Showing papers in "Journal of Radioanalytical and Nuclear Chemistry in 1980"
TL;DR: In this paper, the accuracy of literature data for 112 radionuclides of interest in (n, γ) reactor neutron activation analysis is compared with the values calculated from the experimentally determined k0-factors.
Abstract: k0-Factors and related nuclear data are tabulated for 112 radionuclides of interest in (n, γ) reactor neutron activation analysis. Whenever relevant, critical comments are made with respect to the accuracy of literature data for e. g. isotopic abundances, half-lives, absolute gamma-intensities and 2200 m · s−1 (n, γ) cross-sections. As to the latter, a comparison is made with the values calculated from the experimentally determined k0-factors, by introduction of selected literature data for the input parameters.
194 citations
TL;DR: In a study of the atmospheric deposition of trace elements in different parts of Norway, samples of the mossHylocomium Splendens were analyzed with respect to 28 elements as discussed by the authors.
Abstract: In a study of the atmospheric deposition of trace elements in different parts of Norway, samples of the mossHylocomium Splendens were analyzed with respect to 28 elements. The determination of Cu, Zn, Cd, and Pb was carried out by atomic absorption spectrophotometry, while 24 additional elements were determined by instrumental neutron activation analysis. In samples from southernmost Norway, a substantially higher concentration was found for elements such as Pb, Sb, V, Cr, Cu, Zn, As, Se, Mo, Ag, and Cd than in samples from places located in the more northerly parts of the country. The results indicate that sources which are to the south and south-west of Scandinavia, contribute significantly to heavy metal deposition in Norway.
81 citations
TL;DR: In this article, depth profiles for 39 p-induced reactions on Ni, Fe, Mn, Cr and Ti, which contribute to SCR-produced radionuclides (44≤A≤59) at energies up to 200 MeV are presented.
Abstract: In order to interpret cosmogenic radionuclides in extraterrestrial matter one has to differentiate between p- and α-induced reactions with solar (SCR) and with galactic (GCR) cosmic rays. Our earlier studies have shown that for a satisfactory description of GCR-interactions with dense matter rather few but characteristic high energy cross sections are required. In contrast, for the low and medium energy SCR-production a detailed knowledge of the respective nuclear reactions is needed. In the present study, excitation functions are presented for 39 p-induced reactions on Ni, Fe, Mn, Cr and Ti, which contribute to SCR-produced radionuclides (44≤A≤59) at energies up to 200 MeV. The excitation functions are based mainly on our own cross section measurements, partly on hybrid model predictions and to a lesser extent on experimental data from other authors. Based on these excitation functions, depth profiles for the proton induced SCR-production of46Sc,44Ti,48V,51Cr,52Mn,53Mn,54Mn,55Fe,56Co,57Co,58Co,60Co and59Ni from the 5 major targets mentioned before in extraterrestrial matter are calculated, assuming normal lunar surface conditions. Typical rigidities were adopted for the solar proton fluxes, ranging from 50 to 150 MV, which cover the rigidity values commonly observed in solar flares. In order to derive depth dependent p-fluxes from calculations of the energy loss of incoming particles, rather large differences in the respective chemical compositions had to be considered. The theoretical profiles are compared with experimental data from lunar samples, and several cosmochemical applications are discussed. They range from the study of single solar flare events by short-lived radioisotopes to the investigation of supposed long-term variations of the solar flare activity on a large times-cale of millions of years. The latter is possible by comparing the production rates of very long-lived nuclides (as for example53Mn with T=3,8·106 y) with that of short- or medium-lived nuclides. In this respect, the particular importance of44Ti (T-47.3 y) for measuring today's mean solar flare activity is pointed out. In general, the depth dependent production rates established in this work enable one to estimate the SCR-contributions to cosmogenic radionuclides from the respective target elements, thus providing a basis for a better understanding of the solar cosmic ray interaction with extraterrestrial matter.
71 citations
50 citations
TL;DR: The trace element composition of human hair is a suitable indicator of exposure to trace element pollutants as discussed by the authors, and during the implementation of an international research program, coordinated by the IAEA, on the use of nuclear methods for detecting trace element contaminants in hair, much valuable information was collected both on normal levels of trace elements and on increased levels caused by pollution.
Abstract: The trace element composition of human hair is a suitable indicator of exposure to trace element pollutants. During the implementation of an international research programme, coordinated by the IAEA, on the use of nuclear methods for detecting trace element pollutants in hair, much valuable information was collected both on normal levels of trace elements and on increased levels caused by pollution. As a result of reviewing and comparing the data, interesting observations relating to the spread of concentrations were made. Standardized procedures were elaborated for a number of analytical techniques as well as for pre-analytical preparations in the analysis of hair.
43 citations
TL;DR: In order to study “in vivo” the brain specific receptor sites of benzodiazepines, a method for carbon-11 labelling of diazepam and flunitrazepam without irradiation risk to personnel is described.
Abstract: In order to study “in vivo” the brain specific receptor sites of benzodiazepines, a method for carbon-11 labelling of diazepam and flunitrazepam without irradiation risk to personnel is described. 70 mCi (max. 140 mCi) of injectable labelled product, chemically and radiochemically pure, are obtained in 45 minutes with a specific activity of 810 Ci/m mole.
42 citations
TL;DR: Particle induced X-ray emission analysis (PIXE) and nuclear reaction analysis have been applied to multielemental analysis of human dental enamel in a proton microprobe as discussed by the authors.
Abstract: Particle induced X-ray emission analysis (PIXE) and nuclear reaction analysis have been applied to multielemental analysis of human dental enamel in a proton microprobe. The PIXE technique was excercised for the characterization of multielemental lateral distributions on and just below the sample surface. For the assessment of depth distributions of fluorine the resonant nuclear reaction19F(p,aλ)16O was used. The combination of two analytical techniques comprising both atomic and nuclear interactions in a microprobe was applied to enamel samples of different origins. One sample constituted a healthy enamel and the other one enamel from a restored tooth. The microprobe in the combined mode was demonstrated to permit the establishment of lateral, concentration gradients of elements heavier than phosphorus with a resolution of 15 μm in enamel and simultaneously of depth distributions of fluorine better than 0.7 μm. The detection limits approached, 10–25 ppm for most of the elements considered.
41 citations
TL;DR: A survey of the results of recent developments in process technology and some reference to the importance of process analytical statements with respect to plant operation is given in this article, where recommendations are made for the installation and design of analytical laboratories and some experiences are communicated in the field of analytical chemistry.
Abstract: Nowadays the PUREX process is the sole accepted reprocessing technique. Its boundary conditions change all the time: former metallic low burnup fuels have been replaced by present ceramic oxide fuels with high burnups, and tomorrow fast breeder fuels with high plutonium contents will have to be processed. In addition, more and more restrictive conditions are being imposed upon waste treatment and more and more stringent safety regulations are being felt. Within these constraints this report presents a survey of the results of recent developments in process technology and gives some reference to the importance of process analytical statements with respect to plant operation. Moreover, recommendations are made for the installation and design of analytical laboratories and some experiences are communicated in the field of process analytical chemistry.
32 citations
TL;DR: It is postulate that the level of conjugation is the critical parameter controlling the blood clearance in rabbits, and highly conjugated111In-labeled AAHSA (0.9 DTTA/HSA) showed accelerated clearance at 24 and 48 hours compared to lightly conjugate protein.
Abstract: A new bifunctional chelating agent, N′-(p-diazoniumbenzyl)-N,N N″,N″-diethylenetri-aminetetraacetic acid (DTTA) was synthesized. The compound as coupled to methyl p-hydroxybenzimidate and the resulting azoimidate was attached to lysine residues of monomeric human serum albumin (HSA) via the amidination reaction. Blood clearnace of111In-labelled DTTA conjugated to HSA (AAHSA) in rabbits was biphasic. The first phase has a clearance indistinguishable from that of125I-labeled HSA. During the second phase, the111In-labeled AAHSA was cleared more rapidly so that between 24 hours and 48 hours the percent of the injected dose of111In-labeled AAHSA in the blood was significantly lower than that of125I-labeled HSA. Highly conjugated111In-labeled AAHSA (0.9 DTTA/HSA) showed accelerated clearance at 24 and 48 hours compared to lightly conjugated protein (<0.9 DTTA/HSA). As a result we postulate that the level of conjugation is the critical parameter controlling the blood clearance.
32 citations
TL;DR: An extension of the conventional ZP model has been used with data for ten fission reactions and the method of least squares for derivation of parameters that describe the nuclear charge-distributions as discussed by the authors.
Abstract: An extension of the conventional ZP model has been used with data for ten fission reactions and the method of least-squares for derivation of parameters that describe the nuclear charge-distributions. Data for light and heavy fission products for each reaction were treated together by consideration of the complementarity of average mass numbers of precursors (A′L+A′H=AF). This treatment gave calculated yields that are essentially equal for complementary elements (ZL+ZH=ZF). The parameters determined,\(\bar \sigma Z\), the Gaussian dispersion width parameter, a linear function of ΔZ=|ZP-A′(ZF/AF)|, ZP being the Z at maximum of the curve, and\(\overline {EOZ} \) and\(\overline {EON} \), the even-odd proton and neutron yield enhancement factors, represented most data (AH⋟130–150 and the complementary light A's) moderately well, better than did oscillating functions of\(\bar \sigma Z\) and ΔZ. The\(\bar \sigma Z\) values were found to be approximately constant (0.48 to 0.62) and, generally, to increase with the average number of neutrons emitted,\(\bar v, (\partial \bar \sigma Z/\partial \bar v \cong 0.04)\). The ΔZ values at A′=140 were in the range of 0.42 to 0.50, and the slopes, ∂ΔZ/∂A′H, ranged from 0.0 to 0.03. The\(\overline {EOZ} \) factor was found to be several times larger than the\(\overline {EON} \) factor and to decrease with increasing excitation energy and with A and/or Z of the fissioning nucleus, as has been reported previously. The adequacy of the ZP model for representation of data and for prediction of yields in the high-yield mass-number regions mentioned above are discussed, and the large uncertainties that are involved in extrapolating the model to near symmetric or to very asymmetric mass and charge divisions are pointed out.
31 citations
TL;DR: In this paper, an analysis of variance on a set of 18 irradiations was made to estimate the relative importance of the causes of precision error, and the precision attained on those analytical results is sufficient to be able to construct geochemical models.
Abstract: Epithermal neutron activation analysis can usefully be used for simultaneous determination of trace elements in rocks. No chemical seperation is required in this case and consequently the precision may be better. In order to estimate the relative importance of the causes of precision error, we have made an analysis of variance on a set of 18 irradiations: 15 elements have been studied. The precision attained on those analytical results is sufficient to be able to construct geochemical models.
TL;DR: Several approximate standardization methods that do not require knowledge of the excitation function are compared with the “numerical integration method” using excitationfunction data from the literature and it is shown that these methods yield accurate results if the threshold energy of the considered reaction is high and if sample and standard have a comparable Z value.
Abstract: Standardization methods in activation analysis with charged particles are studied critically. Several approximate standardization methods that do not require knowledge of the excitation function are compared with the “numerical integration method” using excitation function data from the literature. It is shown that these methods yield accurate results if the threshold energy of the considered reaction is high and if sample and standard have a comparable Z value. A method that gives a rapid estimate of the maximum possible error is also presented. It is shown that for the “numerical integration method” the accuracy of the excitation function data has only a small influence on the overall accuracy. The influence of the accuracy of stopping power data and of possible deviations from Bragg's rule for light element standards is also considered.
TL;DR: Vanadium in serum has been investigated by the aid of neutron activation analysis and there was no correlation between the V-content and age, nor between theV- content and the cholesterol, triglycerides or the lipoprotein fractions in serum.
Abstract: Vanadium in serum has been investigated by the aid of neutron activation analysis (8 min irradiation at 8·1013 n·cm−2·s−1 in the reactor FR-II of the Kernforschungszentrum in Karlsruhe). The lyophilized samples were dry-ashed before irradiation and the52V activity extracted after irradiation. The values for V in the sera of 22 healthy males ranged from 0.029–0.939 ng V·ml−1. There is a real assumption that some of the high figures are due to persons being contaminated with V. The 18 healthy females yielded a mean value of 0.033±0.012 ng V·ml−1 for 17 of them and one additional value of 0.139 ng V·ml−1. These V-data are the lowest ever reported in the literature. The analyses of two packed blood cell samples yielded 0.031 and 0.020 ng·g−1, indicating that about 68% of the total V in blood is present in serum. There was no correlation between the V-content and age, nor between the V-content and the cholesterol, triglycerides or the lipoprotein fractions in serum.
TL;DR: The trace element composition of whole blood has been investigated in adult population in Bangladesh by analyzing blood samples using the external beam PIXE method and the frequency distributions of all the elements measured are presented.
Abstract: The trace element composition of whole blood has been investigated in adult population in Bangladesh. The population was formed of one hundred individuals randomly selected from a working community of five hundred adults. The blood samples were freeze dried and analyzed using the external beam PIXE method. In this analysis, proton beams of 2 MeV energy and about 30 nA current were used for characteristic X-ray excitation. The concentration of eight elements, K, Ca, Fe, Cu, Zn, Br, Rb and Pb were determined by comparison with a calibration obtained from NBS orchard leaves. The frequency distributions of all the elements measured are presented and the results are compared with available data.
TL;DR: The dependence of the distribution coefficients on the hydrogen ion concentration and HDEHP concentration in the process of extraction from lactic acid solutions in the presence of DTPA and without it has been investigated in this article.
Abstract: The dependence of the distribution coefficients on the hydrogen ion concentration and HDEHP concentration in the process of extraction from lactic acid solutions in the presence of DTPA and without it has been investigated. It has been shown that when the lactate ion concentration is higher than 0.01M, Cm is extracted predominantly as the first lactate complex. The presence of DTPA does not change the extraction mechanism. Similarity of the observed regularities for trivalent actinides and lanthanides is confirmed by the extraction of Bk(III), Ce(III), and Eu(III). It is suggested that the nature of carbonic acid used in TALSPEAK-process greatly influences the efficiency of group separation of TPE and lanthanides. It is supported by some experimental data. The extraction and stability constants of the first lactate complex (Cm Lact2+) have been found to be: Ke=2, β 1 0 = 7,7 · 103. In the practical lactic acid concentration range (1 M) the unextractable complex, Cm Lact3, is also formed in the aqueous phase. The stability constant of this complex has been found to be β 3 0 = 1.2 · 107.
TL;DR: In this paper, a rapid and precise method of determining radiocesium corresponding to 5 mrem/y, the Japan AEC's guideline, was proposed, which took only 3 hours to carry out all the procedures the authors proposed.
Abstract: A rapid and precise method of determining radiocesium corresponding to 5 mrem/y, the Japan AEC's guideline, was proposed. The development and practical performance of cesium-selective resin and the determination method was described in this paper. The resin was prepared by the formation of ammonium molybdophosphate in the structure of Amberlite XAD-7 resin. It took only 3 hours to carry out all the procedures the authors proposed. This value represents 1/10∼1/2 of the time of conventional method. The concentration of137Cs and134Cs in sea water was determined to be 0.13∼0.16 pCi/1 and less than 7.1·10−2 pCi/1, respectively.
TL;DR: The proceedings of the IAEA symposium held in 1978 on nuclear activation techniques in the life sciences are reviewed in this paper, where a total of 56 papers are reviewed on methodology, analytical quality control, comparisons between neutron activation analysis and other methods, and applications of activation analysis in biology and medicine (including in-vivo activation analysis) and in public and environmental health.
Abstract: The proceeding of the IAEA symposium held in 1978 on nuclear activation techniques in the life sciences are reviewed. A total of 56 papers are reviewed on methodology, analytical quality control, comparisons between neutron activation analysis and other methods, and applications of activation analysis in biology and medicine (including in-vivo activation analysis) and in public and environmental health. The materials analysed in the papers are adjusted in connection with the elements determined and the purposes of the study. Those elements are tabulated together with the analytical methods used for the element determination. The standard reference materials analysed for the check of the reliability of analysis are also arranged.
TL;DR: A new method for the production of13N-labelled ammonia is described and its application in selective separation of Na6(CO3)(SO4)2, Na2SO4 and Na2CO3 is described.
Abstract: A new method for the production of13N-labelled ammonia is described.
TL;DR: In this article, a rapid radiochemical procedure for the separation of iodine has been devised, which is characterized by extremely high decontamination factors so as to give pure128I spectra with biological materials containing large concentrations of interferring elements such as sodium, bromine and chlorine.
Abstract: A rapid radiochemical procedure for the separation of iodine has been devised, which is characterized by extremely high decontamination factors so as to give pure128I spectra with biological materials containing large concentrations of interferring elements such as sodium, bromine and chlorine. The method is based on ignition in oxygen followed by an oxidation-reduction and extraction-stripping cycle involving nitrite, sulfite and carbon tetrachloride. Results are presented for ten NBS and IAEA reference materials, frequently referred to in the literature.
TL;DR: In this paper, a high resolution Ge(Li) gamma ray spectrometer was used to determine the concentration of Al, As, Au, Br, Ca, Cd, Co, Cr, Cu, Fe, La, Mn, Mo, Sb, Se, W, and Zn in Cumin, coriander, carrots, and Daucus carrota (Umbelliferae Family), alfalfa, Kidney bean, phaseolus sativus, Phaseolus vulgaris, bean, lenses, and fenugreek (
Abstract: Neutron activation analysis, NAA, a high resolution Ge(Li) gamma ray spectrometer was used to determine the concentration of Al, As, Au, Br, Ca, Cd, Co, Cr, Cu, Fe, La, Mn, Mo, Sb, Se, W, and Zn in Cumin, coriander, carrots, and Daucus carrota (Umbelliferae Family), alfalfa, Kidney bean, Phaseolus sativus, Phaseolus vulgaris, bean, lenses, and fenugreek (Legumirosae Family). Multielement determination technique on destructive and nondestructive samples was followed. This method is simple, precise and sensitive to 17 trace elements.
TL;DR: In this paper, the retention of UO2(CO3)34− on titanium oxide has been studied and a retention mechanism of the ligang-exchange type has been proposed.
Abstract: We have studied the phenomenon of retention of uranium, as a carbonato complex UO2(CO3)34− on titanium oxide. We first proposed a method for preparing titanium oxide whose ion-exchange capacities (2.9 meq Na+/g, 0.11 meq UO22+/g) and physical properties (mechanical resistance and granulometry) make it quite suitable for liquid chromatography and particularly for the extraction process of uranium from sea-water. We prepared the sodium tricarbonatouranate, the major form of uranium in sea-water. We studied the retention of this compound on titanium oxide. From a thermodynamic study of the retention equilibrium we proposed a retention mechanism of the ligang-exchange type: uranyl is retained on titanium oxide, surrounded with two CO32− ligands and two ≥TiO− ligands. We shown that 2/3 of the exchanged hydroxyl groups have pKH1=4.9 and 1/3 of them have pKH2=9.3.
TL;DR: In this article, the improvement of detection limits for trace elements in geological samples by epithermal neutron activation analysis is examined, and the relative merits of Cadmium, boron and composite cadmium+boron filters are compared for trace element Ni, As, Pd, Cd, Sb, W, Ir, Pt and Au, and interfering elements Na, K, Sc, Cr, Fe, Co and Cu.
Abstract: The improvement of detection limits for trace elements in geological samples by epithermal neutron activation analysis is examined. The relative merits of cadmium, boron and composite cadmium+boron filters are compared for trace elements Ni, As, Pd, Cd, Sb, W, Ir, Pt and Au, and interfering elements Na, K, Sc, Cr, Fe, Co and Cu. A boron filter gives optimum sensitivity for the trace elements based on interference from46Sc, but the detection limits are only improved 2–5 times. Ma imum possible improvement, which is shown by Ni, gives sensitivities 5 times better under cadmium and 15 times under boron.
TL;DR: In this paper, a comparative study is presented on neutron activation analysis of rock and soil samples using whole reactor neutron spectrum and epithermal neutrons with both relative and monostandard procedures.
Abstract: A comparative study is presented on neutron activation analysis of rock and soil samples using whole reactor neutron spectrum and epithermal neutrons with both relative and monostandard procedures. The latter procedure used with epithermal neutron activation analysis of soil samples necessitated the use of the “effective resonance integrals” which were determined experimentally. The incorporation of the β factor, representing deviation of reactor epithermal neutron flux from 1/E law, is developed in the present work. The main criteria for the choice of one or more of the procedures studied for a given purpose are also indicated. Analysis of 15 trace elements, Ca and Fe in the standard Japanese granite JC-1 using monostandard epithermal neutron activation gave results in good agreement with the average literature values.
TL;DR: In this paper, the use of boron carbide as a thermal neutron filter in epithermal neutron activation (ENAA) analysis has been investigated, and the results show that the filter has a relatively low level of induced activity which poses minimal radiation safety problems when used for ENAA.
Abstract: The use of boron carbide as a thermal neutron filter in epithermal neutron activation (ENAA) analysis has been investigated. As compared to the use of a cadmium filter, boron provides a greater reduction of activities from elements relatively abundant in terrestrial rocks and fossil fuels, such as Na, La, Sc and Fe. These elements have excitation functions which follow the 1/v law in the 1 to 10 eV lower epithermal region. This enhances the sensitivity of ENAA for elements such as U, Th, Ba and etc. which have strong resonances in the higher epithermal region above 10 eV. In addition, a boron carbide filter has the advantages over cadmium of acquiring a relatively low level of induced activity which poses minimal radiation safety problems, when used for ENAA.
TL;DR: The fly ash of a waste incineration facility in Berlin, Germany has been found to be a very useful multielement reference material as discussed by the authors, which can be used for a large number of matrices to be analyzed.
Abstract: Fly ash of a waste incineration facility in Berlin, Germany has been found to be a very useful multielement reference material. It can be used for a large number of matrices to be analyzed. It has served as a reference material particularly for environmental multielement analyses. Components which have been recognized as environmental pollutants are present in higher concentration levels than in any other multielement reference material commercially available.
TL;DR: In this article, the authors analyzed the contribution and performance of NAA as compared to other techniques and showed that NAA is the method of good accuracy and precision providing on average greater share of results than any other single analytical technique.
Abstract: Results of several IAEA intercomparison runs organized over the last 8 years are analyzed from the point of view of contribution and performance of NAA as compared to other techniques. It is shown that NAA is the method of good accuracy and precision providing on average greater share of results than any other single analytical technique. The prominent position of NAA among other methods used in trace analyses seems to be firmly established and there are no signs that there might be any change of the trend in the nearest future.
TL;DR: In this article, the aluminum and phosphorus levels in bone powder and in human bone biopsies were determined with the use of the pneumatic tube system of the BER II reactor, the irradiation position of which is equipped with a movable cadmium shield.
Abstract: With the use of the pneumatic tube system of the BER II reactor, the irradiation position of which is equipped with a movable cadmium shield, the aluminium and phosphorus levels in bone powder and in human bone biopsies were determined. The contribution of aluminium and phosphorus to the28Al activity could be separated mathematically after the samples had been irradiated with and without cadmium shielding. The sensitivity and limit of quantitative determination of the analytical procedure were determined using the addition method and the fact that the levels of each element measured was independent of the amount of the other element was proved.
TL;DR: The Lake Nasser reservoir as mentioned in this paper is the largest man-made lake in the world and is the reservoir created by the High Dam in the southermost part of Egypt and extends beyond Daal Cataract in the Sudan.
Abstract: Lake Nasser, one of the largest man made lakes in the world, is the reservoir created by the High Dam in the southermost part of Egypt and extends beyond Daal Cataract in the Sudan. The reservoir is about 480 kms long, of which, 300 kms are in Egypt (Lake Nasser) and 180 kms in the Sudan (Lake Nubia) and extends approximately within the latitudes of 21 No in the Sudan and 24 No in Egypt. In the west is the Great Western Desert and in the east the Eastern Desert of Egypt which extends up to the Red Sea.
TL;DR: In this article, the radiochemical neutron activation technique used consists of five stages; viz. sample digestion, cation exchange chromatography, irradiation and counting, where the columns are eluted with 2M HCl to remove unwanted elements and rare earth elements are subsequently desorbed with 6M HCI.
Abstract: The radiochemical neutron activation technique used consists of five stages; viz. sample digestion, cation exchange chromatography, irradiation and counting. Silicate samples are decomposed using a conventional hydrofluoric/perchloric acid digestion followed by loading the solutions, as chlorides, onto cation exchange resin columns. The columns are eluted with 2M HCl to remove unwanted elements and the rare earth elements are subsequently desorbed with 6M HCI. A tracer,144Ce, is used to monitor the chemical yields and studies show that no fractionation or loss of any REE occurs. The REE abundances of five reference samples (NIM-G, SY-2, MRG-1, JB-1 and BOB-1) show that the described procedure is capable of providing good accuracy and precision. The method has some advantages over conventional INAA and RNAA and these are described.
TL;DR: In this article, a sensitive method of carbon determination in silicon by activation with deuterons and3He particles followed by chemical separation of the measured nuclides13N and11C has been developed.
Abstract: A sensitive method of carbon determination in silicon by activation with deuterons and3He particles followed by chemical separation of the measured nuclides13N and11C has been developed. Aside from the etch removal after irradiation, it is essential for a low detection limit to avoid too much thermal exposure of the target surface during the irradiation process, or else microflaw formation and diffusion on the surface have to be anticipated. The ion current must have an optimal rather than a maximum value.