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131.
赵金 《数码设计:surface》2014,(9):83-85
广府和潮汕同是岭南文化的主体,但又都是独立的文化分支,在建筑及其装饰上也各有特色和侧重。文章就岭南传统建筑中广府地区的陶塑装饰和潮汕地区的嵌瓷装饰予以介绍并比较,找出区别与文化间的共通处,并希望在当下社会语境中这些传统建筑装饰能被更多人重新审视。 相似文献
132.
Ying Quan Mingshan Yang Tongxiang Liang Qin Yan Deshan Liu Riguang Jin 《应用聚合物科学杂志》2007,103(6):3940-3949
Novel composite particles based on nanoscale calcium carbonate (nano‐CaCO3) as the core and polyacrylates as the shell were first synthesized by in situ encapsulating emulsion polymerization in the presence of the fresh slush pulp of calcium carbonate (CaCO3) nanoparticles. Subsequently, these modified nanoparticles were compounded with rigid poly(vinyl chloride) (RPVC) to prepare RPVC/CaCO3 nanocomposites. At the same time, the effects of the reinforcement and toughening of these modified nanoparticles on RPVC were investigated, and the synergistic effect of modified nanoparticles with chlorinated polyethylene (CPE) was also studied. The results showed that in the presence of nano‐CaCO3 particles, the in situ emulsion polymerization of acrylates was carried out smoothly, and polyacrylates successfully encapsulated on the surface of nano‐CaCO3 to prepare the modified nanoparticles, breaking down nano‐CaCO3 particle agglomerates, improving their dispersion in the matrix, and also increasing the particle–matrix interfacial adhesion. Thus, the effects of the reinforcement and toughening of these modified nanoparticles on RPVC were very significant, and the cooperative effect of the nanoparticles with CPE occurred in the united modification system. Scanning electron microscopy analyses indicated that large‐fiber drawing and network morphologies coexisted in the system of joint modification of nanoparticles with CPE. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 103: 3940–3949, 2007 相似文献
133.
针对特征模型的演化导致特征间的冲突问题, 从特征模型的演化方面进行研究, 提出了一种基于本体的特征模型演化的一致性验证方法。首先采用本体理论方法对特征模型的演化进行分析和建模, 建立本体的特征模型元模型; 其次基于上述元模型, 为网上购物系统实例建立相应的网上购物的领域特征模型, 根据需求裁剪出产品特征模型; 然后在Eclipse集成开发环境下, 通过Jena推理机加载规则和产品特征模型进行一致性验证, 当检测到冲突时, 采用演化策略来消除冲突; 最后通过实例研究说明了该方法的有效性。 相似文献
134.
在RFID定位算法中,利用接收信号强度统计模型进行直接定位的精确度不高,而利用实际参考标签定位存在信号易碰撞、外出部署不便等问题,因此提出一种基于虚拟标签的RFID定位算法VIREH以克服以上缺点.该算法利用历史数据构建虚拟参考标签,然后利用虚拟参考标签代替实际参考标签进行定位.依据VIREH算法,开发基于Android移动设备的RFID定位系统,在系统中使用VIREH算法进行定位,对定位误差进行了统计以测试算法性能.测试结果表明,VIREH算法的定位精度较直接定位有显著提高,较使用实际参考标签没有明显降低,有助于提高RFID定位精度. 相似文献
135.
Yuxin Yin Zhengguo Jin Feng Hou Xu Wang 《Journal of the American Ceramic Society》2007,90(8):2384-2389
Titanium dioxide (TiO2 ) nanotube arrays were prepared by electrochemical anodization of titanium sheets in the glycerol 176 mL/H2 O 44 mL/NH4 F 0.5 wt% electrolytes modified with H2 SO4 and NaAc addition. The surface morphologies, average inner diameter, and the length of the nanotube arrays changed with the solution pH in the range from 5.6 to 4.0 by adding H2 SO4 . A uniform surface morphology of the nanotubes with average inner diameter of ∼80 nm and a length of ∼1000 nm was obtained when the solution pH was 5.0. The growth rates of the nanotubes were remarkably enhanced by NaAc addition in the range of 0.04–0.14 M . With NaAc addition of 0.10 M , the length of the nanotube arrays reached 4.16 μm after an 8-h anodization, increasing 3.23 μm compared with no NaAc addition. The relationship between solution pH and growth of TiO2 nanotubes was analyzed by current–time curves, solution electrical conductivities, and scanning electron microscopy (SEM), and the role of NaAc was also discussed based on SEM and solution electrical conductivities. 相似文献
136.
随着无线传感器网络的发展,无线网络数据采集节点的低功耗要求也不断提高。针对这一要求,利用内部集成了射频模块的CC430F5137设计并实现了一种低功耗无线数据采集节点。利用无线模块唤醒功能降低了系统功耗,同时根据载波监听功能改进了射频发送函数,提高了抗干扰能力。实验结果表明,该设计的低功耗和抗干扰方法是可行的。 相似文献
137.
A mathematical model of fluid flow and mass transfer in a packed bed was derived and used to evaluate the liquid phase axial dispersion and mass transfer coefficients under high pressure conditions. The least-squares method was used to evaluate the rate parameters from experimental breakthrough curves, and the agreement between the concentration curves predicted from rate parameters and those measured experimentally was good. Experiments were performed at 20 and 200°C with water as a solvent and nonporous soda-lime glass beads as packing. Although the axial dispersion coefficient was independent of temperature and pressure, the mass transport parameters were found to be pressure dependent. 相似文献
138.
Summary The chemical process of preparing poly(vinylchloride)-polypyrrole composite films with high electrical conductivity and transparency has been studied. Pyrrole has been diffused into the poly(vinylchloride) matrix in the swelling medium of n-hexane and acetone mixture. The oxidative polymerization of the diffused pyrrole in the binary solvent system of acetonitrile and methanol gives high conductivity of the polypyrrole as well as the good penetration of the oxidant into the PVC polymer matrix. The analytical testing of the composite film shows the formation of homogeneous mixture of polypyrrole and poly(vinylchloride) conductive layer within the 1.0m of thickness on the film surface. The transparency of the composite film showed about 50–60% at 500 nm. The electrical conductivity of the composite was about 20 s/cm. 相似文献
139.
Given the conditions of residual coal from the boundary of a flat dipping open-pit mine,which uses strip areas mining and inner dumping with slope-covering,we propose an open-pit and underground integrated mining technology for residual coal of end slopes.In the proposal a conveyance road and ventilation conveyance near the slope are built,corresponding to the pit mining area and the surface coal mine dump,as well as an interval haulage tunnel and air-inlet tunnel.The outcome shows that such mining method may reduce the effect to slope stability from underground mining,it does not affect the dumping advance and has a high recovery rate of residual coal resources.The working face is timbered by single hydraulic props,transported by a scraper conveyor and supported by coal walls.This method of mining is one of layered top coal caving,with high resource recovery,low production cost where positive economic benefit can be realized. 相似文献
140.
针对普通电火花成型机床在进行较深的小孔加工时存在的问题,对电火花成型机床进行部分改造,增加一个压力循环系统,使工具电极中喷出高压工作液,使之更适应小孔加工的条件.以DMKT132精密数控电火花成型机床的改造为实例,说明机床改造前后加工小孔的变化,结果表明,用该方法加工小孔,加工效率平均提高一倍以上,提高了加工质量,具有广泛的推广价值. 相似文献