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991.
Let (R, m) be a Cohen-Macaulay local ring of dimension d, I an mprimary ideal and K an ideal containing I. Assuming that I has minimal (almost minimal) mixed multiplicity with respect to K, we get some results on the Hilbert coefficients of fiber cones. 相似文献
992.
Chang-jian ZHAO Department of Information Mathematics Sciences College of Science China Jiliang University Hangzhou China 《中国科学A辑(英文版)》2007,50(9):1347-1360
In this paper,we first introduce a concept of L_p-dual Quermassintegral sum function of convex bodies and establish the polar projection Minkowski inequality and the polar projection Aleksandrov-Fenchel inequality for L_p-dual Quermassintegral sums.Moreover,by using Lutwak's width-integral of index i,we establish the L_p-Brunn-Minkowski inequality for the polar mixed projec- tion bodies.As applications,we prove some interrelated results. 相似文献
993.
D. E. Hawkinson E. Kohout R. E. Fornes Richard D. Gilbert 《Journal of Polymer Science.Polymer Physics》1991,29(13):1599-1605
There is little or no trifluoroacetylation of cellulose dissolved in TFA-CH2Cl2 admixtures. Both cellulose and cellulose triacetate (CTA)are slowly degraded in the solvent. Cellulose forms a mesophase as low as 4%(w/w)concentration, but CTA has a much higher critical concentration, 20% (w/w), in TFA-CH2Cl2. The cellulose behaves as a rigid rod in TFA-CH2Cl2 (70/30v/v) and its persistence length calculated using the lattice model approximates its chain length, presumably due to extensive interaction with the solvent. As expected, due to low polymer-solvent interactions, the persistence length of CTA in TFA-CH2Cl2 is only one-fourth the chain length. 相似文献
994.
M. Larsen 《K-Theory》1995,9(2):173-198
We describe an approach to computing cyclic homology suited to ground rings of characteristicp or mixed characteristic. We illustrate the method by computing HC for coordinate rings of affine plane curves and for maximal orders of semisimple algebras.Partially supported by NSF Grant No. DMS-8807203 and NSA Grant No. MDA 904-92-H-3026. 相似文献
995.
Thermogravimetric analysis was applied to the characterization of the porosity of silica gels. Results from thermogravimetric method are compared with those obtained from the nitrogen method. The consistency of the parameters characterizing the porous structure of silica gels derived from the data of various methods is satisfactory. 相似文献
996.
In this work, we are interested in the numerical approximation of an eigenvalue problem arising from the computation of guided modes in integrated optics waveguides which are particular cases of open waveguides. 相似文献
997.
998.
The classical deterministic scheduling problem of minimizing the makespan on unrelated parallel processors is known to be NP-hard in the strong sense. Given the mixed integer linear model with binary decision variables, this paper presents heuristic algorithms based on partial enumeration. Basically, they consist in the construction of mixed integer subproblems, considering the integrality of some subset of variables, formulated using the information obtained from the solution of the linear relaxed problem. Computational experiments are reported for a collection of test problems, showing that some of the proposed algorithms achieve better solutions than other relevant approximation algorithms published up to now. 相似文献
999.
Shiva Raj Sarala Devi Ch. Seshikala G. Ram Reddy M. G. 《Journal of Chemical Sciences》1992,104(1):15-20
The proton ligand constants of 4-chloro and 4-amino picolinic acid N-oxide and the formation constants of corresponding binary
chelates of Cu(II) and Ni(II) have been measured at 30°C and 0.1M ionic strength in varying percentages of dioxane-water,
acetone-water, ethanol-water and isopropanol-water. The results are discussed with reference to the change in dielectric constants
of water in the presence of organic solvent, change in the structuredness of water, change in hydrogen bonding ability of
the organic solvent in water, solvent basicity and proton solvation by organic solvent. The values have been compared with
aqueous and mixed aqueous systems of picolinic acid N-oxide and 4-methoxy picolinic acid N-oxide. 相似文献
1000.
FCC油浆抽提分离产物结构组成分析 《燃料化学学报》2003,48(8):937-941
以切尾FCC油浆为原料,采用DMF和反抽提剂的复配溶剂进行抽提分离,对FCC油浆及其抽提产物的物性和组成进行了分析表征。结果表明,复配溶剂可以较好地将FCC油浆分离成以芳香烃为主的抽出相和以饱和结构为主的抽余相,在抽出油收率为58.5%时,抽出油芳香分含量80.5%,芳碳率为73.82%,所含芳烃以二环、三环和四环为主,可以作为橡胶填充油和增塑剂等的原料;抽余油饱和分含量高达90%以上,芳碳率只有2.38%,基本不含杂原子,可以作为优良的催化裂化原料。溶剂抽提可以使低附加值的FCC油浆得到较好的利用。 相似文献