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131.
132.
In this article, Rohm & Haas' Responsible Care® implementation strategy and management system verification (MSV) experiences are detailed. Recommendations on how to strengthen the verification process are provided. 相似文献
133.
134.
Howard M. Prichard Thomas F. Gesell Charles T. Hess Conrad V. Weiffenbach Philip Nyberg 《Environment international》1982,8(1-6)
Radon concentrations were measured in several locations in each of approximately 100 dwellings in central Maine and in Houston, TX. Integrated samples were taken during the heating (or cooling) seasons with commercially available passive alpha track devices, while grab samples were taken at the time of integrated sampler deployment. It was found that both indoor and outdoor measurements in both areas were distributed log normally, and that the geometric mean of indoor measurements in Maine was three times higher than that of corresponding measurements in the Houston area. It was also noted that the mean of the indoor grab sample measurements was not significantly different from the mean of the indoor integrated measurements, and that the degree of correlation between the grab samples and a given indoor integrated sample was nearly as good as between integrated samples taken at different living area locations. 相似文献
135.
D. F. Soule M. Oguri F. Shahrokhi N. L. Jones L. A. Sharver M. S. Connor R. W. Howarth R. W. Yeung G. C. Christodoulou J. J. Connor B. R. Pearce D. A. Rice R. D. Anderson J. W. Anderson N. V. Alisov E. B. Valev A. V. Doncheva V. N. Kalutskov Paul E. Lydolph Philip P. Micklin N. T. Kuznetsov 《Environmental management》1977,1(6):549-555
136.
Bottleneck(s) or Metapopulation in Cheetahs 总被引:2,自引:0,他引:2
Philip W. Hedrick 《Conservation biology》1996,10(3):897-899
137.
D. Philip Whitfield 《Behavioral ecology and sociobiology》1990,27(4):247-254
Summary The mating system of the red-necked phalarope Phalaropus lobatus is usually classed as polyandrous, but studies show that the majority of females are monogamous. Polyandry appears to be constrained because later arriving males do not usually nest with females that have already laid a clutch that season (C1-females), despite the sexual receptiveness of these females. Rather they nest with females that have not previously laid a clutch that season (C0-females). Five potential explanations of this constraint on polyandry were tested. Two hypotheses, invoking female-female competition, were not supported as female agonistic success appeared to be unrelated to priority of access to males, and there was no apparent difference between C0- and C1-females in their ability to find unpaired males. Two hypotheses suggest that C0-females are preferred by males either because they can initiate a clutch more rapidly or because they lay larger eggs. Neither hypothesis was supported by the available data. The data upheld a third male choice hypothesis that C1-females are discriminated against because they have copulated previously with another male and this may compromise paternity. Secondary males copulated and attempted to copulate more often when paired with C1-females, suggesting that sperm competition was greater and confidence of paternity was lower. Corroborative evidence of active male choice showed that males were more aggressive towards associating C1-females than towards C0-females, although how males discriminated between the two classes of females was not determined. 相似文献
138.
Douglas W. Kuehl Philip M. Cook Allan R. Batterman Douglas B. Lothenbach Brian C. Butterworth Darcy L. Johnson 《Chemosphere》1985,14(5):427-437
The bioavailability of 2,3,7,8-TCDD from municipal incinerator fly ash to freshwater fish was determined. It was observed that carp exposed to fly ash containing all 22 TCDD isomers, or the solvent extract of the fly ash, retain only 2,3,7,8-TCDD. Exposures with fly ash appears to follow a dose response relationship for bioconcentration, however, the bioavailability of 2,3,7,8-TCDD was not directly related to the level of 2,3,7,8-TCDD in fly ash for two fly ash samples studied. 相似文献
139.
Because the particulate organic carbon (OC) concentrations reported in U.S. Environment Protection Agency Speciation Trends Network (STN) data were not blank corrected, the OC blank concentrations were estimated using the intercept in particulate matter < or = 2.5 microm in aerodynamic diameter (PM2.5) regression against OC concentrations. The estimated OC blank concentrations ranged from 1 to 2.4 microg/m3 showing higher values in urban areas for the 13 monitoring sites in the northeastern United States. In the STN data, several different samplers and analyzers are used, and various instruments show different method detection limit (MDL) values, as well as errors. A comprehensive set of error structures that would be used for numerous source apportionment studies of STN data was estimated by comparing a limited set of measured concentrations and their associated uncertainties. To examine the estimated error structures and investigate the appropriate MDL values, PM2.5 samples collected at a STN site in Burlington, VT, were analyzed through the application of the positive matrix factorization. A total of 323 samples that were collected between December 2000 and December 2003 and 49 species based on several variable selection criteria were used, and eight sources were successfully identified in this study with the estimated error structures and min values among different MDL values from the five instruments: secondary sulfate aerosol (41%), secondary nitrate aerosol (20%), airborne soil (15%), gasoline vehicle emissions (7%), diesel emissions (7%), aged sea salt (4%), copper smelting (3%), and ferrous smelting (2%). Time series plots of contributions from airborne soil indicate that the highly elevated impacts from this source were likely caused primarily by dust storms. 相似文献
140.
Freshwater fish, Cyprinus carpio were exposed to sublethal concentration (1.2 microg l(-1)) of cypermethrin for 6, 12, 24 and 48 h to analyze various parameters of protein metabolism in functionally different tissues. Total, structural and soluble proteins showed decrement; where as free amino acids and the activities of protease, aspartate aminotransferase and alanine aminotransferase significantly increased in cypermethrin exposed fish. Interestingly, ammonia content decreased but urea and glutamine increased at all periods of exposure. It was also observed that alterations steadily increased with the period of exposure and exhibited tissue specificity. Thus variation in the protein metabolism of the fish exposed to cypermethrin indicates its toxic effect on the cellular metabolism thereby leading to impaired protein synthetic machinery. 相似文献