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231.
This paper reviews selected research on classroom and school environments, using a framework that views schools from three perspectives—as places for learning, as places for socialization and as places for psychological development. Studies are included that deal with the impact of noise and classroom design on learning; the relationship between seating position, achievement and status; spatial cognition; the classroom environment and sex role stereotyping; privacy; and density. The need for classrooms to enhance children's feelings of competence, security and self-esteem is also stressed. The goal of the paper is to point out ways in which environmental psychologists can contribute to the improvement of the educational system and to the quality of life in schools.  相似文献   
232.
Risk decision-making in natural hazards encompasses a plethora of environmental, socio-economic and management-related factors, and benefits greatly from exploring possible patterns and relations among these multivariate factors. Artificial neural networks, capable of general pattern classifications, are potentially well suited for risk decision support in natural hazards. This paper reports an example that assesses the risk patterns or probabilities of house survival from bushfires using artificial neural networks, with a simulation data set based on the empirical study by Wilson and Ferguson (Predicting the probability of house survival during bushfires, Journal of Environmental Management 23 (1986) 259–270). The aim of this study was to re-model and predict the relationship between risk patterns of house survival and a series of independent variables. Various configurations for input and output variables were tested using neural networks. An approach for converting linguistic terms into crisp numbers was used to incorporate linguistic variables into the quantitative neural network analysis. After a series of tests, results show that neural networks are capable of predicting risk patterns under all tested configurations of input and output variables, with a great deal of flexibility. Risk-based mathematical functions, be they linear or non-linear, can be re-modelled using neural networks. Finally, the paper concludes that the artificial neural networks serve as a promising risk decision support tool in natural hazards.  相似文献   
233.
In recent years, volatile fatty acid (VFA) production through anaerobic fermentation of sewage sludge, instead of methane production, has been regarded as a high-value and promising roadmap for sludge stabilization and resource recovery. This review first presents the effects of some essential factors that influence VFA production and composition. In the second part, we present an extensive analysis of conventional pretreatment and co-fermentation strategies ultimately addressed to improving VFA production and composition. Also, the effectiveness of these approaches is summarized in terms of sludge degradation, hydrolysis rate, and VFA production and composition. According to published studies, it is concluded that some pretreatments such as alkaline and thermal pretreatment are the most effective ways to enhance VFA production from sewage sludge. The possible reasons for the improvement of VFA production by different methods are also discussed. Finally, this review also highlights several current technical challenges and opportunities in VFA production with spectrum control, and further related research is proposed.  相似文献   
234.
Females of the polychaete Polydora hoplura (Claparède 1869) that produced planktotrophic and adelphophagic larvae were compared genetically to determine whether the different reproductive morphs represented sibling species or poecilogony. Worms were collected from Saldanha Bay, South Africa (33°0′37.71S, 17°56′59.74E), and cultured in a laboratory setting from November 2012 to April 2013. The results based on mitochondrial and nuclear DNA (Cyt b and ATPSα, respectively) showed shared haplotypes between reproductive morphs for both markers. Additionally, variation in mtDNA sequences was significantly higher within morphs than between morphs (95.8 and 4.2 %, respectively). A comparison of developmental modes found that broods of planktotrophic larvae were larger than broods of adelphophagic larvae, while the latter had larger eggs and larvae at hatching. Developmental time from oviposition to settlement for planktotrophic and adelphophagic larvae was 40.2 and 16.6 days, respectively. Polydora hoplura represents the fifth confirmed case of poecilogony in the Spionidae.  相似文献   
235.
Ocean acidification is increasingly recognized as a component of global change that could have a wide range of impacts on marine organisms, the ecosystems they live in, and the goods and services they provide humankind. Assessment of these potential socio-economic impacts requires integrated efforts between biologists, chemists, oceanographers, economists and social scientists. But because ocean acidification is a new research area, significant knowledge gaps are preventing economists from estimating its welfare impacts. For instance, economic data on the impact of ocean acidification on significant markets such as fisheries, aquaculture and tourism are very limited (if not non-existent), and non-market valuation studies on this topic are not yet available. Our paper summarizes the current understanding of future OA impacts and sets out what further information is required for economists to assess socio-economic impacts of ocean acidification. Our aim is to provide clear directions for multidisciplinary collaborative research.  相似文献   
236.
Three treatment media, used for the removal of arsenic from drinking water, were sequentially extracted using 10 mM MgCl2(pH 8), 10 mM NaH2PO4(pH 7) followed by 10 mM (NH4)2C2O4(pH 3). The media were extracted using an on-line automated continuous extraction system which allowed the arsenic in each of the extraction fluids to be speciated on-line using IC-ICP-MS. The 10 mM MgCl2 preferentially extracted As(III) from each of the media. The percentage of the arsenic extracted by the MgCl2, relative to a HNO3/H2O2 digestion of the media, ranged from 0.1-2.3% for the three solids. The next sequential extraction fluid, 10 mM NaH2PO4, extracted some of the residual As(III) remaining on each of the media but the predominant species extracted was As(V). The 10 mM NaH2PO4 extracted 15.3 to 42.8% of the total arsenic relative to a total digested concentration for each of the media. The As(III) and As(V) stability studies conducted in these two extraction fluids indicated that conversion between As(III) and As(V) was not significant for the short extraction fluid sample contact time associated with the on-line continuous flow extraction cell. Finally, the 10 mM (NH4)2C2O4 extraction fluid was utilized in an off-line analysis mode because the Fe and As concentrations extracted from the media were not compatible with direct ICP-MS detection. The (NH4)2C2O4 extracted 2.9-29% As(III) for all three media and caused an oxidation of As(III) to As(V) during the extraction period for one of the three media. The sum of the arsenic from each of the three extraction fluids represented 92%, 44% and 53% of the available total arsenic for the three media, respectively. The speciation results for each media were obtained by adding all the speciation results from all three extraction fluids together and the resulting distribution of As(III)/As(V) compared well with the speciation results obtained via XANES.  相似文献   
237.
In this study, three possible improvements to a remediation process for chromated-copper-arsenate- (CCA) treated wood were evaluated. The process involves two steps: oxalic acid extraction of wood fiber followed by bacterial culture with Bacillus licheniformis CC01. The three potential improvements to the oxalic acid extraction step were (1) reusing oxalic acid for multiple extractions, (2) varying the ratio of oxalic acid to wood, and (3) using a noncommercial source of oxalic acid such as Aspergillus niger, which produces oxalic acid as a metabolic byproduct. Reusing oxalic acid for multiple extractions removed significant amounts of copper, chromium, and arsenic. Increasing the ratio of wood to acid caused a steady decline in metal removal. Aspergillus niger removed moderate amounts of copper, chromium, and arsenic from CCA-treated wood. Although A. niger was effective, culture medium costs are likely to offset any benefits. Repeated extraction with commercial oxalic acid appears to be the most cost-effective method tested for the two-step process.  相似文献   
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All known cosmic and geological conditions and laws of chemistry and thermodynamics allow that complex organic matter could have formed spontaneously on pristine planet Earth about 4,000 mya. Simple gasses and minerals on the surface and in oceans of the early Earth reacted and were eventually organized in supramolecular aggregates and enveloped cells that evolved into primitive forms of life. Chemical evolution, which preceded all species of extant organisms, is a fact. In this review, we have concentrated on experimental and theoretical research published over the last two decades, which has added a wealth of new details and helped to close gaps in our previous understanding of this multifaceted field. Recent exciting progress in the molecular and genetic analyses of existing life, in particular microorganisms of ancient origin, even supports the possibility that a cellular, self-reproducing common ancestor might be assembled and resurrected in anaerobic cultures at some time in the future. Charles Darwin did not, and indeed, could not, address and specify the earliest phases of life which preceded the Origin of Species. However, in a famous letter, he sketched “a warm little pond with all sorts of… (chemicals, in which) …a protein was chemically formed.” We try to trace the impact of his charming clear-sighted metaphor up to the present time.  相似文献   
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