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Abstract  

Two fractions of both fulvic acids (FA) and humic acid (HA) were prepared by fractionation method of Pierce and Felbeck5 involving acid hydrolysis of soil rests. This step increases recovery of both FA and HA considerably what suggest us need for slight modification of IHSS method in some cases. The weight loss, change in organic carbon content and visible spectra are figures of merit discussed. After detailed characterization these humic substances (HS) will serve as the working standards for study of interactions between organomercurials and organic part of soil.

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To the Editor, In a recent article appearing in this Journal, Han et al. [ 1 ] reported the specific heat capacity and standard molar combustion of taurine. There are several errors in the paper, and the quality of the measured

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Abstract  

High precision gamma spectrometry measurements have been made on five sets of uranium isotope abundance reference materials for nondestructive assay (NDA). These sets are intended for international safeguards use as primary reference materials for the determination of the235U abundance in homogeneous uranium bulk material by gamma spectrometry. The measurements were made to determine the count rate uniformity of the235U 185.7 keV gamma-ray as well as the235U isotope abundance for each sample. Since the samples were packaged such that the U3O8 is infinitely thick for the 185.7 keV gamma-ray, the measured count rate was not dependent on the material density. In addition, the activity observed by the detector was collimated to simulate calibration conditions used to measure bulk material in the field. The sample-to-sample variations observed within the 5 sets of samples ranged between 0.005–0.11% (1s) with standard deviations of the mean ranging from 0.01–0.02%. This observed variation appears to be due predominantly to counting statistics and not to material inhomogeneity and/or packaging. The results of this study indicate that accuracy of235U determinations via gamma spectrometry, in the range of few hundredths of a percent (2), is achievable. The main requirement for achieving this level of accuracy is a set of standards whose235U isotope abundances are known to within 0.01% (2).

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Abstract  

In order to determine the elemental concentrations of three new soil standard reference materials SRMs 2709, 2710 and 2711 from the National Institute of Standards and Technology (NIST), a comparative study of different medium-lived neutron activation analysis methods was carefully performed. Three irradiation conditions (1-hour thermal, 1-hour epithermal and 5-minute epithermal) and two counting modes (normal and Compton suppression) have been evaluated for following ten elements: As, Au, Cd, Ga, K, La, Mo, Sb, Sm, and W. The results show that the method of 5-minute epithermal and a 1-day decay is the optimum way to analyze Ga, while the addition of the Compton suppression is very beneficial for the determination of K. Using the Compton suppression system in conjunction with the 1-hour epithermal and a 1-week decay, is ideal to determine Au, Cd, Mo and W, while routine 1-hour thermal and a 1-week decay, is adequate to determine As, Sb, Sm and La in concentrations found in soil.

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Abstract  

The standard sublimation enthalpies of (2,4,5-trichlorophenoxy)acetonitrile and (2,4,5-trichlorophenoxy)aniline were determined by isothermal thermogravimetry using the Langmuir equation and by non-isothermal differential scanning calorimetry for comparison. The used procedure was previously tested using three reference compounds: benzoic acid, succinic acid and salicylic acid. The results compared to those reported in literature show an excellent agreement for two of the three compounds while the third agrees quite well. For (2,4,5-trichlorophenoxy)acetonitrile and (2,4,5-trichlorophenoxy)aniline, the extrapolation of data at 298.15 K were obtained, respectively: Δsub H(298 K)={(1064) and (1014)} kJ mol–1. From Clausius Clapeyron equation obtained after the determination of the vaporization constant α′, the following standard sublimation entropies for (2,4,5-trichlorophenoxy)acetonitrile and (2,4,5-trichlorophenoxy)aniline equal to Δsub S(298 K)=(251 and 237) J K–1 mol–1, respectively, were derived, with an error of 4 J K–1 mol–1 equal for the studied herbicides.

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Abstract  

The heat capacities (C p,m) of 2-amino-5-methylpyridine (AMP) were measured by a precision automated adiabatic calorimeter over the temperature range from 80 to 398 K. A solid-liquid phase transition was found in the range from 336 to 351 K with the peak heat capacity at 350.426 K. The melting temperature (T m), the molar enthalpy (Δfus H m 0), and the molar entropy (Δfus S m 0) of fusion were determined to be 350.431±0.018 K, 18.108 kJ mol−1 and 51.676 J K−1 mol−1, respectively. The mole fraction purity of the sample used was determined to be 0.99734 through the Van’t Hoff equation. The thermodynamic functions (H T-H 298.15 and S T-S 298.15) were calculated. The molar energy of combustion and the standard molar enthalpy of combustion were determined, ΔU c(C6H8N2,cr)= −3500.15±1.51 kJ mol−1 and Δc H m 0 (C6H8N2,cr)= −3502.64±1.51 kJ mol−1, by means of a precision oxygen-bomb combustion calorimeter at T=298.15 K. The standard molar enthalpy of formation of the crystalline compound was derived, Δr H m 0 (C6H8N2,cr)= −1.74±0.57 kJ mol−1.

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Az International Federation of Clinical Chemistry and Laboratory Medicine új, specifikus HbA1c-standardot állított elő. A jövőben a HbA1c-méréseket a laboratóriumok világszerte az International Federation of Clinical Chemistry and Laboratory Medicine módszere szerint standardizált tesztekkel végzik. A HbA1c mértékegysége is megváltozik az új referencia-módszer szerint. Hazai laboratóriumokban a bevezetés időpontja 2011. április 1. A megvalósítandó cél, hogy valamennyi laboratórium a standardizált módszert használja, a HbA1c-eredményeket mmol/mol egységben és az ebből visszaszámolt Diabetes Control and Complication Trial/National Glycohemoglobin Standardization Program szerinti százalékos értékben adja ki. A standardizáció eredményeként lehetővé válik a HbA1c-értékek széles körű összehasonlítása. Orv. Hetil., 2011, 152, 555–558.

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Abstract  

The radionuclide 131I has been increasingly used in nuclear medicine therapy procedures. Nowadays, the 131I source administered to the patient is manufactured in two different geometries: solution and capsules. The purpose of this study is the accurate measurement of the activity present in a 131I capsule without destroys it. The methodology to determine the capsules activity is to obtain the calibration factor of an IG12 secondary standard activity measurement system based on the IG12 well-type ionization chamber set up at Brazilian national metrology laboratory for ionizing radiation (LNMRI) of institute of radiation protection and dosimetry (IRD).The result obtained, 6.4670 ± 0.0381 × 10−18 A Bq−1, is quite similar to the calibration factor of the 131I solution contained in the standard ampoule geometry, 6.4515 ± 0.0368 × 10−18 A Bq−1. After obtaining the calibration factor it was used to measure 131I therapy capsules in order to check the performance of radionuclide calibrators of some Brazilian nuclear medicine centers.

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Háttér és célkitűzés: A Rorschach-teszt időszerűvé vált új, sine morbo standardját 2007 és 2014 között a Szegedi Tudományegyetem Pszichológiai Intézetének független kutatócsoportja készítette el. A standardizálás előkészítő és kezdeti szakaszában felülvizsgáltuk a magyar Rorschach-rendszert, jelölési alapelveket fogalmaztunk meg, módosítottunk néhány jel alkalmazásán, újakat is bevezettünk.

Módszer: A kutatásban a pszichiátriailag sine morbo, felnőtt személyek önként vettek részt, életkoruk 18 és 75 év közötti volt, iskolai végzettségük az általános iskolástól a többdiplomásig terjedt, és 118 település lakói közül kerültek ki. Az alapvető független változók kategóriáiból 32 almintát állítottunk össze, a teljes minta 1500 főből állt.

Eredmények: Az eredmények alapján vagy megerősítettük, vagy módosítottuk a mutatók korábbi jellemző értékeit és övezeteit, meghatároztuk az új mutatók referenciaértékeit, a feleletszám eltérő hatását a jelekre és mutatókra, összeállítottuk az új vulger válaszok listáját, támpontokat nyújtottunk a lokális értelmezéshez.

Következtetés: Rorschach-rendszerünk revíziója és az új standard adatai a Rorschach-teszt szükséges és elkerülhetetlen továbbfejlesztését szolgálják, validitását erősítik, reliabilitását növelik.

Background and objective: The elaboration of the new “sine morbo” standard for the Rorschach test started in 2007 and was completed in 2014 by an independent research group at the Institute of Psychology of the University of Szeged. In the preparatory and initial phases of the standardisation process, the Hungarian Rorschach system was re-examined, marking principles were defined, new signs were introduced and several indicators of the Comprehensive System, which are currently being used in most countries, were adopted into our system.

Method: The adult individuals who volunteered to participate in the study were psychiatrically “sine morbo”, came from 118 different communities, were aged 18 to 75, and had education levels ranging from primary school to multiple academic degrees. We compiled 32 subsamples from among the categories of the basic independent variables, with a total sample size of 1,500 individuals.

Results: Based on the results, we either reinforced or modified the previous characteristic values and zones of the indicators; determined the reference values of the new indicators and the different effects of the response rate on the signs and indicators; established a list of new vulgar responses; and provided guidance for local interpretation.

Conclusion: The revision ofour Rorschach system and the data of the new standard serve as a necessary improvement of the Rorschach test, strengthening its validity and increasing its reliability.

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Abstract  

Thirty four elements (Al, As, Ba, Br, Ca, Ce, Co, Cr, Cs, Dy, Eu, Fe, Gd, Hf, Ho, K, La, Lu, Mg, Mn, Na, Nd, Rb, Sb, Sc, Sm, Ta, Tb, Th, Ti, U, V, W, Yb) were determined by instrumental neutron activation analysis in the second set of Chinese geochemical standard reference materials (sediments from GSD-9 to GSD-12, soils from GSS-1 to GSS-8, rocks from GSR-1 to GSR-6) using both thermal and epithermal irradiations. Irradiation schemes designed to utilise short, medium and long-lived nuclides were employed in order to analyse major, minor and trace elements with different half-lives. The gamma-ray spectra were measured by Ge(Li) and HP(Ge) detectors. Relevant nuclear data and possible interferences are listed, and analytical results are presented and discussed.

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