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1.
Staker S.W. Holloway C.L. Bhobe A.U. Piket-May M. 《Electromagnetic Compatibility, IEEE Transactions on》2003,45(2):156-166
The alternating-direction implicit finite-difference time-domain (ADI-FDTD) technique is an unconditionally stable time-domain numerical scheme, allowing the /spl Delta/t time step to be increased beyond the Courant-Friedrichs-Lewy limit. Execution time of a simulation is inversely proportional to /spl Delta/t, and as such, increasing /spl Delta/t results in a decrease of execution time. The ADI-FDTD technique greatly increases the utility of the FDTD technique for electromagnetic compatibility problems. Once the basics of the ADI-FDTD technique are presented and the differences of the relative accuracy of ADI-FDTD and standard FDTD are discussed, the problems that benefit greatly from ADI-FDTD are described. A discussion is given on the true time savings of applying the ADI-FDTD technique. The feasibility of using higher order spatial and temporal techniques with ADI-FDTD is presented. The incorporation of frequency dependent material properties (material dispersion) into ADI-FDTD is also presented. The material dispersion scheme is implemented into a one-dimensional and three-dimensional problem space. The scheme is shown to be both accurate and unconditionally stable. 相似文献
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Graham J. Holloway 《Journal of Stored Products Research》1985,21(4):165-169
Acid fuchsin staining is widely used as a method for easy detection of egg plugs deposited by Sitophilus spp. The effect of increasing grain moisture content through staining on some life history characters of three geographical strains of Sitophilus oryzae was examined. The results show that staining increases development rate and survival from egg to adult and there is also a suggestion of a strain × treatment interaction. Factors requiring consideration if staining is carried out are discussed. 相似文献
4.
Lawrence E. Holloway Yu Gong Jeff Ashley 《Mathematics and computers in simulation》2006,70(5-6):275-286
This paper introduces the concepts of state observability and condition observability for condition systems, a class of systems composed of discrete state components which interact via discrete binary signals called conditions. Given a set of externally observed conditions, state observability implies that the state of the system can be determined from the observations, and condition observability implies that all unobserved input and output conditions of the system can be determined from the observations. In this paper, we present a class of systems which is state observable and condition observable. We present a method to synthesize an observer system to provide state and condition signal estimates for a single component subsystem. 相似文献
5.
Tea-tree oil (oil of Melaleuca alternifolia) has recently received much attention as a natural remedy for bacterial and fungal infections of the skin and mucosa. As with most naturally occurring agents, claims of effectiveness have been only anecdotal; however, several published studies have recently demonstrated tea-tree oil's antibacterial activity. This study was conducted to determine the activity of tea-tree oil against 58 clinical isolates: Candida albicans (n = 10), Trichophyton rubrum (n = 8), Trichophyton mentagrophytes (n = 9), Trichophyton tonsurans (n = 10), Aspergillus niger (n = 9), Penicillium species (n = 9), Epidermophyton floccosum (n = 2), and Microsporum gypsum (n = 1). Tea-tree oil showed inhibitory activity against all isolates tested except one strain of E floccosum. These in vitro results suggest that tea-tree oil may be useful in the treatment of yeast and fungal mucosal and skin infections. 相似文献
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A. C. Lanser G. R. List R. K. Holloway T. L. Mounts 《Journal of the American Oil Chemists' Society》1991,68(6):448-449
A user-interactive computer-assisted Fourier transform infrared (FTIR) method has been developed for estimation of free fatty
acids (FFA) in vegetable oil samples by deconvolution of the infrared (IR) absorbances corresponding to the triglyceride ester
and FFA carbonyl bonds. Peak areas were used to determine FFA as a percentage of the total carbonyl areas in weighed standards
of refined, bleached, deodorized soybean oil containing from 0 to 5% added oleic acid. These data for percent FFA by FTIR
were compared to corresponding FFA data obtained by two titration methods-the AOCS Official Method Ca 5a-40 and the Official
Method with a slight modification. Correlation coefficients were 0.999 for the Ca 5a-40, 0.999 for the modified and 0.989
for the FTIR methods. FFA in samples of crude soybean oils extracted from damaged beans (0.5 to 2.1% FFA) were measured by
FTIR and compared to data obtained by titration of the same samples (correlation coefficient, 0.869).
To whom correspondence should be addressed at National Center for Agricultural Utilization Research, Agriculture Research
Service, U.S. Department of Agriculture, 1815 North University Street, Peoria, IL 61604.
1The mention of firm names or trade products does not imply that they are endorsed or recommended by the U.S. Department of
Agriculture over other firms or similar products not mentioned. 相似文献
9.
Lipid products formed during desaturation of [1-14C] stearyl CoA by hen liver microsomes 总被引:1,自引:0,他引:1
A number of lipid products are formed during the desaturation of stearyl CoA by hen liver microsomes. This article presents an analysis of the products formed when [1-14C] stearyl CoA is incubated with hen liver microsomes for various time periods. [1-14C] Oleyl CoA was the first radioactive unsaturated product formed. Synthesis of phospholipids containing [1-14C] oleic acid occurs only after the desaturase activity has begun to decline. The specific radioactivity of [1-14C] oleyl CoA was similar to the specific radioactivity of [1-14C] stearyl CoA at all time periods tested. The specific radioactivities of [1-14C] oleic acid and phospholipids containing [1-14C] oleic acid were much lower than that of the [1-14C] stearyl CoA. 相似文献
10.
The differential capacitance of tantalum has been measured in a number of aqueous electrolyte solutions. The metal is generally covered with an oxide layer in solutions of simple inorganic anions and the electrode capacitance is 5–10 F cm–2. In solutions of oxalate anions the electrode capacitance is much higher and corresponds to that expected for a clean metal in contact with an aqueous solution. 相似文献