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[en] The Old Rifle Site is a former vanadium and uranium ore-processing facility located adjacent to the Colorado River and approximately 0.3 miles east of the city of Rifle, CO. The former processing facilities have been removed and the site uranium mill tailings are interned at a disposal cell north of the city of Rifle. However, some low level remnant uranium contamination still exists at the Old Rifle site. In 2002, the United States Nuclear Regulatory Commission (US NRC) concurred with United States Department of Energy (US DOE) on a groundwater compliance strategy of natural flushing with institutional controls to decrease contaminant concentrations in the aquifer. In addition to active monitoring of contaminant concentrations, the site is also used for DOE Legacy Management (LM) and other DOE-funded small-scale field tests of remediation technologies. The purpose of this laboratory scale study was to evaluate the effectiveness of a hydroxyapatite (Ca10(PO4)6(OH)2) permeable reactive barrier and source area treatment in Old Rifle sediments. Phosphate treatment impact was evaluated by comparing uranium leaching and surface phase changes in untreated to PO4-treated sediments. The impact of the amount of phosphate precipitation in the sediment on uranium mobility was evaluated with three different phosphate loadings. A range of flow velocity and uranium concentration conditions (i.e., uranium flux through the phosphate-treated sediment) was also evaluated to quantify the uranium uptake mass and rate by the phosphate precipitate.
[en] Two levels metalloid impurity elements reference material in uranium concentrate were developed. The reference materials can be used for the trace measuring value and its transfer of metalloid impurity elements, manufacturing environment of reference materials was in accordance with the technical specification of national class A standard substance. (authors)
[en] In this project we have researched and evaluated the separation possibility of uranium ore in Palua area. Although scale and expenses of the project are limited, we have carried out this project during a year and had some reliable results. Uranium ore in Palua area which has concentrate of 440 ppm was separated into two main ingredients containing uranium concentrate more than 550 ppm and less than 190 ppm. (author)
[en] For the sake of safety it would be desirable to store and transport the ready-for-use liquid formulation (diagnostics and therapeutics) of radiolabelled peptides. The use of ethanol, in combination with a mixture of gentisic- and ascorbic acid, has superior effects on stabilizing radiolabelled somatostatin analogs. As a consequence, 111In- and 177Lu-labelled somatostatin analogs can be stored and transported in a single-vial ready-for-use liquid formulation up to 7 days after radiolabelling. - Highlights: • Optimal quencher combination: ascorbic- and gentisic acid and ethanol. • Used quencher concentrations had no effect on pharmacokinetics. • Purging the reaction mixture with N2 after radiolabelling resulted in 10% higher RCP. • Quencher mixture stabilize 111In- and 177Lu-labelled SS-analogs during 7 days. • Enables to store and transport 111In- and 177Lu-labelled SS-analogs in a single-vial
[en] A analysis method for determination of sulphuric acid radical in diuranate by barium sulfate nephelometery was studied. The experimental results show that the linear correlation coefficient (r) > 0.997 when concentration of sulphuric acid radical was in the range of 16 to 40 μg/mL. The detection limit of the method was 0.4% when sample quantity was 0.5 g, and the recovery was in the range of 90.7% to 105%. RSD was 2.8% when concentration of sulphuric acid radical was 5.72%. 0.4 mg of fluorin and 10 mg of calcium did not interfere with determination of sulphuric acid radical. (authors)
[en] Concentration of [18F]fluoride has been mentioned in literature, however, reports have lacked details about system designs, operation, and performance. Here, we describe in detail a compact, fast, fully-automated concentration system based on a micro-sized strong anion exchange cartridge. The concentration of radionuclides enables scaled-up microfluidic synthesis. Our system can also be used to provide highly concentrated [18F]fluoride with minimal water content. We demonstrate how the concentrator can produce varying concentrations of [18F]fluoride for the macroscale synthesis of N-boc-5-[18F]fluoroindole without an azeotropic drying process, while enabling high starting radioactivity. By appropriate choice of solid-phase resin, flow conditions, and eluent solution, we believe this approach can be extended beyond [18F]fluoride to other radionuclides.
[en] Effects of gamma radiation combined with cinnamon oil on quality of Northern Snakehead fish fillets were observed during storage at 4 °C. Fish fillets were treated with 1–5 kGy gamma radiation, 0.05–0.5% cinnamon oil or the combination of radiation and cinnamon oil. The antimicrobial activity increased with radiation dose and cinnamon oil concentration. During storage, the combination of 1 kGy radiation and 0.5% cinnamon oil displayed better inhibiting activities on aerobic plate counts, total volatile basic nitrogen, thiobarbituric acid reaction substances than 1 kGy radiation or 0.5% cinnamon oil used alone. Moreover, the combination could arrive at the similar inhibiting activities of cinnamon oil with higher concentration of 0.5% or radiation with higher dose of 5 kGy. Thus, the combination could decrease the radiation dose and cinnamon oil concentration without decreasing the effect of them on maintaining fish quality. - Highlights: • Radiation combined with cinnamon can efficiently maintain fish quality. • TBARS were lower in radiated samples than non-radiated samples. • Index of pH is not useful for monitoring Northern Snakehead quality.
[en] Highlights: • A simple, low-cost, and sensitive liposome-based colorimetric aptasensor has been developed to detect OTA. • The strategy combines advantages of the signal amplification of liposome and the high specificity and low cost of aptamer. • The signal amplification via HRP-encapsulated lipsomes can be achieved in one step without additional surfactant. • The proposed colorimetric aptasensor has been applied to detect OTA concentration in corn samples with satisfied result. - Abstract: A simple, low-cost, and sensitive liposome-based colorimetric aptasensor has been developed to detect ochratoxin A (OTA). Specifically, a dumbbell-shaped probe was designed, including magnetic beads (MBs), double-stranded DNA (dsDNA), and enzyme-encapsulated liposome. The dsDNA formed by the hybridization between OTA aptamer and its complementary probe. And the dsDNA was used to contact the MBs and the enzyme-encapsulated liposome. In the presence of OTA, the aptamer preferred to combine with OTA to form G-quadruplex, resulting in the release of the detection probe and the enzyme-encapsulated liposome. Each liposome contained a large amount of HRP. Thus, when the liposome was lysed by adding the mixed solution of 3,3′,5,5′-tetramethylbenzidine (TMB) and H2O2, a large number of HRP were released. HRP could catalyze the H2O2-mediated oxidation of TMB and hence resulted in the color change from colorless to blue with the OTA concentration varying, and this variation can be observed by naked eyes easily. The result showed that the absorption intensity at 652 nm enhanced with the increase of OTA concentration ranging from 0.05 to 2.0 ng mL−1, and the limit of detection was calculated to be 0.023 ng mL−1 (S/N = 3). The developed colorimetric aptasensor has been applied to detect OTA concentration in corn samples with satisfied results.