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牛膝化学成分和药理作用研究进展及其质量标志物(Q-Marker)预测分析

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天然产物研究与开发 2024年第8期36卷 1432-1444页

作者：韩永光谭雅兰张超云卞华河南中医药大学药学院郑州450046 南阳理工学院河南张仲景方药与免疫调节重点实验室南阳473004

牛膝在《神农本草经》中被列为上品,近几年研究证实牛膝的化学成分主要包括甾体、三萜皂苷、多糖、挥发油等化合物,具有抗炎镇痛、调节免疫、抗骨质疏松、保护心血管等药效。本文从牛膝的植物亲缘性,牛膝特有性、有效性、可测性化学成... 详细信息

牛膝在《神农本草经》中被列为上品,近几年研究证实牛膝的化学成分主要包括甾体、三萜皂苷、多糖、挥发油等化合物,具有抗炎镇痛、调节免疫、抗骨质疏松、保护心血管等药效。本文从牛膝的植物亲缘性,牛膝特有性、有效性、可测性化学成分和炮制后化学成分等方面,对牛膝的质量标志物(quality marker,Q-Marker)进行预测分析,牛膝甾酮A、25 S-牛膝甾酮、25 R-牛膝甾酮、齐墩果酸-3-O-β-D-(6′-丁酯)-吡喃葡萄糖醛酸苷、齐墩果酸-3-O-β-D-(6′-甲酯)-吡喃葡萄糖醛酸苷、β-蜕皮甾酮等可作为牛膝质量标志物,为建立牛膝质量评价体系和深入研究其药理作用提供依据。

关键词：牛膝化学成分药理作用质量标志物

Characterizations on Mechanical Properties and In Vitro Bioactivity of Biomedical Ti–Nb–Zr–CPP Composites Fabricated by Spark Plasma Sintering

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Acta Metallurgica Sinica(English Letters) 2016年第11期29卷 1073-1080页

作者： Zheng-Yuan He Lei zhang Wen-Rui Shan Yu-Qin zhang ye-hua Jiang Rong Zhou Jun tan School of Materials Science and Engineering Kunming University of Science and Technology Kunming 650093China National-local Joint Engineering Laboratory of Metal Advanced Solidification Forming and Equipment Technology Kunming 650093 China Engineering Technology Research Center of Titanium Products and Application of Yunnan Province Kunming 650093 China IFW Dresden Institute for Complex MaterialsP.O. Box 27 01 16 01171 Dresden Germany

To alleviate the bio-inert of Ti alloys as hard tissue implants, Ti–35Nb–7Zr–xCPP（calcium pyrophosphate,x = 5, 10, 15, 20 wt%） composites were prepared by mechanical alloying（MA） and following spark plasma sintering（SPS）. Mechanical behaviours and in vitro bioactivity of these composites were investigated systematically. Results showed that the composites consisted of β-Ti matrix, α-Ti, and metal–ceramic phases such as CaO, CaTiO3, CaZrO3, and TixPy. With increasing CPP content, the composites had higher strength（over 1500 MPa） and higher elastic modulus, but suffered almost zero plastic deformation together with lower relative density. When the CPP contents were 5 and 10 wt%,the compressive elastic moduli were 44 and 48 GPa, respectively, which were close to those of natural bones. However, the compressive elastic modulus of the composites increased significantly when CPP contents exceed 10 wt%, thus deteriorating the mechanical compatibility of the composites owing to more α-Ti and metal–ceramic phases. Besides, the surface of Ti–35Nb–7Zr–10CPP composite was deposited as a homogeneous apatite layer during soaking in simulated body fluid（SBF）. It indicates a good bioactivity between the implant materials and living bones.

关键词： Composites Spark plasma sintering Microstructure Mechanical behaviours Bioactivity

Overcoming the limitation of in-situ microstructural control in laser additive manufactured Ti-6Al-4V alloy to enhanced mechanical performance by integration of synchronous induction heating

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Journal of Materials Science & Technology 2021年第35期94卷 32-46页

作者： wei Fan hua tan Fengying zhang Zhe Feng Yongxia Wang Lai-Chang zhang Xin Lin weidong huang State Key Laboratory of Solidification Processing Northwestern Polytechnical UniversityXi'an 710072China Key Laboratory of Metal High Performance Additive Manufacturing and Innovative Design MIIT ChinaNorthwestern Polytechnical UniversityXi'an 710072China School of Material Science and Engineering Chang'an UniversityXi'an 710064China School of Engineering Edith Cowan University270 Joondalup DriveJoondalupPerthWA 6027Australia

Although a variety of processing routes were developed to in-situ manipulate microstructure for fabricating high-performance Ti-6Al-4 V alloy by directed energy deposition(DED),the in-situ microstructural control ability has been limited and lead to a narrowed mechanical property control *** work proved the microstructural correlation betweenβ-grains andα-laths resulting from the unique thermal characteristics of DED for the first time and solved such a dilemma through synchronous induction heating assisted laser deposition(SILD)*** results confirmed that the laser energy and inductive energy have a different effect on the solidification and solid phase transformation *** adjusting the laser-induction parameters,the microstructural correlation can be tuned;theβ-grains andα-laths can be controlled relatively separately,thereby significantly enhancing the ductility of as-deposited sample(elongation from 14.2%to 20.1%).Furthermore,the mechanical properties of the tuned microstructures are even comparable to that of DED Ti-6Al-4 V with post heat treatment,which indicates that the potential of SILD to be a one-step manufacturing process to fabricate high performance components without post heat ***,the tensile testing results of the tuned microstructures indicate thatα-lath size is more influential on the mechanical properties than theβ-grain size due to its stronger hindering effect on the slipping of *** work promotes the understanding of the microstructural formation mechanism in DED titanium alloy and proves that the combination of synchronous induction and laser can expand the ability to control the microstructure and properties of multi-layer deposition.

关键词： Directed energy deposition Additive manufacturing Ti-6Al-4V In-situ microstructural control Mechanical properties

Bioactive phenazines from an earwig-associated Streptomyces sp.

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Chinese Journal of Natural Medicines 2019年第6期17卷 475-480页

作者： HAN Hao GUO Zhi-Kai zhang Bo zhang Mei SHI Jing LI wei JIAO Rui-hua tan Ren-Xiang GE hui-Ming State Key Laboratory of Pharmaceutical Biotechnology Institute of Functional BiomoleculesSchool of Life SciencesNanjing UniversityNanjing 210023China Hainan Provincial Key Laboratory for Functional Components Research and Utilization of Marine Bio-resources Institute of Tropical Bioscience and BiotechnologyChinese Academy of Tropical Agricultural SciencesHaikou 571101China State Key Laboratory Cultivation Base for TCM Quality and Efficacy Nanjing University of Chinese MedicineNanjing 210023China

Three new phenazine-type compounds, named phenazines SA–SC(1–3), together with four new natural products(4–7), were isolated from the fermentation broth of an earwig-associated Streptomyces sp. NA04227. The structures of these compounds were determined by extensive analyses of NMR, high resolution mass spectroscopic data, as well as single-crystal X-ray diffraction measurement. Sequencing and analysis of the genome data allowed us to identify the gene cluster(spz) and propose a biosynthetic pathway for these phenazine-type compounds. Additionally, compounds 1–5 exhibited moderate inhibitory activity against acetylcholinesterase(AChE), and compound 3 showed antimicrobial activities against Micrococcus luteus.

关键词： Earwig-associated actinomycete Phenazine Biosynthetic pathway Antimicrobial activity Acetylcholinesterase inhibitory activity

Study on energy release characteristics of reactive material casings under explosive loading

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Defence Technology（防务技术） 2021年第5期17卷 1791-1803页

作者： Ning Du wei Xiong Tao Wang Xian-feng zhang Hai-hua Chen Meng-ting tan School of Mechanical Engineering Nanjing University of Science&TechnologyNanjingXiaolingwei 200Jiangsu210094China School of Materials Science and Technology Nanjing University of Aeronautics and AstronauticsNanjingYudaojie 29Jiangsu211106China

Reactive Materials(RMs),a new material with structural and energy release characteristics under shockinduced chemical reactions,are promising in extensive applications in national defense and military *** can increase the lethality of warheads due to their dual *** paper focuses on the energy release characteristics of RM casings prepared by alloy melting and casting process under explosive *** experiments of RM and conventional 2A12 aluminum alloy casings were conducted in free field to capture the explosive fireballs,temperature distribution,peak overpressure of the air shock wave and the fracture morphology of fragments of reactive material(RM)warhead casings by using high-speed camera,infrared thermal imager temperature and peak overpressure testing and scanning electron *** showed that an increase of both the fireball temperature and air shock wave were observed in all RM casings compared to conventional 2A12 aluminum ally *** RM casings can improve the peak overpressure of the air shock wave under explosion loading,though the results are different with different charge *** to the energy release characteristics of the RM,increasing the thickness of RM casings will increase the peak overpressure of the near-field air shock wave,while reducing the thickness will increase the peak overpressure of the far-field air shock wave.

关键词： Reactive materials Explosive loading Shock-induced chemical reaction Energy release characteristics Fragmentation

快重离子辐照改性介电聚合物的结构演变与储能性能提升

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硅酸盐学报 2024年第4期52卷 1365-1373页

作者：黄帅康郭鹏张琦忠王文涛谭划张晓东段敬来李飞郭新胡永明张海波华中科技大学材料科学与工程学院材料成形与模具技术国家重点实验室武汉430074 湖北大学铁电压电材料与器件湖北省重点实验室武汉430062 中国科学院近代物理研究所兰州重离子加速器国家实验室兰州450008 西安交通大学电子陶瓷与器件教育部重点实验室西安710049 广东华中科技大学工业技术研究院广州东莞523808

由于薄膜电容器具有低极性,绝缘阻抗高,频率响应宽等优点,具有旁路、去耦、滤波和储能的功能,广泛应用于通信、电子、航空航天、医疗设备、新能源等行业。近年来,由于行业的发展,低介电损耗、高击穿场强与高能量密度的新型介电材料的研... 详细信息

由于薄膜电容器具有低极性,绝缘阻抗高,频率响应宽等优点,具有旁路、去耦、滤波和储能的功能,广泛应用于通信、电子、航空航天、医疗设备、新能源等行业。近年来,由于行业的发展,低介电损耗、高击穿场强与高能量密度的新型介电材料的研发变得愈发重要。采用氙重离子束对聚(偏二氟乙烯–六氟丙烯)进行辐照改性,系统地研究了辐照注量对材料微观结构、介电性能和储能性能的影响。结果表明,^(129)Xe^(27+)快重离子辐照促进了优势相变与表面交联结构形成,提高了材料的储能效率与击穿场强。同时,辐照断键提高了材料的介电常数,增强了有效极化。多种效应协同作用下,成功制备了高击穿场强(540 MV/m)、高放电能量密度(16.3 J/cm^(3))的辐照改性聚合物材料,为促进聚合物介质电容器的发展提供了理论与实验依据。

关键词：快重离子辐照介电材料相变交联储能密度

Stereoselective Construction of Complex Spirooxindoles via Bisthiourea Catalyzed Three-Component Reactions

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Chinese Journal of Chemistry 2018年第12期36卷 1182-1186页

作者： Lin-Lin zhang Ji-wei zhang Shao-hua Xiang Zhen Guo Bin tan College of Material Science & Engineering Taiyuan University of Technol- ogyTaiyuanShanxi 030024China Department of Chemistry South University of Science and Technology of ChinaShenzhenGuangdong 518055China Academy for Advanced Interdisciplinary Studies Southern University of Science and TechnologyShenzhenGuangdong 518055China

A well‐designed three‐component reaction was developed to construct a class of optically active carbazolespirooxindole‐urazoles in good yields with excellent stereoselectivities via tandem Diels‐Alder reaction and ene‐reaction. The driving force originating from aromatization with in situ generated carbazolespirooxindole and the high reactivity of 4‐phenyl‐3 H ‐1,2,4‐triazole‐3,5‐dione facilitate the ene‐reaction in mild conditions. Control experiments indicated that the excellent stereoselectivities of ene‐reaction most likely came from the spatial configuration of the carbazolespirooxindole. The obtained products could be converted to other synthetic useful structures via diverse functionalization.

关键词： multicomponent reactions asymmetric catalysis bisthiourea Diels‐Alder reaction ene‐reaction complex spirooxindoles

Direct Construction of NOBINs via Domino Arylation and Sigmatropic Rearrangement Reactions

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Chinese Journal of Chemistry 2020年第12期38卷 1503-1514页

作者： Ji-wei zhang Liang-Wen Qi Shaoyu Li Shao-hua Xiang Bin tan School of Chemistry and Chemical Engineering Harbin Institute of TechnologyHarbinHeilongjiang 150001China Shenzhen Grubbs Institute and Department of Chemistry Southern University of Science and TechnologyShenzhenGuangdong 518055China Academy for Advanced Interdisciplinary Studies Southern University of Science and TechnologyShenzhenGuangdong 518055China

of main observation and conclusion Privileged 2-amino-2,-hydroxy-l/l,-binaphthyl(NOBIN)frameworks were constructed through a novel domino arylation of naphthylhydroxylamines with diarylhalonium salts and sigmatropic rearrangement in a transition metal-free *** protocol bears broad substrate generality and proceeds under mild reaction conditions,affording diversified NOBINs in high efficiency with absolute regiocontrol during the rearrangement *** active product was accessible by chiral A/-heterocyclic carbene-catalyzed kinetic resolution in one pot or diastereoselective[3,3]-rearrangement guided by a removable chiral ***,diarylchloronium and diarylbrominium salts have been employed as arylation reagents for the first time in assembling such representative biaryl frameworks.

关键词： process. rearrangement salts

Residues of Organochlorine Pesticides(OCPs) in Agricultural Soils of zhangzhou City,China

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Pedosphere 2012年第2期22卷 178-189页

作者： YANG Dan QI Shi-hua zhang Jia-Quan tan Ling-Zhi zhang Jun-Peng zhang Yuan XU Feng XING Xin-Li HU Ying CHEN wei YANG Jun-hua XU Mei-hui State Key Laboratory of Biogeology and Environmental Geology China University of GeoseieneesWuhan 430074(China) School of Environmental Studies China University of GeosciencesWuhan 430074(China) Geological Survey of Fujian Province Fuzhou 350013(China)

A soil survey was conducted in zhangzhou City, an important agricultural region in south of the Fujian Province, China. 93 surface soil samples were collected in the paddy fields, vegetable lands, orchards and tea plantations from zhangzhou City. An additional soil profile was sampled in a paddy field as previous research had indicated high concentrations of organochlorine pesticides （OCPs） in the paddy fields. Dichlorodiphenyltrichloroethanes （DDTs） ranged from 0.64 78.07 ng g-1 dry weight and hexachlorocyclohexanes （HCHs） ranged from 0.72-30.16 ng g-1 dry weight in the surface soil of the whole study region. Ratios of a-HCH/-γ-HCH 〈 4 and o,p′-DDT/p,p′-DDT 〉 1 in all soil samples suggested that lindane and dicofol were widely applied in this region in the past. Concentrations of HCHs and DDTs in soils from the four land use types followed the orders： paddy fields 〉 vegetable lands 〉 tea plantations 〉 orchards and tea plantations 〉 orchards 〉 paddy fields 〉 vegetable lands, respectively. Analyses of the data showed no correlation （r 〈 0.1） between elevation and OCPs contents in paddy fields, orchards and vegetable lands, indicated no significantly different features in distribution of HCHs and DDTs in the soils from low lying plains and mountains and the unsystematic usage of OCPs, and highlighted the fragmented nature of agricultural production in zhangzhou, as well as the reemission of OCPs from the soils, where high OCPs concentrations were found, in Longhai of zhangzhou. In addition, no obvious relationship between the OCPs and total organic carbon （TOC）（r 〈 0.3） was observed in the soil profile. The mean contribution of dicofol in total DDTs was 66% in the whole zhangzhou region. The approximate burdens of HCHs and DDTs in the surface layer of 0-20 em were 0.44 and 1.55 t, respectively. The storage of both HCHs and DDTs in soil surface layer （0-20 cm） accounts for 40% burden of the soil layer of 0 50 cm （1.10 t HCHs and 3.87 t DDTs）, in which the highest conc

关键词： dichlorodiphenyltrichloroethanes (DDTs) hexachlorocyclohexane (HCHs) landform land use types vertical distribution