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21.
Neural Computing and Applications - Marston’s load theory is commonly used for understanding the soil–conduit interaction. However, there are no practical methods available which can...  相似文献   
22.
A possible application of AgInTe2 for optoelectronic switching is reported. Alternating and direct current (a.c. and d.c.) response of the material has been studied over a wide frequency range (5 Hz to 1 MHz) through measurements of conductance, capacitance and photocurrent at different temperature and illumination levels. The switching/recovery time has been analysed in terms of time constant and found to be of the order of microseconds for this material. Higher frequencies of operation (>40 kHz) are preferable because, at such frequencies, becomes almost independent of illumination level and temperature. Furthermore, the switching speed can be conveniently controlled with d.c. bias applied across the sample. Elliott's CBH model has been satisfactorily used to explain the switching behaviour for AgInTe2.  相似文献   
23.
The specific heat at constant pressure, C p, of aluminum measured by Ditmars, Plint, and Shukla has been reduced to the volume V 0 appropriate for 0 K employing the Murnaghan equation. The C v0 thus obtained is compared with the theoretical C v0 calculated in the harmonic and the lowest-order anharmonic approximation from three different pseudopotentials (Harrison, Ashcroft, and Dagens-Rasolt-Taylor) as well as a phenomenological Morse potential. The higher-order ( 4) anharmonic contributions are calculated from the same nearest-neighbor Morse potential as in the lowest-order anharmonic theory. The role of the vacancy and the higher-order anharmonic contributions to C v0 has been examined and we conclude that the 4 contributions to C v0 are much smaller than the vacancy contribution. After removal of the vacancy contribution, the reduced C v0 is found to be in excellent agreement with the Ashcroft and Harrison pseudopotentials as well as the Morse potential including the 2 and 4 contributions to C v0.  相似文献   
24.
Summary  Over the past few years, the challenges of globalisation, consolidation and economical point of view have meant that manufacturers of epoxy formulations have to constantly improve their capability to meet the needs of customers. An active area for advancement is that of epoxy and polyamide resin with castor oil. Generally, people working in the coating industries are familiar with castor oil, but this paper provides information on the new use of castor oil in epoxy and polyamide resin. This novel product (castor oil-modified epoxy resin/castor oil-modified polyamide) provides a previously unattainable combination and improved flexibility and toughness to a variety of ambient cure applications. This communication will review the performance of these castor oil-modified epoxy and polyamide resin surface coatings and adhesives. Based on the results of this study, these systems offer some advantages without much affecting the traditional properties of epoxy and polyamide resin in a variety of applications.  相似文献   
25.
The promising potential of cloud computing and its convergence with technologies such as mobile computing, wireless networks, sensor technologies allows for creation and delivery of newer type of cloud services. In this paper, we advocate the use of cloud computing for the creation and management of cloud based health care services. As a representative case study, we design a Cloud Based Intelligent Health Care Service (CBIHCS) that performs real time monitoring of user health data for diagnosis of chronic illness such as diabetes. Advance body sensor components are utilized to gather user specific health data and store in cloud based storage repositories for subsequent analysis and classification. In addition, infrastructure level mechanisms are proposed to provide dynamic resource elasticity for CBIHCS. Experimental results demonstrate that classification accuracy of 92.59% is achieved with our prototype system and the predicted patterns of CPU usage offer better opportunities for adaptive resource elasticity.  相似文献   
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The fatty acids of seed oils of the Flacourtiaceae,Hydnocarpus anthelmintica, Caloncoba echinata andTaraktogenus kurzii, have been examined by a combination of capillary gas chromatography, silver ion high performance liquid chromatography and gas chromatography-mass spectrometry. In addition to the common range of cyclopentenyl fatty acids found in such oils, 13-cyclopent-2-enyltridec-4-enoic acid was a major component ofH. anthelmintica and was identified by mass spectrometry as its picolinyl ester and dimethyldisulphide adduct. It has not previously been found in nature. In the other seed oils, the isolated double bond in the corresponding fatty acid was in position 6, as expected. Similarly,cis-4-hexadecenoic acid and C16 and C18 cyclopentyl fatty acids were identified for the first time inH. anthelmintica. Iso- andanteiso-methylbranched fatty acids were present in trace amounts.  相似文献   
28.
The addition of a bifunctional monomer, triethylene glycol dimethacrylate (TEGDMA), to a grafting system containing 2-hydroxyethyl methacrylate (HEMA) and benzoin ethyl ether photoinitiator substantially increased the graft add-on of the unswollen and sodium hydroxide–swollen cotton cellulose. Grafting caused changes in the properties of the substrate such as moisture regain, the water of imbibition, and the dyeability with a direct and a reactive dye in accordance with the graft level. The observations have been explained in relation to structural changes in the grafted cotton. © 1994 John Wiley & Sons, Inc.  相似文献   
29.
The ultrasonic velocity and density measurements of europium soaps in a mixture of benzene and methanol (3:2, vol/vol) were used to evaluate various acoustic parameters and molar volume and to determine the critical micelle concentration. The results showed that the ultrasonic velocity, specific acoustic impedance, molar sound velocity, and molar compressibility increase, and intermolecular free length, adiabatic Compressibility, and relative association decrease with increasing concentration and chainlength of the soap. The results were interpreted in terms of soap-solvent interaction.  相似文献   
30.
The simulation and experimental studies of an aperture‐coupled wideband dual segment rectangular dielectric resonator antenna with metamaterial for C‐band applications are presented in this paper. The antenna consists of Alumina (Al2O3) ceramic as upper segment and Teflon as lower segment. The combination of circular‐shaped coplanar split‐ring resonator and conducting strip has been used as metamaterial superstrate. With the use of metamaterial superstrate, the bandwidth of the antenna is increased by 48% through simulation and 22% experimentally. The broadside radiation pattern of the antenna is converted into directive radiation pattern with reduced beamwidth when metamaterial superstrate is used. The peak gain of the antenna is also enhanced by 33% through simulation and 31% experimentally with the use of metamaterial superstrate. © 2014 Wiley Periodicals, Inc. Int J RF and Microwave CAE 24:646–655, 2014.  相似文献   
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