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261.
We have demonstrated an efficient, compact, passively Q-switched single-mode diode-pumped Nd:YAG laser that uses Cr(4+):YAG as a saturable absorber. Linear- and ring-cavity configurations were demonstrated. Pulse energies and widths were, respectively, 1.5mJ and 3.9ns for the linear cavity and 2.1mJ and 12ns for the ring cavity. 相似文献
262.
This study extends the analysis of ref. [Hayat T, Ellahi R, Asghar S. The influence of variable viscosity and viscous dissipation on the non-Newtonian flow: An analytic solution, Commun Nonlinear Sci Numer Simul 2007;12:300–313] in a porous medium by employing modified Darcy’s law. Beside this Reynolds and Vogels models of temperature dependent viscosity are considered. The problem is solved using homotopy analysis method (HAM). Expressions of velocity and temperature profiles are constructed analytically and explained with the help of graphs. 相似文献
263.
Saima Aftab Sevinc Kurbanoglu Goksu Ozcelikay Afzal Shah Sibel A. Ozkan 《Electroanalysis》2019,31(6):1083-1094
In this study, a novel and sensitive electrochemical nanosensor for the determination of antipsychotic drug Pimozide (PZ) is proposed using NH2 functionalized multi walled carbon nanotubes (NH2fMWCNT) decorated with and ZnO nanoparticles (ZnONPs) co‐catalyzed by graphene quantum dots (GQDs). Prior to electrochemical analyses of PZ, the designed nanosensor was well characterized in terms of surface morphology by scanning electron microscopy (SEM) and SEM armed with EDX analysis. Electrochemical impedance spectroscopy (EIS) employed to investigate the electron transfer capability and cyclic voltammetry (CV) technique was used to successfully compare the redox response of PZ on the surface of modified and unmodified electrode. The designed nanosensor response was linear between 6.25×10?11–1.20×10?7 M concentration range of PZ with a limit of detection value as 1.02×10?11 M. The influence of interfering agents was further studied to examine the selectivity of the designed sensor. A rapid screening of PZ as is required in pharmaceutical and biological samples underscores the paramount importance of nano based electrochemical sensor for its sensitive and selective detection. 相似文献
264.
Shahid Adeel Khalid Mahmood Zia Muhammad Abdullah Mahwish Salman Mohammad Zuber 《Natural product research》2019,33(14):2060-2072
Natural products with therapeutic nature are nowadays warmly welcomed in textiles. Current study is concerned with isolation of tannin from neem bark (Azadirachta indica) and its application onto silk fabric. For improvement in shades, chemical & bio-mordants have been employed at optimal dyeing conditions. It is found that methanolic extract of pH 5 obtained 8 g dye powder after US Treatment for 30 min has given high color strength if used to dye irradiated silk for 65 min at 75 °C. Bio-mordanting using herbal plants has improved the color characteristics as compared to chemical mordants used. ISO standards for color fastness reveal that herbal based bio-mordants have improved the rating from good to excellent as compared to chemical mordants used. It is concluded that US treatment has not only isolate the colorant for neem bark under mild condition but also given excellent characteristic using bio mordants onto silk fabrics. 相似文献
265.
Afzal M. Yasmeen G. Saleem M. Butt P. K. Khattak A. K. Afzal J. 《Journal of Thermal Analysis and Calorimetry》2000,59(3):721-727
Zeolite-4A is a hydrated aluminosilicate which becomes more hydrated when exchanged with transition metals. In this work,
the dehydration kinetics of cobalt, nickel and copper(II)-exchanged zeolite-4A were studied by means of TG and DTA over the
temperature range from 20 to 500°C, and the numbers of water molecules in the metal-exchanged zeolite samples were calculated.
It was observed that, as the ionic radius of the hydrated metal increased, the number of water molecules also increased. The
loss of water from the zeolite samples generally occurred in the temperature range 100–300°C and was manifested in the DTA
graphs by an extended endothermic effect. The DTA curves demonstrated that the peak position shifted towards lower temperatures
as the metal concentration increased or, in other words, the water of hydration increased. The kinetic parameters (order of
reaction and activation energy) were calculated via the Coats and Redfern method. The process of dehydration was found to
follow first-order kinetics.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
266.
Current and future measurements for the total cross sections at E-811, PP2PP, CSM, FELIX, and TOTEMhave been analyzed using various models. In the light of this study an attempt has been made to focus on the behaviorof total cross section at very high energies. 相似文献
267.
H. Ahmad M. Afzal M. Saleem S. M. Hasany 《Journal of Radioanalytical and Nuclear Chemistry》1994,181(1):117-129
Adsorption of cobalt on lead dioxide from aqueous solutions has been studied in relation to shaking time, amount of adsorbent, pH, and concentration of the adsorbate. The data fitted very well Langmuir, Freundlich, and Dubinin-Radushkevich isotherms and their corresponding constants were calculated. In another set of experiments the influence of different anions and cations on the adsorption of cobalt under the optimum experimental conditions have been determined. EDTA, tartrate, citrate, thiocyanate, oxalate, U(VI), Al(III), Fe(III), Cr(III), and Th(IV), drastically reduced adsorption of cobalt. Therefore these anions and cations should be removed before adsorption of cobalt on lead dioxide. Adsorption of other metal ions on the oxide were measured under identical conditions. TheK
D values indicate that cobalt can be separated successfully from Hg(II), Ag(I), Ta(V), In(III) and Tc(VII). 相似文献
268.
S. C. Raisinghani Noor Afzal 《Zeitschrift für Angewandte Mathematik und Physik (ZAMP)》1976,19(1):471-482
Second-order thermal boundary-layer solutions are obtained for flow past a blunted wedge with constant wall temperature. Contributions
due to longitudinal curvature and displacement effect are obtained by employing the G?rtler power series method. The first
five terms of the series for each of the effects are computed. Since the region of validity of the results thus obtained is
restricted in the streamwise direction, Eulerization technique is used to extend the radius of convergence to infinity. 相似文献
269.
Yunus Khan T. M. Soudagar Manzoore Elahi. M. Kanchan Mithun Afzal Asif Banapurmath Nagaraj. R. Akram Naveed Mane Suresh D. Shahapurkar Kiran 《Journal of Thermal Analysis and Calorimetry》2020,141(1):511-532
Journal of Thermal Analysis and Calorimetry - With the growing demand of economically feasible, clean, and renewable energy, the use of solar photovoltaic (PV) systems is increasing. The PV panel... 相似文献
270.
Malak Azmat Ali Neda Alam Meena Sonbal Ali Sajad Ahmad Dar Afzal Khan G. Murtaza A. Laref 《International journal of quantum chemistry》2020,120(7):e26141
This first principles study explores the structural, electronic, optical, and thermoelectric properties of the CsTmCl3 halide perovskite using density functional theory. The structural and thermoelectric properties are calculated without considering the spin-orbit coupling (SOC), while both the electronic and optical properties are calculated with and without the SOC effect. A comparison of the results obtained with and without SOC reveals that inclusion of the SOC effect reduces the band gap from 1.18 to 0.99 eV due to shifting of the Tm-d states toward the Fermi level. However, direct nature of the band gap remains the same in both the cases. The effect of SOC on the optical properties is, however, only visible in shifting of the third characteristic peak to lower energies. Strong optical absorption in the visible and ultraviolet regions shows effectiveness of CsTmCl3 in the optical devices working in these regions. Moreover, the calculated transport properties reveal CsTmCl3 as a useful thermoelectric material at room temperature. 相似文献