优质春小麦新品种高原314的性状表现及推广前景

高原314春小麦新品种在青海省乐都县川水地区突出表现为产量高、品质优、落黄好,可以作为现有水地春小麦替代品种大面积推广应用.

春小麦新品种高原314及其栽培技术

高原314是中国科学院西北高原生物研究所农业中心通过有性杂交培育的春小麦新品种，2001年12月通过青海省农作物品种审定委员会审定，品种原代号为95-314，现定名为高原314，属小麦Var. graecum Korn的变种。品种组合为：高原602 * {[ST142 * [(82宁182 * 82原11) * 47-2]] * [(78-17-3 * 83-228-3) * (Chanal * 338)]}F_3。

Structural Failure Analysis and Numerical Simulation of Micro-Accelerometers under Impulsive Loading

Micromachined accelerometer is a kind of inertial MEMS devices, which usually operate under intensive impact loading. The reliability of micromachined accelerometers is one of the most important performance indices for their design, manufacture and commer

低速物体的非线性水波理论综述

<正> 一、问题的提出 虽然造船工程师们对低速船波的产生问题可能没有很大的兴趣,可是这一问题有其基本的重要性。在速度很低的情形,船波很小,因此,在船舶设计中可以不考虑低速波阻。当速度趋近于零时,通常在有限速度下预言波阻的方法与公式不再适用。也就是这些方法的数学解在低速时不是一致有效。因此,我们必须回答这样的问题:在多么低的速度时,这些标准方法不再适用?

托卡马克中等离子体平衡的数值计算

<正> 一.引言 环形等离子体的理想磁流体力学平衡的自由边界问题,等人做了研究,但是仅给出a/R《1的圆截面等离子体柱平衡的分析结果。目前建造大型托卡马克装置时,要求纵横比a/R比较大,并且要能够准确的求出等离子体的平衡位形。本文用超松弛法求解平衡方程,得到计算自由边界问题的磁面的方法。自由边界问

参加波兰流体力学学会记要

<正> 今年9月3—14日波兰科学院在波兰南部库鲁力查城召开了流体力学学会。中国科学院应波兰科学院的邀请,派遣笔者参加这次学会,宣读论文,并参观一些有关流体力学的实验室。学会是由波兰科学院院士布考斯基、隆次和鲍恩德三人主持的。波兰科学院

Three-dimensional finite element analysis of composites with coated spherical inclusions

A three-dimensional finite element analysis has been used to determine the internal stresses in a three-phase composite. The stresses have been determined for a variety of interphase properties, the thicknesses of the interphase and the volume fractions of particles. Young's modulus has been calculated from a knowledge of these stresses and the applied deformation. The calculations show that stress distributions in the matrix and the mechanical properties are sensitive to the interphase property in the three-phase composites. The interfacial stresses in the three-dimensional analysis are in agreement with results obtained by an axisymmetric analysis. The predicted bulk modulus in three-dimensional analysis agrees well with the theoretical solution obtained by Qui and Weng, but it presents a great divergence from that in axisymmetric analyses. An investigation indicates that this divergence may be caused by the difference in the unit cell structure between two models. A comparison of the numerically predicted bulk and shear modulus for two-phase composites with the theoretical results indicates that the three-dimensional analysis gives quite satisfactory results.

半焦在流化床燃烧中Cl元素影响CO氧化的试验

在非均匀布风的流化床燃烧系统中进行了半焦中添加PVC/NaCl的混烧试验,研究了Cl元素对燃烧中CO氧化的影响以及混烧时SO_x等污染物的生成规律.试验结果表明,半焦与PVC/NaCl混烧在技术上可行,添加Cl元素抑制CO氧化,加入PVC增加SO_2排放,而加入NaCl则减少SO_2排放.

钝体尾流控制机理及方法研究进展

首先从涡脱落生成理论出发对钝体尾流控制方法进行了分类,并简单介绍r国内尾流控制研究情况.之后介绍r我们用窄条或小方柱取代小圆柱后,对Strykowsky和Sreenivasan控制方法的改进及其在高雷诺数下对圆柱和方柱尾流涡脱落的有效抑制情况,并探讨了控制件钝度对抑制效果的影响.第3部分用实验数据对各个涡脱落生成模型做了分析与检验,指出控制件方法的机理与改变钝体分离位置、减小钝体背压吸力、改变流动的腱向相关性、防止钝体两侧剪切层相互作用等无关,而与钝体近尾流速度剖面的局部修正及其稳定性的改变有关.最后简单介绍了控制件方法今后研究工作展望及其工程应用前景.

环与杆高速碰撞动态响应的分析和预测

采用量纲分析的方法，讨论了环与杆高速碰撞时影响杆被击断的主要因素，分别给出了相对临界速度、临界方位角及环的临界厚度与主要物理参数的函数关系，并通过计算机仿真确定这种函数关系。

Mechanisms of femtosecond laser-induced breakdown and damage in MgO

Single-shot laser damage threshold of MgO for 40-986 fs, 800 nm laser pulses is reported. The pump-probe measurements with femtosecond pulses were carried out to investigate the time-resolved electronic excitation processes. A theoretical model including conduction band electrons (CBE) production and laser energy deposition was applied to discuss the roles of multiphoton ionization (MPI) and avalanche ionization in femtosecond laser-induced dielectric breakdown. The results indicate that avalanche ionization plays the dominant role in the femtosecond laser-induced breakdown in MgO near the damage threshold. (c) 2005 Elsevier B.V. All rights reserved.

Energy transfer between silicon-oxygen-related defects and Yb3+ in transparent glass ceramics containing Ba2TiSi2O 8 nanocrystals

We report on the conversion of near-ultraviolet radiation of 250-350 nm into near-infrared emission of 970-1100 nm in Yb3+-doped transparent glass ceramics containing Ba2TiSi2O8 nanocrystals due to the energy transfer from the silicon-oxygen-related defects to Yb3+ ions. Efficient Yb3+ emission (F-2(5/2)-> F-2(7/2)) was detected under the excitation of defects absorption at 314 nm. The occurrence of energy transfer is proven by both steady state and time-resolved emission spectra, respectively, at 15 K. The Yb2O3 concentration dependent energy transfer efficiency has also been evaluated, and the maximum value is 65% for 8 mol % Yb2O3 doped glass ceramic. These materials are promising for the enhancement of photovoltaic conversion efficiency of silicon solar cells via spectra modification.

Optical interconnection for neural networks by use of a self-imaging function

A grating-lens combination unit is developed to form a scaling self-transform function that can self-image on scale. Then an array of many such grating-lens units is used for the optical interconnection of a two-dimensional neural network, and experiments are carried out. We find that our idea is feasible, the optical interconnection system is simple, and optical adjustment is easy. (C) 1998 Optical Society of America.

Parallel plate interferometer with a reflecting mirror for measuring angular displacement

A parallel plate interferometer with a reflecting mirror for measuring angular displacement is proposed. A deflection angle of a beam caused by an angular displacement is amplified by use of a reflecting mirror to increase the optical path difference (OPD) in the plane-parallel plate, which provides high sensitivity of the phase measurement. Detection of light transmitted through the plane-parallel plate with a position sensitive detector (PSD) enables high accurate measurement of the initial angle of incidence to the plane-parallel plate with insensitivity to stray light. The improved parallel plate interferometer achieves a measurement repeatability of 10(-8) rad. (C) 2007 The Optical Society of Japan.

隔板玻璃表面宽光谱增透膜的制备与性能

利用溶胶-凝胶提拉方法在隔板玻璃表面涂制得到由TiO2与SiO2组成的λ/2-λ/4型宽光谱增透膜。通过溶胶粘度、凝胶时间及红外光谱等研究了TiO2涂膜溶胶的稳定性与相应膜层性能，测试了双层增透膜的透过率、抗高能氙灯辐照性能及使用性能等。结果表明，控制合适的原料配比、降低薄膜烘烤升温速率，可得到适于大面积涂膜的稳定TiO2溶胶，有效改善TiO2膜层质量；隔板玻璃表面增透膜在450-900nm光谱范围内平均透过率高达约98％，使“神光-Ⅱ”第九路主放大器的实际增益提高5．5％-6．5％且具有良好的抗高能氙灯