An 227Ac-211Pb generator for test experiments of solution chemistry of element 114

A simple and effective method has been developed for the continuous production of the short-lived isotope Pb as a homolog of element 114 on the principle of a radionuclide generator. The method is based on the initial sorption of ²²⁷Ac or ²²³Ra on a small cation-exchange column, with subsequent “milking” of ²¹¹Pb (36.1 m) by a mixture of HCl/CH₃OH. The optimum conditions for the repeated separation of ²¹¹Pb from radionuclides strongly sorbed by the cation-exchanger (Ac, Th, Ra, Pu, TPE) have been determined. Possibilities of using the ²¹¹Pb generator for test experiments on the solution chemistry of element 114 have been shown. Advantages of aqueous alcohol HCl solutions for the isolation of ²¹¹Pb (element 114) are discussed. This revised version was published online in August 2006 with corrections to the Cover Date.     

A radionuclide generator for the production of211Pb and its daughters

²¹¹Pb and its daughters are produced in a generator system which utilizes the distillation of the intermediate daughter²¹⁹Rn from²²³Ra. The radium is precipitated as the stearate to isolate the parent while allowing the gaseous daughter to emanate. While the yield of the system is low, approximately 10%, the radionuclidic purity is extremely high. No measurable²²³Ra is found in the product.²²³Ra is separated from its parent,²²⁷Ac, by cation exchange.Deceased.Research supported in part by the Office of Health and Environmental Research, U.S. Dept. of Energy.     

Growth and decay tables for radium-225 and actinium-225

To facilitate the use of²²⁵Ra as a yield tracer in radiochemical assays of²²⁶Ra and²²⁸Ra, growth and decay tables for²²⁵Ra, and its daughter²²⁵Ac, have been computed.     

213Bi production and complexation with new picolinate containing ligands

Journal of Radioanalytical and Nuclear Chemistry -     

A high-performance X-ray system for medical device irradiation

A new concept of X-ray irradiator for low-density products on pallets is proposed. Monte Carlo simulations are applied to predict the performance of this system. The Monte Carlo predictions reveal in good agreement with experimental data obtained using products of different densities.     

A highly-efficient concentrated perovskite solar cell-thermoelectric generator tandem system

Concentrated photovoltaic (CPV) has been identified as an effective method to further enhance the efficiency of photovoltaic cells.Previous studies on CPV mainl...     

An automated microprocessor controlled system for the production of a new type of81Rb−81mKr generator

Routine production of⁸¹Rb, utilizing the⁸²Kr(p, 2n)⁸¹Rb reaction with natural krypton gas is described. Development and construction of a fully automated gas target system controlled by microprocess or is presented. A new type of⁸¹Rb–^81mKr generator based on the sorption of⁸¹Rb on ion-exchange paper was developed and investigated in operation. It may be used either for gas-phase or for liquid elution of^81mKr for different medical applications.     

A new81Rb−81mKr generator from enriched82Kr gas for medical use

Present work describes the construction and results of a new⁸¹Rb production target system using highly enriched⁸²Kr (99.95%) gas target material. The method yields a carrier-free product of highest activity and highest possible purity. It allows complete recovery of the expensive target material by freezing and avoids tedious chemical separation procedures. The remote-controlled target system has been constructed and functions extremely well.⁸¹Rb is used for the preparation of a new type of⁸¹Rb–^81mKr generator with a capacity of approximately 60 mCi for use in nuclear medical diagnostic (lung ventillation studies and angioscintigraphy).     

115Cd photonuclear production for115Cd−115mIn generator

Production of¹¹⁵Cd by means of photonuclear reaction and preparation of a^115mIn generator, based on the genetic sequence of¹¹⁵Cd^115mIn, were studied. The production rates of¹¹⁵Cd by the¹¹⁶Cd(γ, n)¹¹⁵Cd reaction were determined as a function of the maximum bremsstrahlung energies between 35 and 60 MeV. Then the parent,¹¹⁵Cd, was produced by irradiating about 0.15g of CdO with the bremsstrahlung from a 60 MeV-150 μA electron beam. After the parent in the Cd ₄ ²⁻ form was adsorbed on the Dowex 1x8 resin column, the daughter was eluted with a physiologic saline adjusted to pH 1. The generator was milked over a period of 3 days, during which time about 900 ml of eluent were allowed to flow through the column. Even after the milkings were repeated 15 times with 60 ml of the eluent, no¹¹⁵Cd was found in the^115mIn fractions (the detection limit of inactive cadmium: 0.02 μg).     

Routine production of38K for medical use

A method for a simple and fast production of³⁸K for medical use has been developed. Different target materials have been tested, yield of³⁸K and contaminants examined and chemical procedure and target system developed.     

Miniature hydride generator system for inductively coupled plasma-atomic emission spectrometry

Conclusion The detachable miniature hydride generator presented in this work gives the analytical chemist easy access to the determination of ultratrace levels of tin and germanium using a 1.2 kW-ICP spectrometer commercially available. An improvement of the detection limits of approximately 100 times those for conventional pneumatic nebulizer-ICP-AES, has been reported in this work.     

A new continuous hydride generator for ICP-AES

With the construction of a tubular hydride generator some of the technical inconveniences of the hydride generation technique are overcome. The system allows the determination of hydride forming elements and mercury with a sample uptake rate of 1 ml/min without loss of sensitivity. Due to the small volume of the reactor and the performed neutralization of the reaction mixture in the siphon the memory effect is reduced. The sodium hydroxide used for neutralization also prevents the generation of an excess of hydrogen and therefore removes its negative influence on the plasma discharge.Presented in part at the 1989 European Winter Conference on Plasma Spectrochemistry, Reutte, Austria     

A modified sorbent for99mTc generator

A modified sorbent for^99mTe generators of higher activities has been developed. The sorbent consists of two layers. The layer in which (F.P.)⁹⁹Mo is adsorbed contains alumina and silica gel mixture in the weight ratio 40∶60%. The underlaying layer contains 0.5% g of pure alumina. The performances of the columns filled with this sorbent are compared to these containing pure alumina with respect to the total elution efficiency of^99mTc and the elution efficiency ratio of subsequent elutions. Radiochemical and radionuclidic purities (⁹⁹Mo breakthrough) of eluates from both kinds of columns have also been determined and compared.     

Cyclotron production of13N-labelled ammonia for medical use

A new method for the production of¹³N-labelled ammonia is described.     

Cyclotron production of high-purity iodine-123 for medical applications

Iodine-123 is recognized today as the best radioiodine available for use in diagnostic nuclear medicine. At UC Davis, a continuous flow method was developed and has been operational since 1974 providing high-purity¹²³I made indirectly by means of the¹²⁷I(p, 5n)¹²³Xe→¹²³I reaction. Targetry and radiochemical systems are described, as well as in-progress developments for total system automation. A comparison of different quality¹²³I products is made based upon radionuclidic and dosimetry considerations. The high-purity, no-carrier-added¹²³I produced at Crocker Nuclear Laboratory is being used in many research labeling efforts in proteins, amino acids, antibiotics, fatty acids, and hormones.     

A generator for preparation of carrier-free224Ra

The construction of a dynamic generator for the separation of carrier-free²²⁴Ra is described. The mother²²⁸Th was extracted on the top of the column with di-(2-ethylhexyl)phosphoric acid on hydrophobized Chromosorb W DMCS. The function of the generator was checked during 6 months by measuring the decontamination of²²⁴Ra from²²⁸Th. Simultaneously the yield of²²⁴Ra was determined as a function of the HCl concentration and of the means of milking. The best results were obtained with 0.01–0.1M HCl; the yield was about 75% of the theoretical value, and the²²⁴Ra contained less than 0.01% of²²⁸Th.     

双环及三环核苷的合成

摘要综述了天然双环核苷、抗病毒构效研究中的双环核苷和反义寡核苷酸领域中双环及三环核苷的合成研究进展,介绍了常规官能团转化法及近年来出现的自由基环合、1,3-偶极环加成和烯烃复分解等新方法。     

The generator production of172Lu from172Hf for limited nuclear medicine research

A solvent extraction system has been developed for the separation of¹⁷²Lu from its long-lived¹⁷²Hf parent. The parent-daughter pair in equilibrium is maintained in a solution of HDEHP, and the heavy lanthanide daughter is extracted into 9M HCl. The separation factor for this generator is approximately 10⁴. The rare-earth activity so obtained is proposed for compound labelling research and animal biodistribution studies in nuclear medicine.