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41.
We show that the Cauchy problem for a class of dispersive perturbations of Burgers' equations containing the low dispersion Benjamin–Ono equation
?tu?Dxα?xu=?x(u2),0<α1,
is locally well-posed in Hs(R) when s>sα:=32?5α4. As a consequence, we obtain global well-posedness in the energy space Hα2(R) as soon as α2>sα, i.e. α>67.  相似文献   
42.
Starting from a field theory action that describes a Dirac fermion, we propose and analyze a model based on a low‐relativistic Pauli equation coupled to a torsion‐like term to study Spin Hall Effect (SHE). We point out a very particular connection between the modified Pauli equation and the (SHE), where what we refer to torsion as field playing an important role in the spin‐orbit (SO) coupling process. In this scenario, we present a proposal of a spin‐type current, considering the tiny contributions of torsion in connection with intrinsic anisotropy of the crystal electric field.  相似文献   
43.
范德瓦耳斯气液状态方程纵横谈   总被引:4,自引:1,他引:4  
胡颉  佘守宪 《大学物理》2005,24(10):15-20
首先强调了范氏方程是气液系统的状态方程,范氏方程可以很好地说明物质气态和液态的相互转变.分析了焦-汤效应,简述了气体的液化与低温的获得.  相似文献   
44.
In the context, some lanthanide (Eu3+, Tb3+ and Sm3+) complexes with conjugated carboxylic acids (pyridine-carboxylic acids derivatives) have been synthesized and characterized. The low temperature fluorescent spectra for these complexes have been measured at nitrogen atmosphere (77 K), indicating that the central Ln3+ ions locate in an equivalent coordination environment with low symmetry for most of these lanthanide complexes belonging to dimeric or polymeric structure. Therefore, the electronic dipole transition (supersensitive transition) (5D07F2 for Eu3+, 5D47F6 for Tb3+, 4G5/26H9/2 for Sm3+) and magnetic dipole transition (5D07F1 for Eu3+, 5D47F5 for Tb3+, 4G5/26H5/2 for Sm3+) show the regular change in the corresponding split number of fluorescent spectra, which can be realized to predict the fine structure of lanthanide complexes.  相似文献   
45.
基于超二代像增强器的微光夜视仪设计   总被引:1,自引:1,他引:1  
提出了一种设计手持式微光夜视仪的思路,选择了高质量的超二代像增强器,设计了性能优良的光学系统,进行了精细的像差校正,实现了Gen II+像增强器、光学系统和人眼的光谱匹配.在10-3 lx照度下,对人视距提高到350~400 m,对车辆视距达到700~900 m.  相似文献   
46.
Crystallization Behavior of Sol-Gel Derived Films by Self-Seeding Process   总被引:2,自引:0,他引:2  
We propose the novel preparation method, Self-seeding Process, based on the following concept for low temperature crystallization of oxide films. Introduction of desirable inhomogeneity should give lowering of a crystallization temperature through heterogeneous nucleation accompanied with reduced activation energy. We carried out inspection of the above concept through use of PZT films. PZT gel films with the desirable inhomogeneity of microstructure were prepared, and their crystallization behaviors was examined. The PZT film was successfully crystallized at 500°C by the self-seeding process. The single phase (001) oriented PZT film with 0.55 m in thickness was obtained at 550°C for 5 min. The self-seeding process by microstructure control is efficient for the low temperature process of the oxide thin film.  相似文献   
47.
Not copy and paste: Although β-diketiminato ligands have been employed for the stabilization of Ge(II) and Sn(II) hydrides, the corresponding Si(II) hydride is not accessible. However, coordination of silicon(II) to a {Ni(CO)(3)} fragment allowed the isolation of the first Si(II) hydride metal complex 1. This complex was used for the first silicon(II)-based and Ni(0)-mediated, stereoselective hydrosilylation of alkynes. R = phenyl, tolyl.  相似文献   
48.
新型的承载双金属氰化物络合催化剂   总被引:1,自引:0,他引:1  
于剑昆 《广州化学》2004,29(3):47-54
用双金属氰化物(DMC)络合催化剂可制得相对分子质量高、相对分子质量分布窄和不饱和度低的聚醚多元醇。为提高DMC催化剂的利用率,降低催化剂和聚醚的生产成本,国外开发了承载的DMC催化剂。它不仅可简化聚醚的后处理工艺,而且使聚醚的连续化大规模生产得以实现,因此代表了DMC催化剂的一个重要发展方向。  相似文献   
49.
In this study, detection of staphylococcal enterotoxin A (SEA) in multi-matrices using a highly sensitive and specific microplate chemiluminescence enzyme immunoassay (CLEIA) has been established. A pair of monoclonal antibodies (mAbs) was selected from 37 anti-SEA mAbs by pairwise analysis, and the experimental conditions of the CLEIA were optimized. This CLEIA exhibited high performance with a wide dynamic range from 6.4 pg mL−1 to 1600 pg mL−1, and the measured low limit of detection (LOD) was 3.2 pg mL−1. No cross-reactivity was observed when this method was applied to test SEB, SEC1, and SED. It has also been successfully applied for analyzing SEA in a variety of environmental, biological, and clinical matrices, such as sewage, tap water, river water, roast beef, peanut butter, cured ham, 10% nonfat dry milk, milk, orange juice, human urine, and serum. Thus, the highly sensitive and SEA-specific CLEIA should make it attractive for quantifying SEA in public health and diagnosis in near future.  相似文献   
50.
吴里程  王谦  赵炜 《分子催化》2018,32(1):63-69
制备了一种新的氟掺杂氧化钒/氧化钛催化剂,探讨了掺杂模式、制备方法对低温SCR活性的影响.结果显示,在120~240℃反应温度下,由溶胶法制得的氟掺杂于钒(F-V)模式下的催化活性最佳,通过与未掺杂催化剂(COM)对比可知,在210℃时,氟掺杂催化剂的活性提高了35%,并于240℃时NO的脱除率达到了98.6%.通过X射线衍射试验(XRD)、透射电子显微镜(TEM)、比表面积测试(BET)、光电子能谱分析(XPS)以及H_2程序升温还原(H_2-TPR)等表征技术显示氟掺杂引起催化剂SCR活性提升主要与催化剂活性成分的良好分散性、粒子尺寸减小、比表面积及孔容增大、更强的氧化还原能力有关.另外,通过试验研究表明,氟掺杂催化剂不仅提升了SCR活性,拓宽了活性温度范围,而且还增强了抗硫与抗水性能.  相似文献   
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