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91.
Biocompatible organic acids and citrate-stabilized gold nanoparticles were interacted with nisin to generate robust antimicrobial agents, which display archetypical nisin activity even at elevated pH. 相似文献
92.
Aniruddha Deb M. Itou Y. Sakurai N. Hiraoka N. Sakai 《Radiation Physics and Chemistry》2001,61(3-6):545-546
The spin density of Heusler alloy Co2FeGa, has been studied using the Compton scattering technique with 274 keV circularly polarized synchrotron radiation in the high energy inelastic scattering beamline (BL08W), at SPring-8, Japan. The magnetic Compton profiles along the two principal directions [1 1 0] and [1 1 1] were measured. The spin profiles shows a good agreement with our FLAPW-GGA results, where the theoretical results were based on the ferromagnetic ground state. The 3d spin moment at the Co and the Fe site was found to be in excellent agreement with the earlier reported neutron diffraction measurements. 相似文献
93.
Ramakumar K. L. Saxena M. K. Deb S. B. 《Journal of Thermal Analysis and Calorimetry》2001,66(2):387-397
Experimental evaluation of the procedures adopted for heat capacity measurements employing differential scanning calorimetry
(DSC) has been carried out by taking nickel and sapphire as test samples. Among the various methodologies reported in literature,
the absolute dual step method was chosen for this purpose due to its simplicity and minimum number of measurements required.
By proper temperature and heat flux calibration employing indium as reference, it was possible to obtain the calibration factor
independent of temperature. This was ascertained by analysing other pure metals namely Sn, Zn, Cd, and Pb and determining
their melting temperatures and heats of melting. Various operator- and sample-dependent parameters such as heating rate, sample
mass, the structure of the sample, reproducibility and repeatability in the measurements were investigated. Heat capacities
of both nickel and sapphire have been determined using the above method. Further, the heat capacity of nickel has also been
determined
using the widely employed three-step method taking sapphire as the heat flux calibration standard. Both methods yielded the
comparable heat capacity values for nickel. Based on the parameters investigated and their influence, it could be concluded
that reasonably precise and accurate heat capacity measurements are possible with DSC. One advantage of this method is the
elimination of a separate calibration run using a reference material of known heat capacity.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
94.
Acrylic acid was grafted onto fluorinated ethylene propylene copolymer (FEP) using a simultaneous radiation technique and the resulting membranes were subsequently sulfonated. Thermal and mechanical properties of these membranes were investigated and were found to be strongly influenced by the degree of grafting. Thermogravimetric analysis (TGA) of these membranes showed that these membranes undergo multistep degradation unlike virgin FEP which degrades in a single step. Glass transition temperature and degree of crystallinity were determined by differential scanning calorimetry (DSC). Glass transition temperature increased while crystallinity decreased with increase in degree of grafting. Tensile strength and elongation at break were found to decrease on grafting and further on sulfonation. Copyright © 2004 John Wiley & Sons, Ltd. 相似文献
95.
In solving multi-objective optimization problems, evolutionary algorithms have been adequately applied to demonstrate that multiple and well-spread Pareto-optimal solutions can be found in a single simulation run. In this paper, we discuss and put together various different classical generating methods which are either quite well-known or are in oblivion due to publication in less accessible journals and some of which were even suggested before the inception of evolutionary methodologies. These generating methods specialize either in finding multiple Pareto-optimal solutions in a single simulation run or specialize in maintaining a good diversity by systematically solving a number of scalarizing problems. Most classical generating methodologies are classified into four groups mainly based on their working principles and one representative method from each group is chosen in the present study for a detailed discussion and for its performance comparison with a state-of-the-art evolutionary method. On visual comparisons of the efficient frontiers obtained for a number of two and three-objective test problems, the results bring out interesting insights about the strengths and weaknesses of these approaches. The results should motivate researchers to design hybrid multi-objective optimization algorithms which may be better than each of the individual methods. 相似文献
96.
N. Deb 《Journal of Thermal Analysis and Calorimetry》2005,81(1):61-65
Summary A mixed metal oxalate, manganese(II)bis(oxalato)nickelate(II)tetrahydrate, has been synthesized and characterized by elemental analysis, IR spectral and X-ray powder diffraction (XRD) studies. Thermal decomposition studies (TG, DTG and DTA) in air showed that the compound decomposed mainly to Mn2O3, MnO2 and NiO at ca.1000°C, via. the formation of several intermediates. DSC study in nitrogen upto 500°C showed the endothermic decomposition. The tentative mechanism for the thermal decomposition in air is proposed. 相似文献
97.
98.
Interpenetrating polymer networks (IPNs) based on carboxylated nitrile rubber (XNBR) and poly(methyl methacrylate)s were synthesized. Crosslinked XNBR was swollen in methyl methacrylate containing benzoyl peroxide as initiator and tetraethylene glycol dimethacrylate as crosslinking agent. The compositions of the IPNs were varied by changing the swelling time of the rubber in the methacrylate monomer. The dynamic mechanical properties of the IPNs were studied. The dynamic mechanical properties in the range 1–105 Hz were obtained by the time‐temperature superposition of the data under multifrequency mode, which indicated high tan δ with good storage modulus in the entire frequency range. This indicates the suitability of these IPNs as vibration and acoustic dampers. Copyright © 2002 John Wiley & Sons, Ltd. 相似文献
99.
Ions undergoing a reaction-diffusion process are susceptible to electric field. We show that a constant external field may induce a kind of instability on the state stabilized by diffusion in a reaction-diffusion system giving rise to formation of pattern even when the diffusion coefficients of the reactants are equal. The origin of the pattern is due to the difference in mobilities of the two species and is thus markedly different from that of deformed Turing pattern in presence of the field. While this differential flow instability had been shown earlier to result in traveling waves, we realize in the context of stationary pattern formation in a typical reaction-diffusion-advective system. Our analysis is based on a numerical simulation of a generic model on a two-dimensional domain. 相似文献
100.
Pramil C. Deb 《European Polymer Journal》1982,18(9):769-771
An extended mathematical analysis is proposed for free-radical polymerisation systems involving initiators which produce primary radicals that have quite long half-life and decompose to secondary radicals. Initiation and macroradical termination by both primary and secondary radicals have been considered. Data for styrene and vinyl chloride have been treated with the developed relationships; limitations of earlier treatments are discussed. 相似文献