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861.
A new criterion for shipping safety of activated carbons is developed which requires microcalorimetric measurements for its implementation. It is examined by making microcalorimetric measurements on a variety of commercial activated carbons. Results are compared with those for the same carbons according to the critical ignition temperature approach.  相似文献   
862.
Theory suggests that perceptions of overall fairness play an important role in the justice judgment process, yet overall fairness is insufficiently studied. We derived hypotheses from fairness heuristic theory, which proposes that perceptions of overall fairness are influenced by different types of justice, are more proximal predictors of responses than specific justice types, and are used to infer trust when trust certainty is low. Results from Study 1 (N = 1340) showed that employees' perceptions of overall fairness in relation to a senior management team mediated the relationships between specific types of justice and employee outcomes (e.g., affective commitment). In Study 2 (N = 881), these mediated effects were replicated and trust certainty moderated the effect of overall fairness on trust as hypothesized. Study 2 also showed that, relative to procedural and informational justice, distributive and interpersonal justice had stronger effects on overall fairness. To explore how the organizational context may have influenced these findings, we performed qualitative analyses in Study 3 (N = 268). Results suggested that, consistent with the quantitative findings from Study 2, some types of justice were more salient than others. We discuss the implications of our findings for theory, research, and practice. Copyright © 2008 John Wiley & Sons, Ltd.  相似文献   
863.
Our study investigated applicant characteristics in response to organizations incorporating an affirmative action policy (AAP) statement in recruitment material. Study participants (N = 217; White upper‐level management students) randomly received recruitment material containing one of three statements (e.g., affirmative action, equal employment opportunity (EEO), or no statement regarding affirmative action or EEO) and were asked to evaluate the attractiveness of the organization publicizing the designated policy. Results indicated that individuals responded negatively to AAPs in recruitment material because of prejudice attitudes, the perceived unfairness of such programs (which we relate to equity sensitivity), or in an attempt to protect their own self‐interest (which we relate to general self‐efficacy). Additionally, individuals' equity sensitivity and general self‐efficacy both moderated the relationship between racial prejudice and organizational attractiveness. Specifically, the negative relationships between participants' prejudice attitudes and the attractiveness of organizations publicizing an affirmative action policy were stronger for benevolents (persons tolerant of situations where they are under‐rewarded) and for persons low in self‐efficacy. Implications of our findings for organizational recruitment practices are discussed. Copyright © 2006 John Wiley & Sons, Ltd.  相似文献   
864.
We report a case of maternal uniparental disomy of chromosome 10 discovered after chorionic villus sampling (CVS). Direct preparations revealed mosaic trisomy 10, while cultured CVS cells, as well as amniotic fluid cells, showed only a normal 46,XY complement. DNA analysis using microsatellite markers showed both chromosomes 10 to have been inherited from the mother. The pregnancy was complicated by polyhydramnios. A phenotypically normal male infant of appropriate size was delivered by Caesarean section at 41 weeks' gestation. Since only the direct preparations showed trisomy 10, this case illustrates the importance of CVS direct preparations in the detection of pregnancies at risk of uniparental disomy (UPD). Although the increased frequency of confined placental mosaicism (CPM) diagnosed when direct preparations are performed has been viewed negatively, identification of both CPM and UPD may have biological and clinical significance for a pregnancy. Even though only a single case of maternal disomy 10 is reported here, the apparently normal phenotype provides evidence that there are no major imprinted loci on chromosome 10 that affect in utero growth and development. However, other potential effects such as mental retardation will require long-term follow-up of this as well as additional cases.  相似文献   
865.
A regionally segmented multimedia fate model for the European continent is described together with an illustrative steady-state case study examining the fate of gamma-HCH (lindane) based on 1998 emission data. The study builds on the regionally segmented BETR North America model structure and describes the regional segmentation and parameterisation for Europe. The European continent is described by a 5 degrees x5 degrees grid, leading to 50 regions together with four perimetric boxes representing regions buffering the European environment. Each zone comprises seven compartments including; upper and lower atmosphere, soil, vegetation, fresh water and sediment and coastal water. Inter-regions flows of air and water are described, exploiting information originating from GIS databases and other georeferenced data. The model is primarily designed to describe the fate of Persistent Organic Pollutants (POPs) within the European environment by examining chemical partitioning and degradation in each region, and inter-region transport either under steady-state conditions or fully dynamically. A test case scenario is presented which examines the fate of estimated spatially resolved atmospheric emissions of lindane throughout Europe within the lower atmosphere and surface soil compartments. In accordance with the predominant wind direction in Europe, the model predicts high concentrations close to the major sources as well as towards Central and Northeast regions. Elevated soil concentrations in Scandinavian soils provide further evidence of the potential of increased scavenging by forests and subsequent accumulation by organic-rich terrestrial surfaces. Initial model predictions have revealed a factor of 5-10 underestimation of lindane concentrations in the atmosphere. This is explained by an underestimation of source strength and/or an underestimation of European background levels. The model presented can further be used to predict deposition fluxes and chemical inventories, and it can also be adapted to provide characteristic travel distances and overall environmental persistence, which can be compared with other long-range transport prediction methods.  相似文献   
866.
Iron hydroxide supported onto porous diatomite (D-Fe) is a low-cost material with potential to remove arsenic from contaminated water due to its affinity for the arsenate ion. This affinity was tested under varying conditions of pH, contact time, iron content in D-Fe and the presence of competitive ions, silicate and phosphate. Batch and column experiments were conducted to derive adsorption isotherms and breakthrough behaviours (50 μg L?1) for an initial concentration of 1,000 μg L?1. Maximum capacity at pH 4 and 17 % iron was 18.12–40.82 mg of arsenic/g of D-Fe and at pH 4 and 10 % iron was 18.48–29.07 mg of arsenic/g of D-Fe. Adsorption decreased in the presence of phosphate and silicate ions. The difference in column adsorption behaviour between 10 % and 17 % iron was very pronounced, outweighing the impact of all other measured parameters. There was insufficient evidence of a correlation between iron content and arsenic content in isotherm experiments, suggesting that ion exchange is a negligible process occurring in arsenate adsorption using D-Fe nor is there co-precipitation of arsenate by rising iron content of the solute above saturation.  相似文献   
867.
This paper presents the first attempt to quantify the production, cycling, storage and loss of PAHs in the UK environment. Over 53 000 tonnes of sigmaPAHs (sum of 12 individual compounds) are estimated to reside in the contemporary UK environment, with soil being the major repository. If soils at contaminated sites are included, this estimate increases dramatically. Emission of PAHs to the UK atmosphere from primary combustion sources are estimated to be greater than 1000 tonnes sigmaPAHs per annum, with over 95% coming from domestic coal combustion, unregulated fires and vehicle emissions. It is estimated that approximately 210 tonnes of sigmaPAH are delivered to terrestrial surfaces each year via atmospheric deposition. Therefore, inputs of PAHs to the UK atmosphere outweigh the outputs by a factor of over 4. This may be explained by enhanced particulate deposition near point sources, PAH degradation in the atmosphere and transport away from the UK with prevailing winds. Disposal of waste residues is estimated to contribute a further 1000 tonnes of sigmaPAH per year to the terrestrial environment. It is illustrated that the use of creosote has the potential to release considerable quantities of PAHs to the UK environment. Temporal trends in PAH cycling are then considered. There is good evidence to suggest that air concentrations and fluxes to the UK surface are now lower than at any time throughout this century. Nonetheless, the UK sigmaPAH burden is still increasing at the present time, principally through retention by soils. However, there are marked differences in the behaviour of individual compounds: there is evidence, for example, that phenanthrene concentrations in soils have declined since the 1960s, although soil concentrations of benzo[a]pyrene and other heavier PAHs have continued to increase through this century. Volatilisation of low molecular weight PAHs accumulated in soils over previous decades may be making an important contribution to the current atmospheric burden. The major uncertainties identified by data on this budget are: (1) the lack of PAH concentrations in some environmental matrices; (2) the possible importance of contaminated soils as a major repository and source of PAHs; (3) the lack of emission data (especially vapour phase releases) for some PAH sources; (4) the importance of biodegradation and volatilisation as loss mechanisms for low molecular weight PAHs in soils; and (5) the importance of creosote use in the PAH cycle.  相似文献   
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