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31.
32.
本文首次研究了以β二酮及酯作为配体的六种过渡金属配合物的热稳定性,并用DTA-TG和TG-DTG技术研究了配合物的热分解机理,根据分解热估算出配合物的断裂键能。 相似文献
33.
It is difficult to directly dope europium complexes in gel because the excessive water or high acidic condition may lead to their decomposition. We prepared a novel homogeneous TiO2 gel containing Eu-phen complexes by using an in-situ synthesis method. The formation of Eu-phen complexes in sol-gel derived TiO2 was confirmed by luminescence excitation spectra. The effects of temperature and aging time on in-situ synthesis are discussed. The luminescence spectra of gel containing europium complexes were also compared with the pure Eu-phen complexes. 相似文献
34.
In this paper the solidification behavior of Sn-Sb peritectic alloy and the mechanism of grain refinement in solidification process under high-intensity ultrasonic field are investigated. Three different powers of high-intensity ultrasound are introduced into molten Sn-Sb peritectic alloy to study the refining effectiveness. The results show that the application of high-intensity ultrasound during solidification process of Sn-Sb peritectic alloy can refine α phase and β phase and eliminate gravity segregation of the alloy. As acoustic intensity is increased from 400 W to 800 W, not only the homogenous fine structure can be obtained, but also the cubic β phase crystals tend to be spherical. Microstructure of the sample treated by 600 W high-intensity ultrasound demonstrates the best refining effect. 相似文献
35.
分析了Al原子和Mn原子在二十面体准晶中的排列,计算并推导出了在急冷制备过程中,温度变化范围大约在1290.9℃,而熔炉的温度必须达到1810.9℃才能保证二十面体结构的生成,而且要控制温度变化速率,以减少Al晶体生成.而这种二十面体结构是亚稳定的,它在任何温度下存放一定时间都会发生相变. 相似文献
36.
The electrodeposition of zinc-nickle alloy was obtained on a copper cathode of 1×1cm2. The deposited alloys are quantitatively analyzed by atomic absorption spectrometry. The morphology of the deposits was observed
by means of scanning electron microscopy (SEM). We observed that the electrodeposition of zinc-nickle alloy is an anomalous
codeposition. The catalytic effects of SCN” on the electrochemical behavior of Ni deposition and hydrogen discharge are obvious.
SEM analysis shows that the surface morphology of the coating appears to be more compact and homogeneous with the increase
of SCN” concentration.
Supported by the State Key Lab. for Phys. Chem. of Solid Surface, Xiamen University 相似文献
37.
利用姜黄素在强酸非水介质中与硼酸生成有色络合物测定微量硼 ,并进行比色测定 ,方法检出限为 7 7× 10 - 8g mL ,相对标准偏差为 0 5 9% (3 3× 10 - 7g mL ,姜黄素 ,n =10 ) ,线性范围 :2 0× 10 - 7~ 1 2× 10 - 6g mL . 相似文献
38.
The active control of rotor vibration was studied while shape memory alloy (SMA) spring component was chosen as bearing of rotor system. The vibration of rotor system was controlled by the phase transformation of SMA with electric heating method. The SMA spring component has nonlinear coupling problem of thermal stress and thermal elasticity, because thermal constants α,β and elasticity constants γ, G vary with temperature when temperature changes sharply. Because δ,ε were both small parameters, their square items could be ignored and approximate results were obtained by perturbation. The characters of α,β, γ, G changing with temperature were analyzed. Results show that the character of thermal diffusivity ot changes with temperature, which cannot influence U,Ψ,So the nonlinearity of ot can be ignored; the character of,β changes with temperature,which cannot influence U, but influences Ψ at high temperature; the character of γ, G change with temperature, which cannot influence Ψ, but influences U with U^(01) ε. The more γ ,G, the more their influence on U;the nonlinearity of βT/pcvεkk influences U and Ψ, which must be calculated. 相似文献
39.
通过对不同热处理和时效处理工艺的Mn-Cu合金的X射线分析、微观组织分析和阻尼性能测试,分析了热处理冷却方式、时效处理时间对合金组织和阻尼性能的影响。研究表明,时效处理不会产生新相,随着时效处理时间的增加,晶粒尺寸增大,阻尼性能提高,但超过一定时间,阻尼性能反而降低,其中时效处理8 h能够获得最佳的阻尼性能。 相似文献
40.
The Kinetics of Hydrogen Diffusion in Ti_3Al-Based Alloy 总被引:1,自引:0,他引:1
lIntroductionAIloysbasedOI1inter111etanicsTi3AlI1avebee11stndied..inconsiderabledetaiIinrecentvearsI"'1.Theyarelegiti111ateca11didaten1ateriajsforaerospaccsysten1s,suCI1asenginesa11dairti-al11esofahydrogen-burl1ingpropulsion'syste111.Tl1erefore,theinterac… 相似文献