نتایج جستجو برای: total uranium
تعداد نتایج: 808576 فیلتر نتایج به سال:
abstract uranium as a natural radioactive heavy metal widely disperses throughout the earth's crust. in many cases, the natural abundance has been re-distributed due to anthropogenic activities, resulting in radionuclide contamination in groundwater and surface soil. uranium through the plant uptake can enter the chain. the degree of speciation of radio nuclides in soils in areas with differing...
A solid chelating material, 1-(2-pyridy1azo)-2-naphthol (PAN) supported on naphthalene provides a rapid and highly selective means of preconcentration of uranium from aqueous solution. Uranium is quantitatively retained on this adsorbent in the pH range 9.8-10.7 with a flow rate of 1 ml min . The metal complex was desorbed with 10 ml of 2 M hydrochloric acid and uranium is determined by d...
Background: Measurement of back ground concentration of uranium in drinking water is very important for many reasons, specially, for human health. The uranium concentration in drinking water in many counties is a matter of concern for clinical and radioactive poisoning. Materials and Methods: The uranium concentration in drinking water is determined using laser flourimatric uranium analyzer. Fo...
Uranium is an alpha-emitting, radioactive, heavy metal that occurs naturally in nearly all rocks and soils. Twenty-two isotopic forms of uranium have been identified, mainly associated with nuclear reactor operations or high-energy physics experiments; the most prevalent isotopes found in the environment are the three naturally-occurring isotopes: U, U, and U. Most uranium isotopes undergo deca...
The study deals with testing of versions 4.0 and 4.2 of the Multi-Group Analysis for Uranium (MGAU) software. MGAU is used for determining uranium isotopic composition by means of gamma spectrometry. The aim of the study was to determine the optimal measurement conditions needed to get the MGAU results as accurate as possible. The optimal number of total counts and the optimal count rate were d...
The paper reports recent observations among Czech uranium miners. The study includes two groups of underground miners exposed in periods 1948-63 and 1968-88. A total of 9960 workers have been followed to the end of 1999 representing 267 thousands person-years. By the end of 1999, a total of 29 cases of leukaemia were observed. The standardized mortality ratio is 1.31, 90%CI: 0.88-1.88. In relat...
The purpose of this work is to present an outline of the metabolic pathways of uranium isotopes and compounds, medical consequences of uranium poisoning, and an evaluation of the therapeutic alternatives in uranium internal contamination. The chemical toxicity of uranium has been recognized for more than two centuries. Animal experiments and human studies are conclusive about metabolic adverse ...
The fission rate during JCO criticality accident is estimated from fission-product (FP) radioactivities in a uranium solution sample taken from the preparation basin 20 days after the accident. The FP radioactivity data are taken from a report by JAERI released in the Accident Investigation Committee. The total fission number is found quite dependent on the FP radioactivities and estimated to b...
Groundwater within Area 3 of the U.S. Department of Energy (DOE) Environmental Remediation Sciences Program (ERSP) Field Research Center at Oak Ridge, TN (ORFRC) contains up to 135 microM uranium as U(VI). Through a series of experiments at a pilot scale test facility, we explored the lower limits of groundwater U(VI) that can be achieved by in-situ biostimulation and the effects of dissolved o...
Natural uranium is comprised of three radioactive isotopes: 238 U, 235 U, and 234 U. Depleted uranium (DU) is a byproduct of the processes for the enrichment of the naturally occurring 235 U isotope. The world wide stock pile contains some 11⁄2 million tons of depleted uranium. Some of it has been used to dilute weapons grade uranium (~90% 235 U) down to reactor grade uranium (~5% 235 U), and s...
نمودار تعداد نتایج جستجو در هر سال
با کلیک روی نمودار نتایج را به سال انتشار فیلتر کنید