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Provenancing of drugs based on their elemental composition determined by Neutron Activation Analysis - Feasibility Study
Kučera, Jan; Kameník, Jan; Sabol, J.; Šesták, B.; Kolář, P.; Roman, M.
2018 - Czech
We analyzed five samples of heroine and five samples of cocaine seized in the Czech Repulic using instrumental neutron activation analysis (INAA). In the heroine speciments, we determined 16 trace elements in at least one of the samples analyzed, in the cocaine speciment, 9 trace elements could be determined. We have found remarkable differences, up to several orders of magnitude, in contents of the elements Na, Cl, Zna and Br, especially in the heroine samples. The accuracy of INAA results was proved by simultaneous analysis of a certified reference material NIST SRM 1547 Peach Leaves. The results of trace element determination in heroine samples are compard with those published by autors from abroad. The results obtained show a high potential of INAA for the drug elemental characteriaztion aimed at determination of their provenance, procedures used for their manufacturing and purification and cutting for the end users. The results achieved also suggest that it is desirable to analyze more samples with the final aim of establishing a database of elemental composition of drugs seized in the Czech Republic, which could possibly be extended later, in cooperation with foreign drug abuse and police bodies, at the international level. Analyzovali jsme pět vzorků heroinu a pět vzorků kokainu zachycených na území České republiky metodou instrumentální neutronové aktivační analýzy (INAA). Alespoň v jednom z analyzovaných vzorků heroinu jsme stanovili 16 stopových prvků, ve vzorcích kokainu se jednalo o 9 stopových prvků. Pozoruhodné rozdíly až v rozmezí několika řádů, jsme zjistili v obsazích prvků Na, Cl, Cr, Zn a Br, zejména ve vzorcích heroinu. Přesnost výsledků INAA jsme prokázali simultánní analýzou certifikovaného referenčního materiálu NIST SRM 1547 Peach Leaves. Výsledky stanovení stopových prvků v heroinu jsme porovnali s výsledky zahraničních autorů. Dosažené výsledky ukazují na vysoký potenciál metody INAA pro prvkovou charakterizaci drog za účelem zjištění jejich původu, způsobu výroby a čištění či způsobu ředění pro konečné uživatele. Pokládáme za účelné pokračovat v analýzách většího množství vzorků s konečným cílem vytvoření databáze prvkového složení vzorků zkonfiskovaných na území ČR, která by později mohla být rozšířena ve spolupráci se zahraničními protidrogovými a policejními orgány v mezinárodním měřítku.
Keywords:
heroine; cocain; INAA
Available on request at various institutes of the ASCR
Provenancing of drugs based on their elemental composition determined by Neutron Activation Analysis - Feasibility Study
We analyzed five samples of heroine and five samples of cocaine seized in the Czech Repulic using instrumental neutron activation analysis (INAA). In the heroine speciments, we determined 16 trace ...
Ion beam modification of materials for optics, electronic and spintronics -ion implantation using accelerators or laser induced plasma ion generation
Macková, Anna
2016 - Czech
Ion beam modification offers a broad field of the creating the new functional materials and nano-structures for optics, electronics, spintronics and other material branches. Using ions produced by ion accelerators or implanters\nmeans the usage of the monoenergetic beams for precise doped layer, nano-particles or cluster creation by varying the ion implantation specie versus matrix combination together with the implantation energy, ion flux etc. Recently\nappears the multienergetic ion implantation which is realized by using of the intense laser shot generating plasma from the specially designed targets, where the ions are accelerated and can be then implanted into the various\nmaterials. This contribution will present an overview and comparison of different ion beam modification techniques, plasma ion implantation will be also mentioned.
Keywords:
modification; materials; ion implantation
Available at various institutes of the ASCR
Ion beam modification of materials for optics, electronic and spintronics -ion implantation using accelerators or laser induced plasma ion generation
Ion beam modification offers a broad field of the creating the new functional materials and nano-structures for optics, electronics, spintronics and other material branches. Using ions produced by ion ...
Impact of cryogenic grinding on iodine homogeneity in NIST SRM 1548a Typical Diet
Kameník, Jan; Kučera, Jan
2016 - Czech
The reference material NIST SRM 1548a Typical Diet has a certified iodine mass fraction of 0.759±0.103 mg kg-1. The expanded uncertainty is rather large (relative value 13.6 %), thus the material does not provide strict requirements for quality control results. Milling of NIST SRM 1548a at the temperature of liquid nitrogen yielded free-flowing material. Iodine mass fraction in the original and cryo-ground materials was determined by epithermal neutron activation analysis (ENAA) and radiochemical neutron activation analysis (RNAA). The average and standard deviation from both methods was 0.73±0.03 mg kg-1 (20 values). The determined mass fraction was in a close agreement with the certified value of NIST SRM 1548a, thus iodine total content was not influenced by the milling procedure. In comparison to iodine mass fraction determined in the original NIST SRM 1548a 0.72±0.07 mg kg-1 (average ± standard deviation, 14 values), the standard deviation for cryo-ground material was considerably lower. The prepared quality control material sets up more stringent requirements on the validation and quality control procedures of the measurement of iodine mass fraction in such a composite food matrices. We believe that the iodine random inhomogeneity in the original NIST SRM 1548a is due to insufficient mixing of some iodine-rich component in the complex food matrices. Milling at the temperature of liquid nitrogen offers an effective option for production of future reference materials of this kind. The reference material NIST SRM 1548a Typical Diet has a certified iodine mass fraction of 0.759±0.103 mg kg-1. The expanded uncertainty is rather large (relative value 13.6 %), thus the material does not provide strict requirements for quality control results. Milling of NIST SRM 1548a at the temperature of liquid nitrogen yielded free-flowing material. Iodine mass fraction in the original and cryo-ground materials was determined by epithermal neutron activation analysis (ENAA) and radiochemical neutron activation analysis (RNAA). The average and standard deviation from both methods was 0.73±0.03 mg kg-1 (20 values). The determined mass fraction was in a close agreement with the certified value of NIST SRM 1548a, thus iodine total content was not influenced by the milling procedure. In comparison to iodine mass fraction determined in the original NIST SRM 1548a 0.72±0.07 mg kg-1 (average ± standard deviation, 14 values), the standard deviation for cryo-ground material was considerably lower. The prepared quality control material sets up more stringent requirements on the validation and quality control procedures of the measurement of iodine mass fraction in such a composite food matrices. We believe that the iodine random inhomogeneity in the original NIST SRM 1548a is due to insufficient mixing of some iodine-rich component in the complex food matrices. Milling at the temperature of liquid nitrogen offers an effective option for production of future reference materials of this kind.
Keywords:
SRM1548a Typical Diet; epithermal neutron activation analysis; radiochemical neutron activation analysis
Available at various institutes of the ASCR
Impact of cryogenic grinding on iodine homogeneity in NIST SRM 1548a Typical Diet
The reference material NIST SRM 1548a Typical Diet has a certified iodine mass fraction of 0.759±0.103 mg kg-1. The expanded uncertainty is rather large (relative value 13.6 %), thus the material does ...
Determination of reference values of element contents in certified reference material SWCNT-1 by INAA a PGAA
Kučera, Jan; Sturgeon, R. E.; Grinberg, P.; Oflaz, R.; Paul, R. L.; Bennett, J. W.; De Nadai Fernandes, E. A.; Kubešová, Marie; Bacchi, M. A.; Stopic, A. J.
2014 - Czech
Instrumental neutron activation analysis with both relative and k-0 standardization was used in four experienced laboratories to determine element mass fractions in single-wall carbon nanotube certified reference material (CRM) SWCNT-1. Results obtained were evaluated using the NIST “Type B On Bias” approach and yielded consensus values in agreement with NRCC certified values for Fe, Co, Ni and Mo and provided mass fraction values for thirteen additional elements, namely Na, Mg, Al, K, Ca, Ti, V, Cr, Mn, Br, La, W and Au. In addition, prompt gamma neutron activation analysis was employed to determine mass fractions of H, B, Co, Ni, and Mo. Results of this work provide a basis for the establishment of reference values of element mass fractions in CRM SWCNT-1, thus expanding its usability for more accurate characterization and benchmarking of similar nanotechnology materials.
Keywords:
carbon nanotubes; neutron activation analysis
Available at various institutes of the ASCR
Determination of reference values of element contents in certified reference material SWCNT-1 by INAA a PGAA
Instrumental neutron activation analysis with both relative and k-0 standardization was used in four experienced laboratories to determine element mass fractions in single-wall carbon nanotube ...
Nondestructive determination of nitrogen in biological and other materials by photon activation analysis
Krausová, Ivana; Mizera, Jiří; Chvátil, David; Krist, Pavel; Řanda, Zdeněk; Kučera, Jan; Štursa, Jan
2013 - Czech
A procedure has been developed for assaying nitrogen in biological materials by means of instrumental photon activation analysis (IPAA). The determination has been based on counting of the non-specific 511 keV annihilation gamma rays of 13N, product of the photonuclear reaction 14N(γ, n)13N and a pure positron emitter. IPAA allowed determination of nitrogen down to 1 wt.%. in selected biological reference standards - NIST RM 8433 Corn Bran, 1547 Peach Leaves, 8414 Bovine Muscle, and 1577b Bovine Liver. The optimized procedure was applied also to assaying nitrogen in pulverized nanodiamond intended for medical purposes. Byl vyvinut postup instrumentální gama aktivační analýzy (IGAA) pro stanovení dusíku v biologických materiálech. Stanovení je založeno na měření nespecifického anihilačního záření gama o energii 511 keV emitovaného 13N, který je produktem fotojaderné reakce 14N(γ, n)13N a je čistým pozitronovým zářičem. Metoda IGAA umožnila stanovení dusíku pod úrovní 1 hmotnostního procenta ve vybraných biolgických referenčních materiálech - NIST RM 8433 Corn Bran, 1547 Peach Leaves, 8414 Bovine Muscle, and 1577b Bovine Liver. Optimalizovaný postup byl také použit pro stanovení dusíku v práškových nanodiamantech pro lékařské účely.
Keywords:
instumental photon activation analysis; nitrogen; biological materials; nanodiamond
Available at various institutes of the ASCR
Nondestructive determination of nitrogen in biological and other materials by photon activation analysis
A procedure has been developed for assaying nitrogen in biological materials by means of instrumental photon activation analysis (IPAA). The determination has been based on counting of the ...
On possible parent crater for Australasian tektites: Geochemical, isotopic, geographic and ballistic constraints
Mizera, Jiří; Řanda, Zdeněk
2013 - Czech
A set of Australasian tektites (AAT) has been geochemically characterized by methods of activation analysis. Based on the acquired data as well as previously published geochemical, mineralogical, petrographical and isotopic data on both AAT and their potential source materials, and considering geographic and ballistic constraints known from other tektites and their strewn fields, probable source materials and location of the parent impact crater for AAT have been discussed. Soubor australoasijských tektitů (AAT) byl geochemicky charakterizován metodami aktivační analýzy. Na základě získaných výsledků a dříve publikovaných geochemických, mineralogických, petrografických a izotopových dat pro AAT a jejich potencionální zdrojové materiály, spolu s uvážením geografických a balistických omezení známých pro jiné tektity a jejich pádová pole, jsou diskutovány pravděpodobné zdrojové materiály a lokalizace mateřského impaktového kráteru pro AAT.
Keywords:
Australasian tektites; impact; parent crater; activation analysis
Available at various institutes of the ASCR
On possible parent crater for Australasian tektites: Geochemical, isotopic, geographic and ballistic constraints
A set of Australasian tektites (AAT) has been geochemically characterized by methods of activation analysis. Based on the acquired data as well as previously published geochemical, mineralogical, ...
How to calculate uncertainties of neutron flux parameters and uncertainties of analysis results?
Kubešová, Marie; Kučera, Jan
2013 - Czech
A novel method has been developed for the calculation of uncertainties of neutron flux parameters and element mass fractions and their uncertainties in k0-neutron activation analysis (k0-NAA) using the Kragten universally applicable spreadsheet technique. The results obtained are compared with other approaches for evaluation of uncertainties of the neutron flux parameters and element mass fractions, namely with the Kayzero for Windows, k0-IAEA and ERON programs. Byla vypracována nová metoda výpočtu nejistot parametrů neutronového toku, hmotnostních frakcí prvků a jejich nejistot v k0-neutronové aktivační analýze (k0-NAA) použitím Kragtenova univerzálního tabulkového procesoru. Získané výsledky jsou porovnány s jinými přístupy hodnocení nejistot parametrů neutronového toku a hmotnostních frakcí prvků obsaženými v programech Kayzero for Windows, k0-IAEA a ERON.
Keywords:
k0-neutron activation analysis; uncertainties of neturon flux parameters; Kragten spreadsheet technique
Available at various institutes of the ASCR
How to calculate uncertainties of neutron flux parameters and uncertainties of analysis results?
A novel method has been developed for the calculation of uncertainties of neutron flux parameters and element mass fractions and their uncertainties in k0-neutron activation analysis (k0-NAA) using ...
Determination of elemental impurities in polymer materials of electrical cables of safety systems of nuclear power plants by neutron activation analysis
Kučera, Jan; Kubešová, Marie; Bartoníček, B.
2013 - Czech
Instrumental neutron activation analysis (INAA) was employed for elemental characterization of individual components of electrical cables currently used in safety systems of nuclear power plants (NPP). The analysis yielded information about the content of 35 elements. It has been found that the cables do not satisfy requirements of qualification set for the new generation of NPP by „The European Utility Requirements for LWR Nuclear Power Plants”, because content of several elements exceeded the maximal impurity levels. INAA proved to be a method of choice for elemental characterization of polymer materials of electrical cables as part of their qualification for use in NPP. Instrumentální neutronová aktivační analýza (INAA) byla použita k prvkové charakterizaci jednotlivých součástí elektrických kabelů v současnoti používaných v bezpečnostních systémech jaderných elektráren (JE). Analýzou byla získána informace o obsazích 35 prvků. Bylo zjištěno, že kabely nesplňují požadavky na kvalifikaci pro novou generaci JE podle „The European Utility Requirements for LWR Nuclear Power Plants”, protože obsahy několika prvků přesáhly maximální přípustné hodnoty pro nečistoty. Bylo prokázáno, že INAA je vhodnou metodou pro prvkovou charakterizaci polymerních materiálů elektrických kabelů při jejich kvalifikaci pro použití v JE.
Keywords:
instumental neutron activation analysis; polymer materials of electrical cables; impurity levels; qualification for use in nuclear power plants
Available at various institutes of the ASCR
Determination of elemental impurities in polymer materials of electrical cables of safety systems of nuclear power plants by neutron activation analysis
Instrumental neutron activation analysis (INAA) was employed for elemental characterization of individual components of electrical cables currently used in safety systems of nuclear power plants ...
Determination of iodine in biological materials by neutron activation analysis
Kučera, Jan
2012 - Czech
The advantages and disadvantages of various modes of neutron activation analysis (NAA), such as instrumental NAA (INAA), epithermal NAA (ENAA), and radiochemical NAA (RNAA) for iodine determination in biological materials, namely in food and diet samples are briefly reviewed. Examples are given of iodine determination in Asian diet samples by ENAA and RNAA. The accuracy of the results obtained was proved by analyses of numerous US NIST reference materials (RMs) of biological origin. Jsou vyhodnoceny výhody a nevýhody různých postupů neutronové aktivační analýzy (NAA), zejména instrumentální NAA (INAA), epithermální NAA (ENAA) a radiochemické NAA (RNAA) pro stanovení jódu v biologických materiálech, zejména ve vzorcích potravin a stravy. Jsou uvedeny příklady stanovení jódu ve vzorcích stravy z Asie metodami ENAA a RNAA. Správnost výsledků byla potvrzena analýzou četných biologických referenčních materiálů amerického NIST.
Keywords:
Iodine; neutron activation analysis; food; diet
Available at various institutes of the ASCR
Determination of iodine in biological materials by neutron activation analysis
The advantages and disadvantages of various modes of neutron activation analysis (NAA), such as instrumental NAA (INAA), epithermal NAA (ENAA), and radiochemical NAA (RNAA) for iodine determination in ...
Use of calculation of 14CO2 volume activity for reconstruction of radiocarbon content changes in atmosphere
Světlík, Ivo; Fejgl, M.; Turek, Karel; Pachnerová Brabcová, Kateřina; Tomášková, Lenka
2012 - Czech
Atmospheric 14CO2 provides valuable information for better specification of carbon transport in nature. Radioactive 14C allows calculating some data related to the residence time of carbon in natural sinks as the atmosphere, oceans and biota. The work presents the estimation of 14CO2 content temporal changes in the atmosphere using the radiocarbon calibration curve IntCal09 and data about CO2 concentration during last 50 thousands years. Cenné údaje pro upřesnění parametrů transportu uhlíku v přírodě poskytuje atmosférický 14CO2. Radioaktivní 14C umožňuje lépe vyčíslit některé údaje spojené s dobou zdržení uhlíku v jeho přirozených zásobnících nebo s rychlostí toku uhlíku mezi jednotlivými přírodními složkami jako jsou ovzduší, oceány a biota. Obsahem práce je odhad změn obsahu 14CO2 v atmosféře s využitím radiouhlíkové kalibrační křivky IntCal09 a údajů o koncentracích CO2 v ovzduší v průběhu posledních 50 tisíc let.
Keywords:
Radiocarbon; 14CO2; volume activity; atmosphere; temporal changes
Available at various institutes of the ASCR
Use of calculation of 14CO2 volume activity for reconstruction of radiocarbon content changes in atmosphere
Atmospheric 14CO2 provides valuable information for better specification of carbon transport in nature. Radioactive 14C allows calculating some data related to the residence time of carbon in natural ...
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