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Preparation of flexible rubber composites with high contents of tungsten powders for gamma radiation shielding

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Rare Metals 2022年第7期41卷 2243-2248页

作者： Xiang-Rong xu Jun-Qing Wu jian xu Feng Liu An Xie Jun-liang Liu Ming Zhang School of Chemistry and Chemical Engineering Yangzhou UniversityYangzhou 225002China Environmental Engineering Center China Nuclear Power Research Institute Co.LtdShenzhen 518034China

To prepare tungsten/rubber composites with good gamma-ray shielding performances and fine mechanical properties,a composite surface modifier is employed to make surface modification of the tungsten powders.

关键词： composites composite rubber

Electrochemical oxidation behavior of hydroxypivalaldehyde in the ionic liquids

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Chinese Chemical Letters 2008年第3期19卷 319-323页

作者： jian Fang Zhong De liang He Zhou Zhou Yi Bin xu State Key Laboratory of Chemo/Biosensing and Chemometrics College of Chemistry and Chemical Engineering Hunan University Changsha 410082 China

The similar electrochemical oxidation behaviors of hydroxypivalaldehyde in ionic liquids （ILs） medium, C4MIMPF6, C4MIMBF4 and CsMIMPF6, are investigated using classic electrochemical methods, respectively. Only the product, hydroxypivalic acid is detected by high performance liquid chromatography （HPLC）. It can be conferred that the electrochemical oxidation of hydroxypivalaldehyde consists of two successive one-electron irreversible reactions at glass carbon （GC） electrode and the possible reaction mechanism in the ILs is proposed firstly. The diffusion coefficients of hydroxypivalaldehyde are obtained according to the electrochemical characteristics of hydroxypivalaldehyde in C4MIMPF6, C4MIMBF4 and CsMIMPF6.

关键词： Hydroxypivalaldehyde ILs Cyclic voltammetry Chronocoulometry

Rapid construction of the unique BCD ring system of tricyclo[6.2.1.0]undecane in the C_(19)-diterpenoid alkaloid aconitine

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Chinese Chemical Letters 2017年第8期28卷 1788-1792页

作者： xue Yang Bin Cheng Hang Cheng liang xu jian-Li Wang Key Laboratory of Drug Targeting Ministry of EducationDepartment of Chemistry of Medicinal Natural ProductsWest China College of PharmacySichuan UniversityChengdu610041China State Key Laboratory of Oral Disease West China School of StomatologySichuan UniversityChengdu610041China

A model study leading to the preparation of the unique tricyclo [6.***.1.0] undecane BCD ring systems of aconitine is described. The synthesis features an unprecedented diastereoselective oxidative dearomatization/dimer... 详细信息

关键词： Aconitine Diterpenoid alkaloid Diels-Alder reaction Cascade reaction Wagner-Meerwein rearrangement

Effects of Additives on Sulfur Transformation,Crystallite Structure and Properties of Coke during Coking of High-sulfur Coal

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Journal of Iron and Steel Research International 2015年第10期22卷 897-904页

作者： Sheng-fu ZHANG liang-ying WEN Kun WANG Chong ZOU jian xu College of Materials Science and Engineering Chongqing University

High-sulfur coal, as an alternative coal source, has a relatively high proportion in coal reserves. However, the feature of high sulfur content, which can cause environmental pollution and poor quality of molten iron, restrains its utilization in coking industry. Coking experiments of high-sulfur coal with Fe2O3, La2O3 and CaO as additives were carried out in order to fix the sulfur in coke. The effects of additives on sulfur distribution, crystallite structure, surface morphology and properties of coke were investigated. The results indicate that CaO can be used as sulfur-fixing agent in coking process, and CaS is the main mineralogical phase of the sulfur-contained mineral constituents in coke. Fe2O3 and La2O3 facilitate the conversion of CaO to CaS. The additives mainly influence the crystallite height and the average interlayer spacing doo2 of coke. The addition of La2O3 increases the value of the crystallite height while the addition of CaO and Fe2O3 decreases it. CaO leads the pores of coke to increase with its physical action and agglomerating characteristic. Fe2O3 and C can form （Fe,C）, resulting in the pulverization and erosion of the pore wall. La2O3 makes the coke surface become more compact and thinner. The reactivity of coke increases with the decrease of crystallite height and crystallite layer number.

关键词： coke additive sulfur transformation crystallite structure coke reactivity coke strength after reaction

Using modified Soil Conservation Service curve number method to simulate the role of forest in flood control in the upper reach of the Tingjiang River in China

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Journal of Mountain Science 2017年第1期14卷 1-14页

作者： LIN Wei YANG Fan ZHOU liang xu jian-gang ZHANG Xing-qi School of Geographic and Oceanographic Sciences Nanjing University Nanjing 210023 China Faculty of Geomatics Lanzhou Jiaotong University Lanzhou 730070 China Institute of Geographic Sciences and Natural Resources Research CAS Beijing 100101 China School of Architecture and Urban Planning Nanjing University Nanjing 210093 China

To improve flood control efficiency and increase urban resilience to flooding,the impacts of forest type change on flood control in the upper reach of the Tingjiang River(URTR) were evaluated by a modified model based on the Soil Conservation Service curve number(SCS-CN) method. Parameters of the model were selected and determined according to the comprehensive analysis of model evaluation indexes. The first simulation of forest reconstruction scenario,namely a coniferous forest covering 59.35km^2 is replaced by a broad-leaved forest showed no significant impact on the flood reduction in the URTR. The second simulation was added with 61.75km^2 bamboo forest replaced by broad-leaved forest,the reduction of flood peak discharge and flood volume could be improved significantly. Specifically,flood peak discharge of 10-year return period event was reduced to 7-year event,and the reduction rate of small flood was 21%-28%. Moreover,the flood volume was reduced by 9%-14% and 18%-35% for moderate floods and small floods,respectively. The resultssuggest that the bamboo forest reconstruction is an effective control solution for small to moderate flood in the URTR,the effect of forest conversion on flood volume is increasingly reduced as the rainfall amount increases to more extreme magnitude. Using a hydrological model with scenarios analysis is an effective simulation approach in investigating the relationship between forest type change and flood control. This method would provide reliable support for flood control and disaster mitigation in mountainous cities.

关键词： Flood control Soil Conservation Service curve number method Forest type change Scenarios simulation Tingjiang River

Hydrothermal Treatment of Polyamide 6 with Presence of Lanthanum Chloride

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Chinese Journal of Polymer Science 2016年第4期34卷 399-406页

作者： Zhi-liang Wang Jia-li xu Qian Yuan Mahmoud H.M.A.Shibraen jian xu 杨曙光 State Key Laboratory for Modification of Chemical Fibers and Polymer Materials College of Material Science and EngineeringDonghua UniversityShanghai 201620China Lab of Polymer Physics and Chemistry Institute of ChemistryChinese Academy of SciencesBeijing 100190China

Hydrothermal processing of polyamide 6 （PA6） with the presence of lanthanum chloride （LaC13） was studied in the temperature region from 160 to 250℃. PA6 will be dissolved in the superheated water when temperature is above 160℃. And as PA6 is dissolved, hydrolysis will happen, which makes PA6 chains degrade. By adding LaCl3 in the hydrothermal environment, the PA6 hydrolysis will intensify, especially when the hydrothermal temperature is higher than 200℃. When the hydrothermal system cools down, the hydrolyzed PA6 segments will crystallize from the solution or remain dissolved in the solution depending on molecular weight. In addition, the hydrolyzed compound of LaCl3 would affect the crystallization of PA6 segments with proper size, and yphase would be presented.

关键词： Nylon 6 Hydrolysis Hydrothermal processing Crystallization.

Reductivity and bundle shifts

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Applied Mathematics(A Journal of Chinese Universities) 2019年第1期34卷 27-32页

作者： xu An-jian College of Science Chongqing University of Technology

For the Hardy space H_E^2(R) over a ?at unitary vector bundle E on a ?nitely connected domain R, let TE be the bundle shift as [3]. If B is a reductive algebra containing every operator ψ(TE) for any rational functi... 详细信息

关键词： reductivity bundle shift multiply-connected domain

Reducing LncRNA-5657 expression inhibits the brain inflammatory reaction in septic rats

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Neural Regeneration Research 2021年第7期16卷 1288-1293页

作者： Yi-An Zhan Xin-liang Qiu xu-Zhen Wang Ning Zhao Ke-jian Qian Department of Critical Care Medicine the First Affiliated Hospital of Nanchang UniversityNanchangJiangxi ProvinceChina Department of Critical Care Medicine Xingguo County People’s HospitalGanzhouJiangxi ProvinceChina

Our preliminary study found that the long noncoding RNA(LncRNA)-5657 can reduce the expression of inflammatory factors during inflammatory reactions in rat glial ***, the role played by LncRNA-5657 during septic brain injury remains *** the present study, rat models of septic encephalopathy were established by cecal ligation and puncture, and then the rats were treated with a hippocampal injection small hairpin RNA(sh RNA) against LncRNA-5657(sh-LnCRNA-5657).The sh-LncRNA-5657 treatment reduced the level of neuronal degeneration and necrosis in the rat hippocampus, reduced the immunoreactivities of aquaporin 4, heparanase, and metallopeptidase-9, and lowered the level of tumor necrosis *** cells were pre-treated with sh-LncRNA-5657 and then treated with 1 μg/mL ***-LncRNA-5657 transfection decreased the expression of LncRNA-5657 in lipopolysaccharide-treated glial cells and decreased the mRNA and protein levels of tumor necrosis factor-alpha, interleukin-1β, and *** findings suggested that LncRNA-5657 expression can significantly reduce the inflammatory reaction during septic encephalopathy and induce protective effects against this *** study was approved by the Institutional Ethics Committee at the First Affiliated Hospital of Nanchang University of China(approval No.2017-004) in 2017.

关键词： brain injury glial cells inflammation injury lipopolysaccharide long noncoding RNA repair sepsis

Isolation and characterization of a high-efficiency marine diesel oil-degrading bacterium

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Petroleum Science 2021年第2期18卷 641-653页

作者： Jin Gao Jie Ming Meng xu Xinge Fu liang-Feng Duan Cong-Chao xu Yu Gao jian-liang xue Xin-Feng Xiao College of Safety and Environmental Engineering Shandong University of Science and TechnologyQingdao266590China College of Chemical Engineering China University of PetroleumBeijing102249China

In the recent 50 years,marine oil spills had resulted in severe environmental pollution problems *** this study,12 petroleum-degrading strains named MJ1 to MJ12,which can use diesel oil as the sole carbon source for growth,were isolated from the seawater in Jiaozhou Bay,*** MJ4 has the highest diesel-degrading rate which is up to 26.54%in 5 days with the diesel oil concentration of 10 g/*** to the BLAST research,16SrRNA sequence of MJ4 showed 99%similarity to Bacillus megaterium ***-factor experiments and response surface methodology were carried out to optimize the environmental factors and their reciprocal action for affecting the diesel oil degradation process of Bacillus *** of single-factor experiments revealed that the highest degradation rate was obtained with temperature of 28°C,pH of 8.8,diesel oil concentration of 25 g/L,P/N ratio of 0.56,nitrogen and phosphorus dosage quantity of 0.35 g/L and 0.18 g/L,respectively.A nonlinear regression equation of diesel oil degradation rate and pH,temperature,P/N ratio was *** model predicted the maximum degradation rate of 72.21%with temperature of 28°C,pH of 8.88,P/N ratio of 0.31,respectively.

关键词： Bioremediation Bacillus megaterium MJ4 Environmental factors Marine oil spill Response surface methodology