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1.
A procedure for separation of no-carrier-added 113mIn(III) radioisotope from a bulk of 110mAg has been developed. The sorption behavior of 113mIn(III) and 110mAg(I) ions in HNO3 acid solutions on different tungstocerate matrices showed high affinity of 110mAg(I) ions towards tungstocerate(IV) gel matrices compared with 113mIn(III) ions. No-carrier-added 113mIn radionuclide was separated from 110mAg on 12-tungstocerate(IV) column matrix. 11 mL 0.3M HNO3 acid solution was enough for eluting the 113mIn from the column bed. 110mAg was recovered from the column by eluting the column bed with 12 mL 2M HNO3 acid solution.  相似文献   
2.
Summary A procedure for the separation of 64,67Cu radioisotopes from irradiated natural zinc targets was developed. Production of 64,67Cu was carried out using 64,67Zn(n,p)64,67Cu reactions by fast neutron bombardment of natural zinc targets at The Second Egyptian Research Reactor (ETRR-2). The sorption behavior of 65Zn and 64,67Cu ions in HCl acid solutions showed high affinity of Cu ions towards 6-tungstocerate(IV) gel matrix compared with Zn ions. Carrier-free 64,67Cu radionuclides were separated from 65Zn on 6-tungstocerate(IV) column matrix by eluting the column with 10 ml 0.001 and 1M HCl acid solutions. The separated 64,67Cu radionuclides were of high chemical, radiochemical and radionuclidic purity.  相似文献   
3.
Journal of Radioanalytical and Nuclear Chemistry - Highly-porous nano zirconium molybdate-99Mo (Zr99Mo) gels were precipitated by a simple new radiochemical process from mixtures of...  相似文献   
4.
Summary Barium-137m radioisotope generator of the chromatographic column elution mode based on loading 1.5 g 6-tungstocerate(IV) gel matrix with ~54 kBq of fission-produced 137Cs is described. The elution performance of the generated 137mBa radionuclide was investigated as a function of chemical composition of the eluent, flow rate, elution frequency, and age of the generator system. At comparable conditions, 137mBa eluates with 0.9% NaCl-0.1M HCl eluent had higher elution yields and radionuclidic purity than with 0.1M NH4Cl-0.1M HCl eluent. The generator has been repeatedly eluted for 311 days by passing 4810 ml of the saline eluent (10 ml × 481 elution operations) at a flow rate of 3.0 ml/min. Barium-137m eluates of high and reproducible elution yields, chemical and radionuclidic purities of (≥ 99.99%) were obtained.  相似文献   
5.
Potassium nickel hexacyanoferrate(II) matrix was prepared and characterized. Purification of neutron-activation 99Mo–molybdate(VI) solutes from some residual cross-contaminant radionuclides including 134Cs, 86Rb, 124Sb, 60Co and 51Cr was carried out onto small chromatographic columns of the matrix (each of 1.0 g). Gamma-ray spectrometric analysis data showed that the purification process was not affected by either Mo(VI) concentrations (0.13 and 0.02 M Mo) in the feeding solution of 3.5 M NaNO3 at pH 9.5 or flow rates (0.2 and 5.0 mL/min) at room temperature. Molybdenum(VI) average loss onto the column matrix did not exceed 7.7 × 10?2 mmol Mo. Except for 51Cr, the matrix has very high selectivity for 134Cs, 86Rb and 124Sb with ~50% 60Co elimination. The obtained data were briefly discussed.  相似文献   
6.
In this work alumina 99Mo-molybdate (VI) gel is evaluated as a column matrix for use in the preparation of small chromatographic column type 99mTc generator. Alumina molybdate (VI) gel is prepared by dissolving inactive MoO3 with aluminum foil in 5 M NaOH solution containing 99Mo radiotracer. After complete dissolution, 0.5 H2O2 was added to the reaction mixture solution and acidified to pH 5.5 with concentrated HNO3. The formed AlMo precipitate was washed with NaNO3 solution, dried at 50 °C for 24 h and then packed in the form of a chromatographic column for elution of the generated 99mTc radionuclide with physiological saline solution (0.9 % NaCl). Greater than 86 % of the generated 99mTc activity is immediately and reproducibly eluted with passing 10 mL of the saline solution through 2.0 g of alumina 99Mo-molybdate column bed at a flow rate of about 1.0 mL/min. The high radiochemical ≥98.6 % TcO4 ?, radionuclidic ≥99.90 % 99mTc and chemical purities of the eluates satisfy the specifications for use in nuclear medicine.  相似文献   
7.
Mixed gamma-ray point sources consisting of 152Eu and 154Eu were prepared from a solution of EuCl3 containing both isotopes. Gamma-rays emitted from these isotopes were used to establish the relative efficiency curves of HPGe detector, which were converted to absolute ones using gamma-ray sources of well-known activities. Gamma-ray attenuation correction factors were taken into account. Accuracies of activity measurements of the prepared sources were checked by measuring other sources of well-known activities and confirmed by simulating the absolute efficiency curve at distance of 15?cm from the detector window using the DETEFF software. The prepared sources were then submitted to quality control tests.  相似文献   
8.
Summary Ruthenium-106 and 137Cs have been separated from thermal-neutron irradiated UO3 targets aged for ~2.5 years by distillation and surface interactions in nitrate media of controlled chemical composition. After digestion of the aged targets with their aluminum wrapper in 2M NaOH solution, nitric acid was added to complete dissolution of the formed residue. The prepared fission product solution was separated from 129I and 91.8% 106Ru by sequential distillation from 20% and 40% HNO3 solutions containing H2O2 and KMnO4, as oxidants, and by boiling for 4 and 2.5 hours, respectively. The recovery yield of 106Ru collected in 0.1M NaOH solution was ~68.2% with a radionuclidic purity of 399.99%. Thereafter, the fission product solution was brought to pH 9.5 by addition of NaOH solution to precipitate Al(OH)3, MnO2, and Na2U2O7 which selectively retained the remaining fission products leaving, mainly, 137Cs in the supernatant solution. The recovery yield of 137Cs was ≥97.3% with ~99.75% radionuclidic purity. The gamma-ray emitter contaminants which could be detected and identified in the recovered 137Cs solution, were ~0.25% 134Cs and ~1.4 . 10-3% 152,155Eu.  相似文献   
9.
A procedure for preparation of 99Mo/99mTc radioisotope generator based on low specific activity neutron activated 99Mo was developed. Aluminum molybdate(VI)-99Mo of high Mo(VI) content (~?364 mg/g Al99Mo) was prepared by mixing low specific activity molybdate(VI)-99Mo and aluminum mixture solution with isoamyl alcohol. Al99Mo gel matrix was precipitated when the pH of the mixture solution was raised to ~?5 by addition of NaOH to the mixture. Radiometric measurements indicate the strong fixation of Molybdate(VI)-99Mo species in the form of the sparingly insoluble Al99Mo gel matrix. The prepared AlMo gel matrix was physiochemically characterized. Al99Mo gel matrix was used as a base material for preparation of 99Mo/99mTc generator. The 99mTc eluted from 99Mo/99mTc radioisotope generator was found to have relatively high elution yield (84?±?2.3%), radionuclidic (≥?99.99%), radiochemical (98.1?±?0.9%) and chemical purity.  相似文献   
10.
Precipitation of radiotellurium, containing trace radioimpurities, has been carried out from sulfate media at different pH-values. The highest precipitation yield was achieved at the region of pH ~4–6. Quantitative uptake by the formed precipitate was noticed for (i) 54Mn, 110mAg and 125Sb over all the pH-range of study (pH 1.7–9.2), (ii) for 65Zn and 60Co in the regions of pH ~6–8 and pH 6–8.8, respectively, and (iii) for 134Cs in the region of pH 1.7–2.8, while its percent uptake fluctuated around 60.5 % in the region of pH 4.4–6.4. Further precipitation studies have been conducted for a mixture of 125I and radiotellurium from sulfate, nitrate and chloride media at pH-values of 6.0 and 7.5. The highest 125I recovery yield in the obtained supernatant was 95.0 ± 1.3 %, which was achieved with sulfate medium at pH 6.0 with percent uptake values of 5.0 ± 1.3, 98.9 ± 0.9 and 62.0 ± 4.6 % of 125I, 123mTe and 134Cs, respectively, and quantitative uptake of 54Mn, 110mAg, 125Sb, 60Co and 65Zn by the precipitated tellurium. Thereafter, the supernatant was further acidified with H2SO4 and boiled, after adding H2O2, for 3 h. >99 % of 125I was distilled off from the acidified supernatant. The distilled of 125I was received in 0.1 M NaOH + 1 % Na2S2O3 solution, with a radionuclidic purity of >99.99 %, radiochemical purity of >99.8 % as I? and pH ~13.  相似文献   
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