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91.
92.
Analysis for tetra- through octachloro-PCDDs and PCDFs was completed for 46 tissue samples prepared from the U.S. Environmental Protection Agency (EPA) National Human Adipose Tissue Survey (NHATS). The samples were prepared as composites from over 900 specimens to represent the nine U.S. census divisions and three age groups (0–14, 15–44, and 45 plus years). The data demonstrate that PCDDs and PCDFs are prevalent in the general U.S. population and that differences exist with age.  相似文献   
93.
94.
Alloxan-induced diabetic rats were treated with multiple herbal preparation besides a control group receiving distilled water. The levels of glucose and alkaline phosphatase (ALP) increased abnormally in the alloxan treated group and the same were normalized upon treatment with the herbal preparation. The levels of blood urea nitrogen (BUN), alanine aminotransferase (ALT), protein and albumin in all groups remained unaltered. However, weekly body weight gain which got significantly altered in the alloxan-treated group was normalized by treatment with the herbal preparation. On the whole, a profound hypoglycemic effect was observed by the multiple herbal treatment in the diabetic rats.  相似文献   
95.
Guided group discussion ( [Lewin et?al., 1952] , [Werner, 2003] and [Werner and Adams, 2001] ) was used to persuade groups to replace their toxic home and garden chemicals with nontoxic alternatives. We hypothesized that discussion would allow participants to hear others endorse the new information, and this normative information would facilitate persuasion. Approximately two months after the group discussion, we obtained questionnaires from the organizer of the meeting and a member of the group who had missed the meeting because of another obligation (i.e., not because of disinterest in the topic). Most organizers were female and analyses were limited to females. This quasi-experimental matched control group design indicated that those who attended the meeting were more favorable towards using nontoxics and more interested in sharing leftover toxic products with friends (instead of discarding them). Path and mediation analyses showed that the organizer’s evaluation of the meeting predicted her final attitude, and perceptions that the group endorsed the material (perceived group norm) partially mediated this relationship. A second mediation analysis showed that evaluation of the meeting predicted intention to share leftover toxics and this relationship was fully mediated by the organizer’s impression that the group would also share leftovers. The results support the idea that persuasion is based both on individual evaluation and normative influence, especially when people are not confident others will accept the behavior, such as sharing leftover toxic products.  相似文献   
96.
During the past several years, an increasing body of evidence and opinion has formed concerning the relationships between advancements in environmental, health, and safety (EH&S) management and the financial performance of the organization. In recent work,1 we have described a new theoretical model linking improvements in environmental management systems and environmental performance to corporate risk, stock volatility, and market value, as well as an empirical evaluation that validated our model. A number of other studies2 have documented changes in the market value of corporate equity as a function of environmental accidents, incidents, and (conversely) accomplishments. These are in addition to the numerous examples presented in the literature and at EH&S conferences and symposia that suggest that concerted efforts to reduce the organization's environmental “footprint” can yield cost savings, increased market share, reduced time to market, and perhaps other financial benefits. Some have gone so far as to proclaim that a new era has begun, in which environment-friendly corporations will increasingly be recognized and rewarded by financial market participants, and organizations that lag behind will be severely penalized.3 This article documents a new survey undertaken to identify important environmental factors, if any, investors employ in evaluating the quality and worth of equity and debt financing instruments.  相似文献   
97.
The assumption of demographic closure in the analysis of capture-recapture data under closed-population models is of fundamental importance. Yet, little progress has been made in the development of omnibus tests of the closure assumption. We present a closure test for time-specific data that, in principle, tests the null hypothesis of closed-population model M t against the open-population Jolly-Seber model as a specific alternative. This test is chi-square, and can be decomposed into informative components that can be interpreted to determine the nature of closure violations. The test is most sensitive to permanent emigration and least sensitive to temporary emigration, and is of intermediate sensitivity to permanent or temporary immigration. This test is a versatile tool for testing the assumption of demographic closure in the analysis of capture-recapture data.  相似文献   
98.
Multivariate Analysis of the Hong Kong Victoria Harbour Water Quality Data   总被引:5,自引:0,他引:5  
Two multivariate techniques (principal components analysis and cluster analysis) are used to analyse Hong Kong Victoria Harbour water quality data. Results show that the sampling stations can be divided into four main groups, which is consistent with the tripartite structure obtained from an environmental approach. Moreover, it is found that the groups produced can be interpreted based on two main features of the data: nutrient level and the algae-faecal pollution.  相似文献   
99.
The U.S. Environmental Protection Agency (EPA), in cooperation with E.I. DuPont de Nemours & Company, Inc. (DuPont) and the Oberlin Filter Company (Oberlin), undertook a field demonstration project to evaluate microfiltration technology for removal of zinc and suspended solids from wastewater. The microfiltration system utilized DuPont's Tyvek T-980 membrane filter media in conjunction with the Oberlin automatic pressure filter. The project was undertaken at the Palmerton Zinc Superfund site in April 1990 to verify the ability of the technology to remove dissolved zinc from the site's shallow groundwater. Pretreatment of the groundwater with lime for pH adjustment to precipitate dissolved zinc and other metals was included as part of the technology demonstration program. Analysis of the treated filtrate indicated that the system removed precipitated zinc and other suspended solids at an efficiency greater than 99.9 percent. The filter cake produced during the study passed both the Extraction Procedure (EP) Toxicity and the Toxicity Characteristic Leaching Procedure (TCLP) tests.  相似文献   
100.
A novel aspirative wet scrubber system makes use of condensation forces to enhance fine particulate collection. A pressure gain of 2 to 4 inches, W.C. is generated by the system and total water pump power requirements for multistage systems are 2 horsepower per thousand scfm. of gas throughput. No fans or blowers are utilized. When scrubbing hot combustion products carrying 0.1 to 6.0 micron metal oxide particles from a kiln, total collection efficiency was 99.4%. Collection of fly ash, in the particle size range 0.1 to 10 microns, has been measured at 99.5% efficiency.  相似文献   
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