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Sintering Densification of Boron Carbide Materials and Their Research Progress

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China's Refractories 2023年第4期32卷 22-27页

作者： ZOU Xin CHEN Ping'an xu guangping LI Xiangcheng ZHU Yingli ZHU Boquan The State Key Laboratory of Refractories and Metallurgy Wuhan University of Science and TechnologyWuhan 430081China Jiangsu Zhonglei Energy-saving Technology Development Co. Ltd.Dongtai 224200China

Boron carbide(B_(4)C)has excellent high-temperature oxidation resistance,high hardness,low relative density,high melting point and excellent abrasive resistance,which is widely used in fields such as refractories,wear-resistant materials and lightweight protective *** research progress and application of B_(4)C materials in China and overseas in recent years were *** influences of sintering processes(pressureless sintering,hot-pressing sintering,hot isostatic pressing sintering,spark plasma sintering and microwave sintering)and sintering additives(simple substances,oxides and carbides)on the B_(4)C densification were *** development of B_(4)C materials was prospected.

关键词： boron carbide refractories densification preparation method sintering additive research progress

Mechanism by which statins influence insulin signaling pathway

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Chinese Medical Journal 2014年第20期127卷 3664-3668页

作者： Li Min Zhang Enyuan Zhang xu Li guangping Department of Cardiology Tianjin Institute of Cardiology SecondHospital of Tianjin Medical University Tianjin 300211 China

Recent studies have shown that statins can influence insulin resistance （IR） in animal models and inhumans.1.2 However, the mechanism by which statins influence the insulin signaling pathway （ISP） remains obscure. It has been proposed that the pleiotropic effects of statins might be involved in regulation of *** phosphatidylinositol 3-kinase （PI3K）-Akt/protein kinase B （PKB） pathway is the main ISE Insulin binding to insulin receptor initiates PI3K-Akt pathway by phosphorylates tyrosine residue of IR substrate proteins （IRSs） including IRS-1 and IRS-2. Activation of the PI3K leads to the accumulation of phosphatidylinositol 3,4,5-triphosphate （PIP3）. PIP3 activates serine/ threonine kinase （Akt）. Glucose transporter-4 （GLUT-4） translocates to plasma membrane from cytosol by serine phosphorylation of Akt and directly regulates glucose metabolism in liver, muscle and adipose tissue （Figure 1）. However, an overall mechanism by which statins influence ISP remained obscure.

关键词： statins mechanisms insulin signaling pathway

Effects of Thallium Stress on Photosynthesis, Chlorophyll Fluorescence Parameters and Antioxidant Enzymes Activities of Coix Lacryma-jobi

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Journal of Environmental Science and Engineering(A) 2017年第1期6卷 15-21页

作者： Gaozhong Pu Denan Zhang Danjuan Zeng guangping xu Yuqing Huang Research Center for Eco-Environmental Sciences Guangxi Key Laboratory of Plant Conservation and Restoration Ecology in KarstTerrain Guangxi Institue of Botany Guangxi Zhuang Autonomous Region and Chinese Academy of Sciences Guilin 541006 China

Levels of T1 （Thallium） in soil from 0 （control） to 50 μg/L through 0.2, 0.5, 1 and 2.5μg/L were directly and positively correlated to levels of T1 in plant tissue, the accumulation being maximum in roots, intermediate in leaves and minimum in stems. Thallium, especially at higher concentrations, adversely affected photosynthesis （as judged based on chlorophyll fluorescence parameters）, suggesting inhibition of photo-activation of PSII （Photosystems II）, and also decreased the rate of photosynthesis, the rate of transpiration and stomatal conductivity drastically. Exposure to TI also increased the activity of CAT （Catalase）（except at 1 μg/L） and POD （Peroxidase）（except at 0.2 μg/L）, suggesting that the antioxidant systems in Coix lacryma-jobi were the main contributors of CAT and SOD （Superoxide Dismutase） and that the tolerance of C. lacryma-jobi to T1 is mainly due to this induced antioxidant machinery.

关键词： Antioxidant enzyme Coix lacryma-jobi L. chlorophyll fluorescence Thallium wetland.

Hydrogen and oxygen compositions of altered rocks from Qixia gold deposit and their genetic significance, Shandong, China

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Chinese Science Bulletin 1999年第S2期44卷 8-9页

作者： ZHAI Jianping, LU Jianjun, HU Kai and xu guangping Department of Earth Sciences, State Key, Laboratory of Mineral Deposits, Nanjing University, 210093, China Department of Earth Sciences State Key Laboratory of Mineral Deposits Nanjing University 210093 China

1 Sample and analytic methods The Qixia gold deposit is one of the important quartz vein-type deposits hosted in metamorphic rockin east Shandong Province, China. About 12 samples were collected at different depths of the Qixia goldmineral district to investigate the variations in the hydrogen and oxygen isotope compositions of alteredrocks. Hydrogen was extracted by melting samples and oxygen was obtained through oxidation by BrF5.The isotope compositions were measured with MAT252, and the precisions for oxygen and hydrogen isotope analyses were±0.2‰ and 2‰, respectively. All the analyses were fulfilled at the State Key *** Mineral Deposit Research in Nanjing University. The δD and δ18O values relative to SMOW are givenin table 1.

关键词： hydrogen and oxygen isotopes altered rocks Qixia gold deposit Shandong.

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胶东煌斑岩的地球化学特征及成因探讨

岩石矿物学杂志 2000年第1期19卷 36-44页

作者：徐红徐光平南京交通高等专科学校南京210018 南京大学成矿机制研究国家重点实验室南京210093

胶东金矿区煌斑岩脉广泛发育 ,这些煌斑岩具有高碱富钾、较高的铝含量、Mg# 值较大等特征 ,岩性相当于玄武质 -玄武安山质的岩石组合。煌斑岩的Cr与Ni、K与Rb、Sr与Ba呈现正相关性 ,其比值接近华北地块上地壳的值 ;煌斑岩全岩的δ1 8O值... 详细信息

胶东金矿区煌斑岩脉广泛发育 ,这些煌斑岩具有高碱富钾、较高的铝含量、Mg# 值较大等特征 ,岩性相当于玄武质 -玄武安山质的岩石组合。煌斑岩的Cr与Ni、K与Rb、Sr与Ba呈现正相关性 ,其比值接近华北地块上地壳的值 ;煌斑岩全岩的δ1 8O值和87Sr/ 86Sr值也较高 ,εNd(t)则呈较大的负值 ,表明煌斑岩的成岩物质来源与地壳有关。胶东群的两阶段部分熔融模式可以较好地解释这类煌斑岩的成因机制。

关键词：煌斑岩岩石化学微量元素金矿区锶同位素

基于写前拷贝CoW的完全快照系统SsMirror设计

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计算机工程 2005年第16期31卷 105-106页

作者：徐光平王刚刘璟南开大学信息技术科学学院天津理工大学计算机系天津300191

磁盘存储子系统层次快照系统SsMirror支持全量快照和增量快照,该文介绍了它的总体设计思想,分析了系统设计的关键数据结构,以及基于写前拷贝技术处理写请求;最后分析了影响系统的因素。

关键词：快照增量快照全量快照写前拷贝位图

Trophic transfer of nanoparticles in food chain:A review

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Trophic transfer of nanoparticles in food chain:A review

Effects of Light Quality on Growth and Physiological Characteristics of Neopyropia yezoensis Free Living Conchocelis

全国环境纳米技术及生物效应学术研讨会

作者： Gaozhong Pu guangping xu Chengxin He Yuqing Huang Guangxi Key Laboratory of Plant Conservation and Restoration Ecology in Karst Terrain Guangxi Institue of BotanyGuangxi Zhuang Autonomous Region and Chinese Academy of Sciences

Nanoparticles from the rapidly increasing number of consumer products have led to concerns about the health risks and environmental impacts of such nanosized materials. One of the most significant and currently not well-understood risks is their potential transfer and magnification in food chains. The present review summarizes and evaluates the characters of nanoparticles, the mechanism, impact factors and models of bioaccumulation and biomagnification of nanoparticles in both terrestrial and aquatic food chain. Differences of these nanoparticles physiological parameters in different groups of terrestrial or aquatic animals are discussed. The potential trophic transfer factor of nanoparticles along terrestrial or aquatic food chains can be predicted based on a simple kinetic equation by incorporating nanoparticles assimilation efficiency（AE）, nanoparticles efflux rate and ingestion activity of the animals. In general, during the transfer of nanoparticles along food chain, whether the concentration of nanoparticles will be biological amplification or dilution, depending on the different food chains and different nanoparticles. Although there are some studies of the bioaccumulation and biomagnification of nanoparticles in food chain, which mostly researched trophic transfer of nanoparticles in a simplified food chain, only a few researchers focused their studies on the integrity food chain. Furthermore, the physicochemical properties of nanoparticles in controlling food chain transfer are generally considered in many past studies, we suggest that the physiological and biochemical processes need to be emphasized in any future study. Therefore, it is necessary to study the bioaccumulation and biomagnification, as well as the related treatment models of nanoparticles in food chain since there are more and more applications of nanoparticles in various fields.

关键词： Food chain Nanoparticles Biomagnification Trophic transfer Nanoecotoxicology

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Asian Agricultural Research 2024年第9期16卷 32-37页

作者： Cuicui TIAN Qinqin LU Yinyin DENG Chuanming HU Wei ZHOU guangping xu Jiangsu Marine Fisheries Research Institute Nantong 226007China

[Objectives]To study the differences of growth rate,morphology,ultrastructure,pigment content and antioxidant enzyme activity of free-living conchocelis of cultivated type of Neopyropia yezoensis under different light qualities(white,red,blue,and green light).[Methods]The study was carried out through light quality design and culture,growth rate determination,microstructure and ultrastructure observation,chlorophyll a content and carotenoid content determination,phycobiliprotein content determination,malondialdehyde(MDA)content determination,superoxide dismutase(SOD)activity determination.[Results]After 21 d of culture,the specific growth rate(SGR)and chlorophyll a content of free-living conchocelis of *** were significantly increased by white light(WL),followed by red light(RL)and green light(GL),and they were the lowest under blue light(BL).Compared with the WL group,the BL group had the highest content of phycoerythrin(PE),and the RL and GL groups had the highest content of phycocyanin(PC).The algal body of WL group was normal black brown,and the cell wall was the *** RL and GL groups,the algal bodies were green,and their diameters and cell wall thicknesses were similar to those in WL *** BL group,the algal body was bright red,the diameter was the smallest,the cell wall was the thinnest,and the ultrastructure showed that the number of plastoglobulus on the thylakoid was the *** BL irradiation,the highest MDA content and the lowest SOD activity were *** results revealed that WL is the most beneficial to the growth of free-living conchocelis,followed by RL and GL,while BL has adverse effects.[Conclusions]This study explored the most suitable light quality conditions for the propagation of free-living *** is expected to provide germplasm guarantee for the production and seedling of ***.

关键词： Neopyropia yezoensis Free-living conchocelis Light quality Growth Physiological characteristics

Effects of mycorrhizal fungi on soil respiration in karst forest

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Effects of mycorrhizal fungi on soil respiration in karst fo...