N-联芳基酰胺类化合物的合成与杀菌活性研究

应用Suzuki偶联反应和缩合反应合成了8个结构新颖的N-联芳基酰胺类化合物,其结构经1HNMR、GC-MS进行了确证。初步杀菌活性研究结果表明所设计并合成的化合物具有一定的杀菌活性,如化合物9f和9g在500 mg/L剂量下,对小麦白粉病具有80%以上的防治效果;化合物9h在25 mg/L剂量下,对油菜菌核病菌的抑制活性达70%以上。     

Bonding characteristics and corrosion resistance of silane–cerium-treated aluminum adherend

A silane–cerium treatment was applied on an aluminum adherend to simultaneously improve the bonding performance and corrosion resistance of the adhesively bonded aluminum joint in cryogenic applications, such as with liquefied natural gas containment tanks. The lap shear strengths and corrosion performances of the adhesively bonded joints composed of treated aluminum adherends were measured with respect to the silane–cerium treatment and the surface pretreatment on the aluminum adherend. The bonding characteristics of the aluminum adherend were investigated by measuring the water contact angle and conducting the potentiodynamic polarization test after the aluminum adherends with different surface treatments of silane–cerium were immersed in a 0.5?M NaCl solution. In addition, the surfaces were analyzed with scanning electron microscopy, X-ray photoelectron spectroscopy, and Fourier transform infrared spectroscopy to characterize the chemical compositions of the silane–cerium-treated aluminum adherend. The experimental results show that an appropriate silane–cerium treatment on the aluminum adherend produces an effective corrosion-resistant layer and that it has a highly reliable bonding characteristic for the adhesive joint at a cryogenic temperature of ?150?°C.     

An efficient fluid-solid coupled finite element scheme for weapon fragmentation simulations

An efficient finite element (FE) scheme to deal with a class of coupled fluid-solid problems is presented. The main ingredients of such methodology are: an accurate Q1/P0 solid element (trilinear in velocities and constant piecewise-discontinuous pressures); a large deformation plasticity model; an algorithm to deal with material failure, cracking propagation and fragment formation; and a fragment rigidization methodology to avoid the possible numerical instabilities that may produce pieces of material flying away from the main solid body. All the mentioned schemes have been fully parallelized and coupled using a loose-embedded procedure with a well-established and validated computational fluid dynamics (CFD) code (FEFLO). A CSD and a CFD/CSD coupled case are presented and analyzed.     

用插值法确定长距离输送机液力偶合器控制特性曲线

论述了采用调速型液力偶合器驱动装置可以满足长距离输送机的各项要求以及如何利用计算机插值方法确定所要求的调速型液力锅台控制特性曲线。     

Brief bimanual force pulses: Correlations between the hands in force and time.

Three experiments assessed coupling phenomena in the coordination of bimanual force pulses. Experiment 1 required symmetric force pulses (equal target forces and rise times for both hands) using the index finger of each hand. As the authors expected, on the basis of bimanual pointing movement results, this experiment revealed positive correlations between both the force rise times and the force amplitudes of the two hands. Experiments 2 and 3 included asymmetric conditions with different target force amplitudes (Experiment 2) or target rise times (Experiment 3). In Experiment 2 force amplitudes but not rise times were fully decoupled in the asymmetric condition. In the asymmetric condition of Experiment 3, however, neither rise times nor force amplitudes were fully decoupled. The results suggest a hierarchical control structure with temporal control dominating nontemporal control of bimanual force coordination. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

基于RELAP5和FLUENT的多尺度耦合分析方法研究

基于二次开发得到的铅冷快堆一维系统程序RELAP5_LEAD和三维计算流体力学程序FLUENT，利用动态链接库技术和FLUENT用户自定义函数，开发了多尺度耦合分析程序RELAP5/FLUENT。在单相范围内，分别利用耦合程序RELAP5/FLUENT开展简单铅冷串联管道的瞬态流动和传热模拟、简单铅冷闭式回路的瞬态流动模拟，并与RELAP5_LEAD计算结果开展Code-to-Code对比分析。研究结果表明，RELAP5/FLUENT计算结果与RELAP5_LEAD模拟结果吻合良好，耦合程序的开发取得了初步成功，可用于分析铅冷快堆堆内的复杂三维热工水力现象。     

Modification of waste silicas by silanes and titanates and their use as reinforcing fillers in elastomer composites

Results on the use of waste silica, a by-product in the production of aluminum fluoride, as an elastomer filler are presented. Modification of the purified silica surface with silane and titanate coupling agents has been carried out. The effect of the type and amount of modifying agent on the physico-mechanical properties in vulcanizates of butadiene-styrene rubber and in polyurethane elastomers has been tested. The mechanical properties of butadiene-styrene rubber vulcanizates filled with waste silica show that the most favorable modifying effect is shown by mercaptosilanes A-189 and A-1893, polysulfide Si-69, and titanate KRTTS, as indicated by increased strength parameters. However, testing of the mechanical properties in polyurethane elastomers filled with waste silica has demonstrated that silica modification with aminosilanes A-1100 and A-1120 yield polyurethane compositions of optimum strength parameters.     

Centered inclined slot coupling between waveguides with coplanar axes

The article presents the method of finding the complete equivalent circuit of two waveguides with coplanar axes coupled through a centered inclined slot in the common broad wall. The variational method based on dyadic Green's function is used for finding the parameters of the equivalent circuit. A cosinusoidal aperture field distribution is assumed. Considerable mathematical simplification is resulted from replacing the centered inclined slot by an equivalent magnetic dipole. Coupling slot characteristics are deduced, including resonant length, dominant mode scattering in both the waveguides. Numerical and experimental results for resonant lengths and scattering parameters are presented over a range of tilt angles, frequencies, and waveguide dimensions. These results have significant applications in linear waveguide arrays and coupler design. © 2010 Wiley Periodicals, Inc. Int J RF and Microwave CAE, 2011.     

Lithium-doped sulfated-zirconia catalysts for oxidative coupling of methane to give ethylene and ethane

Li-doped sulfated-zirconia catalysts were found to be effective for oxidative coupling of methane (OCM). The catalyst performances depend on the sulfate content and calcination temperature. A maximum C₂ yield is attained over the catalysts, which contain 6 wt.% sulfate and calcined at 923–973 K, being closely related to the preparation conditions of sulfated-ZrO₂ as solid super-acids. When the performances of the Li-doped sulfated-ZrO₂ (Li/SZ) catalysts were tested at 1023 K as a function of reaction time, both the C₂ and CO_x selectivities remained constant over the range of 8 h, but the CH₄ conversion decreased from 17.5% to 11.9%. The nature of Li/SZ catalysts for the OCM was investigated by X-ray diffraction, XPS, and NH₃ and CO₂ TPD measurements. It could be postulated that the sulfated-ZrO₂ surface could play an important role in the formation of a catalytically active structure by Li-doping.     

并联双线圈式直流接触器电磁机构合闸动作特性研究

直流接触器是新能源系统以及电动汽车中配置最为广泛的开关电器之一。而直流接触器的动态特性是衡量直流接触器性能的重要指标之一。本文以并联双线圈式直流接触器为研究对象，建立了直流接触器电磁机构的动力学模型，利用基于Adams与Maxwell的联合仿真研究方法对直流接触器的电磁机构进行合闸过程的仿真分析，研究结果表明，机构合闸动作的仿真合闸时间与试验合闸时间相吻合，验证了该仿真方法的正确性；同时研究了弹簧参数和线圈参数等因素对机构合闸运动特性的影响，研究发现在一定范围内弹簧预压力变化对合闸时间影响不大，线圈安匝数增大会导致合闸时间变小，线圈内阻增大会导致合闸时间变大且动触头弹跳更剧烈。本文的仿真方法与结果能为直流接触器电磁机构的改进设计与优化提供一定参考。