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961.
962.
铅壳柔爆索冲量作用下圆柱壳体结构响应实验研究   总被引:4,自引:0,他引:4  
通过设计排布在圆柱壳体周围的柔爆索的间距及柔爆索与圆柱壳体间的距离 ,得到了沿圆柱壳体周向呈余弦分布的冲量载荷 ,并设计了柔爆索加载的结构响应实验装置 ,对圆柱壳体的动态力学响应进行了实验研究。测得的圆柱壳体残余变形局限于 70左右的范围 ,0方向径向变形最大。  相似文献   
963.
This paper is concerned with membrane analysis and optimal design of submerged domes. In addition to hydrostatic pressure, domes are also subjected to selfweight and skin cover load, which are invariably present in these types of structures. Using the membrane theory for thin shells and by adopting a fully stressed design, equations governing the meridional curve of submerged domes are derived with allowance for selfweight and skin cover load. A set of nonlinear differential equations, which correspond to a two-point boundary problem, is solved by the shooting-optimization method. Based on a family of fully stressed designs associated with a given water depth and dome height, the optimal dome shape for minimum weight is determined.  相似文献   
964.
Chai  Young S.  Argatov  Ivan I. 《Meccanica》2018,53(11-12):3137-3143
Meccanica - A three-dimensional contact between two linear elastically similar transversely isotropic solids of arbitrary geometry is considered. A simplified version of the classic...  相似文献   
965.
Wang  Xuegang  Liu  Yajie  Sun  Zhanxue  Li  Jiang  Chai  Liyuan  Min  Xiaobo  Guo  Yadan  Li  Peng  Zhou  Zhongkui 《Journal of Radioanalytical and Nuclear Chemistry》2017,314(1):251-258
Journal of Radioanalytical and Nuclear Chemistry - We evaluated uranium bioleaching from low-grade, granite-type uranium ore using mixed acidophilic microbes from uranium mine leachate. A 4854-ton...  相似文献   
966.
The development of the uranyl cation as a powerful photocatalyst is seriously delayed in comparison with the advances in its fundamental and structural chemistry. However, its characteristic high oxidative capability in the excited state ([UO2]2+* (+2.6 V vs. SHE; SHE=standard hydrogen electrode) combined with blue-light absorption (hv=380 – 500 nm) and a long-lived fluorescence lifetime up to microseconds have reveals that the uranyl cation approaches an ideal photocatalyst for visible-light-driven organic transformations. Described herein is the successful use of uranyl nitrate as a photocatalyst to enable C(sp3)−H activation and C−C bond formation through hydrogen atom transfer (HAT) under blue-light irradiation. In particular, this operationally simple strategy provides an appropriate approach to the synthesis of diverse and valuable diarylmethane motifs. Mechanistic studies and DFT calculations have provided insights into the detailed mechanism of the photoinduced HAT pathway. This research suggests a general platform that could popularize promising uranyl photocatalytic performance.  相似文献   
967.
Bi  Xi  Bai  Ping  Yang  Ting  Zhang  Jingyu  Li  Hui  Chai  Zhanli  Wang  Xiaojing 《Journal of Solid State Electrochemistry》2020,24(7):1567-1575
Journal of Solid State Electrochemistry - Metal oxide is a promising anode material in LIBs, which can be further improved by covering with few-layered graphene oxide (FL-rGO). Furthermore, the...  相似文献   
968.
Fitch DM  Evans KA  Chai D  Duffy KJ 《Organic letters》2005,7(24):5521-5524
[reaction: see text] An efficient two-pot, asymmetric synthesis of benzothiadiazine-substituted tetramic acids is reported. Starting from commercially available alpha-amino acids or esters, reductive amination followed by a novel one-pot amide bond formation/Dieckmann cyclization provided the desired products in high yield and optical purity. An analogous solid-phase approach to the same targets is also presented. These compounds were found to be potent inhibitors of hepatitis C virus RNA-dependent RNA polymerase.  相似文献   
969.
The influences of ultrasonic output intensity, solution pH, H2O2 concentration and the addition of Fenton reagent on the degradation of 2,4-dinitrophenol (DNP) under ultrasonic irradiation were investigated. It was observed that the degradation of DNP fitted pseudo-first-order dynamics under our experimental conditions. Increasing the ultrasonic output intensity increased the degradation efficiency of DNP and low pH favored the ultrasonic degradation of DNP. The addition of H2O2 enhanced the ultrasonic degradation efficiency of DNP. The further addition of Cu2+, however, hindered the degradation of DNP. In contrast, sono-oxidation treatment in combination with FeSO4/H2O2 showed a synergistic effect for DNP degradation.  相似文献   
970.
This Letter describes the measurement of the energy dependence of elliptic flow for charged particles in Au+Au collisions using the PHOBOS detector at the Relativistic Heavy Ion Collider. Data taken at collision energies of square root of s(NN)=19.6, 62.4, 130, and 200 GeV are shown over a wide range in pseudorapidity. These results, when plotted as a function of eta(')=|eta|-y(beam), scale with approximate linearity throughout eta('), implying no sharp changes in the dynamics of particle production as a function of pseudorapidity or increasing beam energy.  相似文献   
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