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Lie Symmetries and Conserved Quantities of Systems of Relative Motion Dynamics
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作者 刘荣万 傅景礼 梅凤翔 《Journal of Beijing Institute of Technology》 EI CAS 1998年第3期221-225,共5页
Aim To study the Lie symmetries and conserved quantities of the dynamical equationsof relative motion for holonomic mechanical systems. Methods Lie's method of the invariance of ordinary differential equations u... Aim To study the Lie symmetries and conserved quantities of the dynamical equationsof relative motion for holonomic mechanical systems. Methods Lie's method of the invariance of ordinary differential equations under infinitesimal transformations was used. Results and Conclusion The determining equaiton of the Lie symmetries for the dynamical equationS of relative motion is established.The structure quation and the form conserved quantities are obtained. An example iD illustrate the application of the result is given. 展开更多
关键词 analytical mechanics dynamical of relative motion Lie symmetry conserved quantity
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Conformal invariance and conserved quantities of dynamical system of relative motion 被引量:7
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作者 陈向炜 赵永红 李彦敏 《Chinese Physics B》 SCIE EI CAS CSCD 2009年第8期3139-3144,共6页
This paper discusses in detail the conformal invariance by infinitesimal transformations of a dynamical system of relative motion. The necessary and sufficient conditions of conformal invariance and Lie symmetry are g... This paper discusses in detail the conformal invariance by infinitesimal transformations of a dynamical system of relative motion. The necessary and sufficient conditions of conformal invariance and Lie symmetry are given simultaneously by the action of infinitesimal transformations. Then it obtains the conserved quantities of conformal invariance by the infinitesimal transformations. Finally an example is given to illustrate the application of the results. 展开更多
关键词 dynamical system of relative motion infinitesimal transformation conformal invariance conserved quantities
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Lie symmetry and the generalized Hojman conserved quantity of Nielsen equations for a variable mass holonomic system of relative motion 被引量:5
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作者 张美玲 孙现亭 +2 位作者 王肖肖 解银丽 贾利群 《Chinese Physics B》 SCIE EI CAS CSCD 2011年第11期19-22,共4页
Lie symmetry and the generalized Hojman conserved quantity of Nielsen equations for a variable mass holonomic system of relative motion are studied. The determining equation of Lie symmetry of Nielsen equations for a ... Lie symmetry and the generalized Hojman conserved quantity of Nielsen equations for a variable mass holonomic system of relative motion are studied. The determining equation of Lie symmetry of Nielsen equations for a variable mass holonomic system of relative motion under the infinitesimal transformations of groups is given. The expression of generalized Hojman conserved quantity deduced directly from Lie symmetry for a variable mass holonomic system of relative motion is obtained. An example is given to illustrate the application of the results. 展开更多
关键词 variable mass relative motion Lie symmetry generalized Hojman conserved quantity
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Mei symmetry and Mei conserved quantity of Appell equations for a variable mass holonomic system of relative motion 被引量:3
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作者 张美玲 王肖肖 +1 位作者 韩月林 贾利群 《Chinese Physics B》 SCIE EI CAS CSCD 2012年第10期17-21,共5页
Mei symmetry and Mei conserved quantity of Appell equations for a variable mass holonomic system of relative motion are studied.The definition and criterion of the Mei symmetry of Appell equations for a variable mass ... Mei symmetry and Mei conserved quantity of Appell equations for a variable mass holonomic system of relative motion are studied.The definition and criterion of the Mei symmetry of Appell equations for a variable mass holonomic system of relative motion under the infinitesimal transformations of groups are given.The structural equation of Mei symmetry of Appell equations and the expression of Mei conserved quantity deduced directly from Mei symmetry for a variable mass holonomic system of relative motion are gained.Finally,an example is given to illustrate the application of the results. 展开更多
关键词 variable mass relative motion Appell equations Mei conserved quantity
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Lie symmetry and Hojman conserved quantity of a Nielsen equation in a dynamical system of relative motion with Chetaev-type nonholonomic constraint 被引量:2
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作者 王肖肖 孙现亭 +2 位作者 张美玲 解银丽 贾利群 《Chinese Physics B》 SCIE EI CAS CSCD 2011年第12期259-263,共5页
The Lie symmetry and Hojman conserved quantity of Nielsen equations in a dynamical system of relative motion with nonholonomic constraint of the Chetaev type are studied. The differential equations of motion of the Ni... The Lie symmetry and Hojman conserved quantity of Nielsen equations in a dynamical system of relative motion with nonholonomic constraint of the Chetaev type are studied. The differential equations of motion of the Nielsen equation for the system, the definition and the criterion of Lie symmetry, and the expression of the Hojman conserved quantity deduced directly from the Lie symmetry for the system are obtained. An example is given to illustrate the application of the results. 展开更多
关键词 nonholonomic constraint of Chetaev's type relative motion Nielsen equation Hojman conserved quantity
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Noether Symmetry and Noether Conserved Quantity of Nielsen Equation for Dynamical Systems of Relative Motion 被引量:1
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作者 解银丽 杨新芳 贾利群 《Communications in Theoretical Physics》 SCIE CAS CSCD 2011年第1期111-114,共4页
Noether symmetry of Nielsen equation and Noether conserved quantity deduced directly from Noether symmetry for dynamical systems of the relative motion are studied. The definition and criteria of Noether symmetry of a... Noether symmetry of Nielsen equation and Noether conserved quantity deduced directly from Noether symmetry for dynamical systems of the relative motion are studied. The definition and criteria of Noether symmetry of a Nielsen equation under the infinitesimal transformations of groups are given. Expression of Noether conserved quantity deduced directly from Noether symmetry of Nielsen equation for the system are obtained. Finally, an example is given to illustrate the application of the results. 展开更多
关键词 dynamics of the relative motion Nielsen equations Noether symmetry Noether conserved quantity
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Mei symmetry and Mei conserved quantity of the Appell equation in a dynamical system of relative motion with non-Chetaev nonholonomic constraints 被引量:1
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作者 王肖肖 孙现亭 +2 位作者 张美玲 韩月林 贾利群 《Chinese Physics B》 SCIE EI CAS CSCD 2012年第5期6-10,共5页
The Mei symmetry and the Mei conserved quantity of Appell equations in a dynamical system of relative motion with non-Chetaev nonholonomic constraints are studied.The differential equations of motion of the Appell equ... The Mei symmetry and the Mei conserved quantity of Appell equations in a dynamical system of relative motion with non-Chetaev nonholonomic constraints are studied.The differential equations of motion of the Appell equation for the system,the definition and the criterion of the Mei symmetry,and the expression of the Mei conserved quantity deduced directly from the Mei symmetry for the system are obtained.An example is given to illustrate the application of the results. 展开更多
关键词 non-Chetaev nonholonomic constrained system dynamics of relative motion Appell equation Mei conserved quantity
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Lie-Form Invariance of the Nonholonomic System of Relative Motion in Event Space
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作者 HOU Qi-Bao LI Yuan-Cheng WANG Jing XIA Li-Li 《Communications in Theoretical Physics》 SCIE CAS CSCD 2007年第5X期795-798,共4页
In this paper, the Lie-form invariance of a nonholonomic system of relative motion in event space is studied. Firstly, the definition and the criterion of the Lie-form invariance of the nonholonomic system of relative... In this paper, the Lie-form invariance of a nonholonomic system of relative motion in event space is studied. Firstly, the definition and the criterion of the Lie-form invariance of the nonholonomic system of relative motion in event space is given. Secondly, the Hojman conserved quantity and a new type of conserved quantity deduced from the Lie-form invariance are obtained. An example is given to illustrate the application of the results. 展开更多
关键词 event space nonholonomic system relative motion Lie-form invariance conserved quantity
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Qualia Role-Based Quantity Relation Extraction for Solving Algebra Story Problems
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作者 Bin He Hao Meng +2 位作者 Zhejin Zhang Rui Liu Ting Zhang 《Computer Modeling in Engineering & Sciences》 SCIE EI 2023年第7期403-419,共17页
A qualia role-based entity-dependency graph(EDG)is proposed to represent and extract quantity relations for solving algebra story problems stated in Chinese.Traditional neural solvers use end-to-end models to translat... A qualia role-based entity-dependency graph(EDG)is proposed to represent and extract quantity relations for solving algebra story problems stated in Chinese.Traditional neural solvers use end-to-end models to translate problem texts into math expressions,which lack quantity relation acquisition in sophisticated scenarios.To address the problem,the proposed method leverages EDG to represent quantity relations hidden in qualia roles of math objects.Algorithms were designed for EDG generation and quantity relation extraction for solving algebra story problems.Experimental result shows that the proposedmethod achieved an average accuracy of 82.2%on quantity relation extraction compared to 74.5%of baseline method.Another prompt learning result shows a 5%increase obtained in problem solving by injecting the extracted quantity relations into the baseline neural solvers. 展开更多
关键词 quantity relation extraction algebra story problem solving qualia role entity dependency graph
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Optimization of cutting parameters with Taguchi and grey relational analysis methods in MQL-assisted face milling of AISI O2 steel 被引量:4
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作者 Bilal KURSUNCU Yasin Ensar BIYIK 《Journal of Central South University》 SCIE EI CAS CSCD 2021年第1期112-125,共14页
This study aims to examine the usability of environmentally harmless vegetable oil in the minimum quantity of lubrication(MQL)system in face milling of AISI O2 steel and to optimize the cutting parameters by different... This study aims to examine the usability of environmentally harmless vegetable oil in the minimum quantity of lubrication(MQL)system in face milling of AISI O2 steel and to optimize the cutting parameters by different statistical methods.Vegetable oil was preferred as cutting fluid,and Taguchi method was used in the preparation of the test pattern.After testing with the prepared test pattern,cutting performance in all parameters has been improved according to dry conditions thanks to the MQL system.The highest tool life was obtained by using cutting parameters of 7.5 m cutting length,100 m/min cutting speed,100 mL/h MQL flow rate and 0.1 mm/tooth feed rate.Optimum cutting parameters were determined according to the Taguchi analysis,and the obtained parameters were confirmed with the verification tests.In addition,the optimum test parameter was determined by applying the gray relational analysis method.After using ANOVA analysis according to the measured surface roughness and cutting force values,the most effective cutting parameter was observed to be the feed rate.In addition,the models for surface roughness and cutting force values were obtained with precisions of 99.63%and 99.68%,respectively.Effective wear mechanisms were found to be abrasion and adhesion. 展开更多
关键词 hardmilling minimum quantity of lubrication tool wear grey relational analysis Taguchi method AISI O2 steel
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Effect of Rare Earth Elements on Quantity Growth of Crops 被引量:1
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作者 张自立 常江 +3 位作者 汪成胜 柴绍明 韩修明 李瑞 《Journal of Rare Earths》 SCIE EI CAS CSCD 2002年第4期299-301,共3页
The effects of rare earth on the growth of rice, rape and soybean in three kinds of soils were studied with the method supposed by Economic Co-operation and Development organization (OECD), and the EC50(median growth... The effects of rare earth on the growth of rice, rape and soybean in three kinds of soils were studied with the method supposed by Economic Co-operation and Development organization (OECD), and the EC50(median growth concentration)values were obtained. The inhibition of RE on the growth of rice and rape in red soil and on the growth of soybean in yellow fluvo-aquic soil is higher with stronger poison effects. Compared with other heavy metals such as Hg, Cd, Pb, As, the poison of RE on crops is weaker. 展开更多
关键词 rare earths relative growth quantity half effect concentration
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Solving Arithmetic Word Problems of Entailing Deep Implicit Relations by Qualia Syntax-Semantic Model
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作者 Hao Meng Xinguo Yu +3 位作者 Bin He Litian Huang Liang Xue Zongyou Qiu 《Computers, Materials & Continua》 SCIE EI 2023年第10期541-555,共15页
Solving arithmetic word problems that entail deep implicit relations is still a challenging problem.However,significant progress has been made in solving Arithmetic Word Problems(AWP)over the past six decades.This pap... Solving arithmetic word problems that entail deep implicit relations is still a challenging problem.However,significant progress has been made in solving Arithmetic Word Problems(AWP)over the past six decades.This paper proposes to discover deep implicit relations by qualia inference to solve Arithmetic Word Problems entailing Deep Implicit Relations(DIR-AWP),such as entailing commonsense or subject-domain knowledge involved in the problem-solving process.This paper proposes to take three steps to solve DIR-AWPs,in which the first three steps are used to conduct the qualia inference process.The first step uses the prepared set of qualia-quantity models to identify qualia scenes from the explicit relations extracted by the Syntax-Semantic(S2)method from the given problem.The second step adds missing entities and deep implicit relations in order using the identified qualia scenes and the qualia-quantity models,respectively.The third step distills the relations for solving the given problem by pruning the spare branches of the qualia dependency graph of all the acquired relations.The research contributes to the field by presenting a comprehensive approach combining explicit and implicit knowledge to enhance reasoning abilities.The experimental results on Math23K demonstrate hat the proposed algorithm is superior to the baseline algorithms in solving AWPs requiring deep implicit relations. 展开更多
关键词 Arithmetic word problem implicit quantity relations qualia syntax-semantic model
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行政复议化解涉企行政争议主渠道定位及其实现机制
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作者 王万华 《行政管理改革》 北大核心 2025年第12期33-42,共10页
行政复议化解涉企行政争议的主渠道定位的基本要求包括两方面。一是整体数量要求,指多数涉企行政争议在行政复议渠道中得到化解;二是个案质量要求,指涉企行政争议在行政复议中获得实质化解,实现案结事了。《关于进一步发挥行政复议监督... 行政复议化解涉企行政争议的主渠道定位的基本要求包括两方面。一是整体数量要求,指多数涉企行政争议在行政复议渠道中得到化解;二是个案质量要求,指涉企行政争议在行政复议中获得实质化解,实现案结事了。《关于进一步发挥行政复议监督职能规范涉企行政执法的指导意见》以《中华人民共和国行政复议法》规定为基础,结合涉企行政争议的特点,回应主渠道定位要求,确立了一系列实现机制。回应整体数量要求方面,通过数据赋能,进一步畅通涉企复议申请渠道和完善涉企受理专门机制等。回应个案质量要求方面,明确涉企行政争议案件的重点领域,充分保障企业的复议程序权利,公正审理涉企行政争议,实现涉企行政争议调解依法全覆盖,加大变更决定的适用力度,直接纠正涉企违法或不当行政行为。 展开更多
关键词 涉企行政争议 主渠道 整体数量要求 实质化解行政争议
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基于一测多评及基准关联度研究经典名方旋覆代赭汤中酚酸类成分量值传递规律及影响因素
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作者 汪怡 徐倩菲 +3 位作者 陆杰霖 张泽鹏 李青松 刘菊 《中草药》 北大核心 2025年第5期1596-1606,共11页
目的建立旋覆代赭汤(Xuanfu Daizhe Decoction,XDD)中9种酚酸类成分一测多评(quantitative analysis of multicomponents by single marker,QAMS)定量测定方法,研究酚酸类成分的传递规律,结合基准关联度,分析配伍的影响,并探究“去渣再... 目的建立旋覆代赭汤(Xuanfu Daizhe Decoction,XDD)中9种酚酸类成分一测多评(quantitative analysis of multicomponents by single marker,QAMS)定量测定方法,研究酚酸类成分的传递规律,结合基准关联度,分析配伍的影响,并探究“去渣再煎”的影响。方法制备15批XDD基准样品,以绿原酸为内标物,确定其他8种成分的相对校正因子(fs/i)并计算含量,同时采用外标法测定,比较两者结果差异,计算饮片-水煎液-基准样品的转移率,分析传递规律;制备不同配伍样品,以9种酚酸类成分转移率和指纹图谱相似度为评价指标,计算基准关联度;制备不同煎煮条件样品,检测9种酚酸类成分的转移率。结果QAMS法定量测定结果与外标法无显著差异。新绿原酸、绿原酸、隐绿原酸、咖啡酸、1,3-二咖啡酰奎宁酸、异绿原酸B、异绿原酸A、1,5-二咖啡酰奎宁酸、异绿原酸C的平均转移率分别为147.34%、42.60%、321.53%、131.49%、419.76%、172.93%、18.47%、25.06%、74.68%,酚酸类成分发生降解与异构化可能是部分成分转移率大于100%的主要原因;配伍、煎煮时间、浓缩对9种酚酸类成分的传递均有影响,其中旋覆花与半夏配伍后各指标成分和指纹图谱相似度的基准关联度均大于90%,而“去渣再煎”可以进一步促进酚酸类成分的降解与异构化。结论建立的QAMS法方便、稳定,初步明确从饮片到XDD基准样品中酚酸类有效成分群之间的变化、量值传递规律和可能的影响因素,为XDD的质量控制和制剂开发提供科学依据。 展开更多
关键词 旋覆代赭汤 经典名方 基准样品 一测多评 基准关联度 酚酸类成分 量值传递 影响因素 新绿原酸 绿原酸 隐绿原酸 咖啡酸 1 3-二咖啡酰奎宁酸 异绿原酸B 异绿原酸A 1 5-二咖啡酰奎宁酸 异绿原酸C
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灸法量效关系的研究进展与思考 被引量:28
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作者 谢华 易受乡 +5 位作者 易展 严洁 林亚平 宋炯 彭芬 常小荣 《中华中医药学刊》 CAS 2010年第5期1003-1005,共3页
灸法疗效不仅与施灸所用的材料和穴位的特异性有关,而且与灸量密切相关。近年来,很多学者在灸量与疗效的关系上进行了广泛研究。分别从影响灸量的各个因素概述了灸量和疗效关系的研究进展。希望对以后能更好的研究最佳灸量并指导临床提... 灸法疗效不仅与施灸所用的材料和穴位的特异性有关,而且与灸量密切相关。近年来,很多学者在灸量与疗效的关系上进行了广泛研究。分别从影响灸量的各个因素概述了灸量和疗效关系的研究进展。希望对以后能更好的研究最佳灸量并指导临床提供帮助。 展开更多
关键词 灸量 量效关系 最佳灸量
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人脑胶质瘤微血管数与病理级别及预后关系的初步研究 被引量:6
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作者 甄海宁 章翔 +3 位作者 步星耀 张志文 梁景文 易声禹 《中国神经精神疾病杂志》 CAS CSCD 北大核心 1999年第3期153-155,共3页
目的探讨人脑胶质瘤微血管数(MVQ)与病理级别、术后复发、生存期及患者年龄、性别、肿瘤生长部位的关系。方法应用免疫组织化学ABC法检测63例人脑胶质瘤组织中Ⅷ因子相关抗原(FⅧRAg)的表达,计数MVQ。结果高恶性度... 目的探讨人脑胶质瘤微血管数(MVQ)与病理级别、术后复发、生存期及患者年龄、性别、肿瘤生长部位的关系。方法应用免疫组织化学ABC法检测63例人脑胶质瘤组织中Ⅷ因子相关抗原(FⅧRAg)的表达,计数MVQ。结果高恶性度(Ⅲ、Ⅳ级)胶质瘤MVQ高于低恶性度(Ⅰ、Ⅱ级)胶质瘤(P<0.05)。术后18个月内复发及生存期小于3年者MVQ均明显高于对应组(P均<0.01)。MVQ与患者性别、年龄及肿瘤生长部位无关。结论人脑胶质瘤MVQ与病理级别、术后复发及生存期关系密切。 展开更多
关键词 脑肿瘤 胶质瘤 微血管数 病理级别 预后
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超滤法浓缩提取萝卜POD过程中的数量关系探讨 被引量:4
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作者 马剑敏 王琳 +4 位作者 张晋豫 王林嵩 马晴雯 靳萍 徐存拴 《河南师范大学学报(自然科学版)》 CAS CSCD 1998年第2期64-67,共4页
对超滤法浓缩提取萝卜POD(peroxidase)过程中酶活、比活力、蛋白质浓度及浓缩液体积等的动态变化的初步研究表明:(1)时间与浓缩液的蛋白质浓度、酶活、酶损失率间,浓缩液体积与蛋白质浓度、酶活、比活力及酶活的增... 对超滤法浓缩提取萝卜POD(peroxidase)过程中酶活、比活力、蛋白质浓度及浓缩液体积等的动态变化的初步研究表明:(1)时间与浓缩液的蛋白质浓度、酶活、酶损失率间,浓缩液体积与蛋白质浓度、酶活、比活力及酶活的增加倍数间,以及体积浓缩倍数与酶和蛋白质的得率间的关系,均可用方程y=aebx来表示;(2)时间与透过液的蛋白质浓度及酶活间的关系可用方程y=a+b1x+b2x2+b3x3+bx44来表示;(3)浓缩液蛋白质浓度与酶活及酶的浓缩倍数间,时间与浓缩液体积及透过液的比活力间的关系,均可用方程y=a+bx来表示. 展开更多
关键词 浓缩 提取 萝卜 数量关系 超滤法 过氧化物酶
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灸法研究的现状与发展趋势 被引量:169
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作者 吴焕淦 严洁 +5 位作者 余曙光 徐斌 常小荣 马晓芃 穆敬平 刘慧荣 《上海针灸杂志》 2009年第1期1-6,共6页
从灸材、灸量、艾灸的光热效应、艾灸的调节机制等方面综述灸法研究的现状,提出制约灸法发展的关键问题,并对灸法今后的研究趋势进行了分析与阐述。
关键词 灸法 灸用材料 灸量 量效关系 针灸疗法 红外辐射光谱 作用机制 述评
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2009和2010年中国科技期刊农业科学及相关学科“20%区域”文献数均值统计报告 被引量:84
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作者 房威 朱安 +2 位作者 李杨 张志转 朱永和 《安徽农业科学》 CAS 北大核心 2011年第14期F0002-F0002,F0003,共2页
以文献数分类法为基础,对2009和2010年16个农业科学及相关学科"20%区域"文献数均值进行了计算,为这些学科的期刊分类提供了依据,为期刊的比较和评价工作做了铺垫。
关键词 “20%区域”文献数均值 期刊学科分类 农业科学 农业相关学科
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灰色关联分析筛选抗逆生防木霉发酵条件的研究 被引量:8
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作者 贺字典 吉志新 +2 位作者 高玉峰 胡铁锋 武会清 《西北农业学报》 CAS CSCD 北大核心 2015年第3期163-169,共7页
为明确木霉生防效果的高低与木霉菌的产孢能力和在土壤中定殖力的高低的关系,采用灰色关联分析方法研究了397株木霉生防效果与菌丝生长速度、产孢量、耐低温性等抗逆性状的相关性,对优势菌株的发酵条件及生防效果进行测定。结果表明,TRS... 为明确木霉生防效果的高低与木霉菌的产孢能力和在土壤中定殖力的高低的关系,采用灰色关联分析方法研究了397株木霉生防效果与菌丝生长速度、产孢量、耐低温性等抗逆性状的相关性,对优势菌株的发酵条件及生防效果进行测定。结果表明,TRS060186和TRW079634两个菌株与抗逆性状的相关性最高,关联度系数分别为0.874和0.757;TRW079634和TRS060186对黄瓜枯萎病的相对防效分别为88.7%和70.1%;温度是影响2个菌株产生不同类型孢子的关键条件,TRS060186在20℃产生分生孢子,28℃产生厚垣孢子。TRW079634则于28℃产生分生孢子,25℃有利于产生厚垣孢子。因此,木霉的适应性强弱是影响木霉菌生防效果的最主要的因子。 展开更多
关键词 木霉 灰色关联分析 黄瓜枯萎病 产孢量
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