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991.
992.
Since the natural estrogens 17 beta-estradiol (E2) and estron (E1), and the synthetic estrogen 17 alpha-ethynyl estradiol (EE2) have strong endocrine disrupting effects and the tendency to persist in effluent from wastewater treatment plants, effective measures are needed to remove them from wastewater. In this research, to gain an understanding of the characteristics of estrogen decomposition by ozonation, experiments were conducted using effluent from an actual wastewater treatment plant. In this experiment, estrogen was added to effluent at a concentration of 200 ng/l and 20 ng/l before the ozonation experiments. The results showed 90% or more of estrogen concentration and estrogenic activity of E2, El and EE2 to be removed at an ozone dose of 1 mg/l. At an ozone dose of 3 mg/l, the estrogen concentration and estrogenic activity of E2, El and EE2 in the treated water fell below the detection limit. The removal rate was not influenced by the kind of estrogen. No generation of byproducts with estrogenic activity was observed. The authors conclude that estrogen in secondary treated wastewater can be almost entirely removed at the practical ozone dose rate applied for the purpose of disinfection, which is up to about 5 mg/l.  相似文献   
993.
The current work presents the procedure of designing and carrying out measurements of radiation emission from an air-traffic surveillance radar. The system requirements are first given, and then the equipment used is described. The steps to determine the operating characteristics of the radar are specified in detail. The necessary methods for manual power measurements and calculations are next explained. Since the final measurement system was fully automated, its main features (topology, protocol of operation) are also given. Finally, some measurement results taken during the initial phase of system operation are presented and discussed.  相似文献   
994.
The phase diagrams of ternary liquid systems tetradecane-n-octanol (or cyclohexanone)-lanthanide(III) nitrate solvates with tri-n-butyl phosphate [Ln(NO3)3(TBP)3, Ln = La, Ce, Pr, or Sm] at T = 298.15 K were studied. These diagrams contain areas of homogeneous solutions and an area of separation into two liquid phases (I, II). Phases I and II are enriched in tetradecane and Ln(NO3)3(TBP)3, respectively. n-Octanol and cyclohexanone mainly pass into phase II.  相似文献   
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Studied the effects of variations in base rate (BR) information and temporal context on predictions of violence and hindsight bias (HB). 270 undergraduates estimated the likelihood of violent offenders committing another violent offense based upon fictitious case history information. Ss were given 1 of 2 population BRs of the likelihood of reoffending (30% or 70%) and a recidivism estimation question that was phrased either predictively, predictively with a given outcome of either recidivism or no recidivism, or postdictively. Although different offenders were perceived as differentially likely to reoffend, estimated likelihood of recidivism was affected by neither BR nor temporal phrasing of the estimation task. A 2nd study of 182 undergraduates, using shorter case histories, also found no BR effect. HB effects were weak and inconsistent in both studies. (French abstract) (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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