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Search Results: 1 - 10 of 276937 matches for " 李勇 "
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广东省燃煤电厂粉煤灰质量调研
Survey of the Quality of the Fly Ash from Coal-Fired Power Plant in Guangdong Province
 [PDF]


Advances in Energy and Power Engineering (AEPE) , 2014, DOI: 10.12677/AEPE.2014.24006
Abstract:
根据商品混凝土市场对粉煤灰质量方面的要求,组织对17家燃煤电厂粉煤灰进行质量跟踪检测,分析研究其质量状况,就提高现有资源利用效益和控制产品质量提出意见建议。
According to the fly ash quality’s requirements of the commercial concrete market, 17 coal-fired power plants have been traced and checked for coal ash quality. By analysis and research quality, suggestions of improving the efficiency of the existing resources and controlling the quality of the products have been put forward.
一类新的脉冲积分不等式及其应用
A Class of New Impulsive Integral Inequality and Its Application
 [PDF]

自尊,
Pure Mathematics (PM) , 2013, DOI: 10.12677/PM.2013.31007
Abstract:
本文建立了一类新的非连续函数积分和不等式,其不等式左端为未知函数的非线性因子,右端和项中也为未知函数的非线性因子。我们给出了未知函数的界的估计。最后,我们用求得的结果给出了脉冲微分方程解的估计。
In this paper, we establish a class of new integro-sum inequality for discontinuous function, and the left hand of the inequality is a nonlinear factor of unknown function, and the sum-term of the right hand of the inequality for the unknown function is also a nonlinear factor. We obtain the estimation of bound of the unknown function. Finally, we apply our result to present estimation of the solution of impulsive differential equation.
人参皂甙对神经系统和内分泌系统的研究进展
Research Progress on Neurological System and Endocrine System of Ginsenoside
 [PDF]

刘睿,
Hans Journal of Food and Nutrition Science (HJFNS) , 2016, DOI: 10.12677/HJFNS.2016.52006
Abstract:
人参皂甙一种极具药用价值的化学物质,具有广泛的药理活性。本文将以近年来国内外研究人参皂甙的报道为基础,对人参皂甙对机体神经系统和内分泌系统的保护作用的研究进展作一综述,为预防和治疗疾病及进一步研究开发人参皂甙类药物提供相关信息。
Ginsenoside is an important chemical material with a lot of pharmacological activities. According to domestic and foreign research reports on ginsenoside in recent years, this article reviewed research advance in ginsenoside’s protective effect on the nervous system and endocrine system, to provide relevant information for prevention and treatment of diseases, also for further drug development.
空间物体光照特性分析与应用
Analysis and Applications on Sunlighting Characteristics of Space Objects
 [PDF]

, ,, 孙鹏云
Journal of Aerospace Science and Technology (JAST) , 2014, DOI: 10.12677/JAST.2014.23006
Abstract:
本文分析太阳、地球和空间物体轨道运动的基本耦合关系,构建空间物体光照问题的一般数学模型;对空间物体光照的影响参数进行分析,探讨不同参数的变化范围、周期及对目标光照的影响程度,针对常见的圆轨道讨论长半轴对受晒因子的影响,建立圆轨道的全轨道受晒方程;进一步探讨空间物体光照特性在空间目标光学探测与跟踪、太阳敏感器、太阳光压作用、空间太阳能发电等空间活动中的应用,分析给出主要应用的发展方向、关键技术或技术性能,为相关研究提供理论参考。
Based on the primary orbital relation among sun, earth and space object, the mathematic model of space object sunlighting problem is made. Effects of various parameters and their change field, period, etc. for space target sunlighting are analyzed. As the most familiar satellite orbit, the rela-tion between the sunshine factor of the circle orbit and its semi-major axis is discussed, and whole orbital sunshine equation of circle orbit is made. Furthermore, many applications of sunlighting characteristics of space objects in space activities are studied, such as the optical detecting and the tracking of space targets, the sun sensor, the radiation pressure effect and the space solar power system. And developing aspects, key techniques or technical characteristics of these applications are analyzed. These results will help to study practical problems further.
数字阵列雷达工程实现技术难点分析
The Technology Problems in the Engineering of Digital Array Radar
 [PDF]

晓俊,
Instrumentation and Equipments (IaE) , 2015, DOI: 10.12677/IaE.2015.34021
Abstract: 数字阵列雷达是一种接收和发射波束都采用数字波束形成技术的全数字阵列扫描雷达,是有源相控阵雷达和数字雷达的最新发展方向。本文从数字阵列雷达的基本组成入手,首先分析了数字阵列雷达动态范围低要求、超低副瓣、低截获概率、宽角度扫描等主要特点,最后讨论了工程实现过程中存在的诸如数字TR组件、宽带信号、超低副瓣和通道一致性等技术难点,为数字阵列雷达的深入发展指明了方向。
Digital Array Radar (DAR) is a fully digitized phased array radar in which digital beam forming technique is used both in receiving and transmitting. Firstly, this paper introduced the typical ar-chitecture of DAR. Then, it analyzed the characteristics of DAR, such as the low demand of dynamic range, the ultra low side-lobe, the low probability of Intercept and the broad field of regard. Finally, it discussed the technology problems in the process of engineering realization, including the digital TR Module production, the broadband realization, the ultra low side-lobe and the channel consistency technique. It will be helpful for the fully development of DAR.
超高压致死微生物的研究进展

微生物学通报 , 1995,
Abstract: 超高压致死微生物的研究进展李勇(彭城大学食工系,徐州221008)食品的腐败变质主要由微生物而引起,所以热力杀菌在食品加工中得到广泛应用。但高效的热力杀菌常会使食品产生加热臭、热敏性营养成分损失、变色及其他难以克服的变质现象。对此日美等国自1990年...
寿称人瑞,学为人师——著名植物学家胡秀英先生

中国科学院研究生院学报 , 2005,
Abstract:
黄土高原土壤抗冲性机理初步研究

科学通报 , 1990,
Abstract: 黄土及其上面发育的土壤无根系盘绕、固结,抗冲性很差,是导致黄土高原水土流失严重、生态环境恶化的重要内在原因.因此,研究该区土壤抗冲性的成因,是解决土壤侵蚀预测预报和水土保持综合治理的重大理论和实践问题.关于土壤抗冲性这一概念最早由朱显谟在60年代,根据黄土高原土壤抗侵蚀能力的特点,提出应把土壤抗蚀性和抗冲性明确区分开来进行研究,但有关这方面的系统研究至今尚未见报道.作者自1987年以来对黄土高原土壤剖面的
黄土高原植物根系强化土壤渗透力的有效性

科学通报 , 1992,
Abstract: 研究表明,在黄土丘陵陡坡上积极建造人工植被,“拦蓄水分,就地入渗”,是提高土壤渗透能力,防治土壤侵蚀的关键措施。迄今,有关植被地上部分对土壤渗透力的影响研究甚多,但涉及地下部分根系强化土壤渗透作用的定量研究尚未见报道。本文首次以定量描述植物根系强化土壤剖面各层次渗透力的作用及其相互关系为基础,建立根系强化土壤渗透力有效性的数学模型,并对模型在水土保持优良草树种的选择及其合理配置中的应用进行讨论。
黄土高原植物根系提高土壤抗冲性的有效性

科学通报 , 1991,
Abstract: 黄土高原植物根系对提高土壤抗冲性的作用是在对该区土壤抗冲性系统研究的基础上开辟的一个新的研究领域。目前已定量研究了几种乔灌草根系对土壤抗冲性的强化效应。结果表明,植物根系强化土壤抗冲性的能力主要取决于有效根密度在土壤剖面中的分布盘绕状况,有效根密度的物理基础是100cm~2土壤截面上≤1mm须根的个数。本文首次从
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