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201.
Dielectric permittivity studies on the nematic liquid crystal p-(ethoxy phenyl azophenyl) butyrate were carried out at 1 MHz. The effect of parallel and perpendicular magnetic fields on the alignment of the molecules was studied. The threshold voltage for domain formation in the presence of a magnetic field is estimated. 相似文献
202.
203.
Motivated by recent experiments on suspended graphene showing carrier mobilities as high as 200,000 cm2/V s, we theoretically calculate transport properties assuming Coulomb impurities as the dominant scattering mechanism. We argue that the substrate-free experiments done in the diffusive regime are consistent with our theory and verify many of our earlier predictions including (i) removal of the substrate will increase mobility since most of the charged impurities are in the substrate, (ii) the minimum conductivity is not universal, but depends on impurity concentration with cleaner samples having a higher minimum conductivity. We further argue that experiments on suspended graphene put strong constraints on the two parameters involved in our theory, namely, the charged impurity concentration and d, the typical distance of a charged impurity from the graphene sheet. The recent experiments on suspended graphene indicate a residual impurity density of which are presumably stuck to the graphene interface, compared to impurity densities of for graphene on SiO2 substrate. Transport experiments can therefore be used as a spectroscopic tool to identify the properties of the remaining impurities in suspended graphene. 相似文献
204.
This letter presents the experimental characterization of tapered and stripe superluminescent diodes fabricated from 980-nm high-power triple quantum-well InGaAs-AlGaAs semiconductor material. Record output powers in excess of 1.3 W pulsed have been measured, with 0.1-dB spectral modulation and maximum wall-plug efficiency 16%. Almost 1-W optical power into multimode optical fibers has been achieved with preliminary measurements of coupling efficiency. 相似文献
205.
V. Padmavathi M. Rajagopala Sarma K. Venugopal Reddy A. Padmaja D. Bhaskar Reddy 《Heteroatom Chemistry》2003,14(2):155-159
The cycloaddition of diazomethane, cyclocondensation of hydrazine hydrate, and cyclopropanation of TMSOI to 1‐aroyl‐2‐styrylsulfonylethenes were studied and different novel products thereby obtained were characterized with spectral parameters. © 2003 Wiley Periodicals, Inc. Heteroatom Chem 14:155–159, 2003; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/hc.10117 相似文献
206.
N. Krishna Murthy S. L. Narasimha Rao D. R. R. Sarma 《Fresenius' Journal of Analytical Chemistry》1995,351(6):586-587
Iron (II)-cacotheline-oxalate blue solution is used as reductometric reagent for the estimation of dissolved oxygen. By titrating the blue complex solution photometrically, the dissolved oxygen in water samples can be accurately determined in the range of 2 to 8 mg/l. The stoichiometry of the reaction between dissolved oxygen and the blue complex was found to be 1:0.8 or 5:4. The applicability of this method to distilled water, river water and reservoir water was tested.The Winkler's method [1] and its various modifications and adaptations, widely used for the determination of dissolved oxygen, are laborious and time consuming. Therefore a new method using iron (II)-cacotheline-oxalate (ICO) blue solution was developed for this purpose. 相似文献
207.
In this paper we review our recent study of coherent electronic properties of coupled two-dimensional quantum dot arrays using numerical exact-diagonalization methods on a Mott–Hubbard type correlated tight-binding model. We predict the existence of a novel kind of persistent current in a two-dimensionalisolatedarray of quantum dots in a transverse magnetic field. We calculate the conductance spectrum for resonant tunneling transport through a coherent two-dimensional array of quantum dots in the Coulomb Blockade regime. We also calculate the effective two-terminal capacitance of an array coupled to bias leads. 相似文献
208.
Multipliers on Vector-valued <Emphasis Type="Italic">L</Emphasis><Superscript>1</Superscript>-spaces for Hypergroups 下载免费PDF全文
In this article, we extend the well known Wendel’s theorem to the context of vector-valued L1-spaces on hypergroups. In this regard, various cases have been studied. 相似文献
209.
Amarendra K. Sarma Manirupa Saha Anjan Biswas 《Journal of Infrared, Millimeter and Terahertz Waves》2010,31(9):1048-1056
This paper studies the optical solitons with power law nonlinearity in presence of Hamiltonian perturbation terms. The perturbation
terms that are taken into account are inter-modal dispersion, third order dispersion, self-steepening term and nonlinear dispersion.
An exact 1-soliton solution is obtained by the solitary wave ansatz. Both bright and dark optical soliton solutions are obtained.
The domain restrictions have also been identified in the process. 相似文献
210.
A novel vanadium polyoxometalate [(C6H5CH2)(CH3)3N]3[H3V10O28]3H2O works as a useful oxidant for selective and rapid oxidation of benzylic alcohols to the corresponding carbonyl compounds in the presence of PTSA under solvent-free, room temperature in excellent yield. 相似文献