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131.
CuSi2P3 is a semiconductor having sphalerite structure with the space group F3 3m with random distribution of the copper and silicon atoms on the cation sites. Silicon is soluble in CuSi2P3 upto 3 moles to form CuSi2 + xP3 (x = 1, 2, 3) compounds in single phase. In continuation of our work on thermal expansion of ternary semiconductors, CuSi3P3 crystals have been grown by a modified Bridgman method. Using a Unicam high temperature camera, the precision lattice parameter and the coefficient of thermal expansion (CTE) of CuSi3P3 at various high temperatures have been evaluated from X-ray diffraction data. It has been found that the lattice parameter increases non-linearly while the coefficient of thermal expansion increases linearly with temperature. The results on thermal expansion of various semiconductors have been discussed in terms of their ionicities. 相似文献
132.
Reddy DC Bapuji AT Rao VS Himabindu V Ravinder S 《Journal of chromatographic science》2012,50(6):538-546
A rapid and high sensitive liquid chromatography-tandem mass spectrometry (LC-MS-MS) method was developed and validated for the quantification of zolpidem in human EDTA plasma using ondansetron (IS) as an internal standard. The analyte and IS were extracted from human plasma using ethyl acetate and separated on a C18 column (Inertsil-ODS, 5 μm, 4.6 × 50 mm) interfaced with a triple quadrupole tandem mass spectrometer. The mobile phase, which consisted of a mixture of methanol and 20 mM ammonium formate (pH 5.00 ± 0.05; 75:25 v/v), was injected at a flow rate of 0.40 mL/min. The retention times of zolpidem and IS were approximately 1.76 and 1.22. The LC run time was 3 min. The electrospray ionization source was operated in positive ion mode. Multiple reaction monitoring used the [M + H](+) ions m/z 308.13 → 235.21 for zolpidem and m/z 294.02 → 170.09 for the ondansetron, respectively. Five freeze-thaw cycles was established at -20 and -70°C.The linearity of the response/concentration curve was established in human EDTA plasma over the concentration range 0.10-149.83 ng/mL. The lower detection limit [(signal-to-noise (S/N) > 3] was 0.04 ng/mL and the lower limit of quantification (S/N > 10) was 0.10 ng/mL. This LC-MS-MS method was validated with intra-batch and inter-batch precision of 0.52-8.66.The intra-batch and inter-batch accuracy was 96.66-106.11. Recovery of zolpidem in human plasma was 87.00% and IS recovery was 81.60%. The primary pharmacokinetic parameters were T(max) (h) = (1.25 ± 0.725), C(max) (ng/mL) (127.80 ± 34.081), AUC(0→t), = (665.37 ± 320.982) and AUC(0→∞), 686.03 ± 342.952, respectively. 相似文献
133.
An analytical model to predict heat transfer rates to an incompressible fluid in turbulent flow, with fully developed velocity profile, between a heated plate and a parallel, insulated plate is developed. The model employs van Driest's mixing length expression near the wall, a constant eddy diffusivitiy in the core and a constant turbulent Prandtl number. An approximate solution obtained by employing Rayleigh-Ritz method is shown to compare well with the exact solution obtained by numerical integration of the differential equations. The results are compared with the available experimental data and analytical solutions.
Nomenclature A+ dimensionless constant in van Driest formula - a+ dimensionless distance from the wall after which the eddy diffusivity of momentum is constant - b half-gap of passage - b+ dimensionless half-gap=bu*/ - Cf skin friction coefficient - Cp constant pressure specific heat - d hydraulic mean diameter defined as 4xarea/perimeter=4b - h convective heat transfer coefficient - K+ dimensionless constant in van Driest formula - k fluid thermal conductivity - m mass flow rate of fluid - Nu Nusselt number hd/k - P pressure - Pr Prandtl number=/ - Prt turbulent Prandtl number=m/ - qw heat flux at wall - Re Reynolds number=vmd/ - T Temperature - u+ dimensionless velocity=Vx/u* - u* friction velocity= - Vx axial velocity - x axial distance from the entrance - x+ dimensionless distance=x/d - y distance from the heated wall - y+ dimensionless distance=yu*/ Greek Symbols thermal molecular diffusivity - function equal to (H+)/ - boundary layer thickness - H eddy diffusivity of heat - m eddy diffusivity of momentum - m0 uniform eddy diffusivity of momentum in the core - dimensionless temperature - T-Ti/qwd/k uniform heat flux - T-Tw/Ti-Tw uniform temperature - fluid kinematic viscosity - fluid density - fluid shearing stress - bulk mean temperature—fully developed region - fully developed transverse temperature profile Suffixes 1 fully developed - 2 in the entrance region - i at the inlet - m bulk mean value - w at the heated wall 相似文献
Anwendung der Rayleigh-Ritz-Methode auf die Wärmeübertragung bei erzwungener turbulenter Strömung
Zusammenfassung Es wird ein analytisches Modell zur Berechnung der Wärmeübertragung an ein inkompressibles Fluid in turbulenter Strömung mit voll ausgebildetem Geschwindigkeitsprofil zwischen einer beheizten Platte und einer dazu parallelen isolierten Platte angegeben. Das Modell verwendet van Driest's Ausdruck für die wandnahe Mischungslänge, eine konstante Wirbeldiffusivität im Kern und eine konstante turbulente PrandtlZahl. Eine Näherungslösung nach der Rayleigh-Ritz-Methode läßt sich gut mit der exakten Lösung vergleichen, die durch numerische Integration der Differentialgleichungen erhalten wurde. Die Ergebnisse werden mit verfügbaren Versuchswerten und analytischen Lösungen verglichen.
Nomenclature A+ dimensionless constant in van Driest formula - a+ dimensionless distance from the wall after which the eddy diffusivity of momentum is constant - b half-gap of passage - b+ dimensionless half-gap=bu*/ - Cf skin friction coefficient - Cp constant pressure specific heat - d hydraulic mean diameter defined as 4xarea/perimeter=4b - h convective heat transfer coefficient - K+ dimensionless constant in van Driest formula - k fluid thermal conductivity - m mass flow rate of fluid - Nu Nusselt number hd/k - P pressure - Pr Prandtl number=/ - Prt turbulent Prandtl number=m/ - qw heat flux at wall - Re Reynolds number=vmd/ - T Temperature - u+ dimensionless velocity=Vx/u* - u* friction velocity= - Vx axial velocity - x axial distance from the entrance - x+ dimensionless distance=x/d - y distance from the heated wall - y+ dimensionless distance=yu*/ Greek Symbols thermal molecular diffusivity - function equal to (H+)/ - boundary layer thickness - H eddy diffusivity of heat - m eddy diffusivity of momentum - m0 uniform eddy diffusivity of momentum in the core - dimensionless temperature - T-Ti/qwd/k uniform heat flux - T-Tw/Ti-Tw uniform temperature - fluid kinematic viscosity - fluid density - fluid shearing stress - bulk mean temperature—fully developed region - fully developed transverse temperature profile Suffixes 1 fully developed - 2 in the entrance region - i at the inlet - m bulk mean value - w at the heated wall 相似文献
134.
G. Saravanan M. V. Suryanarayana M. J. Jadhav M. Ravikumar N. Someswararao P. V. R. Acharyulu 《Chromatographia》2007,66(5-6):431-434
This present work describes the development of a stability-indicating high performance liquid chromatographic method for the
quantitative determination of pemetrexed disodium. Pemetrexed disodium is an antifolate antineoplastic agent that exerts its
action by disrupting folate-dependent metabolic processes essential for cell replication. The chromatographic separation was
achieved on an ACE 3 C18 HPLC column using a mobile phase consisting of a mixture of buffer (solvent A) and organic modifier
acetonitrile (solvent B). Forced degradation studies were performed on bulk sample of pemetrexed disodium using acid (0.5 N
hydrochloric acid), base (0.5 N sodium hydroxide), oxidation (10% v/v hydrogen peroxide), heat (60 °C) and UV light (254 nm). Degradation of the drug substance was observed in base hydrolysis.
Degradation product formed under acid and base hydrolysis was found to be starting material. The stressed samples were assayed
using the developed LC method and the mass balance found was close to 99.5%, thus proving its stability-indicating power.
The developed method was validated with respect to linearity, accuracy, precision and robustness. 相似文献
135.
G. Saravanan B. M. Rao M. Ravikumar M. V. Suryanarayana N. Someswararao P. V. R. Acharyulu 《Chromatographia》2007,66(3-4):219-222
A stability-indicating HPLC method for the quantitative determination of Bicalutamide is described. Bicalutamide is a nonsteroidal
antiandrogen and is an oral medication that is used for treating prostate cancer. Separation was achieved on a Waters Symmetry
shield RP18 HPLC column using a mobile phase consists of a mixture of phosphate buffer (Solvent A) and organic modifier acetonitrile
(Solvent B). Degradation studies were performed on bulk samples of bicalutamide using acid (0.5 N methanolic hydrochloric
acid), base (0.5 N methanolic sodium hydroxide), oxidation (10% v/v methanolic hydrogen peroxide), heat (60 °C) and UV light
(254 nm). Degradation was observed under base hydrolysis to give the starting material used during the synthesis of bicalutamide.
The degraded samples were assayed and gave a mass balance greater than 99.5%, thus proving the stability-indicating power
of the developed method. The method was validated with respect to linearity, accuracy, precision and robustness. 相似文献
136.
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139.
Sylvia Badwar Reetuparna Ghosh Bioletty Mary Lawriniang Vibha Vansola Arjun Gopalakrishna Haladhara Naik Yeshwant Naik Saraswatula Venkata Suryanarayana Sanjay Yeshwant Salunkhe Arun Agarwal Shailaja Ware Anil Kumar Gupta Betylda Jyrwa Srinivasan Ganesan Pitambar Singh Ashok Goswami 《Journal of Radioanalytical and Nuclear Chemistry》2016,307(2):1385-1390
140.
Jagjeet Kaur Ravi Shrivastava Beena Jaykumar N. S. Suryanarayana 《Research on Chemical Intermediates》2014,40(1):317-343
This review includes research papers on different methods of preparation of Eu2+ and Dy3+-doped SrAl2O4 phosphors and papers reporting luminescence studies of the materials. The methods of preparation were compared and it was concluded that solid state reaction is the best method. Papers on characterization of these phosphors by X-ray diffraction and scanning electron microscopy are also discussed. The review ends with a few important conclusions. 相似文献