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31.
介绍了一种基于数控仿型的逆向工程应用系统的组成、原理及应用。  相似文献   
32.
在采矿方案优选的研究中,其决策的正确与否,取决于参与计算的采矿法的定量、定性指标个数以及这些指标的权数。本文通过实例分析了指标权数的波动对采矿方案优劣排序的影响,以减小决策的风险。  相似文献   
33.
The quenching of a SHS sample under conditions of intense heat removal from the outer surface was investigated numerically. A two-step reaction was considered. The reaction proceeds in the reginmes of blending, control, and takeoff. It was established that in the control and takeoff regimes a significant amount of an intermediate phase is fixed during quenching. In the blending regime the relative fraction of the intermediate product in the quenched sample is small. It is shown that the method of quenching with an impacting water jet can be used to investigate phase-and structure-formation processes during SHS.Minsk Translated from Fizika Goreniya i Vzryva, Vol. 28, No. 4, pp. 76–82, July–August, 1992.  相似文献   
34.
原位聚合法研制纳米胶囊相变材料   总被引:2,自引:0,他引:2  
采用超声波工艺及细乳液原位聚合方法,研制了以聚苯乙烯为囊壁、正十八烷为囊芯的纳米胶囊相变材料;系统探讨了聚合反应各因素如引发剂、链转移剂、表面活性剂以及正十八烷/苯乙烯比等对乳胶粒子的形态、胶囊材料热性能的影响,对所研制的胶囊相变材料进行激光衍射粒度分析、透射电镜及差示扫描量热等表征.实验结果表明,在引发剂AIBN 0.5%(油相质量百分比,下同);链转移荆DD在T0.4%;复合乳化剂(SDS/OP10)总量2%,配比1:1及正十八烷/苯乙烯比=1:1条件下,胶囊呈球形均匀分布,聚苯乙烯囊壁能将正十八烷囊芯很好包裹住,其胶囊Z均直径124nm,相变焓可达124.4kJ·kg-1.  相似文献   
35.
匡科 《广东化工》2007,34(3):99-100
《检测和校准实验室能力认可准则》分为l5项管理要素和10项技术要素。作者结合实验室的实际工作,从认可准则管理要求中的组织、管理体系、文件控制、纠正措施、内部审核和管理评审等几个方面有效地推进了实验室质量管理体系的建设,促进实验室的规范化管理。  相似文献   
36.
The influences of the growing process of sulfate-reducing bacteria (SRB) in seawater system on the medium state and corrosion behavior of carbon steel were studied by detecting solution state parameters and using corrosion electrochemical methods. The growing process of SRB in the seawater shows the three stages of growing, death and residual phases. The solution state parameters of the concentration of sulfide, the pH value and the redox potential changed during the three stages of the SRB growing process. And the corrosion rate of D36 carbon steel was accelerated during the growing phase and stable during the death and residual phases. The results indicate that the medium state and the corrosion rate of the steel do not depend on the number of active SRB, but depend on the accumulation of the metabolism products of SRB.  相似文献   
37.
The thermal degradation of poly(vinyl butyral) (PVB)/glass ceramic, PVB/Ag, and PVB/glass ceramic/Ag composites was investigated with thermogravimetric analysis in nitrogen and air. Thermogravimetric data revealed that the compositions of both inorganic materials in air could greatly influence the thermal degradation of PVB. The degradation reactions of PVB/ceramic and PVB/Ag composites began earlier and accelerated rapidly at lower temperatures. The overall degradation period was obviously shortened for the thermal degradation of PVB/Ag in air, whereas a longer time was required for the PVB/ceramic composite than for PVB. Moreover, dual effects of ceramic and Ag on the thermal degradation of PVB were observed for PVB/ceramic/Ag composites. In addition, the catalytic effects of ceramic and Ag on the degradation reaction of PVB in air were verified with a kinetic analysis. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 93: 2142–2149, 2004  相似文献   
38.
Cloud computing techniques take the form of distributed computing by utilizing multiple computers to execute computing simultaneously on the service side. To process the increasing quantity of multimedia data, numerous large-scale multimedia data storage computing techniques in the cloud computing have been developed. Of all the techniques, Hadoop plays a key role in the cloud computing. Hadoop, a computing cluster formed by low-priced hardware, can conduct the parallel computing of petabytes of multimedia data. Hadoop features high-reliability, high-efficiency, and high-scalability. The numerous large-scale multimedia data computing techniques include not only the key core techniques, Hadoop and MapReduce, but also the data collection techniques, such as File Transfer Protocol and Flume. In addition, distributed system configuration allocation, automatic installation, and monitoring platform building and management techniques are all included. As a result, only with the integration of all the techniques, a reliable large-scale multimedia data platform can be offered. In this paper, we introduce how cloud computing can make a breakthrough by proposing a multimedia social network dataset on Hadoop platform and implementing a prototype version. Detailed specifications and design issues are discussed as well. An important finding of this article is that we can save more time if we conduct the multimedia social networking analysis using Cloud Hadoop Platform rather than using a single computer. The advantages of cloud computing over the traditional data processing practices are fully demonstrated in this article. The applicable framework designs and the tools available for the large-scale data processing are also proposed. We show the experimental multimedia data including data sizes and processing time.  相似文献   
39.
20%磷威乳油(沅化938)是一种以有机磷、氨基甲酸酯类农药为有效成分的新的混配制剂,在防治棉蚜、棉铃虫、棉叶螨等方面的增效作用十分显著。它有击倒快、触杀作用强、广谱等特点。该乳油配方先进,独特,系国内首创。生产工艺简单,易于操作,产品性能稳定。  相似文献   
40.
结合雅砻江流域实际预报情况,从资料误差,包括雨量、实测流量、蒸发量、入库流量、出库流量;人类活动影响;汇流计算;自动预报等方面,分析了雅砻江流域洪水预报的误差原因,给出了相应的改进建议。  相似文献   
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