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81.
The changes in mechanical properties, the thermal stability, and the water absorption capacity of poly (vinyl chloride)/olive residue flour composites were studied as a function of various residue olive flour ratios, i.e., 0, 5, 15, and 25% by weight taking into account the effect of benzylation chemical treatment of the filler. The study showed that composite samples prepared with the untreated filler exhibited higher tensile modulus and hardness compared with the neat resin, whereas elongation and tensile strength were observed to decline. On the other hand, the PVC hardness was found to increase with addition of the untreated olive residue flour (ORF), however the composite samples prepared with the benzylated flour exhibited lower hardness than those prepared with untreated olive residue. Moreover, the amount of absorbed water depends on the amount of filler in the composite. The comparison of the results obtained from the samples of F5, F20, and F30 formulations between the untreated and treated ORF indicated a reduction in absorbed water for the composite samples containing treated ORF with benzyl chloride. As a result, the mechanical properties of the treated composites were improved. Furthermore, the thermal characterization of the different samples carried out by color change test and thermogravimetric analysis revealed an increase in the onset temperatures of decomposition for the treated composites. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2008  相似文献   
82.
We have reported an electro‐active paper actuator from regenerated cellulose. After dissolving cellulose fibers with a solution of lithium chloride in N,N‐dimethylacetamide, cellulose was regenerated by combining distillation of cellulose solution along with washing with the mixture of deionized water, isopropyl alcohol, and running water. However, the effect of Li+ ions on structure, properties, and the actuation behavior of the actuator was not studied. This article describes the changes in these parameters when the Li+ ions are removed by subjecting it to different running water exposure time. The structure and properties of cellulose electro‐active paper and its actuation behavior were studied. As Li+ ions content reduced from 4354.17 to 10.26 ppm by increasing the exposure time of running water, crystallinity, Young's modulus, and bending displacement decreased. Details about the investigation have been explained. This elimination of ions is important to increase the piezoelectric effect in EAPap by decreasing the ion migration effect. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci 2008  相似文献   
83.
一个通用代理计费系统开发框架的设计与实现   总被引:4,自引:4,他引:0  
用户在不同的网络环境中选择不同的代理软件实现上网和用户管理,这些代理软件既有共性又各具特色,为减少开发不同代理计费软件的工作量,提高开发效率,加快开发周期,提出利用软件重用的思想,将代理软件的差异集中到少数几个类的实现上,设计并实现一个通用代理计费系统开发框架,基于此框架利用相对简单的步骤开发了基于SQUID的代理计费系统,验证了框架的实用性和可行性,达到了设计目标。  相似文献   
84.
在分析高含水开发单元特点的基础上,针对该阶段剩余油的品位、分布和油水关系极为复杂、挖潜难度大的技术难点,提出了适合江苏复杂断块油田高含水开发单元改善水驱开发效果的思路和工作程序、技术对策,并在真武油田高含水开发单元进行了实际应用,取得了良好的效果.  相似文献   
85.
祝良荣 《微计算机信息》2006,22(14):250-252
热泵热水机组是一种新型热水和供暖产品,它可以从空气、水等环境中吸取能量,热效率高,被公为是传统锅炉、电热水器及燃油(气)热水机组的更新换代环保型产品。详细阐述了以ADμC834芯片为核心的热泵热水机组控制器软硬件系统设计。论述了多路温度数据与压力数据采集、液晶显示等模块的硬件组成及各个模块的工作原理。控制器的软件系统采用前后台架构,用QuickStart平台开发完成。其人机界面系统由按键阵列和TG2401286V2型液晶显示屏组成。  相似文献   
86.
罗坡坝水电站拱坝设置有三个溢流表孔,中间孔高程低于两侧的孔,三个泄水孔设有差动式挑坎。通过模型试验表明,不发生危及岸坡稳定的泄流雾化问题,此外,适当控制泄流水舌射程可以减少坝下冲坑深度,消能效果良好。  相似文献   
87.
BACKGROUND: Over the past several decades methyl tert‐butyl ether (MTBE) as additive to gasoline, intended to either boost ratings of fuel or to reduce air pollution, has been accepted worldwide. Since MTBE has high water solubility, the occurrence of fuel spills or leaks from underground storage tanks or transferring pipeline has led to the contamination of natural waters. In this study the degradation of aqueous MTBE at relatively high concentrations was investigated by a UV‐visible/ZnO/H2O2 photocatalytic process. The effects of important operational parameters such as pH, amount of H2O2, catalyst loading and irradiation time were also investigated. Concentration of MTBE and intermediates such as tert‐butyl formate and tert‐butyl alcohol were measured. RESULTS: Time required for complete degradation increased from 20 to 150 min when the initial concentration was increased from 10 to 500 mg L?1. The first‐order rate constants for degradation of MTBE were estimated to be 0.183–0.022 min?1 as the concentration increased from 10 to 500 mg L?1. Study of the overall mineralization monitored by total organic carbon analysis showed that at an initial concentration of 100 mg L?1 MTBE complete mineralization was obtained after 100 min under UV‐visible/ZnO/H2O2 photocatalysis. CONCLUSION: The data presented in this paper clearly indicated that UV‐visible/ZnO/O2 as an advanced oxidation process provides an efficient treatment alternative for the remediation of MTBE‐contaminated waters. Copyright © 2008 Society of Chemical Industry  相似文献   
88.
Intelligent multisensor surveillance systems consist of several types of sensors, which are installed on fixed and mobile devices. These components provide a huge quantity of information that has to be contrasted, correlated and integrated in order to recognize and react on special situations. These systems work in highly dynamic environments, with severe security and robustness requirements. All these characteristics imply the need for distributed solutions. In these solutions, scattered components can decide and act with some degree of autonomy (for instance, if they become isolated), or cooperate and coordinate for a complete tracking of special situations. In order to cope with these requirements and to better structure the solution, we have decided to design surveillance system control as a multiagent system. This is done by applying an agent-orientated methodology, which is assessed with concrete scenarios.  相似文献   
89.
The aluminium species in different tea infusions were investigated, by determining their stability constants and concentration. This was done for some particular samples using a simple experimental method based on the sorption of aluminium on the strongly sorbing resin Chelex 100, by a batch procedure. From the thermodynamic information obtained it is possible to calculate the concentration of the different species, and in particular that of the free metal ion, which is very important for evaluating the adsorption of aluminium on biological membranes. It was found that aluminium in the tea infusions here considered is present at high total concentration, approximately 0.1 mM, but mainly linked to strong complexes, for instance with side reaction coefficient higher than 10(5.11) at pH 3.95 in one case (tea 1). This could be the reason for the low toxicity of aluminium in tea. These strong complexes were not dissociated even in the presence of Chelex 100. In this case only a limiting value of the reaction coefficient could be evaluated. The presence of the very strong complexes was found in all the tea sample here considered. In two of the considered samples (one black and one green tea) a part of Al(III) was linked to less strong complexes, for example with a reaction coefficient 10(4.14) (tea 2, pH 4.20). The presence in the considered tea infusions of other substances able to complex aluminium was also detected, by the well known ligand titration procedure, at concentration ranging from 0.65 to 3.37 mM in three tea infusions, and at somewhat higher concentration in the case of the ready drink, which was also considered for comparison.  相似文献   
90.
地方热电联产企业发展对策的探讨   总被引:2,自引:2,他引:0  
王武林  夏明 《煤气与热力》2004,24(9):532-534
介绍了泰州热电企业的运行情况,分析了各热电厂在技术改造、扩大热用户和强化内部考核管理方面的措施,探讨了地方热电企业应采取的对策和发展思路。  相似文献   
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