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91.
In the present paper, we consider Mond-Weir type nondifferentiable second order fractional symmetric dual programs over arbitrary cones and derive duality results under second order K?F-convexity/K?F-pseudoconvexity assumptions. Our results generalize several known results in the literature. 相似文献
92.
93.
The present study investigates the utility of composite beads of nano-particles of iron oxide and chitosan for removing Ni (II) ions from aqueous solution by batch and column adsorption techniques. In the batch mode experiment, the influence of pH, concentration, adsorbent dose, temperature, column mode, bed height, flow rate and initial concentration were studied on the adsorption profiles of nickel ions. The maximum uptake of Ni (II) ions was obtained at pH 4.0 in 30 min at room temperature. 相似文献
94.
An unprecedented conversion of thioalkyl/aryl glycoside to the corresponding 1‐O‐acetates has been described using acetic anhydride and HClO4‐SiO2 at rt. Although this transformation does not play an important role in the oligosaccharide synthesis in comparison to its reverse transformation, this gives useful information in selecting the reaction condition for the synthesis of oligosaccharides. The yields were excellent in all cases. 相似文献
95.
Manoj Kumar Santosh Kumar Tiwari Sheela Srivastava 《Applied biochemistry and biotechnology》2010,160(1):40-49
Enterocin LR/6, a bacteriocin obtained from the culture filtrate of Enterococcus faecium strain LR/6, has been purified to homogeneity using ammonium sulfate precipitation, cation-exchange chromatography, gel-filtration,
and checked on reverse-phase high-performance liquid chromatography. It is active at high temperatures (boiling as well as
autoclaving) and over a wide range of pH (2.0–8.0). Also, it is sensitive to a number of proteolytic enzymes but is stable
in the presence of surfactants and organic solvents. The protein could be stored at least up to 1 year at low temperatures
(4 °C and −20 °C) without any loss of activity. The N-terminal sequence of enterocin LR/6 showed no homology with known enterocins
or other bacteriocins present in the database, suggesting it to be a novel enterocin. Matrix-assisted laser desorption/ionization-time-of-flight
mass spectrometry and tricine sodium dodecyl sulfate-polyacrylamide gel electrophoresis analysis revealed its mass to be ∼6.1 kDa.
It showed a bactericidal mode of action against indicator strain, Micrococcus luteus. 相似文献
96.
97.
Incident primary beam divergence is a source of systematic error in X-ray standing wave (XSW) characterization of single and multilayer thin films. Primary beam divergence significantly alters the XSW profile of a layered material and can lead to large errors when used with higher excitation energies. The present study suggests that when one uses Mo-Kalpha excitation, the primary beam divergence should be in range of 0.005(0). On the other hand, in the case of Cu-Kalpha excitation, primary beam divergence can be relaxed up to 0.01(0). 相似文献
98.
The influence of analyte mass concentration on determination of detection limits in X-ray fluorescence spectrometry has been investigated experimentally. Both the total reflection X-ray fluorescence (TXRF) and the conventional energy-dispersive X-ray fluorescence techniques have been used to derive the dependence of analyte mass concentration on the values of detection limits. Results obtained indicate that values of detection limits are optimum, or in other words, they are closer to the true detection limit of the technique, when analyte concentrations are in the range of 10 times of the detection limit. 相似文献
99.
A. K. Rastogi S. Mishra M. Nigam A. K. Tiwari 《International Journal of Infrared and Millimeter Waves》1994,15(10):1709-1720
Dispersion characteristics and wave impedance of trapped coupled image guides are computed by using mode matching techniques. Dispersion curves for trapped coupled image guide are plotted for various dielectric materials and dimensional parameters. The hybrid directional couplers in the above configuration have been theoretically designed by computing the normalization propagation constant. 相似文献
100.
We show that the velocity correlations in uniform dense granular flows inside a silo are similar to the hydrodynamic response of an elastic hard-sphere liquid. The measurements are made using a fluorescent refractive-index-matched interstitial fluid in a regime where the flow is dominated by grains in enduring contact and fluctuations scale with the distance traveled, independent of flow rate. The velocity autocorrelation function of the grains in the bulk shows a negative correlation at short time and slow oscillatory decay to zero similar to simple liquids. Weak spatial velocity correlations are observed over several grain diameters. The mean square displacements show an inflection point indicative of caging dynamics. The observed correlations are qualitatively different at the boundaries. 相似文献