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991.
M. Meanti A. H. G. Rinnooy Kan L. Stougie C. Vercellis 《Mathematical Programming》1990,46(1-3):237-247
The optimal solution value of the multiknapsack problem as a function of the knapsack capacities is studied under the assumption that the profit and weight coefficients are generated by an appropriate random mechanism. A strong asymptotic characterization is obtained, that yiclds a closed form expression for certain special cases.This research was partially supported by NSF Grant ECS-83-16224, and MPI Project Matematica computazionale. 相似文献
992.
V. Dobric 《Journal of Theoretical Probability》1990,3(4):489-496
LetB be a Banach space with the Radon-Nikodym property and (S, , ) a probability space. Then anf: SB satisfies the strong law of large numbers if and only if there exists a Bochner integrable functionf
1 and a Pettis integrable functionf
2,f
2f
2=0 in the Glivenko-Cantelli norm, such thatf=f
1+f
2. The composition is unique. 相似文献
993.
Hisayoshi Kobayashi Masaru Yamaguchi Satohiro Yoshida 《Theoretical chemistry accounts》1982,60(5):391-398
A new method is presented to analyze the various interactions in reaction systems. The method is especially suited for large and strongly interacting systems where other analyzing methods are not practical. The method could isolate the particular interaction from the whole interaction by a procedure termed the partial diagonalization of the bond order matrix. The usefulness of the method is exemplified by the adsorption of CO on Pt and W surfaces. The interactions on the W surface are much stronger than those on the Pt surface, which is consistent with the experimental data. The role of individual interactions for the weakening of the C-O bond and the formation of the Pt-C and W-C bonds is discussed separately. 相似文献
994.
Large-scale massively parallel molecular dynamics (MD) simulations of the human class I major histocompatibility complex (MHC) protein HLA-A*0201 bound to a decameric tumor-specific antigenic peptide GVYDGREHTV were performed using a scalable MD code on high-performance computing platforms. Such computational capabilities put us in reach of simulations of various scales and complexities. The supercomputing resources available for this study allow us to compare directly differences in the behavior of very large molecular models; in this case, the entire extracellular portion of the peptide-MHC complex vs. the isolated peptide binding domain. Comparison of the results from the partial and the whole system simulations indicates that the peptide is less tightly bound in the partial system than in the whole system. From a detailed study of conformations, solvent-accessible surface area, the nature of the water network structure, and the binding energies, we conclude that, when considering the conformation of the alpha1-alpha2 domain, the alpha3 and beta2m domains cannot be neglected. 相似文献
995.
Ute Werner Walter M. Müller Hans-Willi Losensky Thomas Merz Fritz Vögtle 《Journal of inclusion phenomena and macrocyclic chemistry》1986,4(4):379-385
The synthesis of the new host molecule1b is described. Its complexation properties towards 1,8-ANS as a guest are reported. Compared to the monomacrocyclic host molecules2c and2e, the complex stabilities of1b with ANS as a guest are particularly higher, suggesting that the macrobicyclic host forms a better fitting niche to allow the nestling of guest molecules in solution. 相似文献
996.
高吸附性能油焦活性炭的制备和性能研究 总被引:8,自引:0,他引:8
用油焦为原料,在高温下加入适量活化剂进行活化制备活性炭,通过测定其BET比表面积和亚甲基蓝脱色能力,选出最佳活化剂。研究了活化温度、活化时间以及活化剂用量对BET比表面积和亚甲基蓝脱色能力的影响,得到活化的最佳工艺过程:活化温度为800℃、活化时间为1h以及活化剂用量为1:1。用双柱定容容量法测定了本实验制备的活性炭对甲烷的吸附量,与常用活性炭比较,是其吸附量的5倍左右。 相似文献
997.
废轮胎热解炭的分析及其活化特性的研究 总被引:1,自引:5,他引:1
用常规分析方法分析了废轮胎热解炭的成分和性质,用X射线能谱分析法、压汞法、N2吸附法等测定了热解炭的孔隙结构特性,并用CO2、含2%氧气的氮气流和水蒸气等活化气体对热解炭进行活化方面的研究。结果表明,热解炭灰分和硫含量比较高;两种不同粒径热解炭的比孔容积均在r≈25 nm处有最大值;在相同活化时间和活化剂流速下,温度越高,活化炭烧失率越大,比表面积也越大;在一定温度和活化剂流速下,烧失率和比表面积随着活化时间的增加而增大;对所有试验工况,烧失率越大,活化炭比表面积也越大。总体上水蒸气活化炭与CO2的活化效果较好,而含2%O2的氮气流活化的效果则次之。活化炭与商业活性炭的比较显示,前者具有较发达的孔隙结构,在进行大分子物质吸附时,具有替代商业活性炭的潜力。 相似文献
998.
999.
Seong-Ho Choi Jae-Wan Seo Sang-Il Nam Mu-Sang Lee Kwang-Pill Lee 《Journal of inclusion phenomena and macrocyclic chemistry》2001,40(4):279-283
FT-Raman spectra of 2-, 3-, and 4-chlorostyrene included in-cyclodextrin (CD),glycerol ether -CD, -CD,sulfated -CD, andglycerol ether -CD were recorded.In the inclusion complexes, the area of the vinyl(C=C) band decreased remarkably, whereasthe area of the phenyl (C=C) band increasedcompared to those of liquid 2-, 3-, and 4-chlorostyrene,respectively. From the results, the inclusion structures of2-, 3-, and 4-chlorostyrene were discussed. 相似文献
1000.
Jacek Rynkowski Anna Kamierczak Aleksandra Pramowska-Wilanowska Tadeusz Paryjczak 《Reaction Kinetics and Catalysis Letters》1996,58(1):169-175
Thermal treatment and the addition of lithium influence the surface area of the oxides SiO2, Al2O3 and MgO. A calcination temperature 1073 K causes a significant decrease of the surface area of SiO2 and Al2O3; the same is not observed in case of MgO. Systems Li/MgO and Li/SiO2 are characterized by a much smaller specific surface area than pure oxides thermally treated at the same temperature. 相似文献