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Deuteron-induced nuclear reactions for the generation of 103 Pd were investigated using the stacked-foil activation technique on rhodium targets at deuteron energies up to E d =33MeV. The excitation functions of the reactions 103 Rh(d,xn) 101,103 Pd, 103 Rh(d,x) 100g,cum,101m,g,102m,g Rh and 103 Rh(d,2p) 103 Ru have been measured, and the Thick-Target Yield for 103 Pd has been calculated., (Copyright © 2017 Elsevier Inc. All rights reserved.)

Deuteron-induced nuclear reactions for generation of no-carrier-added (NCA) Lu isotopes were investigated using the stacked-foil activation technique on natural Yb targets at energies up to Ed=18.18MeV. The decay curve of ¹⁷⁷Yb, the growth curve of the cumulative (direct and indirect) and the direct production of (177g)Lu were determined. The analysis of these curves conducts to the evidence that the predominant route for the production of (177g)Lu is the indirect reaction ¹⁷⁶Yb(d,p)¹⁷⁷Yb, which decays to (177g)Lu. In the spectra acquired one year from the EOB the γ lines of (177m)Lu are not evident. A comparison between the calculated activity of (177g)Lu produced with a cyclotron and with a nuclear reactor is given., (Copyright © 2014 Elsevier Inc. All rights reserved.)

Deuteron-induced nuclear reactions for generation of no-carrier-added Lu radionuclides were investigated using the stacked-foil activation technique on natural Yb targets at energies up to E(d)=18.18 MeV. Excitation functions of the reactions (nat)Yb(d,xn)(169,170,171,172,173,174g,174m,176m,177g)Lu and (nat)Yb(d,pxn)(169,175,177)Yb have been measured, among them three ((169)Lu, (174m)Lu and (176m)Lu) are reported for the first time. The upper limit of the contamination from the long-lived metastable level (177m)Lu was evaluated too. Thick-target yields for all investigated radionuclides are calculated., (Copyright © 2010 Elsevier Ltd. All rights reserved.)

Very high specific activity (A(S)) (186g)Re could be produced by either proton or deuteron cyclotron irradiation on highly enriched (186)W target in no-carrier-added (NCA) form, leading to a A(S) very close to the theoretical carrier free (CF) value of 6.88GBqmicrog(-1). Thick target yields (TTYs), obtained irradiating both thick metal W targets of natural isotopic composition and highly enriched pressed powdered (186)W targets, were measured at different particles energies taking into account high accuracy and precision on both yield and beam energy. The measurement of radionuclidic purity of (186g)Re obtained activating highly enriched (186)W by both p and d beams were also carried out and accurately compared. The excitation function as thin-target yields (tty, i.e. proportional to the reaction cross-sections) and the integrated TTYs for all Re (A=181, 182, 183, 184, 186 and their metastable levels), W and Ta co-produced radionuclides will be presented elsewhere in deep details.

In this paper are presented the production methods for very "high specific activity" radionuclides (HSA-RN) of vanadium, manganese and thallium which have been developed in our laboratories for labelling different chemical forms of these elements present in the echo-systems in ultra-trace amounts, for metallo-toxicological and bio-kinetic studies. Use was made of both cyclotron and thermal nuclear reactor. If the nuclear reaction product has atomic number different from irradiated target, it is possible separating the radioactive nuclide from irradiated target, without addition of isotopic carrier. This kind of radionuclide is named No Carrier Added, NCA, and his specific activity, As is very high and can reach values close to the theoretical Carrier Free one, CF. The experimental determination of specific activity, chemical and radiochemical purities is mandatory for all these kinds of applications.

There is much interest in understanding the biokinetics of zirconium in humans due to the potential radiological risk represented by the radionuclide 95Zr and by its daughter 95Nb. Despite the significance of zirconium, few data are available on the actual biokinetics of zirconium in humans. Accordingly the biokinetic model currently recommended by ICRP for this element is based mainly on data from animal experiments. In this study, the use of the stable isotopes 90Zr and 96Zr as tracers has enabled the conduct of 6 biokinetic investigations in 3 healthy volunteers. These studies have provided new valuable information about intestinal absorption and kinetics in blood plasma of zirconium and have been used for the set-up of a more realistic compartmental model with possible applications for dosimetric purposes.

Very High Specific Activity RadioNuclides, HSARN, are a powerful tool to label a wide variety of chemical elements and compounds present in the biosphere in ultra-trace amounts. Medium and high Z radionuclides, can be produced by irradiation in light-ions accelerator and sometimes nuclear reactor. If the nuclear reaction product has atomic number different from irradiated target, it is possible separating the radioactive nuclide from irradiated target, without addition of isotopic carrier. These kinds of radionuclides are named No Carrier Added, NCA, and their specific activity is very high and can reach values close to the theoretical Carrier Free one. The true specific activity must be determined by use of very sensitive radioanalytical techniques. If a low isotopic dilution factor is obtained, these radiotracers are used to label inorganic species and complexes of elements, which are presently introduced into the echo-systems by human activities. New production methods for NCA Pt, Ir, Au, Cu and Ga radiotracers are presented, with some details on radiochemistry and quality controls.

I, Cs and Cs were observed in environmental samples in Milano (40°N), Italy and Thessaloniki (45°N), Greece, soon after the nuclear accident in Fukushima, Japan. The radionuclide concentrations were determined and studied as a function of time. In Thessaloniki the I in air was observed for the first time on March 24, 2011. In Milano, the first evidence of Fukushima fallout has been confirmed with I and Cs measured in wet precipitation collected 2 days later. The maximum I activity concentration in air of 467 ± 25 μBq m, observed in Milano on April 3-4, 2011, was almost similar to the highest value of 497 ± 53 μBq m observed in Thessaloniki. The Cs/Cs activity ratio values in air were around 1 in both regions. Soil, grass and milk samples were contaminated with I and Cs at a low level. Finally, a dose assessment for these two areas showed clearly that the detected activities in all environmental samples were far below levels of concern. [ABSTRACT FROM AUTHOR]

Thanks to its favorable decay characteristics, 177gLu is finding several applications in nuclear medicine, especially for palliative metabolic radiotherapy of cancer and radioimunotherapy. 177gLu is produced in thermal nuclear reactor either by direct neutron capture 176Lu(n,γ)177(m+g)Lu on either natural or enriched 176Lu target, or by reaction on enriched 176Yb target followed by negatron decay. The latter method does produce a high radionuclidic purity and high specific activity radionuclide in no-carrier-added form, since 177Yb decays solely to the ground state 177gLu. Conversely, the first method does produce a low specific activity 177gLu in carrier-added form,1 contaminated by the long-lived radioisotopic impurity 177mLu. The accurate determination of radionuclidic purity and half-life of 177gLu carried out by HPGe and LSCS is presented in some details. [ABSTRACT FROM AUTHOR]

The limited number of radionuclides emitting alpha-particles and their limited availability is discussed. A new alpha-emitter 230U ( T 1/2 = 20.8 d, 100% a) is suggested and its preparation from thorium target bombarded by accelerated protons (via initial formation of 230Pa ( T 1/2 = 17.4 d, 8.4% decay to 230U)), or 4He is discussed. The Empire II model was used to calculate the excitation functions for the different products from bombardment of Th by protons. The calculated thick target yield for 230Pa is 0.6 mCi/mA . h, leading to about 24 mCi/mA . h of 230U or about 150 mCi/mA . h in the case of alpha-bombardment. [ABSTRACT FROM AUTHOR]

Many labeled compounds are used as radiopharmaceuticals (RP), for emission imaging and metabolic radiotherapy and contain as labeling agentsγ,β-,β+, monochromatic e-andα emitting radionuclides (RN). These labeled compounds very often contain unexpected radionuclidic impurities. Some long-lived isotopic and non-isotopic impurities lead to undesirable radiation doses to the patient and his relatives, as well as to medical/paramedical personnel, other than the general population, due to rad-waste of contaminated specimen and excretion of biological fluids. Use was made of liquid scintillation counting/spectrometry (LSCS) for the detection of tiny amounts of charged particle emitting impurities in RPs labeled with64Cu,67Ga,90Y,90Sr/90Y,123I,153Sm,177Lu and201Tl. [ABSTRACT FROM AUTHOR]

Radionuclides of very high specific activity AS(t) have great relevance for applications in the life sciences. Updated definitions of AS are given. The real AS(t) must be measured by analytical and radioanalytical techniques. No-carrier-added (NCA) radionuclides have AS(NCA) sometimes close to the carrier-free (CF) value AS(CF). The accurate knowledge of excitation functions of nuclear reactions vs. ion beam energy is mandatory to maximize AS(NCA); the minimization of isotopic dilution factor IDF(t) has been achieved too. A range of accelerator production and radioanalytical QC methods for AS(NCA) optimization and determination is presented. [ABSTRACT FROM AUTHOR]

The activity size distributions of the natural radionuclide tracer 7Be in different size fractions (<0.4 μm, 0.4–0.7 μm, 0.7–1.1 μm, 1.1–2.1 μm, 2.1–3.1 μm, 3.1–4.2 μm, 4.2–5.8 μm, 5.8–9.0 μm > 9.0 μm) were determined at four different site places in Northern Italy during the four seasons of the year 2011. One cascade impactor operated at the LASA-station considered the reference station and the other used for simultaneous measurements at the three other sites. Three sets of independent samples were collected during every season of the year 2011. The initial activity distribution inverted into smooth size distribution. The model parameters successfully defined to obtain the best fit-curve and two or three modes were resolved, with the predominant fit at the accumulation range. The lowest Activity Median Aerodynamic Diameter (AMAD) values were observed during summer. The AMAD values were anticorrelated with 7Be activities, while they were correlated with Relative Humidity. Similar AMAD values in suburban and urban regions were observed during all periods of the year. AMAD values of 7Be aerosol particles in areas with poor air quality were greater than those at the less polluted environments far from anthropogenic activities regions. This indicates that 7Be AMAD values could be used as an index of air quality conditions in areas like the Po Valley. • For first time 7Be AMAD obtained by simultaneous measurements at different areas. • The 7Be AMAD values were anticorrelated with 7Be activities. • At all stations the 7Be concentrations are lower during winter and higher at summer. • The greatest 7Be AMAD values observed at the most polluted areas throughout the year. • Two or three modes revealed by inverting the initial activity distribution to smooth. [ABSTRACT FROM AUTHOR]

Analyses of 131I, 137Cs and 134Cs in airborne aerosols were carried out in daily samples at two different sites of investigation: Thessaloniki, Greece (40° N) and Milan, Italy (45° N) after the Fukushima accident during the period of March–April, 2011. The radionuclide concentrations were determined and studied as a function of time. The 131I concentration in air over Milan and Thessaloniki peaked on April 3–4, 2011, with observed activities 467 μBq m−3 and 497 μBq m−3, respectively. The 134Cs/137Cs activity ratio values in air were around 1 in both regions, related to the burn-up history of the damaged nuclear fuel of the destroyed nuclear reactor. The high 131I/137Cs ratio, observed during the first days after the accident, followed by lower values during the following days, reflects not only the initial release ratio but also the different volatility, attachment and removal of the two isotopes during transportation due to their different physico-chemical properties. No artificial radionuclides could be detected in air after April 28, 2011 in both regions of investigation. The different maxima of airborne 131I and 134, 137Cs in these two regions were related to long-range air mass transport from Japan, across the Pacific and to Central Europe. Analysis of backward trajectories was used to confirm the arrival of artificial radionuclides following atmospheric transport and processing. HYSPLIT backward trajectories were applied for the interpretation of activity variations of measured radionuclides. [ABSTRACT FROM AUTHOR]

Radioactive emissions into the atmosphere from the damaged reactors of the Fukushima Dai-ichi nuclear power plant (NPP) started on March 12th, 2011. Among the various radionuclides released, iodine-131 (131I) and cesium isotopes (137Cs and 134Cs) were transported across the Pacific toward the North American continent and reached Europe despite dispersion and washout along the route of the contaminated air masses. In Europe, the first signs of the releases were detected 7 days later while the first peak of activity level was observed between March 28th and March 30th. Time variations over a 20-day period and spatial variations across more than 150 sampling locations in Europe made it possible to characterize the contaminated air masses. After the Chernobyl accident, only a few measurements of the gaseous 131I fraction were conducted compared to the number of measurements for the particulate fraction. Several studies had already pointed out the importance of the gaseous 131I and the large underestimation of the total 131I airborne activity level, and subsequent calculations of inhalation dose, if neglected. The measurements made across Europe following the releases from the Fukushima NPP reactors have provided a significant amount of new data on the ratio of the gaseous 131I fraction to total 131I, both on a spatial scale and its temporal variation. It can be pointed out that during the Fukushima event, the 134Cs to 137Cs ratio proved to be different from that observed after the Chernobyl accident. The data set provided in this paper is the most comprehensive survey of the main relevant airborne radionuclides from the Fukushima reactors, measured across Europe. A rough estimate of the total 131I inventory that has passed over Europe during this period was <1% of the released amount. According to the measurements, airborne activity levels remain of no concern for public health in Europe. [ABSTRACT FROM AUTHOR]

First results are given from the comparison of experimental values and model calculations on accelerator-produced high specific activity radionuclides in no-carrier-added (NCA) form. The relevant radioisotopes are: 64Cu, produced by natZn(d,αxn) and natZn(d,2p) reactions, for simultaneous positron/negatron metabolic radiotherapy and PET imaging; 66Ga high-energy positron emitter (4.2 MeV), produced by natZn(d,xn) reactions, for metabolic radiotherapy and for PET; 186gRe, produced by 186W(p,n) and 186W(d,2n) reactions, for negatron (1.1 MeV) metabolic radiotherapy; 211At/211Po, produced by 209Bi(α,2n) reaction (with spike of gamma emitter 210At produced by 209Bi(α,3n) reaction) and 225Ac/213Bi/213Po, produced by 226Ra(p,2n) reaction, both for high-LET radiotherapy. [Copyright &y& Elsevier]