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Synthesis and antibacterial activity of pleuromutilin derivatives with novel C(14) side chain

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Chinese Chemical Letters 2012年第1期23卷 9-12页

作者： li Qiang Fu Chen Yu ling Xing Sheng Guo hui li he Yu She Yang Shanghai Institute of Materia Medica Chinese Academy of SciencesShanghai 201203China

In order to find novel antibacterial agents with superior antibacterial activity and overcoming multidrug resistance,a series of pleuromutilin derivatives with novel C（14） side chain were synthesized and evaluated for their in vitro antibacterial *** results of antibacterial acticities indicated that most of the derivatives showed potent activities against Gram-positive *** particular,compound lOd exhibited the most potent inhibitory activity compared with pleuromutilin and linezoid,emerged as potential molecule for further investigation.

关键词： Synthesis Pleuromutilin Novel side chains Antibacterial activity

Synthesis and antibacterial activity of C-2(S)-substituted pleuromutilin derivatives

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Chinese Chemical Letters 2010年第5期21卷 507-510页

作者： li Qiang Fu Xing Sheng Guo Xin liu hui li he Yu ling Wang Yu She Yang Shanghai Institute of Materia Medica Chinese Academy of SciencesShanghai 201203China School of Pharmaceutical Engineering Shenyang Pharmaceutical UniversityShenyang 110016China

In order to probe the effect of C-2(S)-substituted groups in the antibacterial activity,a series of novel C-2(S)-substituted pleuromutilin analogues of SB-225586 were synthesized and evaluated for their in vitro antibacterial *** results of antibacterial activities indicated that C-2(S)-substituted pleuromutilin derivatives retained appreciable antibacterial activity,and the 2-fluorination compounds 6a and 6b are more potent than the corresponding 2-hydroxylation analogues 7a and 7b.

关键词： Synthesis Pleuromutilin C-2(S)-substituted Antimicrobial activity

Effect of tungsten carbide particles on microstructure and mechanical properties of Cu alloy composite bit matrix

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Journal of Iron and Steel Research International 2024年第2期31卷 519-530页

作者： Ding-qian Dong Feng-yuan he Xin-hui Chen hui li Kai-hua Shi hui-wen Xiong Xin Xiang li Zhang College of Mechanical Engineering Sichuan University of Science and EngineeringZigong643000SichuanChina State Key Laboratory of Powder Metallurgy Central South UniversityChangsha410083HunanChina Zigong Cemented Carbide Co. Ltd.Zigong643011SichuanChina Material Corrosion and Protection Key Laboratory of Sichuan Province Sichuan University of Science and EngineeringZigong643000SichuanChina

Copper alloy composite bit matrix was prepared by pressureless vacuum infiltration,using at least one of the three kinds of tungsten carbide particles,for example,irregular cast tungsten carbide,monocrystalline tungsten carbide and sintered reduced tungsten carbide *** effects of powder particle morphology,particle size and mass fraction of tungsten carbide on the microstructure and mechanical properties of copper alloy composite were investigated by means of scanning electron microscopy,X-ray diffraction and abrasive wear test in *** results show that tungsten carbide morphology and particle size have obvious effects on the mechanical properties of copper alloy *** tungsten carbide partially dissolved in the copper alloy binding phase,and layers of Cu_(0.3)W_(0.5)Ni_(0.1)Mn_(0.1)C phase with a thickness of around 8–15μm were formed on the edge of the cast tungsten *** 45%irregular crushed fine cast tungsten carbide and 15%monocrystalline cast tungsten carbide were used as the skeleton,satisfactory comprehensive performance of the reinforced copper alloy composite bit matrix was obtained,with the bending strength,impact toughness and hardness reaching 1048 MPa,4.95 J/cm^(2) and 43.6 HRC,*** main wear mechanism was that the tungsten carbide particles firstly protruded from the friction surface after the copper alloy matrix was worn,and then peeled off from the matrix when further wear occurred.

关键词： Polycrystalline diamond compact Pressureless vacuum infiltration Copper alloy composite bit matrix Microstructure characterization Abrasive wear behavior

Synthesis and characterization of non-symmetrical liquid crystals containing a cholesteryl ester moiety

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Chinese Chemical Letters 2009年第5期20卷 562-565页

作者： Duo Wei Zhang Wei Huang Guo hui Pan Wan li he Yu Bo Cao Jin Bao Guo hui Cao Huai Yang Department of Materials Physics and Chemistry School of Materials Science and Engineering University of Science and Technology Beijing Beijing 100083 China

In this paper, a series of chiral non-symmetrical liquid crystals （nBA-chol） consisting of a cholesteryl ester moiety as chiral entity and a biphenyl aromatic core with different terminal alkyl chain has been synthesized and investigated for their liquid crystalline properties. Effects of numbers of methylene units in the terminal alkyl chain on the phase transition temperatures and on the temperature-dependent pitch lengths of the chiral liquid crystals have been studied. The long terminal alkyl chain tends to exhibit smectic A mesophases. The pitch lengths of the cholesteric mesophases of the chiral liquid crystals decrease with increasing temperature and with increasing numbers of methylene units in the terminal alkyl chain, respectively.

关键词： liquid crystals Non-symmetrical Chiral Mesophase Pitch

Tuning heterogeneous microstructures to enhance mechanical properties of nano-TiN particle reinforced Haynes 230 composites by laser powder bed fusion

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Rare Metals 2024年第9期43卷 4548-4565页

作者： Wen-Jie liu hui li Qian-Xing Yin he-Jun Du School of Power and Mechanical Engineering Wuhan University The Institute of Technological Sciences Wuhan University School of Mechanical&Aerospace Engineering Nanyang Technological University

Laser powder bed fusion(LPBF) is considered to be one of the most promising additive manufacturing technologies for producing components with geometries and high geometrical precision that are unattainable by traditional technologies. The superalloy exhibits exceptional mechanical and high-temperature performances,rendering it a prime candidate for advanced aero-engine applications. Despite the high demand for LPBF-manufactured superalloys, the superalloy is one of the materials manufactured difficultly by LPBF due to their large laser absorptivity fluctuation, poor molten pool stability and sharp temperature gradient. hence, superalloys are characterized by severe pores, undesirable coarse columnar grains and poor mechanical properties. In this work, the effect of nano-Ti N particles on defects, molten pool characteristics and microstructure and performance of the composites were investigated. The 4.5 wt% Ti N/Haynes230 samples exhibited exceptional nanohardness and elastic modulus with maximum values reaching 5.53 GPa and 240.03 GPa, respectively. These superior mechanical properties were attributed to the combined effects of spatter and gas pore inhibition, grain refinement and duplex nanophases strengthening. Moreover, the stability of molten pool was enhanced, and spatter was effectively suppressed by adding nano-Ti N particles, while grain refinement and columnar to equiaxed transitions were promoted. Furthermore, the matrix exhibited a high dislocation density due to a significant hindrance of dislocation movement caused by massive nano-phases(e.g., Ti N and M23C6), resulting in the formation of extensive dislocation tangles and *** work offers novel insights into the role of nanoparticles reinforced superalloy composites by LPBF.

关键词： Composites Laser powder bed fusion Mechanical properties Microstructure Molten pool characteristics

Overexpression of mclca3 in airway epithelium of asthmatic murine models with airway inflammation

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Chinese Medical Journal 2010年第12期123卷 1603-1606页

作者： ZHANG hui-lan he li Department of Respiratory Diseases Tongji Hospital TongjiMedical College Huazhong University of Science and TechnologyWuhan Hubei 430030 China

Asthma is a worldwide prevalent disease that is a .considerable health burden in many countries. In recent years, the airway epithelium is increasingly recognized as a central contributor to the pathogenesis of asthma. One of the most highly induced genes in epithelial ceils in experimental allergic airway disease is the third murine calcium-activated chloride channel homologue （mclca3, alias gob-5）. Its human homology protein is hCLCA, which has been identified as clinically relevant molecules in diseases with secretory dysfunctions including asthma and cystic fibrosis.

关键词： asthma airway epithelial cell mclca3 inflammation

Two-photon polymerization-based 4D printing and its applications

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International Journal of Extreme Manufacturing 2024年第1期6卷 1-25页

作者： Bingcong Jian Honggeng li Xiangnan he Rong Wang hui Ying Yang Qi Ge Shenzhen Key Laboratory of Soft Mechanics&Smart Manufacturing Southern University of Science and TechnologyShenzhen 518055People’s Republic of China Department of Mechanical and Energy Engineering Southern University of Science and TechnologyShenzhen 518055People’s Republic of China Pillar of Engineering Product Development Singapore University of Technology and Design8 Somapah RoadSingapore 487372Singapore

Two-photon polymerization(TPP)is a cutting-edge micro/nanoscale three-dimensional(3D)printing technology based on the principle of two-photon *** surpasses the diffraction limit in achieving feature sizes and excels in fabricating intricate 3D micro/nanostructures with exceptional *** concept of 4D entails the fabrication of structures utilizing smart materials capable of undergoing shape,property,or functional changes in response to external stimuli over *** integration of TPP and 4D printing introduces the possibility of producing responsive structures with micro/nanoscale accuracy,thereby enhancing the capabilities and potential applications of both *** paper comprehensively reviews TPP-based 4D printing technology and its diverse ***,the working principles of TPP and its recent advancements are ***,the optional4D printing materials suitable for fabrication with TPP are ***,this review paper highlights several noteworthy applications of TPP-based 4D printing,including domains such as biomedical microrobots,bioinspired microactuators,autonomous mobile microrobots,transformable devices and robots,as well as anti-counterfeiting *** conclusion,this paper provides valuable insights into the current status and future prospects of TPP-based4D printing technology,thereby serving as a guide for researchers and practitioners.

关键词： two-photonpolymerization 4D printing nano/micro fabrication microrobot

CO_(2) corrosion of X80 steel welded joints under micro-turbulence induced by welding reinforcement height

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Journal of Iron and Steel Research International 2024年第4期31卷 1015-1032页

作者： Xiao-hui Dou Bin li Zong-hao he Xin-wei Zhang Da-lei Zhang Yan li School of Materials Science and Engineering China University of Petroleum(East China)Qingdao 266580ShandongChina School of Energy and Power Engineering Jiangsu UniversityZhenjiang 212013JiangsuChina

Corrosion failure accidents owing to flow erosion and pipeline corrosion frequently occur during *** welding reinforcement height(WRH)can induce locally micro-turbulent flow field,which aggravates local corrosion of welded joints.A high wall shear stress(WsS)experimental setup was established to conduct the online electrochemical corrosion *** influence of WRH sizes on local corrosion of welded joints was studied at different flow *** electrochemical signals of the local corrosion of X80 welded joints at different flow rates were monitored in real time using electrochemical impedance spectroscopy and wire beam *** addition,the corrosion products composition and properties were *** results show that the micro-turbulent flow fields induced by the WRHs can enhance ion mass transfer near the welded *** corrosion products on the WRH surface also present different microscopic morphologies at different flow *** strong flow fields,the locally enhanced wsS can peel off the dense corrosion product partially,leading to the electrochemical distribution of large cathode and small anode,which accelerates the occurrence and development processes of the local corrosion of welded *** scientific guidelines for the corrosion protection of long-distance oil and gas pipelines can be potentially provided.

关键词： X80 steel welded joint Welding reinforcement height Micro-turbulence CO_(2)corrosion-Ion mass transfer

Immune checkpoint inhibitors break whose heart? Perspectives from cardio-immuno-oncology

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Genes & Diseases 2024年第2期11卷 807-818页

作者： Yingying he hui Yu Shuang Dai Miao he ling Ma Zihan Xu Feng Luo li Wang Oncology Department Deyang People's HospitalDeyangSichuan 618000China Department of Medical Oncology Lung Cancer CenterWest China HospitalSichuan UniversityChengduSichuan 610000China Cardiovascular Department Mianyang Central HospitalMianyangSichuan 621000China Department of Rheumatology and Immunology Deyang People's HospitalDeyangSichuan 618000China

Immune checkpoint inhibitors (ICIs) are monoclonal antibody antagonists,which can block cytotoxic T lymphocyte antigen-4 (CTLA-4),programmed death-1/ligand-1 (PD-1/PD-L1) pathways,and other molecules exploited by tumor cells to evade T cell-mediated immune *** have transformed the treatment landscape for various cancers due to their amazing *** anti-tumor therapies,including targeted therapy,radiotherapy,and chemotherapy,combine ICIs to make the treatment more ***,the off-target immune activation caused by ICIs may lead to a broad spectrum of immune-related adverse events (irAEs) affecting multiple organ *** irAEs,cardiotoxicity induced by ICIs,uncommon but fatal,has greatly offset survival benefits from ICIs,which is heartbreaking for both patients and ***,such cardiotoxicity requires special vigilance,and it has become a common challenge both for patients and *** article reviewed the clinical manifestations and influence of cardiotoxicity from the view of patients and clinicians,elaborated on the underlying mechanisms in conjunction with animal studies,and then attempted to propose management strategies from a cardio-immuno-oncology multidisciplinary perspective.

关键词： Cancer management Cardio-immuno-oncology multidisciplinary Cardiotoxicity Immune checkpoint inhibitors Immune tolerance