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91.
A. G. Milekhin N. A. Yeryukov L. L. Sveshnikova T. A. Duda E. I. Zenkevich S. S. Kosolobov A. V. Latyshev C. Himcinski N. V. Surovtsev S. V. Adichtchev Zhe Chuan Feng Chia Cheng Wu Dong Sing Wuu D. R. T. Zahn 《Journal of Experimental and Theoretical Physics》2011,113(6):983-991
Raman scattering (including nonresonant, resonant, and surface enhanced scattering) of light by optical and surface phonons of ZnO nanocrystals and nanorods has been investigated. It has been found that the nonresonant and resonant Raman scattering spectra of the nanostructures exhibit typical vibrational modes, E 2(high) and A 1(LO), respectively, which are allowed by the selection rules. The deposition of silver nanoclusters on the surface of nanostructures leads either to an abrupt increase in the intensity (by a factor of 103) of Raman scattering of light by surface optical phonons or to the appearance of new surface modes, which indicates the observation of the phenomenon of surface enhanced Raman light scattering. It has been demonstrated that the frequencies of surface optical phonon modes of the studied nanostructures are in good agreement with the theoretical values obtained from calculations performed within the effective dielectric function model. 相似文献
92.
Sing M Glawion S Schlachter M Scholz MR Goss K Heidler J Berner G Claessen R 《Physical review letters》2011,106(5):056403
The spectral weight evolution of the low-dimensional Mott insulator TiOCl upon alkali-metal dosing has been studied by photoelectron spectroscopy. We observe a spectral weight transfer between the lower Hubbard band and an additional peak upon electron doping, in line with quantitative expectations in the atomic limit for changing the number of singly and doubly occupied sites. This observation is an unconditional hallmark of correlated bands and has not been reported before. In contrast, the absence of a metallic quasiparticle peak can be traced back to a simple one-particle effect. 相似文献
93.
Self-associating polymers are ubiquitous in synthetic and biological systems. Here, we use a combination of simulation and theory to show that these polymers exhibit a counterintuitive strong nonmonotonic stretching response in shear flow. Furthermore, we demonstrate that this behavior can be tuned by controlling the barrier for dissociation of the bonds and develop a quantitative and predictive theory based on conformational transitions to explain the observed behavior. Our results can be important in understanding previous experimental and theoretical observations and further aid in the development of novel smart materials. 相似文献
94.
We demonstrate a high-sensitivity broadband (1250-1650 nm) fiber micro-Michelson interferometer using a single-mode fiber end-spliced with a sphered-end hollow-core fiber. The hollow core is slightly smaller than the solid core of a single-mode fiber, so the fractional power of the core mode is converted into cladding modes. The excited cladding modes propagate at distinct optical paths along the hollow-core fiber and have individual foci outside the spherical lens. The reflected core mode, generated at the solid core-air interface, and the reflected cladding modes, generated at external material, interfere with each other to produce beating in the interference signals. 相似文献
95.
Long Min Yang Zhang Xuefeng Liang Junrong Huang Wenli Bao Dr. Chi‐Sing Lee 《Angewandte Chemie (International ed. in English)》2014,53(42):11294-11297
A highly diastereoselective and practical biomimetic total synthesis of (±)‐basiliolide B has been achieved through the study of the two proposed biosynthetic pathways (O‐methylation and O‐acylation) for the unprecedented 7‐methoxy‐4,5‐dihydro‐3H‐oxepin‐2‐one (C ring). The synthesis featured a cyclopropanation/ring opening strategy for establishing the stereogenic centers at C8 and C9, a biomimetic 2‐pyrone Diels–Alder cycloaddition for the synthesis of the ABD ring system, and finally a highly efficient biomimetic intramolecular O‐acylation for the C ring formation. This result provides an important perspective on the biosynthetic origin of the unprecedented 7‐membered acyl ketene acetal moiety of the C ring. 相似文献
96.
The structure of PhHg(S2CNPr2) shows a distorted linear geometry about mercury defined by a sulfur and a carbon atom. Centrosymmetric molecules aggregate via Hg?S interactions to form loosely associated dimers. Copyright © 2003 John Wiley & Sons, Ltd. 相似文献
97.
The structure of As(S2CNMe2)3 has approximate threefold symmetry and features essentially monodentate dithiocarbamate ligands, so that the geometry is trigonal pyramidal. Copyright © 2003 John Wiley & Sons, Ltd. 相似文献
98.
Generic bifurcations of varieties 总被引:2,自引:0,他引:2
Shyūichi Izumiya 《manuscripta mathematica》1984,46(1-3):137-164
We study the zero point set of a parametrized smooth map germ. It is not only a natural generalization of Mather's theory of smooth map germs (cf. [11],[12]), but also it contains the bifurcation theory of stationary solutions of parametrized ordinary differential equations. One of our main results is a classification of parametrized smooth map germs under a certain equivalence relation.Dedicated to Professor Minoru Nakaoka on his 60th birthday 相似文献
99.
Two waveguide CO2 lasers, a quartz waveguide and an alumina waveguide, have been studied on the 00°2–[10°l,02°1]I,II sequence bands. The use of an intra-cavity hot CO2 cell, which is a part of the waveguide, suppresses the regular-band transitions. The quartz waveguide laser has a total of 58 lines lasing on both the 9.4 µm and 10.4 µ,m sequence bands. The alumina waveguide laser has 36 lines lasing on the 10.4 µm sequence band and twice the output power of the quartz waveguide laser, whereas lasing on the 9.4 µm sequence band is difficult. The lasers can be operated on the selected single line without line jumping problem. The frequency tuning range of the strong lines is limited by the free spectral range of the cavity. 相似文献
100.
The mononuclear structure of Zn(S2CN(CH2)4)2(4,7‐Ph2‐1,10‐phenanthroline) shows the zinc atom in each of the two independent molecules comprising the asymmetric unit to exist in a distorted octahedral geometry defined by an N2S4 donor set. Copyright © 2003 John Wiley & Sons, Ltd. 相似文献