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951.
全彩LED大民间葜可以用来显示电视画面。由于CRT发光特性的非线笥,在图像信号源处引入一种称为γ校正的相反预失真来补偿CRT的这种非线性。但由于全彩LED大屏幕系统的发光特性与CRT的发光特性不同,它的发光亮度与其控制量成线性关系,因此在显示电视画面时会引适合LED屏的显示。此外,还考虑到人的视觉的明亮度与物理亮度的关系。本文给出了一种对LED大屏幕信号进行校正的方法,即γ校正,实验结果表明效果极 相似文献
952.
953.
The paper proposes a FAD-SMT model of large-scale liquid chromatography by which a continuous equation of chromatographic separation is decomposed into a convection dispersion partial differential equation and a set of ordinary differential equations. The numerical method for the FAD-SMT model is established. The stability and the convergence condition of numerical solution, and the choice of time and space interval are discussed. The FAD-SMT model is used to simulate liquid adsorption chromatography and cycling adsorption chromatography. Results show that the elution curves calculated by FAD-SMT model are good agreement with the experimental elution curves of the separation of glucose and fructose, the separation of sucrose and reducing sugar and the separation of mannitol and sorbitol. The result of parameter sensitivity analysis shows that the chromatographic elution curves are more sensitive to the changes of the parameter ai in Langmuir isotherms than to the changes of other parameters in the studied system. 相似文献
954.
β-环糊精/KI3包合物的制备及性质研究 总被引:8,自引:0,他引:8
研究了室温下β-CD/KI3包合物溶液和固体的稳定性,以及固体的热分解性质,通过 1H NMR方法证实了KI3与β-CD的包结作用,并用UV/Vis方法测定了形成常数。结果表明,通过β-CD的包结作用,可增加KI3的稳定性。 相似文献
955.
The effects of the chiral substituents attached to silicon on the stereoselectivity of the reactions of C-centered chiral silicon compounds was examined. The investigation was focused on the asymmetric C-C bond formation reaction of chiral allylsilanes and α-silylallyl anions with aldehydes. The functionalities of the substituents on silicon can be manipulated to improve the stereoselectivities of the reactions remote from silicon atom. 相似文献
956.
Nora N. Nichio Mónica L. Casella Osmar A. Ferretti 《Reaction Kinetics and Catalysis Letters》1999,66(1):27-32
In this paper the activity, selectivity and mainly stability of nickel catalysts in the oxyreforming reaction are analyzed.
The catalysts were prepared employing different precursors (nickel nitrate and nickel acetylacetonate) on α-Al2O3 and α-Al2O3 modified by a layer of aluminium oxide. The catalytic sample obtained from nickel acetylacetonate on the modified support
showed the best stability. 相似文献
957.
L. Ya. Zakharova F. G. Valeeva L. A. Kudryavtseva A. I. Konovalov N. L. Zakharchenko Yu. F. Zuev V. D. Fedotov 《Russian Chemical Bulletin》1999,48(12):2240-2244
The influence of cluster formation of micelles on the rate of alkaline hydrolysis of ethylp-nitrophenyl chloromethylphosphonate in the reverse micellar sodium bis(2-ethylhexyl) sulfosuccinate (AOT)—decane—water system
was found. The applicability of the pseudo-phase model of micellar catalysis below and above the percolation threshold was
shown.
Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 12, pp. 2266–2270, December, 1999. 相似文献
958.
The values of C−H and C−I bond dissociation energies were used to calculate the enthalpies of formation (δH
f
o
of 20 cyclic and conjugated hydrocarbon radicals (R′). The values of δH
f
o
(R′) were analyzed in terms of the quantitative structure-property correlation based on the additive-group model, and the
reliability of these data was shown. Based on the correlation, several strain energies of cycles and energies of conjugation
of a lone electron with a ρ-system were calculated. The additive-group method for calculation of δH
f
o
can be extended for radicals of the naphthalyl type.
For Part 2, see Ref. 1.
Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 2, pp. 286–288, February, 1999. 相似文献
959.
Liu J.-S. Marison I. W. von Stockar U. 《Journal of Thermal Analysis and Calorimetry》1999,56(3):1191-1195
To meet the need for studies of anaerobic microbial and animal cell cultures involving much lower heat effects as compared
to aerobic microbial cultures, a bench scale calorimeter, Bio-RCl, has been improved for achieving a higher long-term sensitivity.
This newly improved Bio-RCl was used for heat measurement of anaerobic growth of Lactobacillus helveticus. The results showed
that the bench-scale calorimetry has powerful potential for on-line monitoring and control of anaerobic bioprocesses as well
as fundamental studies, such as stoichiometry, thermodynamics and kinetics of cellular growth.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
960.
离子对生成反应微观动力学的理论和实验研究有助于从本质上揭示气相、液相及上层空间大气化学反应机理.实验上已经发展到用激光-交叉分子束技术研究其态-态过程;理论上则主要是采用准经典轨迹法. 相似文献