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111.
Abstract The near ultra-violet absorption spectrum of parafluoro phenetole has been studied in vapour phase. About 135 red degraded Bands have been measured. These have been explained in terms of five ground state (187, 258, 346, 633 and 855 cm1) and seven excited state (151, 306, 527, 816, 966, 1279 and 1328 cm?1) fundamental frequencies. A red shift of 1243 cm?1 of (0,0) hand relative to that of Phenetole is also observed. 相似文献
112.
Optical properties of orange phased HgGa2S4 crystal is investigated. Generation of tunable middle infrared radiation by second harmonic of tunable CO2 laser radiation has been demonstrated. Second harmonic conversion efficiency with respect to other infrared crystal has also been discussed. 相似文献
113.
The thermodynamics of general relativistic systems with boundary, obeying a Hamiltonian constraint in the bulk, is determined
solely by the boundary quantum dynamics, and hence by the area spectrum. Assuming, for large area of the boundary, (a) an
area spectrum as determined by non-perturbative canonical quantum general relativity (NCQGR), (b) an energy spectrum that
bears a power law relation to the area spectrum, (c) an area law for the leading order microcanonical entropy, leading thermal
fluctuation corrections to the canonical entropy are shown to be logarithmic in area with a universal coefficient. Since the
microcanonical entropy also has universal logarithmic corrections to the area law (from quantum space-time fluctuations, as
found earlier) the canonical entropy then has a universal form including logarithmic corrections to the area law. This form
is shown to be independent of the index appearing in assumption (b). The index, however, is crucial in ascertaining the domain
of validity of our approach based on thermal equilibrium. 相似文献
114.
The use of Amberlite-LA-2, a high molecular weight secondary amine, for the radiochemical solvent extraction of Ag(I) present as anionic thiosulfato complex at pH 3 is described. The effects of different parameters on the extraction and preconcentration have been studied in detail. The method was successfully applied in the determination of silver in several synthetic mixutres and also in a few medicinal samples. 相似文献
115.
We demonstrate the method of averaging for conservative oscillators which may be strongly nonlinear, under small perturbations including delayed and/or fractional derivative terms. The unperturbed systems studied here include a harmonic oscillator, a strongly nonlinear oscillator with a cubic nonlinearity, as well as one with a nonanalytic nonlinearity. For the latter two cases, we use an approximate realization of the asymptotic method of averaging, based on harmonic balance. The averaged dynamics closely match the full numerical solutions in all cases, verifying the validity of the averaging procedure as well as the harmonic balance approximations therein. Moreover, interesting dynamics is uncovered in the strongly nonlinear case with small delayed terms, where arbitrarily many stable and unstable limit cycles can coexist, and infinitely many simultaneous saddle-node bifurcations can occur. 相似文献
116.
Solution‐Based Synthesis of Layered Intergrowth Compounds of the Homologous PbmBi2nTe3n+m Series as Nanosheets
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Arindom Chatterjee Dr. Kanishka Biswas 《Angewandte Chemie (International ed. in English)》2015,54(19):5623-5627
Layered intergrowth compounds in the homologous PbmBi2nTe3n+m family are interesting because they are examples of natural heterostructures. We present a simple solution‐based synthesis of two‐dimensional nanosheets of PbBi2Te4, Pb2Bi2Te5, and PbBi6Te10 layered intergrowth compounds, which are members of the PbmBi2nTe3n+m [that is, (PbTe)m(Bi2Te3)n] homologous series. Few‐layer nanosheets exhibit narrow optical band gaps (0.25–0.7 eV) with semiconducting electronic‐transport properties. 相似文献
117.
Om Prakash Shiv Kumar Pushkar Singh Volker Deckert S. Chatterjee A.K. Ghosh Ranjan K. Singh 《Journal of Raman spectroscopy : JRS》2016,47(7):813-818
Interest in the synthesis of hybrid substrates for surface‐enhanced Raman scattering (SERS) has surged recently. Hereof, in the present work, a hybrid SERS substrate CuO : Mn/Ag heterojunction has been synthesised. To accomplish this, the nanostructred Ag island film and CuO : Mn nanoparticles are synthesised by vacuum thermal evaporation method and sol–gel method respectively, and thereafter, a heterojunction between the CuO : Mn and Ag is fabricated by adsorption of CuO : Mn (10‐3 m in ethanol) on Ag island film. Further, the SERS sensitivity of CuO : Mn/Ag heterojunctions has been studied by probing methyl orange. We observed that with Mn‐doping in the lattice of CuO, the SERS signal is enhanced considerably because of ferromagnetic ordering in CuO : Mn. DFT/B3LYP/6‐311 G(d, p) method is used to calculate the energy of HOMO and LUMO level of methyl orange. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献
118.
Tamoghna Bhattacharyya Arumoy Chatterjee Budhaditya Chatterjee Sufi O. Raja Anjan Kr. Dasgupta 《Electrophoresis》2015,36(24):3009-3013
We report both the experimental and theoretical insights of differential electro‐diffusion behavior of carbon nanomaterials (e.g. single wall, multiwall carbon nanotubes, and graphene). We thus discriminate one from the other in a soft gel system. The differential mobility of such material depends on their intrinsic properties, both extend and rate of migration bearing the discriminatory signature. The mobility analysis is made by a real time monitoring of the respective bands. 相似文献
119.
Debabrata Chatterjee Namita Jaiswal Jagadeesh C. Bose K Ram Balak Mahato Diptendu Bhattacharyya 《Journal of Coordination Chemistry》2015,68(17-18):3229-3235
Reaction of [RuIII(EDTA)(CyS)]2? (edta4? = ethylenediaminetetraacetate; CySH = cysteine) with molecular oxygen (O2) has been studied as a function of pH (4.0–8.0) and cysteine concentration (0.2–2.0 mM) at room temperature (25 °C). Biological activities of the [Ru(EDTA)]/CySH/O2 system pertaining to cleavage of supercoiled plasmid DNA to its nicked open circular form has been explored in this work. Results are discussed in regard to the reaction of the ruthenium(III)-complex with molecular oxygen) and a working mechanism is proposed for the biological activities of the ruthenium(III)-complex in the presence of O2. 相似文献
120.
Primary objective of this study was to develop a stability-indicating reverse-phase high-performance liquid chromatography (HPLC) method for simultaneous quantitation of tramadol and aceclofenac in presence of their degradation products. The drugs were subjected to various International Conference on Harmonization recommended stress conditions, such as acid hydrolysis, alkaline hydrolysis, peroxide oxidation, thermolysis, and photolysis. The major degradation products got well resoluted from the analytes in HPLC analysis with a mobile phase composed of a mixture of 0.01?M ammonium acetate buffer (pH 6.5) and acetonitrile (65:35, v/v) through a Phenomenex Gemini C18 (250?mm?×?4.6?mm, 5?µm particle size) column. The method was linear over a range of 15–60?µg/mL for tramadol and 40–160?µg/mL for aceclofenac concentration. The analytes were detected at a wavelength of 270?nm. The method was validated and found to be specific, accurate, precise, stable, and robust for its intended use. The method can be recommended for its future use in routine quality control, accelerated and real-time stability analysis of the formulations containing tramadol and aceclofenac combination. 相似文献