نتایج جستجو برای: background concentrations
تعداد نتایج: 1108431 فیلتر نتایج به سال:
[5]) show that exposure to particulate matter(or PM, which is a complex mixture of extremely small particles and liquid droplets in the air) have various short-term and long-term health effects, e.g.: 1. associations between daily average ambient PM concentrations and corresponding cardiopulmonary mortality, morbidity, and functional impairments; 2. significant association between PM10(particul...
Using a double-indicator technique, we have studied, in 10 patients undergoing aorto-coronary bypass surgery, first-pass pulmonary retention of sufentanil. Pulmonary retention was studied at three pseudo steady-state background blood concentrations of 2.8 (0.66), 6.9 (1.2) and 15.9 (2.6) ng ml-1, respectively, produced by a computer-controlled infusion. Mean first-pass pulmonary retentions at t...
Tropospheric ozone is of great importance with regard to air quality, atmospheric chemistry, and climate change. In this paper we report the first continuous record of surface ozone in the background atmosphere of South China. The data were obtained from 1994 to 2007 at a coastal site in Hong Kong, which is strongly influenced by the outflow of Asian continental air during the winter and the in...
Determining natural background concentrations of nutrients in watersheds in the developed world has been hampered by a lack of pristine sampling sites covering a range of climatic conditions and basin sizes. Using data from 63 minimally impacted U.S. Geological Survey reference basins, we developed empirical models of the background yield of total nitrogen (TN) and total phosphorus (TP) from sm...
Soils are the major terrestrial reservoir of persistent organic pollutants, and thus net volatilization from soil, when it happens, may exert a control on the atmospheric occurrence and variability of organic pollutants. Here, we report and discuss the concentrations of legacy organochlorine pesticides (OCPs) such as hexachlorobenzene (HCB), hexaclorocyclohexanes (HCH) and dichlorodiphenyltrich...
In preparation for a study of the relative oral bioavailability of polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) in soils (typically containing less than 1 ppb 2,3,7,8-tetrachlo-rodibenzo-p-dioxin [TCDD] toxic equivalents [TEQ]), the background concentrations of PCDD/Fs and selected polychlorinated biphenyls (PCBs) were measured in liver and adipose tissue from female Sprague-Da...
An experimental study investigates the oxidation-enhanced diffusion of phosphorus in silicon in both heavily doped boron and arsenic backgrounds at 900 and 1100~ This data can be modeled using the interstitial charge state levels to control the equilibrium concentration as a function of doping. The interstitials are assumed to be composed of only positive, negative, and neutral interstitial def...
p,p#-DDT (bis[p-chlorophenyl]-1,1,1-trichloroethane) is a persistent organochlorine compound that has been used worldwide as an insecticide. The authors evaluated the association of cord serum levels of DDT and its metabolite, 2,2-bis(p-chlorophenyl)-1,1-dichloroethylene (DDE), with neurodevelopment at age 4 years. Two birth cohorts in Ribera d’Ebre and Menorca (Spain) were recruited between 19...
The revised Environmental Protection Act Part 2A contaminated land Statutory Guidance (England and Wales) makes reference to 'normal' levels of contaminants in soil. The British Geological Survey has been commissioned by the United Kingdom Department for Environment, Food and Rural Affairs (Defra) to estimate contaminant levels in soil and to define what is meant by 'normal' for English soil. T...
p,p'-DDT (bis[p-chlorophenyl]-1,1,1-trichloroethane) is a persistent organochlorine compound that has been used worldwide as an insecticide. The authors evaluated the association of cord serum levels of DDT and its metabolite, 2,2-bis(p-chlorophenyl)-1,1-dichloroethylene (DDE), with neurodevelopment at age 4 years. Two birth cohorts in Ribera d'Ebre and Menorca (Spain) were recruited between 19...
نمودار تعداد نتایج جستجو در هر سال
با کلیک روی نمودار نتایج را به سال انتشار فیلتر کنید