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91.
Nicholas Kob Russell S. Drago Vaneica Young John Osegovic 《Reaction Kinetics and Catalysis Letters》1999,66(2):205-210
The regeneration of solid acid catalysts used in alkylation was studied using cal-ad. It was found that an acid site strength
of −ΔH=32 kcal/mol is needed to catalyze the reaction. 相似文献
92.
The novolac-based resins used as positive-tone photoresists are frequently etched in an oxygen plasma. It is desirable to have a predictive model of the photoresist etch rate but, for process improvement, control, and analysis, the development of a rigorous mechanistic model is impractical. Instead, a simplified mechanistic model is derived, here, according to the method proposed by Hougen and Watson for the study of fluid–solid interactions. This model derivation method is employed in order to arrive at a functional form that represents chemical etching of the resist by oxygen radicals, assisted by the plasma ion flux. Values for model parameters are determined from process data by nonlinear regression. The quality of the model fit to the data is tested statistically. 相似文献
93.
G.A. Cooper J.P. Graves W.A. Cooper R. Gruber R.S. Peterson 《Journal of computational physics》2009,228(13):4911-4916
An incompressible variational ideal ballooning mode equation is discretized with the COOL finite element discretization scheme using basis functions composed of variable order Legendre polynomials. This reduces the second order ordinary differential equation to a special block pentadiagonal matrix equation that is solved using an inverse vector iteration method. A benchmark test of BECOOL (Ballooning Eigensolver using COOL finite elements) with second order Legendre polynomials recovers precisely the eigenvalues computed by the VVBAL shooting code. Timing runs reveal the need to determine an optimal lower order case. Eigenvalue convergence runs show that cubic Legendre polynomials construct the optimal ballooning mode equation for intensive computations. 相似文献
94.
95.
Russell M. Brown 《Applicable analysis》2013,92(6-7):735-749
Let Ω be a domain in R n whose boundary is C 1 if n≥3 or C 1,β if n=2. We consider a magnetic Schrödinger operator L W , q in Ω and show how to recover the boundary values of the tangential component of the vector potential W from the Dirichlet to Neumann map for L W , q . We also consider a steady state heat equation with convection term Δ+2W·? and recover the boundary values of the convection term W from the Dirichlet to Neumann map. Our method is constructive and gives a stability result at the boundary. 相似文献
96.
Xinyu Wei Weiyin Gu Le Li Xiaobo Shen Jung‐Keun Kim Thomas P. Russell 《Journal of Polymer Science.Polymer Physics》2013,51(1):78-85
We reported the synthesis and morphology of a novel alkyne‐functionalized diblock copolymer (di‐BCP) poly(methyl methacrylate‐random‐propargyl methacrylate)‐block‐poly(4‐bromostyrene). The di‐BCPs were synthesized by atom transfer radical polymerization and postpolymerization deprotection, with good control over molecular weight and polydispersity index. Microphase separation in bulk di‐BCPs was confirmed by thermal analysis, small‐angle X‐ray scattering, and transmission electron microscopy. Microphase‐separated morphologies were also observed in thin films, and the orientation of the microdomains can be conveniently controlled by annealing under different solvents. © 2012 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys, 2012 相似文献
97.
Expressions are derived for the hyperfine effect in the rotational energy levels of linear triatomic molecules in 2Π electronic states, taking into account both spin-orbit and Renner interactions. The results derived are compared with the available experimental data. 相似文献
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