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101.
Read M.E. Nusinovich G.S. Dumbrajs O. Bird G. Hogge J.P. Kreischer K. Blank M. 《IEEE transactions on plasma science. IEEE Nuclear and Plasma Sciences Society》1996,24(3):586-595
A design for a 3-MW 140-GHz gyrotron based on the use of a coaxial cavity is given. The cavity mode is TE21,13, chosen so that the ohmic heating on both the inner and outer conductors would be low enough for CW operation. The mode selection process, nonlinear, multimode and time-dependent modeling of the beam wave interaction, and gun design are discussed in detail. An inverted magnetron injection gun (MIG) is used to accommodate the inner conductor. The radiation is coupled out via a quasi-optical mode converter, consisting of an irregular cylindrical waveguide section followed by a step-cut launching aperture and a single near-parabolic mirror. The design of these components is also described 相似文献
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R. Byron Bird 《Zeitschrift für Angewandte Mathematik und Physik (ZAMP)》1972,23(1):157-159
Summary It has been shown that the Oldroyd 6-constant model is incapable of describing the time-dependent rheological behavior of dilute suspensions of rigid dumbbells with Brownian motion. It is, however, possible to introduce two new terms into Oldroyd's equation, so that the time-dependent viscoelastic flows can be described correctly through second order; furthermore stationary flows can be described through the third order.Es wurde festgestellt, daß die Gleichung von Oldroyd nicht ausreicht, um das zeitabhängige rheologrsche Betragen verdünnter Suspensionen von starren Hanteln zu beschreiben. Es ist aber möglich, zwei neue Glieder in die Oldroydsche Gleichung einzuführen, um die zeitabhängigen viskoelastischen Strömungen von Hantelsuspensionen bis zur zweiten Ordnung richtig beschreiben zu können; außerdem können die stationären Strömungen bis zur dritten Ordnung angegeben werden. 相似文献
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Consumers' expressed Intentions-to-buy different brands are frequently measured in marketing research. Study of several hundred surveys shows that a relationship between the percentage I of consumers expressing such an Intention-to-buy and the percentage U claiming current Usage of the brand can be represented by a single one-parameter relationship I = K √U ± 3. This holds for different brands (large and small) in over 20 product-fields, for different demographic subgroups, for certain different definitions of the Intentions and Usage variables, for some American as well as British data, and even for trends over time.Both the nature of this relationship between I and U and the paradoxical finding that relatively few people express an Intention-to-buy a new brand which is sub-sequently successful and that relatively many people do so for a brand which is slowly dying are explained by the effect of past Usage. Methodological conclusions of the findings are indicated. 相似文献
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The distribution and conformation of very long-chain plant wax components in a lipid bilayer 总被引:1,自引:0,他引:1
Coll EP Kandt C Bird DA Samuels AL Tieleman DP 《The journal of physical chemistry. B》2007,111(30):8702-8704
Plant wax contains long-chain alkanes and related components which are transported to the surface of the plant by specialized ABC transporter proteins. Here, we determine the distribution and conformation of three wax components, nonacosane, nonacosan-15-one, and nonacosan-15-ol, using unbiased and umbrella sampling molecular dynamics simulations. The molecules all partitioned to the center of the bilayer, with a free-energy difference of -70 kJ/mol between bulk water and the center of the bilayer for the alkane and -55 kJ/mol for the two more-polar molecules. All of the wax molecules were highly mobile in the bilayer, freely moving between opposite leaflets on a time scale of a few nanoseconds. Nonacosan-15-one and nonacosan-15-ol folded double to expose their hydrophilic group to the solvent, whereas nonacosane alternated between orientations spanning the full bilayer and orientations in the center of the bilayer. 相似文献
108.
Philippa L. Ascough Craig J. Sturrock Michael I. Bird 《Isotopes in environmental and health studies》2013,49(1):64-77
We present the results of a study testing the response of two saprophytic white-rot fungi species, Pleurotus pulmonarius and Coriolus versicolor, to charred biomass (charcoal) as a growth substrate. We used a combination of optical microscopy, scanning electron microscopy, elemental abundance measurements, and isotope ratio mass spectrometry (13C and 15N) to investigate fungal colonisation of control and incubated samples of Scots Pine (Pinus sylvestris) wood, and charcoal from the same species produced at 300 °C and 400 °C. Both species of fungi colonise the surface and interior of wood and charcoals over time periods of less than 70 days; however, distinctly different growth forms are evident between the exterior and interior of the charcoal substrate, with hyphal penetration concentrated along lines of structural weakness. Although the fungi were able to degrade and metabolise the pine wood, charcoal does not form a readily available source of fungal nutrients at least for these species under the conditions used in this study. 相似文献
109.
Crowley E Bird P Fisher K Goetz K Benzinger MJ Agin J Goins D Johnson RL 《Journal of AOAC International》2011,94(6):1821-1834
The VIDAS Salmonella (SLM) Easy Salmonella method is a specific enzyme-linked fluorescent immunoassay performed in the automated VIDAS instrument. The VIDAS Easy Salmonella method is a simple 2-step enrichment procedure, using pre-enrichment followed by selective enrichment in a newly formulated broth, SX2 broth. This new method was compared in a multilaboratory collaborative study to the U.S. Food and Drug Administration's Bacteriological Analytical Manual, Chapter 5 method for five food matrixes (liquid egg, vanilla ice cream, spinach, raw shrimp, and peanut butter) and the U.S. Department of Agriculture's Microbiology Laboratory Guidebook 4.04 method for deli turkey. Each food type was artificially contaminated with Salmonella at three inoculation levels. A total of 15 laboratories representing government, academia, and industry, throughout the United States, participated. In this study, 1583 samples were analyzed, of which 792 were paired replicates and 791 were unpaired replicates. Of the 792 paired replicates, 285 were positive by both the VIDAS and reference methods. Of the 791 unpaired replicates, 341 were positive by the VIDAS method and 325 were positive by the cultural reference method. A Chi-square analysis of each of the six food types was performed at the three inoculation levels tested. For all foods evaluated, the VIDAS Easy SLM method demonstrated results comparable to those of the reference methods for the detection of Salmonella. 相似文献
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