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排序方式: 共有239条查询结果,搜索用时 9 毫秒
71.
TAN Xu-Liang ZHANG Fu-Xing HE Li-Fang GUI Shi-Yin ZHANG Yi-Ling ZHU Xiao-Ming SHENG Liang-Bing FENG Yong-Lan YU Jiang-Xi JIANG Wu-Jiu 《结构化学》2021,40(5):675-681
Tri(o-chlorobenzyl)tin 2,4,6-trimethylbenzoate(1)and tri(o-bromobenzyl)tin salicylate(2)were synthesized and characterized by elemental analysis,1R spectroscopy... 相似文献
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73.
İsmaıl Nacı Cangül Musa Demırcı İlker İnam Florian Luca Gökhan Soydan 《Mathematica Slovaca》2013,63(3):647-659
In this note, we find all the solutions of the Diophantine equation x 2 + 2 a · 3 b · 11 c = y n , in nonnegative integers a, b, c, x, y, n ≥ 3 with x and y coprime. 相似文献
74.
Qiang Zhang Cang Huang Dong Jiang Xiaobo Wei Zhen Qian Fei Wei Beijing Key Laboratory of Green Chemical Reaction Engineering Technology 《中国颗粒学报》2009,7(3)
Based on three-dimensional (3D) acceleration sensing, an intelligent particle spy capable of detecting, transferring, and storing data, is proposed under the name of Particle Measurement Sensor (PMS). A prototype 60-mm-dia PMS was tested to track its freefall in terms of velocity and displacement, and served as a particle spy in a fluidized bed delivering the in situ acceleration information it detects. With increasing superficial gas velocity in the fluidized bed, the acceleration felt by PMS was observed to increase. The variance of the signals, which reflect the fluctuation, increased at first, reaching a maximum at the gas velocity (Uc) which marks the transition from bubbling to turbulent fluidization. Through probability density distribution (PDD) analysis, the PDD peak can be divided into the emulsion phase peak and the bubble phase peak. The average acceleration of emulsion and bubble phase increased, while the variance of both phases reached a maximum at Oc, at the same time. However, the difference between the variances of two phases reached the maximum at Oc. Findings of this study indicate that PMS can record independent in situ information. Further, it can provide other in situ measurements when equipped with additional multi-functional sensors. 相似文献
75.
The Cang Nguyen 《Annales Henri Poincare》2016,17(8):2237-2263
In this paper, we introduce new methods for solving the vacuum Einstein constraints equations: the first one is based on Schaefer’s fixed point theorem (known methods use Schauder’s fixed point theorem), while the second one uses the concept of half-continuity coupled with the introduction of local supersolutions. These methods allow to: unify some recent existence results, simplify many proofs (for instance, the one of the main theorems in Dahl et al., Duke Math J 161(14):2669–2697, 2012) and weaken the assumptions of many recent results. 相似文献
76.
A novel nanoparticle-nanorod composite TiO(2) photoelectrode is fabricated. A 3.20% efficiency is achieved by using a 2.1 μm-thick as-prepared photoelectrode, which is about 3 times of that obtained by a nanorod array electrode (1.05%). The results demonstrate that the composite nanostructure can take advantage of both fast electron transport (nanorod) and high surface area (nanoparticle). 相似文献
77.
A Kiselyuk SH Lee S Farber-Katz M Zhang S Athavankar T Cohen AB Pinkerton M Ye P Bushway AD Richardson HA Hostetler M Rodriguez-Lee L Huang B Spangler L Smith J Higginbotham J Cashman H Freeze P Itkin-Ansari MI Dawson F Schroeder Y Cang M Mercola F Levine 《Chemistry & biology》2012,19(7):806-818
Hepatocyte nuclear factor (HNF)4α is a central regulator of gene expression in cell types that play a critical role in metabolic homeostasis, including hepatocytes, enterocytes, and pancreatic β cells. Although fatty acids were found to occupy the HNF4α ligand-binding pocket and were proposed to act as ligands, there is controversy about both the nature of HNF4α ligands as well as the physiological role of the binding.?Here, we report the discovery of potent synthetic HNF4α antagonists through a high-throughput screen for effectors of the human insulin promoter. These molecules bound to HNF4α with high affinity and modulated the expression of known HNF4α target genes. Notably, they were found to be selectively cytotoxic to cancer cell lines in?vitro and in?vivo, although in?vivo potency was limited by suboptimal pharmacokinetic properties. The discovery of bioactive modulators for HNF4α raises the possibility that diseases involving HNF4α, such as diabetes and cancer, might be amenable to pharmacologic intervention by modulation of HNF4α activity. 相似文献
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79.
The Schrödinger equation with the modified Pöschl‐Teller (MPT) potential is studied by working in a complete square integrable basis that supports a tridiagonal matrix representation of the wave operator. The resulting three‐term recursion relation for the expansion coefficients of the wavefunction is presented, and the wavefunctions are expressed in terms of the Jocobi polynomial. The discrete spectrum of the bound states is obtained by diagonalization of the recursion relation. © 2011 Wiley Periodicals, Inc. Int J Quantum Chem, 2011 相似文献
80.
Ju‐Ying Hou Qi‐Yu Yang Han‐Hui Zhang Yi‐Ping Chen Jian‐Fu Xu Chang‐Cang Huang 《Acta Crystallographica. Section C, Structural Chemistry》2005,61(6):i59-i60
A new three‐dimensional bimetallic tellurite, BaV2TeO8, was synthesized by the hydrothermal reaction of Ba(OH)2, TeO2 and V2O5, and characterized by single‐crystal X‐ray diffraction. The three‐dimensional framework is built up from anionic [V2TeO8]n2n− layers parallel to (101) and connected via Ba—O bonds. The anionic layers are formed by three types of polyhedra, namely VO5 tetragonal pyramids, VO4 tetrahedra and TeO4+2 `folded square' polyhedra. 相似文献