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Direct oxidative C(sp^3)-H cyanation of secondary benzylic ethers

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Chinese Chemical Letters 2019年第6期30卷 1241-1243页

作者： Zehua Wang ying Mao Honghao Guan Min Cao Jing Hua Lei Feng Lei liu School of Chemistry and Chemical Engineering Shandong University Ji'nan 250100 China School of Pharmaceutical Sciences Shandong University Ji'nan 250012 China State Key Laboratory for Chemistry and Molecular Engineering of Medicinal Resources School of Chemistry and Pharmaceutical Sciences of Guangxi Normal University Guilin 541004 China

Current studies on the oxidative C--H functionalization of benzylic ethers for C--C forging process dominantly focus on primary ethers. The corresponding reaction of secondary ethers remains underdeveloped. Herein, a practical and efficient oxidative C--H cyanation of secondary benzylic ethers with TMSCN in the presence of DDQ is described. The metal-free process is well tolerated with a wide variety of electronically varied α-monosubstituted isochromans, facilely furnishing a library of isochromans bearing α-aryl α-cyano substituent patterns for further diversification and bioactive small molecule identification.

关键词： C-H functionalization Cyanation Oxidation Secondary ether Tertiary ether synthesis

Microstructure and Properties of Ti and Ti+Nb Ultra-Low-Carbon Bake Hardened Steels

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Journal of Iron and Steel Research International 2009年第6期16卷 33-40页

作者： CHEN Ji-ping KANG Yong-lin HAO ying-min liu Guang-ming XIONG Ai-ming School of Materials Science and Engineering University of Science and Technology Beijing State Key Laboratory for Advanced Metals and Materials Beijing 100083 China Shougang Research Institute of Technology Beijing 100041 China

Hot rolling, cold rolling and continuous annealing processes of Ti bearing and Ti＋ Nb stabilized ultra-low-carbon bake hardened steels were experimentally studied. The microstructure and texture evolution, as well as the morphology, size and distribution of second phase precipitates during hot rolling, cold rolling and continuous annealing were also analyzed. The results showed that the size of NbC precipitates in Ti＋Nb stabilized ultra-low-carbon bake hardened steel was smaller than that of TiC precipitates in Ti bearing ultra-low-carbon bake hardened steel, which made the average grain size of Ti＋ Nb stabilized ultra-low-carbon bake hardened steel finer than that of Ti bearing ultra-low-carbon bake hardened steel; for the yield strength, the former was higher than the latter; but for the r value which reflects the deep-drawing performance, the former was lower than the latter.

关键词： ultra-low-carbon bake hardened steel texture microstructure mechanical property

Effect of Heat Treatment on Microstructure and Mechanical Behavior of Cu-Bearing 316L Stainless Steel Produced by Selective Laser Melting

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Acta Metallurgica Sinica(English Letters) 2024年第1期37卷 169-180页

作者： Huan Yang ying liu Jianbo Jin Kunmao Li Junjie Yang Lingjian Meng Chunbo Li Wencai Zhang Shengfeng Zhou Sino-German College of Intelligent Manufacturing Shenzhen Technology UniversityShenzhen518118China Institute of Advanced Wear and Corrosion Resistance and Functional Materials Jinan UniversityGuangzhou510632China Department of Orthopedics First Affiliated Hospital of Jinan UniversityGuangzhou510632China

Cu-bearing stainless steels(SSs)with high strength,excellent plasticity,and effective antimicrobial properties hold significant potential for applications in the marine *** this study,Cu-bearing SSs with copper ranging from 0 to 6.0 wt%were successfully prepared using selective laser melting(SLM)*** the Cu-bearing SSs with different copper contents,the effect of heat treatment on the microstructural and mechanical behaviors was studied *** observations revealed that the subgrain size of Cu-bearing SSs increased with heat treatment at 500℃ and 700℃ for 6 ***,the tensile strength and elongation increased after the heat treatment temperature due to the combined effect of dislocations,twins,andε-Cu precipitated ***,after heat treatment at 700℃,the SLM4.5Cu sample exhibited an abnormal rise in tensile strength and *** finding suggests that the diffusion strengthening caused byε-Cu precipitates exceeded the stacking fault ***,the tensile strength and elongation reached 693.32 MPa and 56.94%,*** work provides an efficient approach for preparing Cu-bearing SSs with exceptional strength and plasticity.

关键词： Selective laser melting Cu-bearing stainless steel(SS) Heat treatment Mechanical properties

Inhibiting 5-hydroxytryptamine receptor 3 alleviates pathological changes of a mouse model of Alzheimer's disease

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Neural Regeneration Research 2023年第9期18卷 2019-2028页

作者： Li-Fen liu Yu-Tong liu Dan-Dan Wu Jie Cheng Na-Na Li Ya-Ni Zheng liang Huang Qiong-Lan Yuan Department of Neurology Shanghai Tongji HospitalTongji University School of MedicineShanghaiChina Department of Radiology University of Nebraska Medical CenterOmahaNEUSA Department of Human Anatomy Histology&EmbryologyTongji University School of MedicineShanghaiChina

Extracellular amyloid beta(Aβ) plaques are main pathological feature of Alzheimer’s ***,the specific type of neuro ns that produce Aβ peptides in the initial stage of Alzheimer’s disease are *** this study,we found that 5-hydroxytryptamin receptor 3A subunit(HTR3A) was highly expressed in the brain tissue of transgenic amyloid precursor protein and presenilin-1 mice(an Alzheimer’s disease model) and patients with Alzheimer’s *** investigate whether HTR3A-positive interneurons are associated with the production of Aβ plaques,we performed double immunostaining and found that HTR3A-positive interneurons were clustered around Aβ plaques in the mouse *** amyloid precursor protein-positive or β-site amyloid precursor protein cleaving enzyme-1-positive neurites near Aβ plaques were co-localized with HTR3A *** results suggest that HTR3A-positive interneurons may partially contribute to the generation of Aβ *** treated 5.0-5.5-month-old model mice with tro pisetron,a HTR3 antagonist,for 8 consecutive *** found that the cognitive deficit of mice was partially reversed,Aβ plaques and neuroinflammation we re remarkably reduced,the expression of HTR3 was remarkably decreased and the calcineurin/nuclear factor of activated T-cell 4 signaling pathway was inhibited in treated model *** findings suggest that HTR3A interneurons partly contribute to generation of Aβ peptide at the initial stage of Alzheimer’s disease and inhibiting HTR3 partly reve rses the pathological changes of Alzheimer’s disease.

关键词： 5-hydroxytryptamin receptor 3 Alzheimer’s disease amyloid beta plaques calcineurin cognitive deficits HTR3 interneurons iCa2+ nuclear factor of activated T-cells transgenic amyloid precursor protein and presenilin-1 mice tropisetron

Current situation and human health risk assessment of fluoride enrichment in groundwater in the Loess Plateau:A case study of Dali County,Shaanxi Province,China

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China Geology 2021年第3期4卷 487-497页

作者： Rui-ping liu Hua Zhu Fei liu ying Dong Refaey M El-Wardany Xi’an Center China Geological SurveyMinistry of Natural ResourcesXi’an 710054China Key Laboratory of Subsurface Hydrology and Ecological Effects in Arid Region Ministry of EducationXi’an 710054China Key Laboratory for Geo-hazards in Loess Area Ministry of Natural ResourcesXi’an 710054China Field Base of Scientific Observation of Shaanxi Tongguan Ministry of Natural ResourcesXi’an 710054China Dalian ocean and fishery comprehensive administration supervision lochus Dalian 116000China Assiut Branch Al-Azhar UniversityAssiut 71524Egypt

This study aims to investigate the mechanisms and health risks of fluoride enrichment in groundwater in the Loess Plateau,*** taking Dali County,Shaanxi Province,China as an example,this study obtains the following results through field investigation and the analyses of water,soil,and crop samples.(1)The groundwater can be divided into two major types,namely the Quaternary pore-fissure water and Karst *** Karst area and sandy area have high-quality groundwater and serve as the target areas for optional water *** groundwater in the study area is slightly alkaline and highly ***,high-fluoride groundwater is mainly distributed in the loess and river alluvial plains in the depression area of the Guanzhong Basin and the discharge areas of the groundwater,with the highest fluoride concentration exceeding seven times the national standard.(2)Fluoride in groundwater mainly originates from a natural source and human *** natural source refers to the fluoride-bearing minerals in rocks and soil,and the fluoride from this source is mainly controlled by natural factors such as climate,geologic setting,pH,specific hydrochemical environment,ion exchange,and mineral *** activities in modern life can be further divided into industrial and agricultural sources primarily.(3)The health risks of fluoride contamination are very high in the Loess Plateau,especially for children compared to ***,the risks of fluoride exposure through food intake are higher than those through drinking water *** authors suggest selecting target areas to improve water supply and ensure the safety of drinking water in the study ***,it is necessary to plant crops with low fluoride content or cash crops and to conduct groundwater treatment to reduce the fluoride concentration in drinking *** results will provide a theoretical basis for safe water supply in the faulted basin areas in the Loess Plateau.

关键词： Fluoride Groundwater Human health risks Loess Plateau Hydrogeological survey engineering Dali County Shaanxi Province China

Giant Magneto-Impedance Effect in As-Deposited Multilayered Amorphous Films

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Chinese Physics Letters 1999年第6期16卷 452-454页

作者： XIAO Shu-qin liu De-zhen liu Yi-hua DAI You-yong ZHANG Lin MEI liang-mo Department of Physics Shandong UniversityJi'nan 250100 College of Materials Science and Engineering Shandong University of TechnologyJi'nan 250014

Giant magneto-impedance effects have been observed in as-deposited amorphous FeCuNbSiB/Cu/FeCuNbSiB and FeCuNbSiB/SiO_(2)/Ag/SiO_(2)/FeCuNbSiB multilayered *** films were deposited onto Si substrates by radio frequency *** FeCuNbSiB/Cu/FeCuNbSiB films,maximum giant magneto-impedance ratios as large as 32%and 11%were obtained at 13 MHz in the longitudinal and transverse fields,*** FeCuNbSiB/SiO_(2)/Ag/SiO_(2)/FeCuNbSiB films,the maximum giant magneto-impedance ratios were 47%and 57%at the same frequency for the two cases,which are much larger than those obtained in the annealed single layer Hlms.

关键词： impedance amorphous transverse

Influence of Heat Treatment Temperature on Microstructure and Property of 00Cr13Ni5Mo2 Supermartensitic Stainless Steel

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Journal of Iron and Steel Research International 2014年第3期21卷 364-368页

作者： De-ning ZOU Xiao-hua liu ying HAN Wei ZHANG Jiao LI Kun WU School of Metallurgy and Engineering Xi'an University of Architecture and Technology Key Laboratory of Advanced Structural Materials of Ministry of Education Changchun University of Technology State Key Laboratory for Mechanical Behavior of Materials Xi'an Jiaotong University

The microstructural evolution and mechanical property of 00Crl3NiSMo2 supermartensitic stainless steel （SMSS） subjected to different heat treatments were investigated. Room tensile tests, hardness tests, scanning elec- tron microscopy, transmission electron microscopy and X ray diffraction were conducted on the heat-treated steels. It is found that the microstructure of the heat-treated steel is composed of tempered lath martensite, retained austenite and ^-ferrite. The austenitizing temperature and tempering temperature have a significant effect on the microstrtlctur al changes, which leads to the complex variations of mechanical properties. The fine tempered lath martensite and more dispersed reversed austenite in the microstructure facilitate improving the comprehensive mechanical properties of the studied steel. The optimal heat treatment process of 00Crl3Ni5Mo2 SMSS is obtained by austenitizing at 1000 ℃ for 0.5 h＋air cooling followed by tempering at 630 ℃ for 2 h＋air cooling, where the excellent combination of ten- sile strength, elongation and hardness can be achieved.

关键词： supermartensitic stainless steel heat treatment microstructure mechanical property reversed austenite

Schisandra lignans ameliorate nonalcoholic steatohepatitis by regulating aberrant metabolism of phosphatidylethanolamines

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Acta Pharmaceutica Sinica B 2023年第8期13卷 3545-3560页

作者： Lijuan Xue Keanqi liu Caixia Yan Junling Dun Yexin Xu Linlin Wu Huizhu Yang Huafang liu Lin Xie Guangji Wang Yan liang Key Lab of Drug Metabolism&Pharmacokinetics State Key Laboratory of Natural MedicinesChina Pharmaceutical UniversityNanjing 210009China Zhejiang Provincial Key Laboratory for Drug Evaluation and Clinical Research Department of Clinical Pharmacythe First Affiliated HospitalZhejiang University School of MedicineHangzhou 310003China Analytical Applications Center Shimadzu(China)Co.Ltd.Shanghai 200233China

Nonalcoholic steatohepatitis(NASH)is a spectrum of chronic liver disease characterized by hepatic lipid metabolism *** reports emphasized the contribution of triglyceride and diglyceride accumulation to NASH,while the other lipids associated with the NASH pathogenesis remained *** specific purpose of our study was to explore a novel pathogenesis and treatment strategy of NASH via profiling the metabolic characteristics of ***,multi-omics techniques based on LC—Q-TOF/MS,LC—MS/MS and MS imaging were developed and used to screen the action targets related to NASH progress and treatment.A methionine and choline deficient(MCD)diet-induced mouse model of NASH was then constructed,and Schisandra lignans extract(SLE)was applied to alleviate hepatic damage by regulating the lipid metabolism-related enzymes CES2A and *** lipidomics indicated that MCD-diet led to aberrant accumulation of phosphatidylethanolamines(PEs),and SLE could significantly reduce the accumulation of intrahepatic ***,exogenous PE(18:0/18:1)was proved to significantly aggravate the mitochondrial damage and hepatocyte *** PE(18:0/18:1)also deteriorated the NASH progress by up regulating intrahepatic proinflammatory and fibrotic factors,while PE synthase inhibitor exerted a prominent hepatoprotective *** current work provides new insights into the relationship between PE metabolism and the pathogenesis of NASH.

关键词： Nonalcoholic steatohepatitis Multi-omics Schisandra lignans extract Phosphatidyle thanolamine PE(18:0/18:1)

Diffusive gradients in thin films(DGT) probe for effectively sampling of per-and polyfluoroalkyl substances in waters and sediments

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Journal of Environmental Sciences 2022年第11期34卷 90-97页

作者： Yuanyuan Yang Sisi liu Runmei Wang Cailin Li Jianhui Tang Tao Chen Guang-Guo ying Chang-Er Chen Environmental Research Institute/School of Environment Guangdong Provincial Key Laboratory of Chemical Pollution and Environmental Safety&MOE Key Laboratory of Theoretical Chemistry of EnvironmentSouth China Normal UniversityGuangzhou 510006China Key Laboratory of Coastal Environmental Processes and Ecological Remediation Yantai Institute of Coastal Zone ResearchChinese Academy of SciencesYantai 264003China

The passive sampling technique, diffusive gradients in thin films(DGT) has attracted increasing interests as an in-situ sampler for organic contaminants including per-and polyfluoroalkyl substances(PFAS). However, its effectiveness has been questioned because of the small effective sampling area(3.1 cm^(2)). In this study, we developed a DGT probe for rapid sampling of eight PFAS in waters and applied it to a water-sediment system. It has a much larger sampling area(27 cm^(2)) and as a result lower method quantification limits(0.15 –0.21 ng/L for one-day deployment and 0.02 – 0.03 ng/L for one-week deployment) and much higher(by > 10 factors) sampling rate(100 m L/day) compared to the standard DGT(piston configuration). The sampler could linearly accumulate PFAS from wastewater, was sensitive enough even for a 24 hr deployment with performance comparable to grab sampling(500m L). The DGT probe provided homogeneous sampling performance along the large exposure area. The use of the probe to investigate distributions of dissolved PFAS around the sediment-water interface was demonstrated. This work, for the first time, demonstrated that the DGT probe is a promising monitoring tool for trace levels of PFAS and a research tool for studying their distribution, migration, and fate in aquatic environments including the sediment-water interface.

关键词： Diffusive gradients in thin films(DGT) Passive sampling Per-and polyfluoroalkyl substances(PFAS) Sediment Aquatic environments