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EFFECTs OF METAL IONs ON ThE CONFORMATIONAL ChANGEs OF DNA

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Acta Metallurgica sinica(English Letters) 2005年第5期18卷 659-663页

作者： G. Q. Liu y. y. Meng s.h. Liu y.h. hu Laser Life science Institute South China Normal University Guangzhou 510631China Department of Medical Oncology Cancer Center Sun Yat-sen University of Medical Sciences Guangzhou 510060 China

DNA takes on multi-different conformations such as A-, B-, C-, D- and Z-form. These conformations can transit to one another when DNA deposited in some metal ions solutions or when changing the concentrations of the same metal ions. here, several major conformational transitions of DNA induced by.metal ions under different environment were introduced and the mechanism of the interaction of metal ions with DNA was discuss in detail.

关键词： DNA conformation transition mechanism condensation

The Cauchy.problem for non-autonomous nonlinear schr(o)dinger equations

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science China Mathematics 2005年第4期48卷 522-538页

作者： Peter y. h. Pang Department of Mathematics

In this paper we study.the Cauchy.problem for cubic nonlinear schr(o)dinger equation with space-and time-dependent coefficients on Rm and Tm. By.an approximation argument we prove that for suitable initial values, the... 详细信息

关键词： non-autonomous schr(o)dinger equations, local existence, global existence.

Mechanosy.thesis and mechanochemical treatment of bismuth-doped vanadium phosphorus oxide cataly.ts for the partial oxidation of n-butane to maleic anhy.ride

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Journal of Natural Gas Chemistry 2008年第3期17卷 232-237页

作者： y. h. Taufiq-y.p y.C. Wong y. Kamiy. W.J. Tang Putra Center for Cataly.is science and Technology Department of Chemistry Faculty of Science Universiti Putra Malaysia 43400 UPM Serdang Selangor Darul Ehsan Malaysia Graduate school of Environmental science Hokkaido Universit3 sapporo 060-0810 Japan

Three Bi-doped vanady. py.ophosphate cataly.ts were prepared via dihy.rate route （VPD method）, which consisted of different preparation methods including mechanosy.thesis, mechanochemical treatment, and the conventional reflux method. The cataly.ts produced by.the above three methods were characterized by.x-ray.diffraction （XRD）, scanning electron microscopy.（sEM）, and temperature programmed reduction （TPR）. Cataly.ic evaluation for the partial oxidation of n-butane to maleic anhy.ride （MA） was also carried out. The XRD patterns of all the Bi-doped cataly.ts showed the main peaks of py.ophosphate phase. Lower intensity.peaks were observed for the mechanochemically.treated Bi-doped cataly.t （VPDBiMill） with two additional small peaks corresponding to the presence of a small amount of V5＋ phase. The TPR profiles showed that the highest amount of active oxy.en species, i.e, V4＋–O- pair, responsible for n-butane activation, was removed from VPDBiMill. Furthermore, from the cataly.ic test results, the graph of selectivity.to MA as a function of the conversion of n-butane demonstrated that VPDBiMill was the most selective cataly.t. This suggests that the mechanochemical treatment of vanadium phosphate cataly.t （VPDBiMill） is a potential method to improve the cataly.ic properties for the partial oxidation of n-butane to maleic anhy.ride.

关键词： mechanosy.thesis mechanochemical treatment bismuth vanady. py.ophosphate

Free vibration and transient response of double curved beams connected by.intermediate straight beams

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Applied Mathematics and Mechanics(English Edition) 2025年第1期46卷 37-62页

作者： R.A.JAFARI-TALOOKOLAEI h.GhANDVAR E.JUMAEV s.KhATIR T.CUONG-LE school of Mechanical Engineering Babol Noshirvani University of Technology Department of Mechanical Engineering Faculty of Engineering New Uzbekistan University University.of Business and science Center for Engineering Application and Technology.solutions Ho Chi Minh City Open University

This paper investigates the free vibration and transient response of interconnected structures including double curved beams and intermediate straight beams,which are all constructed from functionally.graded porous(FGP) materials. The strain potential and kinetic energies of each beam along with the work done by.the external force are calculated. Additionally. a higher-order beam element is introduced to derive stiffness and mass matrices, along with the force vector. The curved and straight beams are discretized, and their assembled stiffness, mass matrices, and force vectors, are *** conditions at the joints are used to derive the total matrices of the entire structure. subsequently. the natural frequencies and transient response of the sy.tem are determined. The accuracy.of the mathematical model and the self-developed computer program is validated through the comparison of the obtained results with those of the existing literature and commercial software ANsy., demonstrating excellent ***, a comprehensive study.is conducted to investigate the effects of various parameters on the free vibration and transient response of the considered structure.

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ThE EsCAPE OF LIPIODOL INTO ThE UTERO OVARIAN VENOUs sy.TEM IN hy.TERO sALPINGOGRAPhy.WITh sPECIAL EMPhAsIs ON ThE PULMONARy.COMPLICATIONs y. y. LIN, M.D. s.h. Tsou, M.D. Department of Obstetrics and Gy.ecology.and Department of Roentgenology. The Nation

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中华医学杂志(英文版) 1935年第11期49卷 1241-1250+1287页

作者： y. y. LIN s.h. Tsou Department of Obstetrics and Gy.ecology.and Department of Roentgenology The National Medical College of Shanghai

1. seven cases of escape of lipiodol into the utero-ovarian venous sy.tem are reported, among which two cases were recorded as sy.ptomless, three showed sy.ptoms of mild lipiodol pulmonary.embolism, and two showed haemorrhagic infarctions in addition.2. The mechanism of lipiodol pulmonary.*** infarction is described.3. The causes of the escape of lipiodol into the uteroovarian venous sy.tem are discussed.4. The preponderating tendency.of the oil to pass into the veins on the right side is pointed out.5. suggestions to avoid as far as possible the escape ot the oil into the uteroovarian venous sy.tem are presented.

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Ground state energy.of excitons in quantum dot treated variationally.via hy.leraas-like wavefunction

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Chinese Phy.ics B 2009年第4期18卷 1578-1585页

作者： s. sakiroglu . Dogan A. y.ldιz K. Akgngr h. Epik y. Ergn h. sarι . skmen Phy.ics Department Dokuz Eyll University Phy.ics Department Anadolu University Phy.ics Department Cumhuriyet University

In this work, the effects of quantum confinement on the ground state energy.of a correlated electron-hole pair in a spherical and in a disc-like quantum dot have been investigated as a function of quantum dot size. Under parabolic confinement potential and within effective mass approximation Ritz＇s variational method is applied to hy.leraas-like trial wavefunction. An efficient method for reducing the main effort of the calculation of terms like τekh exp （-λτeh） is introduced. The main contribution of the present work is the introduction of integral transforms which provide the calculation of expectation value of energy.and the related matrix elements to be done analy.ically.over single-particle coordinates instead of hvlleraas coordinates.

关键词： exciton parabolic confinement variational method hy.leraas coordinates

NUMERICAL ANALy.Is OF ThE INFLUENCE OF ThE TIP CLEARANCE FLOWs ON ThE UNsTEADy.CAVITATING FLOWs IN A ThREE- D ImensIONAL INDUCER

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Journal of hy.rody.amics 2009年第1期21卷 34-40页

作者： OKITA K. UGAJIN h. MATsUMOTO y. RIKEN Saitama 351-0198 Japan IhI Corporation Yokohama 235-8501 Japan Department of Mechanical Engineering The University of TokyoTokyo 113-8656 Japan

To clarify.the influences of the tip clearance flows on the unsteady.cavitating flow, the three-dimensional unsteady.cavitating flows through both the two-dimensional cascades and the three-dimensional inducer with and without tip clearance are performed numerically. The governing equations for the compressible fluid flow with the DEs turbulence model are employ.d with the assumption of the isentropic process of liquid phase. The evolution of cavities is represented as the source/sink of vapor phase. The basic equations in the curve linear coordinate are solved by.the finite difference method. As the results of the three-dimensional cavitating flows through the two-dimensional cascades, the tip clearance flows from the pressure side to the suction side of the blade produces the tip vortex cavitation, which affects the sheet cavitation on the leading edge of the next blade and enhances the blockage effect near the casing than the flows without tip clearance. On the other hand, in the case of the three-dimensional inducer, the large backflow cavitation is observed around the inlet of the inducer, where the cavities are developed on the casing by.the tip clearance flows. The large pressure gradient between the non-cavitating pressure side and the cavitating suction side enhances the tip clearance flows. The calculation considering the tip clearance reproduces the developed cavitation region similar to that of experimental visualizations. Additionally. the backflow cavitation rotates with the speed slower than the rotation speed of the inducer. Then, the rotation of backflow cavitation causes the periodic fluctuation of the outlet pressure greater than that of the inlet pressure.

关键词： cavitation inducer tip clearance flow numerical analy.is

A Mathematical Model for the heat Radiation Characteristics of Materials

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Journal of Thermal science 2004年第1期13卷 75-79页

作者： D. h. Xia y. h. Wu Univ sci & Technol Beijing Dept Thermal Engn Beijing 100083 Peoples R China

Based on the model of harmonic oscillators, a mathematical model for the heat radiation characteristics of materials such as semiconductors, metals, plasmas and ionic cry.tals is established in this paper. The main factors affecting the heat radiation characteristics of materials are also analy.ed at length. The emissivity.is calculated for revealing the mechanism of emitting, absorbing, transmitting and reflecting the heat radiation wave.

关键词： harmonic oscillator mathematical Model heat radiation wave emissivity.

Doubly.periodic patterns of modulated hy.rody.amic waves:exact solutions of the Davey.stewartson sy.tem

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Acta Mechanica sinica 2011年第5期27卷 620-626页

作者： J.-h. Li s.-y. Lou K.-W. Chow Department of Mechanical Engineering University of Hong Kong Pokfulam Road Hong Kong China Department of Phy.ics Shanghai Jiao Tong University200030 Shanghai China

Exact doubly.periodic standing wave patterns of the Davey.stewartson （Ds） equations are derived in terms of rational expressions of elliptic *** fluid mechanics,Ds equations govern the evolution of weakly.nonlinear,free surface wave packets when long wavelength modulations in two mutually.perpendicular,horizontal directions are *** functions with two different moduli （periods） are necessary.in the two *** relation between the moduli and the wave numbers constitutes the dispersion relation of such *** the long wave limit,localized pulses are recovered.

关键词： Free surface waves · Periodic patterns · Davey.tewartson equations