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941.
942.
While the magnitude of potential consequences might vary, most hazards encountered in pilot plant operations are the same as those experienced in full scale commercial facilities. For example, safeguarding hazardous chemicals storage and transfer, protecting reaction vessels against catastrophic failure or runaways, all require careful consideration regardless of scale. We, however, want to address some aspects of pilot plants which can introduce hazards unique or more common to their operation. To illustrate, we present some case histories from our own pilot plant experience in BASF's Chemical Engineering Department, and include a brief discussion of some corresponding safeguards to mitigate these situations.  相似文献   
943.
944.
We investigate the economic feasibility of bioelectricity production from biomass in Malaysia and its impact on greenhouse gas (GHG) emissions and storage, agricultural prices, agricultural employment and deforestation. For this purpose, we develop a partial equilibrium model that projects agricultural prices, production, imports, exports, domestic consumption and land use in 5‐year increments between 2015 and 2065. Our results show that by 2030 biomass‐generated electricity can supply 36.5 per cent of the electricity generated in Malaysia, 16 times more than the 2016 electricity supply from biomass. Increased bioelectricity production from biomass will significantly reduce GHG emissions and will help Malaysia meet its commitment in the Paris Agreement to mitigate GHG emission by 45 per cent before 2030. Our modelling shows that biomass‐generated electricity creates a derived demand for waste biomass that expands the area of oil palm plantations. The expansion lowers agricultural prices, boosts agricultural employment and leads to some deforestation as landowners clear rainforest to plant oil palm trees. Nonetheless, the deforestation does not increase GHG emissions since GHG gains from bioelectricity significantly exceed GHG losses from deforestation.  相似文献   
945.
946.
BOOK REVIEWS     
Dynamics and Conflict in Regional Structura1 Change—Essay in Honor of Walter Isard Volume 2 Practical Methods of Regional Science and Empirical Applications—Selected Papers of Walter Isard, Volume 2 Department of Economics Loughborough University Export Promotion Strategies—Theory and Evidence from Developing Countries Commonwealth Secretariat Export Market Development Division Human Development Report 1990 for the United Nations Development Programme (UNDP) (New York and Oxford: University of Nottingham The World Bank and the Environment—First Annual Report Fiscal 1990, The World Bank (New York: The World Bank, 1990 London Environmental Economics Centre University College London The European Communities' Single Market: The Challenge of 1992 for Sub-Saharan Africa Loughborough University  相似文献   
947.
The effects of consumer education and information treatments on choice of alternative products are described. Knowledge of upholstery serviceability and flammability before and after these treatments is measured as well as simulated purchase behavior of 448 Canadian consumers. Subjects show an increase in knowledge between pre- and posttests. The choice of fire resistant upholstery differs among consumer information treatments but not among education treatments. The policy implications of these findings are discussed.  相似文献   
948.
The present study supplements Canadian consumer expenditure survey data with unique time use data to analyze family life cycle decisions regarding allocation of full income to market purchased consumption goods, home production, and leisure time. Results confirm that young children's presence causes families to increase their shares of full income allocated to home production and to decrease the shares of full income allocated to leisure. As a share of full income, expenditures for market goods steadily increase while expenditures for women's home production diminish as children age.  相似文献   
949.
The purpose of this paper is to summarize the principle points made during the course of the workshop, identify (to whatever extent is possible) a consensus position of the panel members on key issues, and to review research needs as identified by the panel. No attempt will be made to summarize each panel members' individual presentation, as such, since there was considerable overlap both in the presentation topics and in the subsequent discussions.  相似文献   
950.
Two apparatuses have been developed to characterize the entrainability of dust deposits. The minimum aerodynamic wall shear stress required for dust removal (Critical Shear Stress), measured by the first apparatus, is an indicator of the ease with which dust particles can be removed from a layer. The second apparatus measures the settling velocity distribution of dust clouds, which is an important factor controlling the extent of dispersion as well as the time period during which the entrained dust cloud can remain suspended. Testing has shown that the critical shear stress depends not only on the nature of the dust, but on the way the dust deposit is formed. Therefore, a portable version of this apparatus was developed to allow field testing of dust deposits. This methodology has also been used to evaluate the effect of oil treatment sometimes used in the grain handling industry to reduce dust emission. Simulated explosion tests have demonstrated the importance of critical shear stress on dust entrainability. A simple model calculating unsteady dust concentration in elongated structures has been developed. The model shows that flammable dust concentrations induced in a gallery by a primary explosion exist over a finite length and time period. Therefore, the probability of a secondary explosion depends not only on the dust and layer properties, but on the details of the primary explosion and of the enclosure geometry. A simple criterion for transmission of a primary explosion into an adjoining elongated structure is discussed in the paper.  相似文献   
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