H. belli also form a group, which is stated by H. belli vs 1.03-1.63 mm in female and 1.01-1.40 mm in male for H. oryzae), stylet length (20-22 µm for H. belli vs 15-19 µm for H. oryzae), and spicule length (31-36 µm for H. belli vs 18-26 µm for H. oryzae)  and male (present vs absent). In comparison with H. pomponiensis, they differ in female body length (1.7-1.9 mm vs 1.7–2.4 mm), tail length , spicule length (27–30 µm vs 32–40 µm) and gubernaculum length (8.6–8.7 µm vs 10–13 µm). In comparison with H. halophila, they differ in lower value of the body (1740 µm vs 1260 µm) and mucro at tail tip (1 vs 2-4). The placement of the species based on 28S rDNA is in agreement by the PCA analysis which H. anchoryzae and H. halophila place close each other.The genus  oryzae) . The phyP. hippeastri, is suitable to find variation among populations. In addition, morphometric cluster analysis is also suggested that the variation among the P. hippeastri specimens as the South African and the USA populations were placed together, while the Chinese and Japanese populations group together, both with 100 bootstrap values.The usefulness of morphometric analyses, due to significant correlations between some morphometric characteristics of females of the five populations of P. thornei.Pratylenchus. However, the mentioned author did not report any correlation that possibly exists in the genus Pratylenchus. In our study, the body length showed correlation with the post uterine sac and tail, as well as the indices such as b′, which agreed with those reported by P. thornei. Furthermore, P. coffeae from Vietnam by using five morphometric characters of the male specimens successfully, representing of the usefulness of morphometric analysis among the specific species of Pratylenchus. Concerning to other plant-parasitic nematodes, a, c, and c’ are often useful to accurately identify species of Helicotylenchus (a and b) showed a high correlation to each other for Hirschmanniella belli. H. avenae group. As a result of this study, cluster analysis, according to morphometric characteristics, grouped the South African population of P. hippeastri close to the American populations, but in a separate group than the Asian populations.Regarding morphometric analysis, the correlations of such measurements or indices have been studied by ylenchus . FortuneP. hippeastri was studied by the use of rDNA  and mtDNA (COI gene) sequences of nematodes belonging to the genus Pratylenchus from GenBank. The consensus trees based on ITS and 28S rDNA showed that the P. hippeastri is represented by a monophyletic group. P. hippeastri is close to P. scribneri, which is not shown by the phylogenetic analysis. These two species, despite the differences mentioned by P. hippeastri vs four incisures reach the end of the female tail in P. scribneri) (see P. scribneri (EU669958) is not accessible, judging on the similarity among that and with the two P. hippeastri  is not logic. In addition, based on the phylogenetic analysis, P. hippeastri place close to P. floridensis and P. parafloridensis in one clade with 100 posterior probability values, as indicated by hippeastri’. The mentioned amphimictic species recovered from the same geographical region  differ in spermatheca  and tail end morphology   see . Except idensis) . The pai


Salvia officinalis L.) is a good source of antioxidant compounds, carnosic acid and carnosol being the prominent ones. Both are soluble in CO2, and our goal was to investigate the application of supercritical CO2 extraction to obtain sage extracts rich in these compounds. The effect of pressure, temperature, and CO2 flow rate on the carnosic acid and carnosol yield was studied. These variables were optimized by response surface methodology (RSM). The pressure significantly affected carnosol extraction, while the extraction of carnosic acid was affected by the pressure, temperature, and CO2 flow rate. Carnosic acid content varied from 0.29–120.0 µg mg−1, and carnosol content from 0.46–65.5 µg mg−1. The optimal conditions according to RSM were a pressure of 29.5 MPa, a temperature of 49.1 °C, and a CO2 flow rate of 3 kg h−1, and the sage extract yield was calculated to be 6.54%, carnosic acid content 105 µg mg−1, and carnosol content 56.3 µg mg−1. The antioxidant activities of the sage extracts were evaluated by the scavenging activities of 2,2-diphenyl-1-picrylhydrazyl (DPPH). Sage extract obtained at 30 MPa and 40 °C with 2 kg h−1 CO2 flow rate with a carnosic acid content of 72 µg mg−1 and carnosol content of 55 µg mg−1 exhibited the highest antioxidant activity (80.0 ± 0.68%) amongst the investigated supercritical fluid extracts at 25 µg mL−1 concentration. The antimicrobial properties of extracts were tested on four bacterial strains: Escherichia coli, Pseudomonas aeruginosa, Bacillus subtilis, and Staphylococcus aureus. The extract with a carnosic acid content of 116 µg mg−1 and a carnosol content of 60.6 µg mg−1 was found to be the most potent agent against B. subtilis.Sage ( Salvia officinalis L.), a member of the Lamiaceae family, is an aromatic medicinal plant often used in culinary preparations and in folk medicine for various health conditions, such as fever and sweating, rheumatism, bronchitis, and mental and nervous disorders [Sage  and flavonoids  ,8, whileCarnosic acid is a phenolic diterpene belonging to the class of the secondary plant metabolites called terpenoids, isoprenoids, or terpenes . Carnoso−1 DW and 1.34 mg g−1 DW carnosic acid and carnosol. Carnosic acid was proven to be very efficient in the prevention of fish oil oxidation and its antioxidant activity was shown to be stronger than that of vitamin E [Carnosic acid is mostly present in the aerial parts of the plant, and the content of carnosic acid and carnosol in sage leaves increases with senescence . Dried ritamin E , while Gitamin E  also fouitamin E ,23,24. Fitamin E  found thitamin E . These aSo far, various extraction techniques have been employed to obtain sage extracts rich in bioactive components, hydrodistillation ,29,30,31SFE has attracted attention in recent years in the process of separation as a highly desirable “green“ solvent, since it is a non-toxic, non-flammable, odorless, tasteless, inexpensive, readily available in large quantities, and environmentally friendly solvent . Since aIn our latest paper , we inveA literature search revealed that there is no data available on SFE parameter optimization in order to achieve the optimal content of carnosic acid and carnosol in sage extracts, as it is presented in our research. Both Babović et al.  and Glis2 flow rate) on: (1) the content of carnosic acid and carnosol in sage extracts analyzed by HPLC; (2) defining the optimal extraction conditions by RSM for the desired antioxidant components (carnosic acid and carnosol); and (3) defining the optimal extraction conditions for antioxidant and antibacterial activity.Considering all the above, the objectives of this study were focused on investigating the influence of various SFE parameters  pure . 2,2-Diphenyl-1-picrylhydrazyl (DPPH), ascorbic acid (AA), gallic acid, carnosic acid, and carnosol were purchased from the Sigma Chemical Co. . Other solvents were obtained from J.T. Baker .Commercial COS. officinalis L.) were obtained in spring 2016 from herbal pharmacy Vextra d.o.o. . In the sage leaves, moisture content (12.42% with an S.D. of 0.06) and the particle size of the ground leaves was determined as described previously [Sage leaves  was used for data analysis.An SFE system, explained in detail in , was useHPLC analysis of carnosol and carnosic acid was performed on a Varian ProStar system , with a Varian ProStar 230 Solvent Delivery Module, a ProStar 500 Column Valve Module, and a ProStar 330 Photodiode Array detector. Chromatographic separation was performed on a COSMOSIL 5C18-MA-II  250 mm-long column with an internal diameter of 4.6 mm.3PO4 (in millipore water) as phase B, with a 60:40 ratio of A:B. The flow rate was 1.0 mL min−1, the injection volume was 20 μL, the UV detection wavelength was 230 nm, and the analysis was performed at room temperature.Separation of analyzed compounds was performed by isocratic elution for 40 min, where acetonitrile was used as phase A and 0.1% H−1). The linearity of the calibration curve was confirmed by R2 = 0.9997 for carnosic acid and R2 = 0.9997 for carnosol. For carnosic acid, the limit of detection (LOD) was 0.082 mg L−1, the limit of quantification (LOQ) was 0.273 mg L−1, and the compound retention time was 20.3 min. For carnosol, the LOD was 0.103 mg L−1, the LOQ was 0.344 mg L−1, and the compound retention time was 13.4 min.Standard stock solutions for carnosic acid and carnosol were prepared in a solvent and calibration was obtained at eight concentrations  and mixed with 0.2 mM DPPH radical solution. Ascorbic acid (AA) was used as a reference compound. All measurements were done in triplicate. The absorbance was measured at 517 nm, and DPPH scavenging activity was determined using Equation (1):b is the absorbance of 0.1 mM DPPH radical solution at λ = 517 nm, As is the absorbance of 0.1 mM extraction solution at λ = 517 nm, and Am is the absorbance of 0.1 mM solution mixture of tested extracts and DPPH radical at 517 nm.Total antioxidant activities of SFE sage leaf extracts were determined using the DPPH radical scavenging assay described earlier . The plaBacillus subtilis and Staphylococcus aureus, and two gram-negative Escherichia coli and Pseudomonas aeruginosa, were investigated. The four bacteria were isolates from various clinical specimens obtained from the Microbiology Service of the Public Health Institute of Osijek-Baranja County, Croatia. B. subtilis and E. coli were selected as two popular laboratory model organisms representing gram-positive and gram-negative bacteria, respectively. S. aureus and P. aeruginosa were selected as human pathogens representing gram-positive and gram-negative bacteria, respectively. Working cultures were prepared from subcultures and grown overnight in Muller Hinton Broth (MHB)  under optimal conditions for each microorganism. The antibacterial agent gentamicin  was dissolved in distilled water.Two gram-positive 50) values were determined by a modified broth microdilution method [50 were defined as the lowest concentration of the extract which completely inhibited the growth of a particular microorganism, and the concentration which inhibited 50% of growth, respectively. Assays were performed with sterile TPP 96-well plates  in a final volume of 200 μL. A total of 100 μL of midlogarithmic-phase bacterial cultures (5 × 105 CFU mL−1) in Mueller Hinton Broth were added to 100 μL of serially diluted extracts (250 to 0.122 μg mL−1). Wells containing bacterial inoculum without extracts (growth control) and wells containing only broth and ethanol (background control) were included in each plate. Controls were set up with ethanol in amounts corresponding to the highest quantity present in the test solution where appropriate. The experiments were replicated three times on different occasions with triplicate samples analyzed per replicate, and the antibacterial standard gentamycin was co-assayed under the same conditions. The microplates were incubated at 37 °C for 24 h, and the bacterial cell growth was assessed by measuring the optical density of cultures at 600 nm at zero (OD1) and 24 h (OD2) with a Tecan Spark Multimode Microplate Reader . The MIC was defined as the lowest concentrations of compound at which there was no visual turbidity due to microbial growth. Growth inhibition was estimated by the following formula:control is growth control at 24 h and ODcorr is OD2 − OD1.MIC and 50% growth reduction . All tests were performed at a level of significance of α = 0.05.2 flow rates of between 1–3 kg h−1 for 90 min, and the particle size of the plant material was 0.478 ± 0.36 mm. The same conditions were applied in this research as well, however we focused on the content of carnosic acid and carnosol in the obtained extracts, as prominent antioxidants in sage.Process parameters for SFE were determined by BBD and are tabulated in −1 of extract, depending on the applied extraction parameters. The lowest yield of carnosic acid was obtained at a pressure of 10 MPa and temperature of 50 °C, while the highest yield was obtained at 20 MPa and 40 °C  in the obtained extracts. The content of carnosic acid increased with the pressure and CO2 flow rate, while the increase of temperature decreased the content of carnosic acid. Interactions between extraction parameters (p > 0.05) did not show a significant influence on the extract carnosic acid composition.As is evident from p = 0.0014), i.e., the content of carnosol increased with the increase in pressure. Unlike the effect on carnosic acid, neither temperature (p = 0.1360), CO2 flow rate (p = 0.1258), nor interaction between parameters showed significant statistical influence on the content of carnosol.S. officinalis, the amounts of carnosic acid and carnosol were quantified as 14.6 mg g−1 DW and 0.4 mg g−1 DW, respectively [−1 and 12.40 ± 0.43 mg g−1, respectively [S. officinalis L. from Northern Italy, the content of carnosic acid was 0.2–7.1 g kg−1 of extract, while the content of carnosol was 1.1–9.0 g kg−1 of extract. In methanolic extracts of sage from Tunisia, the content of carnosic acid was 746–3110 µg g−1 of dry plant material weight, and depended on geographical location [According to previous research, the amounts of antioxidant components in plant extracts are determined by the type of extraction and solvent used . It is wectively . The conectively , respectectively . In methlocation . Additiolocation ,55,56. 2. The solubility of carnosic acid in SFE with ethanol as a co-solvent was investigated by Cháfer et al. [As already stated, the data describing the optimal conditions for the extraction of carnosic acid and carnosol from sage using SFE are not available in the literature. However, Caldera et al.  investigr et al. . The solS. officinalis extracts are given in R2 was 0.861 and 0.901 for carnosic acid and carnosol, respectively, which indicates that the empirical model shows a good fit with empirical data (R2 are close to 1). According to the ANOVA results (p ≤ 0.05), and the error analysis that showed a non-significant lack of fit (p = 0.0874–0.8893). Therefore, the influence of the SFE parameters we applied on carnosol and carnosic acid content can be described by a second-order polynomial model. Therefore, the optimization of the extraction process is necessary, and it can be achieved using BBD or some other design. Based on the BBD, the estimated coefficients of second-order response models for carnosol and carnosic acid in  results , the mod2 flow rate of 3 kg h−1. Under these optimal conditions, the yield of sage extract was calculated to be 6.54%, the carnosic acid content to be 105 µg mg−1, and the carnosol content to be 56.3 µg mg−1, which is in very close agreement with obtained experimental data  was recorded in sage extract obtained at 30 MPa and 40 °C with 2 kg h−1 CO2 flow rate with a carnosic acid content of 71.94 µg mg−1 and a carnosol content of 54.75 µg mg−1, whereas the lowest content (1.02 ± 0.02 mg of GAE g−1 of DM) was found in the case of sage extract obtained at 30 MPa and 60 °C with 2 kg h−1 CO2 flow rate with a carnosic acid content of 18.9 µg mg−1 and a carnosol content of 64.2 µg mg−1. The antioxidant activities of the supercritical fluid sage leaf extracts at a concentration of 25 µg mL−1 were evaluated by the scavenging activities of DPPH, as shown in −1 CO2 flow rate with a carnosic acid content of 71.9 µg mg−1 and a carnosol content of 54.8 µg mg−1 also exhibited the highest antioxidant activity (80.0 ± 0.68%) amongst the investigated supercritical extracts, whereas the lowest antioxidant activity (26.9 ± 0.91%) was found in the case of sage extract obtained at 30 MPa and 60 °C with 2 kg h−1 CO2 flow rate with a carnosic acid content of 18.9 µg mg−1 and a carnosol content of 64.2 µg mg−1. Non-parametric Spearman correlation analysis of all data points demonstrated significant (p < 0.050) strong positive correlation between the carnosic acid content and TPC results (R = 0.7909), and significant (p < 0.050) moderate positive correlation between the carnosic acid content and radical scavenging activity (R = 0.5636).The quantitative evaluation of total phenolics in supercritical fluid sage leaf extracts as estimated by the method of Folin–Ciocalteu revealed that −1 of DM . The higE. coli, P. aeruginosa, B. subtilis, and S. aureus. MIC and IC50 results are shown in Supercritical fluid extracts from sage leaves were tested for in vitro antibacterial activity against E. coli, P. aeruginosa, B. subtilis, and S. aureus. Extracts were more active against gram-positive bacteria than gram-negative bacteria. The main reason for the differences in bacterial susceptibility could be the outer membrane surrounding the cell wall in gram-negative bacteria, which restricts the diffusion of compounds through its lipopolysaccharide covering, as previously reported [B. subtilis and the lowest activity against E. coli. As reported, carnosic acid, carnosol, rosmanol, and ferruginol are also responsible for the biological activity of sage  along with the phenolic rosmarinic and salvianolic acids [50 however are not as accurate. Among them, as shown in −1 and a carnosol content of 60.6 µg mg−1 showed the lowest IC50 10.82 ± 0.02 µg mL−1 against B. subtilis, and the extract with a carnosic acid content of 66.2 µg mg−1 and a carnosol content of 61.02 µg mg−1 showed the highest IC50 40.4 ± 0.19 µg mL−1 against E. coli. As shown in −1 extract concentration, while at the extract concentration of 15.6 µg mL−1 growth inhibition varied from 14.5–76.8%. Among them, the extract with a carnosic acid content of 116 µg mg−1 and a carnosol content of 60.6 µg mg−1  (9.15 ± 0.09 mg of GAE g−1 of DM) and highest antioxidant activity (79.98 ± 0.68%) at 25 µg mL−1 concentration amongst the investigated supercritical fluid sage extracts was recorded in extract obtained at 30 MPa and 40 °C with 2 kg h−1 CO2 flow rate with a carnosic acid content of 71.94 µg mg−1 and a carnosol content of 54.75 µg mg−1. In this study, the best antibacterial efficiency was confirmed for supercritical fluid sage extract formulations with higher carnosic acid content against all the tested strains, especially gram-positive B. subtilis. Gram-negative tested strains were less susceptible, which could be related to the lower permeability of their surface for phenolic compounds.In this work, optimization of the extraction of carnosol and carnosic acid from sage leaves using SFE was performed. Only the pressure significantly affected the extraction of carnosol, while in the case of carnosic acid, all investigated parameters—pressure, temperature, and CO


The aim of the study was to compare visual acuity, refractive results, safety, and efficacy of TPRK with AAPRK as primary outcomes and surgical time, pain scores, haze levels, and healing time as secondary outcomes in TPRK and AAPRK groups.  Security Forces Hospital, Ophthalmology Department, Riyadh, Kingdom of Saudi Arabia.  Prospective, nonrandomized case-control comparative study.  A total of 200 eyes of 100 consecutive patients were included. One hundred eyes underwent TPRK in the right eye (study group), and 100 eyes underwent AAPRK in the left eye (control group). Ablations were performed with the Schwind Amaris excimer LASER750S. Clinical outcomes during 6 months' follow-up were compared.  The mean age of patients was 28.3 ± 6.3, 77 were females and 23 males. The mean surgical time was 162.17 ±  14.827 s and 243.24  ±  98.69 s, respectively. At day 1, the UDVA mean was 0.7 in 87% of eyes in the TPRK group while it was 0.5 in 45% of eyes in AAPRK; at week 1, it was 0.9 in 88% of eyes in the TPRK group and 0.6 in 60% of eyes in AAPRK. The mean pain scores were less and lower incidence of corneal haze in the TPRK. Complete epithelial healing time was shorter in TPRK, 3.20 ± 0.686 and 4.60 ± 1.969 days, respectively. NCT03569423. TPRK and AAPRK produce similar results 6 months postoperatively. However, in the early postoperative period, there were significant differences in UDVA, pain score, level of haze, and complete epithelial healing time. The pain scores were lower, level of haze was less, and healing time was shorter in the TPRK group which provided patient better felling and comfort in this period. Both of procedures are effective and safe for correction of myopia and compound myopic astigmatism. This trial is registered with  Photoe center . A numbee center –16. ThusD, a stable refraction for at least 1 year before the surgery, contact lens discontinuation for at least 3 weeks, and an estimated stromal corneal bed thickness of >330 μm at the thinnest location. Exclusion criteria were previous ocular surgery, active ocular diseases, corneal dystrophy, retinal disease, glaucoma, dry eye, a history of severe eye trauma, irregular astigmatism or suspected keratoconus on corneal topography, and systemic disease that could affect corneal wound healing such as collagen diseases, diabetes mellitus, and pregnancy.Our study is a prospective, consecutive, and nonrandomized cohort study that includes eyes that underwent either single-step TPRK or AAPRK between February 2017 and April 2018, at the Security Forces Hospital, Ophthalmology Department, Riyadh, Kingdom of Saudi Arabia. The study was approved by the local ethical board committee. Before the surgical procedure, each patient was adequately informed about the study as well as the risks and benefits of the surgery and signed informed consent in accordance with the Declaration of Helsinki. The inclusion criteria were as follows: age over 18 years, primary myopia or compound myopic astigmatism, preoperative manifest refraction spherical equivalent (MRSE) within the range of −1.50 to −7 A total of 200 eyes of 100 consecutive patients were included; one hundred eyes underwent TPRK (study group) and 100 eyes underwent AAPRK (control group). The study design choice of the procedure was fixed for each patient: the right eye underwent TPRK and the contralateral left eye AAPRK. Patient's demographics and preoperative variables are demonstrated in The preoperative examination included UDVA, BCDVA, manifest and cycloplegic refraction, slit lamp biomicroscopy, tonometry, Pentacam camera , tomography , and dilated fundus examination using binocular ophthalmoscopy. Contact lenses use and medical history, including any systemic diseases, were recorded.D 45%, water 55%) for 7 days. The postoperative regimen included tobradex eye drops 0.3%  with tapering dose for 1 month starting with QID/1 week, TID/1 week, BID/1 week and once a day/1 week, moxifloxacin drops 0.5%  for 2 weeks, and sodium hyaluronate 0.2%  drop/2 hours and a gradual decreasing of the frequency for 3 months. A pain killer oral medication tablet/6 hours was used in the first postoperative days if needed.All surgeries were performed with 6th-generation Amaris excimer LASER 193 nm, version 750 S . Ablations were based on aberration-free algorithms calculated using ORK-CAM software with the beam size of 0.54 mm full width and high-speed eye tracking. Treatments were performed by 2 surgeons (BA and ESH) using an identical surgical protocol. The treatments were mostly aimed at emmetropia. Before the surgery, tetracaine hydrochloride 0.5% ophthalmic solution  and moxifloxacin 0.5%  drops were instilled 3 times within a 5-minute interval. The eyelids were prepared with antiseptic chlorhexidine gluconate 0.05% solution  and opened using a wire lid speculum. In the AAPRK group, the cornea was exposed to a 20% ethyl alcohol solution for 25 seconds with the use of a well. Subsequently, a superficial cut of the epithelium was made with either an 8.5 or 9.5 mm diameter trephine. The epithelium was mechanically debrided with the well or with a blunt spatula, and then, LASER treatment with the same machine was initiated. In the TPRK group, where aspheric aberration-free TPRK ablation algorithm was used (Schwind eye-tech-solutions), the epithelium was removed during laser ablation only from the area of the total ablation zone. In both groups and in all cases, immediately after treatment, the eye was washed with balanced salt solution (BSS) for 20 seconds. Then, to fight against postoperative corneal haze, mitomycin C (MMC) 0.02% was applied for 30 seconds followed by copious irrigation of the eye with BSS. Intraoperative complications were not noted, and surgical time starting from eyelid speculum insertion to the time of its removal at the end of the procedure was recorded. After the surgery, a bandage contact lens was applied , and the refractive astigmatism is less than −1.50 D in both groups. The mean keratometry reading was 44.50 ± 1.45 and 43.60 ± 1.70 d (P=0.33), the mean preoperative central corneal thickness (CCT) was 490 ± 4.80 and 496 ± 4.60 μm (P=0.308), the minimal estimated stromal residual thickness was 340 ± 18 in the TPRK group and 345 ± 17 μm (P=0.33) in the AAPRK group, the mean ablation time was 29.71  ±  7.62 s in the TPRK group and 12.33  ±  6.138 s in the AAPRK group (P < 0.001), whereas the mean surgical time of the whole procedure was 162.17 ± 14.827 s and 243.24  ±  98.69 s, respectively (P < 0.001). In the TPRK and AAPRK groups, respectively, the mean diameter of the optical zone was 6.734  ±  0.194 and 6.745  ±  0.201 mm (P=0.988) and the transition zone was 1.036 ± 0.371 and 0.995 ± 0.364 mm (P=0.645). There were no statistically significant differences between the two groups regarding the mean 1, 3, and 6 months postoperative MRSE, as shown in D in the TPRK group and −0.165 ±  0.476 D in the AAPRK group (P=0.986). The mean postoperative MRSE at 3 months was −0.110 ± 0.418 D in the TPRK group and −0.113 ± 0.418 in the AAPRK group (P=1). The mean postoperative MRSE at 6 months was −0.0500 ± 0.337 D in the TPRK group and −0.0450 ± 0.338 D in the AAPRK group (P=1).The mean age of the patients was 28.3 ± 6.3 years (range 18–50 years); 77 were females and 23 were males. D, 20% within +0.25 to ± 0.5 D, 17% within −0.50 to −0.75 D, and no eyes (0%) within −0.75 to −1.0 D; the respective values in the AAPRK group were 63%, 21%, 15%, and 1%. The differences were not statistically significant. Regarding the preoperative mean UDVA and BCDVA, there are no statistically significant differences between groups in which it was for UDVA 0.229 ± 0.158 in the TPRK group and 0.272 ± 0.185 in the AAPRK group (P=0.981) and for BCDVA 1.001 ± 0.0577 in the TPRK group and 1.006 ± 0.0052 in the AAPRK group (P=0.15). P < 0.001), with visual stability (< ± 0.50 D difference in two consecutive visits) as well as no significant differences at 3 and 6 months (P=0.081 & 0.613); the values were 0.713 ± 0.074 , 0.901 ± 0.050 , 1.018 ± 0.110 , 1.033 ± 0.094 , and 1.044 ± 0.083 , respectively, in the TPRK group while the values were 0.479 ± 0.083 , 0.56 ± 0.049 , 0.926 ± 0.061 , 0.990 ± 0.038 , and 1.024 ± 0.065 , respectively, in the AAPRK group. P < 0.001), where at day 1, it was 0.7 in 87% of eyes in the TPRK group and 0.5 in 45% of eyes in AAPRK and at week 1, it was 0.9 in 88% of eyes in the TPRK group and 0.6 in 60% of eyes in AAPRK. The postoperative mean UDVA values were 0.9 in 95%, 1 in 90%, and ≥1 in 100% at 1, 3, and 6 months, respectively, in the TPRK group while the corresponding values were 0.9 in 90%, 1 in 88%, and ≥1 in 100% in the AAPRK group. There are no statistically significant differences in postoperative BCDVA mean in both of groups at 1, 3, and 6 months, where the values were 1.027 ± 0.101, 1.036 ± 0.091, and 1.044 ± 0.083 in the TPRK group, respectively, and the corresponding values were 0.936 ± 0.057, 0.993 ± 0.035, and 1.024 ± 0.065 in the AAPRK group, respectively. Regarding the efficacy of the procedures, we compared the ratio of the mean postoperative UDVA to the mean preoperative BCDVA (efficacy index) for both groups, as shown in P < 0.001), but no difference on the other tested time points was detected. For the safety of the procedure, we compared the ratio of the mean postoperative BCDVA to the mean preoperative BCDVA (safety index) for both groups, as shown in P values were <0.001. A lower incidence of postoperative corneal haze was detected with the slit lamp for the TPRK group compared to the AAPRK group at all tested time points: 1 week, 1 month, and 3 months, as shown in P values were 0.019, 0.008, and 0.033, respectively. During the follow-up, the corneal haze intensity had a tendency to decrease until reaching to postoperative 6 months, where there was no haze in both the groups. Regarding complete corneal epithelial healing time, the mean was shorter in the TPRK group than in AAPRK, in which it was 3.20 ± 0.686 and 4.60 ± 1.969 days, respectively (P < 0.001), and as shown in P < 0.001).At 3 months, the postoperative mean MRSE was in 63% of eyes within ± 0.25 P=0.46). The ratio for moderate satisfaction was 10% for TPRK and 12% for AAPRK, respectively (P=0.45), and none of patients recorded with low or no satisfaction. All patients would consider having the surgery again. There was no statistically significant difference in the incidence of other postoperative complications, which included more intensive dry eye symptoms in 3% of eyes after TPRK and 4% after AAPRK and decreased visual acuity at night tested by covering one eye alternatively, and it was 2% of eyes after TPRK and 3% after AAPRK. No postoperative complications, such as keratitis, delayed reepithelialization, or recurrent corneal erosion, were reported to a level of clinical significance in our study.At the end of the study, in the TPRK group, 90% of patients declared high satisfaction with the surgery compared to 88% of patients in AAPRK (P < 0.001) as well as similar results were obtained by Fadlallah et al. [P=0.02), and also in agreement with Celik et al.'s [P=0.01).TPRK was known as a complementary procedure after LASIK, keratoplasty, and radial keratotomy –20. In 1h et al. , in whicet al.'s  results,et al.'s , in whicet al.'s , in whicet al.'s , but in et al.'s , in whicet al.'s , in whicet al.'s , in whicA potential disadvantage of TPRK is the higher total excimer LASER energy load. In our study, mean ablation time was 140% longer in the TPRK group; however, the Schwind LASER machine tuned so that the majority of the laser energy was delivered to the epithelium, and it was decreased gradually in stromal treatment reaching to its lowest level.TPRK and AAPRK produce similar outcome results 3 months postoperatively and after 6 months follow-up. There is shorter surgical time in the TPRK technique than in AAPRK. However, in early postoperative period, there were significant differences in UDVA, pain score, level of haze, and complete corneal epithelial healing time, in which the pain scores were lower, level of haze was less, and healing time was shorter in the TPRK group which resulted in the patient felling that it is a friendly procedure and higher patient comfort in this early postoperative period. Both of procedures are predictable, effective, and safe for correction of myopia and compound myopic astigmatism.


The device showed specific capacitance value of 150 F/g at 1 A/g current density, with a capacitance retention value of 93.33% at higher current density (10 A/g), indicating a high rate capability. An energy density of 15.30 Whkg−1 with a power density of 1716 Wkg−1 was obtained at the current density of 1 A/g. The values of areal capacitance, power density, and energy density, achieved at the current density of 5 mAcm−2, were 97.38 mFcm−2, 9.93 mWhcm−2, and 1.1 Wcm−2, respectively. Additionally, the device showed very low solution and charge transfer resistance . A device was also fabricated utilizing copper as current collector; however, a lower value of specific capacitance (82 F/g) was observed in this case.An eco-friendly solid-state symmetric ultracapacitor (Uc) device was fabricated using a polyaniline graphene oxide composite co-doped with sulfuric acid (H To utilized, interrupted/or intermittent power outputs from natural renewable energy resources, it is necessary to evolve efficient energy storage systems . BatteriSolid-state Ucs are composed of electrodes, solid electrolyte, and separator to a solid whole. These Ucs are preferred over their liquid counterparts due to their light-weight, high-safety, high-flexibility, and eco-friendly nature ,4. SolidElectrode materials for Ucs are generally divided into two categories ,6. One iMostly gel electrolytes are used in solid state Ucs . However2SO4 gel, which is known for its high conductivity and flexibility, was employed as polymer electrolyte  It It−1 was−2 was achieved at 5 mAcm−2, with a power density of 9.93 mWhcm−2 and energy density of 1.1 Wcm−2  a. A maxi.1 Wcm−2 b. These n), n1 (0.902), CPE2 (0.036 S.sn), n2 (0.800), and W (1 × 10−6 S.s1/2). There was a very small value of W because of the smallest diffusion resistance of the composites [To compliment the results from the CV and GCD analysis, EIS was carried out. mposites . The valmposites .0 value at phase angle −45° is 1.42 s. The smaller value of t0 means a higher knee frequency and a higher rate capability [The Bode plot c has a ppability .Due to the many advantages of solid-state Ucs, copper sheets were also used as current collectors to fabricate solid-state symmetric device, as it is much cheaper than gold. Cyclic voltammetry analysis was accomplished in the potential range of 0 to 0.6 V at various scan rates of 10, 30, 50, 70, 100, 200, 300, 400, and 500 mV/s a,b. ThesThe GCD analysis of the device, fabricated with copper as current collector, was executed in the potential range of 0 to 0.6 V at several current densities. As can be seen from 2SO4 gel as electrolyte, and two different PANI–GO composites as electrode materials. There was difference in the overall performance of the device when copper was used as current collector instead of gold, indicating that the current collectors do contribute to the performance of the device. The use of PAV–H2SO4 gel electrolyte makes the device eco-friendlier by minimizing the risk of electrolyte leakage. While the difference in dopants also showed a pronounced effect on the properties of the composite generally and its overall performance as electrode material in the device specifically. Contributions from pseudo capacitance of PANI and EDL capacitance of GO were visible in the composite material while DBSA or CSA as dopants in combination with H2SO4 also affected the results. Apparently all the combined effects contributed to the enhanced capacitance, energy density, and power density of the fabricated device. Best performance was achieved the for ds@PANI/GO composite where DBSA and H2SO4 were used as dopants. Highest specific capacitance value of 150 F/g was achieved at 1 A/g current density. The device showed excellent rate capability with capacitance retention of 93.33% at higher current density (10 A/g). At 1 A/g, maximum energy density of 15.30 Whkg−1 with a power density of 1716 Wkg−1 was obtained. Its maximum areal capacitance was 97.38 mFcm−2 at 5 mAcm−2. The device fabricated with copper as current collector, also manifested capacitive response and showed 82 F/g specific capacitance value at 2 A/g current density. However, its performance was lower than the device fabricated with gold as current collector.Solid-state symmetric Uc devices were fabricated by utilizing gold or copper as current collectors, PAV-H


To fabricate porous structures at the nanometer scale, Co-based metal-organic frameworks (MOFs), namely a cobalt Prussian blue analogue 6]2), was used as a porous template for the CoS2. Then, controlled sulfurization annealing converted the Co-PBA to mono-phase CoS2 nanoparticles with ~ 4 nm pores, resulting in a large surface area of 915.6 m2 g−1. The electrocatalysts had high activity for overall water splitting, and the overpotentials of the oxygen evolution reaction and hydrogen evolution reaction under the operating conditions were 298 mV and −196 mV, respectively, at 10 mA cm−2.Both high activity and mass production potential are important for bifunctional electrocatalysts for overall water splitting. Catalytic activity enhancement was demonstrated through the formation of CoS Although there are a variety of technologies to produce hydrogen energy, electrochemical water splitting is one of the most promising choices due to commercial aspects10.To replace depleting fossil fuels, the development of environmentally-friendly and sustainable energy sources has been strongly urged. Among alternative energy sources, hydrogen-based energy sources are one of the most promising candidates due to their outstanding energy density, high energy conversion efficiency, and environmental friendliness12. Transition metal oxides14, hydroxides16, carbide17, nitride18, phosphide19, and sulfides22 have been studied as OER electrocatalysts under alkaline conditions, and transition metal sulfides22, phosphides7, carbonitride23, and selenides24 have been studied as HER electrocatalysts under acidic conditions. In regard to OER and HER performance, the effects of activation and optimization of electrocatalysts have recently been reported23. Furthermore, with a growing demand for simplicity and cost effectiveness, the need for bifunctional electrocatalysts, which operate in the same electrolyzer, is rapidly increasing26.Electrochemical water splitting consists of two half reactions, namely the oxygen evolution reaction (OER) and the hydrogen evolution reaction (HER). Although noble metal electrocatalysts, such as Pt (for HER) and Ru- or Ir-based materials (for OER), show excellent catalytic performance, they are difficult to apply on a large scale because of cost issues. Thus, active electrocatalysts based on earth-abundant elements, such as transition metal compounds, have been extensively studied to replace noble metals228, NiS229, and CoS226, have been proposed as candidates for bifunctional electrocatalysts30. Among them, cobalt disulfide (CoS2) has been reported to exhibit high electrical conductivity31 and excellent activity for both the OER and the HER32. Since water splitting involves hydrogen and oxygen gas evolution reactions, porosity in the electrocatalysts is very important for improving their performance by facilitating gas emission and exposing active sites26. Therefore, to further increase the catalytic activity of CoS2, it is necessary to synthesize porous CoS2 with nanometer scale pores.Cubic pyrite-phase transition metal dichalcogenides, such as FeS35. However, MOFs have a low electrical conductivity and are not suitable as electrocatalysts, which require a large current density for electrical efficiency.Metal-organic frameworks (MOFs), which comprise metal ions and organic linkers, can provide a large surface area with open structures, so they are used in many electrochemical applications, such as batteries, capacitors, and catalysts2 with ~ 4 nanometer-scale pores as bifunctional water splitting electrical catalysts. Cobalt-based MOFs, namely a cobalt Prussian blue analogue 6]2), were used as a starting material. The Co-PBA was then sulfurized in thermodynamically controlled conditions to remove the organic linkers in the MOFs, resulting in pure and mono-phase CoS2. The synthetic process was predicted based on thermodynamics because cobalt sulfide has been reported in various phases36, where the phase depends on the S/Co ratio, such as CoS37, Co9S838, and CoS240. Thermodynamic calculations control the sulfur vapor pressure depending on the amount of cobalt-based starting materials before sulfurization. Such MOF-driven CoS2 nanoparticles still preserve the nonporous structure in the starting MOFs, so high electrocatalytic activities are achieved.Here, we fabricated mono-phase CoS41.Figure 2 is schematically shown in Fig. For thermodynamically controlled sulfurization of Co-PBAs, components of the material and process parameters should be determined before the experiment. The synthesis of MOF-driven CoS9S8 was produced at first, and then the amount of CoS2 increased. For a sulfur content with a ratio of more than 0.5 (15 mg), a CoS2 single phase can be obtained. However, when the sulfur content exceeded 0.9 (27 mg), the liquid sulfur phase remained.The Co-S-O ternary phase diagram at 500 °C was used to find the mole fraction of cobalt and oxygen for the sulfurization of the cobalt-based MOFs, and the determined value was set as the sulfur amount  of sulfur synthesized the Co single phase and a 0.1 ratio (3 mg) of sulfur synthesized the Co9S8 phase. As a result of the XRD analysis, it was determined that annealing Co-PBAs without sulfur corresponds to the Co reference card in Fig. 9S8 reference card in Fig. 2 is the mono-phase.Figure 2 nanoparticles. The SEM  planes. The same result was obtained from the FFT pattern in the inset of Fig. 2 was highly crystalline with an (002) preferred orientation. The energy dispersive X-ray spectroscopy (EDX) was shown that the Co and S of synthesized MOF-driven CoS2 were uniformly distributed , and commercial CoS2 were displayed in Fig. 23 edge to higher energy was observed depending on higher S/Co ratio of cobalt sulfide42.Figure SEM Fig.  and TEM SEM Fig.  after suted Fig. . Microst2, shown in Fig. 2, the BET specific surface area in Fig. 2 g−1, compared with 6.1, 46.0, and 60.1 m2 g−1 for commercial CoS2, MOF-driven Co, and Co9S8, respectively  desorption was measured to quantitatively express the pore diameter shown in Fig. 2 (red line) and at ~20 nm . A gradually increasing peak includes the surface of particles because there is no selectivity (pore and surface) for the adsorption/desorption of N2 during BET measurements. Although relatively low intensity, the peak of MOF-driven Co, Co9S8 were also detected at about 3.5 nm. Increasing the sulfur ratio leads to increasing the sulfur base gas  were shown in Fig. 2 on Ni foam electrode and MOF-driven CoS2 on Ni foam electrode are 0.7 and 1.5 mF cm−2 respectively, confirmed that the ECSA difference was about 2.1-fold . The ECSA of each electrode was calculated in Fig. The porous structures were also observed in the TEM images, which confirmed the BET analysis. In Fig. 2 as shown in Fig. 1/2 and Co 2p3/2 respectively. Each peak can split into three sub-peaks, which are located at 796.7, 795.1 and 793.7 eV for the Co 2p1/2 spectrum and 781, 779.7 and 778.5 eV for the Co 2p3/2 spectrum. As indicated in Fig. 2+ and Co3+ 49. The S 2p spectrum shown in Fig. 1/2 (163.6 eV) and 2p3/2 (162.5 eV). The peak at 168 eV is typically indexed as a sulfur oxide50. In this result, the sulfur oxide peak has a negligibly low intensity compared with other previous reports that describe hydrothermally synthesized CoS2. The results of the physical and chemical property analysis through XRD and XPS show that the synthesized CoS2 had high purity.XPS was conducted to observe the chemical and electronic states of MOF-driven CoS2 nanoparticles on the Ni foam electrode, linear sweep voltammetry (LSV) was conducted for the bare Ni foam, Ir foil, Pt electrode, commercial CoS2, and MOF-driven CoS2. The OER and HER were performed with a conventional three-electrode system in 1.0 M KOH (see for methods section for details). Polarization measurements were conducted in the potential range between 1.2 and 1.7 V (vs. reversible hydrogen electrode (RHE)) for the OER at a scan rate of 1 mV s−1 and between −0.4 and 0.0 V (vs. RHE) for the HER at a scan rate of 5 mV s−1. First, the OER activity of the electrocatalysts was measured as the overpotential at a current density of 10 mA cm−2 and the Tafel slope. Figure 2 electrode shows a low overpotential requirement of 298 mV at 10 mA cm−2, while the others show a higher overpotential. Under the same conditions, the overpotentials of the MOF-driven Co, MOF-driven Co9S8, commercial CoS2, IrO2, and MOF-driven Co3O4 were 411, 362, 379, 374, and 359 mV, respectively. The LSVs of Ir foil, Pt electrode, and Ni foam were conducted  to Co(IV) transition2 electrode, which had the lowest overpotential in the polarization curves, showed a low Tafel slope value (94 mV dec−1).The Tafel plot was plotted based on the polarization curves, and the Tafel slope was calculated Fig. . As with2, 0, 0.1, and 0.5 ratios of sulfur/Co-PBAs  was conducted at 300 mV (vs. RHE). Equivalent circuit model was shown in inset of Fig. 2 was shown the lowest charge transfer resistance.In Fig. 2 nanoparticles, a long-term durability test was conducted using the chronoamperometric method 51.As shown in Fig. 2 Fig.  and CoOO2 Fig.  were obsted Fig. . Althougted Fig. . The pea2 was observed  was increased, which this phenomenon was also reported in other work6.After carrying out the HER durability test, TEM analysis was also conducted Fig. . Similarved Fig. . EDX mapved Fig. . In EDX 2 on Ni foam. The potential range was from 0.0 to 2.0 V. As shown in Fig. −2. The durability test was also conducted for symmetric full-cells 6]2 powder, was used as a starting material before sulfurization. The Co-PBA was synthesized through a facile precipitation method. Two types of solutions were used for precipitation. The recipe for the type 1 solution was 30 mM cobalt acetate (Co(CH3COO)2∙4H2O, Aldrich) and 17 mM sodium citrate  in deionized water (DIW). The concentration of potassium hexacyanocobaltate (III) (K3[Co(CN)6], Sigma-Aldrich) was 20 mM in DIW41. Then, the type 1 solution was dropwise added into the type 2 solution through a syringe pump at 400 ml/hr and vigorously stirred for 10 min. Subsequently, the mixed solution was aged for 18 hours at room temperature. The dispersed precipitate was filtered through a vacuum pump and washed with DIW several times to remove residues. Finally, the obtained powder was dried in an oven at 60 °C for 12 hours.First, the cobalt Prussian blue analogue (Co-PBA), namely Co2) nanoparticles were synthesized through thermal treatment. The 30 mg of the synthesized Co-PBA and certain amounts of sulfur  were loaded in a 5 ml ampoule. After that, the prepared ampoule was sealed through a vacuum pump under 0.1 Torr. Finally, the sealed ampoule was thermally treated in a furnace at 500 °C for 2 hours at a ramp rate of 5 °C/min7.Second, the cobalt disulfide (CoS2 nanoparticles were dispersed in a mixture of DIW (800 μl), ethanol , and Nafion  and sonicated for 30 min. After dispersion, 50 μl of the mixed ink was coated on the Ni foam (Aldrich) by drop casting through a micropipette. Finally, the coated electrode was dried in an oven at 60 °C for 12 hours. The ink preparation for the Co, Co9S8, Co3O4, commercial CoS2 powder (Aldrich), and IrO2 powder (Aldrich) was similar.To estimate the electrochemical performance, an ink was prepared. The 4 mg of synthesized CoS58.The ternary phase diagram, and analysis graphs of expected products depending on sulfur amount were drawn with a thermochemical database program (FACTSAGE software). The database used in this study was the FACT pure substances database (FactPS)2 nanoparticles, including the Co-PBA, and acquisition of the FFT patterns was conducted using TEM . Additionally, the microstructure, including the size and morphologies of the synthesized nanoparticles, was observed using FE-SEM . The surface area was conducted using a BET analyzer with N2 adsorption/desorption at 77.3 K .Phase analysis of the synthesized nanoparticles was performed using XRD . Microstructural analysis of the synthesized CoS-1 for the OER and between −0.4 and 0.0 V (vs. RHE) for the HER. In the case of overall water splitting, both electrodes were prepared using a potential range between 0.0 and 2.0 V. In HER and overall water splitting LSVs, the scan rate was fixed at 5 mV s−1. Electrochemical surface area (ECSA) was conducted using cyclic voltammetry (CV). CV was conducted in the voltage range between 0.18 and 0.28 V (vs. RHE) at a scan rate of 5, 10, 25, 50, 100, 200, 400, 600, 800, and 1000 mV s−1. The linear slope was calculated by plotting ΔJ at 0.23 V (vs. RHE) depending on scan rates59. EIS was performed within a frequency range from 100,000 Hz to 0.01 Hz at 300 mV (vs. RHE)60.LSV of each electrode was performed in a three-electrode system using a potentiostat . The working electrode was the prepared catalyst electrode. The counter and reference electrodes were Pt foil and a saturated calomel electrode (SCE) , respectively, in 1.0 M KOH (Sigma-Aldrich). The LSV was conducted in the potential range between 1.2 and 1.7 V (vs. RHE) with a scan rate of 1 mV sSupplementary Information


Agricultural wastes such as rice husks (RHs) are valuable due to their feasibility to be converted into carbon materials, low cost, and abundancy in contrast to the conventional carbon material sources. In this study, RHs are carbonized at various temperatures from low to high temperatures, and their electromagnetic (EM) wave absorption properties are evaluated. Carbon materials, silicon carbide (SiC) whiskers, and SiC particles are obtained from RHs carbonized at 1500 °C (CRH1500) for 0.5 h with presence of Ar gas at 1 atm. In order to evaluate their EM wave absorption performance, complex permittivity and permeability are measured by using vector network analyzer, and the values are utilized in the reflection loss (R.L.) calculation according to the transmission line theory. CRH1500, 40 wt% with thickness of 1.6 mm exhibits minimum R.L. of ≈−55.4 dB (>99.9997% absorption) at 11.37 GHz and response bandwidth  of 4.21 GHz. Low‐cost and abundant RHs, carbonized at various temperatures, show significant absorption performance. Their absorption performance and response bandwidth are highly dependent on matching thickness, indicating that they can be easily modulated for promising electromagnetic wave absorber materials. The disclosure of unnecessary or excessive electromagnetic (EM) wave emission are expected due to the extensive utilization of devices/applications associated with EM wave especially at GHz frequency ranges  in electronic fields, wireless communication, and radar.Recently, alternative functional absorber materials derived from biomass materials or agro‐based waste materials such as rice husk,RHs are lignocellulosic materials, which is beneficial to convert them into raw carbon materials together with silicon content through carbonization process using heat treatment.The dried RH samples went through carbonization at various temperatures of 800, 1500, and 2200 °C. Typically, the carbonization of raw RHs was at 800 °C, 1 h by utilizing furnace, in argon gas atmosphere. Next, the RHs carbonized at 800 °C were once more loaded into graphite box; further heat treated at 1500 °C, 0.5 h by utilizing graphite resistance furnace operating with the supply of argon gas at 1 atm. Similar process was repeated for the carbonization of RHs at 2200 °C. Finally, the carbonized RHs were crushed into powder within few micrometer range, and they will be denoted as CRH, 800 °C carbonized RHs will be denoted as CRH800, 1500 °C carbonized RHs will be denoted as CRH1500, and 2200 °C carbonized RHs will be denoted as CRH2200, hereafter.Their structures and morphologies were observed using field emission scanning electron microscope  and transmission electron microscope  with an accelerating voltage of 15 and 200 kV, respectively. Energy dispersive X‐ray spectroscopy (EDS) equipped together with TEM was utilized to check the elemental compositions. Samples for the complex permittivity and permeability measurement were fabricated by incorporating the CRH in paraffin wax with a weight fraction of 40 wt%. Then, the powder–wax composites were compressed into a 1.0 mm thickness of toroidal shape using a mold designed with an outer diameter of 7.0 mm and inner diameter of 3.0 mm. The complex permittivity and permeability were measured by utilizing a vector network analyzer  in the frequency range of 0.5–13.9 GHz. The reflection loss was calculated by using the measured complex permittivity and permeability.Figured = 0.35 nm, which is slightly larger than (002) plane of single crystal graphite (d = 0.335 nm), is shown in Figure d indicates the graphitized carbon is turbostratic carbon.d = 0.25 nm is corresponds to SiC.2).FE‐SEM image of the CRH1500 is depicted in µ′, imaginary: µ″) of the CRHs, in the range of 0.5–13.9 GHz are presented in FigureThe complex permittivity  and complex permeability  is given by the formular = ε′ – jε″, µr = µ′ – jµ″, f is the EM wave frequency (Hz), d is the thickness of the absorber (m), and c is the velocity of light in free space (m s−1). The R.L. of CRH800, CRH1500, and CRH2200 with weight fraction of 40 wt% and thickness, t = 1.0 mm is illustrated in Figure2 showed low R.L. of ≈−5.6 dB. Furthermore, CRH2200 which consists of graphitized carbon and mostly SiC particles showed slightly lower EM wave absorption performance and response bandwidth, with minimum R.L. of ≈−16.3 dB at 13.54 GHz and response bandwidth of 2.35 GHz. Notably, CRH heterogeneity which varied with carbonization temperatures are highly associated with the EM wave absorption performance.Based on the transmission line theory, the EM wave absorption performance was evaluated by calculating the reflection loss (R.L.) with the consideration of measured complex permittivity and permeability as followsThe CRH1500 are thinkable as a heterogeneous material, where graphitized carbon, SiC whiskers, and particles will stimulate additional dielectric relaxation by supplementary dielectric interfaces and higher polarization charges at the interface between those materials.tm = 1.6 mm demonstrated highest minimum R.L. of ≈−55.4 dB (>99.9997% absorption) at 11.37 GHz, with response bandwidth of 4.21 GHz. CRH1500 can be considered as the best EM wave absorber compared to other CRH samples, although CRH2200 showed wider response bandwidth of 5.12 GHz, considering CRH2200 tm = 2.7 mm which is almost double the tm of CRH1500. Furthermore, the dependence of CRH1500 R.L. with various thicknesses is shown in Figure The absorber's thickness is also a key factor that can influence the R.L. by relating to Equation In brief, heterogeneous materials including graphitized carbon, SiC whiskers, and particles were obtained through carbonization of RHs at 1500 °C. Their heterogeneity results in high interfacial polarization, which enhanced the EM wave absorption performance. CRH1500, 40 wt% with thickness of 1.6 mm revealed minimum R.L. of ≈−55.4 dB (>99.9997% absorption) at 11.37 GHz and response bandwidth of 4.21 GHz. Evidently, numerous factors such as type of filler, thickness, and heterogeneity, play a significant role towards the considerable EM wave absorption performance and response bandwidth.The authors declare no conflict of interest.SupplementaryClick here for additional data file.