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21.
Riju Khandaker M. Kamruzzaman M. Afrose R. Rahman M. Khan M. K. R. Liton M. N. H. Helal M. A. Anam T. K. Rahman M. M. 《Crystallography Reports》2020,65(6):968-979
Crystallography Reports - Transition metals doped FeS2 thin films are promising materials for optoelectronics, energy saving and storage applications. This is a first time report on the... 相似文献
22.
Ratios for target Ar K-shell ionization associated with single and double electron capture, as well as the ratios corresponding to total capture and the projectile K x rays, were determined for 1.8- to 2.2-MeV/u F7 + ,8 + ,9+ projectiles. This work was performed at Western Michigan University with the tandem Van de Graaff accelerator. Coincidences between emitted K-shell X-rays (both target and projectile) and the corresponding charge-changed particles were observed. The F9+ Ar K X-ray coincidence ratios for double to single capture are found to well exceed unity over the limited energy range of the measurements. Possible explanations for this anomalous behavior are discussed. 相似文献
23.
López-Martín J Anam EM Boira H Sanz MJ Blázquez MA 《Chemical & pharmaceutical bulletin》2002,50(12):1613-1615
Dennettine, a new 2,6-dimethoxychromone and three known phenanthrene alkaloids (uvariopsine, stephenanthrine and argentinine) in addition to the phenolic and known compound vanillin were isolated from the roots of Dennettia tripetala. Their structures were determined by physical and spectroscopical one dimensional (1D) and 2D-NMR analysis, including heteronuclear multiple bond correlation and nuclear Overhauser enhancement spectroscopy. 相似文献
24.
T.?HayatEmail author K.?Hutter S.?Nadeem S.?Asghar 《Zeitschrift für Angewandte Mathematik und Physik (ZAMP)》2004,55(4):626-641
The purpose of this work is to investigate the hydromagnetic oscillatory flow of a fluid
bounded by a porous plate, when the entire system rotates about an axis normal to the plate. The
fluid is assumed to be non-Newtonian (second grade), incompressible and electrically conducting.
The magnetic field is applied transversely to the direction of the flow. Such a flow model has
great significance not only of its theoretical interest, but also for applications to geophysics
and engineering. The resulting initial value problem has been solved analytically for steady and
unsteady cases. The analysis of the obtained results showed that the flow field is appreciably
influenced by the material parameter of the second grade fluid, the applied magnetic field, the
imposed frequency, rotation and suction and blowing parameters. It is observed in a second grade
fluid that a steady asymptotic hydromagnetic solution exists for blowing and resonance which is
different from the hydrodynamic situation. 相似文献
25.
26.
Summary Love wave travelling in a layer of uniform thickness overlying a half-space is assumed to be incident on two parallel but
staggered perfectly weak half-planes lying in the upper layer. The diffracted field is calculated using the modified Wiener-Hopf
technique and contour integration method. The diffracted waves satisfy the dispersion relations appropriate to different regions
formed by the perfectly weak half-planes.
To the memory of M. H. Kazi 相似文献
27.
Summary The problem of calculating the field within imperfectly conducting parallel-plates is considered. The solution in closed form is obtained using the Wiener-Hopf technique. The comparison has been made with that of perfectly conducting parallel plates waveguide.
Zusammenfassung Das Problem der Feldberechnung in unvollständig leitenden parallelen Platten wird betrachtet. Die Lösung in geschlossener Form wird mittels der Wiener-Hopf Technik gefunden, sowie ein Vergleich mit der Lösung für vollständig leitende Parallelplatten-Wellenleiter durchgeführt.相似文献
28.
Exact analytical solutions for a class of unsteady unidirectional flows of an incompressible second-order fluid are constructed. The flows are generated impulsively from rest by motion of a plate or two plates or by sudden application of a pressure gradient. Expressions for velocity, flux and skin friction are obtained for both large and small times. It is found that large and small times solutions are dependent on the coefficient of viscoelasticity. The solutions corresponding to Newtonian fluids can be easily obtained from those for fluids of second order by letting the viscoelastic parameter to be zero. 相似文献
29.
A simple, fast, reproducible (2.5% RSD at 3.0 μg/L), and sensitive method is described for quantifying As(III) (0.3 μg/L detection limit, 0.5–440 μg/L dynamic range). Anodic stripping voltammetry (ASV) is performed after accumulating arsenic at a mercury film electrode at ?0.350 V vs. Ag/AgCl (saturated KCl) for 20 s in 0.2 M HCl containing 8 μM ammonium 2‐amino‐1‐cyclopentene‐1‐dithiocarboxylate (AACD), without oxygen removal. This is the first report of using AACD in ASV and in electrochemical quantification of As(III). Total arsenic is determined after sodium‐sulfite‐reduction of As(V) to As(III). Interferences are minimal. Method validation involved water and metal alloy samples. 相似文献
30.
Ali Asghar Rastegari Abdol-Khalegh Bordbar Vajihe Mehnati-Najafabadi 《Cellulose (London, England)》2010,17(6):1213-1225
The present study evaluates the binding of cetylpyridinium chloride (CPC) with cellulase in various experimental conditions
using potentiometric, fluorescence spectroscopy and turbidimetric techniques. The analysis of binding curves revealed the
existence of two sets of binding sets for CPC. The binding parameters were estimated and interpreted in terms of structural
viewpoints of cellulase. The observation of turbidity suggests that CPC molecules individually nucleate around cellulase/CMC
complex to form micelle-like structures. Fluorescence spectroscopy analysis of cellulase/CMC-surfactant system showed that
these complexes could be compact to elucidate the mechanism of binding cellulase/CMC complex to CPC. The differential response
of the enzyme/CMC to surfactant, indicates that the interaction on the complex surface is strongly ionic and hydrophobic(cooperative)
in nature. A sequencing analysis was also conducted on β-1, 4-endoglucanase from A. niger (EglA) and others from family 12 in order to examine the nature of interaction involved in binding process and structure
of carbohydrate-protein complexes. The results suggest that the conserved residues are located in a more hydrophobic microenvironment
and apolar area energy is more than polar within enzyme structure. 相似文献