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排序方式: 共有555条查询结果,搜索用时 15 毫秒
51.
52.
Slaughter Jerel E.; Sinar Evan F.; Bachiochi Peter D. 《Canadian Metallurgical Quarterly》2002,87(2):333
This study examined the effects of plan content and previous experience with discrimination on Black respondents' reactions to affirmative action plans. Black engineering students (N=1,173) were randomly assigned to 1 of 6 plans implemented by a hypothetical organization and were asked to provide ratings of perceived fairness and intention to pursue a position at the organization. There were significant effects of plan content on perceived fairness and job pursuit intentions, Perceived fairness mediated the effect of content on intentions. Furthermore, previous experience with discrimination interacted with content to affect intentions. Individuals who had experienced relatively more discrimination in the workplace reported stronger intentions to pursue a position at an organization whose plan specified special training opportunities for minorities. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
53.
Evan F. Koenig 《Energy》1981,6(5):457-470
We examine three alternative methods by which electric utilities might take advantage of distributed thermal energy storage to smooth out their load profiles. These three methods are: (1) time-specific rates, (2) time-invariant rates with subsidized storage, and (3) direct load controls with no subsidies to storage. The optimal form of each of these policies is determined and relations indicating the relative desirability of each are developed. 相似文献
54.
Previous studies show that if acoustic startle stimuli are presented in pairs, then the reaction to the 2nd stimulus (S2) is reduced, with the size of the refractory decrement determined by the interstimulus interval and the relative intensity of the 1st stimulus (S1). If a neutral stimulus (p) is presented just prior to S1, then the reaction to S1 is similarly inhibited, revealing the phenomenon of prestimulus inhibition. In 2 experiments with male albino Holtzman rats (N = 24) it was found that suppression of the reflex to S2 by S1 was unaffected by prestimulus inhibition of S1 (i.e., reflex amplitudes associated with S2 were identical in pS1-S2 series and S1-S2 series). In contrast, a reduction in the intensity of S1 relative to S2 did reduce the effect of S1 on S2. These data indicate that prestimulus inhibition of the reflex to S1 does not result because the preliminary stimulus attenuates the sensory impact of S1. The inhibitory process may be presumed to have a central locus. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
55.
What can we learn from the spatial logic of collections of trees in the rainforest? Evan Greenberg of the EmTech programme at the Architectural Association (AA) School of Architecture in London and George Jeronimidis of the Centre for Biomimetics at the University of Reading combine forces to analyse the rainforest's morphology and its potential as an urban model. They suggest how the sectional height differentiation of trees could present a new way of thinking about urban organisation, accommodating varied microclimates, programmes and the city's infrastructural flows. 相似文献
56.
In this study, dissolved Kr and SF6 gases were used to determine various hydrogeological parameters of laboratory columns under water-saturated and partially saturated conditions as a function of the flow velocity. The dissolved gases behaved conservatively in saturated columns but were significantly retarded in unsaturated conditions as a direct function of the Henry's law constant (KH) and the ratio of column pore spaces filled with air and water (Vg/Vw). Lower aqueous diffusion coefficients for SF6 compared to that for Kr also resulted in significant rate-limited mass transport across gas-water interface. This effect was exacerbated at higher flow velocities as was indicated by the asymmetric shape of breakthrough curves, more so in the case of SF6. A nonequilibrium advective-dispersive transport model accurately described tracer breakthrough and was used to estimate parameters such as final Vg/Vw under partially saturated conditions and partitioning rates. Internally consistent model results were obtained for both dissolved gases despite the wide range in physical properties (e.g., KH and aqueous diffusion coefficients), suggesting that dissolved Kr and SF6 may be used in conjunction to delineate and validate aquifer characteristics simultaneously from a single pulse injection of the tracer. 相似文献
57.
Illicit trade in tobacco products presents a threat to public health because it undermines the use of tax and price policies, which are among the most effective mechanisms for reducing tobacco consumption. Parties to the WHO Framework Convention on Tobacco Control (FCTC) are in the final stages of negotiating a protocol aimed at strengthening international cooperation in the fight against illicit tobacco trade. While an effective multilateral response to illicit tobacco trade would make a significant contribution to global tobacco control, achieving this through the FCTC forum is challenging. First, while illicit tobacco trade is a health problem, the expertise, experience and capacity needed to combat illicit trade are not traditionally found in health agencies. The development of links with other agencies, both domestic and international, is critical to ensure both an effective response and an efficient use of limited governmental and non-governmental resources. Second, in many parts of the world, the tobacco industry cooperates closely with governments in the combating of illicit trade. This cooperation poses risks for tobacco control, particularly if relationships and norms of cooperation spill over into other areas of FCTC implementation. An examination of the industry's positioning suggests that it sees an opportunity to portray itself as 'legitimate' and 'responsible', a friend of governments, and a way to integrate itself into FCTC processes. This paper makes suggestions for moving forward in this challenging area towards ensuring that the approach taken actually reduces illicit tobacco trade, strengthens tobacco tax policies and does not operate to undermine the FCTC. 相似文献
58.
Biomass cofiring at Seward Station 总被引:3,自引:0,他引:3
Sithe Energies, under a cooperative agreement with EPRI, the US Department of Energy, the Biomass Interest Group (BIG) and the Upgraded Coal Interest Group (UCIG), has developed a demonstration of cofiring biomass with pulverized coal at the Seward Generating Station on Boiler #12. This demonstration, constructed and tested by Foster Wheeler Development Corporation (FWDC) included construction of a facility to receive, screen, store and transport sawdust into a front-fired pulverized coal boiler. This facility has several distinctive features including the sawdust receiving system, the silo storage for processed biomass, and the injection system using the centerpipe of the coal burners. The biomass is prepared separately and transported separately from the coal. The wood waste is then injected into the center of the coal flame and burned there for optimum biofuel performance.
This demonstration, involving an extended period of cofiring testing, is based upon successful parametric tests conducted in December, 1996 and July, 1997. These tests documented the impact of cofiring, in the short term, on capacity, efficiency and emissions. Those results are now being evaluated over a long-term period. Additionally, operational and maintenance issues are being addressed with this demonstration and modifications have been made to improve the handling of the fuel. This paper describes the cofiring system, and reviews progress to date with the combustion tests. 相似文献
59.
Kathryn I Pollak Cheryl A Oncken Isaac M Lipkus Bercedis L Peterson Geeta K Swamy Pamela K Pletsch Pauline Lyna Rebecca J Namenek Brouwer Laura J Fish Evan R Myers 《Nicotine & tobacco research》2006,8(4):547-554
Improvements in smoking cessation interventions for pregnant smokers are needed. One major step is to examine the potential effectiveness of nicotine replacement therapy (NRT). The potential benefits of providing pregnant women with NRT to help them quit smoking are still unknown; early interventions to test the effectiveness and efficacy are vital to advancing the field. This paper describes recruitment efforts for a multiclinic trial to test the effectiveness of NRT use in addition to behavioral therapy in promoting cessation during pregnancy. The biggest challenge is recruiting sufficient numbers of pregnant women. This paper discusses specific obstacles for recruitment and solutions. Knowing the potential pitfalls to recruiting pregnant women into these trials can lead to better studies and thus improved outcomes. 相似文献
60.
Inactivation of barotolerant Listeria monocytogenes in sausage by combination of high-pressure processing and food-grade additives 总被引:1,自引:0,他引:1
Food-grade additives were used to enhance the efficacy of high-pressure processing (HPP) against barotolerant Listeria monocytogenes. Three strains of L. monocytogenes (Scott A, OSY-8578, and OSY-328) were compared for their sensitivity to HPP, nisin, tert-butylhydroquinone (TBHQ), and their combination. Inactivation of these strains was evaluated in 0.2 M sodium phosphate buffer (pH 7.0) and commercially sterile sausage. A cell suspension of L. monocytogenes in buffer (10(9) CFU/ml) was treated with TBHQ at 100 ppm, nisin at 100 IU/ml, HPP at 400 MPa for 5 min, and combinations of these treatments. Populations of strains Scott A, OSY-8578, and OSY-328 decreased 3.9, 2.7, and 1.3 log with HPP alone and 6.4, 5.2, and 1.9 log with the HPP-TBHQ combination, respectively. Commercially sterile sausage was inoculated with the three L. monocytogenes strains (10(6) to 10(7) CFU/g) and treated with selected combinations of TBHQ (100 to 300 ppm), nisin (100 and 200 ppm), and HPP (600 MPa, 28 degrees C, 5 min). Samples were enriched to detect the viability of the pathogen after the treatments. Most of the samples treated with nisin, TBHQ, or their combination were positive for L. monocytogenes. HPP alone resulted in a modest decrease in the number of positive samples. L. monocytogenes was not detected in any of the inoculated commercial sausage samples after treatment with HPP-TBHQ or HPP-TBHQ-nisin combinations. These results suggest that addition of TBHQ or TBHQ plus nisin to sausage followed by in-package pressurization is a promising method for producing Listeria-free ready-to-eat products. 相似文献