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61.
盐城市体育馆   总被引:2,自引:0,他引:2  
现代化的综合性体育馆要满足专业性强、布局紧凑、功能多样、节能高效、以馆养馆等多项要求。江苏省盐城市体育馆是第十届全运会的比赛馆之一,赛时使用和赛后利用的兼顾、追求专业性与综合性的统一,是该馆建筑设计的重要内容。  相似文献   
62.
Journal of Applied Electrochemistry - There has been a growing interest in the performance of supercapacitors (SCs) based on Transition Metal Oxides (TMOs). It has recently been included in...  相似文献   
63.
64.
Zhang  Jun  Fang  GuoDong  Yang  LingWei  Li  Wei  Hong  ChangQing  Meng  SongHe 《中国科学:技术科学(英文版)》2020,63(8):1478-1486
It is significant to compare the ablative and compressive mechanical behavior of different PICA-like materials in the engineering applications. The plasma wind tunnel ablation tests with high-entropy air and CO_2 atmospheres, and compressive experiments in the ambient and 150℃, were conducted for three kinds of PICA-like materials(CF/PR-Si, CBCF/PR-SiOC and NQF/PR-Si composites). The traditional carbon/phenolic(C/PR) braided composites were also used for comparison. PICA-like materials have the better thermal insulation than traditional C/PR composite, especially for CBCF/PR-SiOC composite. The ablation behavior of CF/PR-Si and CBCF/PR-SiOC PICA-like materials in the CO_2 atmosphere can produce a large amount of SiO_2 in the form of coatings, oxide layers and skeletons on the ablated surface, which are greatly different from that in the air atmosphere.The compressive behavior of PICA-like material is greatly depended on the fiber fabrics, and exhibits the large discrete characteristics. The longer fiber in the PICA-like materials plays the role in maintaining the material integrity, while it may increase the thermal conductivity.  相似文献   
65.
对水雷声引信系统海上试验的考核方法进行了探讨,重点介绍了战技指标的概念和定义,并针对主要指标要求,分别详细介绍了考核评判标准。  相似文献   
66.
Nano hexahydro-l,3,5-trinitro-l,3,5-triazine (RDX) was prepared using a bi-directional rotation mill and dried under different conditions (liquid, temperature and drying). It shows that the samples cake seriously and the particles grow up obviously by ordinary drying in different liquids at 70 ℃, which occurs again after vacuum drying. With the increase of temperature, the degrees of caking and aggregation are enhanced. Well dispersed sample maintaining constant particle size is extracted by supercritical drying, especially freeze drying. Furthermore, the me- chanical sensitivities of I-RDX, O-RDX and F-RDX, of which the average sizes are 88.03 μm, 15.32 μm and 0.16 μm, respectively, are evaluated. Compared with I-RDX, the friction, impact and shock sensitivities of O-RDX are slightly lower. However, the friction, impact and shock sensitivities of F-RDX are reduced by 30%, 99.0% and 59.9%, respectively.  相似文献   
67.
介绍一种飞机投弹出舱过程自动记录装置。该装置没有对飞机的机械接口和电气接口进行任何改变,只需利用飞机现有挂弹架的挂弹钩接口安装设备,通过光敏开关感应光线强弱变化,判断飞机武器舱门是否打开,从而自动触发高速摄像机拍摄,完成飞机投弹出舱过程的记录任务。  相似文献   
68.
Uniform and beads free fibers of pristine syndiotactic PMMA (s-PMMA), isotactic PMMA (i-PMMA), and their blends in the ratio of s:i = 3:1, 1:1 and 1:3 were successfully prepared using the electrospinning technique. The tactic PMMA blend fibers showed unique thermal stability and glass transition temperatures compared to their pristine counterparts. An interesting endotherm peak was observed for the s:i = 1:3 electrospun fibers, which might indicate a complex formation between the two tactic PMMAs. Systematic surface functionalities study by attenuated total reflectance Fourier transform infrared spectroscopy (ATR-FTIR) revealed the interactions between these two tactic PMMAs. Biocompatibility of tactic PMMA and their blend fibers was first time comparably investigated using HeLa as the model mammalian cell line; an intriguing observance was first revealed that the blend fibers showed better biocompatibility than both pristine ones, though the behind mechanism is not well understood yet.  相似文献   
69.
TiB2 powders were synthesized by borothermal reduction in nanoscale TiO2 with boron under vacuum. Reaction processes were investigated, and the effect of by‐product B2O3 was evaluated. Results showed that TiO2 was firstly reduced by boron to form TiBO3 and Ti2O3, and then to produce TiB2 and B2O3 with increasing temperature. The reaction processes of TiB2 powders synthesis included two‐step reduction in TiO2 by boron and the removal of B2O3. The presence of B2O3, which was previously reported as the most important factor in promoting the coarsening of ZrB2 and HfB2 powders by borothermal reduction, did not lead to significant coarsening of TiB2 powders. Due to the minor effect of B2O3, TiB2 powders with small particle size and low oxygen content could be prepared by direct heat treatment of TiO2 and boron at 1550°C under vacuum for 1 h. The particle size and oxygen content of synthesized TiB2 powders were ~0.9 μm and ~1.7 wt%, respectively.  相似文献   
70.
Platelike α‐Al2O3 powder was obtained at 850°C by thermal decomposition of ammonium aluminum carbonate hydroxide precursor, which was treated by hydrofluoric acid. The results showed the decomposition of the as‐prepared precursors experienced via three steps, adsorption of physical water, dehydration of crystalline water, and decomposition of the precursor, and the activation energies of the above three steps were calculated using the Coats–Redfern method. Meanwhile, the intermediate of (NH4)3AlF6 obtained played an important role in decreasing activation energy of the decomposition and phase transformation. Moreover, the thermal conductivity of the epoxy resin filled with platelike alumina was improved obviously.  相似文献   
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