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121.
设计性能出色的全新3D电视可走"终南捷径",赛灵思介绍了其Spartan-6 FPGA消费显示套件和IP,可为DisplayPort设计带来方便. 相似文献
122.
Hawthorne SB Grabanski CB Miller DJ Kreitinger JP 《Environmental science & technology》2005,39(8):2795-2803
The U.S. Environmental Protection Agency (EPA) narcosis model for benthic organisms in polycyclic aromatic hydrocarbon (PAH) contaminated sediments requires the measurement of 18 parent PAHs and 16 groups of alkyl PAHs ("34" PAHs) in pore water with desired detection limits as low as nanograms per liter. Solid-phase microextraction (SPME) with gas chromatographic/mass spectrometric (GC/ MS) analysis can achieve such detection limits in small water samples, which greatly reduces the quantity of sediment pore water that has to be collected, shipped, stored, and prepared for analysis. Four sediments that ranged from urban background levels (50 mg/kg total "34" PAHs) to highly contaminated (10 000 mg/kg total PAHs) were used to develop SPME methodology for the "34" PAH determinations with only 1.5 mL of pore water per analysis. Pore water was obtained by centrifuging the wet sediment, and alum flocculation was used to remove colloids. Quantitative calibration was simplified by adding 15 two- to six-ring perdeuterated PAHs as internal standards to the water calibration standards and the pore water samples. Response factors for SPME followed by GC/MS were measured for 22 alkyl PAHs compared to their parent PAHs and used to calibrate for the 18 groups of alkyl PAHs. Dissolved organic carbon (DOC) ranging from 4 to 27 mg/L had no measurable effect on the freely dissolved concentrations of two- and three-ring PAHs. In contrast, 5-80% of the total dissolved four- to six-ring PAHs were associated with the DOC rather than being freely dissolved, corresponding to DOC/water partitioning coefficients (K(DOC)) with log K(DOC) values ranging from 4.1 (for fluoranthene) to 5.6 (for benzo[ghi]perylene). However, DOC-associated versus freely dissolved PAHs had no significant effect on the total "34" PAH concentrations or the sum of the "toxic units" (calculated bythe EPA protocol), since virtually all (86-99%) of the dissolved PAH concentrations and toxic units were contributed by two- and three-ring PAHs. 相似文献
123.
John C. Caygill Janis A. Jones Carol E. M. Ferber 《Journal of the science of food and agriculture》1981,32(6):601-607
Vegetable milks were prepared in the laboratory from mung bean [Vigna radiata (L.) Wilczek], cowpea [Vigna unguiculata (L.) Walpers] and chick-pea [Cicer arietinum (L.)] by homogenisation of a filtered aqueous extract of the ground legume with soya bean oil. Emulsions stable to pasteurisation were made from the first two. Pigeon pea [Cajanus cajan (L.)] and black gram [Vigna mungo (L.) Hepper)] were found to be unsuitable as bases for milks prepared by simple processing. The nitrogen, oil, sugar and ash contents of the first three legumes, and of milks prepared from them, were determined. Imitation milks are intended to resemble animal milks nutritionally, and whilst the contents of potassium and phosphorus were acceptable, these vegetable milks were low in sodium, calcium and zinc. The trypsin inhibitory activity, whilst low in comparison with soya milk, was partially stable to pasteurisation. The amino acid composition indicated that it would be desirable to complement legume proteins with cereal proteins to prepare vegetable milks. 相似文献
124.
D. Ciancio I. Carol G. Castellazzi 《International journal for numerical methods in engineering》2014,98(5):344-370
Zero‐thickness interface elements are used to model contact surfaces or potential cracks. In these cases, their elastic stiffness is often set extremely high to reproduce a rigid behavior. This paper shows that the values of the stress tractions at the nodes of these elements can be affected by an error. A new procedure is proposed here, consisting of adding some nondimensional coefficients (purely geometry‐dependent) to the values of the interface stiffness parameters. Thus doing, the accurate tractions at the interface nodes are recovered. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
125.
When it is not consumed, bread presents a major source of food waste, both in terms of the amount and its economic value. However, bread also possesses the characteristics of an ideal substrate for solid state fermentation. Yet nearly all wasted bread ends up in landfill sites, where it is converted into methane by anaerobic digestion. Governments are finally taking action and, according to the EU Landfill Directive, for example, biodegradable municipal waste disposed into landfills must be decreased to 35% of 1995 levels, by 2020. Solid state fermentation of waste bread for the production of value added products is a novel idea, which could help with the achievement of this target. In this study, glucoamylase and protease production from waste bread pieces, via solid state fermentation, was investigated in detail. The optimum fermentation conditions for enzyme production were evaluated as, 20 mm particle size, 1.8 (w/w, db) initial moisture ratio, and duration of 144 h. Under these conditions, glucoamylase and protease activities reached up to 114.0 and 83.2 U/g bread (db), respectively. This study confirms that waste bread could be successfully utilised as a primary raw material in cereal based biorefineries. 相似文献
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128.
Ethnicity and age issues: Attitudes affecting rehabilitation of individuals with spinal cord injury.
The individual with spinal cord injury, family, staff, and significant others bring attitudes regarding age and ethnicity into the rehabilitation team dynamic. Such preconceived attitudes may direct one's ability to be open to change and incorporate new information. The authors present 3 cases that highlight the bidirectional nature of bias challenges and the potential impact of bias issues on the hospital setting, staff, individual, family, and significant others. The bidirectional nature of bias challenges is illustrated with 2 cases of bias issues presented by individuals with spinal cord injury during hospitalization and with I case of bias impact on an individual health care provider. Interventions and strategies to maximize information sharing, education, and adjustment during hospitalization, discharge planning, and community living are discussed. Individuals may face increasing challenges in maximizing the derived benefit from both health care delivery and community services if personal bias plays a role in excluding qualified personnel from consideration. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
129.
McCrae Robert R.; Costa Paul T. Jr.; Terracciano Antonio; Parker Wayne D.; Mills Carol J.; De Fruyt Filip; Mervielde Ivan 《Canadian Metallurgical Quarterly》2002,83(6):1456
Three studies were conducted to assess mean level changes in personality traits during adolescence. Versions of the Revised NEO Personality Inventory (P. T. Costa, Jr., & R. R. McCrae, 1992a) were used to assess the 5 major personality factors. A 4-year longitudinal study of intellectually gifted students (N = 230) was supplemented by cross-sectional studies of nonselected American (N = 1,959) and Flemish (N = 789) adolescents. Personality factors were reasonably invariant across ages, although rank-order stability of individual differences was low. Neuroticism appeared to increase in girls, and Openness to Experience increased in both boys and girls; mean levels of Extraversion, Agreeableness, and Conscientiousness were stable. Results extend knowledge of the developmental curve of penalty traits backward from adulthood and help bridge the gap with child temperament studies. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
130.
Johnson Sheri L.; Cueller Amy K.; Ruggero Camilo; Winett-Perlman Carol; Goodnick Paul; White Richard; Miller Ivan 《Canadian Metallurgical Quarterly》2008,117(2):268
[Correction Notice: An erratum for this article was reported in Vol 117(3) of Journal of Abnormal Psychology (see record 2008-11014-022). In the aforementioned article, Amy K. Cuellar's last name was misspelled. The corrected list of author names is: Sheri L. Johnson, Amy K. Cuellar, Camilo Ruggero, Carol Winett-Perlman, Paul Goodnick, Richard White, and Ivan Miller.] To date, few prospective studies of life events and bipolar disorder are available, and even fewer have separately examined the role of life events in depression and mania. The goal of this study was to prospectively examine the role of negative and goal-attainment life events as predictors of the course of bipolar disorder. One hundred twenty-five individuals with bipolar I disorder were interviewed monthly for an average of 27 months. Negative and goal-attainment life events were assessed with the Life Events and Difficulties Schedule. Changes in symptoms were evaluated using the Modified Hamilton Rating Scale for Depression and the Bech-Rafaelsen Mania Scale. The clearest results were obtained for goal-attainment life events, which predicted increases in manic symptoms over time. Negative life events predicted increases in depressive symptoms within regression models but were not predictive within multilevel modeling of changes in depressive symptoms. Given different patterns for goal attainment and negative life events, it appears important to consider specific forms of life events in models of bipolar disorder. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献