Different Concentrations Of Sulfur Research Articles

Growth, Yield and Quality of Garilic (Allium sativum L.) Influenced by the Application of Sulphur and Salicylic Acid

A research experiment was conducted at vegetable research Complex, Maharajpur, Department of Horticulture, College of Agriculture, JNKVV Jabalpur. The experiment was done to study the effect of sulphur and salicylic acid on Yamuna safed -2 variety of Garlic. The growth, yield, and quality of garlic can be influenced by various factors, including nutrient availability and plant growth regulators like salicylic acid. Sulphur is an essential nutrient for plant growth and plays a crucial role in the development of garlic plants. The experiment was conducted in Randomized Block Design with combination of different concentrations of sulphur (0 kg/ha, 30 kg/ha and 45 Kg/ha) and salicylic acid (60 ppm and 120 ppm). Growth parameters like plant height, number of leaves and pseudostem diameter were found maximum in treatment T-9 (sulphur 45kg/ha and SA 120ppm). Yield parameters like average bulb weight (22.27 gm), Polar diameter (4.41 cm) and Equatorial diameter (3.79 cm) average weight of 10 cloves (9.10 gm), Total soluble solids and Pyruvic acid were also maximum in T-9 (Sulphur 45kg/ha and SA 120 ppm) (42.30 oBrix and 66.09 µmol/gm respectively). From the above findings it can be concluded that for garlic plant the best doses for salicylic acid and sulphur were found to be 120 ppm and 45 kg/ha. Also with graded levels of salicylic acid and sulphur various parameters increased effecttively.

DFT Model of Elemental Sulfur in Sulfolane Solutions.

The structure and the thermodynamic and optical (UV) properties of elemental sulfur solution in sulfolane (Sl) have been studied using density functional theory methods. The cyclic molecular form of sulfur (S8 "crown") was found using PBE1PBE/6-311+G(d,p) approximation in combination with a polarizable continuum model (the integral equation formalism variant) to exist in sulfolane medium as a Sl-S8-Sl solvate. It has been theoretically established that sulfur can form stable (S8)n clusters in concentrated solutions. An increase in the extent of association (n) of the sulfur cluster leads to a decrease in the extinction coefficient [TD-DFT(TPSSTPSS/6-311+G(d,p))] of the most intense absorption maximum lying at about 50,000 cm-1 while maintaining the shape of the remaining part of the spectrum. The observed pattern qualitatively expresses the spectral regularities of solutions with different concentrations of sulfur in sulfolane. It has been proposed that a model of the absorption spectrum of elemental sulfur suggests a minor contribution of the S12 molecular form (G298°((S12)2) - G298°((S8)3) ≈ -15.5 kJ mol-1). The findings of the study will provide deeper insights into the transformation of molecular forms of sulfur and more precisely analyze processes involving sulfur as an acting species using electronic spectroscopy.

Simulation of ionic-liquid extractive purification process of thiophene and m-xylene from their mixture with n-hexane by the molecular dynamics method

This paper deals with the results of simulation of extractive purification process of model diesel fuel (the mixture of n-hexane with thiophene and m-xylene) by molecular dynamics simulation using N-methylpyrrolidinium acetate ionic liquid as an extractant. The extractive purification process was simulated for several model fuel systems with different concentrations of sulfur and aromatic containing components. The ionic liquid exhibits high extractive ability, the degrees of desulfurization and dearomatization reach 85–90 and 60[Formula: see text]wt.%, respectively. The results were proved by experimental studies of a mixture by the ionic liquid. After 1[Formula: see text]h of contact of the ionic liquid and the model mixture, the degree of purification against thiophene was 94.2[Formula: see text]wt.%.

Network formation of low molecular weight ‘liquid’ polymers studied by gel permeation chromatography and stress-strain analysis according to Mooney-Rivlin

The rheological and mechanical properties of elastomers are defined by their different networks: The crosslink network and the filler network. The crosslink network is influenced by the polymer structure. The filler network – particularly in case of silica as filler – depends on the interaction between the filler particles and the polymer. Liquid polymers can affect these networks by their lower molecular weight and with certain types by their functional groups. The goal of the present work is to gain a better understanding of the network formation: 1. During the sulfur curing of pure liquid polybutadienes with different concentrations of sulfur and curatives, and 2. Through differently added liquid polymer-silica-masterbatches in sulfur cured silica/SSBR mixtures. For the first point, the pre-cured liquid polymer samples were analyzed by gel permeation chromatography. The results indicate an association between weight concentration and the polymer chain length. For the second point, stress-strain analysis according to Mooney-Rivlin provides information about the interaction of liquid polymers with silica and the main polymer when it is added differently throughout the masterbatch approach.

Enhanced visible-light photovoltaic and photocatalytic performances of SnSe1-xSx nanostructures

In this paper, the pristine SnSe and SnSe1 − xSx nanostructures with different concentrations of sulfur were synthesized by a simple, fast, environmentally-friendly, and inexpensive co-precipitation method. Then, the effect of sulfur concentration on the photovoltaic and photocatalytic properties of the nanostructures was investigated. The results show that in presence of sulfur and its concentration change, the crystallite size and the strain of nanostructures change. Also, among nanostructures, S(6%)-doped SnSe nanostructure indicates the significant photocatalytic activity in the degradation of organic dyes and the significant photovoltaic response under visible light. These results can be due to the reducing crystal defects, the reducing electron-hole recombination, and the improving textural characteristics, which lead to reducing the agglomeration of nanostructures and thus increase the absorption of optical photons and more production of electron-hole pairs. Also, the study of photovoltaic properties shows that the highest photocurrent density and lowest diode coefficient belong to S(6%)-doped SnSe nanostructure.

Synergistic effect of sulfur-doped reduced graphene oxide created via microwave-assisted synthesis for supercapacitor applications

Doping heteroatoms is an effective means of modifying the electrochemical properties of reduced graphene oxide (rGO). In this work, we propose the modification of rGO via microwave-assisted synthesis with different concentrations of sulfur at 140 °C for 30 min. Characterization using X-ray diffraction, Fourier-transform infrared, and Raman spectroscopy revealed successful doping with sulfur to alter the physical properties of rGO. The morphology of doped S-rGO samples exhibited wrinkling and folding of graphene sheets. Electrochemical evaluation revealed S-rGO with 0.25 M of sulfur (S-rGO-0.25) to have excellent electrochemical performance, with a specific capacitance of 237.6 F g−1 compared to the S-rGO with 0.15 M (S-rGO-0.15) and S-rGO with 0.50 M (S-rGO-0.50) with 98.2 and 61.7 F g−1 respectively. Furthermore, S-rGO-0.25 was validated as having an outstanding capacitance retention of 106% after 10,000 cycles signifying that it has promising potential as an electrode material for supercapacitor applications.

РЕШЕНИЕ ЗАДАЧИ МНОГОКРИТЕРИАЛЬНОГО ВЫБОРА ВАРИАНТА РЕКОНСТРУКЦИИ УСТАНОВОК ГИДРООЧИСТКИ ДИЗЕЛЬНОГО ТОПЛИВА

The article describes a diesel fraction hydrofining plant as a rather complex object of management where an important criterion is the optimal resource management of the processes of technological units. This implies maintaining the optimal mode for regulation of the main parameters of the plants, which determine the output product quality. Under inadequate temperature and pressure values, as well as other insufficient operating parameters, the sulfur content in the raw material increases and the cost of the output product decreases. There are several types of hydrofining plants on the Russian market, each of them shows high operating efficiency under different modes. An iterative-fragmentary approach for developing a model of multifactor preferences for selecting the efficient hydrofining plants with optimal modes has been proposed. The results of hydrofining plants processing the different concentrations of sulfur in the raw material and different amounts of the raw material per year were taken as the initial data. Testing of the plants chosen for the study was carried out under different power loads for the raw materials, volumetric feed rates, tempera-ture and hydrogen-containing gas circulation. The optimal choice of the hydrofining plant model and its operating parameters guarantees the high quality of diesel fuel.

Relation between activation energy and induction in rubber sulfur vulcanization: An experimental study

AbstractThe article presents the possibility to use the so‐called frequency factors in order to select the optimal temperature to mix rubber blend recipes before vulcanization without inducing premature crosslinking. As secondary result of the research, it provides a very simple approach to evaluate induction assuming a first order kinetic approach. It has been frequently observed that the activation energy in a first order rubber vulcanization scheme appears to be function of the particular activators used and that activation energy links to the so‐called waiting time (and induction) by means of the frequency factor through an exponential relationship. A total of 212 rheometer curves are experimentally obtained and suitably postprocessed, consisting of pure natural rubber (NR), polybutadiene (PB), and 50–50 or 70%–30% NR‐PR blends in presence of different concentrations of sulfur and accelerants (diphenyl guanidine [DPG] and N‐t‐butylbenzothiazole‐sulfenamide [TBBS]). Data reduction is carried out to have an insight into the most suitable temperature to utilize in the different cases in order to: (a) Obtain the best mixed blends without risking premature vulcanization and (b) design the induction phase without over vulcanize the blend and/or delaying curing because the time required is too long. Waiting time and induction are evaluated by means of a well‐established exponential law requiring the knowledge of the activation energy (assuming for the sake of simplicity that crosslinking occurs following a first order reaction kinetic law) and a constant called “frequency factor”. Frequency factor, considering all reactions monomolecular for the sake of simplicity, is assumed of the order of magnitude of 10−13–10−14 s. All experimental data carried out are critically compared and a wide explanation of the expected induction times and most suitable temperatures to use in the mixing phase is provided in the different cases considered. The article provides a meaningful insight into the importance of the link existing among activation energy, vulcanization recipe (with particular regard to concentration of accelerants, blend between two rubbers with very different activation energies and interaction between two accelerants) and mixing temperature to adopt before curing.

Synthesis and characterization of radio and thermoluminescence properties of Sm doped Gd2O3, Gd2O2S and Gd2O2SO4 nanocrystalline phosphors

In this study, nanocrystalline Gd2O3:Sm, Gd2O2S:Sm and Gd2O2SO4:Sm phosphors were successfully synthesized through the urea homogeneous precipitation method. Nanocrystalline Gd2O2S:Sm phosphors with two different concentrations of sulfur were prepared. In the first procedure, the weight of sulfur was five times more than Gd2O3 weight (was called sample Gd2O2S:Sm(1)) and in the second procedure, it was equal (was called sample Gd2O2S:Sm(2)). The nanocrystalline powders were characterized by X-ray diffraction, Fourier transform infrared spectroscopy, scanning electron microscopy, energy-dispersive X-ray spectroscopy, radioluminescence and thermoluminescence. The XRD and FT-IR results confirmed that nanocrystalline Gd2O3:Sm, Gd2O2S:Sm and Gd2O2SO4:Sm powders had the cubic, hexagonal and orthorhombic structure in preparation temperatures of 620 °C and 900 °C. The SEM images showed that nanocrystalline Gd2O3:Sm, Gd2O2S:Sm and Gd2O2SO4:Sm powders had a semi-spherical shape with a uniform mean size of about 30 nm in diameter and confirmed the XRD results. The presence of all elements was confirmed in the synthesized samples using EDX spectroscopy. The results showed that the weight percent of sulfur during the preparation of Gd2O2S had an effect on the size, morphology and the luminescence intensity of nanocrystalline Gd2O2S powder. Under X-ray irradiation (40 kV and 40 mA), the emission spectra of nanocrystalline Gd2O3:Sm, Gd2O2S:Sm and Gd2O2SO4:Sm phosphors were studied. The results showed the orange-red emission peaks which were observed at 605 nm were the strongest emission peak for all nanocrystalline Gd2O3:Sm, Gd2O2S:Sm and Gd2O2SO4:Sm powders. This peak was corresponded to the 4G5/2-7H7/2 energy transition of Sm3+ ion. The TL response of Gd2O3:Sm, Gd2O2S:Sm and Gd2O2SO4:Sm after irradiation with different X-ray time exposure exhibited a peak shifting towards the lower temperatures. The glow curve deconvolution method was used to calculate trapping parameters and the obtained results were investigated in detail.

Nutritional optimization of Arthrospira platensis for starch and Total carbohydrates production.

Present study aims to optimize the production of starch and total carbohydrates from Arthrospira platensis. Growing concerns toward unprecedented environmental issues associated with plastic pollution has created a tremendous impetus to develop new biomaterials for the production of bioplastic. Starch-based biopolymers from algae serve as sustainable feedstock for thermoplastic starch production due to their abundant availability and low cost. A. platensis was cultivated in Zarrouk's medium at 32 ± 1°C and exposed to red light with a photoperiod of 12:12 hr light/dark. Growth kinetics studies showed that the maximum specific growth rate (μmax ) obtained was 0.059 day-1 with the doubling time (td ) of 11.748 days. Subsequently, Zarrouk's medium with different concentrations of sulfur, phosphorus and nitrogen was prepared to establish the nutrient-limiting conditions to enhance the accumulation of starch and total carbohydrates. In this study, the highest starch accumulated was 6.406 ± 0.622 mg L-1 under optimized phosphorus limitation (0.025 g L-1 ) conditions. Nitrogen limitation (0.250 g L-1 ) results demonstrated significant influenced (p < 0.05) on total carbohydrates (67.573 ± 2.893 mg L-1 ) accumulation in A. platensis. The starch accumulation in A. platensis was significantly affected (p < 0.05) by phosphorus limitation (0.0025 g L-1 ). Subsequently, the optimized phosphorus concentration was coupled with mixotrophic cultivation to further enhance the starch accumulation. The results obtained indicated that, the starch (11.426 ± 0.314 mg L-1 ) and carbohydrates (43.053 ± 2.986 mg L-1 ) concentration obtained was significantly high (p < 0.05) under mixotrophic cultivation. Therefore, it shown that nutrient limitation and mixotrophic cultivation are viable strategies to enhance the accumulation of starch and total carbohydrates in A. platensis.

External-forcing modulation on temporal variations of hydrothermalism-evidence from sediment cores in a submarine venting field off northeastern Taiwan.

The temporal variation of sulfur and metals in core sediments off Kueishantao Islet, a hydrothermal vent site at northeastern Taiwan, was explored to elucidate the changes in submarine hydrothermal emanation over a centennial time scale. The discharge of acidic fluids containing abundant sulfides and dissolved metals results in different concentrations of sulfur and metal accumulating in deposited sediments. In addition to particle size and organic carbon affecting metal contents, the content of total sulfur (TS), which is regarded as an indicator of hydrothermalism, correlates positively and strongly with Fe and other metals; however, it correlates negatively with another index of hydrothermalism, the Al/(Al+Fe+Mn) ratio. The TS content in Core Ks2, the core closest to the vents, increased during 1950–1956, 1968–1970, 1982–1987, 1990–1992, and 2004–2005, but decreased during 1967–1968, 1988–1990, and 1994–1995. The chronological changes in the TS concentration of Cores Ks3 and S2 were very similar to those of Core Ks2 within the aforementioned time spans. The numerous large earthquakes (ML > 5) and typhoons that affect northeastern Taiwan appear to influence hydrothermal emanation and determine the temporal variation of sulfur and metals in sediment cores.

The use of principal component analysis for the assessment of the spatial variability of curative waters from the Busko-Zdrój and Solec-Zdrój region (Poland) – preliminary results

Abstract In the Busko-Zdrój and Solec-Zdrój region (Poland), curative waters with different concentrations of sulphur(II) compounds are extracted. In this paper, waters from 14 intakes were considered. The waters analysed are chloride-sodium, sulphide, iodide (Cl–Na, S, I) or chloride-sodium, sulphide (Cl–Na, S) and are especially associated with deep circulation systems (Jurassic limestones) or shallow circulation systems mostly connected with Cretaceous formations (Senonian marls and limestones and Cenomanian sands and sandstones). The aim of this research is to evaluate the similarities or differences between samples of curative water taken from different geological formations and locations. Principal component analysis was used to assess the similarities between samples of curative waters collected from the intakes being examined. Two principal components were extracted. The analysis indicated that there is a difference between the chemical composition of waters taken from different stratigraphies. Water samples from Cretaceous formations of Cenomanian and Senonian age are similar. There is a small difference observed for waters abstracted from the Neogene and Cretaceous. However, these differences mostly resulted from SO42− and Ca2+ concentrations.

Matrix effects of calcium on high-precision sulfur isotope measurement by multiple-collector inductively coupled plasma mass spectrometry

Multiple-collector inductively coupled plasma mass spectrometry (MC-ICP-MS) has been successfully applied in the rapid and high-precision measurement for sulfur isotope ratios in recent years. During the measurement, the presence of matrix elements would affect the instrumental mass bias for sulfur and these matrix-induced effects have aroused a lot of researchers’ interest. However, these studies have placed more weight on highlighting the necessity for their proposed correction protocols (e.g., chemical purification and matrix-matching) while less attention on the key property of the matrix element gives rise to the matrix effects. In this study, four groups of sulfate solutions, which have different concentrations of sulfur (0.05–0.60mM) but a constant sequence of atomic calcium/sulfur ratios (0.1–50), are investigated under wet (solution) and dry (desolvation) plasma conditions to make a detailed evaluation on the matrix effects from calcium on sulfur isotope measurement. Based on a series of comparative analyses, we indicated that, the matrix effects of calcium on both measured sulfur isotope ratios and detected 32S signal intensities are dependent mainly on the absolute calcium concentration rather than its relative concentration ratio to sulfur (i.e., atomic calcium/sulfur ratio). Also, for the same group of samples, the matrix effects of calcium under dry plasma condition are much more significant than that of wet plasma. This research affords the opportunity to realize direct and relatively precise sulfur isotope measurement for evaporite gypsum, and further provides some suggestions with regard to sulfur isotope analytical protocols for sedimentary pore water.

A closed form solution for the vulcanization prediction of NR cured with sulphur and different accelerators

The paper presents a novel efficient closed form approach to determine the degree of vulcanization of natural rubber (NR) vulcanized with sulphur in presence of different accelerators. The general reaction scheme proposed by Han and co-workers for vulcanized sulphur NR is re-adapted and suitably modified taking into account the single contributions of the different accelerators, focusing in particular on some experimental data, where NR was vulcanized at different temperatures (from 150 to \(180\, ^{\circ }\hbox {C}\)) and concentrations of sulphur, using TBBS and DPG in the mixture as co-agents at variable concentrations. In the model, chain reactions initiated by the formation of macro-compounds responsible for the formation of the unmatured crosslinked polymer are accounted for. It is assumed that such reactions depend on the reciprocal concentrations of all components and their chemical nature. In presence of two accelerators, reactions are assumed to proceed in parallel, making the assumption that there is no interaction between the two accelerators. Despite there is experimental evidence that a weak process by which each accelerator affects the other, the reaction chemistry is still not well understood and therefore its effect cannot be translated into any mathematical model. In any case, even disregarding such interaction, good approximations of the rheometer curves are obtained. From the simplified kinetic scheme adopted, a closed form solution is found for the crosslink density, with the only limitation that the induction period is excluded from computations. The main capability of the model stands however in the closed form determination of kinetic constants representing the velocities of single reactions in the kinetic scheme adopted, which allows avoiding a numerically demanding least-squares best fitting on rheometer experimental data. Two series of experiments available, relying into rheometer curves at different temperatures and different concentrations of sulphur and accelerators, are utilized to evaluate the fitting capabilities of the mathematical model. Very good agreement between numerical output and experimental data is experienced in all cases analyzed.

Cadmium accumulation, sub-cellular distribution and chemical forms in rice seedling in the presence of sulfur

Changes in cadmium (Cd) accumulation, distribution, and chemical form in rice seedling in the joint presence of different concentrations of sulfur (S) remain almost unknown. Therefore, the indoor experiments were performed to determine the accumulation, sub-cellular distribution and chemical forms of Cd under three S levels in rice seedling for the first time. The result showed that Cd accumulation in rice roots was more than in shoots. Sub-cellular distribution of Cd in rice roots and shoots indicated that the largest proportion of Cd accumulated in cell walls and soluble fractions. As S supply increased, the proportion of Cd in cell walls reduced, while it increased in the soluble fractions. The majority of Cd existed in inorganic form, and then gradually changed to organic forms that included pectates and proteins with increased S supply. The results showed that S supply significantly influenced Cd accumulation, distribution, and chemical forms, suggesting that S might provide the material for the synthesis of sulfhydryl protein and thereby affect Cd stress on plants. These observations provided a basic understanding of potential ecotoxicological effects of joint Cd and S exposure in the environment.

Hibiscus chlorotic ringspot virus Coat Protein Upregulates Sulfur Metabolism Genes for Enhanced Pathogen Defense

In both Hibiscus chlorotic ringspot virus (HCRSV)-infected and HCRSV coat protein (CP) agroinfiltrated plant leaves, we showed that sulfur metabolism pathway related genes-namely, sulfite oxidase (SO), sulfite reductase, and adenosine 5'-phosphosulfate kinase-were upregulated. It led us to examine a plausible relationship between sulfur-enhanced resistance (SED) and HCRSV infection. We broadened an established method to include different concentrations of sulfur (0S, 1S, 2S, and 3S) to correlate them to symptom development of HCRSV-infected plants. We treated plants with glutathione and its inhibitor to verify the SED effect. Disease resistance was induced through elevated glutathione contents during HCRSV infection. The upregulation of SO was related to suppression of symptom development induced by sulfur treatment. In this study, we established that HCRSV-CP interacts with SO which, in turn, triggers SED and leads to enhanced plant resistance. Thus, we have discovered a new function of SO in the SED pathway. This is the first report to demonstrate that the interaction of a viral protein and host protein trigger SED in plants. It will be interesting if such interaction applies generally to other host-pathogen interactions that will lead to enhanced pathogen defense.

An experimental and theoretical study of gas tungsten arc welding of stainless steel plates with different sulfur concentrations

During fusion welding, the presence of sulfur in steel often affects heat and fluid flow in the weld pool and its geometry. While the role of sulfur during welding of stainless steel plates with the same sulfur content is well understood, welding of stainless steel plates containing different concentrations of sulfur has not yet received proper attention. Here we report an experimental and modeling investigation of gas tungsten arc butt welding of stainless steel plates containing different sulfur concentrations. The main variables studied were sulfur concentrations in the two plates, welding current and welding speed. The results show significant shift of the fusion zone toward the low sulfur steel. The asymmetric fusion zone profile with respect to the original joint interface could be quantitatively explained through numerical modeling of heat transfer and fluid flow considering a bead shift observed experimentally.

Synthesis and optical properties of partially S-doped ZnO symmetric three-sidedfeather-like nanostructures

Partially S-doped ZnO symmetric three-sided feather-like nanostructures havebeen synthesized via a thermal evaporation and transport method. The productswere grown in a one-step catalyst-free process. The synthesized nanostructures ofboth samples have nearly the same morphology although these contain differentconcentrations of sulfur (1.55 and 10.48 at.%). Our study suggests that the stemswere S-doped while the teeth were not. These synthesized nanostructures weresingle-crystalline wurtzite structures. Room temperature photoluminescence (PL)spectra of the synthesized products showed three PL peaks in the ultraviolet,blue and green emission regions. The peaks were shifted towards high energyby sulfur doping. These symmetric three-sided nanostructures may be used inthree-dimensional nanolasers in optoelectronics and nanorotors in nanomechanical systems.

Thermal Stability Study of S-Se Amorphous Compounds

Amorphous selenium containing different concentrations of sulphur (0-5 at.%) has been prepared by quenching the melt in air. The compositional dependence of density, hardness, specific heat, glass forming tendency as well as crystallization enthalpy have been measured, and the correlation between the obtained data and the chemical binding has been discussed. A cyclic scanning technique has been used to investigate the thermally induced phase during two consecutive heating-cooling cycles covering the temperature range Tg-Tm. The activation energy of crystallization using non-isothermal technique (DSC) has been determined and discussed.

Photosynthesis, chlorophyll fluorescence, and water relations in young sugar beet plants as affected by sulfur supply

The effect of different concentrations of sulfur (1 and 3 mM) and interruption of sulfur (S) supply for 25 days on the photosynthesis and leaf water relations in young sugar beet plants (Beta vulgaris L.) was studied in water culture, under greenhouse conditions. Interruption of S‐supply significantly reduced the content of sulfur, chlorophylls a+b and carotenoids, leaf area, density of stomatal and epidermal cells, transpiration rate and leaf water potential, while it increased the free proline content and stomatal diffusion resistance. An increase in S concentration in the nutrient medium from 1 to 3 mM did not significantly affect the tested parameters, except for an increase in leaf S content and a decrease of leaf water potential. Sulfur deficiency caused a pronounced decrease of the rate and quantum yield of photosynthetic oxygen evolution under non‐photorespiratory conditions. This was partly the result of the diminished photochemical efficiency of photosystem II reaction centers. Less efficient excitation of PSII reaction centers is most probably the consequence of higher thermal energy dissipation in the reaction centers of S‐starved plants. These data support that S nutrition is one of the factors regulating plant photosynthesis.