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101.
Combustion tests of pre-mixture of methane and air in constant volume combustion chamber(CVCC) have been carried out by means of flame propagation photo and gas pressure measurement,the effects of CVCC body temperature,intake pressure of pre-mixture of methane and air,equivalence ratio and location of the built-in adaptor have been investigated.The whole combustion chamber can be divided into two parts,i.e.the upper combustion chamber and the lower combustion chamber,by the built-in adaptor with through hol... 相似文献
102.
CHEN KeFan DENG JianHua ZHAO Fei CHENG GuoAn &ZHENG RuiTing Key Laboratory of Beam Technology Material Modification of Ministry of Education College of Nuclear Science Technology Beijing Normal University Beijing China 《中国科学:信息科学(英文版)》2010,(3)
The structures and field emission properties of multi-walled carbon nanotube arrays implanted with Zn+ by MEVVA ion implanter have been investigated.The results revealed that Zn+implantation induced structural damage and that the top of carbon nanotubes with multi-layered graphite structure were transformed into carbon nanowires with amorphous structure.Meanwhile,C:Zn solid solution was synthesized after Zn+ implantation.The turn-on field and threshold field were 0.80 and 1.31 V/μm,respectively for original... 相似文献
103.
依据多体动力学理论,利用Adams的专业模块Adams/Car建立某型号汽车的整车样机模型,探索进行汽车仿真的途径,进行了直线加减速仿真,将仿真结果与试验结果进行了对比,并做了相应的分析. 相似文献
104.
研究了两个混沌系统的有界性及其同步问题,解决了NSG系统和分数阶金融系统的有界性问题,在这两个混沌系统有界的条件下,用线性反馈控制实现有界混沌系统的同步,数值模拟的结果证明了这个方法的有效性. 相似文献
105.
具有区间参数的VRP及其改进的C-W节约算法 总被引:1,自引:0,他引:1
在传统的车辆路径问题的基础上,针对配送中心到客户以及客户到客户之间的费用为区间参数时的车辆路径问题,建立了相应的数学模型.用可能度的区间数排序方法对费用区间参数进行排序并应用到C-W(clark-wright)节约算法中,提出了改进的C-W节约算法.通过算例验证了该算法的有效性和可行性. 相似文献
106.
PENG HongJian WU Qing LI XiaoBo &XIE YouQing School of Chemistry Chemical Engineering Central South University Changsha China School of Material Science Engineering 《中国科学:信息科学(英文版)》2011,(9)
In this paper,taking Nb-Mo alloy system as an example,the equations of concentration of characteristic atoms of alloys in BCC structure were obtained on the basis of the idea of systematic science of alloys and the number of coordination atoms.The concentrations of characteristic atoms in B2-NbMo type ordered alloys were calculated as functions of ordering degree(s) and composition xMo.When s=smax,the concentrations of characteristic atoms of stoichiometric B2-NbMo intermetallic compound are equal to that o... 相似文献
107.
YAO Yu & ZHANG JingZhou College of Energy Power Engineering Nanjing University of Aeronautics Astronautics Nanjing China 《中国科学:信息科学(英文版)》2011,(7)
Experimental and numerical researches were conducted to investigate the cooling performance of a single row of consoles (converging slot-hole) on a large-scale flat-plate model. The results show that the coolant flow from a row of consoles shows good lateral uniformity of adiabatic effectiveness, with regions of slightly enhanced cooling occurring between the consoles. For the console cooling geometry, the interaction between coolant jet from inclined console and the mainstream flow results in reasonable vo... 相似文献
108.
LEI Peng CHANG XiaoLin XIAO Feng ZHANG GuiJin & SU HuaiZhi School of Hydraulic Engineering Changsha University of Science Technology Changsha China College of Water Resources Hydroelectric Engineering Wuhan University.Wuhan Mid-south Design Research Institute China Hydropower Engineering Consulting Group Co Changsha College of Water Conservancy Hydropower Engineering Hohai University Nanjing 《中国科学:信息科学(英文版)》2011,(6)
Owing to the deficiency in early warning for high concrete dam,a formula was established to characterize the deformation behavior of high concrete dam as a whole.The early warning index of spatial deformation was calculated by low probability principle on the basis of the deformation entropy formula proposed.The steps were as follows.Firstly,the probability method was utilized to define the degree of order and degree of chaos for each survey point.Secondly,the weight distribution among the survey points was... 相似文献
109.
ZHANG Tao JIN JunHong HU DaYong YANG ShengLin LI Guang & JIANG JianMing State Key Laboratory for Modification of Chemical Fibers Polymer Materials College of Material Science Engineering Donghua University Shanghai China 《中国科学E辑(英文版)》2009,(4)
The effect of coagulation temperature on the morphology, microstructures and mechanical properties of dihydroxy poly(p-phenylene benzobisoxazole) (DHPBO) fibers was investigated during dry-jet wet- spinning process, in which the coagulation bath concentration and drawn ratio were kept as 10 wt% of PPA in water and 1.7, respectively. The structures and mechanical properties of the as-spun DHPBO fibers were characterized by FTIR, XRD, SEM, and single fiber tensile testing. The results indicated that in PPA/H2... 相似文献
110.
HE ChongJun ZHONG WeiZhuo & LIU YouWen College of Science Nanjing University of Aeronautics Astronautics Nanjing China 《中国科学E辑(英文版)》2009,(6)
Existence of [B3-O6]3- hexagonal ring growth unit in melt solution of β-BaB2O4 crystal was proved by the results of high temperature Raman measurements.A morphology evolution process of β-BaB2O4 crys-tal was observed by a high temperature in-situ observation device.The crystal morphology varied with the supersaturation of growth melt solution.The mechanism of β-BaB2O4 crystal morphology evolution was analyzed through the growth unit model. 相似文献