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Search Results: 1 - 10 of 62045 matches for " 江光 "
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卷扬机钢丝绳欧拉公式及欧拉衰减的研究
Theoretical Study of Euler’s Formula and Loss Elimination Effect on Rope Windings of Winch Drum
 [PDF]

祺琦,, 王建明
International Journal of Mechanics Research (IJM) , 2016, DOI: 10.12677/IJM.2016.51002
Abstract:
本文对卷筒钢丝绳缠绕过程进行分析,多层缠绕钢丝绳卷筒的受力实际随钢丝绳缠绕位置不同而变化,具有时变特性。基于欧拉挠性体摩擦公式,将公式推导至多圈多层,建立更准确的多层缠绕卷筒受力计算模型,进行详细理论分析。对由于钢丝绳之间摩擦力,以及钢丝绳、筒体的变形所导致的绳圈卸压效应进行研究。当钢丝绳缠绕圈数增加时,先前绕上的钢丝绳圈的张力发生变化,有绳圈卸压效应,即欧拉衰减现象。并对表示绳圈卸压的张力系数,提出合理计算公式,便于应用。
Rope and rope drum are important parts of winding machine and should be improved to enhance security issues. Theoretical analysis of drum dynamic force during the course of spooling into drums in multi-layer winding is introduced. By study and deduction of Euler’s formula, a more accurate method is introduced to study the multi-layer winding drum force. Analytical model of rope is studied to illustrate the loss elimination effect. Course of the rope load relieving is explained. And then the analytical equations for calculation and pragmatic numerical estimation of rope tensional coefficient are revealed.
低杂波电流驱动天线耦合的三维模型
The 3D Model of Antenna Coupling in LHCD System
 [PDF]

朱学, 丁伯,, 谢纪康, 刘艳丽
Modern Physics (MP) , 2012, DOI: 10.12677/MP.2012.23007
Abstract: 通过数值计算对低杂波波导阵天线的耦合特性进行了模拟。采用三维天线耦合模型,考虑了波导沿环向及极向都为有限尺度,以及TETM模式的相互耦合。用数值积分的方法计算等离子体表面阻抗,利用此边界条件及波导口处电磁场的连续性。计算各波导在TE10主模2.45 GHz频率的低杂波信号的激励下,各TETM波导模式的反射系数。然后计算天线辐射的低杂波频率的功率谱分布。
The coupling performance of grills for lower hybrid frequency is obtained by digital simulation. The three dimensional model is adopted, namely considering the finite poloidal and toroidal sizes of the grills and coupling between TE modes and TM modes. The plasma surface impedance is estimated by digital integral method, and this boundary condition and the electromagnetic field continuity at the grills’ mouth are used. Under the main mode of 2.45 GHz lower hybrid frequency excited in the grills, the reflection factors of the TE and TM waveguide modes can be calculated. Then we obtain the lower hybrid frequency power spectrum distribution sent by the antennas.
焙烧—氰化法从铜精矿中提取金银铜的试验研究
,于永
黄金科学技术 , 2013,
Abstract: 对某浮选铜精矿进行了焙烧一氰化法提取金、银和铜的工艺方法研究。研究表明,将浮选金精矿(0.074mm所占比例>90%)于600℃条件下焙烧,产生的SO2用于制酸,焙砂采用5%H2SO4浸取回收铜,酸浸渣先用新型调整剂(NH4HCO3+NaOH)调浸出液pH值≈9.5,以氰化法进行浸出。其金、银和铜的浸出率分别达到98.18%、32.17%和93.6%,经济效益和社会效益显著,为铜精矿的湿法提取工艺提供了一个有效的工艺方法。
小麦雄性不育研究进展
红梅,
生物技术通报 , 2009,
Abstract: 雄性不育是植物中的一种普遍现象,而雄性不育是利用杂种优势提高作物产量和品质的基础,因此小麦雄性不育的理论机制研究对农业生产具有重要的指导意义。对小麦雄性不育类型及遗传、生理生化不育机制、定位及分子生物学研究进行了综述,并探讨了今后该领域的研究前景。
一个新的ras调节靶标——血管紧张素转化酶2
翠娥,
食品科学 , 2013,
Abstract: ?血管紧张素转化酶2(ace2)是人类ace的同系物,它通过肾素-血管紧张素系统(ras)新的作用分支ace2-血管紧张素-(1-7)-mas受体(ace2-ang-(1-7)-mas)轴反向调节经典的ace-angⅱ-at1受体轴,不平衡若持续,会导致心血管、肾、肺和中枢神经系统的病理生理。目前已发现ace2激动剂的类似物广泛存在于天然植物性原料中。
聚乙烯醇-羧甲基纤维素钠共混膜的制备与性能
,,李玲?,建明
功能高分子学报 , 2009,
Abstract: 用溶液共混法制备聚乙烯醇 羧甲基纤维素钠(PVA-CMC)共混膜。用SEM、FT-IR、DSC对其进行表征,并测试了膜的性能、交联速率和凝胶分数。结果表明:共混膜组分之间相容性良好,综合力学性能比单一组分有所提高。利用磷酸和氯化钙溶液可以有效地对共混膜进行交联,使其在醇水混合溶液中稳定存在;且交联过程未引入有毒物质,这种共混膜材料有望用作软骨修复材料的基体。
褐飞虱致害性研究进展
Advancement in Studies on the Virulent of Brown Plan-thopper
 [PDF]

荆胜利,, , 李刚, 刘虹, 陈雁, 覃瑞
Botanical Research (BR) , 2013, DOI: 10.12677/BR.2013.21002
Abstract:

褐飞虱(Nilaparvata lugens St?l,Homoptera: Delphacidae)是一种重要的水稻害虫,可以直接取食或将病菌和病毒传给水稻,从而给粮食生产带来巨大损失。目前,由于能克服寄主抗性的新褐飞虱致害性种群出现,导致其危害越来越严重。研究褐飞虱致害性遗传变异规律对于抗性品种的选育与应用具有很重要的意义。本文就褐飞虱致害性种群的田间发生情况,鉴定方法,遗传分析,分子生物学和内共生菌等方面进行了阐述。
Brown planthopper (Nilaparvata lugens St?l) (Homoptera: Delphacidae) is economically impor- tant pest on rice that feed directly or serve as vectors of pathogenic microorganisms and viruses to crops, re- sulting in significant damage and yield losses for farmers. In recent decades, brown planthopper has become notorious due to the emergence of new, virulent populations that can overcome host resistance. Thus, it is important to study virulent variation of the brown planthopper for the breeding and applying of resistant rice varieties. In this study, I review that the virulent population of brown planthopper distributed in rice fields and that the other content included the method of identification, the analysis of genetic basis, molecular boil- ogy and the relation of virulence with symbionts.

GaAlAs薄层组份及其纵向分布的电调制光谱测量
刘继,德生
红外与毫米波学报 , 1986,
Abstract: 本文报道了用电调制反射光谱法测量GaA1As的能隙与组份的依赖关系,以及外延薄层和异质结界面处组份的纵向分布。利用样品在紫外区的吸收很大、透入深度较小的特点,结合阳极氧化和化学腐蚀剥层技术,测量了薄层和异质结固溶体样品组份的纵向分布。
脑网络研究述评
A Review on Researches of Brain Networks
 [PDF]

涂燊,, 曹晓君, 王婷,, 张庆林
Advances in Psychology (AP) , 2013, DOI: 10.12677/AP.2013.36042
Abstract: 认知神经科学传统的定位式研究方法越来越显示出其局限性,近些年兴起的脑网络研究可以克服这种局限。脑网络研究可以从以下几个方面进行主要的了解:1) 脑网络研究的必要性;2) 脑网络介绍,包括结构网络、功能网络和它们所具有的网络性质,还有两者之间关系的简单探讨;3) 临床网络研究;4) 研究新趋向,包括模型取向及脑网络的动态变化研究;5) 脑网络研究的局限性及挑战。
 The accumulating evidence shows that the traditional modular paradigm used in the cognitive neuroscience has serious limitations in understanding the brain. However, brain network may overcome the limitation. Brain networks can be understood from following respects: 1) the necessity of brain network studies; 2) introduction to brain networks, including how to construct structural and functional brain networks, properties and relations; 3) clinical brain network studies; 4) the new direction for future brain network studies, including modeling and dynamical changes of brain networks; 5) the limitations of brain network studies and challenges.
多学科技术综合的重力活塞取样技术—以“海洋六号”船的重力活塞取样为例
Gravity-Piston Sampling System with Multi-Disciplinary Comprehensive Technologies—By Introducing the Gravity-Piston Sampling of Haiyangliuhao
 [PDF]

李柯良, 于彦, 朱峰, 任旭, 杨楠
Adances in Marine Sciences (AMS) , 2015, DOI: 10.12677/AMS.2015.23005
Abstract:
重力活塞取样现在发展为一门多学科技术综合的技术系统。通过多波束调查,浅层物探调查等地形,地貌,地层的调查;导航系统和动力定位系统的精确定位;优良可靠的重力活塞取样器;强大的绞车收放系统和操作信息监控系统配合使用。可以保证极高的取样成功率,有效保证获取一定数量的高品质的柱状沉积物。通过介绍大洋科考中“海洋六号”船的重力活塞取样方法,说明多学科技术综合应用在重力活塞取样过程中发挥的重要作用。
Gravity-piston sampling now develops to a technical system with multi-disciplinary comprehensive technologies. The multi-beam and shallow geophysical survey of terrain, landscape and stratum, the precise positioning of navigation system and dynamic positioning system, the reliable gravity- piston sampler, and the coordinate application of powerful winch launch and recovery system and information operation and monitoring system could guarantee a certain number of high-quality core sediments to ensure the sampling success rate. By introducing the gravity-piston sampling of Haiyangliuhao in ocean scientific expedition, it is shown that the multi-disciplinary comprehensive technologies play an important role in marine geological sampling.
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