关于测绘档案管理的几点思考

本文首先总结和归纳了在信息化时代测绘档案管理的现状。提出了档案管理工作中存在的资料不全,管理手段落后,存储设施不足以及管理无章可循等问题。并提出了应对措施。     

An addendum to “Numerical modeling of an enhanced very earlytime electromagnetic (VETEM) prototype system”

For original paper see Cui et al. (IEEE Antennas and Propagation Magazine, vol.42, no.2, p.17-27, 2000 April). Cui et al. proposed two numerical models to simulate an enhanced very early time electromagnetic (VETEM) prototype system, used for buried-object detection and environmental problems. In the first model, the transmitting and receiving loop antennas were accurately analyzed using the method of moments (MoM), and then conjugate gradient (CG) methods with the fast Fourier transform (FFT) were utilized to investigate the scattering from buried conducting plates. In the second model, two magnetic dipoles were used to replace the transmitter and receiver, because the working frequency for the VETEM system is usually low. Both the theory and formulation were correct, and the simulation results for the primary magnetic field and the reflected magnetic field were accurate. We have compared the simulation results for the magnetic field reflected by a wire-conductor mesh on the ground with measured data. They fit very well. However, the scattered magnetic fields in the simulation results were inaccurate, because we did not use a sufficient number of iterations in the CG-FFT algorithm when the frequency was very low     

氢化丁腈橡胶的回收利用

研究了机械薄通法回收硫化氢化丁腈橡胶(HNBR)的工艺对其性能的影响以及回收胶在HNBR密封制品中的掺用效果。结果表明,通过适当机械薄通回收工艺制得的硫化HNBR回收胶可以并用到正常HNBR胶料中,并用量在10~50质量份;较好的薄通回收工艺条件为:辊温60~80℃,辊距和薄通次数分别为0.3mm和10~20次或0.5mm和20~30次。     

An associated elastic–viscoplastic constitutive model for sandstone involving shear-induced volumetric deformation

In contrast to hard rocks, weak rocks often have significant shear-induced volumetric contraction/dilation under short-term or long-term loadings, and this behavior necessitates the development of an unconventional constitutive model. As such, an elastic–viscoplastic constitutive model characterizing the mechanical behavior of weak rocks is proposed, and its validity is demonstrated by comparing the simulated and the actual deformational behaviors of weak sandstone under various stress paths. In order to distinguish the immediate and the time-dependent deformation, the procedures involving multi-stage loading–unloading and creep tests, together with controlled pure-shear stress path, have been undertaken to clarify the deformation behavior of sandstone. Through these experimental procedures, elastic and viscoplastic deformations can be effectively separated, and the coupling between shear stresses and volume stresses can also be identified. Consequently, it is found that the function form of yield surfaces can also be applied to plastic potentials and viscoplastic potentials so that the complexity of the constitutive model to be developed is significantly reduced. Furthermore, the parameters for the proposed constitutive model can be readily obtained by fitting experimental data. Through systematic comparisons of the predictions and the actual behaviors of the studied sandstone, it is found the proposed constitutive model is capable of describing the elastic, plastic, and viscoplastic deformational behaviors not only under pure shearing stress path that were used to calibrate parameters, but also under other stress paths.     

工程造价文件编制的几点心得

1 加强专业知识学习,提高自身业务素质 工程造价文件的编制工作是一项政策性、经济性、技术性和专业性很强的工作,造价文件编制质量的优劣直接反映了设计单位的整体水平.因此,无论是工程设计人员,还是工程造价人员,都应重视工程造价方面知识的学习和积累,及时了解国家及省市的各项有关法律法规、相关知识,学习掌握各专业知识,熟悉施工工艺,定期参加各种专业的培训学习,掌握学习我国就WTO达成双边协议工程咨询技术、法规、管理体系及发展方向.     

从直觉走向形式——宁波市游泳健身中心

通过分析宁波市游泳健身中心的个性创作过程——从直觉走向形式,指出一般建筑的个性创造不是追求形式主义,只有深刻地体会功能和形式之间的有机统一关系,才能正确地把握建筑的个性创造。     

演艺灯光设计中应防三大危险

指出了演艺灯光设计中在电气系统、防火和建筑防塌方面存在的隐患,对供电可靠性、变压器的连接组别、谐波、静电、防雷、配电设备的选择、线路敷设、主舞台及观众厅火灾探测器的选择和安装等问题进行论述.     

A preliminary evaluation of a continuous‐flow reactor for liquid–liquid–solid phase‐transfer catalyzed synthesis of n‐butyl phenyl ether

This study evaluates the feasibility of using a continuous‐flow stirred vessel reactor (CFSVR) to synthesize n‐butyl phenyl ether (ROPh) from n‐butyl bromide (RBr) and sodium phenolate (NaOPh) by liquid–liquid–solid phase‐transfer catalysis (triphase catalysis). The factors affecting the preparation of triphase catalysts, the etherification reaction in a batch reactor, and the performance in a CFSVR were investigated. The kinetic study with a batch reactor indicated that when the initial concentration of NaOPh or RBr was high, the conversion of RBr would depend on the initial concentration of both RBr and NaOPh. The reaction can be represented by a pseudo‐first‐order kinetic model when the concentration of NaOPh is in proper excess to that of RBr, and the apparent activation energy is 87.8 kJ mol^?1. When the etherification reaction was carried out in the CFSVR, the catalyst particles did not flow out of the reactor, even at a high agitation speed. The conversion of RBr in the CFSVR was, as predicted, lower than that in the batch reactor, but was higher than the theoretical value because the dispersed phase is not completely mixed. Copyright © 2004 Society of Chemical Industry