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An application of a simple computer program for neutron activation analysis.

A simple computer program is designed for estimation of elemental concentration values in complex samples by neutron activation analysis technique. The program is applied for an Egyptian cement sample which irradiated at the Egyptian Research Reactor-1(ET-RR-1). The data obtained is compared with the reported values. The time consumed for such calculations has a remarkable reduction in comparison with the routine work.

Construction Materials↗

[Non-destructive neutron activation analysis of dental porcelain powders (author's transl)].

Determination of 15 elements in the dental porcelain powders (Vita VMK 68) marketed in Japan was done by means of non-destructive neutron activation analysis. The potassium and sodium contents showed less variations from powder to powder, and the uranium contents varied from a few ppm to 1090 ppm in a wide range. The high contents of uranium (345--1090 ppm) were detected in the powders of Enamel, Dentin, Effect, Color and Gum which were used for the superficial parts of a porcelain crown, while the low contents of uranium (1.6--2.7 ppm) were detected in those of Opaque and Translucent which were used for the core part and the top of the crown. Cerium and samarium were also detected in each powder in the amounts similar to those of uranium. The main radionuclides present in the porcelain powders were 238U, 235U, 234U, 234mPa, 234Th, 231Th and 40K. The activities of these nuclides were calculated and discussed.

Activation Analysis↗

The determination of calcium in faecal samples by instrumental fast neutron activation analysis.

A method is described for the determination of calcium in faecal material by a purely instrumental technique, namely fast neutron activation analysis. The major advantage of the technique over existing methods is that it requires minimal sample preparation. In addition, only a single standard is used and the method is also fairly rapid and simple. The method is well suited to the routine analysis of large numbers of samples and the results are shown to be comparable with atomic absorption spectrophotometry in accuracy. Finally, the technique can be extended to include the determination of several other elements providing a standard for each element is included.

Activation Analysis↗

Quantitation of seven elements in Mycobacterium phlei and Mycobacterium bovis by neutron activation analysis.

Quantitative determination of the elements potassium, sodium, manganese, magnesium, iron, cobalt and zinc was performed in mycobacteria by neutron activation analysis. Mycobacterium phlei ATCC 19 249 at different phase of growth (4, 8, 13, 23 and 37 days old cultures), and 14 days old Mycobacterium bovis BCG cultures and uninoculated semi-synthetic Sauton culture media were examined. The elements studied could be divided into three groups; sodium, potassium and magnesium could be regarded as major, iron as minor, and zinc, manganese and cobalt as trace elements. M. phlei contained, with the exception of zinc, higher amounts of elements than M. bovis. Other metals (aluminium, antimony, rubidium) could also be detected.

Activation Analysis↗

[Identification of hashish samples with inductively coupled high-frequency plasma emission spectrometry and neutron activation analysis and data handling with neuronal networks. 1. Methods for the quantitative determination of characteristic trace elements].

Neutron activation analysis (NAA) and inductively coupled plasma emission spectrometry (ICP-AES) were used to quantify the relative contents of Fe, Sc, Ce, Pa, Cr, Co, respectively the absolute contents of Cr, Zn, Mn, Fe, Mg, Al, Cu, Ti, Ca, Sr in hashish samples, seized in different countries. The samples were processed after dry ashing by means of instrumental NAA and after wet mineralization by means of ICP-AES. For determination of the sampling and measurement errors, one of the samples was analyzed repeatedly with both methods. Classifying hashish samples with regard to concentration of certain elements could be done by artificial neural networks with a modified backpropagation algorithm. By this way, identity and non identity of one unknown sample with one of many different samples as data pool can be ascertained, on principle.

Cannabis↗

Selenium determination in whole human blood by radiochemical neutron activation analysis: preliminary results in Argentina.

In Argentina there are no values regarding the content selenium in food or its effect on nutritional status. Neutron activation analysis and a radiochemical separation scheme for selenium has been adjusted for blood samples from healthy adult individuals. Fasting whole blood was collected, lyophilized, packed, and irradiated in a nuclear reactor. Selenium was determined by a radiochemical separation. The method was validated using certified reference materials. The selenium concentrations (mean value +/- SD) from five pools and from 22 individual samples were 0.070 +/- 0.020 microgram/ml and 0.071 +/- 0.014 microgram/ml, respectively, ranging between 0.047 to 0.105 microgram/ml. These preliminary results show values close to those published for the population living in areas with adequate selenium intake, but lower values than those published for the USA population. However, it will be necessary to carry out nutritional status studies in other areas of Argentina, taking into account the geographic and topographic diversity of the country.

Adolescent↗

Non-destructive neutron activation analysis of aluminium and phosphorus in bone biopsies.

The level of aluminium and phosphorus in bone was measured by neutron activation analysis via the short lived radionuclide 28Al. The contribution of both elements to the 28Al activity could in each case by determined after the samples had been irradiated twice, once with a cadmium shield around the irradiaion position. The samples were analysed non-destructively and may later be used for further tests. Limits for the quantitative determination of aluminium and phosphorus in usual bone biopsies were calculated.

Activation Analysis↗

Simultaneous determination of iron, zinc, selenium, rubidium, and cesium in serum and packed blood cells by neutron activation analysis.

We determined the iron, zinc, selenium, rubidium, and cesium concentrations in serum and packed blood cells by instrumental neutron activation analysis without chemical separations. Lyophilized samples were irradiated for 12 days at a flux of 10(13) neutrons-cm-2-s-1, mineralized by wet digestion, and measured two times with a high-resolution Ge(Li) detector--for 6 h about a month after the irradiation and for 15 h two or three months after the irradiation, The following values were obtained: 163 +/- 0.43 mg/liter (serum iron), 1025 +/- 136 mg/kg wet wt (packed cells iron), 1¿ +/- 0.20 mg/liter (serum zinc), 11.15 +/- 1.83 mg/kg wet wt (packed cells zinc), 0.13 +/- 0.02 mg/liter (serum selenium), 0.16 +/- 0.03 mg/kg wet wt (packed cells selenium), 0.17 +/- 0.04 mg/liter (serum rubidium), 4.28 +/- 0.98 mg/kg wet wt (packed cells rubidium), 0.74 +/- 0.20 microgram/liter (serum cesium), and 4.82 +/- 2.10 microgram/kg wet wt (packed cells cesium).

Blood Cells↗

A comparison of methods of assessment of body composition including neutron activation analysis of total body nitrogen.

Fourteen healthy men underwent determinations of total body nitrogen (TBN) by prompt gamma neutron activation analysis and total body potassium (TBK) by whole body counting to estimate the muscle and nonmuscle components of the fat-free body mass (FFBM) and their protein contents. Comparison of FFBM estimated from TBN and TBK (60.6 +/- 6.9 kg, mean +/- SD), densitometry (62.3 +/- 7.1 kg), TBK alone (62.2 +/- 8.0 kg) and TBW (63.9 +/- 7.8 kg) showed no differences among the techniques. Similarly, there were neither differences in fat mass nor percent body fat among the methods. Analysis of the chemical composition of FFBM of this group showed TBK/FFBM = 62.6 +/- 2.3 mEq/kg, TBW/FFBM = 74.6 +/- 0.2%, TBN/FFBM = 32.74 +/- 1.09 g/kg, protein/FFBM = 20.5+/- 0.7%. The calculated mineral content of the FFBM was 6.4%. These values are strikingly similar to the values calculated by direct chemical analysis. It was concluded that the combined TBN-TBK method is a valid technique for estimating body composition in man.

Adipose Tissue↗

Elemental investigation of some Egyptian vehicle motor alloys using neutron activation analysis.

Six samples of different Egyptian motor vehicle alloys have been investigated by neutron activation analysis to estimate the concentrations of their elemental constituents, which affect their quality. A single high resolution hyper-pure germanium HPGe gamma-ray detector and a multichannel analyzer are used to collect the gamma-ray spectra. A HPGe-HPGe coincidence spectrometer was also used to confirm the identity of certain peaks. Thirteen trace elements (Sc, Cr, Fe, Co, Zn, Sn, Sb, La, Sm, Eu, Hf, Pt and Au) were observed in the spectra and their concentrations were determined. A comparative study on the element concentrations for the six samples is given.

Journal Article↗

[Neutron activation analysis in modelling the elimination from the kidneys of cis-dichlorodiammineplatinum].

A neutron activation analysis was used for a study of platinum elimination from the kidneys of male rats after administration of cis-DDP at a dose of 7 mg per 1 kg of the animal body mass. The literature data on beagles were taken for comparison. A simple mathematical model for platinum elimination from the kidneys was proposed: the platinum content was 2.27 micrograms per 1 g of raw tissue for the time interval of 3h less than or equal to t less than or equal to 1 day; 2.34 X X t(-0,51) micrograms/g for t greater than 1 day and a dose of 1 mg per 1 kg of the animal body mass. An opportunity to predict the platinum content in the human kidneys was tested.

Activation Analysis↗

Simplified measurement of protein-bound iodine with epithermal neutron activation analysis.

A refined method for the measurement of protein-bound iodine (PBI) in blood serum was demonstrated by the use of epithermal neutron activation analysis (ENAA). PBI in ammonium sulfate-precipitated serum protein, after epithermal neutron activation, was determined by high resolution gamma-ray spectrometry. From our results, the PBI concentration was 67.8 +/- 2.2 ng/mL. Good agreement was obtained with published data, ranging from 40 to 80 ng/mL, which had been obtained using different analytical techniques. The validity of these techniques for PBI has been born out by a very good accuracy and simplicity without temperature dependence.

Adult↗

Neutron activation analysis of normal and cadmium injected rat liver using ammonium pyrrolidinedithiocarbamate extraction.

A radiochemical group separation using APDC extraction was applied to the neutron activation analysis of normal and cadmium injected rat liver. In order to optimize determinations of induced radionuclides with various half lives, the gamma-ray spectra were obtained after various decay times. Eight elements, Cd, Co, Cu, Fe, Mn, Mo, Se and Zn, were determined from rat liver samples within 12 day after irradiation. Although Cd, Cu and Mo in normal rat liver could not be detected by nondestructive method, they could be determined after the extraction. The tendency was seen that the concentration of all the elements as mentioned above are increased by cadmium injection. In particular, zinc and copper exhibited high values.

Activation Analysis↗

Determination of trace elements in normal and diabetic whole blood by neutron activation analysis.

The concentration of 10 trace elements in samples of normal and diabetic whole blood were investigated by neutron activation analysis (NAA). Instrumental NAA (INAA) was used for determination of Co, Cr, Hg, Rb, Se, and Zn, whereas NAA with radiochemical separation (RNAA) was employed for determination of Al, Cu, Mg, and Mn. The results for normal blood compare well with literature values. Co, Cr, Se, and Zn show lower values in diabetes than in the normal blood samples.

Adolescent↗

Characterization of airborne particulates in Bangkok urban area by neutron activation analysis.

Samples of airborne particulates were collected in a residential area and in an area near a busy highway in Bangkok during the period from January 1997 to May 1998. A stacked filter system was used for the former site and a Partisol 2000 was used for the latter site. Both 2.5 microns and 10-micron particulates were collected every week. The total suspended particulate matters were also collected at the latter site. The samples were analyzed by neutron activation analysis utilizing neutron flux from a 2-MW TRIGA MARK III research reactor. The elements most frequently detected in the airborne particulates were Al, As, Br, Ca, Ce, Cl, Co, Cr, Cs, Fe, I, K, La, Mg, Mn, Na, Rb, Sb, Sc, Sm, Th, Ti, V, and Zn. The enrichment factor and factor analysis were used to investigate trends, sources, and origin of the atmospheric aerosols. Anthropogenic elements in road dust, construction dust, motor vehicles emission, and other combustion components were identified. A comparative study of data between both sites was performed and it was found that the mass concentration in the area close to the highway was about three times higher than in the residential area.

Aerosols↗