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803.
准噶尔盆地东北缘卡拉麦里地区是我国重要的金矿分布区,区内断裂系统错综复杂,控矿作用显著,需对不同方位、不同规模断裂系统的空间分布规律、发育复杂程度及对金矿床的控制规律进行深入研究,目前尚未见对该区域断裂系统的分形特征与金矿分布关系研究。对准噶尔盆地东北缘卡拉麦里地区断裂构造进行了不同尺度、不同方位的分形维数计算,得到全部断裂构造的分形维数为1.421,各方向断裂构造的分形维数:NW向为1.382,NWW向为1.223,近EW向为0.976,NE向为0.960;全部断裂构造和NW向断裂构造的分形维数均大于能反映地质体连通性的分形维数临界值(1.22~1.38)。结果表明,东准噶尔卡拉麦里地区的地质体具有较高的连通性,为金成矿热液提供了有利的运移通道和汇聚场所,NW向断裂构造发育最复杂,为研究区主导性导矿构造,对金矿的形成具有控制作用;这与研究区绝大部分金矿床(点)主要沿卡拉麦里深大断裂和清水—苏吉泉深大断裂派生的NW至NWW向断裂展布的特征相吻合。 相似文献
804.
压剪复合平板冲击加载技术进展及其应用 总被引:1,自引:0,他引:1
自20世纪70年代末发明压剪炮以来, 压剪复合冲击加载实验技术和诊断技术有了长足进展, 应用也日益广泛.由于压剪联合加载波直接反映了材料的动态剪切特性, 对于认识材料的屈服、损伤演化、失效、相变、界面滑移等动态行为和机理, 构筑更全面的本构模型能够提供必要的附加信息.本文主要讨论气炮实验中压剪复合应力波的产生方式, 诊断技术, 以及在压剪复合塑性波和动高压本构模型、聚合物压剪冲击行为、剪切波跟踪法(SWT)和水泥基复合材料的损伤和失效、界面动摩擦行为、冲击相变、动态损伤和断裂等方面的研究与应用进展. 相似文献
805.
PARALLEL COMPUTING FOR STATIC RESPONSE ANALYSIS OF STRUCTURES WITH UNCERTAIN-BUT-BOUNDED PARAMETERS 总被引:2,自引:0,他引:2
The vertex solution for estimation on the static displacement bounds of structures with uncertain-but-bounded parameters is studied in this paper. For the linear static problem, when there are uncertain interval parameters in the stiffness matrix and the vector of applied forces, the static response may be an interval. Based on the interval operations, the interval solution obtained by the vertex solution is more accurate and more credible than other methods (such as the perturbation method). However, the vertex solution method by traditional serial computing usually needs large computational efforts, especially for large structures. In order to avoid its disadvantages of large calculation and much runtime, its parallel computing which can be used in large-scale computing is presented in this paper. Two kinds of parallel computing algorithms are proposed based on the vertex solution. The parallel computing will solve many interval problems which cannot be resolved by traditional interval analysis methods. 相似文献
806.
Ruyun Yue Fang Xia Ruijuan Qi Da Tie Shanshan Shi Zhiping Li Yufeng Zhao Jiujun Zhang 《中国化学快报》2021,32(2):849-853
The P2-type manganese-based Na_(0.7)MnO_2 cathode materials attract great interest due to their high theoretical capacity.However,these materials suffer from rapid capacity fading,poor rate performance and severe voltage decay resulting from phase transition and sluggish reaction kinetics.In this work we report a novel Nb-doped Na_(0.7) [Ni_(0.3)Co_(0.1)Mn_(0.6)]_(1-x)Nb_xO_2 with significantly suppre ssed voltage decay and enhanced cycling stability.The strong Nb-O bond can efficiently stabilize the TMO fra mework,and the as prepared material demonstrates much lower discharge midpoint voltage decay(0.132 V) than that of pristine one(0.319 V) after 200 cycles.Consequently,a remarkably improved cycling perfo rmance with a capacity retention of 87.9% after 200 cycle at 0.5 C is achieved,showing a 2.4 fold improvement as compared to the control sample Na_(0.7)Ni_(0.3)Co_(0.1)Mn_(0.6)O_2(~37% rotation).Even at 2 C,a capacity retention of 68.4% is retained after 500 cycles.Remarkably,the as prepared material can be applied at low temperature of-20℃,showing a capacity retention of 81% as compared to that at room temperature. 相似文献
807.
Fayan Li Yanyan Li Lei Li Wen Luo Zhouguang Lu Xinyu Zhang Zhiping Zheng 《Chemical science》2022,13(32):9256
Hydrogen production technology by water splitting has been heralded as an effective means to alleviate the envisioned energy crisis. However, the overall efficiency of water splitting is limited by the effectiveness of the anodic oxygen evolution reaction (OER) due to the high energy barrier of the 4e− process. The key to addressing this challenge is the development of high-performing catalysts. Transition-metal hydroxides with high intrinsic activity and stability have been widely studied for this purpose. Herein, we report a gelatin-induced structure-directing strategy for the preparation of a butterfly-like FeNi/Ni heterostructure (FeNi/Ni HS) with excellent catalytic performance. The electronic interactions between Ni2+ and Fe3+ are evident both in the mixed-metal “torso” region and at the “torso/wing” interface with increasing Ni3+ as a result of electron transfer from Ni2+ to Fe3+ mediated by the oxo bridge. The amount of Ni3+ also increases in the “wings”, which is believed to be a consequence of charge balancing between Ni and O ions due to the presence of Ni vacancies upon formation of the heterostructure. The high-valence Ni3+ with enhanced Lewis acidity helps strengthen the binding with OH− to afford oxygen-containing intermediates, thus accelerating the OER process. Direct evidence of FeNi/Ni HS facilitating the formation of the Ni–OOH intermediate was provided by in situ Raman studies; the intermediate was produced at lower oxidation potentials than when Ni2(CO3)(OH)2 was used as the reference. The Co congener (FeCo/Co HS), prepared in a similar fashion, also showed excellent catalytic performance.A butterfly-like FeNi/Ni HS featuring a “torso” of Ni-doped FeOOH and two “wings” of Ni2(CO3)(OH)2 showed excellent activity in electrocatalytic oxygen evolution reaction attributable to the increase of higher-valance Ni3+ in the heterostructure. 相似文献
808.
Hugh D. Selby Bryan K. Roland Jenine R. Cole Zhiping Zheng 《Macromolecular Symposia》2004,209(1):23-40
The [Re6(μ3-Se)8]2+ core-containing cluster complexes of the general formula [Re6(μ3-Se)8(PEt3)4L2]2+ (both trans- and cis-isomers) site-differentiated with inert PEt3 and functional L ligands that are capable of hydrogen bonding or secondary (with respect to primary coordination with the cluster core) metal-ligand coordination interactions have been prepared. The applications of such stereospecific cluster isomers as building blocks for supramolecular construction have been studied. A great variety of multicluster arrays mediated by intercluster hydrogen bonding or cluster ligand coordination with secondary metal ions have been obtained and structurally characterized. The findings from this research clearly establish the superior utility of these novel building blocks for the creation of structurally sophisticated architectures and possibly functional materials. 相似文献
809.
Dr. Leiming Guo Dr. Konstantinos Ntetsikas Dr. Georgios Zapsas Dr. Roshni Thankamony Prof. Zhiping Lai Prof. Nikos Hadjichristidis 《Angewandte Chemie (International ed. in English)》2023,62(4):e202212400
The great significance of boosting the design of percolating nanopore structures in block copolymers (BCPs) for various cases has been widely demonstrated in the past several decades. However, it still remains challenging to prepare the desired porous structures in a rapid, facile, and universal manner. Here we have developed an unconventional and benchtop strategy to rapidly generate the nanoporous polystyrene-based BCPs with arbitrary structural characteristics regardless of the BCP bulk morphology. This universal pore-forming strategy enables the sustainable CO2-based BCPs to form advanced membranes after 1 s soaking for efficiently rejecting 94.2 % brilliant blue R (826 g mol−1). Meanwhile, the water permeance retains around 1020 L (m2 h bar)−1, which is 1–3 orders of magnitude higher than that of other membranes. This strategy may offer an excellent opportunity to introduce percolating pore structures in those newly developed BCPs with which the previously reported pore-forming methods may not deal. 相似文献
810.
Gan Tian Wang Jin Liao Yunlong Lin Zhiping Wu Fugen 《Journal of Solid State Electrochemistry》2023,27(4):1045-1053
Journal of Solid State Electrochemistry - The FeCoS2/rGO was synthesized by a one-step hydrothermal method, which has the advantages of environmental friendliness and low cost. Dense and... 相似文献