检索结果-南通市图书馆

Journal of Environmental Sciences 2005年第5期17卷 722-726页

作者： SUN Yang-zhao WANG Xue-tong li xing-hong XU Xiao-bai State Key Laboratory of Environmental Chemistry and Ecotoxicology Research Center for Eco-Environmental Sciences Chinese Academy of SciencesBeijing 100085 China

The concentration of organochlorine pesticides（OCPs） in tissues and organs of silver carp（Hypophthalmichthys mofitrix） from Guanting Reservoir were investigated to evaluate the pollution potential and distribution of OCPs. A total of 16 OCPs were measured and the concentrations were in the range of 1.61-69.01 ng/g wet weight（ww） for total OCPs, 0.16- 0.75 ng/g ww for HCB. 0.75 -26.80 ng/g ww for SHCH（sum of α-,β-, γ- and δ-HCH） and 0.68-35.94 ng/g ww for SDDT（ sum of p, p＇-DDE, p, p＇-DDD, o, p＇-DDT and p, p＇- DDT）. The mean concentrations of total OCPs, HCB, ∑HCH, and ∑DDT were 18.04, 0.96, 7.14 and 9.28 ng/g ww, respectively. Among the organochlorine pesticides, β-HCH and p, p＇-DDE were the most dominant compounds in tissue and organ with the average concentrations of 4.42 and 8.14 ng/g, respectively. The results obtained in this study show that the levels of 16 OCP residues found in silver carps are low and pose no threat to human health and wildlife fed upon them on the basis of existing related quality guidelines. However, recent input of lindane and DDT might still exist in the area investigated and further investigation should be carried on.

关键词： organochlorine pesticides silver carp distribution Guanting Reservoir

Polycyclic aromatic hydrocarbon in urban soil from Beijing, China

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Journal of Environmental Sciences 2006年第5期18卷 944-950页

作者： li xing-hong MA ling-ling liU Xiu-fen FU Shan CHENG Hang-xin XU Xiao-bai State Key Laboratory of Environmental Chemistry and Ecotoxicology Research Center for Eco-Environmental Sciences Chinese Academy of Sciences Beijing 100085 China Institute of Geophysical and Geochemical Exploration Langfang 065000 China

Polycyclic aromatic hydrocarbons （EPA-PAHs） in the urban surface soils from Beijing were determined using gas chromatography and mass spectrometry （GC-MS）. It is significantly complementary for understanding the PAHs pollution in soil of integrated Beijing city on the basis of the information known in the outskirts. The total concentration of 16 EPA-PAH was from 0.467 to 5.470 μg/g and was described by the contour map. Compound profiles presented that the 4-, 5- and 6-ring PAHs were major compositions. The correlation analysis showed that PAHs have the similar source in the most sampling sites and BaP might be considered as the indicator of PAHs. Characteristic ratios of anthracene （An）/（An＋ phenanthrene （Phe））, fluoranthene （Flu）/（Flu/ pyrene （Pyr）） and benzo[a]pyrene （BaP）/laenzo[g,h,i]perylene （BghiP） indicated that the PAHs pollutants probably mainly originated from the coal combustion and it was not negligible from vehicular emission. The level of PAHs in our study area was compared with other studies.

关键词： PAHs urban soil source Beijing

Numerical analysis of loaded stress and central displacement of deep groove ball bearing

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Journal of Central South University 2016年第10期23卷 2542-2549页

作者：杨磊邓松李红星 Hubei Key Laboratory of Advanced Technology for Automotive Components Wuhan University of Technology Wuhan 430070 China Hubei Collaborative Innovation Center for Automotive Components Technology Wuhan University of Technology Wuhan 430070 China Zhejiang Tianma Bearing Co. Ltd. Hangzhou 310015 China

The aim of this work is to develop a three-dimensional model of deep groove ball bearing to investigate the loaded stresses and central displacements of bearing rings. The equivalent stresses and central displacements of bearing rings are obtained based on the simulated analysis. Moreover, several parameters, such as load magnitude, raceway groove curvature radius(RGCR), thicknesses of outer and inner rings, are varied to investigate their effects on the equivalent stresses and central displacements of bearing rings. Research results provide useful guidelines for determining the design parameters.

关键词： deep groove ball bearing equivalent stress central displacement

Successful Pregnancy following Transfer of Embryo with Dissolved Zona Pellucida

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Reproductive and Developmental Medicine 2020年第1期4卷 60-62页

作者： li hong-xing Reproductive Medicine Centre the First Hospital of Lanzhou UniversityLanzhou 730000China Key Laboratory for Reproductive Medicine and Embryo of Gansu Lanzhou 730000China

This study aimed to describe a case of a patient with the spontaneous dissolution of zona pellucida(ZP)during cleavage embryo development after intracytoplasmic sperm injection(ICSI).This patient experienced early abortion due to fetal chromosome 8 abnormality and received ICSI at 31 years of ***-lapse monitoring of embryo cleavage and blastocyst culture was performed,and we found that the ZP of embryos 1,2,4,and 5 dissolved gradually during the cleavage stage of embryo *** blastocysts that developed from 2 pronuclear zygotes were analyzed using next-generation sequencing,and one frozen-thawed blastocyst was transferred,resulting in intrauterine *** results of amniotic fluid puncture showed normal fetal *** our knowledge,this is the first report of ZP dissolution during the cleavage-stage embryo;however,the exact mechanism remains *** morphological changes inferred that the granular matter in the periocular space was related to the dissolution of ZP through time-lapse observation.

关键词： Blastocyst Transfer Intracytoplasmic Sperm Injection Next-Generation Sequencing Zona Pellucida Dissolution

Adenovirus-mediated expression of pig α(1,3) galactosyltransferase reconstructs Gal α(1,3) Gal epitope on the surface of human tumor cells

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Cell Research 2001年第2期11卷 116-124页

作者： xing li, GUO hong XIA, JIAN FEI, FANG HUANG, li HE GUO Institute of Biochemistry and Cell Biology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai 200031, China Institute of Biochemistry and Cell Biology Shanghai Institutes for Biological Sciences Chinese Academy of Sciences Shanghai China

Gal α(1, 3) Gal (gal epitope) is a carbohydrate epitope and synthesized in large amount by α(1, 3) galactosyltransferase [α(1, 3) GT] enzyme on the cells of lower mammalian animals such as pigs and mice. Human has no gal epitope due to the inactivation of α(1, 3) GT gene but produces a large amount of antibodies (anti-Gal) which recognize Gal α(1, 3) Gal structures specifically. In this study, a replication deficient recombinant adenoviral vector Ad5sGT containing pig α(1, 3) GT cDNA was constructed and characterized. Adenoviral vector-mediated transfer of pig α(1, 3) GT gene into human tumor cells such as malignant melanoma A375, stomach cancer SGC-7901, and lung cancer SPC-A-1 was reported for the first time. Results showed that Gal epitope did not increase the sensitivity of human tumor cells to human complement-mediated lysis, although human complement activation and the binding of human IgG and IgM natural antibodies to human tumor cells were enhanced significantly after Ad5sGT transduction. Appearance of gal epitope on the human tumor cells changed the expression of cell surface carbohydrates reacting with Ulex europaeus I (UEA I) lectins, Vicia villosa agglutinin (VVA), Arachis hypogaea agglutinin (PNA), and Glycine max agglutinin (SBA) to different degrees. In addition, no effect of gal epitope on the growth in vitro of human tumor cells was observed in MTT assay.

关键词： Adenoviral vector galactosyltransferase Gal α(1 3) Gal gene expression human tumor cell.

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自制煤气发生炉在铸钢件热处理炉上的使用

铸造 2007年第5期56卷 532-534页

作者：李宏兴河北省清苑县朝阳铸造有限公司河北清苑071100

叙述了自制煤气发生炉在铸钢件热处理炉上的使用情况,总结出了详细的操作经验,说明通过合理的操作和热风供氧,该炉的使用效果与其他工业炉比较,具有节能、高效、环保的优点。

关键词：热处理 .铸钢件温度

Low dose effects on cultured mammalian cells...

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Nuclear Science and Techniques 2000年第4期11卷 276-279页

作者： WANG Ju-Fang, li Wen-Jian, ZHOU Guang-Ming, HE Jing, li Qiang, DANG Bing-Rong, li xing-lin, XIE hong-Mei, WEI Zeng-Quan (Institute of Modern Physics, the Chinese Academy of Sciences, Lanzhou 730000) 中科院近代物理所甘肃兰州 730000

The low dose effects induced by carbon ions on Chinese hamster V79 cells and murine melanoma B16 cells were investigated in this paper. Both cell lines were divided into four groups for irradiation: (1) control, (2) 0.02 Gy or 0.05 Gy(D1), (3) 1 Gy(D2), (4) D1+D2. The survivors and micronuclei were studied as biological endpoints. The results of group (1) and group (2) showed that there were no obvious differences on micronucleus frequency but there were significant increases when irradiation dose was 0.02Gy on colony formation efficiency. Although low dose ion irradiation could not contribute to DNA damages, it could enhance the colony formation efficiency. In the study of group (3) and (4), when the ion dose was 0.02 Gy, there were evident increases on surviving fraction and decreases on micronucleus frequency, but there were no statistical changes on these endpoints when the ion dose was 0.05Gy. This meant that high LET radiation could induce the adaptive response of cultured cells, furthermore, in the range of inducing ion dose , low dose irradiation was more profitable than high dose one.

关键词：哺乳动物细胞 DNA 离子辐射低剂量效应辐射效应碳离子

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输入空间新划分下模糊控制系统的稳定性

控制理论与应用 2010年第11期27卷 1511-1517页

作者：苗志宏李洪兴中国人民武装警察部队学院消防工程系河北廊坊065000 大连理工大学电信学院辽宁大连116024

对于模糊控制系统稳定性问题,如何充分利用模糊规则的结构信息获得更加宽松的稳定性条件目前还没有有效的方法.本文针对T-S模糊模型利用输入空间新划分方法讨论了模糊控制系统的稳定性和控制器设计问题.首先通过输入空间新划分导出了模... 详细信息

对于模糊控制系统稳定性问题,如何充分利用模糊规则的结构信息获得更加宽松的稳定性条件目前还没有有效的方法.本文针对T-S模糊模型利用输入空间新划分方法讨论了模糊控制系统的稳定性和控制器设计问题.首先通过输入空间新划分导出了模糊规则库的一些性质.然后,通过构建一个分段可微二次Lyapunov函数,获得了保守性更低的稳定性充分条件.这一条件进一步转化成了设计模糊控制器的线性矩阵不等式条件.最后,仿真实验验证了方法的有效性.

关键词： T-S模糊模型分段二次稳定并行分布补偿方法线性矩阵不等式

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国内新型煤化工发展现状和前景分析

现代化工 2014年第8期34卷 1-5,7页

作者：李红星中国电子工程设计院北京100101

从新型煤化工发展现状、竞争力分析、发展瓶颈和发展前景等方面进行了分析,发展新型煤化工要谨慎进行。我国新型煤化工技术示范装置取得突破进展,"十二五"期间,应继续在技术、环保、节能减排等方面,开展更高水平的技术示范,有序、稳步... 详细信息

从新型煤化工发展现状、竞争力分析、发展瓶颈和发展前景等方面进行了分析,发展新型煤化工要谨慎进行。我国新型煤化工技术示范装置取得突破进展,"十二五"期间,应继续在技术、环保、节能减排等方面,开展更高水平的技术示范,有序、稳步发展新型煤化工,作为我国石化和能源的重要补充。

关键词：新型煤化工竞争力分析发展瓶颈

非线性力矩作用下气动偏心弹丸强迫圆锥运动稳定性条件

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兵工学报 2018年第5期39卷 875-882页

作者：舒敬荣李红星李宏玲安徽新华学院电子通信工程学院安徽合肥230031

为了指导无伞末敏弹等气动非对称弹丸的结构设计和气动设计,建立了气动偏心弹丸在三次方非线性静力矩和二次方非线性赤道阻尼力矩作用下的攻角方程,运用平均法求解了方程的近似解析解及其线性变分方程。在此基础上,根据Hurwitz判别准则... 详细信息

为了指导无伞末敏弹等气动非对称弹丸的结构设计和气动设计,建立了气动偏心弹丸在三次方非线性静力矩和二次方非线性赤道阻尼力矩作用下的攻角方程,运用平均法求解了方程的近似解析解及其线性变分方程。在此基础上,根据Hurwitz判别准则,得到了气动偏心弹丸做强迫圆锥运动的渐近稳定条件,分析了该条件的物理意义,并应用数值计算算例对该条件进行了验证。结果表明,当自转角速度和气动偏心角满足一定的约束条件时,三次方非线性静力矩和二次方非线性赤道阻尼力矩作用下的弹丸可以实现固定攻角的稳定强迫圆锥运动。

关键词：无伞末敏弹气动偏心非线性空气动力圆锥运动运动稳定性