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1.
Wang Weishu Yuan Man Li Yun-Ze Li Chuang Ning Xian-Wen Li Tong 《Journal of Thermal Analysis and Calorimetry》2021,143(1):559-571
Journal of Thermal Analysis and Calorimetry - Sublimator offers effective heat rejection for the spacecraft, which work in warm environments or with peak heat loads, by evaporating or sublimating... 相似文献
2.
酸碱质子理论是普通化学中的重要模块。学习酸碱质子理论一般从弱酸水溶液入手,若将应用范围扩展为所有含质子的化合物,该理论将被赋予更多的内涵。在含质子的已知化合物中,Ka的范围十分宽广,跨越了100个数量级以上。哪种酸碱“最强”一直是学生间喜闻乐见的话题,以此话题出发,介绍了常见的超强酸、超强碱与相关概念及应用。这些概念的介绍不仅拓展了学生的视野,更能够加深学生对酸碱质子理论的理解,对未来分析化学、无机化学、有机化学的教育产生积极意义。 相似文献
3.
Cuprous chloride was coordinated by diazabutadiene (DAB‐R) ligands to form Cu(I)‐(DAB‐R) complexes, most of which have a 1:1 ratio of Cu to DAB‐R as reported. In the case of a special DAB‐iPP, N,N′‐bis(2,6‐diisopropylphenyl)‐1,4‐diaza‐1,3‐butadiene, an unexpected composition of complex was found with the formula Cu(I)Cl(DAB)2. When employed as catalyst for triarylamine synthesis from the coupling of aryl halides with primary and secondary arylamines, the new Cu(I)‐(DAB‐iPP) complex displayed high efficiency. 相似文献
4.
An on-line solid phase extraction-high performance liquid chromatography-tandemmass spectrometry method for the analysis of perfluoroalkyl substances (PFASs) in water samples was developed. The optimal analytical conditions were obtained through the optimization of the extraction efficiency of online solid phase extraction column, sample loading rate and loading volume, and the concentration of ammonium acetate in mobile phase. Under the optimal condition, the analytical method displayed good linearity (r2 > 0.99) for 12 PFASs (C5-C14 perfluoroalkyl carboxylic acids and C6/C8 perfluoroalkyl sulfonic acids) over a concentration range of 0.5-100 ng/L. The limits of quantitation for samples were between 0.025 ng/L and 0.5 ng/L and the relative standard deviations (RSD) of five consecutive analyses were less than 10% for 1 ng/L standard solution. Satisfactory results were obtained using this analytical method for the analysis of perfluoroalkyl substances in Antarctic ice core samples. The recoveries of all perfluoroalkyl substances were in a range of 73%-117% when the sampleswere spiked with standards at the concentrations of 2.5 ng/L and 25 ng/L. 相似文献
5.
6.
Molecular dynamics (MD) simulations using Morse interaction potential are performed in studies of [110] symmetrical tilt grain
boundary (GB) structures with mis-orientation angles 50.5°(Σ11), 129.5°(Σ11), 70.5°(Σ3) and 109.5°(Σ3) at various tempratures.
The GB structures are found to start local disordering at about 0.5T
m
(T
m
is the melting point of aluminium) for 50.5°(Σ11), 0.32T
m
for 129.5° (Σ11) and 0.38T
m
for 70.5°(Σ3), respectively. These results agree with conclusions deduced from the anelastic measurements. But, for twin-boundary
structure 109.5°(Σ3), this disordering has not been found even when temperature increases up to 0.9T
m
.
The project supported by the National Natural Science Foundation of China and Laboratory for Non-linear Mechanics of Continuous
Media, Institute of Mechanics, Academia Sinica. 相似文献
7.
A numerical analysis of flow and concentration fields of macromolecules in a, slightly curved blood vessel was carried out.
Based on these results, the effect of the bifurcation of a flow on the mass transport in a curved blood vessel was discussed.
The macromolecules turned out to be easier to deposit in the inner part of the curved blood vessel near the critical Dean
number. Once the Dean number is higher than the critical number, the bifurcation of the flow appears. This bifurcation can
prevent macromolecules from concentrating in the inner part of the curved blood vessel. This result is helpful for understanding
the possible correlations between the blood dynamics and atherosclerosis.
The project supported by National Natural Science Foundation of China (10002003), JSPS Postdoctoral Fellowship for Foreign
Researcher and Foundation for University Teachers, the Ministry of Education 相似文献
8.
In a vertically oscillating circular cylindrical container, singular perturbation theory of two-time scale expansions is developed in weakly viscous fluids to investigate the motion of single free surface standing wave by linearizing the Navier-Stokes equation. The fluid field is divided into an outer potential flow region and an inner boundary layer region. The solutions of both two regions are obtained and a linear amplitude equation incorporating damping term and external excitation is derived. The condition to appear stable surface wave is obtained and the critical curve is determined. In addition, an analytical expression of damping coefficient is determined. Finally, the dispersion relation, which has been derived from the inviscid fluid approximation, is modified by adding linear damping. It is found that the modified results are reasonably closer to experimental results than former theory. Result shows that when forcing frequency is low, the viscosity of the fluid is prominent for the mode selection. However, when forcing frequency is high, the surface tension of the fluid is prominent. 相似文献
9.
This paper proposes a method for simualting symmetric and simulating symmetric and asymmetric typhoonby using Rankine vortex model. Considering similarity between tropical cyclone andthe Rankine vortex,the paper has qualitatively discussed the feasibility of the methods In order to decide quantitatively Rankine vortex’s parameters to simulate typhoon’s structure, the paper has dealt with TCM data.for Yancy Typhoon (9012) as initial fields.. These results are considered as a foundation for further studying typhoon motion by CD approach. 相似文献
10.
ZhangYin ZhaoYa-pu 《Acta Mechanica Solida Sinica》2004,17(2):104-112
I. INTRODUCTION For capacitor-like microelectromechanical systems (MEMS) structure[1??6], the voltage betweenthe structure and substrate causes attractive force. The sources of the voltage can be an arti?ciallymounted device[2 , 7??9] or the temporar… 相似文献