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Exact solution of Schrdinger equation with q-deformed quantum potentials using Nikiforov–Uvarov method

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Chinese Physics b 2013年第11期22卷 166-173页

作者： Falaye b.j. Oyewumi K.j. Abbas M. Theoretical Physics Section Department of Physics University of Ilorin Physics Department Kebbi State University of Science and Technology

In this paper, we present the exact solution of the one-dimensional Schrrdinger equation for the q-deformed quantum potentials via the Nikiforov-Uvarov method. The eigenvalues and eigenfunctions of these potentials are obtained via this method. The energy equations and the corresponding wave functions for some special cases of these potentials are briefly discussed. The PT-symmetry and Hermiticity for these potentials are also discussed.

关键词： Schrōdinger equation q-deformed quantum potential Woods-Saxon potential Nikiforov-Uvarovmethod

Sexual selection affects the sizes of the mammalian prostate gland and seminal vesicles

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Current Zoology 2009年第1期55卷 1-8页

作者： Matthew j. ANDERSON Alan F. dixson Conservation and Research for Endangered Species Zoological Society of San Diego School of biological Sciences Victoria University of Wellington

The accessory reproductive glands of male mammals contribute the bulk of the secretions in which spermatozoa are transported to the female tract during copulation. Despite their morphological diversity, and the chemical complexity of their products, little is known about the possible effects of sexual selection upon these glands in mammals. Here we consider the seminal vesicles and prostate glands in a sample of 89 species and 60 genera representing 8 Orders of mammals. The sizes of the accessory glands are analysed in relation to body weight and testes weight. both the seminal vesicles size and prostate size （corrected for body weight） correlate positively with relative testes size in this sample; this finding remains highly significant after application of procedures to correct for possible phylogenetic biases in the data set. The accessory reproductive glands are also significantly larger in those mammals which have large relative testes sizes, and in which the likelihood of sperm competition is greatest. These results support the hypothesis that sexual selection has played an important role in the evolution of the mammalian prostate gland and seminal vesicles.

关键词： Mammals Prostrate gland Seminal vesicles Sexual selection Sperm competition

CONTINUOUS STIFFNESS MODE NANOINDENTATION RESPONSE OF POLY(METHYL METHACRYLATE) SURFACES

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Chinese journal of Polymer Science 2013年第8期31卷 1096-1107页

作者： T. Iqbal b.j. briscoe S. Yasin P.F. Luckham Chemical Engineering Department University of Engineering & Technology Chemical Engineering Department Imperial College

Indentation is a comparatively simple and virtually nondestructive method of determining mechanical properties of material surfaces by means of an indenter inducing a localized deformation. The paper present experimental results of the load-displacement curves, the hardness and the elastic modulus data, and associated analysis for poly（methyl methacrylate）（PMMA） surfaces as a function of contact displacement. The experimental results include continuous stiffness indentations performed using constant loading rate and constant displacement rate experiments. The continuous stiffness indentation involves continuous calculation of a material stiffness, and hence hardness and elastic modulus of surfaces, during discrete loading-unloading cycles, as in a conventional indentation routine, and in a comparatively smaller time constant, The dependence of the compliance curves, the hardness, the elastic modulus and the plasticity index upon the imposed penetration depth, the applied normal load and the deformation rate are described. Tip area and load frame calibrations for the continuous stiffness indentation are also reported. The paper includes practical considerations encountered during indentation of polymers specifically at low penetration depths. The experimental results show a peculiarly harder response of PMMA surfaces at the submicron （near to surface） layers.

关键词： Nanoindentation PMMA Hardness Modulus Continuous stiffness.

Modern short stories in English

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INFLUENCE OF THE ALIGNMENT OF TiO_2 NANOPARTICLES ON OPTICAL AND STRUCTURAL PROPERTIES OF POLY(PHENYLENEVINYLENE) FILMS

1000年

作者： Robert j. dixson.

来源：畅想之星图书光盘版（南... 评论

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畅想之星图书光盘版（南通市图书馆镜像）

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Acta Metallurgica Sinica(English Letters) 2002年第1期15卷 104-108页

作者： X. ju j. Zhang b. Y. Wang b.j. Wang bSRF Institute of High Energy Physics The Chinese Academy of Sciences Beijing 100039 China Institute of Photography The Chinese Academy of Sciences Beijing 100101 China

A series of poly(phenylenevinylene) (PPV)/titanium oxide (TiO_2)nanocomposites with different contents of TiO_2 nanoparticles were prepared from mixtures of PPVprecursor and titanium butoxide ethanol solution in a sol- gel process. TEM images showed theformation of the connected network of TiO_2 nanoparticles with a higher content of TiO_2, whichresulted in the titanium butoxide hydrolyzed to form Ti organic compound. Meanwhile, the conjugationof PPV polymer chains can be interrupted by the TiO_2 network structure. The PL spectra revealedthat the emitted light of the PPV/TiO_2 nanocomposites blue shifted without fine structure and thePL intensity enhanced when the TiO_2 network formed. In the lifetime spectroscopy of positronannihilation, the structural properties of the PPV dominated the character of the nanocomposites, inwhich the formation of the omicron -Ps was presented in free volume polymer, when the content ofTiO_2 was below 10 percent. Further increasing the content of TiO_2 nanoparticle introduced muchmore vacancies, vacancy clusters and grain boundaries at their interfaces, which led to thecorresponding lifetime and intensity close to that of the nano- TiO_2 bulk materials. With the TiO_2content of 50 percent of long lifetime. These phenomena suggested that the optical and structuralproperties of the PPV/TiO_2 nanocomposites are dependent on the interfacial structure between PPVand TiO_2 nanoparticles.

关键词： PPV/TiO_2 nanocomposite the doping effect positron annihilation

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泰人起源问题的再思考

世界民族 1989年第4期 36-44页

作者： b.j.戴维申旭

本文有三重目的。首先,论述各种关于泰人故土的看法和对可以找到的这些看法的证据进行评价;第二,提供一个在该问题上的新发现的详细目录和指明对这些领域的进一步研究是必要的;第三,本人主张就泰人的仪式进行比较是再现原始泰文化的一... 详细信息

本文有三重目的。首先,论述各种关于泰人故土的看法和对可以找到的这些看法的证据进行评价;第二,提供一个在该问题上的新发现的详细目录和指明对这些领域的进一步研究是必要的;第三,本人主张就泰人的仪式进行比较是再现原始泰文化的一种方法,并提出这种再现可以提供历史和考古之间的一种重要的联系。最后,对东山文化和泰文化之间可能存在某种联系提出一些思索。

关键词：泰人东山文化起源问题东南亚相似之处新发现仪式中国南部证据印度尼西亚人