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81.
M J Scotter S A Thorpe S L Reynolds L A Wilson D J Lewis 《Food Additives & Contaminants》1992,9(3):237-242
Retail samples of livers from calf (23), ox (18), lamb (17), pig (15), chicken (16) and turkey (1) were analysed to determine levels of vitamin A (all trans-retinol) and to aid assessment of the effects of using vitamin supplemented compound feedingstuffs for livestock. For comparison, 22 liver samples from lambs reared on diets not containing vitamin-supplemented compound feedingstuffs and four samples of liver from ox which had received supplemented feed but not during the last four months prior to slaughter were also analysed. The chosen method of analysis utilized saponification, solvent extraction and normal-phase high performance liquid chromatography with fluorescence detection. For all species analysed, the levels of vitamin A ranged from 10 to 1100 mg/kg, with all but seven at or below 400 mg/kg. For lamb and ox livers, the mean levels were 310 mg/kg and 200 mg/kg respectively for retail samples. The mean levels were 220 mg/kg (lamb) and 120 mg/kg (ox) in liver samples from animals fed controlled diets. The results are of the same order as those reported over recent years. 相似文献
82.
83.
Pietromonaco Paula R.; Rook Karen S.; Lewis Megan A. 《Canadian Metallurgical Quarterly》1992,63(2):247
Addressed conflicting views of depressives' interpersonal accuracy in an investigation of the accuracy of mild depressives (dysphorics) across differing social contexts. Women who were either friends or strangers and who were either similar or dissimilar in level of dysphoria conversed about 3 topics: a neutral topic, their own disclosure of a personal problem, and their partner's disclosure. Dysphorics were not more accurate in general than nondysphorics. After self-disclosure, all women more accurately detected sympathy from a similar stranger. After the partner's disclosure, women also better detected the mood of a similar partner. When interacting with nondysphoric strangers, however, dysphorics underestimated their partner's sympathy toward them. Implications for cognitive and interpersonal theories of depression and for depressives' relationships are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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86.
The authors describe an integrated processor that performs addition and subtraction of 30-b numbers in the logarithmic number system (LNS). This processor offers 5-MOPS performance in 3-μm CMOS technology, and is implemented in a two-chip set comprising 170 K transistors. Two techniques are used to achieve this precision in a moderate circuit area. Linear approximation of the LNS arithmetic functions using logarithmic arithmetic is shown to be simple due to the particular functions involved. A segmented approach to linear approximation minimizes the amount of table space required. Subsequent nonlinear compression of each lookup table leads to a further reduction in table size. The result is that a factor of 285 reduction in table size is achieved, compared to previous techniques. The circuit area of the implementation is minimized by optimizing the table parameters, using a computer program that accurately models ROM area. The implementation is highly pipelined, and produces one result per clock cycle using a ten-stage pipeline 相似文献
87.
Gary E. Wilson Derek C. Wadsworth Barry G. Miller Lewis Lommers Peter Kroeger Mitchell Olszewski Robert Kochan Ken Liebelt 《Nuclear Engineering and Design》1992,136(3)
The Modular High Temperature Gas-Cooled Reactor (MHTGR) is a candidate design for new production and commercial power nuclear reactors. The MHTGR has inherent safety features including: (1) passive shutdown and decay heat removal, (2) reduced requirements for operator intervention, thereby reducing sensitivity to operator error, and (3) long time intervals for corrective action. In support of the Department of Energy's (DOE) initial development of the design, the authors have completed an evaluation of the thermal-hydraulic phenomena that will dominate the plant response during representative normal, off-normal and accident conditions. Phenomena having significance to the plant behavior have been identified, and ranked with respect to their relative importance in satisfying operational, investment and/or safety criteria. The resulting information provides the basis for evaluating the applicability of existing computer codes, and defines the requirements for the development of new codes, for thermal-hydraulic systems analysis. The phenomena-based requirements also support the quality assurance related verification and validation of these codes. This paper briefly describes the methodology employed, and gives illustrative examples of the resulting requirements. References are cited for reports that document the full body of requirements and provide additional information for the methodology. 相似文献
88.
G.M. Lewis 《Thin》1991,12(2)
Standard commercial pallet racking is used in warehouses, factories, shops and a multitude of other places where palletised goods are to be stored. The structural analysis of this type of structure is complicated by the semi-rigid nature of the beam-to-upright connection, which is different from one manufacturer to another.In the present paper an attempt has been made to provide a simple design approach to the stability of pallet rack structures, and the effect that the form of the moment-rotation characteristic has on the type of stability demonstrated by the system.Finally the role of small imperfections is studied, and the effect that they have on the maximum load carrying capacity of the structure is shown. 相似文献
89.
The morphology of nickel crystals can be quantified using measurements of fractal structure. In the study described in this
article, fractal dimensions of cross sections of 16 nickel samples were determined, and the numerical analysis indicates that
the more rugged surfaces are characterized by higher fractal dimensions although the relationship between morphology and fractal
dimension is relatively weak. However, the data also show that fractal dimension is a better predictor of morphology than
apparent density, which is the measurement currently used. The nickel samples were also subjected to an avalanching disc technique
that has the potential to separate out the differences in flow in the different types of nickel powder. The differences in
flow between powders were ascribed to the similar gross morphologies of the particles, and the presence of shattered individual
particles in the mix.
For more information, contact A.E. Lewis, University of Cape Town, Precipitation and Crystallisation Research Facility, Department
of Chemical Engineering, Rondebosch, 7701, South Africa; +27-21-650-4091; fax +27-21-689-7479; e-mail alison@chemeng.uct.ac.za. 相似文献
90.
The Mean Opinion Scale (MOS) is a questionnaire used to obtain listeners' subjective assessments of synthetic speech. This paper documents the motivation, method, and results of six experiments conducted from 1999 to 2002 that investigated the psychometric properties of the MOS and expanded the range of speech characteristics it evaluates. Our initial experiments documented the reliability, validity, sensitivity, and factor structure of the P.L. Salza et al. (Acta Acustica, Vol. 82, pp. 650–656, 1996) MOS and used psychometric principles to revise and improve the scale. This work resulted in the MOS-Revised (MOS-R). Four subsequent experiments expanded the MOS-R beyond its previous focus on Intelligibility and Naturalness, to include measurement of the Prosody and Social Impression of synthetic voices. As a result of this work, we created the MOS-Expanded (MOS-X), a rating scale shown to be reliable, valid, and sensitive for high-quality evaluation of synthetic speech in applied industrial settings. 相似文献