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Search Results: 1 - 10 of 111040 matches for " 周超 "
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EXPLORATION AND TEST ON A NEW TYPE OF PASTY PROPELLANT SUPPLY PRINCIPLE
膏体推进剂供给系统新方案探索与初步验证


力学与实践 , 2008,
Abstract: According to the requirement of the pasty propellant rocket engine design and pasty propellant pipe flow experiment, a new type of pasty propellant supply system is proposed. This scheme uses variable frequency motors and frequency transformers as drive forces and screw/ nut, gearbox as drive components. The design can guarantee a accurate flow rate. The pipe flow experiment of HTPB was conducted with established supply platform. The flow rate and pressure drop were obtained. The experiment result was analyzed with Non-Newtonian flow theory. The viscosity data acquired from the results are consistent with those in literature. From the pipe flow experiment, it is concluded that the scheme of the new supply system is feasible and the parameters of the system are correct.
基于区域瓦斯治理的钻爆抽一体化技术及应用

煤炭工程 , 2011,
Abstract: 摘要针对我国高瓦斯煤层赋存特点及目前煤矿区域瓦斯治理过程中存在的问题,理论分析了煤与瓦斯耦合作用下爆生裂隙形成机理,开发了爆破抽放钻孔密封材料及配套注浆设备;采用理论研究,数值模拟和现场测试相结合的方式,研究了基于区域瓦斯治理的高瓦斯低透气性煤层的钻爆抽一体化卸压增透技术,利用爆破孔内爆生气体的尖劈、松爆和控制孔的控制、导向、排放瓦斯作用以及通过PD复合材料技术密封抽放钻孔的作业方式,达到整体卸压、增透、抽放瓦斯和消除突出的目的,并在国内有关矿井进行了应用。应用结果表明,该技术可显著提高区域抽采效率,缩短区域抽采时间,具有广泛的应用前景。
膏体推进剂供给系统新方案探索与初步验证

力学与实践 , 2008, DOI: 10.6052/1000-0992-2007-419
Abstract: 依据膏体推进剂火箭发动机设计和膏体推进剂管道流动实验需求,提出了一种新型膏体推进剂供给系统方案.该方案以变频电机作为驱动力,螺杆/螺母、减速器等作为传动部件,可以满足实验中对流量精确控制的要求.利用该供给平台进行了膏体推进剂替代物-丁羟(端羟基聚丁二烯)的管道流动实验,测得了压力与流量的关系曲线.以非牛顿流体流动理论为基础,分析了丁羟管道流动实验结果,得出的黏度数据与文献吻合,初步验证了该供给方案的可行性以及原理性平台各项参数的正确性.
低温红外系统光机结构设计

红外与激光工程 , 2013,
Abstract: 随着红外技术的发展,大口径望远镜越来越多地使用了红外设备终端。红外设备需要在低温下工作,这就给红外系统的光机结构设计带来了难度。为了解决光学部件需要安装定位精确,又要保证在低温环境下不会因为热应力导致破坏的问题,从理论上介绍了运动学定位的原理,针对光学系统中用到的反射镜、透镜、滤光轮等进行了详细的结构设计,实现了运动学安装定位。通过这些设计可以很好地解决光学件在冷却过程中的精确定位和无应力之间的矛盾,保证光学系统的安全,同时保证光学系统的成像质量。该研究结果对于红外光学系统的结构和热设计有一定的参考价值。
基于Jones矢量的单粒子散射Mueller矩阵的数值计算
Numerical Calculation for Mueller Matrix of a Single Particle Based on Jones Vectors
 [PDF]

, 王清华, 李振华
Optoelectronics (OE) , 2015, DOI: 10.12677/OE.2015.52005
Abstract:
本文推导了基于Jones矢量的单粒子散射的数学表达式;根据Jones矢量与Stokes参量的内在联系,给出了由典型偏振态的Jones矢量出发,计算Mueller矩阵的具体步骤。通过数值模拟得出单粒子对称系统中:二维Mueller矩阵4行4列共16个子图关于对角线对称;m41,m42,m43,m14,m24,m34数值为零;二维Mueller矩阵中非零元素子图中仅5幅独立,其余可通过旋转变换得到。
The formulae of a single particle’s scattering based on Jones vectors are derived. Then, the scat-tering Jones vectors of the single particle for the typical polarization states can be calculated. Fur-ther, the Stokes parameters can be obtained according to the scattering Jones vectors. The proper linear combination of the typical scattering Stokes parameters will provide the elements of Mueller matrix. The simulations for the single particle show that the subgraphs of the 2D Mueller matrix are symmetrical about the diagonal. The values for m41, m42, m43, m14, m24, m34 are all zeros. Only five subgraphs for the nonzero elements are independent and the others can be gained by rotation.
药用植物茅苍术资源的开发利用现状
Development and Utilization of Medicinal Plant Atractylodes lancea
 [PDF]

赵丹, 佳宇, 戴传
Botanical Research (BR) , 2016, DOI: 10.12677/BR.2016.53011
Abstract: 药用植物茅苍术是我国著名的道地药材。由于近年来对茅苍术的肆意挖掘,导致茅苍术产量锐减,因此亟待保护。本文将综述茅苍术资源现状及人工栽培存在问题,总结生物技术手段在茅苍术药材生产中的应用,为茅苍术的开发利用和保护提供参考。
Atractylodes lancea is a famous Chinese genuine medicine used for thousands of years. Because of over exploitation, the storage amount of Atractylodes lancea reduced sharply in recent years. Therefore, A. lancea needs urgent protection. This paper reviews the existing resources of A. lancea and the problems in the medicinal cultivation, and summarizes the biotechnology tools that have been used in the production of A. lancea, aiming at providing reference for the development, utilization and protection of A. lancea.
施肥对马尾松幼苗及根系生长的影响
,*
南京林业大学学报(自然科学版) , 2011, DOI: 10.3969/j.jssn.1000-2006.2011.03.014
Abstract: 采用盆栽试验研究了不同施肥处理下马尾松苗木苗高、地径、根系的动态变化。研究表明:施肥对马尾松地上及根系生长有一定促进作用。其中,苗高、地径在单施磷肥时生长最好,到12个月时,分别为16.23、0.29cm,高于对照67.5%及155.1%;根长最长为54.58cm/株,高于对照69.2%;主根长相对较短(20.67cm/株),仅高于对照29.1%;根表面积较大,为11.86cm2/株,明显高于对照104.8%;根尖数较多(239个/株),高于对照16.1%,侧须根发达。其次是氮、磷、钾肥混施效果较好,而单施氮肥则效果不佳。因此,在马尾松苗木培育过程中,适当施用磷肥可促进大苗、壮苗培育。
广东省植物发育生物工程重点实验室简介

植物学报 , 2002,
Abstract:
广东省植物发育生物工程重点实验室简介

植物学报 , 2003,
Abstract:
刑事证据法学研究的回溯与反思
,
中外法学 , 2004,
Abstract:
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