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INFlUENCE OF 2-BUTYNE-1,4-DIOl ON THE STRUCTURE AND PERFORMANCE OF THE Co-Ni AllOY PlATED BY ElECTRODEPOSITION

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Acta Metallurgica Sinica(English letters) 2008年第1期21卷 50-56页

作者： S.l. Wang l.l. Hong W.W. Yu Department of Applied Chemistry College of Materials Science and Engineering Huaqiao University Quanzhou 362021 China

The effect of 2-butyne-1, 4-diol （BD） on the deposition behavior of the Co-Ni alloy was investigated by linear sweep voltammetry. The results showed that BD could prevent the deposition of the Co-Ni alloy. The effect of BD concentration in the sulfate plating bath, on the structure of the Co-Ni deposit was studied by energy dispersive x-ray spectroscopy, scanning electron microscope, and X-ray diffraction, respectively. As a result, BD could smoothen the deposit surface and decrease the diameter of the grain, but too much of BD was not good for the size of the grain. In general, a hexagonal close-packed （hcp） phase of the Co-Ni alloy, with a preferentially oriented （110） plane, was prepared by electrodeposition in the presence of BD. The Co-Ni alloy as a catalyst for the electro-oxidation of ethanol in alkaline medium was investigated by cyclic voltammetry. The deposit plated from the bath containing BD possessed better electro-oxidation of ethanol performance compared with that of the deposit plated from only the sulfate plating bath, but too much of BD was not beneficial for catalytic activity. The Co-Ni film was suitable as a magnetic recording material.

关键词： Co-Ni 2-butyne-1, 4-diol (BD) Electrodeposition Electro-oxidation ethanol Magnetic property

Universal properties of relaxation and diffusion in condensed matter

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Chinese Physics B 2017年第1期26卷 70-85页

作者： K l Ngai State Key laboratory of Metastable Materials Science and Technology. Yanshan University Qinhuangdao 066004 China

By and large the research communities today are not fully aware of the remarkable universality in the dynamic properties of many-body relaxation/diffusion processes manifested in experiments and simulations on condensed matter with diverse chemical compositions and physical structures. I shall demonstrate the universality first from the dynamic processes in glass-forming systems. This is reinforced by strikingly similar properties of different processes in contrasting interacting systems all having nothing to do with glass transition. The examples given here include glass-forming systems of diverse chemical compositions and physical structures, conductivity relaxation of ionic conductors（liquid, glassy, and crystalline）,translation and orientation ordered phase of rigid molecule, and polymer chain dynamics. Universality is also found in the change of dynamics when dimension is reduced to nanometer size in widely different systems. The remarkable universality indicates that many-body relaxation/diffusion is governed by fundamental physics to be unveiled. One candidate is classical chaos on which the coupling model is based, Universal properties predicted by this model are in accord with diverse experiments and simulations.

关键词： many-body relaxation/diffusion universal dynamics coupling model classical chaos

From PAWP to ＂Pop＂： opening,up new pathways to fatherhood

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Asian Journal of Andrology 2015年第3期17卷 443-444页

作者： Melissa l Vadnais George l Gerton Center for Research on Reproduction and Women's Health Perelman School of Medicine University of Pennsylvania Philadelphia PA 19104-6160 USA

Infertility remains a significant problem for many couples. Approximately one in seven couples who attempt to conceive will fail to do so within 1 year. In about 65% of these cases, there is a male component of infertility.1 Despite normal semen parameters, the etiology of infertility remains uncertain in more than 50% of couples.2 Defects in sperm proteins and/ or structures may underlie certain cases of male infertility. Although many men would like to be called ＂Pop＂, ＂Dad＂, or ＂Papa＂, those who are classified with idiopathic male infertility have few options for becoming fathers. Recent studies by Aarabi et al.3 may open the door to new therapies.

关键词： @@

What′s new with the XYZ mesons?

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Chinese Physics C 2008年第6期32卷 455-462页

作者： S.l.Olsen Institute of High Energy Physics Chinese Academy of Sciences

I review some of the recent experimental results on the so-called XYZ mesons.

关键词： charmonium multiquark mesons quark-gluon hybrids

Azo Dye Doped Polymer Films for Nonlinear Optical Applications

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Chinese Journal of Polymer Science 2014年第5期32卷 650-657页

作者： l.Guru Prasad Department of Science & Humanities M.Kumarasamy College of Engineering

Azo dye doped polymer films were prepared on glass substrates using spin-coating technique. FTIR, UV-Vis spectra and Pl measurements were recorded to characterize the structure of the metanil yellow doped PVA films. Surface morphology and thickness of the films were studied using AFM and FESEM. The magnitude of both real and imaginary parts of third-order nonlinear susceptibility χ3 of metanil yellow were determined by the Z-scan technique. The nonlinear refractive index n2 and the nonlinear absorption coefficient β of the azo dye doped polymer films were calculated respectively. The real part of the third-order susceptibility χ3 is much larger than its imaginary part indicating that the third-order optical response of the metanil yellow doped PVA films is dominated by the optical nonlinear refractive behavior.

关键词： Azo dye PVA Nonlinear optical materials.

Detailed Analysis of Quantum Phase Transitions Within the u(2) Algebra

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Communications in Theoretical Physics 2010年第10期54卷 589-593页

作者： l.Fortunato l.Sartori Dipartimento di Fisica“G.Galilei”and INFN the ECT Europen Center for Theoretical Nuclear Physics CISAS G.Colombo

We analyze in detail the quantum phase transitions that arise in models based on the u(2) algebraicdescription for bosonic systems with two types of scalar *** we discuss the quantum phase transition thatoccurs in hamiltonians that admix the two dynamical symmetry chains u(2)  u(1) and u(2)  so(2) by diagonalizingthe problem exactly in the u(1) *** we apply the coherent state formalism to determine the energy *** we show that a quantum phase transition of a different nature, but displaying similar characteristics, may arisealso within a single chain just by including higher order terms in the hamiltonian.

关键词： algebraic models lie algebra quantum phase transitions lipkin model

How will biomining be applied in future?

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中国有色金属学会会刊：英文版 2008年第6期18卷 1302-1310页

作者： C.l.BRIERlEY Brierley Consultancy llC P.O.Box 630012Highlands Ranch

这篇论文在全世界考察商业 biomining 操作的当前的地位，识别作为一种处理技术驾驶 biomining 的选择的因素，描述挑战到利用这些革新，并且与 biomining 的未来的讨论得出结论。Biomining 商业地用设计垃圾场，堆和搅动的坦克被使用... 详细信息

这篇论文在全世界考察商业 biomining 操作的当前的地位，识别作为一种处理技术驾驶 biomining 的选择的因素，描述挑战到利用这些革新，并且与 biomining 的未来的讨论得出结论。Biomining 商业地用设计垃圾场，堆和搅动的坦克被使用。克服阴沉的费用的技术挑战，处理在矿的低档，低质量、复杂的矿石和利用存在大写的投资要求微生物引起的活动和创新工程的更好的理解。克服 biomining 广告挑战必要改进采矿 company/biomining 改革者合作和知识产权控制。

关键词：生物采矿生物浸取应用技术研究

Energy and momentum of rotating frames in tetrad gravity

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Chinese Physics B 2011年第10期20卷 101-111页

作者： Gamal G l Nashed Mathematics Department Faculty of Science Ain Shams University

Within the framework of the tetrad formulation of general relativity theory, we compute the total energy and momentum of four rotating frames using the gravitational energy-momentum 3-form. We show how the effect of inertia always makes the total energy divergent. We use a natural regularization method to obtain physical values for the total energy of the system and show how it works on a number of explicit examples. We also show by calculation that inertia has no effect on the momentum components.

关键词： teleparallel gravity, energy-momentum WeitzenbSck connection, regularization telepar-allelism

Nanoscale 3D ordered polymer networks

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Science China Chemistry 2018年第1期61卷 25-32页

作者： Edwin l. Thomas Department of Materials Science and NanoEngineering Rice University Houston TX 77030 USA

Structures having nanoscale 3D geometries are valuable as multifunctional materials, where multi-continuous microphases can synergistically influence mechanical, optical, transport and other properties. Such very high interface surface to volume ratio structures occur in a variety of materials including natural materials such as butter fly wings and sea urchin exoskeletons and in synthetic self-assembled structures such as surfactant/water systems and block polymers. Quantitative morphological characterization of such complex geometric structures is quite challenging. Unit cell sizes range from 10-300 nm with corresponding feature sizes on the 2-50 nm scale. Since these nanoscale network structures are bicontinuous, when one constituent is removed, the structure is still self supporting. Removal of one component produces a nanoporous material that may be in-filled with another component, or the surfaces of the nanopores can be coated with ultra-thin layers by atomic layer deposition to offer multiftmctional capabilities. Due to the ability to individually tailor the properties of the network（s） and matrix, for example, to create strong dielectric or impedance contrast, such spatially periodic structures are excellent for the interference of waves （electromagnetic for photonic applications and acoustic for phononic applications） that can lead to bandgaps and hence the control of wave propagation in the material. This mini-review will focus on networks formed by bottom up self assembly of block polymers. In addition to structural issues, we emphasize the special physical properties related to bi- or tri-continuous networks.

关键词： self assembly block polymer network morphologies bicontinuous