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An augmented Lagrange algorithm for nonlinear optimizations with second-order cone constraints is proposed based on a Löwner operator associated with a potential function for the optimization problems with inequality constraints. The favorable properties of both the Löwner operator and the corresponding augmented Lagrangian are discussed. And under some mild assumptions, the rate of convergence of the augmented Lagrange algorithm is studied in detail. 相似文献
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以邻氨基二苯甲酮为原料,经两分子环化缩合反应制得6,12-二芳基二苯并[b,f][1,5]二氮杂环辛四烯(2a~2d);2a~2d经LiAlH4还原制得6,12-二芳基-5,6,11,12-四氢二苯并[b,f][1,5]二氮杂环辛(3a~3d);3a~3d与醛(或酮)反应,合成了一系列新型的多取代Tr(o)ger's base衍生物(4a~4d和5a~7a),其结构经1H NMR, 13C NMR, HR-MS(ESI)和X-射线单晶衍射表征.通过分析架桥前后3a(CCDC: 1498564)和6a(CCDC: 1498555)的晶体结构,解释了该类化合物1H NMR中NCH质子及桥上取代基质子裂分的原因,并进一步证实了4~7为非C2轴对称结构. 相似文献
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Gareth J. Rowlands Author Vitae 《Tetrahedron》2010,66(9):1593-501
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C. Liu Q. Gong Y. Chen H. Chen D. Qiang 《Applied Physics A: Materials Science & Processing》2001,73(4):477-479
A novel rhodamine-B cation fulleride salt was synthesized by metathetical reaction. Its tetrahydrofuran solution was prepared
and the fluence-dependent transmission was measured with 10-ns 532-nm laser pulses in a collimated optical setup. With increases
in the input fluence, its transmittance decreased significantly, which indicated reverse saturable absorption behavior. For
comparison, the input fluence-dependent transmittance of fullerene C60 and rhodamine-B solution were also measured. The nonlinear optical limiting effect of the fulleride salt in tetrahydrofuran
is slightly lower than that of C60 in toluene and the explanations are provided.
Received: 25 August 2000 / Accepted: 6 November 2000 / Published online: 3 April 2001 相似文献
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F. Leardini J.F. Fernández J. Bodega C. Sánchez 《Journal of Physics and Chemistry of Solids》2008,69(1):116-127
The kinetics of simultaneous hydrogen and deuterium thermal desorption from PdHxDy has been investigated. A novel experimental approach for the study of the transition state (TS) characteristics of the surface recombination reaction is proposed based on the analysis of the H and D partitioning into H2, HD and D2 molecules. It has been found that the hydrogen molecular isotopes distribution is determined by the energy differences of the corresponding TS of the atom-atom recombination reactions. On the other hand, the mechanisms and activation energies of the desorption process have been obtained. At 420 K, the desorption reaction changes from a surface recombination limiting mechanism during desorption from β-PdHxDy to a reaction limited by the rate of β to α phase transformation during the two phase coexistence. Surface recombination reaction becomes again rate limiting above 480 K, due to a change in the catalytic properties of the Pd surface. TS energies obtained from the kinetic analysis of the thermal desorption spectra are in good accordance with those obtained from the analysis of the H2, HD and D2 distributions. Anomalous TS energies have been observed for the H-D recombination reaction, which may be related to the heteronuclear character of this molecule. 相似文献
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Chemical Structure of HfO2/Si Interface with Angle-Resolved Synchrotron Radiation Photoemission Spectroscopy 下载免费PDF全文
Interracial chemical structure of HfO2/Si (100) is investigated using angle-resolved synchrotron radiation photoemission spectroscopy (ARPES). The chemical states of Hf show that the Hf 4f binding energy changes with the probing depth and confirms the existence of Hf-Si-O and Hf Si bonds. The Si 2p spectra are taken to make sure that the interracial structure includes the Hf silicates, Hf silicides and SiOx. The metallic characteristic of the Hf-Si bonds is confirmed by the valence band spectra. The depth distribution model of this interface is established. 相似文献
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Th. Cabioc'h S. Camelio L. Henrard Ph. Lambin 《The European Physical Journal B - Condensed Matter and Complex Systems》2000,18(3):535-540
Concentric-shell fullerenes, also called carbon onions, produced by carbon ion implantation into silver thin films, and subsequently
deposited on a silica substrate, were studied by optical transmission spectroscopy in the wavelength range 0.2 - 1.2 μm. In
this interval, the strongest absorption is due to the π-plasmon of sp2-like carbon. The position of the plasmon absorption band clearly evolved from 265 nm at low fluence to 230 nm at high implantation
fluences. A simulation of the optical spectra based on dielectric models of the concentric-shell fullerenes layer allowed
us to identify the first peak as due to disordered graphite and the latter to the carbon onions. The concentration of residual
graphite and the filling fraction of the carbon onions produced at high fluences could be estimated by fitting the optical
spectra with computed transmittance curves.
Received 13 July 2000 相似文献
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We employ the particle-in-cell method to simulate the mechanisms of femtosecond (fs) laser interactions with a metallic target. The theoretical approach considers the solid as a gas of free electrons in a lattice of immobile ions and the laser fluences close to the ablation threshold. At first moments of the interaction, our simulations mapped out different nanostructures. We carefully characterized the rippling phase and found that its morphology is dependent on the distribution of the electron density and the period of the ripples depends on the laser intensity. The simulation method provides new insights into the mechanisms that are responsible for surface grating formation. 相似文献