剪切载荷下肋板的屈曲分析与优化

利用ANSYS有限元方法分析了一系列的肋板，研究了加强肋的作用，提出了 优化肋设计的限制条件. 结果表明，由横向肋板产生的栅格数目不能小于肋板的长宽比. 换 句话说，横向加强肋必须把平板的长度划分为小于等于宽度的段. 结果还显示，加强肋的优 化几何特性与板的屈曲从整体模态到局部模态转变点相应. 而且，所有具有相似长宽比和肋 数的肋板，具有一个特定的比值$EI_{s}/aD$, 此时抗剪应力最佳.     

Disulfuration and hydrosulfuration of an alkyne at a 1,2-dicarba-closo-dodecaborane-thiolate ligand

The reaction of the dinuclear cobalt compound [(CpCoS(2)C(2)B(10)H(10))(CpCoSC(2)B(10)H(11))(n-C(4)H(9)S)] (1) with HC≡CC(O)Fc leads to the cobalt-free products (C(2)B(10)H(10))(SCH=CHCOFc)(2) (4-6), (S(2)C(2)B(10)H(10))(HC=CCOFc) (7), and (C(2)B(10)H(11))(SCH=CHCOFc) (8, 9). 4-6 are produced by hydrosulfuration of the alkyne at the 1,2-dicarba-closo-dodecaborane-dithiolate ligand with the generated vinyl groups in Z/Z, Z/E and E/E configurations, respectively. In 7, the alkyne is added to 1,2-dicarba-closo-dodecaborane-dithiolate at the two sulfur sites. 8 and 9 are the products of alkyne hydrosulfuration at the 1,2-dicarba-closo-dodecaborane-1-monothiolate ligand with the generated vinyl group in either Z or E configuration. The treatment of 1 with HC≡CCO(2)Me gives rise to the parallel products (C(2)B(10)H(10))(SCH=CHCO(2)Me)(2) (10-12) and (C(2)B(10)H(11))(SCH=CHCO(2)Me) (13, 14). All of the new compounds have been characterized by IR, NMR, elemental analysis and mass spectroscopy. The structures of compounds 4, 7, and 8 have also been determined by single-crystal X-ray diffraction analysis.     

Rapid transfer alignment of laser SINS using quaternion based angular measurement

A novel rapid transfer alignment algorithm for laser strapdown inertial navigation system (SINS) is studied. Transfer alignment have typically relied on velocity measurements from the master SINS as the source of alignment information, but lever arm error must be compensated accurately while velocity information is utilized, all most every quaternion based error model is nonlinear, so nonlinear filtering algorithms are need, suffering from computational complex and large error. Aim at these problems, a novel improved rapid transfer alignment algorithm formulation is presented, applying quaternion to built the process and measurement models, the improvement employs a special manipulation of the measurement equation results in a linear pseudo-measurement equation, thus the classical linear Kalman filter is employed to estimate the state, need not lever arm error compensation, results in the reduce of computational burden. Observability analysis of this new transfer alignment algorithm has been done based on the piece-wise constant system (PWCS) method, results show that the presented algorithm can accomplish the initial alignment task perfectly. A transfer alignment simulation system is also developed for the evaluation and analysis of the presented algorithm, simulation results are confirmed with the theoretical conclusion, which can achieve the transfer alignment accuracy about 1 mrad within 10 s.     

国产二十万千瓦汽轮机高中压缸准三维气动热力分析

本文采用准三维计算方法分析了国产二十万千瓦汽轮机在运行工况条件下的高中压缸气动热力性能.S1计算分析了叶型表面等摘马赫数分市情况及叶型的性能，S2计算得到了沿叶片高度的气动热力参数分布并分析了主要的通流性能参数，最后为改造设计提出了若干建议．     

叶栅边界层转捩的实验研究与一个新的综合经验准则

叶栅边界层转捩的实验研究与一个新的综合经验准则蒋洪德，仲永兴，凌君（中国科学院工程热物理研究所北京１０００８０）（中国航空工业总公司６２４所）关键词转捩实验，经验准则１前言现代航空发动机的风扇、压气机和涡轮叶栅在工作状态下弦长雷诺数一般在１０５～１０...     

瓦斯煤尘爆炸火焰光谱的实验研究

本文概述了瓦斯煤尘爆炸火焰光谱实验研究的重要性,我们在弱爆炸和探测器小视场角的条件下,利用自己研制的多波道仪,在一端开口的Φ200cm×2900cm大型管道里,得到了CH4、空气和煤尘的混合物在不同状态下,特征波长λ等于0.8875、1.000、1.505、2.801和4.346微米(μ)的绝对辐射强度及其有关的变化规律,对结果进行了分析讨论,并与国外实验结果进行了对比,根据测量λ=4.346μ绝对辐射强度和我们选择的黑体辐射模型,获得了爆炸火焰的温度,该项研究不仅在工业中具有重要意义,而且对燃烧和化学动力学的研究也具有参考价值。     

Distributed finite-time coordinated tracking control for multiple Euler–Lagrange systems with input nonlinearity

Nonlinear Dynamics - In this paper, distributed finite-time coordinated tracking control for multiple Euler–Lagrange systems with input nonlinearity is investigated by using backstepping...     

国产优化300／600MW汽轮机通流部分气动设计──第一部分：设计体系与通流设计特点

本文介绍了用于大功率汽轮机通流部分气动设计的准三维／全三维设计体系。使用该设计体系把复合倾斜叶片、可控涡流型等先进的汽轮机气动设计思想，成功地应用到了３００／６００ＭＷ汽轮机的改型设计中，以期较大程度地改进机组的热力性能。     

稀土对NaCl胁迫下矮牵牛幼苗生长抑制的缓解效应

以矮牵牛为材料,采用组织培养的方法,探讨硝酸稀土对NaCl胁迫下矮牵牛幼苗生长抑制的缓解效应.结果表明,在试验区间范围内,采用90 mg·L-1硝酸稀土对0.4%的NaCl胁迫下矮牵牛的株高、单株鲜重和根长有明显的缓解效应,分别为:14.5%,19.9%和53.2%,对生根率缓解效应不明显;当NaCl浓度为0.8%,硝酸稀土对株高和单株鲜重缓解效应不明显,对根长和生根率反而有抑制作用,抑制效应分别达到34.6%和48.4%.在一定范围内硝酸稀土对NaCl胁迫矮牵牛根系的POD,SOD和CAT同工酶的活性均有促进作用,表达种类无明显变化.随着硝酸稀土处理浓度的提高,叶片POD同工酶活性呈现低-高-低变化,表达种类无明显变化;SOD同工酶活性增强,表达种类增多;CAT同工酶活性下降,表达种类减少.