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971.
Journal of Statistical Physics - We consider the spherical spin glass model defined by a combination of the pure 2-spin spherical Sherrington–Kirkpatrick Hamiltonian and the ferromagnetic... 相似文献
972.
973.
Chengchun Hao 《Zeitschrift für Angewandte Mathematik und Physik (ZAMP)》2012,63(5):825-834
We investigate the Cauchy problem of a multidimensional chemotaxis model with initial data in critical Besov spaces. The global existence and uniqueness of the strong solution is shown for initial data close to a constant equilibrium state. 相似文献
974.
975.
Abstract . The solvothermal reaction between cuprous iodide and the rigid triangular imidazole ligand in mixed N,N′‐dimethylacetamide (DMA)‐acetonitrile solvent leads to the isolation of the 3D metal‐organic framework [(Cu4I4)3(TIPA)4] · 7DMA ( 1 ) [TIPA = tri(4‐imidazolylphenyl) amine], which was characterized by elemental analysis, IR spectroscopy, powder X‐ray diffraction, and single‐crystal X‐ray diffraction. Topologically, the structure of 1 is an unprecedented 3,3,4,4‐connected net with a point symbol of {4.8.10}2{4.82}2{42.82.102}2{84.122}. Compound 1 exhibits orange‐red photoluminescence with an emission maximum at 622 nm at room temperature. 相似文献
976.
977.
A moving particle semi‐implicit method for free surface flow: Improvement in inter‐particle force stabilization and consistency restoring 下载免费PDF全文
The moving particle semi‐implicit (MPS) method has been widely applied in free surface flows. However, the implementation of MPS remains limited because of compressive instability occurred when the particles are under compressive stress states. This study proposed an inter‐particle force stabilization and consistency restoring MPS (IFS‐CR‐MPS) method to overcome this numerical instability. For inter‐particle force stabilization, a hyperbolic‐shaped quintic kernel function is developed with a non‐negative and smooth second order derivative to satisfy the stability criterion under compressive stress state. Then, a contrastive study is conducted on the contradiction between the common understanding of the conventional MPS hyperbolic‐shaped kernel function and its performance. The result shows that the conventional MPS hyperbolic‐shaped kernel function can easily cause violent repulsive inter‐particle force and then lead to the compressive instability. Therefore, the first order derivative of the modified hyperbolic‐shaped quintic kernel function is recommended as the form of the contribution of the neighbor particles to achieve a more stable inter‐particle repulsive force. For consistency restoring, the Taylor series expansion and the hyperbolic‐shaped quintic kernel are combined to improve the accuracy of the viscosity and pressure calculation. The IFS‐CR‐MPS algorithm is subsequently verified by the inviscid hydrostatic pressure, jet impacting, and viscous droplet impacting problems. These results can be used for choosing kernel function and the contribution of neighbor particles in particle methods. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献
978.
The metal-catalyzed Baeyer-Villiger oxidation of cyclohexanone with molecular oxygen (latm) in the presence of benzaldehyde gives δ -caprolactone in high yield. The same oxidation in the absence of metal catalysts is also studied. Additives to the system can improve the reaction highly efficiently. 相似文献
979.
980.
Dr. Qianjia Yuan Prof. Matthew S. Sigman 《Chemistry (Weinheim an der Bergstrasse, Germany)》2019,25(46):10823-10827
In this report, a palladium-catalyzed redox-relay Heck process to access optically active alkenylated α,β-unsaturated lactams is described. Under mild reaction conditions, electron-deficient alkenyl triflates and electron-rich alkenyl iodonium salts undergo enantioselective and site-selective coupling with enelactams to deliver the products in high yields and excellent enantioselectivities. Furthermore, the products allow facile access to natural products such as (+)-calvine and (+)-2-epicalvine in addition to the bioactive molecule aza-goniothalamin. 相似文献