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1.
介绍了南开大学国家物理学基础科学研究人才培养基地在十多年的建设中,通过多元化的教学手段提高学生的学习自主性,通过加强科研训练提高物理人才综合素质的经验和取得的成果.  相似文献   
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We provide some inequalities and integral inequalities connected to the Jensen-Hadamard inequalities for convex functions. In particular, we give some refinements to these inequalities. Some natural applications and further extensions are given.
Sunto Forniamo alcune diseguaglianze e diseguaglianze integrali connesse alle dise-gueglianze di Jensen-Hadamard per funzioni convesse. In particolare, diamo qualche miglioramento di queste diseguaglianze. Alcune applicazioni naturali ed ulteriori estensioni sono date.
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In this paper, we generalize Hu Ke's sharpness of Hölder's inequality. As application, the obtained result is used to improve the well-known Opial-Olech inequality.  相似文献   
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We investigate function spaces of generalised smoothness of Besov and Triebel–Lizorkin type. Equivalent quasi-norms in terms of maximal functions and local means are given. An atomic decomposition theorem for this type of spaces is proved. Mathematics Subject Classification (2000) 46E35  相似文献   
6.
Two extensions of the univariate Gini index are considered:RD, based on expected distance between two independent vectors from the same distribution with finite meanμ d; andRV, related to the expected volume of the simplex formed fromd+1 independent such vectors. A new characterization ofRDas proportional to a univariate Gini index for a particular linear combination of attributes relates it to the Lorenz zonoid. TheLorenz zonoidwas suggested as a multivariate generalization of the Lorenz curve.RVis, up to scaling, the volume of the Lorenz zonoid plus a unit cube of full dimension. Whend=1, bothRDandRVequal twice the area between the usual Lorenz curve and the line of zero disparity. Whend>1, they are different, but inherit properties of the univariate Gini index and are related via the Lorenz zonoid:RDis proportional to the average of the areas of some two-dimensioned projections of the lift zonoid, whileRVis the average of the volumes of projections of the Lorenz zonoid over all coordinate subspaces.  相似文献   
7.
In this paper we prove that iff ∈ C([-π,π]2) and the function f is bounded partial p-variation for some p ∈ [1, ∞), then the double trigonometric Fourier series of a function f is uniformly (C;-α,-β) summable (α β< 1/p,α,β> 0) in the sense of Pringsheim. If α β≥ 1/p, then there exists a continuous function f0 of bounded partial double trigonometric Fourier series of fo diverge over cubes.  相似文献   
8.
We say that f is reciprocally convex if x?f(x) is concave and x?f(1/x) is convex on (0,+∞). Reciprocally convex functions generate a sequence of quasi-arithmetic means, with the first one between harmonic and arithmetic mean and others above the arithmetic mean. We present several examples related to the gamma function and we show that if f is a Stieltjes transform, then −f is reciprocally convex. An application in probability is also presented.  相似文献   
9.
Equilibrium data for the adsorption of phenolic compounds, i.e., phenol, p-cresol, p-chlorophenol and p-nitrophenol from aqueous solutions by a water-compatible hypercrosslinked polymeric adsorbent (NJ-8) within temperature range of 283-323 K were obtained and correlated with a Freundlich-type of isotherm equation, so that equilibrium constants KF and n were obtained. The capacities of equilibrium adsorption for all the four phenolic compounds on the NJ-8 from aqueous solutions are around 2 times as high as those of Amberlite XAD-4, which may be attributed to the unusual micropore structure and the partial polarity on the network. The values of the enthalpy (always negative) are indicative of an exothermic process, which manifests the adsorption of all the four phenolic compounds on the two polymeric adsorbents to be a process of physical adsorption. The negative values of free energy change show that the solute is more concentrated on the adsorbent than in the bulk solution. The absolute free energy values of adsorption for NJ-8 are always higher than those for Amberlite XAD-4, which indicates that phenolic compounds are preferentially adsorbed on NJ-8. The negative values of the adsorption entropy are consistent with the restricted mobilities of adsorbed molecules of phenolic compounds as compared with the molecules in solution. The adsorption entropy values of phenolic compounds for NJ-8 are lower than those for Amberlite XAD-4, which means the micropores of NJ-8 require more orderly arranged adsorbate.  相似文献   
10.
In this paper, superhigh reproductive rate strains of MEV with titre more than HA8192* or TCID50 log9.7 10 have been achieved both by cultivation in cell lines with different susceptibility to MEV and by isolating and identifying in field by the author. The systematic tests proved that S18 and L12 strains of MEV are the best strains for vaccine preparation. In this study, the best means for the tissue cultivation of MEV and the most advanced technological process for the production and detection of serum-free cell-cultured MEV fluids with super-high HA titre in batches in large quantities have been established for the first time. Optimum conditions for MEV inactivation were determined, and safe and effective inactivated vaccines with mineral oil or A1(OH)3 gel adjuvant were successfully prepared with serum-free cell-cultured MEV fluids. Both vaccines with different adjuvants can be manufactured in batches in large quantities and have been widely used all over China since 1986. The change laws of the imm  相似文献   
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