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Deepwater bodies such as dam reservoirs are among the most prominent water resources that supply societies' water demand. Hence, water quality in these resources requires continuous and meticulous monitoring. This study evaluated the water quality of Changuleh Dam, a dam under construction in western Iran, using the CE‐QUAL‐W2 model to predict fluctuations in sulphate (SO42−) and hydrogen sulphide (H2S) concentrations. A sensitivity analysis was conducted to assess the dependence of model outputs on input variables. Additionally, an uncertainty analysis was performed using MATLAB to address the inherent uncertainties of the input variables through an ARIMA (2, 2, 1) time series model and Monte Carlo simulations. The results indicated a high sulphate concentration averaging 955.6 mg/l, considerably exceeding the drinking water standard of 400 mg/l, identifying the reservoir as a sulphate‐rich water resource. Seasonal fluctuations of H2S concentrations were also observed in the reservoir's anaerobic bed sediments, peaking at 87 mg/l. The sensitivity analysis showed that nitrate and total dissolved solids (TDS) varied more noticeably than dissolved oxygen (DO) at different depths, with the greatest variation at 50 m. This study highlights the critical need for continuous and meticulous monitoring of water quality in dam reservoirs to meet water supply standards. Highlights: Sulfate concentrations in the reservoir exceeded drinking water standards, averaging 955.6 mg/l.Hydrogen sulfide concentrations peaked at 87 mg/l during seasonal stratification.Sensitivity analysis revealed that nitrate and TDS were more impacted by input variations than dissolved oxygen.Uncertainty analysis indicated the greatest fluctuations in sulfate and hydrogen sulfide concentrations at a depth of 50 m.Aeration of the reservoir is recommended to reduce hydrogen sulfide levels and maintain water quality. [ABSTRACT FROM AUTHOR]

Relevance. Garlic is one of the most popular agricultural crops characterized by high nutritional value and unique chemical composition providing significant beneficial effect on human health.Methods. The review summarizes the most significant publications on garlic biochemical composition, utilization in medicine, human nutrition and agriculture for a period from 1988 to 2024 with the predominant utilization of Scopus and WoS publications.Results. The diversity of garlic processing products (fresh, dry powder, ‘Green' garlic, Laba garlic, garlic essential oil macerate, ethanolic extract (‘aged garlic extract' AGE) and black garlic) provides the diversity of biochemical composition and the direction of biological effect. The possibility to utilize both garlic bulbs, leaves, stems and peel in medicine and agriculture (for yield and stress resistance improvement) are the most important factors for successful waste free production and wide utilization of garlic.

In this study, E-nose and SPME-GC/MS were applied to compare the odour patterns and volatile compounds of two truffle species harvested in different areas of Campania (Southern Italy). In total, 107 Tuber mesentericum (black truffle) and 60 Tuber borchii (bianchetto truffle) truffles were sampled in areas of Avellino, Salerno, Benevento, and Caserta. The E-nose correctly discriminated between Tuber mesentericum and Tuber borchii truffles. The GC/MS analysis revealed qualitative-quantitative differences between Tuber mesentericum and Tuber borchii, with a prevalence of volatile phenols and aromatic compounds for the black truffle, which are responsible for smoky and floral aromas, and ketones, alcohols, aldehydes, and thiophene derivatives for the bianchetto truffle, mostly responsible for earthy mushroom- and garlic-like aromas. The discriminant analysis performed on the E-nose data pattern provided an average correct classification between 55 and 60% for the same species collected in different sites. Tuber borchii truffles were better discriminated based on the harvesting altitude (hilly and coastal areas). GC/MS revealed quantitative differences in the volatile compounds of truffles of the same species collected in different areas, with variations in abundance based on the harvesting site. The distinctive profile of volatile compounds could represent a useful chemical marker to be investigated to authenticate the truffle harvesting area. [ABSTRACT FROM AUTHOR]

Floral scent is a key olfactory cue in both diurnal and nocturnal pollination systems. In the case of nocturnal systems, such as bat‐pollinated flowers, odour seems to play a more important role than visual cues. Cactaceae include many bat‐pollinated species; however, few studies have investigated the olfactory cues in this family.We analysed and compared the chemical composition of the floral bouquet of three chiropterophilous cactus species, among which are a pair of congeners that differ considerably in scent intensity.Our research presents novel findings regarding the floral scent chemistry of chiropterophilous cactus species. We documented the first case of a bat‐pollinated cactus whose flowers lack perceptible floral scent and in which no volatile compounds were detected in our chemical analyses. Additionally, we provide a comprehensive analysis of the chemical composition of the floral bouquet of the other two bat‐pollinated species, revealing a resemblance among closely related species within the same genus.We highlight the need for further studies using biotests to investigate the mechanisms through which bats find flowers lacking scent. [ABSTRACT FROM AUTHOR]

The synthesis of pure phase Cu3SnS4 is of great significance for improving its material properties. Here, the control law of Cu and Sn element ratio on the synthesis of pure phase Cu3SnS4 from physical and chemical methods was analyzed through literature research. The results: (1) the adjustment of the Cu‐to‐Sn ratio metal elements as a phase control parameter has the characteristics of flexibility and controllability. (2) When the precursor component is rich in Cu and the chemical potential of the medium and high sulphur is high, the phase will develop to a wider thermodynamically stable region of Cu3SnS4. By adjusting the Cu‐to‐Sn ratio elements, when the release rate of anions and the reaction rate of cations adapt to each other, the thermodynamic reaction conditions can be well satisfied, which is beneficial to the preparation of pure phase Cu3SnS4. (3) The phase control method of Cu and Sn element ratio of template seed crystal can not only realize the reasonable regulation of Cu and Sn element ratio but also control the synthesis of phase more accurately. The results of this paper have certain reference values for the application of new materials synthesized by adjusting the proportion of elements. [ABSTRACT FROM AUTHOR]

Abstract The synthesis of pure phase Cu3SnS4 is of great significance for improving its material properties. Here, the control law of Cu and Sn element ratio on the synthesis of pure phase Cu3SnS4 from physical and chemical methods was analyzed through literature research. The results: (1) the adjustment of the Cu‐to‐Sn ratio metal elements as a phase control parameter has the characteristics of flexibility and controllability. (2) When the precursor component is rich in Cu and the chemical potential of the medium and high sulphur is high, the phase will develop to a wider thermodynamically stable region of Cu3SnS4. By adjusting the Cu‐to‐Sn ratio elements, when the release rate of anions and the reaction rate of cations adapt to each other, the thermodynamic reaction conditions can be well satisfied, which is beneficial to the preparation of pure phase Cu3SnS4. (3) The phase control method of Cu and Sn element ratio of template seed crystal can not only realize the reasonable regulation of Cu and Sn element ratio but also control the synthesis of phase more accurately. The results of this paper have certain reference values for the application of new materials synthesized by adjusting the proportion of elements.

The electrochemical features of the interactions of sulfur- and iron-containing compounds (ferrous sulfate, elemental sulfur, pyrite tailings, cysteine, sodium thiosulfate) with a model acidophilic consortium, including the genera Leptospirillum, Sulfobacillus, Acidithiobacillus, Ferroplasma, and Acidiplasma, were studied. The method of cyclic voltammetry recorded redox processes at the electrode/solution interface in the presence of the studied sulfur- and iron-containing compounds. In general, the modeling consortium led to the intensification of these processes. The characteristics of the diffuse layer near the electrode/solution interface were studied using electrochemical impedance spectroscopy. The introduction of microorganisms and/or substrates into the supporting electrolyte led to a decrease in the slope and can be interpreted as evidence of their effect on the diffusion part of the double layer. Its contribution decreases in favor of ion transport. All this, in general, does not contradict the assumption of cell adsorption on the electrode surface. Confocal laser scanning microscopy confirmed this assumption and showed cell adhesion to the surface. The data obtained confirm the importance of bioelectrochemical processes of the studied group of microorganisms in biotechnological processes associated with the leaching of metals from sulfide ores. [ABSTRACT FROM AUTHOR]

Graphene oxide (GO) and graphene oxide/bioactive agent dispersions were deposited on a cotton fabric and then chemically reduced at 90°C for 40 min using dyeing technique. As the reducing agents the compounds containing sulphur: sodium hydroxymethanesulfinate and to compare sodium hydrosulfite, widely applied in the textile industry, were used. The one-step process of the GO reduction imparted electrical conductivity, hydrophobic properties (water contact angle of approx. 130°) and in the presence of bioactive agents (bis(2-pyridylthio)zinc 1,1'-dioxide dispersion or dimethyltetradecyl [3-(trimethoxysilyl)propyl] ammonium chloride) bioactive properties to the cotton fabric. After chemical reduction of GO the surface resistance value was on the order of 103-104 Ω, whereas after reduction of GO in the presence of the bioactive agents the increase in surface resistance value of the cotton fabric by one order of magnitude was observed. The advantage of the dyeing technique to GO reduction on the surface of cotton fibres is that it does not deteriorate the strength properties of the fabric. In addition, the possibility of reducing GO with the use of devices and auxiliary agents commonly used in the textile industry is of particular importance in economic and ecological terms. [Display omitted] [ABSTRACT FROM AUTHOR]

Garlic is one of the most important vegetables and used for nutrient and medicinal purposes since ancient times. Deficiency in the detection of high-quality garlic genotypes with a rich biochemical profile is one of the main constraints in limiting the production. Currently, the selection and identification of promising garlic genotypes is a popular target, and to reach the best results it is necessary to clarify discrimination. This study aims to discriminate the garlic genotypes obtained from different cultivation locations in Turkey. For that purpose, firstly, morphological characters including biometric parameters were measured based on 18 morphological traits. Particular correlations related to the biometric parameters were calculated. Secondly, a total of 41 main volatiles in the bulbs of garlic genotypes were identified by using headspace-gas chromatography/mass spectrometry. Multivariate discriminant analyses including two-way hierarchical clustering analyses (HCA) and canonical discriminant analysis (CDA) were used to identify dependencies between garlic genotypes and to distinguish the differences based on volatiles among genotypes. There proved to be significant variability in the Turkish genotypes for the morphologic descriptors and the results suggest that besides cultivation area, environmental conditions affect the formation of differentiation in garlic genotypes. Multivariate analysis revealed two main groups, and variation in volatiles within genotypes was important. The closest relationship was determined in the genotypes collected from Araban (district of Gaziantep), Kahramanmaraş, and Yavuzeli (district of Gaziantep) region of Turkey based on the volatiles. The results of volatiles also indicate that the genotypes collected from Kilis, Kastamonu, and Tokat provinces of Turkey could be potential for a promising source related to volatile compounds. The current study established a foundation for the assessment of Turkish garlic genotypes for using in a breeding program and promoting commercialization. [ABSTRACT FROM AUTHOR]

Background/purpose: Halitosis is the unpleasant and offensive odour in exhaled air, which is linked to the presence of volatile sulphur compounds (VSC). Different mouthwashes have been used to treat halitosis. The objective of this study was to test the effect of an antioxidant (AO) mouthwash, and mouthwash containing [0.05% chlorhexidine, 0.05% cetylpyridinium chloride, and 0.14% zinc lactate (CHX-CPC-Zn)] on VSC. Material and methods: Thirty-five subjects with halitosis participated in this clinical trial. At the baseline visit, a breath sample was taken and analyzed for the level of hydrogen sulphide (H2S), methyl mercaptan (CH3SH), and dimethyl sulphide (CH3SCH3) using portable gas chromatography (OralChroma™). Two mouthwashes were randomly provided to each subject in addition to saline solution (NaCl 0.9%) as control. Subjects were instructed to rinse with 20 ml of the mouthwash for 1 min twice daily for 2 weeks. At second visit, post-treatment breath sample was taken. Afterward, the patient was asked to refrain from using mouthwash for a washout period of 1 week. A similar procedure was repeated for each mouthwash interval. Results: No significant differences in VSC level between all three groups were detected at baseline. A significant reduction in VSC level was obtained after using CHX-CPC-Zn mouthwash. On other hand, both AO mouthwash and saline had no significant impact on the level of VSC. Conclusion: CHX-CPC-Zn mouthwash has a significant effect on VSC level reduction in subjects with confirmed halitosis. Besides, using AO mouthwash regularly for 2 weeks did not have any impact on improving the level of halitosis.

The aim of the study was to assess the impact of the duration of the use of a biofiltration bed on the efficiency of biofiltration of sulphur compounds and on the physicochemical and microbiological properties of the bed. The study was carried out at an animal waste treatment plant. Two biofiltration chambers (beds A and B) filled with different organic mixtures (compost soil, peat, coconut fibre and oak bark) were used in the biofilter. Chromatographic analysis showed a very high rate of effectiveness in the first study period, irrespective of the packaging material used. The best effects were obtained for inorganic sulphur compounds (above 99%). The duration of use of the bed material was shown to affect the efficiency of biofiltration. After 3 years of operation, thiol degradation efficiency fell below 50%. The biological decomposition of inorganic compounds (H2S + SO2) was 73% and 59.6% in beds A and B, respectively. Analysis of the biofiltration material indicated stabilization of its physicochemical parameters. Numbers of bacteria were not found to be depend on the duration of use or the type of filtering media.

The efficiency of hydrogen peroxide in the regeneration of dimethyl sulphide (DMS) exhausted-activated carbons (ACs) is assessed in this study. Moreover, the influence of chemical surface composition is evaluated using six ACs (two commercial ACs and four chemically modified ACs) with different surface features. Chemical surface composition of ACs before and after different adsorption-regeneration cycles is assessed by temperature-programmed desorption coupled with mass spectroscopy (TPD-MS) and by diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS). Results reveal that up to a 60% of regeneration efficiency is attained, being more effective in the presence of ACs derived from Filtrasorb 300 AC sample. Experimental findings show that ACs with high content of basic oxygen–containing functional surface groups and mineral fraction are responsible to promote the catalytic decomposition of hydroxide peroxide, leading to a higher formation of hydroxyl radicals and to the observed increase in the regenerative oxidation of adsorbed DMS. However, a decrease in removal efficiency is related to an increase in the amounts of oxygen functionalities mainly in the form of strong acidic surface groups such as carboxylic acid anhydrides and carboxylic acids that shift the reaction mechanism from promoting the initiation of radical chain reactions to termination. Additionally, DRIFTS analyses indicate that after successive adsorption-regeneration cycles the fraction of organic molecules that remains adsorbed limits the access to active surface sites responsible for radical generation, reducing drastically the catalytic activity of ACs. [Display omitted] [ABSTRACT FROM AUTHOR]

The presence of organosulphur compounds in middle distillate fuels not only leads to air pollution, but they are also a poison to catalytic converters, soot traps and other harmful emission control technologies. A method has been developed for purification of sulphur compounds from diesel fraction from atmospheric distillation by extraction with N-methyl pyrrolidone, furfural and diethylene glycol. The experiment processes at different duration (from 90 to 360 min) and ratio of gas oil fraction:solvent (1:1 and 1:2) show that these methods could be used to reduce the sulphur content in diesel fractions more than twice. The best result was obtained with N-methyl pyrrolidone. The activity coefficients of the raffinate and the extract, the selectivity and the product of the selectivity with the square of the activity coefficient of the raffinate for the solvents are calculated and can be used as an indicative criterion for efficiency in the selection of selective solvents and their comparison. It can be concluded that as the amount of solvent and the contact time increase, the values of the coefficients decrease in direct proportion, which indicates a better selectivity of the process. [ABSTRACT FROM AUTHOR]

Monitoring the condition of building structures based on composite materials in aggressive environments shows that the deterioration of basic properties occurs under the influence of various factors such as temperature and humidity changes, in addition to changes in the chemical composition of air environment. In addition, the composite materials during the operation must retain not only the mechanical properties laid down at the design stage, but also the electro-physical characteristics, regardless of the type of destructive effects. In the current study, the quantitative assessment of the result of the interaction of an aggressive sulphate-containing medium with composites modified with conductive and dielectric additives was carried out. The effect of sulphate attack on the specific electrical conductivity of cement composites was studied. The nature of the interaction was evaluated by changing the properties of the samples of the developed compositions under the influence of a single-normal solution of sodium sulphate. The analysis was carried out by means of potentiometric titration using the exchange interaction method by fixing the degree of absorption of sulphate ions and determining the concentration of calcium ions in the solution. The measurement of the solution potential allowed determination of the quantitative indicators of the rate of calcium hydroxide leaching from the sample structure, which is necessary to assess the intensity of the destruction process and determine the nature of the change in strength properties. Measurements of the electrical resistivity of samples under the constant influence of sulphate aggression were taken during 28 days of observation. A method for quantifying the effect of a sulphate medium on a cement matrix was proposed that enables the material durability to be predicted. The features of changes in the morphology of structural components after exposure to aggressive solution were determined by physical and chemical methods. [ABSTRACT FROM AUTHOR]

Metals play an important role in various metabolic activities in the human body, but above desired concentrations, a role reversal occurs that causes deadly outcomes viz., cancer. Metals cannot be cracked down and are non-biodegradable. It is the bioaccumulation of toxic metals inside the biomatrices, that further intensifies the research on different means of metal detoxification from different matrices. Among heavy toxic metals lead is a brutal carcinogen that requires pitiless sensors for its capturing. The use of heterocycles for metal sensing in supramolecular chemistry is preferred due to the strong chelation they offer to toxic metals. The C1-C3 probes were synthesized and studied for their Pb2+ binding ability. All the probes were prepared by treating bromoacetyl coumarin with camphor sulphonamide, 5-dimethylamino-1-naphthalene sulphonamide, and methyl-2-amino-sulphonyl benzoate at room temperature. The probes show selective binding with Pb2+ ions in aqueous acetonitrile among different tested metal ions viz., Cu2+, Zn2+, Ni2+, Mn2+, and Pb2+ ions as shown in ultraviolet (UV)-visible, nuclear magnetic resonance (NMR), and high-performance liquid chromatography (HPLC) studies. These sulphur-containing probes bind very well with Pb2+ ions by offering selectivity in binding positions that capture lead ions at their minimum possible concentration. [ABSTRACT FROM AUTHOR]

This study investigated the compositional changes in broccoli (Brassica oleracea L. var. italica) and cauliflower (Brassica oleracea L. var. botrytis) landraces during a four-year breeding program in organic farming, focusing on key bioactive compounds linked to value for cultivation and use (VCU). Our results revealed that many metabolites, notably ascorbic acid, nitriles, sulphides, and total phenols, significantly responded to environmental differences, particularly higher temperatures, and reduced rainfall during plant development. Other traits, like sugar levels, sulforaphane, indole-3-carbinol, and pigments showed stable genetic control and limited variation. This work provides valuable insights for the development of innovative and high VCU material tailored to organic cropping systems and potentially leading to improved final product quality. • Cross-composite Brassica populations are a valuable agrobiodiversity source. • Brassica spp. phytochemicals were measured during four years of organic breeding. • Sugars, sulforaphane, indol-3-carbinol and pigments, resulted under genetic control. • Ascorbic acid, phenols and VOC were influenced by the year of breeding. [ABSTRACT FROM AUTHOR]

Garlic (Allium sativum L.) is one of the most valuable plants in the world because it contains important substances with protective and healing effects on human health. Its health-promoting effects have been already known in ancient Egypt, China, Greece and also the Romans used it. Many studies have shown that garlic can help from colds, coughs, flu, pulmonary diseases, clean blood vessels, lowers blood pressure and cholesterol and has antibacterial, antiviral, anti-carcinogenic, anti-mutagenic and antioxidant properties. Garlic contains antioxidant that support the body´s defense mechanism against oxidative damage. The physiological effect of garlic can be affected by sulphur – containing compounds as well as other biologically active compounds such as polyphenols (mainly flavonoids), minerals (Ca, Fe, I, K, Mg, Na, Zn) and vitamins (A, B1, B2, B6, C). The main sulphur compound in garlic is alliin, converted to allicin by the enzyme alliinase, which results in a characteristic garlic aroma and taste.

The presence of organosulphur compounds in middle distillate fuels not only leads to air pollution, but they are also a poison to catalytic converters, soot traps and other harmful emission control technologies. Reducing the sulphur content of diesel fuels to ultra-low levels of the order of 10 ppm plays a key role in significantly reducing emissions. Achieving ultra-low sulphur levels in diesel fuels is known to be a major challenge for modern oil refining worldwide. In present paper is investigated application of adsorption approaches towards reducing sulphur compounds in middle distillate fractions. [ABSTRACT FROM AUTHOR]

Halitosis is the unpleasant and offensive odour in exhaled air, which is linked to the presence of volatile sulphur compounds (VSC). Different mouthwashes have been used to treat halitosis. The objective of this study was to test the effect of an antioxidant (AO) mouthwash, and mouthwash containing [0.05% chlorhexidine, 0.05% cetylpyridinium chloride, and 0.14% zinc lactate (CHX-CPC-Zn)] on VSC. Thirty-five subjects with halitosis participated in this clinical trial. At the baseline visit, a breath sample was taken and analyzed for the level of hydrogen sulphide (H 2 S), methyl mercaptan (CH 3 SH), and dimethyl sulphide (CH 3 SCH 3) using portable gas chromatography (OralChroma™). Two mouthwashes were randomly provided to each subject in addition to saline solution (NaCl 0.9%) as control. Subjects were instructed to rinse with 20 ml of the mouthwash for 1 min twice daily for 2 weeks. At second visit, post-treatment breath sample was taken. Afterward, the patient was asked to refrain from using mouthwash for a washout period of 1 week. A similar procedure was repeated for each mouthwash interval. No significant differences in VSC level between all three groups were detected at baseline. A significant reduction in VSC level was obtained after using CHX-CPC-Zn mouthwash. On other hand, both AO mouthwash and saline had no significant impact on the level of VSC. CHX-CPC-Zn mouthwash has a significant effect on VSC level reduction in subjects with confirmed halitosis. Besides, using AO mouthwash regularly for 2 weeks did not have any impact on improving the level of halitosis. [ABSTRACT FROM AUTHOR]

The essence of the mathematical model of disconnectors' multiple reignition arc is the repeated breakdowns of SF6. In this study, the kinetic properties of microparticles are studies based on the streamer discharge theory, and a fluid arc mathematical model applied in centimetre clearance is established. Ultra‐High Voltage (UHV[AQ ID=Q1]) disconnector manufactured by Pingao Electric Co. Ltd of Henan Province is selected as the object and the resistance change process of contact clearance multiple reignition arc is simulated by finite difference method‐finite element method‐flux corrected transport self‐programming in MATLAB based on the chamber structure and operating characteristics. UHV gas‐insulated switchgear very fast transient overvoltage (VFTO) test platform is built to gain the characteristics of VFTO waveforms generated by the disconnector's operation. Compared with simulation results, the test data shows that the fluid arc mathematical model can scientifically explain the dynamic development process of microparticles in the contact clearance and the calculation results are consistent with the test data. In addition, the arc fluid mathematical model combines the structure and operating characteristics of the switch with the development process of microparticles, which can better guide the design of the switch, and provide a theoretical basis for the suppression of VFTO with the disconnector itself. [ABSTRACT FROM AUTHOR]

Monitoring the condition of building structures based on composite materials in aggressive environments shows that the deterioration of basic properties occurs under the influence of various factors such as temperature and humidity changes, in addition to changes in the chemical composition of air environment. In addition, the composite materials during the operation must retain not only the mechanical properties laid down at the design stage, but also the electro-physical characteristics, regardless of the type of destructive effects. In the current study, the quantitative assessment of the result of the interaction of an aggressive sulphate-containing medium with composites modified with conductive and dielectric additives was carried out. The effect of sulphate attack on the specific electrical conductivity of cement composites was studied. The nature of the interaction was evaluated by changing the properties of the samples of the developed compositions under the influence of a single-normal solution of sodium sulphate. The analysis was carried out by means of potentiometric titration using the exchange interaction method by fixing the degree of absorption of sulphate ions and determining the concentration of calcium ions in the solution. The measurement of the solution potential allowed determination of the quantitative indicators of the rate of calcium hydroxide leaching from the sample structure, which is necessary to assess the intensity of the destruction process and determine the nature of the change in strength properties. Measurements of the electrical resistivity of samples under the constant influence of sulphate aggression were taken during 28 days of observation. A method for quantifying the effect of a sulphate medium on a cement matrix was proposed that enables the material durability to be predicted. The features of changes in the morphology of structural components after exposure to aggressive solution were determined by physical and chemical methods.

Fluorinated nitrile (C(4)F(7)N) gas mixture has been introduced as the most promising candidate to replace sulfur hexafluoride using in gas-insulated equipment. In this study, the authors explored the influence of oxygen on the dielectric and decomposition properties of C(4)F(7)N–CO(2)–O(2) gas mixture. The authors found that the dielectric strength of the C(4)F(7)N–CO(2)–O(2) gas mixture with 2, 4, 6, 8 and 10% O(2) was increased by 4.85%, 6.49%, 7.70%, 3.21% and 2.74% compared with C(4)F(7)N–CO(2). The addition of 2–6% O(2) to the C(4)F(7)N–CO(2) gas mixture could effectively reduce the content of most of the decomposition by-products such as CF(4), CO, C(2)F(6), C(3)F(6), C(3)F(8), CF(3)CN, C(2)F(5)CN, (CN)(2). While high content of oxygen (>6%) results in higher decomposition of C(4)F(7)N, which has a negative effect on the stability of C(4)F(7)N gas mixture. Generally, it is recommended to add 2–6% O(2) in the C(4)F(7)N–CO(2) gas mixture to improve its insulation properties as well as inhibit the decomposition of C(4)F(7)N in the discharge for medium-voltage engineering application.

In the long-running of sulphur hexafluoride (SF(6))-insulated equipment, SF(6) inevitably decomposes to various decomposition products under electric discharge, including SOF(2) and SO(2)F(2). In this work, single Pt modified molybdenum disulphide (Pt-MoS(2)) monolayer, and double Pt modified molybdenum disulphide (Pt(2)-MoS(2)) monolayer are proposed to analyse its adsorption and sensing properties to SOF(2) and SO(2)F(2) with single and double gas molecules adsorption based on density functional theory. The adsorption energy, density of states, and molecular orbit theory are employed to analyse the adsorption and sensing mechanism. It turns out that the Pt-MoS(2) and Pt(2)-MoS(2) present outstanding adsorption capacity to gas molecules. Specifically, double SOF(2) adsorption on Pt(2)-MoS(2) shows the best adsorption performance, and the conductivity of the adsorption system changes the most in the adsorption process. Overall, both Pt-MoS(2) and Pt(2)-MoS(2) perform as an excellent gas sensor. This study provides a theoretical basis to develop Pt-MoS(2) and Pt(2)-MoS(2) based materials for SOF(2) and SO(2)F(2) detection in SF(6)-insulated equipment.

SF(6) has been widely used as an insulating and arc extinguishing medium in electric power equipments. Detection of gas decomposition products is an important means for condition monitoring and fault diagnosis. Trace H(2)O and O(2) have a significant influence on the species and concentrations of SF(6) decomposition products. It is important to explore the influence mechanism of trace H(2)O and O(2) on SF(6) decomposition products under arcing conditions. A series of SF(6) decomposition tests were carried out on a 40.5kV SF(6) circuit breaker, and a gas chromatograph and an electrochemical sensor were used to measure decomposed components. First, the H(2)O content remained constant, and the O(2) content and arcing energy changed in the tests. It has been found that the decomposition products of SF(6) are SOF(2), SO(2), CO, CO(2), CF(4), C(2)F(6) and C(3)F(8). Then, the O(2) content remained constant, and the H(2)O content changed. The decomposition products are mainly SOF(2), SO(2), CO and CO(2). Concentrations of all these decomposition products increase first and then tend to be stable slowly over time, but change differently with the increase of H(2)O and O(2) contents, because H(2)O and O(2) play different roles in the formation process of each decomposition characteristic components.

The extraction process of gasoil fraction was investigated and thermodynamic and kinetic parameters of the process were determined. Activation thermodynamic parameters (free molar energy, entrophy, enthalphy and equilibrium constant) of the transition state were obtained for sulphur and arene compounds extraction, respectively. The calculated kinetic process parameters were: reaction rate constants, reaction order and degree of extraction. [ABSTRACT FROM AUTHOR]

Purifying of gasoil fraction by solvent extraction was investigated. The thermodynamic and kinetic parameters of the process were determined. Activation thermodynamic parameters as free molar energy (Gibbs energy), entropy, enthalpy and equilibrium constant were obtained for raffinates, respectively. The calculated kinetic process parameters were activation energy, Arrhenius constant and reaction rate constant. [ABSTRACT FROM AUTHOR]

Onion (Allium cepa L.) is a very important vegetable crop cultivated worldwide. The bulb is a major source of phytochemicals useful for human health and rich in sulphur compounds responsible for their typical odour and flavour. In this study, we investigated the volatile compounds and biochemical properties besides the antimicrobial activity of onion Montoro and Alife varieties, and of two ecotypes of Vatolla variety (spinning top and tapered shape), cropped in the southern Mediterranean area (Italy). For all investigated onions, the organosulphur compounds, mainly di- and trisulfides, are the most abundant compounds. Alife variety showed higher polyphenols amount (8.2 GAE mg/g dw) with respect to the lowest one (3.9 GAE mg/dw g) in spinning top Vatolla, as well as an higher antioxidant activity (42.37 µmol TE/g dw) about two-fold higher than those detected in the other varieties. All the onions showed low pungency level, confirming their popular classification as a sweet onion. The total content of soluble sugars ranged from 461 to 624 mg/g dw; malic acid was the major organic acid in Alife and Montoro varieties instead for both Vatolla ecotypes citric acid was the most abundant ones. The biochemical characterization highlighted the three onion varieties as a good source of bioactive compounds. The antimicrobial activity of the onion extracts pointed out an effective action against three Gram-positive species (B. cereus, L. innocua, S. aureus) and P. aeruginosa; consequently, they could represent a new source of natural antimicrobial agents. [ABSTRACT FROM AUTHOR]

Summary: Volatile emissions may play a key role in structuring pollination systems of plants with morphologically unspecialised flowers. Here we test for pollination by small mammals in Eucomis regia and investigate whether its floral scent differs markedly from fly‐ and wasp‐pollinated congeners and attracts mammals.We measured floral traits of E. regia and made comparisons with insect‐pollinated congeners. We observed floral visitors and examined fur and faeces of live‐trapped mammals for pollen. We determined the contributions of different floral visitors to seed set with selective exclusion and established the breeding system with controlled pollination experiments. Using bioassays, we examined whether mammals are attracted by the floral scent and are effective agents of pollen transfer.Eucomis regia differs from closely related insect‐pollinated species mainly in floral scent, with morphology, colour and nectar properties being similar. We found that mice and elephant‐shrews pollinate E. regia, which is self‐incompatible and reliant on vertebrates for seed production. Mammals are strongly attracted to the overall floral scent, which contains unusual sulphur compounds, including methional (which imparts the distinctive potato‐like scent and which was shown to be attractive to small mammals).The results highlight the important role of scent chemistry in shifts between insect and mammal pollination systems. [ABSTRACT FROM AUTHOR]

SF6 has been widely used as an insulating and arc extinguishing medium in electric power equipments. Detection of gas decomposition products is an important means for condition monitoring and fault diagnosis. Trace H2O and O2 have a significant influence on the species and concentrations of SF6 decomposition products. It is important to explore the influence mechanism of trace H2O and O2 on SF6 decomposition products under arcing conditions. A series of SF6 decomposition tests were carried out on a 40.5kV SF6 circuit breaker, and a gas chromatograph and an electrochemical sensor were used to measure decomposed components. First, the H2O content remained constant, and the O2 content and arcing energy changed in the tests. It has been found that the decomposition products of SF6 are SOF2, SO2, CO, CO2, CF4, C2F6 and C3F8. Then, the O2 content remained constant, and the H2O content changed. The decomposition products are mainly SOF2, SO2, CO and CO2. Concentrations of all these decomposition products increase first and then tend to be stable slowly over time, but change differently with the increase of H2O and O2 contents, because H2O and O2 play different roles in the formation process of each decomposition characteristic components. [ABSTRACT FROM AUTHOR]

Garlic (Allium sativum L.) is the most important species of the Allium genus and an important vegetable crop throughout the world. Garlic is widely used as an obligatory part in many cooked dishes. It is one of the ancient plants playing one of the most important dietary and medicinal roles in human beings for centuries. Garlic possess many therapeutic properties including antimicrobial, antiviral, antifungal, cardioprotective, neuroprotective, anticarcinogenic, antimutagenic, anti-hypertensive, anti-diabetic and antioxidant. This study has focused on the comparison of the total polyphenols content, the total sulphur content and antioxidant activity of the studied varieties of garlic in the area of Nitra, Slovak Republic. The analyzed samples of garlic were collected at the stage of full maturity. TPC was measured using the spectrophotometric method of Folin-Ciocalteu agents. TPC in studied varieties of garlic were determined in the range 742 mg.kg-1 (Mojmír) to 635 mg.kg-1 (Makoi). The determination of the total sulfur content was based on dry combustion in the presence of oxygen and allows for the quantitative conversion of sulfur to SO2. Statistically significant highest level of TSC recorded in 0.751% (Mojmír) and the lowest level was in 0.523% (Makoi). Antioxidant activity was determined by the spectrophotometric method using a compound DPPH (2.2-diphenyl-1-picryhydrazyl). The highest value of AA was measured in Mojmír (17.7%). The lowest level was observed in Makoi (12.4%). In all studied samples of garlic was confirmed by the strong dependence of the total polyphenols content, total sulfur content and antioxidant activity. [ABSTRACT FROM AUTHOR]

Allium sativum (garlic) is widely known and is consumed as a natural prophylactic worldwide. It produces more than 200 identified chemical compounds, with more than 20 different kinds of sulfide compounds. The sulfide compounds particularly are proven to contribute to its various biological roles and pharmacological properties such as antimicrobial, antithrombotic, hypoglycemic, antitumour, and hypolipidemic. Therefore, it is often referred as disease-preventive food. Sulphur-containing compounds from A. sativum are derivatives of S-alkenyl-l-cysteine sulfoxides, ajoene molecules, thiosulfinates, sulfides, and S-allylcysteine. This review presents an overview of the water-soluble and oil-soluble sulphur based phytochemical compounds present in garlic, highlighting their mechanism of action in treating various health conditions. However, its role as a therapeutic agent should be extensively studied as it depends on factors such as the effective dosage and the suitable method of preparation.

The refractory preheating process in oxygen furnaces is a dynamic input of energy in a chemically complex system requiring special attention to chemical emissions relative to permissible release limits. This particular industrial and regulatory interest is the emission of volatile organic compounds (VOC), given their detrimental impacts on human health. In the present work, a mathematical model was developed to predict the emission rates of volatile organics during the preheating of a 260-ton basic oxygen furnace. A numerical heat transfer model was developed using finite difference techniques to obtain the thermal profile and then integrated with chemical thermodynamics using FactSage 7.0 (CRCT, Polytechnique Montreal Quebec Canada, H3C 3A7). The parameters that affected VOC emissions were preheating process times, burner gas composition, heating rate, and burner geometry. Two different preheating procedures were compared, and emission rates were predicted with extended use of a top burner providing the greatest degree of emissions control. The mathematical model was validated against plant data with respect to average emission rates of CO, CO2, SOX, and NOX.

This study was designed to determine the chemical composition, antioxidant activity, and selected bioactive compound content and occurrence in whole immature and mature garlic plants grown from air bulbils. Two winter garlic cultivars, Harnaś and Ornak, of Polish origin, were cultivated from air bulbils at the Experimental Station of the Agricultural University in Kraków, Poland. Harvest bunching of garlic of both cultivars was carried out in May and in June. Mature plants were harvested in July. In whole plant proximate analysis, the concentration of vitamin C, total polyphenols, antioxidant activity, carotenoids, chlorophyll a and b, as well as glutathione level were determined. P-coumaric acid was found in Harnaś and Ornak samples collected in May. Sinapinic acid was identified in Ornak samples collected in June and July. Identification of sulphur compounds depended on the term of harvesting. Significantly higher content of total phenolic compounds, antioxidant activity, as well as other bioactive compounds, was measured in the Harnaś and Ornak cultivars harvested in May. A significantly lower level of bioactive compounds was determined in mature plants harvested in July. The organosulfur compound profile and polyphenolic profile depended on the time of harvesting. Immature garlic cultivated from air bulbils is recognized as a potential source of bioactive compounds in human nutrition, however, more research, in particular in vivo studies, is required to confirm its functional properties.

Estimates of the sea-to-air flux of dimethylsulfide (DMS) are based on sea surface concentration measurements and gas exchange calculations. Such calculations are dependent on the diffusivity of DMS (DDMS), which has never been experimentally determined. In this study the diffusivity of DMS in pure water was measured over a temperature range of 5°–30°C. The measurements were made using a dynamic diffusion cell in which the diffusing gas flows over one side of an agar gel membrane and the inert gas flows over the other side. The diffusion coefficient can be estimated from either time dependent or steady state analysis of the data, with an estimated uncertainty of less than 8% (1σ) in each measurement. A best fit to all the experimental results yields the equation DDMS (in cm2 sec−1) = 0.020 exp (−18.1/RT), where R = 8.314 × 10−3 kJ mole−1 K−1 and T is temperature in kelvin. The values of DDMS obtained in this study were 7–28% larger than estimates from the empirical formula of Hayduk and Laudie (1974) which has previously been used for DMS in gas exchange calculations. Applying these values to seawater results in an increase of less than 5% in the global oceanic flux of DMS.

Electric power industry is extensively using gas-insulated systems for the transmission and distribution of electrical energy. In high-voltage technology, the gas insulation is dominated by Sulphur-hexafluoride (SF(6)) since the early 60th. It is a greenhouse gas and has long atmospheric lifetime. This paper proposes comparatively more environmental friendly R410 gas as an alternative to SF(6) for high-voltage applications. To validate the performance and theoretical concepts, it has been analysed experimentally. Buffer gases air and carbon dioxide were mixed with the base gas R410A to reduce the liquification temperature and global warming potential. Dielectric strength of R410A was tested for DC as well as AC voltage, results were compared with that of SF(6) and other alternatives available in literature, and the results were comparable. Insulation self-recoverability test of R410A was performed and the synergistic effect of the mixed gases was calculated. Consequently, this work has discovered that R410A is the suitable alternative to SF(6) for high-voltage applications.

Garlic (Allium sativum L.) is highly regarded throughout the world for both its medicinal and culinary properties. With its bioactive compounds and sulphur containing compounds, high trace mineral content, garlic has shown anti-viral, anti-bacterial, anti-fungal and antioxidant abilities. This work has focused on the measurement and comparison of the total polyphenols content, the total sulphur content and antioxidant activity of the studied varieties of garlic in the area of Nitra and Bardejov, Slovak Republic. The highest content of monitored indicators (TPC, TSC, AOA) was measured in the area of Nitra. TPC was determined using the spectrophotometric method of Folin-Ciocalteu agents. The total polyphenols content were determined in the range 621.13 to 763.28 mg kg-1 in area of Nitra. The content of total sulphur compounds in the area of Nitra ranges from 0.562 to 0.800 % and in the second area ranges from 0.421 % to 0.658 %. Antioxidant activity was measured by the spectrophotometric method using a compound DPPH. The value of antioxidant activity ranged from 12.01 % to 20.22 % in both monitored locations. The content of TPC, TSC and AOA beside the variety may be affected by the localitylinked factors like climatic conditions and the agrochemical composition of the soil.

The authors report quartz crystal microbalance (QCM) integrated with hexagonal boron nitride–graphene (hg) monolayer heterostructure as a sensor to detect mass flow of sulphur hexafluoride (SF6), an important electrical insulating gas, under humid conditions. Their recent work demonstrated an enhancement in QCM sensing characteristics upon attaching monolayer 2D materials onto the QCM electrode surface and its application for improved relative humidity measurement. Here, they extend this approach to detect flow of SF6 gas causing variation in relative humidity. They fabricated a hg-QCM sensor by transferring the heterostructure thin film onto the QCM electrode surface using a standard wet transfer technique and measured return loss of the QCM under SF6 gas flow at a selected RH condition. The mass flow of the humid SF6 gas effects perturbation in damping at the QCM surface as indicated by changes in the motional resistance of the QCM. The motional resistance changes introduced significant variation in loaded Q-factor, the magnitude of which was gas species-dependent, thus allowing to distinguish SF6 from other common electronics gases. [ABSTRACT FROM AUTHOR]

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Copyright of Acta Agriculturae Slovenica is the property of Biotechnical Faculty of the University of Ljubljana and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Conventional diesel‐electric propulsion systems in platform supply vessels (PSVs) use low‐voltage AC (LVAC) supply‐based architecture with multiple diesel‐generators feeding busbars at 690 V, 60 Hz. The busbars distribute power to thruster motor drives via multi‐pulse transformers and diode bridge rectifiers. Advancements in electrical power conversion and distribution technologies offer possibilities of AC or DC distribution at low/medium voltage (LV/MV) for reduced fuel consumption (FC), emissions, and equipment footprint. This study presents methodology to qualify propulsion system architecture for PSV application. Potential architectures, besides conventional one, are active front end (AFE) converter‐based LVAC (690 V), MVAC (3.3 kV), LVDC (1000 V), and MVDC (5000 V). Performances of these architectures are assessed quantitatively based on FC, emissions, weight, volume, efficiency, and reliability. FC is estimated based on brake‐specific FC data of diesel engine. NOx, SO2, and CO2 emissions are assessed based on their emission factors. The weight, volume, and efficiency are estimated based on parameters of individual components. Reliability is assessed based on component failure data using DIgSILENT Power Factory. The architectures are ranked based on performance parameters using a Pugh matrix. The most suitable architecture for the target PSV is LVDC, followed by MVDC, LVAC with AFE, MVAC, and conventional LVAC. [ABSTRACT FROM AUTHOR]

SO2 is a symbolic gas that can indicate the insulation status of SF6 insulation electrical equipment. Its accurate quantitative measurement is of the great significance for the judgement of the type and severity of faults inside the insulation equipment. For this reason, a detection system of trace SO2 based on ultraviolet (UV) spectrometry was presented. The measured UV absorption spectra of SO2 were processed using the wavelet analysis to remove useless spectra information and get the UV differential absorption spectra of SO2. The fast Fourier transform (FFT) was used to analyse UV differential spectra in the band of 190–230 and 290–310 nm and extract the feature information. The results show that there is a good linear relationship between the FFT characteristic peak value and the concentration of trace SO2 in the two wave bands. The detection limit in the band of 190–230 nm was even lower than that in the band of 290–310 nm. Besides, the differential absorption cross section of SO2 decreases with the increase of temperature. The study has laid a foundation for the application of the UV differential absorption spectroscopy in the online monitoring and fault diagnosis of SF6 insulation electrical equipment. [ABSTRACT FROM AUTHOR]

SO2 is a symbolic gas that can indicate the insulation status of SF6 insulation electrical equipment. Its accurate quantitative measurement is of the great significance for the judgement of the type and severity of faults inside the insulation equipment. For this reason, a detection system of trace SO2 based on ultraviolet (UV) spectrometry was presented. The measured UV absorption spectra of SO2 were processed using the wavelet analysis to remove useless spectra information and get the UV differential absorption spectra of SO2. The fast Fourier transform (FFT) was used to analyse UV differential spectra in the band of 190–230 and 290–310 nm and extract the feature information. The results show that there is a good linear relationship between the FFT characteristic peak value and the concentration of trace SO2 in the two wave bands. The detection limit in the band of 190–230 nm was even lower than that in the band of 290–310 nm. Besides, the differential absorption cross section of SO2 decreases with the increase of temperature. The study has laid a foundation for the application of the UV differential absorption spectroscopy in the online monitoring and fault diagnosis of SF6 insulation electrical equipment. [ABSTRACT FROM AUTHOR]

Biological air cleaners used for reducing emissions of odorants are often challenged by the low solubility of reduced sulphur compounds. In a recent study high removal of hydrogen sulphide (∼75%) from the exhaust air from a pig house was achieved using a biofilter. The aim of this study was to investigate if this high removal could be due to the presence of fungi. The removal of reduced sulphur compounds in a 600-mm wide cellulose biofilter was measured at depths of 0, 200, 400 and 600 mm and the results compared with estimated fungal hyphae surface area per biofilm area. Over 19 months, removal of hydrogen sulphide was measured during periods with and without fungi. The results demonstrate a correlation between the fungal hyphae surface area and the removal of hydrogen sulphide with the highest removal in the first 200 mm of the biofilter and decreasing removal with depth. During periods with presence of fungi, the removal of hydrogen sulphide (64%) was significantly higher than during periods without fungi (18%). It is hypothesised that the observed fungi oxidise hydrogen sulphide and may play a major role in biofilters treating air from pig houses due to the expansion of the active surface area caused by the hyphae. [ABSTRACT FROM AUTHOR]

This is the first report describing an analytical method for quantitative analysis of two naturally occurring sulphur compounds, S-methyl-l-cysteine (SMC) and S-methyl-l-cysteine sulfoxide (SMCSO), in human body fluids using isotope-labelled internal standards and liquid chromatography-mass spectrometry (LC-MS)/MS techniques. This method was validated according to the guideline of the Royal Society of Chemistry Analytical Methods Committee. It offers significant advantages including simple and fast preparation of human biological samples. The limits of detection of SMC were 0.08 µM for urine and 0.04 µM for plasma. The limits of detection of SMCSO were 0.03 µM for urine and 0.02 µM for plasma. The calibration curves of all matrices showed linearity with correlation coefficients r2 > 0.9987. The intra and inter day precisions in three levels of known concentrations were >10% and >20%, respectively. The quantification accuracy was 98.28 ± 5.66%. The proposed method would be beneficial for the rapid and accurate determination of the SMC and SMCSO in human plasma and urine samples using by isotope labelled internal standards.