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961.
962.
This paper describes the dynamics of a water-in-oil microemulsion from the dilute to the dense droplet region. Using the relative intermediate form factor method for neutron spin echo data analyses [M. Nagao, H. Seto, Phys. Rev. E 78 (2008) 011507], the shape and structure fluctuations of a droplet microemulsion are successfully decoupled. In the previous paper, we used the first cumulant analysis of the shape fluctuation model, while the full fitting form of the same model is applied in this paper. The final results of the fittings using the first cumulant approximation and the full form of the model are almost identical, and therefore, the validity of the method is strengthened. The estimated bending modulus of the surfactant membrane, κ, is basically the same, within the experimental errors, in the previous and present results. The κ is not affected much by an increase of the droplet concentration. A clear dynamic slowing down of the water droplets is highlighted at the length scale corresponding to the inter-droplet distance from the structure fluctuation analysis. 相似文献
963.
The quantized states in a quantum-well semiconductor laser are simulated analytically by a magnetic field perpendicular to the well (infinite quasi-one-dimensional potential well) by deriving a close relationship for the magnetic-field strength which becomes a discrete quantity. 相似文献
964.
A new kind of four-mode continuous variable coherent-entangled state is proposed in the Fock space by using the technique of integration within an ordered product,which exhibits both the properties of a coherent state and an entangled state,and spans a complete and orthonormal representation.The conjugate state of the four-mode continuous variable coherent-entangled state is derived by using the Fourier transformation.Moreover,a simple experimental protocol of generating a four-mode continuous variable coherent-entangled state is proposed by using beam splitters.As applications of this four-mode continuous variable coherent-entangled state,a four-mode entangled state and a four-mode squeezing-Fresnel operator are constructed. 相似文献
965.
研究了脉冲HF激光与水柱表面相互作用下电信号的产生过程。电信号显示了与激光能量线性相关的峰值间有时间间隔的两峰结构,且第二个尖峰在水柱底部的蒸汽腔塌缩后出现。实验还显示电信号的幅值和激光脉冲照射过程中是否存在膨胀和挤压的薄水层密切相关。如果在电池上边缘和石英平板(石英板紧邻电池,并与水柱上表面相接)之间存在一薄水层,电信号强度会增加10倍。 相似文献
966.
Y. Davila A. PetitmanginC. Hebert J. PerrièreW. Seiler 《Applied Surface Science》2011,257(12):5354-5357
The incorporation of oxygen atoms in oxide films grown by pulsed laser deposition depends upon the oxygen pressure and laser power density. By carefully controlling these two parameters it is possible to control the oxygen deficiency in the samples, and thus to change their physical properties from insulating and transparent to absorbing and conducting. By using X-ray diffraction, Rutherford backscattering spectroscopy and resistivity measurements, we show that depending upon the oxide materials oxygen deficiency in the films can induce either the growth of stable sub-oxide phases or the formation of nanocomposite films by phase separation. The first case corresponds to oxides with a mixed valency cation like Ti, which leads to the formation of stable, crystalline and highly conductive TiOx sub-oxide phases. The second case is well described by the indium tin oxides (ITO) in which a large oxygen deficiency leads to metallic clusters embedded into a stoichiometric matrix, i.e. nanocomposite films. This phenomenon is due to the fact that sub-oxides of these compounds are not stable and thus the oxygen deficiency induced a phase separation. 相似文献
967.
Shyjumon Ibrahimkutty Daniel Issenmann Stefan Schleef Anke‐Susanne Müller Yves‐Laurent Mathis Biliana Gasharova Erhart Huttel Ralph Steininger Jörg Göttlicher Tilo Baumbach Albrecht Bartels Christof Janke Anton Plech 《Journal of synchrotron radiation》2011,18(4):539-545
A high‐repetition‐rate pump–probe experiment is presented, based on the asynchronous sampling approach. The low‐α mode at the synchrotron ANKA can be used for a time resolution down to the picosecond limit for the time‐domain sampling of the coherent THz emission as well as for hard X‐ray pump–probe experiments, which probe structural dynamics in the condensed phase. It is shown that a synchronization of better than 1 ps is achieved, and examples of phonon dynamics of semiconductors are presented. 相似文献
968.
Ye Wu Irene Ling Li Ling Fu Jian pang Zhai Shuang Chen Ruan 《Applied Surface Science》2009,255(23):9409-9412
Excimer laser emitting at 248 nm is applied to produce microstructures on the surface of aluminum alloy. The surface morphology shows that hotspots and thermal fluidic structures both come to light. Two possible mechanisms of hotspots formation are proposed: near-field diffraction and interference, and extremely fast rapid thermal annealing. And for the formation of thermal fluidic pattern structure, a thin film model is applied. 相似文献
969.
970.
Atsushi Takamizawa Kayoko Mishina Kenzo Hiraoka 《Journal of mass spectrometry : JMS》2012,47(2):221-225
Covalent bonds are often created by a reaction between chemicals and protein before causing various adverse effects in a cell. Dimethylaminoethyl methacrylate (DMAEMA), which has moderate toxicity, causes skin inflammation and throat irritation. For this study, we investigated a reaction mechanism between myoglobin and (DMAEMA) using a new analytical tool developed at our laboratory: laser spray mass spectrometry technique. It was found that initially DMAEMA was added to the amino group of protein by the Michael addition mechanism; the added DMAEMA was hydrolyzed to methacrylic acid using an autocatalytic system. The results of this study indicate the feasibility of the laser spray technique in analyses of reaction dynamics. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献