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湖北农业科学 2017年第21期56卷 4203-4207页

作者：柏振忠叶蓝谦宋玉娥王红玲中南民族大学经济学院武汉430074 湖北大学商学院武汉430062

选取湖北省荆州市荆楚富民农机专业合作社联合社、监利县福娃三丰农民专业合作联社、洪湖市春露农业合作社联合社等典型,分析合作联社农业共营的基本情况和成效,重点剖析农业共营中存在的突出问题,并提出相应的对策与建议。

关键词：农民专业合作联社农业共营成效

Approximation of the Shannon Capacity Via Matrix Cone Programming

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Journal of the Operations Research Society of China 2023年第4期11卷 875-889页

作者： Shi-Tong Wu zhen-Nan Zhou zhong-Yi Huang Bo bai Department of Mathematical Sciences Tsinghua UniversityBeijing100084China Theory Lab Central Research Institute2012 LabsHuawei Technologies Co.Ltd.Hong KongChina Beijing International Center for Mathematical Research Peking UniversityBeijing100871China

This paper proposes a novel formulation using the matrix cone programming to compute an upper bound of the Shannon capacity of graphs,which is theoretically superior to the Lovász *** achieve this,a sequence of matrix cones is constructed by adding certain co-positive matrices to the positive semi-definite matrix cones during the matrix cone *** require the sequence of matrix cones to have the weak product property so that the improved result of the matrix cone programming remains an upper bound of the Shannon *** result shows that the existence of a sequence of suitable matrix cones with the weak product property is equivalent to the existence of a co-positive matrix with testable ***,we give some concrete examples with special structures to verify the existence of the matrix cone sequence.

关键词： Shannon capacity Lovász number Matrix cone programming Weak product property

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高品质学校的内涵结构、建设困境与突破路径

教学与管理 2025年第1期 19-23页

作者：邓纯臻隆平陈书忠重庆师范大学生命科学学院重庆401331 四川省攀枝花市第七高级中学校四川攀枝花617005 重庆市育才中学校重庆400050

高品质学校的创建既是区域教育高质量发展的基本组成,也是助推教育强国、人才强国建设的实践基础。综合来看,学校内部维度的高品质是一种过程取向以及主观层面的高品质,外部维度的高品质是一种结果取向以及客观层面的高品质,高品质学校... 详细信息

高品质学校的创建既是区域教育高质量发展的基本组成,也是助推教育强国、人才强国建设的实践基础。综合来看,学校内部维度的高品质是一种过程取向以及主观层面的高品质,外部维度的高品质是一种结果取向以及客观层面的高品质,高品质学校包括学生、教师、管理者以及课程、课堂、课题六个核心的动力要素。当前,高品质学校的建设依然在前沿理论、本地生源、教育资源以及师资队伍等方面存在一些阻碍,对此,建议从学校文化、优质资源、课程体系、师资队伍、管评系统等五个维度探寻突破路径,以期找到高品质学校的创新之路、高品质之路。

关键词：教育高质量发展高品质学校中小学管理学校治理

高原低氧增加大鼠大脑皮层脑红蛋白的表达（英文）

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中国高原医学与生物学杂志 2017年第2期38卷 73-80页

作者：韩淑芬白振忠曹越罗朋立靳国恩杨应忠格日力青海大学医学院高原医学研究中心青海西宁810001 苏州大学公共卫生学院江苏苏州215123 青海大学附属医院青海西宁810001

目的大量研究显示脑红蛋白(neuroglobin,NGB)对缺氧缺血性脑损伤具有保护作用。本研究探讨了SD大鼠暴露于高原低压低氧后NGB的表达情况,为阐明高原低氧性脑损伤的发生机制提供了新的思路。方法 70只雄性SD大鼠按体重随机分为两组,正常... 详细信息

目的大量研究显示脑红蛋白(neuroglobin,NGB)对缺氧缺血性脑损伤具有保护作用。本研究探讨了SD大鼠暴露于高原低压低氧后NGB的表达情况,为阐明高原低氧性脑损伤的发生机制提供了新的思路。方法 70只雄性SD大鼠按体重随机分为两组,正常对照组(N=10,西宁,海拔2260米)和实验组(N=60,可可西里,海拔4600米),实验组是经西宁陆运至可可西里(海拔4600米)制作的急慢性高原缺氧模型组;依据高原暴露时间不同,将实验组又随机分为缺氧12 h组、24 h组、48 h组、72 h组、168 h组、720 h组(慢性组),每组10只。采用RT-PCR和Western blot检测高原低氧暴露不同时间脑皮质神经元中NGB mRNA和蛋白的表达含量。结果大鼠初入特高海拔地区后,Sa O2较对照组明显下降(P0.05),而后有缓慢升高趋势,至720 h(mRNA表达99.38±21.26;蛋白表达8.50±2.98)后保持一个较高水平。结论急慢性高原低氧环境下,脑红蛋白表达的增高,增强了大鼠对高原低氧的耐受性,提示NGB表达变化可能是脑组织对脑缺氧的一种内源性神经保护反应,增加了脑组织的供氧,维持了神经元的正常功能。

关键词：脑红蛋白低氧脑损伤活性氧

PROGRESS IN PHASE INVERSION EMULSIFICATION FOR EPOXY RESIN WATERBORNE DISPERSIONS

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Chinese Journal of Polymer Science 2007年第2期25卷 137-143页

作者： zhen-zhong Yang State Key Laboratory of Polymer Physics and Chemistry Institute of Chemistry Chinese Academy of Sciences Beijing 100080 China

In this review, our recent work in phase inversion emulsification （PIE） for polymer （especially epoxy resin） waterborne dispersions is summarized. Based on experimental results about PIE process, the physical model is proposed which can guide the synthesis of the waterborne dispersions such as polymer/nanoparticle composite dispersion. In the presence of a latent curing catalyst, PIE can give a crosslinkable epoxy resin waterborne dispersion. The dispersions can form cured transparent coatings with some unique properties such as UV shielding. They are promising in functional coatings, waterborne resin matrices for composites, and sizing for high performance fibers.

关键词： Phase inversion emulsification Epoxy resin Waterborne dispersions.

Conformation of 1,2-Dimethoxyethane in Water

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Chemical Research in Chinese Universities 2001年第3期17卷 315-317页

作者： LIU Yue YANG Xiao-zhen DAI bai-qing SU zhong-min WANG Qi Institute of Opto-electronics Harbin Institute of TechnologyHarbin 150001P.R.China Polymer Physics Laboratory Institute of ChemistryAcademia SinicaBeijing 100080P.R.China Department of Chemistry Harbin Normal UniversityHarbin 150080P.R.China Department of Chemistry Northeast Normal universityChangchun 130024P.R.China

To understand the conformation of 1,2-dimethoxyethane (DME) in water, a system of two kinds of molecules, DME and H_2O, was focused. The interaction of various conformers of DME with water was studied by means of ab initio molecular orbital calculation with 6-31G (d) basis set. It is shown that there are two forms of interactions between the two molecules in the system, the close touched (H_2O attaches to the two oxygen atoms of DME) and the open touched (H_2O attaches to one oxygen atom of DME) structures. The conformation of DME is remarkably influenced by the interactions. Instead the ttt conformer is preferred in the gas state, with a close touched H_2O the tgt conformer becomes the most stable one. The obtained hydration energies show that the stabilized order of DME conformers by water is tgt>tgg′>ttt.

关键词： 1 2-Dimethoxyethane Conformation Ab initio Molecular orbital calculation

Analysis of finite-time practical stability for time-varying polytopic systems

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Journal of Systems Engineering and Electronics 2009年第1期20卷 112-119页

作者： zhong zhen Duan Guangren Harbin Inst. of Technology Harbin 150001 P. R. China

The problem of finite-time practical stability （FTPS） for time-varying polytopic systems is discussed. Three equivalent conditions for FTPS are first proposed. To facilitate the system analysis, a sufficient linear matrix inequality （LMI） criterion on the FTPS is further provided. The definition of finite-time practical boundedness and a sufficient LMI criterion are also provided to overcome the exogenous disturbance. A numerical example is used to illustrate the effect of the proposed approach.

关键词： polytopic systems linear matrix inequality finite-time control practical stability.

Six-DOF trajectory optimization for reusable launch vehicles via Gauss pseudospectral method

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Journal of Systems Engineering and Electronics 2016年第2期27卷 434-441页

作者： zhen Wang zhong Wu School of Instrumentation Science and Optoelectronics Engineering Beihang UniversityBeijing 100191China China Institute of Marine Technology&Economy Beijing 100081China

To be close to the practical flight process and increase the precision of optimal trajectory, a six-degree-offreedom（6-DOF） trajectory is optimized for the reusable launch vehicle（RLV） using the Gauss pseudospectral method（GPM）. Different from the traditional trajectory optimization problem which generally considers the RLV as a point mass, the coupling between translational dynamics and rotational dynamics is taken into account. An optimization problem is formulated to minimize a performance index subject to 6-DOF equations of motion, including translational and rotational dynamics. A two-step optimal strategy is then introduced to reduce the large calculations caused by multiple variables and convergence confinement in 6-DOF trajectory optimization. The simulation results demonstrate that the 6-DOF trajectory optimal strategy for RLV is feasible.

关键词： reusable launch vehicle(RLV) trajectory optimization Gauss pseudospectral method(GPM)

ON HERMITIAN AND SKEW-HERMITIAN SPLITTING ITERATION METHODS FOR CONTINUOUS SYLVESTER EQUATIONS

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Journal of Computational Mathematics 2011年第2期29卷 185-198页

作者： zhong-Zhi bai LSEC ICMSEC Academy of Mathematics and Systems Science Chinese Academy of Sciences Beijing 100190 China

We present a Hermitian and skew-Herrnitian splitting （HSS） iteration method for solving large sparse continuous Sylvester equations with non-Hermitian and positive definite/semi- definite matrices. The unconditional convergence of the HSS iteration method is proved and an upper bound on the convergence rate is derived. Moreover, to reduce the computing cost, we establish an inexact variant of the HSS iteration method and analyze its convergence property in detail. Numerical results show that the HSS iteration method and its inexact variant are efficient and robust solvers for this class of continuous Sylvester equations.

关键词： Continuous Sylvester equation HSS iteration method Inexact iteration Convergence.

铅和乙醇联合作用对雄性大鼠生殖内分泌的影响

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山东医科大学学报 2001年第2期39卷 184-186页

作者：于素芳白忠贞赵敬杰崔晞童振山东大学公共卫生学院劳动卫生学教研室山东大学第二医院核医学室山东大学公共卫生学院卫生化学教研室

目的 :探讨铅和乙醇联合作用对雄性大鼠生殖内分泌的影响。方法 :雄性大白鼠 54只 ,体重(2 0 7± 17) g ,采用 2× 3析因设计方法随机分为 9组 ,每组 6只 ,1次 /d灌胃 ,5次 /周 ,连续 4周 ,染毒期满断头处死 ,取血做T、FSH、LH及血铅的... 详细信息

目的 :探讨铅和乙醇联合作用对雄性大鼠生殖内分泌的影响。方法 :雄性大白鼠 54只 ,体重(2 0 7± 17) g ,采用 2× 3析因设计方法随机分为 9组 ,每组 6只 ,1次 /d灌胃 ,5次 /周 ,连续 4周 ,染毒期满断头处死 ,取血做T、FSH、LH及血铅的分析。结果 :染毒组与对照组比较 ,T值降低 ,FSH、LH、血铅增高 (P <0 .0 1) ,联合染毒组与各单独染毒组 (除B组T值 )比较差异有显著性 (P <0 .0 1、P <0 .0 5) ;铅、乙醇及二者联合分别对 3项内分泌指标及血铅的影响有显著性意义 (P <0 .0 1、P <0 .0 5) ;逐步回归显示血铅与FSH、LH呈正相关关系 ,与T呈负相关。结论 :铅和乙醇联合作用对雄性大鼠生殖内分泌激素T、FSH和LH水平变化有明显的增毒作用。

关键词：铅乙醇雄性大鼠生殖内分泌