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Water Science and Engineering 2023年第2期16卷 143-153页

作者： Maria F.Carboni Sonia Arriaga Piet N.L.Lens National University of Ireland Galway H91 TK33 GalwayIreland Instituto Potosino de Investigación Científica y Tecnológica 78216 San Luis PotosíMexico

In this study, simultaneous nitrification and autotrophic denitrification (SNAD) with either elemental sulfur or pyrite were investigated in fluidized bed reactors in mesophilic conditions. The reactor performance was evaluated at different ammonium (12-40 mg/L of NH4+-N), nitrate (35-45 mg/L of NO3--N), and dissolved oxygen (DO) (0.1-1.5 mg/L) concentrations, with a hydraulic retention time of 12 h. The pyrite reactor supported the SNAD process with a maximum nitrogen removal efficiency of 139.5 mg/(L·d) when the DO concentration was in the range of 0.8-1.5 mg/L. This range, however, limited the denitrification efficiency of the reactor, which decreased from 90.0% ± 5.3% in phases II-V to 67.9% ± 7.2% in phases VI and VII. Sulfate precipitated as iron sulfate (FeSO4/Fe2(SO4)3) and sodium sulfate (Na2SO4) minerals during the experiment. The sulfur reactor did not respond well to nitrification with a low and unstable ammonium removal efficiency, while denitrification occurred with a nitrate removal efficiency of 97.8%. In the pyrite system, the nitrifying bacterium Nitrosomonas sp. was present, and its relative abundance increased from 0.1% to 1.1%, while the autotrophic denitrifying genera Terrimonas, Ferruginibacter, and Denitratimonas dominated the community. Thiobacillus, sulfurovum, and Trichlorobacter were the most abundant genera in the sulfur reactor during the entire experiment.

关键词： Pyrite elemental sulfur Simultaneous nitrification and denitrification Nitrogen removal 16S rRNA

elemental sulfur effects on Pb and Zn uptake by Indian mustard and winter wheat

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Journal of Environmental Sciences 2003年第6期15卷 836-840页

作者： CUI Yan-shan, WANG Qing-ren , DONG Yi-ting, LI Hai-feng (Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China. Research Center for Eco-Environmental Sciences Chinese Academy of Sciences 北京 100085

A pot experiment was conducted to investigate the influence of elemental sulfur to contaminated soil on plant uptake by a heavy metal hyperaccumulator, Indian mustard(Brassica juncea) and a field crop, winter wheat(***). elemental sulfur(S) with different rates was carried out, they were 0(S 0), 20(S 20), 40(S 40), 80(S 80), and 160(S 160) mmol/kg respectively. Extra pots with the same rates of S but without plants were used for soil sampling to monitor pH and CaCl 2-extractable heavy metal changes. The results showed that S enhanced phytoextraction of Pb and Zn from contaminated soil. Application S effectively decreased soil pH down to 1.1 as the most at the rate of S 160. The concentrations of CaCl 2-extractable Pb and Zn in soil and uptake of Pb and Zn by the plants were increased with soil pH decreased. A good correlation between CaCl 2-extractable Pb/Zn and soil pH was found(R 2 Pb = 0.847 and R 2 Zn = 0.991, n=25). With S application, soil CaCl 2-extractable Pb and Zn concentrations, concentration of Pb and Zn in plants and the amount of removal by plant uptake were significantly higher than those without S. Under the treatment of S 160, the highest CaCl 2-extractable Pb and Zn were observed, they were 4.23 mg/kg and 0.40 mg/kg, 2.7 and 2.0 times as that of the control(S 0) respectively. At the highest rates of S(S 160), both Indian mustard and winter wheat reached the highest uptake of Pb and Zn. The highest Pb concentrations in wheat and Indian mustard were 32.8 mg/kg and 537.0 mg/kg, all 1.8 times as that of the control, and the highest Zn concentrations in wheat and Indian mustard were 215.5 mg/kg and 404.0 mg/kg, 2.4 and 2.0 times as that of the control respectively. The highest removals of Pb and Zn from the contaminated soil were 0.41 mg/pot and 0.31 mg/pot by Indian mustard in the treatment of S 160 through 50 days growth.

关键词： elemental sulfur Pb Zn uptake contaminated soil

In-depth study on the solubility of elemental sulfur in sour gas mixtures based on the Chrastil's association model

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Petroleum 2016年第4期2卷 425-434页

作者： Qiao Wang Xiao Guo Runxi Leng State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation Southwest Petroleum UniversityChengduSichuan 610500China Research Institute of Exploration and Development Xinjiang Oilfield CompanyKaramay 834000China

Accurately predicting the solubility of elemental sulfur in sour gas mixtures is a primary *** a current and widely-used model on the solubility of elemental sulfur in sour gas mixtures,Chrastil's association model has a big error in the process of predicting experimental data based on different fitting *** paper combined with experimental data reported by relevant scholars about elemental sulfur solubility in sour gases and selected density,temperature and pressure as three important influential *** to different fitting methods,we can calculate the correlation parameters in Chrastil's *** different solubility formulas can be used to predict the solubility of elemental sulfur in sour gas *** in-depth research and analysis of Chrastil's solubility model from numerical aspects,it's easy to find the irrationality about Chrastil's solubility model and fitting *** in fitting methods,further improvement of the fitting method is proposed and used to predict the solubility of elemental sulfur in sour gas *** calculation results show that some improvements of the predicting precision have been achieved by using the improved fitting method in Chrastil's association model.

关键词： Solubility Numerical analysis elemental sulfur Prediction model Sour gas Chrastil's association model

Synthesis of biheteroaryls via 2-methyl quinoline C(sp^(3))-H functionalization under metal-free conditions

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Green Synthesis and Catalysis 2024年第1期5卷 73-76页

作者： Dahan Wang Yuhan Yang Fuhong Xiao Jinbing Liu Guojiang Mao Guo-Jun Deng Key Laboratory of Environmentally Friendly Chemistry and Application of Ministry of Education Hunan Province Key Laboratory of Green Organic Synthesis and ApplicationCollege of ChemistryXiangtan UniversityXiangtan 411105China Department of Food and Chemical Engineering Shaoyang UniversityShaoyang 422100China School of Chemistry and Chemical Engineering Henan Normal UniversityXinxiang 453007China

An acetic acid-promoted C(sp^(3))-H functionalization of 2-methyl quinoline,enaminoesters and elemental sulfur for the synthesis of 3,4,5-trisubstituted isothiazoles under metal-free conditions has been *** approach provides viable access to various 5-(quinolin-2-yl)isothiazoles in moderate to good yields with good functional group ***,the success of the gram-scale reaction gives this reaction a great potential application.

关键词： C(sp^(3))-H functionalization Multicomponent reactions Biheteroaryls elemental sulfur Metal-free

Multicomponent polymerization of sulfur, chloroform and diamine toward polythiourea

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Science China Chemistry 2023年第3期66卷 870-877页

作者： Nan Zheng He Gao Zihui Jiang Wangze Song Department of Polymer Science and Engineering School of Chemical EngineeringDalian University of TechnologyDalian 116024China

The efficient utilization of elemental sulfur(S8) for developing high value-added chemicals is a global concern considering its abundant sources and yearly accelerating environmental issues. However, it has been a long-standing challenge to directly transform elemental sulfur to sulfur-containing polymer, especially via an environmentally benign manner. Herein, a unique chemo-differentiating multicomponent polymerization(MCP) of elemental sulfur, chloroform, and diamine is reported to construct polythiourea based on amine-involved two sequential reactions including isothiocyanation and nucleophilic *** strategy features isocynide-free monomers as starting materials, mild conditions, high molecular weights(up to72,900 g/mol) and desired yields(up to 83%). With the advantages of inactive isocyanation and active nucleophilic addition, the stoichiometric balance of amine and isothiocyanate could be delicately controlled to afford various polythioureas with high molecular weights. The polythioureas have been further utilized in the Cu-based aqueous catalysis and Hg-based ion adsorption.

关键词： multicomponent polymerization elemental sulfur polythiourea environmental friendliness

Synthesis and Characterization of [(C_5H_4SiMe_2~tBu)_2Ln(μ-S^nBu)]_2 (Ln=Y,Er)

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Chinese Journal of Structural Chemistry 2008年第5期27卷 523-528页

作者：李艳荣张正星陈珍霞刘瑞婷周锡庚 Department of Chemistry Molecular Catalysis and Innovative Material Laboratory Fudan University

（C5H4SiMe2^tBu）2Ln^nBu reacted with 1 equiv, of elemental sulfur in toluene at ambient temperature to yield the corresponding lanthanocene thiolates [（C5H4SiMe2^tBu）2Ln（μ-S^nBu）]2 （Ln = Y （1）, Er （2））. Complexes 1 and 2 have been characterized by elemental analysis, IR, mass spectroscopy and X-ray single-crystal diffraction analysis. Both complexes are of monoclinic with space group P21/c, formula C52H94S2Si4Y2 1 （C52H94S2Si4Er2 2） Mr = 1073.57 （1230.27）, a = 8.495（2）（8.41（2））, b = 26.913（8）（26.67（7））, c = 13.756（4）（13.68（4）） A, α = 90（90）, β = 101.184（5）（101.57（4））, γ = 90 （90）°, V= 3085.1（15）（3007（14）） A^3, Dc = 1.156 （1.359） g·cm^-3, Z= 2 （2）, F（000） = 1144 （1260）, μ = 2.046 （2.951） cm^-1, R = 0.0687 （0.0749） and wR = 0.1306 （0.1507） for observed reflections with I 〉 2σ（I）. X-ray structures of 1 and 2 definitively prove that only one sulfur atom is inserted into the Ln-C（^nBu） bond, forming a thiolate ligand.

关键词： organolanthanide crystal structure insertion elemental sulfur thiolate

Corrosion behavior of low alloy steel for cargo oil tank under upper deck conditions

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Journal of Iron and Steel Research(International) 2018年第1期25卷 120-130页

作者： Hao Li Feng Chai Cai-fu Yang Chao Li Xiao-bing Luo Central Iron and Steel Research Institute Beijing 100081China Qingdao NCS Testing Protection Technology Co. Ltd.Qingdao 266071 Shandong China

A simulated corrosion test apparatus was used to investigate the corrosion behavior of a low alloy steel under simulated upper deck conditions in a cargo oil tank. The estimated corrosion loss of conventional E36 class ship plate steel is 4.27 mm, which is clearly inadequate compared with the standard adopted by International Maritime Organization. Outer rust layer of specimens starts to peel off after 77 days and becomes fragmented after 98 days. X-ray diffraction, scanning electron micros- copy, and Raman spectroscopy revealed that the resulting rust is composed of σ-FeOOH （the main protective phase）, Fe2O3, FeS, elemental S, and FeSO4. FeSO4 in the interface of the base and rust layer leads to localized corrosion. elemental sulfur forms on the surface of σ-FeOOH, and the quantity and size thereof increase with increasing corrosion time. Furthermore, layered elemental sulfur promotes fracture and peels off the rust layer.

关键词： Low alloy steel Cargo oil tank Upper deck Corrosion film elemental sulfur

Research Progress on High Specific Energy Cathode Materials for Rechargeable Lithium sulfur Batteries

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Journal of Rare Earths 2005年第S1期23卷 593-599页

作者：郑伟胡信国张翠芬 Department of Applied Chemistry Harbin Institute of Technology Harbin 150001 China

An overview of the developing survey, research actuality and the future development of high specific energy and power lithium sulfur rechargeable batteries was presented systemically. By introducing the character of sulfur composite material and discussing some promising cathode materials, it may provide some foundation for people to go deep into researching and empoldering the sulfur composite material.

关键词： lithium battery elemental sulfur composite material polysulfide high specific energy

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汽油中元素硫组成变化对其定量分析的影响

分析测试学报 2007年第Z1期26卷 323-326页

作者：赵惠菊中石化九江分公司技术中心江西九江332004

The structure of elemental sulfur (S0) in naphtha and gasoline was studied basing on that a new analytical method for determination of S0 was developed using gas chromatography-mass spectrometry (GC-MS).The test showed that the structure of S0 has changed and a small quantity of S2,S6,S7 has resulted and the mass proportion of S2∶S6∶S7∶S8 was 0.13:0.05:0.04:1.00 under the analysis *** the change of S0 structure with temperature had no effect on its quantity analysis.

关键词： Gas chromatography-mass spectrometry elemental sulfur Naphtha Gasoline Structure

Design and synthesis of unique thiazoloisoquinolinium thiolates and derivatives

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Chinese Chemical Letters 2021年第10期32卷 3211-3214页

作者： Wasim Ahmed Zi-Hao Huang Zi-Ning Cui Ri-Yuan Tang Department of Applied Chemistry College of Materials and EnergySouth China Agricultural UniversityGuangzhou 510642China State Key Laboratory for Conservation and Utilization of Subtropical Agro-Bioresources Integrative Microbiology Research CentreGuangdong Province Key Laboratory of Microbial Signals and Disease ControlSouth China Agricultural UniversityGuangzhou 510642China Guangdong Laboratory for Lingnan Modern Agriculture Guangzhou 510642China

Natural isoquinolinium alkaloids possess a wide range of biological *** design and synthesis of mesoionic isoquinoliniums is of great *** paper reports the synthesis of unique mesoionic thiazoloisoquinolinium thiolates stabilized by aromatization and 1,*** compounds can be synthesized via the three component [2 + 2 + 1] cycloaddition reaction of isoquinolines with ethyl propionate and elemental sulfur in the absence of any metal catalyst and ***,thiazoloisoquinolinium thiolates can be transformed to thioether-containing thiazoloisoquinolinium halides.A selective [4 + 2] cycloaddition can also be used to form S-bridged fused tetracyclic compounds with a thiothiamide ring unit and two quarternary carbon *** I-1 shows good bioactivity against the chlorophyll of duckweed(Lemna minor) with inhibition rate of 51.5 mg/mL.

关键词： Isoquinoline Heterocycle Zewitterionic elemental sulfur Cycloaddition