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991.
集值映射图的广义相依导数与真有效解的最优性条件 总被引:1,自引:0,他引:1
本文提出了集值映射图的SP-相依导数的概念,利用这个概念,给出了集值向量优化问题两种真有效解的最优性条件. 相似文献
992.
Litov and Anderson after various considerations suggested a four constant potential function for a-Se as well as a-As2S3. Hence we also used a four constant potential function with the sole purpose of applying this potential function to obtain
several acoustic, thermodynamic and other properties. We calculated several acoustic properties of a-Se like second order
elastic constants (SOECs), their pressure derivatives, the longitudinal and transverse Grüneisen constant by two different
methods, phonon frequencies, absorption band position through the use of Nath-Smith-Delaunay’s equation, and the thermodynamic
properties like heat capacity, bulk modulus, thermal Grüneisen constant, the pressure derivative of the bulk modulus (dK
T/dP=C
1), the pressure derivative ofC
1 which is related to Anderson-Grüneisen parameter, pressure derivative of Grüneisen constant namelyγ′
g
which is related to second Grüneisen constant, characteristics of phonon frequencies, potential energy function through the
use of fitted parameters and third order elastic constants. Finally we calculatedK
T at the reduced density ofρ/ρ
0=1.1.K
T is obtained from the potential function with the fitted parameters. In all the above cases the calculated values are found
to be in good agreement with experiment wherever available. In this connection it is important to point out that we eliminated
‘C’ a constant in the potential function using the equilibrium condition as was done by Litovet al in a-Se and Gerlichet al in the case of a-As2S3 as all amorphous substances are isotropic as mentioned by several authors. We contemplate to calculate several other properties
for a-Se and a-As2S3 and present them at a later stage. 相似文献
993.
Shu Xian MENG Ya Qing FENG Wen Jin LI Cai Xia YIN Jin Ping DENG 《中国化学快报》2006,17(7):981-984
Chitosan, which is easily derived from chitin by N-deacetylation. It is well known that hypercholesterolemia has been identified as a major risk factor in the development of atherosclerosis and its clinical sequelae like coronary heart disease and myocard… 相似文献
994.
1INTRODUCTIONHeterocyclicketeneaminalsareversatilestartingmaterialsforthesynthesisofawidevarietyofnewheterocyclesandfusedheterocycles.Thus,thesynthesisandre-actionofheterocyclicketeneaminalshavegivenrisetomuchattention[18i.Recentlynitrationofheterocyclicketeneaminalswasstudied[9i.Wehavepreparedhexahydro-2-(nitro-benzoylmethylene)pyrimidi(1).ItscrystalstructurehasbeendeterminedbyX-raydiffractionmethodandthemolecularstructureisdiscussed.2EXPERIMENTALThesinglecrystalofhexahydro-2-(nitr… 相似文献
995.
996.
In this article, multivariate density expansions for the sample correlation matrix R are derived. The density of R is expressed through multivariate normal and through Wishart distributions. Also, an asymptotic expansion of the characteristic function of R is derived and the main terms of the first three cumulants of R are obtained in matrix form. These results make it possible to obtain asymptotic density expansions of multivariate functions of R in a direct way. 相似文献
997.
应用钛宝石可调谐脉冲激光,在波长为691nm、脉冲宽度为10ns的条件下,研究了新型富勒烯叠氮乙酰氨衍生物(N-acetamide1,2-dihydro-1,2-azafulerene[60])的光限幅特性。 相似文献
998.
Qian Rong LI* Sha YANG Structure Research Laboratory University of Science Technology of China Hefei 《中国化学快报》2003,(11)
Functionalization by cycloaddition reactions1 represents a useful strategy to modify fullerenes1,2. Stable cycloadducts are interesting in regarding to the development of new materials with unique physical properties or biological activities3. One of the typical reactions is the cycloadditions of C60 with azide compounds. Wudl and Miyata et al. reported that C60 reacted with alkyl azides4 or benzyl azides5 to give the same kind of adduct azafulleroids with an opened 6,5-ring junction by th… 相似文献
999.
Two new dibenzyltin bisditiocarbamates(PhCH2)2 Sn(S2CNEt2)2(1) and (PhCH2)2 Sn(S2CNC4H8)2(2) were synthesized by the reaction of dibenzyltin dichloride with dithiocarbamates and characterized by elemental analysis ,IR,^1H NMR and MS spectra.The crystal structures were determined by X-ray single crystal diffraction analysis.In both complexes,the tin atom is six-coordinated in a distorted octahedral configuration.In the crystals of 1,the molecular packing in unit cell reveals that the two adjacent molecules are symmetrically linked to each other in dimers by two Sn S interactions of 0.3816nm.In the crystals of 2,the molecules are packed in the unit cell in one-dimensional chain structure linked by weaker intermolecular S S conmtacts. 相似文献
1000.
XiLIFENG 《高校应用数学学报(英文版)》1997,12(4):483-492
For real-valued functions defined on Cantor triadic ,set. a derivative with corresponding formula of Newton-Leihniz‘s type is given In particular, for the self-simltar functions and alter-nately jumping functions defined in this paper, their derivative and exceptional sets are studied ac-curately by using ergodic theory on Е2 and Duffin-Scbaeffer‘s theorem coneerning metric diophan-tine approximation. In addition, Haar basis of L2(Е2) is constructed and Flaar expansion of stan-drd self-similar function is given. 相似文献