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871.
Plastic carrier bags have been drawing the attention of the public and politicians. Different policy measures to reduce the environmental burden of these bags have been implemented and more are planned. The research analyzed the actual environmental aspects of consumption and use of plastic carrier bags and assessed the effectiveness of the proposed regulation in Israel. Since plastic bags are provided free of charge, people have a tendency to use these bags excessively, therefore a rigorous educational program should address this trend. However, the environmental load imposed by the bags is more a politically correct issue than an actual environmental hazard, and therefore the means for reducing their use should not include a high levy or total elimination of these bags.  相似文献   
872.
An accurate and reproducible method for the analysis of flurazepam hydrochloride in pharmaceutical preparations has been described. A simple and rapid isocratic HPLC elution method was employed which requires about 15 minutes to be performed. The percentage mean recovery of flurazepam hydrochloride in Dalmane capsules was found to be 100.67% + 1.23% of the declared amount  相似文献   
873.
The adsorption of Sb(V) ions from aqueous solutions onto commercially available activated alumina (AA) was investigated. AA has a much higher adsorption capacity than presently used adsorbents. Sb(V) ions are likely adsorbed through electrostatic attraction and/or specific adsorption mechanism, while the optimum pH is found in the range of 2.8–4.3. The Sb(V) ions adsorption capacities increase with increasing temperature. The addition of nitrate, acetate, arsenite, chloride, and silicate ions affected Sb(V) ions adsorption only slightly, while the coexisting ascorbate, arsenate, phosphate, sulfate, EDTA, tartrate, and citrate ions substantially depressed Sb(V) ions adsorption.  相似文献   
874.
Drawing from the structural perspective of social capital theory, this research investigates how internal and external advice network structures influence knowledge overlap and variety and, how these knowledge dimensions in turn influence group effectiveness. Findings from two studies on knowledge‐intensive groups indicate that different advice network structures are associated with knowledge overlap and knowledge variety, and only knowledge variety was significantly associated with group effectiveness. In addition, despite implicit understanding that advice networks aid performance through enhancing knowledge outcomes, only knowledge variety was found to mediate the relationship between external network and group effectiveness. Implications for theory and practice are discussed. Copyright © 2007 John Wiley & Sons, Ltd.  相似文献   
875.
An innovative process was studied for the destruction of 2,4‐dichlorophenol in water. The immiscible fluorinated solvent, inert and highly ozone soluble, was used as the solvent in the extraction‐ozonation system. Taguchi methods were applied in the design of experiments to identify the significant factors and establish the optimal combination of process parameters. The result indicate that this statistical technique can provide an extremely effective structured approach.  相似文献   
876.
Abstract

This paper reviews the development of pesticides as an agricultural and health tool and discusses the national and international implications of pesticide regulation. The need for scientific input to the legislative and regulative processes is explained. Appropriate legislation and regulatory structures are presented. Finally, the need for international cooperation in the use and control of pesticides is analyzed.  相似文献   
877.
878.
Abstract: Although there has been a call for the integration of behavioral ecology and conservation biology, there are few tools currently available to achieve this integration. Explicitly including information about behavioral strategies in population viability analyses may enhance the ability of conservation biologists to understand and estimate patterns of extinction risk. Nevertheless, most behavioral‐based PVA approaches require detailed individual‐based data that are rarely available for imperiled species. We present a mechanistic approach that incorporates spatial and demographic consequences of behavioral strategies into population models used for conservation. We developed a stage‐structured matrix model that includes the costs and benefits of movement associated with 2 habitat‐selection strategies (philopatry and direct assessment). Using a life table for California sea lions (Zalophus californianus), we explored the sensitivity of model predictions to the inclusion of these behavioral parameters. Including behavioral information dramatically changed predicted population sizes, model dynamics, and the expected distribution of individuals among sites. Estimated population sizes projected in 100 years diverged up to 1 order of magnitude among scenarios that assumed different movement behavior. Scenarios also exhibited different model dynamics that ranged from stable equilibria to cycles or extinction. These results suggest that inclusion of behavioral data in viability models may improve estimates of extinction risk for imperiled species. Our approach provides a simple method for incorporating spatial and demographic consequences of behavioral strategies into population models and may be easily extended to other species and behaviors to understand the mechanisms of population dynamics for imperiled populations.  相似文献   
879.
Data were collected from managers in 24 nations/territories on work locus of control (LOC), individualism–collectivism (I–C), and well‐being (job satisfaction, absence of psychological strain, and absence of physical strain). There were significant mean differences across samples on all five of these measures, and consistent with our hypothesis, at the ecological or sample mean level well‐being was associated with an internal locus of control. However, contrary to our hypothesis, well‐being was not associated with I–C, despite a strong correlation between I–C and LOC. Findings at the ecological level were consistent with the literature concerning the salutary effects of control on well‐being. Copyright © 2001 John Wiley & Sons, Ltd.  相似文献   
880.
A study has been conducted over a period of one year on measurements of air pollution in the Shuaiba Industrial Area (SIA) of Kuwait. The study included analysis of pollutant behaviour relative to the wind speed and direction. SIA comprises several large scale industries including three petroleum refineries, two power plants, two fertilizer plants, a cement plant, a chlorine and soda plant, a commercial harbour and two large oil loading terminals. Measurements of 15 parameters have been carried out every 5 minutes using a mobile laboratory fitted with an automatic calibrator and a data storage system. The pollutants studied include methane, non‐methane hydrocarbons (NMHC), carbon monoxide, carbon dioxide, nitrogen oxides (NO, NO2, and NO x ), sulphur dioxide, ozone and suspended dust. Meteorological parameters monitored simultaneously include wind speed and direction, air temperature, relative humidity, solar radiation, and barometric pressure. The air quality data collected using the mobile laboratory have been used to calculate the diurnal and monthly variations in the major primary and secondary pollutants. Distribution levels of these pollutants relative to wind direction and speed have also been used in the analysis. The results show large diurnal variations in some pollutant concentrations. Generally, two types of concentration variations have been found, depending on whether the species is a primary or a secondary pollutant. Diurnal variations with two maxima were observed in the concentrations of primary pollutants including NO, SO2, NMHC, CO and suspended dust, whereas a single maximum was observed for secondary pollutants such as O3and NO2. The monthly variations of SO2and NO x showed maximum values during the warm months. However, ozone showed a quite marked seasonal variation with maxima during spring and late summer and a minimum during the early summer. The results also indicated a common source for NO x , SO2, NMHC, CO and suspended dust to the North‐West (NW) of the monitoring station. Moreover for NO x and SO2, another less significant source is to the South‐South‐West (SSW) and South‐West (SW) of the monitoring station.  相似文献   
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