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Abstract  

A relatively simple method of sulphur determination in drill cores of calcium carbonate matrix is described. The method is based on the combination of measurements of backscattered beta-particles and transmitted low energy gamma-radiation intensities. The transmitted gamma-radiation measurement corrects the errors of sulphur determination caused by the varying strontium sulphate and silicon dioxide content. The method has been tested on 170 samples. It was estimated that the standard deviation of sulphur determination does not exceed 2.5% of sulphur. The apparatus for routine absorption measurement is also described.

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Abstract  

Cisplatin (CDDP) is an antineoplastic drug used in the treatment of a wide variety of tumors. This paper describes an investigation carried out on pregnant mice after intragastric or intraperitoneally treatment with CDDP from day 11 to 13 of gestation. Platinum content in different tissues, namely liver, kidney, placenta and brain, was determined at 18 day of pregnancy. Two analytical techniques were used, i.e. neutron activation analysis and atomic absorption spectroscopy. Results of both techniques are presented and discussed in terms of precision, accuracy and sensitivity. Neutron activation analysis appears to provide results better correlated with the drug treatment.

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Abstract  

A direct nondestructive method of analysis for241Am utilizing photon counting and self-absorption correction factors is presented. The method gives favorable agreement for samples analyzed by radiochemical separation procedures and alpha particle spectrometry. The comparison was made over a range of approximately five orders of magnitude of241Am concentrations. The method is reliable and relatively simple. Sensitivity for a ∼5-g sample and a counting intervals of 60 000 s is ∼0.2 pCi/g with an uncertainty of ±22%, which decreases to ±11% for increased counting intervals of 150 000 s and an increased sample size of ∼20 g.

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Journal of Radioanalytical and Nuclear Chemistry
Authors: Toshiyuki Fujii, Souichirou Egusa, Akihiro Uehara, Akira Kirishima, Isao Yamagishi, Yasuji Morita, and Hajimu Yamana

Abstract  

Palladium complexation in concentrated nitric acid solutions was studied by UV/Vis absorption spectrophotometry. The ionic strength of the solutions was fixed to I = 1, 3, or 5 mol dm−3 (M) by mixing of HNO3 and HClO4. The major palladium species were found to be Pd2+, PdNO3 +, and Pd(NO3)2. The formation constant of PdNO3 + was determined to be β 1 = 1.32 (I = 1 M), 1.49 (I = 3 M), or 1.47 (I = 5 M), while that of Pd(NO3)2 to be β 2 = 0.45 (I = 3 M) or 0.14 (I = 5 M).

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Abstract  

Ca-47 radioactive tracer was used to determine the phamocodynamics, distribution pattern, absorption and bioavailability of a new type calcium supplement in rabbit prepared by plasma technology. Our results indicate that calcium from the new nutrient is mainly deposited in bone 6 or 7 days after oral administration. The absorption rate of this new calcium preparation is estimated to be 30–40 %.

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Abstract  

Neutron activation analysis and atomic absorption spectrometry (graphite furnace) methods for the analysis of selenium in human tissue are described. The sensitivity (10–30 ng/sample), accuracy and precision are of the same order for both techniques and the choice can only be made on grounds of urgency or convenience. AAS should be chosen for the analysis of wet tissue or the urgent analysis of small numbers of dry tissue. NAA should be chosen for the analysis of large numbers of dry tissue samples where time is not important. The selenium concentration of human liver is shown to be in the region of 1 to 2 ppm (dry weight). Selenium may be lost from tissue during freeze drying if the samples are not maintained at −35°C.

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Abstract  

The reduction of hexavalent to trivalent uranium by mercury cathode electrolysis in hydrochloric acid solution was investigated. The dependence of the reducton ratio on the different media, the acid and uranium concentrations, and on the time of electrolysis was determined. It was found that hexavalent uranium can be reduced quantitatively to trivalent state by mercury cathode electrolysis. The absorption spectra of U(III) and U(IV) in 1M and 9M hydrochloric acid solutions were examined. The molar extinction coefficient of U(III) at 521 nm was 16.7 m2·mol–1 within the HCl concentration range of 0.5–4.5M. U(IV) practically does not interfere in the photometric determination of U(III) at this wavelength. A good linear dependence of absorbance on the concentration of U(III) was found.

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Abstract  

A method of uranium determination in organic and aqueous solutions has been developed, based on fluorescence L X-ray excitation with a109Cd source of several mCi activity and counting the excited Lα lines with a proportional counter. To eliminate uranium X-ray absorption by the accompanying elements the intensity of the source radiation (Ag K) transmitted through the analysed solution is measured. The ratio of these two intensities is independent of other elements present in the solution over a very broad range of concentration. The analysis time does not exceed 5 minutes. The precision and accuracy of this method in the range 0.5 to 100 g U/1 are comparable to those of the classical titrimetric method.

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Elméleti háttér: A 19-tételes Testi Abszorpció Skálát D. Watson dolgozta ki a belső testi folyamatokra irányuló folyamatos figyelem mértékének mérésére. A kérdőív szerzőjének célja egy olyan skála kidolgozása volt, ami független a negatív affektivitástól/neuroticizmustól, egyfaktoros szerkezetű és az egészséges (nem patológiás) testi folyamatok folyamatos monitorozásának hajlamát méri. A skála mind ez idáig nem került publikálásra. Cél: Jelen munka célja a kérdőív magyar változatának elkészítése és pszichometriai értékelése volt. Módszerek: Az elkészített és visszafordítással ellenőrzött magyar verzió pszichometriai jellemzőit egyetemi hallgatók mintáján (n = 426; 38,5% ffi; átlagéletkor = 20,8 ± 1,63 év) vizsgáltuk. A résztvevők a Testi Abszorpció Skála mellett a Miller-féle Személyes Testi Tudatosság Skálát (PBCS), a rövidített WHO Jól-lét Kérdőívet (WHO-5), valamint a Pozitív és Negatív Affektivitás Kérdőívet (PANAS) töltötték ki. Eredmények: Az eredmények alapján a kérdőív jó belső konzisztenciával (Cronbach-alfa = 0,84) bír, az egyfaktoros struktúrát megerősítő faktorelemzéssel ellenőriztük (CMIN = 636,697, df = 152, p < 0,001; CMIN/df = 4,189; NFI = 0,902; TLI = 0,912; CFI = 0,898; RMSEA = 0,087 [0,080—0,094]). A Testi Abszorpció Skála függetlennek bizonyult a negatív affektivitástól (Kendall tau-b = 0,02; p = 0,515), jól korrelált a személyes testi tudatossággal (Kendall tau-b = 0,43; p < 0,001) és gyenge pozitív irányú együttjárást mutatott a pozitív affektivitással (Kendall tau-b = 0,12; p < 0,001), valamint a pszichológiai jólléttel (Kendall tau-b = 0,08; p < 0,05). Következtetések: A Testi Abszorpció Skála ideális eszköz lehet a self és az éntudatosság alapját jelentő testi tudatosság (a testérzetek nem értékelő jellegű, megfigyelői attitűddel jellemezhető reprezentációja) mérésére.

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Assays assessing non-enzymatic hydrogen peroxide antioxidant capacities are often hampered by the high UV absorption of the sample itself. This is a typical problem in studies using plant extracts with high polyphenol content. Our assay is based on comparing the 405 nm absorption of the product of potassium iodine and hydrogen peroxide in the presence and absence of a putative hydrogen peroxide reactive antioxidant. This method is free of interference with either hydrogen peroxide or antioxidant self-absorption and it is also suitable for high-throughput plate reader applications.

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