供水管网GIS的开发与维护

以佛山市南海区供水管网信息系统建设为例,详细介绍了GIS的建立,可为拟建供水管网GIS的城市提供参考;介绍了GIS建成后的日常维护,提出在GIS基础数据收集、整理、录入过程中工作流程化管理的重要性.     

Impulse response solution to the three-dimensional vector radiative transfer equation in atmosphere-ocean systems. I. Monte Carlo method

We have developed a powerful 3D Monte Carlo code, as part of the Radiance in a Dynamic Ocean (RaDyO) project, which can compute the complete effective Mueller matrix at any detector position in a completely inhomogeneous turbid medium, in particular, a coupled atmosphere-ocean system. The light source can be either passive or active. If the light source is a beam of light, the effective Mueller matrix can be viewed as the complete impulse response Green matrix for the turbid medium. The impulse response Green matrix gives us an insightful way to see how each region of a turbid medium affects every other region. The present code is validated with the multicomponent approach for a plane-parallel system and the spherical harmonic discrete ordinate method for the 3D scalar radiative transfer system. Furthermore, the impulse response relation for a box-type cloud model is studied. This 3D Monte Carlo code will be used to generate impulse response Green matrices for the atmosphere and ocean, which act as inputs to a hybrid matrix operator-Monte Carlo method. The hybrid matrix operator-Monte Carlo method will be presented in part II of this paper.     

Substrate effect on in-plane dielectric and microwave properties of Ba(Sn0.15Ti0.85)O3 thin films

The microstructure and in-plane dielectric and microwave properties of Barium tin titanate Ba(Sn_0.15Ti_0.85)O₃ (BTS) thin films grown on (1 0 0) LaAlO₃ and (1 0 0) MgO single-crystal substrates through sol–gel process were investigated. X-ray diffraction and field emission scanning electron microscopy were used to characterize crystal structure of phases and microstructure of the thin films, respectively. Microwave properties of the films were measured from 1 to 10 GHz by the interdigital capacitor configuration. The obvious differences in the dielectric and microwave properties are attributed to the stress in the films, which result from the lattice mismatch and difference in the thermal expansion coefficients between the film and substrates. This work clearly reveals the highly promising potential of BTS films for application in tunable microwave devices.     

电泳涂料的国内相关专利分析

文章论述了电泳涂料的机理及组分构成,分析了国内电泳涂料相关专利的分布及发展情况,并对今后发展的方向及趋势进行了展望。     

双层桨搅拌槽内部流场的实验研究

运用计算流体动力学（CFD）方法对双层桨搅拌槽内部流场进行数值模拟。考察了流体在不同桨叶类型、不同桨叶间距对搅拌槽内宏观流动场的影响。研究发现：流体在桨叶间距为150 mm的双层桨内部流场流动效果好。在此间距的基础上得出流体在六圆盘上斜叶桨的搅拌槽内比六圆盘直叶桨搅拌槽内混合效果好。     

盐酸洛哌丁胺的合成及成盐工艺研究

目的:研究盐酸洛哌丁胺、一种用于治疗骨质疏松症药物的关键中间体的制备方法。方法:以2,2-二苯基-γ-丁内酯为起始原料,经开环、SN2取代、酰氯化、季铵化、缩合和成盐制得。结果:当反应温度为25℃,反应时间为24 h,开环和SN2取代的产率为81%。第二步反应,当n(SOCl2):n(2,2-苯基-4-溴丁酸)=2:1、反应温度为回流时,HPLC显示2,2-苯基-4-溴丁酰氯(4)的含量为97.25%。第三步反应,当n(4):n(Na2CO3):n(二甲胺)的投料比为1.0:1.2:1.5,反应温度为0～5℃,关键中间体二甲基-(四氢-3,3-二苯基-2-呋喃叉基)溴化铵(5)的产率由文献报导的50%提高到68%。第四步洛哌丁胺游离碱的制备,较好的投料比为n(7’):n(Na2CO3):n(羟基哌啶)=1.0:1.2:1.1,收率为85%。最后一步成盐,在无水乙醇中调节pH为3左右,收率为89.6%。整个合成步骤(包括精制)的收率为34%,HPLC检测纯度达99.86%。其结构经IR、1H-NMR、13C-NMR和MS表征确认。结论:本制备方法克服了文献所报道的制备工艺的缺点,与现有技术相比,本发明后处理更简单,更适合工业化生产。     

丁基橡胶发展现状及发展建议

2003-2009年我国丁基橡胶需求量平均增长速率超过25%,自给率不到20%。2010年浙江信汇5万t装置投产,在一定程度将缓解市场供需矛盾,但市场缺口依然很大,预计到2014年,国内丁基橡胶总需求量达35万t。文章分析了我国丁基橡胶发展现状并提出了发展建议。     

Synthesis, properties and applications of nanoscale nitrides, borides and carbides

Nanoscale nitrides, borides and carbides are a fascinating type of materials, which have aroused tremendous and continuous research interest for decades owing to their special mechanical, electrical, optical, photoelectronic, catalytic properties and widespread uses. In this feature article, recent developments and breakthroughs in the synthesis, properties and applications of nanometre scale nitrides (BN, Si(3)N(4), GaN, noble nitrides), borides (LnB(6), LnB(2), Fe(3)BO(5), LiMBO(3)) and carbides (carbon, SiC, TiC, NbC, WC) were briefly reviewed in sequence of their different dimensions (1D, 2D and 3D). In particular, our latest advances in the "autoclave route" fabrication of nanoscale nitrides, borides, and carbides were highlighted. The challenges, issues and perspectives of the synthetic methodologies and potential applications concerning the above-mentioned materials were also briefly discussed.     

A Recommendation Approach Based on Bayesian Networks for Clone Refactor

Reusing code fragments by copying and pasting them with or without minor adaptation is a common activity in software development. As a result, software systems often contain sections of code that are very similar, called code clones. Code clones are beneficial in reducing software development costs and development risks. However, recent studies have indicated some negative impacts as a result. In order to effectively manage and utilize the clones, we design an approach for recommending refactoring clones based on a Bayesian network. Firstly, clone codes are detected from the source code. Secondly, the clones that need to be refactored are identified, and the static and evolutions features are extracted to build the feature database. Finally, the Bayesian network classifier is used for training and evaluating the classification results. Based on more than 640 refactor examples of five open source software developed in C, we observe a considerable enhancement. The results show that the accuracy of the approach is larger than 90%. We believe our approach will provide a more accurate and reasonable code refactoring and maintenance advice for software developers.     

基于生态理念的填海用地规划方法探讨

21世纪是海洋经济时代,填海造地逐渐成为人类向海洋拓展生存和发展空间的一种重要手段.填海用地的生态规划方法可以从填海工程中填海成陆的工程步骤层面来探讨,规划的要素包括填海用地的区位选择、填海方式及形态、功能设置和对外交通联系.其中,区位选择应考虑海岸带的综合条件、内侧陆地空间影响和外侧海洋环境影响三个因素;填海方式有接岸式和离岸式,填海用地形态应考虑曲线、小面积、多区块等原则;功能设置应以完善区域发展结构和集约布局为目标,发挥最大经济效益;对外交通设置应采用海底隧道和跨海大桥的方式.