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永磁铁磁贴合体的磁场及磁力

电工技术学报 2008年第6期23卷 7-13页

作者：田录林贾嵘杨国清田琦李知航李辉西安理工大学水电学院西安710048 西北大学数学系西安710069 西安电子科技大学通讯工程学院西安710071

为了寻求永磁铁磁贴合体磁场及磁力的简便算法,基于介质分界面为平面的电流镜像法及永磁体等效电流模型,把铁磁体被磁化的效果视为铁磁体内某处存在"虚设"磁体产生的磁场,得到了永磁体在平面铁磁体中的镜像规律,给出了永磁体为圆柱体及... 详细信息

为了寻求永磁铁磁贴合体磁场及磁力的简便算法,基于介质分界面为平面的电流镜像法及永磁体等效电流模型,把铁磁体被磁化的效果视为铁磁体内某处存在"虚设"磁体产生的磁场,得到了永磁体在平面铁磁体中的镜像规律,给出了永磁体为圆柱体及长方体的一个永磁铁磁贴合体和一对平行吸力型永磁铁磁贴合体在轴线空间的磁感应强度解析公式,并对与平面铁磁体贴合的一对永磁环及永磁铁磁导轨磁力计算值作了试验验证。结果表明计算值和实验值基本吻合,用本文永磁体镜像规律及磁场解析公式计算永磁铁磁贴合体的磁场及磁力不仅简单而且计算精度较高。

关键词：永磁体等效模型永磁体镜像磁场磁力数学模型

A FACILE SYNTHESIS OF 2-TRIFLUOROMETHYLPYRROLE VIA 1,3-DIPOLAR CYCLOADDITION REACTION OF 2-TRIFLUOROMETHYLOXAZOLONE AND THE ACTIVATED CARBON-CARBON MULTIPLE BOND

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Chinese Chemical Letters 1991年第3期2卷 217-220页

作者： Wei Sheng tian Yu Qun Chen Yong rong Luo Xiao Wen Deng Shanghai Institute of Organic Chemistry,Academia Sinica,345 Lingling Lu,Shanghai 200032

The 1.3-dipolar cycloaddition reaction of 2-trifluoromethyl- oxazolone and the activated carbon-carbon multiple bond was studied and gave a convenient way to synthesize 2-trifluoromethylpyrrole derivatives.

关键词： Cl A FACILE SYNTHESIS OF 2-TRIFLUOROMETHYLPYRROLE VIA 1,3-DIPOLAR CYCLOADDITION REACTION OF 2-TRIFLUOROMETHYLOXAZOLONE AND THE ACTIVATED CARBON-CARBON MULTIPLE BOND ppm VIA

THE FLOW ANALYSIS OF FLUIDS IN FRACTAL RESERVOIR WITH THE FRACTIONAL DERIVATIVE

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Journal of Hydrodynamics 2006年第3期18卷 287-293页

作者： tian Ji TONG Deng-ke Institute of Mechanics Chinese Academy of ScienceBeijing 100080China Gudong Petroleum Factory of Shengli Petroleum Administration Dongying 256504China Departmentof Applied Mathematics China University of Petroleum Dongying 257061 China

In this paper, fractional order derivative, fractal dimension and spectral dimension are introduced into the seepage flow mechanics to establish the flow models of fluids in fractal reservoirs with the fractional derivative. The flow characteristics of fluids through a fractal reservoir with the fractional order derivative are studied by using the finite integral transform, the discrete Laplace transform of sequential fractional derivatives and the generalized Mittag-Leffler function. Exact solutions are obtained for arbitrary fractional order derivative. The long-time and short-time asymptotic solutions for an infinite formation are also obtained. The pressure transient behavior of fluids flow through an infinite fractal reservoir is studied by using the Stehfest＇s inversion method of the numerical Laplace transform. It shows that the order of the fractional derivative affect the whole pressure behavior, particularly, the effect of pressure behavior of the early-time stage is larger The new type flow model of fluid in fractal reservoir with fractional derivative is provided a new mathematical model for studying the seepage mechanics of fluid in fractal porous media.

关键词： fractional calculus porous media fractal,integral transform exact solution

纳米TiO_2/MnO_2修饰ACF电极及其催化降解染料废水

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功能材料 2014年第6期45卷 55-59页

作者：杨志清文晨田荣敏天津工业大学环境与化学工程学院天津300387 天津工业大学中空纤维膜材料与膜过程省部共建国家重点实验室培育基地天津300387

通过调节水热工艺制备了两种纳米TiO2和MnO2氧化物,采用涂覆法得到了3种修饰活性炭纤维(ACF)电极,并借助透射电镜(TEM)和循环伏安法(CV)等手段对TiO2和MnO2的形貌与尺寸,修饰ACF电极的电化学性能等进行了表征。结果表明,TiO2和MnO2均为... 详细信息

通过调节水热工艺制备了两种纳米TiO2和MnO2氧化物,采用涂覆法得到了3种修饰活性炭纤维(ACF)电极,并借助透射电镜(TEM)和循环伏安法(CV)等手段对TiO2和MnO2的形貌与尺寸,修饰ACF电极的电化学性能等进行了表征。结果表明,TiO2和MnO2均为一维纳米结构,其中TiO2为棒状,MnO2属管态;在电极体系中,由TiO2和MnO2修饰的二元ACF电极凸显了较高的导电性,其电流密度的顺序依次是ACF

关键词：水热法 -维结构修饰炭电极高盐染料废水 COD去除率

Partitioning Planar Graphs with Girth at Least 6 into Bounded Size Components

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Journal of Mathematical Research with Applications 2023年第1期43卷 16-24页

作者： Chunyu tian Lei SUN School of Mathematics and Statistics Shandong Normal University

An(Ok1、Ok2)-partition of a graph G is the partition of V（G） into two non-empty subsets V1and V2,such that G[V1] and G[V2] are graphs with components of order at most k1and k2,*** this paper,we consider the problem of partitioning the vertex set of a planar graph with girth restriction such that each part induces a graph with components of bounded *** prove that every planar graph with girth at least 6 and i-cycle is not intersecting with j-cycle admits an（O2,O3）-partition,where i∈{6,7,8} and j∈{6,7,8,9}.

关键词： planar graph face girth vertex partition discharging procedure

Hyperbaric Oxygen and Ginkgo Biloba Extract Ameliorate Cognitive and Memory Impairment via Nuclear Factor Kappa-B Pathway in Rat Model of Alzheimer＇s Disease

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Chinese Medical Journal 2015年第22期128卷 3088-3093页

作者： Li-da Zhang Li Ma Li Zhang Jian-Guo dai Li-Gong Chang Pei-Lin Huang Xiao-Qiang tian Department of Hyperbaric Oxygen Affiliated ZhongDa Hospital of Southeast University Nanjing Jiangsu 210009 China Department of Neurology Brain Hospital Affiliated of Nanjing Medical University Nanjing Jiangsu 210029 China Department of Pathology Nanjing University of Traditional Chinese Medicine Nanjing Jiangsu 210023 China Department of Pathology Medicine School of Southeast University Nanjing Jiangsu 210009 China Medical Oncology The Second Hospital of Nanjing Affiliated to Medical School of Southeast University Nanjing Jiangsu 210003 China

Background： Hyperbaric oxygen （HBO） and Ginkgo biloba extract （e.g., EGB 761） were shown to ameliorate cognitive and memory impairment in Alzheimcr＇s disease （AD）. However, the exact mechanism remains elusive. The aim of the present study was to investigate the possible mechanisms of HBO and EGB 761 via the function of nuclear factor kappa-B （NF-κB） pathway. Methods： AD rats were induced by injecting β-amyloid 25-35 into the hippocampus. All animals were divided into six groups： Normal. sham. AD model, HBO （2 atmosphere absolute： 60 min/d）, EGB 761 （20 mg·kg^-1 ·d ^-1）, and HBO/EGB 761 groups. Morris water maze tests were used to assess cognitive, and memory capacities of rats： TdT-mediated dUTP Nick-End Labeling staining and Western blotting were used to analyze apoptosis and NF-κB pathway-related proteins in hippocampus tissues. Results： Morris water maze tests revealed that EGB 761 and HBO significantly improved the cognitive and memory ability of AD rats. In addition, the protective effect of combinational therapy （HBO/EGB 761 ） was superior to either HBO or EGB 761 alone. In line. redticed apoptosis with NF-κB pathway activation was observed in hippocampus neurons treated by HBO and EGB 761. Conclusions： Our results suggested that HBO and EGB 761 improve cognitive and memory capacity in a rat model of AD. The protective effects are associated with the reduced apoptosis with NF-κB pathway activation in hippocampus neurons.

关键词： Ginkgo Biloba Extract 761 Hyperbaric Oxygen Nuclear Factor Kappa-B Rats Alzheimer's Disease

Mental health and preventive behaviour of pregnant women in China during the early phase of the COVID-19 period

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Infectious Diseases of Poverty 2021年第2期10卷 80-81页

作者： Qian Wang Phoenix K.H.Mo Bo Song Jiang-Li Di Feng-rong Zhou Juan Zhao Ying-Lan Wu Hong tian Li-Qian Qiu Jianhong Xia Lan Wang Fen Li Lin-Hong Wang National Center for Chronic and Noncom municable Disease Control and Prevention Chinese Center for Disease Control and Prevention13#Rd NanweiXichengBeijingChina 不详

Background:The COVID-19 has caused significant toll over the *** women are at risk of *** present study examined the frequency of washing hands with soap and wearing face mask when going out,prevalence of depression and anxiety,and identified their associated factors among pregnant women during the early phase of COVID-19 outbreak in China.

关键词： COVID-19 Personal preventive behaviour Depression Anxiety Mental health Pregnant women China

Large-scale synthesis of carbon nanospheres by catalyzed pyrolysis of tree leaves

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材料科学与工程（中英文版） 2009年第3期3卷 25-30页

作者： WANG Xian-bao LI Ming-jian LIU Fang-ming ZHENG Han HU Hua-ting CHEN rong WAN Li LI Shao-qing tian rong Ministry-of-Education Key Laboratory for the Green Preparation and Application of Functional Materials Wuhan 430062 China Faculty of Materials Science and Engineering Hubei University Wuhan 430062 China

基于M算法的1000 BASE-T千兆以太网收发器联合解码均衡器实现研究

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上海交通大学学报 2007年第8期41卷 1358-1361,1365页

作者：诸悦戎蒙恬毛军发上海交通大学电子信息与电气工程学院上海200240

提出了一类适用于IEEE 802.3ab标准1000 BASE-T千兆以太网收发器的预滤波M算法联合解码均衡器.通过研究保留路径数、期望信道响应拖尾长度以及回溯深度等参数对M算法解码器的性能与硬件复杂度的影响,确定了优化参数和结构.0.18μm标准单... 详细信息

提出了一类适用于IEEE 802.3ab标准1000 BASE-T千兆以太网收发器的预滤波M算法联合解码均衡器.通过研究保留路径数、期望信道响应拖尾长度以及回溯深度等参数对M算法解码器的性能与硬件复杂度的影响,确定了优化参数和结构.0.18μm标准单元CMOS工艺下的综合和后仿真证明其性能与硬件复杂度均优于常用的预滤波并行判决反馈解码器(Parallel Deci-sion Feedback Decoder,PDFD).研究表明,预滤波M算法解码器适合在多种情况下取代预滤波PDFD,用于1000 BASE-T千兆以太网收发器联合解码均衡器,其中4tap PF-MA4解码器的性能优于14tap PDFD,而面积仅为其39%.

关键词： 1000 BASE—T 千兆以太网 M算法并行判决反馈解码器