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81.
Optimality for set functions with values in ordered vector spaces   总被引:3,自引:0,他引:3  
Let (X, , ) be a finite atomless measure space,L a convex subfamily of , andY andZ locally convex Hausdorff topological vector spaces which are ordered by the conesC andD, respectively. LetF:LY beC-convex andG:LZ beD-convex set functions. Consider the following optimization problem (P): minimizeF(), subject to L andG() D . The paper generalizes the Moreau-Rockafellar theorem with set functions. By applying this theorem, a Kuhn-Tucker type optimality condition and a Fritz John type optimality condition for problem (P) are established. The duality theorem for problem (P) is also studied.This work was partially supported by National Science Council, Taipei, Taiwan. This paper was written while the first author was visiting at the University of Iowa, 1987-88.The authors would like to express their gratitude to the two anonymous referees for their valuable comments. Also, they would like to thank Professor P. L. Yu for his encouragement and suggestions which improved the material presented here considerably.  相似文献   
82.
本文用钢塑性有限元方法,对平辊同步和异步薄件轧制进行了计算,求出力能参数、速度场和应力应变场,并对二者加以比较。之后,又对异步轧制的特征进行了分析。  相似文献   
83.
纳米氧化铜的制备及常温脱硫效能研究   总被引:3,自引:0,他引:3  
闫波  王新  邵纯红  李芬  姜安玺 《无机化学学报》2007,23(11):1869-1874
采用硝酸铜为原料、氢氧化钠溶液为沉淀剂、使用体积比为1∶1的乙醇-水溶液为分散剂的直接沉淀法制备,通过改变工艺条件得到了三种纳米氧化铜产品,平均粒径分别为25.63,10.74和7.57 nm。采用TG-DTA、FIR、XRD和TEM等对纳米氧化铜进行表征。对产品的常温脱硫活性进行了穿透试验,并与已开发的其他常温精脱硫产品进行了比较,结果表明纳米氧化铜应用于H2S脱硫,可在常温条件下具有优异的脱硫活性,对H2S的脱除精度可以达到0.05 mg·m-3以下。经过优选,产品在3 000 h-1空速下穿透硫容达到25.3%,高于同类型的其他脱硫剂产品。  相似文献   
84.
The vibrational wavenumbers and the fundamental modes of 2,2′-biquinoline were obtained by density functional theory (DFT) with the B3LYP functional using the 6-31G(d,p) basis set. The calculated wavenumbers were scaled by a single factor of 0.965 to correct them for vibrational anharmonicity, but the force constants were overestimated. Normal coordinate analysis of the molecule was also carried out by using the force field of the quinoline molecule and the force field parameters of quinoline are shown to be transferable to 2,2′-biquinoline. The potential energy distribution associated with the normal modes is also given. The theoretical wavenumbers are found to be in good agreement with the experimental data.  相似文献   
85.
Synthesis and Structure of Ag_3PSe_4   总被引:1,自引:0,他引:1  
The title compound Ag3PSe4 was synthesized by the reaction of Ag powder,P2Se5 and Se in a molar ratio of 1:1:1 at 500℃ and structurally characterized by X-ray crystallography.The crystal belongs to orthorhombic,space group Pmn21 with cell parameters:a=7.689(4),b=6.660(3),c=6.379(4)A,V=326.7(3)A^3,Z=2,Dc=6.816g/cm^3,Mr=670.42,F(000)=584,μ=31.302mm^-1,R=0.0606,wR=0.1289 and S=1.012,The 3-D structure can be regarded as constructed from the stacking of puckered Ag-P-Se honeycomb-like sheets along the c direction,in which the Ag,P and Se atoms are bonded to each other to form a chair-like six-membered ring,and the rings then build the sheets by sharing edges.  相似文献   
86.
Let X1, X2,…, be independent, identically distributed random variables. Suppose that the linear forms L1 = Σj=1ajXj and L2 = Σj=1bjXj exist with probability one and are identically distributed; necessary and sufficient conditions assuring that X1 is normally distributed are presented. The result is an extension of a theorem of Linnik (Ukrainian Math. J.5 (1953), 207–243, 247–290) concerning the case that the linear forms L1 and L2 have a finite number of nonvanishing components. This proof only makes use of elementary properties of characteristic functions and of meromorphic functions.  相似文献   
87.
The Fourier transform far infrared spectra of oxalate hydrates of whole rare-earth series except Pm and Sc are investigated in the range of 100-400 cm~(-1). The assignment of vibrational frequencies is made on the basis of normal coordinate analysis using our NORVIB program. The model used for the hghter elements of the lanthanide series (La to Eu) is based on the crystal structure of Nd_2(C_2O_4)_3. 10H_2O, in which each lanthanide ion is surrounded by nine O atoms, six from three oxalate ions and three from Water molecules.The model adopted for the heavier elements of the lanthanide series (Gd to Lu) and Ytterbium is based on the crystal structure of Yb_2(C_2O_4)_3· 6H_2O, in which each ion is surrounded by eight atoms, six from three oxalate ions and two from water molecules. The variation of the metal-ligand frequencies and force constants with the atomic numbers of lanthanides is plotted and discussed.  相似文献   
88.
分析了二组分混合物的3种混合/分离状态及在完全混合时发生连续相转变的极限组成。提出一个判别非等密度体系混合/分离状态的法则与确定混合物空隙率简易可行的随意松散堆积方法。  相似文献   
89.
In this study, local least squares (LLS) and principal component analysis (PCA) were applied to deal with the disturbances in a data set of chromatographic fingerprints after necessary data transformations. It has been demonstrated that PCA with standard normal variate (SNV) transformation of data led to meaningful classification of 33 different Erigeron breviscapus herbal samples. The result was also corroborated by variance squares discriminant method. The quality of herbal objects was further evaluated, and the causes of this fact have been explained from a chemical point of view. At the same time, it implied an idea for qualitative evaluation of the herbal objects with a common class pattern of chromatographic fingerprints.  相似文献   
90.
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