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101.
Daniel C. Crues Rajendran K. Raghavan Brent L. Adams 《Metallurgical and Materials Transactions A》1987,18(3):255-264
A self-consistent polycrystalline model developed by Kr?ner, and Budiansky and Wu (KBW) was used to model small strain (2
and 8 × 10-6) biaxial yield behavior in textured copper tubing. The results were compared to simulations using the Bishop-Hill model and
a lower bound (LB) model which neglected strain compatibility. It was found that the Bishop-Hill model poorly represents texture
effects whereas the KBW and LB models give accurate predictions of biaxial yield surfaces at these strain levels. A linear
latent hardening law was used with both the KBW and LB model. Varying the latent hardening ratio an order of magnitude had
little effect on the yield surface. Introducing the odd 1 coefficients of the generalized spherical harmonic expansion was
also found to have negligible effect on the predicted yield loci.
Formerly Graduate Student of Mechanical Engineering at Brigham Young University
Formerly Graduate Student of Materials Science and Engineering at the University of Florida 相似文献
102.
Brent Maundy David Westwick Stephan Gift 《International Journal of Circuit Theory and Applications》2008,36(1):81-108
This paper describes three circuits that implement pseudo‐logarithmic functions, which are simple and easy to implement. The circuits can be realized using operational amplifiers or current feedback amplifiers. Tuning can be achieved using switched resistors, or active resistors, or tunable transconductors, but are best suited for use with digitally switched resistors. Frequency response and stability considerations for two of the circuits are thoroughly discussed and PSPICE results confirming the theoretical results are presented alongside measured results. Copyright © 2007 John Wiley & Sons, Ltd. 相似文献
103.
T. Ishibashi K. Minami J. Jogo T. Nagatsuka H. Yuasa V. Smirnov Y. Kangawa A. Koukitu K. Sato 《Journal of Superconductivity》2005,18(1):79-82
Growth conditions for MnGeP2 thin films have been investigated by using molecular beam epitaxy (MBE) method. Mn and Ge were evaporated by K-cells, and P2 was supplied by decomposing tertialybutylphosphine (TBP). GaAs (001) and InP (001) single crystals were used as substrates. An X-ray diffraction peak, which can be assigned to (008) peak of MnGeP2, was observed at nearly the same position as the (004) peak of GaAs. The lattice constant of the MnGeP2 thin film was determined to be 1.13 nm assuming its crystal structure is a c-axis oriented chalcopyrite type structure. Secondary phases such as GeP, MnGex and MnP were observed for beam fluxes of Mn and Ge as high as 1×10–8 Torr. 相似文献
104.
A. Brent Bollong B.Sc. Roelof P. Bult M.Sc. 《JOM Journal of the Minerals, Metals and Materials Society》1989,41(7):39-41
High-purity tellurium is used in the preparation of II–VI compounds, particularly CdTe and Cdx Hg1?x Te. Distillation of tellurium under low-pressure H2 reduces the concentrations of iron and silicon. The addition of CdTe to tellurium prior to zone refining, in a quantity less than the eutectic concentration, has been observed to change the segregation behavior of Ca, K, Ga and As, which enables more efficient refining. Emission spectroscopy, spark source mass spectroscopy and the evaluation of Cd0.21Hg0.79 Te have been used to characterize these effects. 相似文献
105.
Tong-Tsung Wang Brent L. Adams Peter R. Morris 《Metallurgical and Materials Transactions A》1990,21(8):2223-2236
Spatial orientation coherence in 20 pct channel-die compressed aluminum ingot is investigated using the two-point orientation
coherence function (OCF) constructed from individual crystallite orientation measurements. It is found that orientation coherence
clusters formed in the initially coherence-free ingot during deformation. The orientation coherence cluster consists of a
central grain with lattice orientation (φ1, ϕ, φ2) surrounded by grains with lattice orientation (π + φ1, ϕ, φ2); this coincides with one of the processing-symmetry orientations of the central grain. The observed clustering is compared
with simulations of structure evolution based upon the classical full-constraint Taylor model. As is expected, no coherence
structure develops in these simulations. A mechanism of formation for the orientation coherence cluster is proposed based
upon a requirement of stress equilibrium between neighboring grains, while maintaining, on average, strain compatibility with
the overall plane-strain compression deformation mode. A simplified Fourier representation of the conditional two-point OCF
is described, and a numerical scheme to obtain the expansion coefficients is proposed and tested.
Formerly Visiting Scholar, Department of Mechanical Engineering, Brigham Young University, Provo, UT 84602, is retired. 相似文献
106.
This article serves as a comprehensive resource to help bridge the gap of cultural understanding for those using assertiveness training with ethnic minority clients. Therapists providing cross-cultural assertiveness training must be certain that gaining such skills is a value shared by the client and not imposed by the therapist. A more culturally appropriate approach includes the following general assessment strategies: determining the etiology of the lack of assertiveness; using self-report inventories that avoid words, slang, or situations that may not be meaningful to the client; and the developing norms for the cultural group for which the inventory will be used. General treatment strategies may include "message matching," backup assertion, and discriminative cue learning. Specific strategies that are relevant for each cultural group are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
107.
An AlGaAs/GaAs HBT direct-coupled amplifier has been designed and its characteristics described for the first time. The amplifier consists of two HBTs and three resistors without level-shift diodes. A superior amplifier performance of 11 dB gain with a 4 GHz bandwidth was obtained. 相似文献
108.
Susan Masten Brent Simpson Susan Hengemuehle Paramjeet Pati Alla Alpatova Boubacar Dembele 《臭氧:科学与工程》2015,37(1):29-35
Jatropha curcas is a well-known source of non-edible vegetable oil that is being promoted as an energy source and high quality feedstock in biodiesel production, especially in developing countries. The potential that the resulting seedcake by-product from jatropha oil extraction (?70% by volume) could also be used as a component in animal feed raises the prospect that a commercially viable jatropha-based industry could be developed. To date, however, the use of jatropha seedcake in livestock feed formulation has been constrained by the presence of phorbol esters (PE), which are known promutagenic and toxic compounds, and by the inability to eliminate PE by cost-effective means. Using seedcake by-product collected from a commercial facility in West Africa that processes jatropha biodiesel, this study demonstrates cost-effective measures of eliminating PE from jatropha seedcake using a combination of solar irradiation and ozonation. 相似文献
109.
T. Yaeshima S. Takahashi N. Ishibashi S. Shimamura 《International journal of food microbiology》1996,30(3):303-313
Sixteen strains of Bifidobacterium isolated from 15 dairy products such as yogurt, cultured milk, butter and cheese were characterized on the basis of phenotypic characteristics and DNA similarities were examined by a microplate hybridization method. Three of the strains were identified as Bifidodobacterium longum, one strain was identified as Bifidobacterium bifidm, and one strain was assigned to the species Bifidobacterium breve on the basis of phenotypic characteristics, and this identification was confirmed by the analysis of DNA similarities. The remaining 11 strains could not be identified by examining their phenotypic characteristics and, contrary to the product label information, these strains were identified as Bifudidobacterium animalis on the basis of DNA similarities. The applicability of the colorimetric hybridization method in micro dilution wells to genetic identification of Bifidobacterium species was also studied. 相似文献
110.
Phenol and catechol biodegradation by the haloalkaliphile Halomonas campisalis: influence of pH and salinity 总被引:1,自引:0,他引:1
Removal of aromatic compounds from alkaline and/or saline industrial wastewater is an environmental concern for industry. In addition, aromatics may be accumulating in soda lakes, unique natural systems, where the fate and toxicity of these contaminants is unknown. To determine the feasibility of aromatic compound biodegradation in saline and alkaline conditions, the effect of pH and salinity on the biodegradation of phenol as a model aromatic waste compound by the haloalkaliphilic bacterium Halomonas campisalis was examined. Phenol was degraded as a source of carbon and energy at pH 8-11 and 0-150 g/L NaCl. Metabolic intermediates catechol, cis,cis-muconate, and (+)-muconolactone were identified, thus indicating that phenol was degraded via the beta-ketoadipate metabolic pathway. Although phenol and catechol were completely degraded in all cases, small amounts of cis,cis-muconate accumulated proportionally to increases in pH. There was no noticeable influence of salinity on cis,cis-muconate accumulation except at 0 g/L NaCl where it was completely degraded. These results indicate that it may be feasible to use haloalkaliphiles forthe treatment of aromatics present in saline and/or alkaline systems. This is the first report of phenol and catechol biodegradation under combined saline and alkaline conditions. 相似文献