检索结果-南通市图书馆

Efficient recovery of tungsten from scheelite concentrates using a sulfur-phosphorus mixed acid leaching system

在线全文

学校读者我要写书评

暂无评论

Tungsten 2024年第4期6卷 821-832页

作者： Jiang-Tao Li Li-Li Gao Zhong-wei Zhao xu-heng Liu Xing-Yu Chen School of Metallurgy and Environment Central South UniversityChangsha410083China Key Laboratory of Hunan Province for Metallurgy and Material Processing of Rare Metals Changsha410083China

In recent years,a new process for leaching scheelite concentrates with sulfur-phosphorus mixed acid has been successfully *** process suffers from the elimination of the retarding effect of calcium sulfate,the selective extraction of tungsten from the H_(3)PW_(12)O_(40)-H_(2)SO_(4)-H_(3)PO_(4)mixture solution,and the removal of introduced ***,in this paper,we investigated the inhibition measures of a calcium sulfate-blocking membrane,the selective extraction of tungsten by ion exchange,and the removal of phosphorus by the magnesium ammonium salt *** results showed that the addition of calcium sulfate whisker seeds and a higher H_(3)PO_(4)concentration inhibited spontaneous diffuse nucleation,promoted crystal growth,and avoided the formation of a dense blocking *** 98 wt.%of the scheelite concentrate was digested by H_(2)SO_(4)-H_(3)PO_(4).The selective adsorption of PW_(12)O_(40)^(3-)was realized using D301 resin,and the extraction efficiency of tungsten exceeded 99.9%.After desorption with ammonia water,PW_(12)O_(40)^(3-)was depolymerized into WO_(4)^(2-)and PO_(4)^(3-).99.9 wt.%of phosphorus was removed in the form of MgNH_(4)PO_(4)by the magnesium ammonium salt method,and the residual phosphorus concentration in the solution was lower than 10 mg·L^(-1).After purification,the highest-grade ammonium paratungstate product was prepared by evaporative crystallization.

关键词： Scheelite concentrates Sulfur-phosphorus mixed acid Calcium sulfate Ion exchange Tungsten

Photoinduced radical sulfur dioxide insertion with asymmetric cyclization of alkenes: accessing β-chiral sulfones bearing S-stereocentric cyclic sulfinamides

在线全文

学校读者我要写书评

暂无评论

Science China Chemistry 2025年第1期 257-263页

作者： Jiapian Huang Chenxin Wang xu Wang Xiaoyu Zhou wei Xiao Jie Wu School of Pharmaceutical and Chemical Engineering & Institute for Advanced Studies Taizhou University State Key Laboratory of Organometallic Chemistry Shanghai Institute of Organic Chemistry Chinese Academy of Sciences School of Chemistry and Chemical Engineering Henan Normal University

The generation of various β-chiral sulfones bearing chiral cyclic sulfinamides through photoredox-catalyzed sulfur dioxide insertion with asymmetric radical cyclization is described. This method features a broad substrate scope and excellent stereospecificity. Computational studies reveal that the dispersion interaction between sulfinyl group and CH2SO2Ph group plays a crucial role in the stereoselectivity control.

关键词：

同方期刊数据库

在线全文

学校读者我要写书评

暂无评论

社区同群效应与居民网络消费扩容提质

武汉大学学报（哲学社会科学版） 2025年第1期78卷 146-159页

作者：尹振涛张珩中国社会科学院金融研究所北京100710 中国社会科学院大学应用经济学院北京100710

在百年未有之大变局下,扩内需、促消费已成为推动经济高效循环、满足人民美好生活需要的关键途径。作为人际互动与社会关系构建的关键场所,社区居民所形成的关系网络,不仅能强化居民之间的相互依赖,也能使居民消费行为产生同群效应。社... 详细信息

在百年未有之大变局下,扩内需、促消费已成为推动经济高效循环、满足人民美好生活需要的关键途径。作为人际互动与社会关系构建的关键场所,社区居民所形成的关系网络,不仅能强化居民之间的相互依赖,也能使居民消费行为产生同群效应。社区同群效应的信息传递与知识溢出,在促进居民网络消费扩容提质的同时,可以通过增加网络消费信贷、提升消费等级和降低居民依赖心理,使得低于参考点的居民受到激励,实现网络消费的扩容提质,这一点在男性和银发群体以及处于中小城市和农村地区的居民中表现得更为明显。社区同群效应对居民网络消费所产生的这种积极作用,为建立社区交流机制、设计符合居民需求特点的网络消费信贷体系、树立理性消费观和构建能释放内需动力的消费机制提供了新的实证证据,也丰富了居民消费领域的研究。

关键词：社区同群效应网络消费扩容提质网络消费信贷

The Soft-Strain Effect Enabled High-Performance Flexible Pressure Sensor and Its Application in Monitoring Pulse Waves

同方期刊数据库博看期刊评论

在线全文

学校读者我要写书评

暂无评论

Research 2023年第1期2022卷 525-534页

作者： Yue Li Yuan wei Yabao Yang Lu heng Lei Luo Jiuwei Gao Hanjun Jiang Juncai Song Manzhang xu xuewen Wang wei Huang Frontiers Science Center for Flexible Electronics(FSCFE)and Institute of Flexible Electronics(IFE) Northwestern Polytechnical UniversityXi'an710072China MIIT Key Laboratory of Flexible Electronics(KLoFE) Northwestern Polytechnical UniversityXi'an710072China Shaanxi Key Laboratory of Flexible Electronics(KLoFE) Northwestern Polytechnical UniversityXi'an710072China Key Laboratory of Flexible Electronics of Zhejiang Province Ningbo Institute of Northwestern Polytechnical University218 Qingyi RoadNingbo315103China State Key Laboratory of Organic Electronics and Information Displays Institute of Advanced Materials(IAM)Nanjing University of Posts and TelecommunicationsNanjing210023China Key Laboratory of Flexible Electronics(KLoFE)and Institute of Advanced Materials(IAM) Nanjing Tech University(NanjingTech).Nanjing211800China

Flexible and wearable pressure sensors attached to human skin are effective and convenient in accurate and real-time tracking of various physiological signals for disease diagnosis and health *** flexible pressure sensors are constructed using compressible dielectric or conductive layers,which are electrically sensitive to external mechanical ***,saturated deformation under large compression significantly restrains the detection range and sensitivity of such ***,we report a novel type of flexible pressure sensor to overcome the compression saturation of the sensing layer by softstrain ffect,enabling an utra-high sensitivity of~636 kPa^(-1) and a wide detection range from 0.1 kPa to 56 *** addition,the cyclic loading-unloading test reveals the excellent stability of the sensor,which maintains its signal detection after 10.000 cycles of 10 kPa *** sensor is capable of monitoring arterial pulse waves from both deep tissue and distal parts,such as digital arteries and dorsal pedal arteries,which can be used for blood pressure estimation by pulse transit time at the same artery branch.

关键词： restrain overcome attached

Sterol carrier protein 2: A promising target in the pathogenesis of atherosclerosis

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Genes & Diseases 2023年第2期10卷 457-467页

作者： Can xu heng Li Chao-Ke Tang Institute of Cardiovascular Disease Key Laboratory for Arteriosclerology of Hunan ProvinceHunan Province Cooperative Innovation Center for Molecular Target New Drug StudyThe First Affiliated Hospital of University of South ChinaDepartment of CardiologyHengyang Medical SchoolUniversity of SouthChinaHengyangHunan421001China

Atherosclerosis, the underlying pathophysiological basis of cardiovascular disease, has been recognized as a lipid-driven chronic inflammatory disease. Sterol carrier protein 2 (SCP-2) is a 13-kDa non-specific lipid-transfer protein expressed by various tissues and cells, such as liver, heart, vascular smooth muscle cells (VSMCs), and macrophages. SCP-2 has an extensive role in cardiovascular and metabolic diseases. Recently, SCP-2 was reported to promote the development of atherosclerosis by regulating lipid metabolism and peroxidation, endocannabinoid metabolism, vascular inflammation, and fatty acid metabolism. In this review, we summarized the recent advances regarding the role of SCP-2 in the pathogenesis of atherosclerosis and tried to provide a rationale for future investigation and a better understanding of the biological functions of SCP-2 in atherosclerotic cardiovascular disease.

关键词： Atherosclerosis Fatty acid metabolism Lipid metabolism SCP-2 Vascular inflammation

How do moth and butterfly taste?——Molecular basis of gustatory receptors in Lepidoptera

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Insect Science 2020年第6期27卷 1148-1157页

作者： wei xu Agricultural Sciences College of ScienceHealthEngineering and EducationMurdoch UniversityWAAustralia

Insect gustatory system plays a central role in guiding insect feeding behaviors,insect-plant interactions and *** receptors(GRs)form the interface between the insect taste system and their ***,most studies on insect GRs are focused on Drosophila;much less attention has been paid to Lepidoptera species,which consist of a large number of serious agricultural crop *** the exceptional advances in the next generation sequencing(NGS),cellular biology,RNA interference(RNAi),and clustered regularly interspaced short palindromic repeats(CRISPR)technologies in recent years,extraordinary progresses have been achieved elucidating the molecular mechanisms of Lepidopteran *** this review,we highlighted these advances,discussed what these advances have revealed and provide our new insights into this field.

关键词： bitter receptor CO2 receptor GR43a sugar receptor taste receptor

Expression and Characterization of ArgR, An Arginine Regulatory Protein in Corynebacterium crenatum

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Biomedical and Environmental Sciences 2014年第6期27卷 436-443页

作者： CHEN xue Lan ZHANG Bin TANG Li JIAO Hai Tao xu heng Yi xu Feng xu Hong wei Hua XIONG Yong Hua Key Laboratory of Functional Small Organic Molecule Ministry of Education Jiangxi Normal University State Key Laboratory of Food Science and Technology Nanchang University Ocean NanoTech LLC

Objective Corynebacterium crenatum MT, a mutant from C. crenatum AS 1.542 with a lethal argR gene, exhibits high arginine production. To confirm the effect of ArgR on arginine biosynthesis in C. crenatum, an intact argR gene from wild-type AS 1.542 was introduced into C. crenatum MT, resulting in C. crenatum MT. sp, and the changes of transcriptional levels of the arginine biosynthetic genes and arginine production were compared between the mutant strain and the recombinant strain. Methods Quantitative real-time polymerase chain reaction was employed to analyze the changes of the related genes at the transcriptional level, electrophoretic mobility shift assays were used to determine ArgR binding with the argCJBDF, argGH, and carAB promoter regions, and arginine production was determined with an automated amino acid analyzer. Results Arginine production assays showed a 69.9% reduction in arginine from 9.01±0.22 mg/mL in C. crenatum MT to 2.71±0.13 mg/mL （P〈0.05） in C. crenatum MT. sp. The argC, argB, argD, argF, argJ, argG, and carA genes were down-regulated significantly in C. crenatum MT. sp compared with those in its parental C. crenatum MT strain. The electrophoretic mobility shift assays showed that the promoter regions were directly bound to the ArgR protein. Conclusion The arginine biosynthetic genes in C crenatum are clearly controlled by the regulator ArgR, and intact ArgR in C. crenatum MT results in a significant descrease in production. negative arginine production.

关键词： Corynebacterium crenatum ArgR protein Arginine biosynthetic genes Real-time PCR ElectrophoretJc mobility shift assay

High-entropy(Y0.2Nd0.2Sm0.2Eu0.2Er0.2)AlO3:A promising thermal/environmental barrier material for oxide/oxide composites

在线全文

学校读者我要写书评

暂无评论

Journal of Materials Science & Technology 2020年第12期47卷 45-51页

作者： Zifan Zhao heng Chen Huimin Xiang Fu-Zhi Dai Xiaohui Wang wei xu Kuang Sun Zhijian Peng Yanchun Zhou Science and Technology on Advanced Functional Composite Laboratory Aerospace Research Institute of Materials&Processing TechnologyBeijing100076China School of Engineering and Technology China University of GeosciencesBeijing 100083China Shenyang National Laboratory for Materials Science Institute of Metal ResearchChinese Academy of SciencesShenyang110016China Shanghai Chenhua Science and Technology Corporation Limted Shanghai201804China

Yttrium aluminum perovskite(YAl O3)is a promising candidate material for environmental barrier coatings(EBCs)to protect Al2 O3 f/Al2 O3 ceramic matrix composites(CMCs)from the corrosion of high-temperature water vapor in combustion ***,the relatively high thermal conductivity is a notable drawback of YAl O3 for environmental barrier coating ***,in order to make REAl O3 more thermal insulating,a novel high-entropy rare-earth aluminate ceramic(Y0.2Nd0.2Sm0.2Eu0.2Er0.2)AlO3 was designed and *** as-prepared(Y0.2Nd0.2Sm0.2Eu0.2Er0.2)AlO3 ceramic possesses close thermal expansion coefficient(9.02×10-6/oC measured from room temperature to 1200℃)to that of Al2 *** thermal conductivity of(Y0.2Nd0.2Sm0.2Eu0.2Er0.2)AlO3 at room temperature is 4.1 W·m-1K-1,which is almost one third of the value of YAl ***,to effectively prevent the penetration of water vapor from possible pores/cracks of coating layer,which are often observed in T/EBCs,a tri-layer EBC system REAl O3/RE3 Al5 O12/(Al2 O3 f/Al2 O3 CMCs)is *** thermal expansion coefficient to Al2 O3 and low thermal conductivity of(Y0.2Nd0.2Sm0.2Eu0.2Er0.2)AlO3,as well as the formation of dense garnet layer at(Y0.2Nd0.2Sm0.2Eu0.2Er0.2)AlO3/Al2 O3 interface,indicate that this new type of high-entropy ceramic is suitable as a candidate environmental barrier coating material for Al2 O3 f/Al2 O3 CMCs.

关键词： High-entropy ceramics (Y0.2Nd0.2Sm0.2Eu0.2Er0.2AlO3 Tri-layer EBC system Low thermal conductivity Al2O3f/Al2O3 CMCs

Evaluating the photovoltaic properties of two conjugated polymers synthesized by Suzuki polycondensation and direct C–H activation

在线全文

学校读者我要写书评

暂无评论

Science China Chemistry 2015年第2期58卷 286-293页

作者： Hedi wei heng Lu Tao Fang Zhishan Bo Beijing Key Laboratory of Energy Conversion and Storage Materials Key Laboratory of Theoretical and Computational PhotochemistryMinistry of Education College of Chemistry Beijing Normal University

Two conjugated polymers HXS-1 and PDFCDTBT were prepared by direct C–H activation and Suzuki polycondensation and their chemical structures were characterized by 1H NMR *** molecular weight of conjugated polymer synthesized by direct C–H activation is lower than the corresponding polymers prepared by Suzuki *** polymers synthesized by direct C–H activation have considerable solubility in common organic solvents and form amorphous *** photovoltaic property of conjugated polymers synthesized by direct C–H activation is inferior to the corresponding polymers synthesized by Suzuki polycondensation.

关键词： polymer solar cells Suzuki polycondensation direct C-H activation conjugated polymers donor materials