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81.
Nuri Oncel 《Surface science》2006,600(20):4690-4693
The diffusion and binding of CO molecules on self organized Pt nanowires on Ge(0 0 1), have been studied by room temperature scanning tunneling microscopy. CO molecules are found to bind at the bridge position of the Pt dimers. The CO molecules are mobile at room temperature and perform an “unrestricted” one-dimensional random walk in defect-free regions of the Pt nanowires. 相似文献
82.
83.
Salim Yüce 《数学物理学报(B辑英文版)》2011,31(1):172-180
In this article, we give the area formula of the closed projection curve of a closed space curve in Lorentzian 3-space L3. For the 1-parameter closed Lorentzian space motion in L3, we obtain a Holditch Theorem taking into account the Lorentzian matrix multiplication for the closed space curves by using their othogonal projections onto the Euclidean plane in the fixed Lorentzian space. Moreover, we generalize this Holditch Theorem for noncollinear three fixed points of the moving Lorentzian space and any other fixed point on the plane which is determined by these three fixed points. 相似文献
84.
We have investigated the structure and energies of lithium microclusters containing 3-10 atoms in the fcc(100) and fcc(110) surface symmetries, and the interaction of an oxygen and hydrogen atom with these lithium microclusters for the on-top, open and bridge sites approaches. The calculations have been performed with molecular dynamics simulation methods (MDSM) at 1 K temperature and the results were compared with the literature. 相似文献
85.
The effects of non-linear fluid-structure interaction on the dynamic buckling of structures are investigated. In particular the structural buckling characteristics are studied for the case of a strong shock wave propagating through a fluid medium striking a structure. Non-linear terms are retained for both fluid and structural systems. A one-dimensional example consisting of a perfect gas-spring-mass system is solved for shock wave loading. Solutions are obtained by using the finite element method. The numerical methods utilized appear to be applicable to complex multi-dimensional systems. It is shown that in a non-linear fluid-structure interaction problem the incident pressure may be amplified significantly during reflection from a structure. Thus, an acoustic fluid model may be non-conservative for strong shock problems. Structures in a fluid will buckle at an incident pressure level which is much less than that which causes buckling in a vacuum. 相似文献
86.
Oncel N Hallback AS Zandvliet HJ Speets EA Ravoo BJ Reinhoudt DN Poelsema B 《The Journal of chemical physics》2005,123(4):044703
Single-electron tunneling through Au substrate-alkanethiol-Pd cluster-tip junctions is investigated with scanning tunneling spectroscopy. The measured I(V) curves reveal several characteristic features of the Coulomb blockade, namely, the presence of a Coulomb gap and a Coulomb staircase. By using the orthodox theory of single-electron tunneling, the capacitances and resistances of the double junction system as well as the fractional charge are extracted from the experimental data. 相似文献
87.
The transient response of a spherical shell in an acoustic medium is studied. The exact solution is obtained by expressing the classical spherical wave equation in terms of a residual potential. Approximate solutions are obtained from the use of eight functions; namely, doubly asymptotic approximations, δ-sequence functions, and spherical wave approximations. The advantages and disadvantages of these approximate solutions are pointed out. The third member of the class of the modal doubly asymptotic approximations for a spherical surface and an improved spherical wave approximation are introduced. 相似文献
88.
Oncel N van Houselt A Huijben J Hallbäck AS Gurlu O Zandvliet HJ Poelsema B 《Physical review letters》2005,95(11):116801
The existence of one-dimensional (1D) electronic states between self-organized Pt nanowires spaced 1.6 or 2.4 nm apart on a Ge(001) surface is revealed by low-temperature scanning tunneling microscopy. These perfectly straight Pt nanowires act as barriers for a surface state (located just below the Fermi level) of the underlying terrace. The energy positions of the 1D electronic states are in good agreement with the energy levels of a quantum particle in a well. Spatial maps of the differential conductivity of the 1D electronic states conclusively reveal that these states are exclusively present in the troughs between the Pt nanowires. 相似文献
89.
The title compound, bis[2-[N-(2-chlorophenyl)formimidayl]-1-naphtholato]-(6Cl) copper(II), [Cu(C17H11NOCl)2] (1) was synthesized and its crystal structure was determined. The Compound 1 is monoclinic, space group P2 1/c with a = 9.146(3) Å, b = 18.724(3) Å, c = 16.230(2) Å, β = 96.46(1)°, V = 2761.8(11) Å3, Z = 4, D c = 1.503 g cm?3, μ(Mo Kα) = 1.020 mm?1, R = 0.0606 for 2361 reflections [I > 2σ(I)]. In the title compound, the Cu atom is coordinated by an N2O2 donor set from the imine-phenol ligand in a slightly distorted square planar coordination geometry, with the two phenolate O atoms being deprotonated. The Cu–O bond lengths are 1.878(4) and 1.889(4) Å, the Cu–N bond lengths are 1.980(5) and 1.985(5) Å. The angles O1–Cu–N1 and O2–Cu–N2 are 90.96(19) and 90.72(19)°, respectively. 相似文献
90.
Leila O. Khafizova Nuri M. Chobanov Mariya G. Shaibakova Natalya R. Popodko Tatyana V. Tyumkina Usein M. Dzhemilev 《Tetrahedron》2018,74(20):2482-2487
An original method for the synthesis of С5-С6 cyclic ketones and tetrasubstituted furans was developed based on the Cp2TiCl2-catalyzed reaction of symmetrical alkynes and α,ω-dicarboxylates in the presence of Mg and ЕtAlCl2. The length of the hydrocarbon chain between carboxyl groups in a,ω-dicarboxylic acid esters affects the chemoselectivity of the reaction. The formation of 2-alkylidene and 2-alkenyl cyclopent(hex)an-1-ones occurred in the reaction with esters of glutaric and adipic acids. α,ω-Dicarboxylic acid esters with more than four methylene units between carboxyl groups gave rise to substituted furans. Stereochemistry of 2-alkenyl cyclopent(hex)an-1-ones was determined based on the analysis of experimental and theoretical data obtained from DFT calculations. 相似文献