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901.
902.
We prove a Freidlin-Wentzell large deviation principle for multi-dimensional stochastic differential equations with non-Lipschitz coefficients and apply it to the Brownian motion on the diffeomorphism group of the disc constructed recently by Airault, Malliavin and Thalmaier. 相似文献
903.
904.
905.
Jen-Huang Jeng Hsieh T.E. 《Components and Packaging Technologies, IEEE Transactions on》2001,24(2):271-278
This work demonstrates the probing, testability and applicability of Al/PI (aluminum/polyimide) composite bumps to the chip on-glass (COG) bonding process for liquid crystal display (LCD) driver chip packaging. The experimental results showed that the thickness of Al overlayer on PI core of the bump, the location of pin contact, and the bump configuration affect bump probing testability. The bump with type IV configuration prepared in this work exhibited excellent probing testability when its Al overlayer thickness exceeded 0.8 μm. We further employed Taguchi method to identify the optimum COG bonding parameters for the Al/PI composite bump. The four bonding parameters, bonding temperature, bonding time, bonding pressure and thickness of Al overlayer are identified as 180° C, 10 s, 800 kgf/cm2 and 1.4 μm, respectively. The optimum bonding condition was applied to subsequent COG bonding experiments on glass substrates containing Al pads or indium tin oxide (ITO) pads. From the results of resistance measurement along with a series of reliability tests, Al pad is found to be a good substrate bonding pad for Al/PI bump to COG process. Excellent contact quality was observed when the bumps had Al overlayer thickness over 1.1 μm. As to the COG specimens with substrate containing ITO pads, high joint resistance suggested that further contact quality refinement is necessary to realize their application to COG process 相似文献
906.
The electronic structure, charge distribution, and chemical bonding of the dimer of bis-(η5-cyclopentadienyl)ytterbium methyl have been studied by an unrestricted INDO program made applicable for the lanthanoid compounds [1]. The bond order, composition, and the nature of the bridge bonds have been discussed. The existence of weak interaction between two ytterbium atoms was shown. 相似文献
907.
John D. Dow Shang Yuan Ren Jun Shen Run-Di Hong Ruo-Ping Wang 《Journal of Electronic Materials》1990,19(8):829-835
The physics governing deep levels in superlattices and quantum wells is elucidated, with emphasis on the importance of shallow-deep
transitions caused by a band edge passing through a deep level, and the accompanying change in doping character of the impurity. 相似文献
908.
909.
Thecoordinationchemistryofbinuclearmetalcomplexeshasbeenasubjectofextensiveinvestigationrelatingtothesynthesisofmodelcompoundsforthemetal-bindingsitesofmetal1oproteinsthatrequirethepresenceoftWometalcentersl.Duringthe1astdecade,anumberofsyntheticstructuraImodeIsfortheseproteinswiththeuseofseveraltypesofligandshavebeenreportedinIiterature2-4.ForIigandswithanappropriatedispositionofdonoratoms,ithasbeenpossibletoshowthepresenceofhydroxo,imidazolato,azido,andthiocyanatobridgesbetweenmetalions5.T… 相似文献
910.
Yuanlin Ren Bowen Cheng Jinshu Zhang Weimin Kang Zhenhuan Li Xupin Zhuang 《Frontiers of Chemistry in China》2009,4(2):136-141
The thermal decomposition kinetics of the N,N′-bis(5,5-dimethyl-2-phospha-2-thio-1,3-dioxan-2-yl) ethylenediamine (DPTDEDA) in air were studied by TGDTG techniques. The
kinetic parameters of the decomposition process for the title compound in the two main thermal decomposition steps were calculated
through the Friedman and Flynn-Wall-Ozawsa (FWO) methods and the thermal decomposition mechanism of DPTDEDA was also studied
with the Coats-Redfern and Achar methods. The results show that the activation energies for the two main thermal decomposition
steps are 128.03 and 92.59 kJ·mol−1 with the Friedman method, and 138.75 and 106.78 kJ·mol−1 with the FWO method, respectively. Although there are two main thermal decomposition steps for DPTDEDA in air, the thermal
decomposition mechanism of DPTDEDA in the two steps are the same, i.e. f(α) = 3/2(1 − α)4/3[(1 − α)−1/3 − 1]−1.
__________
Translated from Acta Chimica Sinica, 2008, 66(9) (in Chinese) 相似文献