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991.
992.
Handelsman Mitchell M.; Gottlieb Michael C.; Knapp Samuel 《Canadian Metallurgical Quarterly》2005,36(1):59
This article presents an approach to graduate (and professional) training that views becoming an ethical psychologist as an acculturation process. J. W. Berry's (1980, 2003) model of acculturation strategies is used as a framework for understanding ethical acculturation, a developmental process during which students can use several types of adaptation strategies. Students enter training with their own moral value traditions and concepts but are confronted with new ethical principles and rules, some of which may be inconsistent with their ethics of origin. The article explores several applications of the framework to ethics courses, practicum supervision, and other areas of training. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
993.
An experimental technique has recently been developed to characterize reactive metals, including plutonium (Pu) and cerium, using electron backscatter diffraction (EBSD). Microstructural characterization of Pu and its alloys by EBSD had been previously elusive primarily because of the extreme toxicity and rapid surface oxidation rate associated with Pu metal. The experimental technique, which included ion-sputtering the metal surface using a scanning Auger microprobe (SAM) followed by vacuum transfer of the sample from the SAM to the scanning electron microscope (SEM), used to obtain electron backscatter diffraction Kikuchi patterns and orientation maps for a Pu-gallium alloy is described and the initial microstructural observations based on the analysis are discussed. The phase transformation behavior between the δ (face-centered cubic) and ε (body-centered-cubic) structures is explained by combining the SEM and EBSD observations. 相似文献
994.
Yan Qu John R. Howell Ofodike A. Ezekoye 《Semiconductor Manufacturing, IEEE Transactions on》2007,20(1):39-50
Light-pipe radiation thermometers (LPRTs) are widely used to monitor temperature during thermal processing of materials, particularly semiconductor wafer rapid thermal processing. According to the International Technology Roadmap for Semiconductors 2004, temperatures for semiconductor wafer processing should be measurable to within an uncertainty of plusmn1.5 degC at 1000 degC with temperature calibration traceable to International Temperature Standard-90. To achieve this accuracy level, the radiation signal transport process inside the light-pipe probe has to be fully understood. Few studies have been conducted to model the radiation transfer of LPRTs. In this paper, a Monte Carlo model has been created to simulate the signal transport from the measurement surface through the light-pipe probe. The model predicts the acceptance angle or aperture of the light-pipe. We also investigated the effect of nonspecular reflections caused by the sidewall surface roughness of the light-pipe probe using this model 相似文献
995.
Bard K. Dewey B. Hsu M.-T. Mitchell T. Moody K. Rao V. Rose R. Soreff J. Washburn S. 《Proceedings of the IEEE. Institute of Electrical and Electronics Engineers》2007,95(3):530-554
IBM's high-performance microprocessor designs leverage internally developed electronic design automation tools to create high-frequency, power efficient, and robust microprocessors. This paper describes some of the tools employed in the custom circuit design methodology in IBM. The tools described include a transistor-level block-based static timer, a static noise analysis methodology, and a transistor width tuner that optimizes performance and area. We also describe the application of electrical rule checking used to enforce consistent design practices. Finally, we discuss a macro extraction tool that determines parasitic resistance and capacitance of interconnect from a layout 相似文献
996.
C. M. Cotell G. J. Yurek R. J. Hussey D. F. Mitchell M. J. Graham 《Oxidation of Metals》1990,34(3-4):201-216
The oxidation behavior of pure Cr and Cr implanted with Y was studied as a function of temperature (900 and 1025°C) and ion-implantation dose (1×1015 and 2×1016 Y ions/cm2). The microstructures of the Cr2O3 scales were affected by both of the variables studied. Yttrium ions segregated at the grain boundaries in the Cr2O3 scales formed on the implanted alloys and the concentration of Y at the grain boundaries decreased with a decrease in the dose of implanted Y. The mechanism of growth of the Cr2O3 scales was altered by the presence of the Y ions at the Cr2O3 grain boundaries only when a critical concentration of Y at the grain boundaries was exceeded. 相似文献
997.
Jesús Alonso Nazlin Howell Wenceslao Canet 《Journal of the science of food and agriculture》1997,75(3):352-358
Two pectinmethylesterase isoforms, PME I and PME II, have been separated and purified from persimmon using chromatography techniques. Both isoforms presented differences in molecular weight (PME I: 51 kDa, PME II: 30 kDa), isoelectric point (PME I: 8·4, PME II: 6·9) and Km values (PME I: 54 μg ml−1, PME II: 31 μg ml−1). They differed in their optimum pH and thermal stability, PME I being the more thermostable isoform. Both isoforms exhibited similar behaviour with respect to Ca2+ and Na+ concentrations and were strongly inhibited by CaCl2 concentrations of over 80 mM and by NaCl concentrations of over 500 mM . Both isoforms were activated by low concentrations of polygalacturonic acid and were competitively inhibited by D -galacturonic acid and high concentrations of polygalacturonic acid. ©1997 SCI 相似文献
998.
A strategy for performing a correlation-based visual inspection of an object in a workcell is described. As such the controller is required to tell the robot where to position the camera next, to tell the system which template to correlate with next and to alarm if a fault is detected. Such a strategy would be appropriate for a hybrid optical-electronic-based inspection system, and this application is discussed. 相似文献
999.
The availability of the natural gas futures contract offers industry participants the opportunity to enter into stable supply agreements with partners of known reliability even though both parties to the agreement have differing views on the timing and magnitude of price changes. Although the examples were based on agreements between a marketer and end user, the concepts work equally as well for agreements between marketers and LDCs, between producers and marketers, and for direct-purchase agreements between producers and LDCs or end users. 相似文献
1000.
N Errington G A Tucker J R Mitchell 《Journal of the science of food and agriculture》1998,76(4):515-519
Juices made from tomatoes containing antisense genes for the enzymes polygalacturonase (PG(as)) and pectin esterase isoform 2 (PE(as)) were compared to those made from normal fruit. The juice from the PG(as) fruit was thicker than that from the normal fruit. This increased viscosity was shown to develop in a time-dependent manner and may involve the continued action of PE in the juice post-homogenisation. The liquid phases of the juices did not differ greatly in viscosity and chemical composition indicating that it was the difference in the amount and nature of the solids that was responsible for the differences in consistency. Confocal microscopy and image analysis supported this hypothesis, showing that there were more intact cell-like structures present in the juice from genetically manipulated fruit. © 1998 SCI. 相似文献