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One-Pot Stereoselective Synthesis of Different Fused Multicyclic Iminosugars Based on the Iminium-lon Intermediate

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Chinese Journal of Chemistry 2024年第2期42卷 142-150页

作者： song Xie Jilai Wu Likai Zhou Chao Wei Xiaoliu Li hua chen Key Laboratoryof Chemical Biology of Hebei Province College of Chemistry and Material ScienceHebei UniversityBaodingHebei 071002China College of Chemistry and Chemical Engineering Xingtai UniversityXingtaiHebei 054001China

Different novel fused multicyclic iminosugars were synthesized from D-ribose tosylate,aniline and vinyl ethyl ether by one-pot three-component stereoselective[4+2]reaction at different *** iminium-ion is the key intermediate for the *** a result,several complex fused iminosugars 3a were obtained by aza-Diels-Alder mechanism at 60℃,while a series of aza-C-glycosides 5a were prepared by Mannich reaction at room temperature accompanied by another tetrahydroquinoline-fused iminosugars 4a(tricyclic derivatives)through aza-Diels-Alder *** strategy will help to construct structurally diverse and bioactive iminosugar analogues.

关键词： Fused multicyclic iminosugar Aza-Diels-Alder cycloaddition Mannich reaction Tetrahydroquinoline Multicomponent reactions Enantioselectivity Cyclization

Development of an XBP1 agonist,HLJ2,as a potential therapeutic agent for ulcerative colitis

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中国药理学与毒理学杂志 2017年第10期31卷 970-971页

作者： Xiao-nan TANG Hai-jing ZHANG Guang-ming song hua-chen song Wen-jie WANG Lian-qiu WU State Key Laboratory of Bioactive Substances and Functions of Natural Medicines Institute of Materia MedicaChinese Academy of Medical Sciences and Peking Union Medical College

OBJECTIVE To identify the valid targets and new drugs of ulcerative colitis(UC),a recurrent and intractable inflammatory bowel *** and RESULTS In an in vivo mouse model of DSS-induced colitis,HLJ2 decreased weight loss,colon contracture,disease activity index(DAI),colon mucosa damage index(CMDI)and histopathological index(HI).HLJ2 also decreased myeloperoxidase(MPO)activity and reduced production of the inflammatory cytokines TNF-α,IL^(-1)β,and ***2 improved intestinal mucosa damage induced by dextran sodium sulfate(DSS)and increased the expression of ZO-1 and *** 16s rRNA high-throughput sequencing demonstrated a significant improvement in UC intestinal dysbacteriosis in mice treated with HLJ2,including increased abundance of probiotics such as Lachnospiraceae,Prevotellaceae,and *** the same time there was a reduction in the abundance of pathogenic or conditional pathogenic microorganisms such as Bacteroidaceae,Porphyromonadaceae,Deferribacteraceae,and Pseudomonadaceae in HLJ2-treated mice compared with untreated *** Our results demonstrated that the XBP1 agonist HLJ2 inhibits inflammation,regulates the intestinal flora,and protects the intestinal *** is thus a potential therapeutic agent for ulcerative colitis.

关键词： ulcerative colitis XBP1 intestinal flora intestinal mucosa cytokines

Band structures of TiO_2 doped with N, C and B

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2006年第4期7卷 299-303页

作者： XU Tian-hua song chen-lu LIU Yong HAN Gao-rong Department of Materials Science and Engineering Zhejiang University Hangzhou 310027 China

This study on the band structures and charge densities of nitrogen (N)-, carbon (C)- and boron (B)-doped titanium dioxide (TiO2) by first-principles simulation with the CASTEP code (Segall et al., 2002) showed that the three 2p bands of im-purity atom are located above the valence-band maximum and below the Ti 3d bands, and that along with the decreasing of im-purity atomic number, the fluctuations become more intensive. We cannot observe obvious band-gap narrowing in our result. Therefore, the cause of absorption in visible light might be the isolated impurity atom 2p states in band-gap rather than the band-gap narrowing.

关键词： CASTEP code Titanium dioxide Band structure Charge density

Multiple Matching Attenuation Based on Curvelet Domain Extended Filtering

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Journal of Ocean University of China 2024年第4期23卷 924-932页

作者： hua Qingfeng chen Zhang HE Huili TAN Jun chen Haifeng LI Guanbao song Peng ZHAO Bo JIANG Xiuping Key Laboratory of Marine Geology and Metallogeny First Institute of OceanographyMinistry of Natural ResourcesQingdao 266061China Laboratory for Marine Mineral Resources Qingdao Marine Science and Technology CenterQingdao 266237China College of Marine Geoscience Ocean University of ChinaQingdao 266100China BGP Inc. China National Petroleum CorporationZhuozhou 072750China Key Laboratory of Submarine Geosciences and Prospecting Techniques Ministry of EducationQingdao 266100China

The paper develops a multiple matching attenuation method based on extended filtering in the curvelet domain,which combines the traditional Wiener filtering method with the matching attenuation method in curvelet ***,the method uses the predicted multiple data to generate the Hilbert transform records,time derivative records and time derivative records of Hilbert ***,the above records are transformed into the curvelet domain and multiple matching attenuation based on least squares extended filtering is ***,the attenuation results are transformed back into the time-space *** on the model data and field data show that the method proposed in the paper effectively suppress the multiples while preserving the primaries ***,it has higher accuracy in eliminating multiple reflections,which is more suitable for the multiple attenuation tasks in the areas with complex structures compared to the time-space domain extended filtering method and the conventional curvelet transform method.

关键词： multiple matching attenuation curvelet domain extended filtering

Laser powder bed fusion of NiTiFe shape memory alloy via premixed powder:microstructural evolution,mechanical and functional properties

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Rare Metals 2024年第5期43卷 2300-2316页

作者： Bo Yuan Jin-Guo Ge Liang Zhang Hong-Jun chen Long-Sha Wei Yu-Duo Zhou Run-hua song Institute of Intelligent Manufacturing Technology Shenzhen PolytechnicShenzhen 518055China School of Mechanical and Electrical Engineering Guilin University of Electronic TechnologyGuilin 541004China Guangdong Advanced Polymer Composite Engineering Technology Research Center Shenzhen Academy of Aerospace TechnologyShenzhen 518057China Jihua Laboratory Testing Center Jihua LaboratoryFoshan 528000China

High-cost pre-alloyed powder is the bottleneck problem that limits the widespread application of additivemanufactured shape memory *** this work,the lowcost ternary NiTiFe shape memory alloy is fabricated by laser powder bed fusion(LPBF)technique via mechanically mixed pre-alloy NiTi powder and varying contents pure Fe powder(1,2,3 wt%).All NiTiFe alloys show a relative density of up to 99.8%by optimizing the LPBF processing *** to the heterogeneous nucleation effect of micron-sized Fe particles,both grain refinement and texture weakening are generated in the NiTiFe alloys,accompanied by the reduction of dislocation *** the room-temperature mechanical properties,the NiTi-3Fe alloy shows the highest microhardness of HV370,but the fracture strength and elongation reduce to1701 MPa and 23%*** evolution of mechanical properties is attributed to the high internal defects,low dislocation density and the incoherent ***,the NiTi-3Fe alloy shows the quasi-linear superelasticity behavior;the superelastic recoverable strain of NiTi-1Fe and NiTi-2Fe decreased with the increase in Fe *** study provided a new-fangled insight for the development of multi-component NiTi-based shape memory alloys by additive manufacturing.

关键词： Additive manufacturing Shape memory alloy Metal matrix composite Microstructure Mechanical properties

Mn-doped LiFePO_(4)@C as a high-performance cathode material for lithium-ion batteries

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Particuology 2024年第7期90卷 418-428页

作者： Wenjing chen Fangxiang song Yumei Yang Qianlin chen School of Chemistry and Chemical Engineering Guizhou UniversityGuiyang550025China Collaborative Innovation Center of Guizhou Province for Efficient Utilization of Phosphorus and Fluorine Resources Guizhou UniversityGuiyang550025China

In this work,LiFe_(1-x)MnxPO_(4)@C(x=0,0.01,0.02,0.03)cathode materials were obtained by a simple co-precipitation method and heat treatment,and the influence of Mn-doped modification on the electrochemical performance of LiFePO_(4)@C cathode materials was *** show that by doping an appropriate amount of Mn,the cell volume became larger,and the electronic conductivity increased,which improved the Li+diffusion rate and thus its rate capability and cycle performance of Li-ion *** them,LiFe_(0.98)Mn_(0.02)PO_(4)@C showed superior lithium storage capability;the discharge capacity can reach 150.7 mAh g^(−1)at 0.1 *** cell could discharge up to 155.9 mAh g^(−1)at 1 C under high temperature at 45°C,which was higher than LiFePO_(4)@C(142 mAh g^(−1))under the same test *** discharge capacity of 1 C at room temperature was 139.9 mAh g^(−1),and the cycle stability was 95.9%after 200 *** showed that it had good rate capability and excellent cycle *** results indicate that Mn-doped LFP is a simple and effective strategy for developing high-performance cathode materials.

关键词： Mn-doped LiFePO_(4) Lithium-ion battery High temperature

Stereoselective synthesis of substituted 1,3-dienes from propargylic esters: electrophilic-metal or redox catalysis?

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Science China Chemistry 2024年第5期67卷 1384-1396页

作者： Mengfu Dai Liangliang song Liang-An chen Jiangsu Collaborative Innovation Center of Biomedical Functional Materials Jiangsu Key Laboratory of New Power BatteriesSchool of Chemistry and Materials ScienceNanjing Normal UniversityNanjing 210023China Jiangsu Co-Innovation Center of Efficient Processing and Utilization of Forest Resources International Innovation Center for Forest Chemicals and MaterialsCollege of Chemical EngineeringNanjing Forestry UniversityNanjing 210037China

1,3-Diene architectures are not only widely present in natural products, pharmaceuticals, and functional organic materials but also serve as versatile building blocks to furnish important functionalized molecules in synthetic chemistry due to conjugated repeating C=C units. Accordingly, various strategies to access substituted 1,3-dienes in a stereoselective manner have been developed. However, chemo-, regio-and stereoselective synthesis of highly substituted 1,3-dienes still remains elusive and challenging. Readily available propargylic esters have emerged as an appealing class of synthetic intermediates for accessing functionalized 1,3-dienes, especially challenging tri-or tetrasubstituted variants, via transition-metal catalysis, including electrophilic metal and redox neutral catalysis. This review, for the first time, systematically highlights recent advances in transitionmetal catalyzed synthesis of substituted 1,3-dienes from propargylic esters, discusses the mechanisms and synthetic utilities, and gives the remaining challenges and potential opportunities in this field.

关键词： 1 3-diene propargylic ester Lewis acid redox catalysis transition metal

Effect of Ti Particles on the Microstructure and Mechanical Properties of AZ91 Magnesium Matrix Composites

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Acta Metallurgica Sinica(English Letters) 2024年第3期37卷 513-524页

作者： Lu Xiao Ting-Ting Liu Yue Chu Bo song Jie Zhao Xian-hua chen Kai-Hong Zheng Fu-Sheng Pan College of Materials Science and Engineering Chongqing UniversityChongqing 400044China lntelligent Manufacturing and Automobile School Chongqing College of Electronic EngineeringChongqing 401331China School of Materials and Energy Southwest UniversityChongqing 400715China Science and Technology Research Institute of CNNC 404 Co.LTD Gansu 735100China Institute of New Materials Guangdong Academy of SciencesGuangzhou 510650China

Spherical micro-Ti particle(TiP)-reinforced AZ91 magnesium alloy composites were fabricated by semi-solid stirring assisted ultrasonic vibration,which were then subjected to hot *** microstructure results showed that the addition of Ti particles refined the grain size and decreased the texture intensity of the as-extruded AZ91 *** Al3Ti phase with a thickness of 100 nm formed at the Ti/Mg interface,which had a non-coherent relationship with the magnesium *** as-extruded 1 vol.%TiP/AZ91 composite exhibited the best comprehensive mechanical properties,with yield strength,ultimate tensile strength,and elongation at break of 366 MPa,456 MPa,and 14.6%,respectively,which were significantly higher than those of the AZ91 ***,the addition of Ti particles can improve the strength and ductility of the AZ91 alloy,demonstrating the value of magnesium matrix composites for commercial applications.

关键词： Magnesium matrix composites Ti particles Interface Mechanical properties

High-Temperature Mechanical Properties of Shipbuilding Steel BC in Continuous Casting

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Journal of Iron and Steel Research International 2011年第S1期18卷 605-609页

作者： DONG Zhi-hua,chen Deng-fu,song Li-wei,HU Hui,YANG Xing-lei (College of Materials Science and Engineering,Chongqing University,Chongqing 400030,China) Chongqing Univ Coll Mat Sci & Engn Chongqing 400030 Peoples R China

The mechanical property of shipbuilding steel BC has been studied by means of tensile test at various temperatures from 700 ℃ to 1000℃ with theGleeble-1500D thermo-mechanical *** results indicate that the yield strength and tensile strength of steel have an analogous change pattern as temperature decreasing,and the transition in variation rate of strength occurs at 800℃ in both of them;the hot ductility trough of steel BC is a temperature range from 725℃ to 800℃,while the best hot ductility ranges from 875℃ to 1000℃ with the ductility value over 80%.For the sake of understanding the fracture mechanism of the steel,fracture surface and microstructure of the specimens have been examined by scanning electron microscope and metalloscope *** results show that both the second phase particles and the pro-eutectoid ferrite surrounding the austenite boundaries play a significant role to the variation of hot ductility of steel ***,the research is important to the improvement and the further studies on the quality of steel during slab continuous casting process.

关键词： continuous casting slab mechanical property hot ductility microstructure