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This study of a sample of home gardeners indicates that rules of thumb, or heuristics, are used to select between chemical pesticides and nonchemical alternatives. Such rules of thumb serve to simplify otherwise complicated choice decisions. Heuristics commonly used to choose pesticides include how safe, effective, efficacious, and economical they are, whereas for alternative products consumers more often take into account convenience, efficiency, competency, and handiness. Generally, in an overall ranking of 24 individual choice attributes, pesticies rank low on these attributes where alternatives rank high and vice versa. Gender, age, and years using pesticides are significantly correlated with pesticide selection.  相似文献   
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The manner in which specific chemicals are used is studied in order to identify plausible release scenarios and the probability of their occurrence.  相似文献   
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CHETAH, which stands for the Chemical Thermodynamic and Energy Release Program, was introduced in 1974. Since then, the CHETAH program has been widely used in the chemical industry for hazard evaluation. Although its chief aim is to predict deflagration/detonation potential from molecular structure, it can also be used to estimate heats of reaction, heat capacities, and entropies. One of the limitations of the original program was its rigid, punched card oriented format for data input and the lack of an overall hazard rating derived from the several hazard criteria. A new release of this program alleviates these shortcomings and includes other improvements. The main features of the new release are: 1) a totally interactive front end, 2) an interpreter subroutine which uses sophisticated pattern recognition techniques to combine the four hazard criteria into an overall hazard rating, 3) recognition of certain atomic groupings which are known to be sensitive, 4) correct handling of the symmetry number, and 5) an updated data bank. One of the most important features of this release is its availability in an IBM PC compatible version, making the program accessible to more users.  相似文献   
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Despite their growing economic power, children's acquisition and use of money rarely has been investigated in academic research, although it has been a frequent topic in the media. This study (1) describes sources and uses of money children (age 10–15) receive; and (2) investigates the association of children's uses of money with their age, gender, family structure, and sources of money. The sources of money are associated with children's uses of it, but age, gender, and family situation do not relate to the way they use money. Consumer education should focus on the sources of children's money in relation to the way they use it.  相似文献   
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