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Abstract  

Improved radionuclide generator include a substantially insoluble salt of a radioactive parent which may be directly packed in column for subsequent elution of the daughter radionuclide. An improved 188Re generator was prepared by reacting a radioactive tungsten (188W) as parent radionuclide incorporated with aluminum chloride to obtain an insoluble radioactive aluminum tungstate matrix. The investigated matrix was characterized on the basis of the chemical composition, IR, thermal analysis and mechanical stabilities. The factors affecting the elution performance were studied such as influence of pH, molar ratio and drying temperature. From the obtained data, the molar ratio W:Al was 1.5:1 at pH = 4, the matrix dried at 105 °C for 2 h. Chromatographic and multichannel analysis has been currently used to investigate the radiochemical and radionuclidic purity respectively on eluted 188Re. An elution yield more than 80%, with radiochemical purity <98% and radionuclidic purity <99% with a 188W break through >10−4% of the column. The Al+3 and W contents value were about 2 and 3 μg/mL eluate. The obtained data approved the stability of the prepared generator and its suitability for medical application.

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. [7] A Statistical Test Suite for the Validation of Random Number Generators and Pseudorandom Number Generators for Cryptographic Applications , NIST SpecialPublication 800-22rev1a , April 2010 .

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Abstract  

Although the99Mo 99mTc radionuclide generator system has evolved as the workhorse of nuclear medicine over the past three decades, recent developments in radionuclide generator technology have provided positron emitters for PET studies, radionuclides for therapy, and ultra short-lived radionuclides for repeated clinical applications. Attention is being paid to development ofin vivo generator systems and potential use of tandem generator systems. Separation of radionuclides in a generator system exploits differences in chemical properties of the parent-daughter pair; information is presented for these generator types based on the three chemical categories of chromatography, extraction, and volatilization and sublimation methods. This review focuses on chromatography-based systems.

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– 932 . [3] Cordeiro , G. M ., Afify , A. Z ., Ortega , E. M. M ., Suzuki , A. K . and Mead , M. E ., The odd Lomax generator of distributions: Properties, estimation and applications , Journal of Computational and Applied Mathematics , 347

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Abstract  

Dependence upon pH of Ac and Th distribution coefficients between the cation exchange resin and buffer citrate solutions had been investigated; the optimal conditions are suggested for effective separation of the elements in this system. These results are in successful accordance with such conditions calculated on the basement of Ac and Th citrate complex formation constants.The generator method for225 Ac periodical separation from229 Th samples is developed.229 Th storage in solution between separations excludes the contamination of actinium final solution with radiolysis products and provides 100-% yield of this isotope and its high radiochemical purity. The parent nuclide loss after continuous use of the generator does not take place.

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Abstract  

A systematic study on the extraction of99Mo and its daughter99mTc by pure organic diluents and dinonylnaphthalinesulfonic acid (DNNS) is described. The aqueous phases used are H2SO4, HCl, KI and their binary mixture solutions. The effect of alcohols on the distribution coefficient has been investigated. As a result of the study, a simple and rapid generator is built for the production of pure99mTc from99Mo.

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Abstract  

PET with 68Ga from the TiO2- or SnO2- based 68Ge/68Ga generators is of increasing interest for PET imaging in nuclear medicine. In general, radionuclidic purity (68Ge vs. 68Ga activity) of the eluate of these generators varies between 0.01 and 0.001%. Liquid waste containing low amounts of 68Ge activity is produced by eluting the 68Ge/68Ga generators and residues from PET chemistry. Since clearance level of 68Ge activity in waste may not exceed 10 Bq/g, as stated by European Directive 96/29/EURATOM, our purpose was to reduce 68Ge activity in solution from >10 kBq/g to <10 Bq/g; which implies the solution can be discarded as regular waste. Most efficient method to reduce the 68Ge activity is by sorption of TiO2 or Fe2O3 and subsequent centrifugation. The required 10 Bq per mL level of 68Ge activity in waste was reached by Fe2O3 logarithmically, whereas with TiO2 asymptotically. The procedure with Fe2O3 eliminates ≥90% of the 68Ge activity per treatment. Eventually, to simplify the processing a recirculation system was used to investigate 68Ge activity sorption on TiO2, Fe2O3 or Zeolite. Zeolite was introduced for its high sorption at low pH, therefore 68Ge activity containing waste could directly be used without further interventions. 68Ge activity containing liquid waste at different HCl concentrations (0.05–1.0 M HCl), was recirculated at 1 mL/min. With Zeolite in the recirculation system, 68Ge activity showed highest sorption.

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Abstract  

Tin-indium generator systems were made with commercial hydrated zirconium oxide, silica gel and hydrated zirconium oxide prepared by the AMPHLETT method. The adsorption capacity of tin has been determined by both spectrophotometric analysis and gammaspectrometry. Zirconium break-through has been determined and compared with the literature values. The dependence of the adsorption capacity on the particle size has been investigated. The effect of autoclaving on the generator systems has been examined.

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Summary  

We study the pseudorandom properties of the power generator (which includes as special cases the RSA generator and the Blum--Blum--Shub generator). In order to estimate the pseudorandom measures character sums with exponential functions are used.

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