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951.
This paper is concerned with the experimental studies on the sloshing response of liquid-filled containers. A three-dimensional
finite element analysis is carried out for the numerical simulation of this problem. The effects of sloshing are computed
in the time domain using Newmark's time integration scheme. A simple experimental setup is designed and fabricated in-house
to conduct experiments for measuring some of the basic parameters of sloshing. A sensor device is especially developed to
record the free-surface wave heights. Each wave height sensor is a capacitance probe that detects the change in level of liquid
(water) precisely with no time lag. The sensors are used in conjunction with a signal-processing unit in which the capacitance
values are transduced to a voltage signal between 0 V and 10 V. These wave height sensors simultaneously record the slosh
wave height near the periphery of the container wall from 16 predetermined locations to give the free-surface profiles of
liquid at desired time steps. The experimental results are compared with those obtained from the present theoretical analysis,
and good agreements are observed. 相似文献
952.
We have studied extensively phenomenological implications in a specific model of brane inflation driven by background supergravity (Choudhury and Pal, 2011) [1], via thermal history of the universe and leptogenesis pertaining to the particle physics phenomenology of the early universe. Using the one loop corrected inflationary potential we have investigated for the analytical expression as well as the numerical estimation for brane reheating temperature for standard model particles. This results in some novel features of reheating from this type of inflation which have serious implications in the production of heavy Majorana neutrinos needed for leptogenesis through the reheating temperature. We have also derived the expressions for the gravitino abundance during reheating and radiation dominated era. We have further estimated different parameters at the epoch of phase transition and revealed their salient features. At the end we have explicitly given an estimate of the amount of CP violation through the effective CP phase which is related to baryon asymmetry as well as gravitino dark matter abundance. 相似文献
953.
Bishnu P. Pal 《Fiber and Integrated Optics》2013,32(2):195-252
Abstract The current state of the art in optical communication fiber waveguide fabrication is reviewed. Details of the two main technologies—multi-component glasses and high-silica glasses—are described, followed by brief details of other fiber fabrication techniques. The relative advantages and disadvantages of the different fiber fabrication techniques are discussed in the summary. 相似文献
954.
R. G. Makitra G. G. Midyana E. Ya. Pal”chykova Ya. M. Vasyutyn 《Russian Journal of General Chemistry》2012,82(12):1975-1977
The experimentally measured rate constants of phthaloyl and terephthaloyl chlorides hydrolysis vary at the variable reagents ratio. This change obeys the Michaelis-Menten equation suggesting the intermediate formation by the reactants of the charge-transfer complex. 相似文献
955.
Plasma Chemistry and Plasma Processing - Plasmon thin film transistor has great potential to be applied in present-day technologies including modern medical diagnostics. Here, we report the... 相似文献
956.
R. G. Makitra G. G. Midyana E. Ya. Pal’chikova Ya. M. Vasyutyn 《Russian Journal of Organic Chemistry》2013,49(12):1731-1733
The rate constants of racemization of d-2,2′-dimethoxybiphenyl-6,6′-dicarboxylic acid in different solvents can be satisfactorily described by multiparameter equations based on the linear free energy relationship. The main factors responsible for solvent effects are their polarizability and electrophilic solvation power. 相似文献
957.
A. N. Zhukov N. S. Sidorov A. V. Pal’nichenko V. V. Avdonin D. V. Shakhray 《Journal of Experimental and Theoretical Physics》2010,110(2):275-279
The effect of steplike shock-wave compression up to 65 GPa on the crystal structure and super-conducting transition temperature
of a polycrystalline MgB2 sample is studied. X-ray diffraction demonstrates that the shock-wave compression of the MgB2 sample does not cause any irreversible structural phase transformations in it except for the formation of lattice microstrains.
These conclusions agree with the super-conducting transition temperatures of the MgB2 sample measured before and after shock-wave compression. 相似文献
958.
Absence of emission concentration quenching accompanied by high emission efficiency in a solid state is highly challenging though very attractive, for example, for fabrication of solid state light emitters or fluorescent organic nanoparticles (FONs). Here, formation of FONs based on novel p-phenylenediacetonitrile derivatives by re-precipitation method in aqueous solutions is demonstrated. The exceptionality of the derivatives employed is manifested by nitrile groups-induced steric hindrance effects inhibiting concentration quenching of emission. Consisting of different size and polarity end-groups, phenyl groups in one compound and hexyl-carbazolyl in another, the derivatives were examined and compared in regard to nanoparticle formation morphology, size tunability, spectral signatures, and fluorescence turn-on efficiency. The variation of solvent/non-solvent ratio allowed to achieve tuning of the FON sizes from 55?nm up to 360?nm and resulted in maximal fluorescence on/off ratio of 38. Spectrally resolved confocal fluorescence microscopy revealed somewhat different molecule arrangement in different FONs suggesting dominant amorphous-like phase, which was confirmed by small angle X-ray scattering measurements. The FONs were verified to be stable against degradation or conglomeration into larger clusters at least over a couple of months thus implying their feasibility for practical applications. Finally, potential application of the fluorescent p-phenylenediacetonitrile nanoparticles for organic vapor sensing via fluorescence on/off switching was demonstrated. 相似文献
959.
960.
Pinaki Sengupta Uttam Bhaumik Animesh Ghosh Amlan Kanti Sarkar Bappaditya Chatterjee Anirbandeep Bose Tapan Kumar Pal 《Chromatographia》2009,69(11-12):1243-1250
A simple, precise and reproducible liquid chromatography–tandem mass spectrometry method has been developed and validated according to the Food and Drug Administration guidelines for the simultaneous quantitation of antidiabetic drugs metformin, glimiperide and pioglitazone in human plasma using glipizide as an internal standard. Quantitation was performed on a triple quadrupole mass spectrometer employing electrospray ionization technique, operating in multiple reaction monitoring and positive ion mode. Inter-batch and intra-batch coefficient of variation across four validation runs for the quality control samples was less than 7%. The accuracy determined at quality control levels was within 92.81–105.13%. The method was applied to a bioequivalence study. 相似文献