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Uniaxial Compressive Property of the Lattice of Colossal Magnetoresistance Perovskite Compound La_(l-x)Sr_(x)MnO_(3)

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Chinese Physics Letters 1999年第1期16卷 38-40页

作者： ZHANG Ning DING wei-ping ZHONG wei National Laboratory of Solid State Microstructures Nanjing UniversityNanjing 210093 Department of Physics Nanjing Normal UniversityNanjing 210097

Under a uniaxial pressure of 10-20 MPa,the unusual changes of lattice parameters and remarkable structural distortions in colossal magnetoresistance perovskite La_(l-x)Sr_(x)MnO_(3)(0.15≤x≤0.25)have been *** structural distortions were found to be in good agreement with Bridgman *** phenomena suggest that the lattice of the manganese perovskite is flexible and the versatility of the electronic and magnetic properties in the perovskites may stems from the lattice flexibility.

关键词： equation. perovskite lattice

Adsorption of chloroacetanilide herbicides on soil (I) Structural influence of chloroacetanilide herbicide for their adsorption on soils and its components

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Journal of Environmental Sciences 2001年第1期13卷 37-45页

作者： LIU wei ping LIU Hui jun ZHENG wei LU Jian hang Institute of Environmental Science Zhejiang University at Yuquan CampusHangzhou 310027China.

Adsorption of chloroacetanilide herbicide acetochlor, alachlor, metolachlor and propachlor on soils and soil components was determined, and the structural differences of these herbicides were used to explain the order of sorptivity. Adsorption isotherms for all herbicide-soil combinations conformed to the Freundlich equation, and Kf increased with increasing soil organic carbon content. Kd on soil humic acid was greater than that on clay, but association of humic acid with clay reduced the overall adsorption. On all soils and soil humic acids, herbicide adsorption decreased in the order: metolachlor > acetochlor > propachlor > alachlor. On Ca2+ - montmorrilonite, the order changed to metolachlor > acetochlor > alachlor > propachlor. FT-IR spectra of herbicide-clay or herbicide-humic acid-clay mixtures showed that H-bonding and charge transfer were the primary interaction pathways between these compounds and the surface of clay or humic acids. The different moieties attached to 2-chloro-acetanilide and their unique arrangement may have influenced the binding mechanisms and thus the sorptivity of these herbicides. This study indicates that the structural difference of pesticides in the same classes may be used as a molecular probe to obtain a better understanding of sorption mechanisms of pesticides on soil.

关键词： adsorption chloroacetanilide herbicides soil organic matter clay

Methods for seismic sedimentology research on continental basins

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Petroleum Science 2015年第1期12卷 67-80页

作者： ping-Sheng wei Ming-Jun Su Petrochina Research Institute of Petroleum Exploration & Development-Northwest

In contrast to marine deposits, continental deposits in China are characterized by diverse sedimentary types, rapid changes in sedimentary facies, complex lithology, and thin, small sand bodies. In seismic sedimentology studies on continental lacustrine basins, new thinking and more detailed and effective technical means are needed to generate lithological data cubes and conduct seismic geo- morphologic analyses. Based on a series of tests and studies, this paper presents the concepts of time-equivalent seismic attributes and seismic sedimentary bodies and a ＂four-step approach＂ for the seismic sedimentologic study of conti- nental basins： Step 1, build a time-equivalent stratigraphic framework based on vertical analysis and horizontal corre- lation of lithofacies, electrofacies, seismic facies, and pale- ontological combinations; Step 2, further build a sedimentary facies model based on the analysis of single- well facies with outcrop, coring, and lab test data; Step 3, convert the seismic data into a lithological data cube reflecting different lithologies by means of seismic tech- niques; and Step 4, perform a time-equivalent attribute analysis and convert the planar attribute into a sedimentary facies map under the guidance of the sedimentary facies model. The whole process, highlighting the verification and calibration of geological data, is an iteration and feedback procedure of geoseismic data. The key technologies include the following：（1） a seismic data-lithology conversion technique applicable to complex lithology, which can convert the seismic reflection from interface types to rock layers; and （2） time-equivalent seismic unit analysis and a time- equivalent seismic attribute extraction technique. Finally, this paper demonstrates the validity of the approach with an example from the Qikou Sag in the Bohai Bay Basin and subsequent drilling results.

关键词： Continental basin Seismic sedimentology Four-step approach Time-equivalent seismic attribute Seismic sedimentary body Lithology conversion processing

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倒角对小叶高透平级性能影响的研究

汽轮机技术 2025年第1期67卷 37-41,48页

作者：陈阳丁伟平孙奇宋放放王姗东方汽轮机有限公司德阳618000 国家能源集团岳阳发电有限公司岳阳421302

以小叶高透平级为研究对象,应用全三维CFD数值模拟研究了不同倒角半径对透平级流场、效率和通流能力等方面的影响。倒角对叶型端部截面压力分布在吸力面和压力面上的主要影响区域不同,并且倒角推迟了叶片二次流的发展,但却提前并强化了... 详细信息

以小叶高透平级为研究对象,应用全三维CFD数值模拟研究了不同倒角半径对透平级流场、效率和通流能力等方面的影响。倒角对叶型端部截面压力分布在吸力面和压力面上的主要影响区域不同,并且倒角推迟了叶片二次流的发展,但却提前并强化了通道涡的发展,同时增加了叶型尾迹损失。小叶高透平级静叶和动叶的最佳倒角半径数值上约为相应叶片端部喉宽的0.22~0.25倍。提出了一种预测倒角对小叶高透平级通流能力影响的工程预估方法,应用该方法预测的透平级流量与相应数值分析结果高度吻合。

关键词：倒角小叶高透平级数值模拟气动性能流量偏差

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五味子甲素改善氧化应激引起的内皮功能障碍

中国药理学通报 2025年第1期41卷 122-130页

作者：侯惠民张文文赵卫萍赵鑫朴贤美寒地心血管疾病国家重点实验室哈尔滨医科大学药学院药理学教研室黑龙江省生物医药工程重点实验室—省部共建国家重点实验室培育基地心血管药物研究教育部重点实验室黑龙江哈尔滨150086

目的探究五味子甲素(schizandrin A,SchA)对氧化应激引起内皮功能障碍的拮抗作用及其作用机制。方法选用人脐静脉内皮细胞(human umbilical vein endothelial cells,HUVECs)作为研究对象,采用MTT实验检测SchA对HUVECs活力的影响;通过流... 详细信息

目的探究五味子甲素(schizandrin A,SchA)对氧化应激引起内皮功能障碍的拮抗作用及其作用机制。方法选用人脐静脉内皮细胞(human umbilical vein endothelial cells,HUVECs)作为研究对象,采用MTT实验检测SchA对HUVECs活力的影响;通过流式细胞技术检测细胞中ROS的含量;试剂盒检测HUVECs中MDA、CAT的含量以及细胞上清液中NO、ET-1的含量;Western blot实验检测细胞中SOD1、p-eNOS/eNOS蛋白以及Nrf2/Keap1/HO-1通路蛋白的表达情况;免疫荧光实验检测细胞Nrf2的入核情况。结果SchA通过激活Nrf2/Keap1/HO-1信号通路逆转LPS或缺氧诱导的HUVECs内ROS和MDA含量的升高及SOD1和CAT含量的下降;SchA逆转LPS诱导的HUVECs中p-eNOS和eNOS蛋白表达的降低及逆转细胞培养液中NO含量的下降和ET-1含量的升高;Nrf2抑制剂ML385逆转SchA对氧化应激及内皮功能障碍的拮抗作用。结论SchA拮抗LPS及缺氧诱导的氧化应激,SchA通过上调Nrf2/Keap1/HO-1信号通路改善氧化应激引起的内皮功能障碍。

关键词： SchA 氧化应激内皮功能障碍 Nrf2/Keap1/HO-1信号通路 HUVECs LPS

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The Einstein-Khler Metric on the Third Cartan-Hartogs Domain

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Acta Mathematica Sinica,English Series 2008年第10期24卷 1703-1712页

作者： Wen Juan ZHANG wei ping YIN Department of Mathematics Beijing Institute of Technology Beijing 100081 P. R. China Department of Mathematics Capital Normal University Beijing 100037 P. R. China

In this paper we discuss the Einstein-Kahler metric on the third Cartan-Hartogs domain Y111（n, q; K）. Firstly we get the complete Einstein Kahler metric with explicit form on Y111（n, q; K） in the case of K=q/2 ＋ 1/q-1. Secondly we obtain the holomorphic sectional curvature under this metric and get the sharp estimate for this holomorphic curvature. Finally we prove that the complete Einstein-Kahler metric is equivalent to the Bergman metric on Y111（n, q; K） in case of K=q/2＋1/q-1.

关键词： Einstein Kahler metric holomorphic sectional curvature holomorphic automorphism group

Onc*-Normal Subgroups in Finite Groups

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Acta Mathematica Sinica,English Series 2012年第3期28卷 623-630页

作者： Hua Quan wei wei ping GU Hong Fei PAN School of Mathematics Science Guangxi Teachers Education University School of Mathematics and Computer Science Xinyang Normal University

A subgroup H of a finitegroup G is called a c＊-normal subgroup of G if there exists a

关键词： c*-Normal S-quasinormally embedded p-nilpotent p-supersolvable

Hydrothermal Synthesis and Crystal Structure of a Novel Composite Keggin-type Arsenotungstate: [Ni(phen)_2][Hphen](AsW_(12)O_(40))

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Chinese Journal of Structural Chemistry 2007年第2期26卷 194-198页

作者： WANG Jing-ping WANG wei NIUJing-Yang Institute of Molecular and Crystal Engineering School of Chemistryand Chemical Engineering Henan University Kaifeng 475001 China

A novel polyoxometalate-based composite compound [Ni（phen）2][Hphen]（AsW12040）（phen = 1,10-phenanthroline） I has been hydrothermally synthesized and characterized by elemental analysis, IR, TGA, ESR spectroscopy and single-crystal X-ray diffraction. Each structure unit of 1 consists of one polyoxoanion AsW12O40^3-, one free phenanthroline molecule and one coordination cation [Ni（phen）2]^2＋. The title compound crystallizes in the orthorhombic system, space group F212121, with a = 12.2383（7）, b = 21.0884（11）, c = 22.3237（12） A, V= 5761.4（5） A^3, Mr = 3520.44, Z = 4, Dc = 4.059 g/cm^3, F（000） = 6204, g（MoKα） = 24.844 mm^-1, GOF = 1.022, the final R = 0.0376 and wR = 0.0742 （I 〉 2σ（I）） for 865 parameters and 9637 observed reflections with I 〉 2σ（I）.

关键词： polyoxotungstate hydrothermal synthesis Keggin structure ESR

Behaviors of different inhibitors during secondary recrystallization of a grain-orientated silicon steel

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International Journal of Minerals,Metallurgy and Materials 2011年第3期18卷 314-319页

作者： Feng-e Cui ping Yang wei-min Mao School of Materials Science and Engineering University of Science and Technology Beijing 100083 China

The behaviors of different inhibitors including their composition, size, distribution, coalescence and coarsening were experimen-tally studied. It was observed that during secondary recrystallization of the tested steel, the key inhibition effect was produced by Cu2S and AlN, but not MnS. With the increase of temperature, the size distributions of AlN and Cu2S were changed to some extent. However, signifi-cant changes in particle size were not observed. The initial temperature of abnormal growth was determined by measuring the evolution of particle sizes and their distribution density during heat treatment. AlN and Cu2S are the dominant inhibitors and both are necessary, which is verified by calculating the Zener factor.

关键词： silicon steel secondary recrystallization inhibitors grain growth