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131.
132.
Anwar Ali Shadma Tasneem Priyanka Bidhuri Vidiksha Bhushan Nisar Ahmad Malik 《Russian Journal of Physical Chemistry A, Focus on Chemistry》2012,86(13):1923-1929
Conductivities, densities and ultrasonic speeds measurements of hexadecyltrimethylammonium bromide (HTAB) in aqueous solutions of glycine (Gly) and glycylglycine (Gly-Gly) have been made at various temperatures. The critical micelle concentration (CMC), the degree of ionization (??) of the micelles, standard free energy, enthalpy, and entropy of the micellization process (??G m ° , ??H m ° , and ??S m ° ) for the present systems were estimated at different temperatures. The CMC values of HTAB in aqueous Gly and Gly-Gly were also evaluated by density and ultrasonic speed measurements. Apparent molar volumes, (V ?), apparent molar volumes at infinite dilution, (V ? ° ), apparent molar compressibilities, (K ?), of HTAB in the pre- and post-micellar regions, and volume change on micellization (??V ? m ) were also estimated. Large positive values of T??S m ° and small negative values of ??H m ° suggest that micellization process is driven primarily by entropy increase. The increase in ??V ? m and K ? with rise in temperature is indicative of less compact micellar structure of HTAB in presence of amino acid additives. These data suggest that amino acids are solubilised probably in the palisade layer of the micelle. 相似文献
133.
Priyanka Srivastava Ved Prakash Singh Ashish Kumar Tewari Carmen Puerta Pedro Valerga 《Journal of Molecular Structure》2012
Single crystal X-ray structure analysis of 5-(2-benzoimidazole-1-yl-ethoxy)-3-methyl-1-phenyl-1H-pyrazole-4-carboxylic acid methyl ester (2).0.5H2O provided experimental proof for H?OC, CH?OH and HO?N interactions. The embedded water molecule bridges between molecules 2 via non-covalent interactions. Thus this molecule behaves as a preorganized host molecule for water, presenting a minimum ring-size molecular environment for water binding. Single crystal X-ray structure analysis of 5-(2-benzoimidazole-1-yl-ethoxy)-3-methyl-1-phenyl-1H-pyrazole-4-carboxylic acid methyl esterhemihydrate provided experimental proof for six hydrogen bonds by one molecule of water. The embedded water molecule bridges six molecules by two types of hydrogen bonding. Theoretical calculations showed that the conformation of the bicyclic hetero-ring alters only slightly due to the presence of the water molecule. Thus this organic molecule behaves as a very interesting preorganized host molecule for water, presenting maximum binding environment for water binding. 相似文献
134.
Priyanka Poddar Soma Mitra Md. Mabud Hossain Debasish Biswas Pradip N. Ghosh 《Molecular physics》2013,111(15):1957-1964
The line shape parameters of rovibrational transitions of water vapour belonging to the (2ν1 + ν2 + ν3) overtone band due to collisions between absorber molecules and noble gas helium have been measured in the spectral range between 11988.494 cm?1 and 12218.829 cm?1 using NIR diode laser spectrometer. In addition nitrogen and air broadening effects on some water vapour transitions belonging to the same band have also been studied. Wavelength modulation spectroscopy along with phase sensitive detection technique are used to record first derivative (1f) signal of buffer gas broadened water vapour transitions. Observed line shapes are fitted to standard Voigt profiles by non-linear least squares fitting program to extract the line shape parameters, like line strength and pressure broadening coefficients. The broadening effects induced by different types of buffer gases on water vapour line shapes are compared. Rotational quantum number (J) dependence of broadening coefficients of water vapour transitions is also examined. 相似文献
135.
Kaustubha Mendhurwar Harsh Sundani Priyanka Aggarwal Rabin Raut Vijay Devabhaktuni 《Analog Integrated Circuits and Signal Processing》2012,70(3):265-281
There has been a constant endeavor towards improving the available circuit design automation tools to match technological
advancements in the electronic industry. However, inadequate research efforts in the analog domain are holding back the exploitation
of advanced technologies. A dearth of design expertise in the analog domain is the principal driving force for the growth
of Design Automation (DA) tools. Transistor sizing is one of the most crucial steps in the analog IC design. In this paper,
we put forward a new computer aided design framework for the sizing of transistors in MOS Integrated Circuit (IC) amplifiers
by incorporating powerful modeling capabilities of Artificial Neural Networks (ANN). ANNs have proven to be efficient and
accurate modeling tools in several applications. The proposed tool is capable of directly computing transistor related design
parameters, of the MOS IC amplifier and associated peripheral circuitry. The proposed tool thus avoids several time-consuming
simulations and/or tuning runs at the very bottom level of analog IC amplifier implementation, using a given CMOS process.
It also reduces manual intervention in the design process, thus enhancing the automation of the design process. This paper
presents design examples of several analog IC functional modules that are developed and verified successfully. 相似文献
136.
The output fluorescence exhibited by an intramolecular charge transfer fluorescent probe 1 providing different chemical inputs mimicked multiple logic gates. A molecular keypad lock security device authorizing password entries (logic memory) and capable of solving crossword puzzles has been constructed by computing the output emission of 1 upon chemical inputs of BSA and Hg(2+). Based on logic operations the devised fluorescent keypad lock could be unlocked upon entering a correct sequence of password, 'BHU'. 相似文献
137.
Priyanka Verma Aranya B. Bhattacherjee Man Mohan 《Central European Journal of Physics》2012,10(2):335-341
In this work, we study parametric excitations in an elongated cigar-shaped BEC in a combined harmonic trap and a time dependent
optical lattice by using numerical techniques. We show that there exists a relative competition between the harmonic trap
which tries to spatially localize the BEC and the time varying optical lattice which tries to delocalize the BEC. This competition
gives rise to parametric excitations (oscillations of the BEC width). Regular oscillations disappear when one of the competing
factors, i.e. the strength of harmonic trap or the strength of optical lattice, dominates. Parametric instabilities (chaotic
dynamics) arise for large variations in the strength of the optical lattice. 相似文献
138.
L. N. Rai Priyanka Rai V. K. Singh 《International Journal of Theoretical Physics》2012,51(5):1572-1578
The paper presents an exact solution of spatially homogeneous and anisotropic cylindrically symmetric cosmological model in
Barber’s second self-creation theory of gravitation in the presence of perfect fluid with pressure equal to energy density.
Some physical properties of this model are also discussed. 相似文献
139.
Condensation product (L) of salicylaldehyde and semicarbazide behaves as a fluorescent sensor for Cd2+ ion, in 1:1 DMSO:H2O, over Mn2+, Fe2+, Ni2+, Co2+, Cu2+, Pb2+ and Hg2+ ions. The emission peak of L at λmax = 520 nm, on excitation with 420 nm wavelength photons, showed an enhancement in intensity of ca 60-fold when interacted with Cd2+ ion. The intensity was however found to remain unaltered when interacted with metal ions—Mn2+, Fe2+, Ni2+, Co2+, Cu2+, Pb2+ and Hg2+. The intensity increases by approximately 20 fold on interaction with Zn2+ ion. The increase in the fluorescent peak can be explained on the basis of photo induced electron transfer (PET) mechanism.
A 1:1 complexation between Cd2+ and L with log β = 4.25 has been proved. 相似文献
140.
Subhash Chand Priyanka Kaushal Jozef Osvald 《Materials Science in Semiconductor Processing》2013,16(2):454-460
The Poisson’s equation and drift–diffusion equations are used to simulate the current–voltage characteristics of Schottky diode with an inverse doped surface layer. The potential inside the bulk semiconductor near the metal–semiconductor contact is estimated by simultaneously solving these equations, and current as a function of bias through the Schottky diode is calculated for various inverse layer thicknesses and doping concentrations. The Schottky diode parameters are then extracted by fitting of simulated current–voltage data into thermionic emission diffusion equation. The obtained diode parameters are analyzed to study the effect of inverse layer thickness and doping concentration on the Schottky diode parameters and its behavior at low temperatures. It is shown that increase in inverse layer thickness and its doping concentration give rise to Schottky barrier height enhancement and a change in the ideality factor. The temperature dependences of Schottky barrier height and ideality factor are studied. The effect of temperature dependence of carrier mobility on the Schottky diode characteristics is also discussed. 相似文献