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1.
半浮区液桥热毛细对流速度场特征   总被引:1,自引:1,他引:1  
液桥流场的速度分布是液桥表面张力梯度驱动对流的一个重要研究内容。通过地面模拟微重力环境的液桥实验以及数值计算,研究了外加温差、液桥腰径等对流场速度分布的影响,实验结果与数值计算结果相当符合。结果还表明,当液桥腰径减小时,流场的结构发生了变化,涡心由一个转化成两个。  相似文献   
2.
International Journal of Theoretical Physics - Quantum-dot is the result of elastic relaxation which has a straight relationship with the optical and electronic aspects of the quantum-dot-based...  相似文献   
3.
Pan  Shiwei  Li  Puhui  Xu  Guihua  Guo  Jingchang  Ke  Libin  Xie  Canquan  Zhang  Zhoucai  Hui  Yonghai 《Research on Chemical Intermediates》2020,46(2):1353-1371
Research on Chemical Intermediates - Heterogeneous ordered mesoporous silica materials catalyst, MCM-41@Schiff base-Co(AcO)2, reveals high catalytic performance within the synthesis of pyran...  相似文献   
4.
以TiO2包覆的多壁碳纳米管(CNT@TiO2)为载体,Pt和Au为活性物质,采用沉积紫外光催化还原法制备出高活性的甲醇阳极电催化剂Pt-Au/CNT@TiO2,并采用X射线衍射、透射电镜和X射线光电子能谱对催化剂样品的物化特征进行表征.催化剂的抗毒性能用循环伏安和交流阻抗测试来表征.结果表明,粒径为2~3nm的Pt-...  相似文献   
5.
The enlargement of the emitting aperture is usually one of the important methods of increasing vertical- cavity surface-emitting laser (VCSEL) optical output power. However, in a VCSEL with a larger aperture, the inhomogeneity in the injected current often causes inhomogeneous or even no emission. To solve this problem and to increase VCSEL output power, as well as to improve its thermal characteristics, we develop a new type of injected VCSEL with a larger aperture and a reticular electrode, where the conventional circular injection electrode of the P side is turned into a reticular one, and the heat sink is on the N side. The tests of the new VCSEL show an improvement in homogeneity in not only the injected current but also the emission intensity. The optical output power is also considerably increased, and the device optoelectronic performance is improved.  相似文献   
6.
The rigorous analytical solutions and the ABCD matrix of the lossy Cosine-Squared tapered nonuniform transmission lines (CSTNTL) are presented in this paper. According to different boundary conditions, the unique solution is obtained mathematically. Through the numerical calculations based on analytical solutions, the distributed voltages and currents in different terminated cases are shown to explain the transmission characteristics of CSTNTL. Especially in the lossy case the distributed power values are simulated to show the attenuation phenomenon.  相似文献   
7.
Four ternary complexes of Tb(III) were synthesized by introducing the first ligand (L1) (N-phenylanthranilic acid (N-HPA), α-furoic acid (FURA)) and the second ligand (L2) (1,10-phenanthroline (Phen), 2,2′-dipyridyl (Bipy)), respectively. These complexes were characterized by elemental analysis, infrared spectra, XRD, UV spectra and fluorescence spectra. The effect of L1 and L2 on the fluorescence properties of terbium complexes was discussed. It showed that all the complexes exhibited ligand-sensitized green emission. The fluorescent intensity increased in the sequence of Tb(FURA)3Bipy < Tb(N-PA)3Phen < Tb(FURA)3Phen < Tb(N-PA)3Bipy. It indicated that L1 affected fluorescence properties of the complexes differently when the corresponding L2 altered. Meanwhile, the influence of L2 on the luminescence properties of the complexes also depends on L1. The results showed that L1 and L2 affected each other and worked together as a whole. The matching of L1, L2 and Tb3+ ion is very important to the luminescence properties of Tb(III) ternary complexes.  相似文献   
8.
1,5‐diaminotetrazolium chloride (DATC) and 1,5‐diaminotetrazolium sulfate (DATS) were synthesized in this work. The structures of DATS and DATC were characterized. The single crystal of DATS was first cultured, and its structure was analyzed. The thermal behavior of DATS was investigated. The activation energy and pro‐exponential factor were calculated, Ek = 120.86 KJ/mol, Ak = 1012.96 s?1. The density, heat of formation, detonation pressure, and detonation velocity of DATS were first calculated. The detonation pressure and detonation velocity of DATS are P = 11.877 GPa, D = 5.617 km s?1, which are smaller than those of 1,5‐diaminotetrazolium nitrate (DATN) (P = 33.3GPa, D = 8.77 km s?1).  相似文献   
9.
ZnO films were deposited on c-plane Al2O3 substrates by pulsed laser deposition. The etching treatments for as-grown ZnO films were performed in NH4Cl aqueous solution as a function of NH4Cl concentration and etching time. It was found that NH4Cl solution is an appropriate candidate for ZnO wet etching because of its controllable and moderate etching rate. The influence of etching treatment on the morphology, optical and electrical properties of the ZnO films has been investigated systematically by means of X-ray diffraction, atomic force microscope, photoluminescence and Hall effect. The results indicated that the surface morphology and optical properties of the films were highly influenced by etching treatment.  相似文献   
10.
Equilibrium geometries, interaction energies, and charge transfer for the intermolecular interactions between BrF and HnX (HF, H2O, and NH3) were studied at the MP2/6-311++G(3d,3p) level. The halogen-bonded geometry and hydrogen-bonded geometry are observed in these interactions. The calculated interaction energies show that the halogen-bonded structures are more stable than the corresponding hydrogen-bonded structures. To study the nature of the intermolecular interactions, symmetry-adapted perturbation theory (SAPT) calculations were carried out and the results indicate that the halogen bonding interactions are dominantly inductive energy in nature, while electrostatic energy governs the hydrogen bonding interactions.  相似文献   
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