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Viability for a class of semilinear differential equations of retarded type

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Applied Mathematics(A Journal of Chinese Universities) 2009年第1期24卷 36-44页

作者： DONG Qi-xiang LI Gang School of Math. Sci., yangzhou Univ., yangzhou 225002, China School of Math. Sci. Yangzhou Univ. Yangzhou 225002 China

Let X be a Banach space, A ： D（A） X → X the generator of a compact C0- semigroup S（t）： X → X, t ≥ 0, D a locally closed subset in X, and f ：（a, b） × X →X a function of Caratheodory type. The main result of this paper is that a necessary and sufficient condition in order to make D a viable domain of the semilinear differential equation of retarded type u＇（t） = Au（t）＋ f（t, u（t - q））, t ∈ [to, to ＋ T], with initial condition uto = φ ∈C（[-q, 0]; X）, is the tangency condition lim infh10 h^-1d（S（h）v（O）＋hf（t, v（-q））; D） = 0 for almost every t ∈ （a, b） and every v ∈ C（[-q, 0]; X） with v（0）, v（-q）∈ D.

关键词： viability differential equation retarded type tangency condition

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公主岭霉素在水稻育秧期应用技术研究

东北农业科学 2019年第2期44卷 28-33页

作者：安俊霞李晓光汪洋洲张正坤马嵩岳张静杨会营文松杜茜李启云吉林农业大学植物保护学院长春130118 吉林省农业科学院/吉林省农业微生物重点实验室长春130033 通化市农业科学研究院吉林海龙135007 燕化永乐(乐亭)生物科技有限公司河北乐亭063600

研究了公主岭霉素对水稻发芽率和幼苗建成主要生长指标的影响及其不同施药方式下公主岭霉素在室内模拟条件中水稻育秧期生长指标的差异,初步确定了不同施药方式的最佳施药量,并在实际生产中从幼苗长势和苗期主要病害发生状况两方面综合... 详细信息

研究了公主岭霉素对水稻发芽率和幼苗建成主要生长指标的影响及其不同施药方式下公主岭霉素在室内模拟条件中水稻育秧期生长指标的差异,初步确定了不同施药方式的最佳施药量,并在实际生产中从幼苗长势和苗期主要病害发生状况两方面综合考虑,探讨了公主岭霉素在水稻育秧期应用的可行性。实验结果表明,公主岭霉素在水稻育秧期施用,对水稻幼苗建成的影响主要表现在促进种子发芽率和幼苗株高的提升上,对根的伸长略表现出抑制作用,对苗鲜重和根鲜重影响不显著,其中对于株高的影响以2000倍稀释液作用效果最为显著,比清水对照提高26.09%,比芸苔素内酯1000倍稀释液提高17.57%;比较公主岭霉素浸种、喷施和拌土三种不同施药方式,公主岭霉素最适施药量略有不同,公主岭霉素拌土最适比例为1∶1000~1∶1500,浸种最适浓度为500倍稀释液,播种后喷雾浇灌最适浓度为2000倍稀释液。大棚生产性育秧公主岭霉素最适施药浓度较实验室模拟条件略高。公主岭霉素在水稻育秧期施用对于苗期恶苗病具有一定的防治效果,本研究中对恶苗病的防效最高为65.50%。

关键词：公主岭霉素水稻幼苗建成秧苗生长恶苗病立枯病

A New Reagent for the Reduction of Aromatic Nitro Compounds

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Chinese Chemical Letters 1997年第8期8卷 683-684页

作者： Jian Guo SHAO Long Cheng wang Ming ZHENG Qi ZHONG(Medical and Pharmaceutical Research Centre, Chemistry Department of Teachers College, yangzhou University, yangzhou, 225002) yangzhou UNIV COLL TEACHERSDEPT CHEMMED & PHARMACEUT RES CTRYANGZHOU 225002PEOPLES R CHINA

Aromatic nitro compounds were reduced to the corresponding anilines by refluxing with potassium selenated borohydride (KBH2Se3) prepared from potassium borohydride and selenium in refluxed formamide.

关键词： A New Reagent for the Reduction of Aromatic Nitro Compounds

The Analysis of the Dynamic Equilibrium State in Linear Control System

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武汉理工大学学报 2006年第S3期28卷 1059-1063页

作者： wang Li Dept.of Electrical and Automation,yangzhou University,yangzhou 225009,China, Dept.of Electrical and Automation Yangzhou UniversityYangzhou 225009China

This paper discusses not a point of equilibrium to free system,but a certain family of equilibrium state of dynami- cal system with *** equilibrium state depends on the input,so it is called the dynamic equilibrium *** expression of the dynamic equilibrium state can be given under some certain *** deductions and proofs in linear control system,es- tablish the expression of the dynamic equilibrium state in two cases,where the linear systems are nonsingular or *** pre- sent the concept and the condition of the controllability of the dynamic equilibrium *** controllability of the dynamic equilib- rium state is different from the controllability of the state to system,but these two are closely related.

关键词： linear system input dynamic equilibrium state controllability

杀虫真菌在玉米内的定殖及公主岭霉素对其定殖率影响的研究

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东北农业科学 2023年第2期48卷 95-98页

作者：张云月周艳宏杜茜毛刚高月波王立辉汪洋洲吉林省农业科学院植物保护研究所吉林公主岭136100 哈尔滨师范大学哈尔滨150025 镇赉县农业技术推广中心吉林白城137300

为明确球孢白僵菌和金龟子绿僵菌在玉米植株内的定殖能力及公主岭霉素对其定殖率的影响,本研究以玉米秸秆颗粒为载体制备成载菌颗粒剂,将球孢白僵菌(Beauveria bassiana)(Bb)、金龟子绿僵菌(Metarhizium anisopliae)(Ma)和公主岭霉素(7... 详细信息

为明确球孢白僵菌和金龟子绿僵菌在玉米植株内的定殖能力及公主岭霉素对其定殖率的影响,本研究以玉米秸秆颗粒为载体制备成载菌颗粒剂,将球孢白僵菌(Beauveria bassiana)(Bb)、金龟子绿僵菌(Metarhizium anisopliae)(Ma)和公主岭霉素(769)混合接种玉米植株,使球孢白僵菌和金龟子绿僵菌在玉米内定殖。结果表明:球孢白僵菌和金龟子绿僵菌联合接种组中两种虫生真菌的定殖率分别为47.5%和78%,均高于其他处理组,定殖能力最强。三种微生物农药联合接种组球孢白僵菌和金龟子绿僵菌的定殖率最低,分别为25%和50%。结果证明,球孢白僵菌和金龟子绿僵菌联用可相互促进彼此在寄主植物中的定殖能力,公主岭霉素能抑制球孢白僵菌和金龟子绿僵菌的增效作用,但与单一菌种接种时对寄主的定殖能力影响不显著。

关键词：球孢白僵菌金龟子绿僵菌公主岭霉素定殖

BASIC FLOW PATTERNS AND OPTIMUM HYDRAULIC DESIGN OF A SUCTION BOX OF PUMPING STATION

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Journal of Hydrodynamics 2000年第4期12卷 46-51页

作者： Lu Lin guang yangzhou University, yangzhou 225009, P.R.China (Received April 14, 2000) yangzhou Univ. Yangzhou 225009 China

A numerical method based on 3 D turbulence flow was applied to simulate the flow pattern in suction boxes of six different types. In light of the computational results, the basic flow patterns in the boxes were revealed and a theoretical method to optimize hydraulically design of the suction box is developed. The box geometrical parameters, which influence the flow pattern in the box, could be optimized. The optimum criteria for the hydraulic design of the suction boxes of six types established, respectively. Furthermore, a summarization is given here based on the classification of the basic flow patterns in order to systematically understand the hydraulic design of suction boxes.

关键词： flow pattern optimum design suction box pumping station

Enhanced stability and electrochemical properties of lanthanum and cerium co-modified LiVOPO_(4) cathode materials for Li-ion batteries

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Journal of Rare Earths 2023年第10期41卷 1590-1596,I0005页

作者： Zishan Ahsan Zhenfei Cai Shuai wang Haichuan wang yangzhou Ma Guangsheng Song Shihong Zhang Weidong Yang Muhammad Imran Cuie Wen Key Laboratory of Green Fabrication and Surface Technology of Advanced Metal Materials Ministry of EducationSchool of Materials Science and EngineeringAnhui University of TechnologyMaanshan243000China School of Metallurgical Engineering Anhui University of TechnologyMaanshan243002China Future Manufacturing Flagship Commonwealth Scientific and Industry Research OrganizationMelbourneVictoria3168Australia Department of Chemistry Faculty of ScienceKing Khalid UniversityAbha61413Saudi Arabia School of Engineering RMIT UniversityBundooraVictoria3083Australia

A facile and efficient ball-milling assisted sol-gel synthesis route was developed to prepare triclinic e-LiVOPO_(4)(LVOP)material with lanthanum(La)and cerium(Ce)modification individually as well as *** LVOP/LaPO_(4)/CePO_(4)composite cathode material was successfully synthesized and results show that La and Ce co-modification noticeably improves the electrochemical performance by enhancing the high voltage capacity upon cycling,which indicates contributions from the good ionic conductors LaPO_(4)and CePO_(4).The simultaneous La and Ce modification improves the high voltage performance significantly with an increase of 50%in high voltage capacity after 20 cycles compared to pure *** also shows stabilized cycling perfo rmance with 91%capacity rete ntion after 50 cycles at 0.1 C rate,along with high-rate capability with a capacity of 83.1 mAh/g compared to the pristine sample showing the capacity of 51.6 mAh/g at a high rate of *** can be attributed to the good conductivity of LaPO_(4)and CePO_(4).In addition,the LVOP/LaPO_(4)/CePO_(4)composite and the pristine LVOP give a charge transfer resistance of-105 and-212Ω,respectively,showing much lower impedance due to a combination of La and Ce addition.

关键词： Li-ion bateries ε-LiVOP04 Cathode materials La Ce co-modification Enhanced stability Rare earths

SHORT FATIGUE CRACK PARAMETER BASED ON THE TOTAL CRACK AREA

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Acta Metallurgica Sinica(English Letters) 2001年第4期14卷 235-240页

作者： Z.X. Wu and X. C. Wu Engineering College, yangzhou University, yangzhou 225009, China Eng. Coll. Yangzhou Univ. Yangzhou 225009 China

The progressive fatigue damage of a material is closely related to the whole population of cracks on its surface. In order to understand which parameter is a more useful indicator of fatigue damage, rotatory bending fatigue tests were carried out using smooth specimens of medium-carbon steel. The behavior of short crack propagation during fatigue was examined and a new parameter total crack area was suggested. The aim of this paper is to extend the research on fatigue damage in the already studied steel and to study how these damage parameters are correlated with the process of fatigue damage in order to evaluate the effectiveness of damage detection methods.

关键词： Bending strength Crack initiation Crack propagation Fatigue testing Parameter estimation

A novel four-component reaction involving ring-opening/recyclization of 1,3-thiazolidinedione

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Science China Chemistry 2010年第4期53卷 863-868页

作者： SUN Jing, XIA ErYan, ZHANG LiLi & YAN ChaoGuo College of Chemistry & Chemical Engineering, yangzhou University, yangzhou 225002, China 1. College of Chemistry & Chemical Engineering Yangzhou University Yangzhou 225002 China

The multicomponent reactions of 1,3-thiazolidinedione, malononitrile, aromatic aldehydes and α-phenylethylamine or β-phenylethylamine in acetonitrile at room temperature produce dihydrothiophene ureidoformamide derivatives in moderate yields through a domino ring-opening/recyclization reaction of 1,3-thiazolidinedione. On treatment with DDQ, dihydrothiophenes are dehydrogenated to convert efficiently to thiophenes in the mild condition.

关键词： multicomponent reaction ring-opening recyclization dihydrothiophene thiazolidinedione