Search results for "RADIOCHEMISTRY"

2019

The widespread use of 68Ga for positron emission tomography (PET) relies on the development of radiopharmaceutical precursors that can be radiolabelled and dispensed in a simple, quick, and convenient manner. The DATA (6-amino-1,4-diazapine-triacetate) scaffold represents a novel hybrid chelator architecture possessing both cyclic and acyclic character that may allow for facile access to 68Ga-labelled tracers in the clinic. We report the first bifunctional DATA chelator conjugated to [Tyr3]octreotide (TOC), a somatostatin subtype 2 receptor (SST2)-targeting vector for imaging and functional characterisation of SSTR2 expressing tumours. The radiopharmaceutical precursor, DATA-TOC, was synthe…

Determination of distribution coefficients (Kd) of various radionuclides on UTEVA resin

2016

Abstract Using radioisotope markers the distribution coefficients (Kd) of the following elements In, Sn, Sb, Te, Bi, Co, Fe, Nb, Sr, Ba, Ag, Cd, Zr, Hf and Ti were determined with different concentrations of HCl, H2SO4 and HNO3 for the extraction chromatographic resin Uranium and TEtraValent Actinides (UTEVA). This data can be used for separation of elements in complex mixtures, as well as for correct assessment of the elements chemistry with higher valences such as 3, 4, 5 or 6.

Betasympathomimetika und andere Arzneimittel zur Feuchtinhalationstherapie

2011

Die röntgenfluorimetrisehe und aktivierungsanalytische Brombestimmung in biologischem Material

1961

Die Bestimmung des Br-Gehaltes biologischen Materials ist mit Hilfe der Rontgenfluorescenzanalyse einfach und sicher moglich. Das Verfahren hat sich bei der Analyse von Seren und Muskelproben bewahrt, woruber an anderer Stelle berichtet wird.

Luminescence of polymorph crystalline and glassy SiO2, GeO2: A short review

2009

Studies of SiO 2 and GeO 2 crystals with α-quartz and rutile structures were performed during last two decades. The goal of such studies was comparison of properties with those of glassy modifications of these crystals. Luminescence of oxygen deficient centers in these glassy materials was found to resemble the luminescence of the rutile-type modification rather than α-quartz modification. In α-quartz, similar luminescence centers appear after damaging irradiation by electron beam at low temperatures (<60 K) or at ambient temperatures after gamma or neutron irradiation.

Sensitivity of alanine dosimeters with gadolinium exposed to 6 MV photons at clinical doses.

2011

In this study we analyzed the ESR signal of alanine dosimeters with gadolinium exposed to 6 MV linear accelerator photons. We observed that the addition of gadolinium brings about an improvement in the sensitivity to photons because of its high atomic number. The experimental data indicated that the addition of gadolinium increases the sensitivity of the alanine to 6 MV photons. This enhancement was better observed at high gadolinium concentrations for which the tissue equivalence is heavily reduced. However, information about the irradiation setup and of the radiation beam features allows one to correct for this difference. Monte Carlo simulations were carried out to obtain information on …

A no-carrier-added 72Se/72As isotope generator

2001

Siinznrary A no-carrier-added 72Se/72As generator has been developed for the isolation of 72As, relevant for eventual application in the syntheses of 72As-labelled radiophamaceuticals. Avoiding the addition of Se carrier and using a thennochromatographic destillation process, no-carrier-added 72As is nearly quantitatively released within 10 min. 72Se remains almost quantitatively (> 99.7%) in solution when a temperature of the separation process of 100°C is applied. Introdiiction Arsenic-72 is a positron emitting isotope with properties which are promising for eventual application in 72As-labelled radiopharmaceuticals. It has n positron emission rate of 88% and positron energies of EP+,,,,~…

Spektrochemische Untersuchungen zur geologischen Altersbestimmung nach der Rubidium-Strontium-Methode

1967

Durch die Einfuhrung rontgenfluorescenzspektroskopischer Arbeitsmethoden kann die Anwendungsmoglichkeit der Rubidium-StrontiumMethode zur geologischen Altersbestimmung wesentlich vereinfacht und verbreitert werden. Die erforderliche Isotopenanalyse ist durch Untersuchung der Hyperfeinstruktur der Strontiumlinie 4078 A mit relativ einfachen Hilfsmitteln moglich, allerdings erhoht sich dabei die Unsicherheit der Alterswerte um 10–15% bei photographischer bzw. ca. 3% bei lichtelektrischer Messung gegenuber der Verwendung eines Massenspektrometers.

Study of reliability of TLDs for the photon dose mapping in reactor neutron fields for BNCT

2008

Abstract Photon dose measurements in radiation fields having the proper characteristics for boron neutron capture therapy (BNCT) present several troubles. The thermal neutron flux is very high and produces a significant contribution to the response of most dosimeters. The consistency of photon dose measurements with CaF 2 :Tm and LiF:Mg, Ti thermoluminescent dosimeters has been studied. A method is described for obtaining the gamma dose with TLD-700 and some results are presented to test its reliability.

Intense mass-separated beams of halogens and beta-delayed neutron emission from heavy bromine isotopes

1984

Improved production yields of short-lived halogens were obtained from a ThO2 target, irradiated with 600 MeV protons, in combination with a negative surface ionization source. Mass-separated samples were studied by decay spectroscopy. Production yields of radioactive isotopes of chlorine, bromine, iodine and astatine are presented. Half-lives and relative neutron emission probabilities were measured for the heavy bromine isotopes89−92Br. Normalizing to earlier publishedPn values for89Br, the results are:89Br (4.30±0.14s,P n =13.6±0.8%),90Br (1.92±0.06s,P n =24.8±1.5%),91Br (0.53 ±0.03 s,P n =30.1 ±2.1%), and92Br (0.31 ±0.02 s,P n =34.6±2.5%). Energy spectra ofβ-delayed neutrons were measure…