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Metallated conjugation in small-sized-molecular donors for solution-processed organic solar cells

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science China Chemistry 2015年第2期58卷 347-356页

作者： Chaohua Cui Yunye Zhang Wallace C.h.Choy hua Li Wai-Yeung Wong Institute of Molecular Functional Materials Department of Chemistry and Institute of Advanced Materials Hong Kong Baptist University Department of Electrical and Electronic Engineering The University of Hong Kong College of Life and Environmental sciences & Beijing Engineering Research Center of Food Environment and Public health Minzu University of China hKBU Institute of Research and Continuing Education Shenzhen Virtual University Park

Four metallated conjugated oligothiophenes, s-1, s-2, s-3 and s-4, with platinum（II） aryleneethynylenes as the electron-rich building block were synthesized to investigate their physicochemical and photovoltaic properties. These small molecules possess fairly low-lying hOMO energy levels which match with the LUMO energy level of the electron acceptor PC70BM （[6,6]-phenyl-C71-butyric acid methyl ester）. Using the simple process of spin-coating solution fabrication technique, s-I：PC70BM （1：4, w/w） based organic solar cells exhibiting a high Voc of 0.913 V, with a PCE value of 0.88% were developed. In contrast, the OsC device based on s-2：PC70BM （3：7, w/w） displayed a higher PCE of 1.59% with a higher Jsc value of 5.89 mA cm^-2. The device based on s-4：PCToBM （1：4, w/w） exhibited a PCE value of 1.56%, with a Voc of 0.917 V.

关键词： platinum acetylide photovoltaics organic solar cell oligothiophene

Artificial perturbation for solving the Korteweg-de Vries equation

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Journal of Zhejiang University-science A(Applied Physics & Engineering) 2006年第12期7卷 2079-2082页

作者： KhELIL N. BENsALAh N. sAIDI h. ZERARKA A. Laboratory of Physics and Applied Mathematics University Med Khider BP 145 07000 Biskra Algeria

A perturbation method is introduced in the context of dynamical system for solving the nonlinear Korteweg-de Vries (KdV) equation. Best efficiency is obtained for few perturbative corrections. It is shown that, the question of convergence of this approach is completely guaranteed here, because a limited number of term included in the series can describe a sufficient exact solution. Comparisons with the solutions of the quintic spline, and finite difference are presented.

关键词： Perturbation Taylor series Quintic spline Korteweg-de Vries (KdV) equation

Existence of Nonabelian Free subgroups in the Maximal subgroups of GLn（D）

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Algebra Colloquium 2014年第3期21卷 483-496页

作者： h.R. Dorbidi R. Fallah-Moghaddam M. Mahdavi-hezavehi Department of Mathematical sciences Sharif University of 3bchnology P.O. Box 11155-3415 Tehran Iran

Given a non-commutative finite dimensional F-central division algebra D, we study conditions under which every non-abelian maximal subgroup M of CLn （D） contains a non-cyclic free subgroup. In general, it is shown that either M contains a non-cyclic free subgroup or there exists a unique maximal subfield K of Mn（D） such that NCLn（D）（K＊） = M, K＊ △ M, K/F is Galois with Gal（K/F） ≌ M/K＊, and F[M] = in（D）. In particular, when F is global or local, it is proved that if （[D ： F], Char（F）） = 1, then every non- abelian maximal subgroup of GL1 （D） contains a non-cyclic free subgroup. Furthermore, it is also shown that GLn（F） contains no solvable maximal subgroups provided that F is local or global and n ≥ 5.

关键词： free subgroup maximal subgroup central simple algebralotion

scale dependence of direct shear tests

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Chinese science Bulletin 2009年第23期54卷 4337-4348页

作者： ZhOU Qiang shEN hayley h hELENBROOK Brian T ZhANG hongWu Department of Engineering Mechanics Dalian University of Technology Dalian 116024 China Department of Civil and Environmental Engineering Clarkson University Potsdam NY 13699-5710 USA Department of Mechanical and Aeronautical Engineering Clarkson University Potsdam NY 13699-5725 USA

Direct shear test has been widely used to measure the shear strength of soils and other particulate materials in industry because of its simplicity. however, the results can be dependent on the specimen size. The AsTM (American society for Testing and Materials) publications suggest that for testing soils the shear box should be at least ten times the diameter of the largest particle and the height of the box should be no more than half of its diameter. These guidelines are empirically based. A series of two-dimensional numerical direct shear tests are performed to investigate this scaling effect. By analyzing the bulk friction, particle translation and rotation, percentage of sliding, average volume (area) and shear strain and the evolution of the shear band, we find that the traditional guidelines for direct shear tests are questionable. scaling dependency of bulk friction on the property of granular materials is clearly present. Our current analysis points out that the scaling effects can vary significantly depending on the particle properties other than their sizes. Of all the parameters we observed, particle rotation appears to have a decisive correlation with the bulk friction. Formation of a shear band is universal. As the shearing progresses, particle rotation begins to concentrate near the shear plane. By defining the width of a shear band as the standard deviation of the distribution of translational gradient or the standard deviation of the distribution of particle rotation, quantitative evolutions of shear band are presented. Both measures of the shear band width dropped rapidly during pre-failure stage. After peak stress both measures begin to approach steady state as the bulk friction stabilizes to the residual stage. These observations suggest that structure formation inside the shear band controls the scaling effect.

关键词：直接剪切试验测试土力学土工试验

Effect of Crystallization Conditions on Polymorphic Diversity of Malic Acid Rs-Racemate

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Transactions of Tianjin University 2013年第2期19卷 86-91页

作者： Isakov A I Kotelnikova E N Kryuchkova L Yu Lorenz h st.Petersburg state University St.Petersburg 199034Russia Max Planck Institute for Dynamics of Complex Technical systems Magdeburg 39106Germany

Enantiomers （R （＋） and s（-））, Rs-racemate mixture of enantiomers） of malic acid C4h605 have been （double compound） and （R ＋ s） -conglomerate （mechanical investigated by means of X-ray diffractometry and high tern- perature X-ray diffraction method. The Rs-racemate was found to be able to form three polymorphic modifications, which we denominated as M1 （monoclinic, space group P21/c）, M2 （monoclinic, space group Cc）, and Tc （triclinic, space group P-l ）, the latter modification having been unknown before. Modification Tc was also described, and its X- ray diffraction characteristics, including interplanar spacings d, hkl indices, unit cell parameters, were defined. In addi- tion, X-ray diffraction characteristics for both reported earlier M1 and M2 monoclinic polymorphic modifications were measured with higher accuracy. The ability of Rs-racemate to form one of the above three modifications （MI, M2, and Tc） or their mixtures containing various proportions and combinations of the components （M1 ＋ M2, M1 ＋ Tc, or M2 ＋ Tc） was found to depend on the type of crystallization medium （a melt, aqueous medium, ethanol or acetone solu- tion）, crystallization rate （from 2--3 minutes to 4 months）, and crystallization temperature. heating s-enantiomer and M1 Rs-racemate up to their respective melting points （100 ℃ and 124 ℃, correspondingly） only made them undergo thermal deformations, while heating （R ＋ s） -conglomerate in the temperature range of 96--110 ℃ resulted in its.h.mogenization to form M2 Rs-racemate, which, near the melting point （118 ℃）, namely, in the range of 112-116 ℃, was transformed into MI Rs-racemate. Keywords： polvmorDhism; racemic, chiral

关键词： polymorphism racemic chiral

ON ThE COEFFICIENTs OF DIFFERENTIATED EXPANsIONs AND DERIVATIVEs OF ChEBYshEV POLYNOMIALs OF ThE ThIRD AND FOURTh KINDs

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Acta Mathematica scientia 2015年第2期35卷 326-338页

作者： Eid h.DOhA Waleed M.ABD-ELhAMEED Mahmoud A.BAssUONY Department of Mathematics Faculty of ScienceCairo University Department of Mathematics Faculty of ScienceUniversity of Jeddah Department of Mathematics Faculty of ScienceFayoum University

Two new analytical formulae expressing explicitly the derivatives of Chebyshev polynomials of the third and fourth kinds of any degree and of any order in terms of Chebyshev polynomials of the third and fourth kinds themselves are proved. Two other explicit formulae which express the third and fourth kinds Chebyshev expansion coefficients of a general-order derivative of an infinitely differentiable function in terms of their original expansion coefficients are also given. Two new reduction formulae for summing some terminating hypergeometric functions of unit argument are deduced. As an application of how to use Chebyshev polynomials of the third and fourth kinds for solving high-order boundary value problems, two spectral Galerkin numerical solutions of a special linear twelfth-order boundary value problem are given.

关键词： Chebyshev polynomials of the third and fourth kinds expansion coefficients generalized hypergeometric functions boundary value problems

XFEL data analysis for structural biology

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Frontiers of Electrical and Electronic Engineering in China 2016年第3期4卷 159-176页

作者： haiguang Liu John C. h. spence Complex systems Division Beiiin.q Computational Science Research Center Beijing 100193 China Physics Department Arizona State University Tempe AZ 85287 USA

X-ray Free Electron Lasers （XFELs） have advanced research in structure biology, by exploiting their ultra-short and bright X-ray pulses. The resulting ＂diffraction before destruction＂ experimental approach allows data collection to outrun radiation damage, a crucial factor that has often limited resolution in the structure determination of biological molecules. since the first hard X-ray laser （the Linac Coherent Light source （LCLs） at sLAC） commenced operation in 2009, serial femtosecond crystallography （sFX） has rapidly matured into a method for the structural analysis of nano- and micro-crystals. At the same time, single particle structure determination by coherent diffractive imaging, with one particle （such as a virus） per shot, has been under intense development. In this review we describe these applications of X-ray lasers in structural biology, with a focus particularly on aspects of data analysis for the computational research community. We summarize the key problems in data analysis and model reconstruction, and provide perspectives on future research using computational methods.

关键词： X-my Free Electron Laser single particle scattering serial crystallography phase retrieval orientationrecovery

Dynamic Analysis of Vibrating systems with Nonlinearities

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Communications in Theoretical Physics 2012年第2期57卷 183-187页

作者： M.Kalami Yazdi h.Ahmadian A.Mirzabeigy A.Yildirim s.h.ol of Mechanical Engineering Iran University of Science and TechnologyNarmakTehran16846Iran Department of Mechanical Engineering Amirkabir University of TechnologyHafez AveTehran 15914Iran Department of Mathematics Ege University35100 Bornova-IzmirTurkey Department of Mathematics and statistics University of South FloridaTampaFL 33620USA

The max-min approach is applied to mathematical models of some nonlinear *** models are regarding to three different forms that are governed by nonlinear ordinary differential *** this context,the strongly nonlinear Duffing oscillator with third,fifth,and seventh powers of the amplitude,the pendulum attached to a rotating rigid frame and the cubic Duffing oscillator with discontinuity are taken into *** obtained results via the approach are compared with ones achieved utilizing other *** results indicate that the approach has a good agreement with other well-known ***'s max-min approach is a promising technique and can be successfully exerted to a lot of practical engineering and physical problems.

关键词： nonlinear oscillation he's max-min approach dynamic analysis

Properties Correlations and Characterization of Athabasca Oil sands-derived synthetic Crude Oil

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Petroleum science 2007年第3期4卷 84-90页

作者： Wang Jun Zhao suoqi Xu Chunming Chung Keng h. state Key Laboratory of heavy Oil Processing China University of Petroleum Beijing 102249 China Petrochemical Institute of PetroChina Beijing 10083 China EnergyINet Calgary Alberta Canada

Narrow fractions of Athabasca oil sands-derived synthetic crude oil （sCO） from Canada were obtained by distillation at 20 ℃ to 500 ℃ and characterized. The yield and properties, such as density, refractive index, viscosity, freezing point, sulfur and nitrogen content and UOP K-index, were correlated as a function of boiling temperature （Tb）. The properties of naphtha fractions, jet fuel and diesel fractions could be predicted accurately with the correlations, which are useful for process design considerations, such as optimizing operating conditions of refinery processing units. The other key properties and characteristics of naphtha fractions, jet fuel, diesel and vacuum gas oil were also determined.

关键词： sCO properties correlation characterization