Sándor Nagy | Eötvös Loránd University (original) (raw)

Papers by Sándor Nagy

Research paper thumbnail of Interpretation of apparent surface texture observed in the M�ssbauer spectra of some57Co-doped ferromagnetic metals

Structural Chemistry, 1991

ABSTRACT Cobalt-57-doped Fe, Co, and Ni sheets were studied by Mössbauer spectroscopy. The spectr... more ABSTRACT Cobalt-57-doped Fe, Co, and Ni sheets were studied by Mössbauer spectroscopy. The spectra indicated that the preferred direction of the effective magnetic field in Fe and Ni was parallel to the surface. With Co only little preference was observed. The observations are quantitatively explained by assuming that the closure domains may only show parallel to the local easy direction of magnetization, but otherwise tend to be as perpendicular to the normal vector of the surface as possible.

Research paper thumbnail of Multinomial distribution as the most likely distribution of the stoichiometric composition of stochastically formednmers

Journal of Radioanalytical and Nuclear Chemistry Articles, 1990

Multinomial distribution is presented as the most likely distribution of the stoiehic~ metric com... more Multinomial distribution is presented as the most likely distribution of the stoiehic~ metric composition of stochastically formed nmers. The term rimer is used in a wide sense, meaning not only the usual species in polymer chemistry, but molecules or a well defined set of neighbouring atoms in a crystal lattice as well. As a practical example the authors present the statistica/ interpretation of the M6ssbauer spectra of ferromagnetic FeCrNi alloys. The problem discussed may also serve as a model calculation for courses on statistical thermodynamics.

Research paper thumbnail of SCA window optimization in Mössbauer spectroscopy: The case of constant background

Journal of Radioanalytical and Nuclear Chemistry Letters, 1989

Research paper thumbnail of A Mössbauer Study of Me Interaction Between Α-Ion and Aluminophosphate and Alumino-Chromo-Phosphate Adhesives

Le Journal de Physique Colloques, 1980

Research paper thumbnail of Mössbauer and NMR study of novel Tin(IV)-lactames

Hyperfine Interactions, 2012

N-tributylstannylated 2-pyrrolidinone was reacted with tributyltin triflate in different molar ra... more N-tributylstannylated 2-pyrrolidinone was reacted with tributyltin triflate in different molar ratios and the complex formation monitored using 1 H-NMR, 13 C-NMR and 119 Sn Mössbauer spectroscopy. Comparing the carbon NMR and tin Mössbauer results, a reaction scheme is suggested for the complexation which assumes the formation of a simultaneously O-and N-tributylstannylated pyrrolidinone cation. The formation of the only O-stannylated pyrrolidinone is also assumed to account for the non-constant Mössbauer parameters of the two tin environments in the distannylated pyrrolidinone cation when the ratio of tributyltin triflate is increased in the reaction. Keywords Tin(IV) lactames • 119 Sn Mössbauer spectroscopy • NMR

Research paper thumbnail of High-Temperature Superconductors and Related Compounds Studied by Mössbauer Spectroscopy

Active and Passive Electronic Components, 1993

57Fe,119Sn, and151Eu Mössbauer spectroscopy was used to study the chemical structure, phonon mode... more 57Fe,119Sn, and151Eu Mössbauer spectroscopy was used to study the chemical structure, phonon mode changes, and low-temperature phase transformation around the Tcas well as suppression of superconductivity in high-temperature superconductors and related compounds. Anomalous temperature-dependent changes in the total57Fe spectral area fraction and in the Mössbauer line shift were simultaneously found around the Tcin a EuBa2(Cu0.9957Fe0.01)3O7-dsuperconductor. These anomalous changes were attributed to phonon softening and low-temperature phase transformation occurring around the superconducting transition. Significant differences were observed between the57Fe Mössbauer spectra of superconducting EuBa2(Cu0.9957Fe0.01)3O7-dand the isostructural non-superconducting PrBa2(Cu0.9957Fe0.01)3O7-d. The differences were interpreted in connection with the suppression of superconductivity (by hole filling or hybridization of Pr, Cu and O states) in the Pr-containing compound. The unusually high i...

Research paper thumbnail of Radiochemistry and radiopharmaceutical chemistry in life sciences

Research paper thumbnail of Instrumentation, separation techniques, environmental issues

Research paper thumbnail of Structural investigation of the EuBa2Cu3O7-δ high TC superconductor by 151Eu, 119Sn, 57Fe and 57Co Mössbauer spectroscopy

Spectrochimica Acta Part A: Molecular Spectroscopy

Research paper thumbnail of Mössbauer study of the effects of annealing on tempered tool steel

Acta Metallurgica, 1983

ABSTRACT

Research paper thumbnail of Handbook of Nuclear Chemistry

Research paper thumbnail of High-Tc superconductors studied by57Co,57Fe,119Sn, and151Eu m�ssbauer spectroscopy

Structural Chemistry, 1991

Research paper thumbnail of Method for the simultaneous characterization of texture, orientation of electric field gradient, and/or magnetic field from the57Fe/57Co M�ssbauer spectrum of pellets having a cylindrical texture typical of YBa2Cu3O7?x superconductors

Structural Chemistry, 1990

A method using Mössbauer spectroscopy has been developed for estimating the degree of cylindrical... more A method using Mössbauer spectroscopy has been developed for estimating the degree of cylindrical texture in pellets of materials exemplified by the superconductor YBa 2 Cu 3 O 7-x. The procedure can also be used to determine unambiguously the sign and orientation ...

Research paper thumbnail of Mössbauer studies on high temperature superconductors

Hyperfine Interactions, 1994

Research paper thumbnail of Nuclear Methods in Mineralogy and Geology, Techniques and Applications

Clays and Clay Minerals, 1999

Research paper thumbnail of Determination of Retained Austenite in Steels Alloyed with Carbide Formers

Le Journal de Physique Colloques, 1979

RBsum6.-A parti: de la spectrom6trie Mijssbauer, on propose une methode pour determiner quantitat... more RBsum6.-A parti: de la spectrom6trie Mijssbauer, on propose une methode pour determiner quantitativement le taux d'austsnite retenu dans des aciers allies avec des elements carburogznes. On Blimine ainsi l'effet parasite des carbures paramagnetiques contenant du fer, 1 l'aide de procSd6s auxiliaires tels que traitements thermiques et analyse chimique. La methode semble appropriee pour l'examen de la formation, la transformation et la stabilisation de l'austenite. Abstract.-A method based upon Miissbauer spectroscopy is proposed for the quantitative determination of the retained austenite in steels alloyed with carbide forming elements. By means of this method, the disturbing effect of the paramagnetic carbides containing iron can be eliminated. The proposed method makes use of some supplementary procedures as for example appropriate heat treatments and chemical analysis. The method seems'to be suitable for the examination of formation, transformation and stabilization of austenite.

Research paper thumbnail of Subatomic Particles , Nuclear Structure and Stability

This chapter provides elementary introduction to the Standard Model of fundamental particles and ... more This chapter provides elementary introduction to the Standard Model of fundamental particles and interactions to serve with background for the Theme Radiochemistry and Nuclear Chemistry (RC&NC). It also illustrates the stability and instability of the nucleus by presenting the systematics of stable nuclei as well as by explaining the RADIOCHEMISTRY AND NUCLEAR CHEMISTRY-Vol. II-Subatomic Particles, Nuclear Structure and Stability-Sándor Nagy ©Encyclopedia of Life Support Systems (EOLSS) possible ways of reaching greater stability. Nuclear models are also explained in simple terms.

Research paper thumbnail of Method for the simultaneous characterization of texture, orientation of electric field gradient, and/or magnetic field from the 57 Fe/ 57 Co Mössbauer spectrum of pellets having a cylindrical texture typical of YBa 2 Cu 3 O 7−x superconductors

Structural Chemistry, 1990

A method using Mössbauer spectroscopy has been developed for estimating the degree of cylindrical... more A method using Mössbauer spectroscopy has been developed for estimating the degree of cylindrical texture in pellets of materials exemplified by the superconductor YBa2Cu3O7−x.The procedure can also be used to determine unambiguously the sign and orientation of the electric field gradient of a nonmagnetic species coexisting with a magnetically ordered one (or coexisting with another nonmagnetic species for which the sign and the orientation of the electric field gradient are known).

Research paper thumbnail of Mössbauer investigation of iron in aluminium—I. Al-Fe samples

Acta Metallurgica, 1987

ABSTRACT

Research paper thumbnail of A mossbauer study of iron impurity in some aluminium samples

Scripta Metallurgica, 1982

Research paper thumbnail of Interpretation of apparent surface texture observed in the M�ssbauer spectra of some57Co-doped ferromagnetic metals

Structural Chemistry, 1991

ABSTRACT Cobalt-57-doped Fe, Co, and Ni sheets were studied by Mössbauer spectroscopy. The spectr... more ABSTRACT Cobalt-57-doped Fe, Co, and Ni sheets were studied by Mössbauer spectroscopy. The spectra indicated that the preferred direction of the effective magnetic field in Fe and Ni was parallel to the surface. With Co only little preference was observed. The observations are quantitatively explained by assuming that the closure domains may only show parallel to the local easy direction of magnetization, but otherwise tend to be as perpendicular to the normal vector of the surface as possible.

Research paper thumbnail of Multinomial distribution as the most likely distribution of the stoichiometric composition of stochastically formednmers

Journal of Radioanalytical and Nuclear Chemistry Articles, 1990

Multinomial distribution is presented as the most likely distribution of the stoiehic~ metric com... more Multinomial distribution is presented as the most likely distribution of the stoiehic~ metric composition of stochastically formed nmers. The term rimer is used in a wide sense, meaning not only the usual species in polymer chemistry, but molecules or a well defined set of neighbouring atoms in a crystal lattice as well. As a practical example the authors present the statistica/ interpretation of the M6ssbauer spectra of ferromagnetic FeCrNi alloys. The problem discussed may also serve as a model calculation for courses on statistical thermodynamics.

Research paper thumbnail of SCA window optimization in Mössbauer spectroscopy: The case of constant background

Journal of Radioanalytical and Nuclear Chemistry Letters, 1989

Research paper thumbnail of A Mössbauer Study of Me Interaction Between Α-Ion and Aluminophosphate and Alumino-Chromo-Phosphate Adhesives

Le Journal de Physique Colloques, 1980

Research paper thumbnail of Mössbauer and NMR study of novel Tin(IV)-lactames

Hyperfine Interactions, 2012

N-tributylstannylated 2-pyrrolidinone was reacted with tributyltin triflate in different molar ra... more N-tributylstannylated 2-pyrrolidinone was reacted with tributyltin triflate in different molar ratios and the complex formation monitored using 1 H-NMR, 13 C-NMR and 119 Sn Mössbauer spectroscopy. Comparing the carbon NMR and tin Mössbauer results, a reaction scheme is suggested for the complexation which assumes the formation of a simultaneously O-and N-tributylstannylated pyrrolidinone cation. The formation of the only O-stannylated pyrrolidinone is also assumed to account for the non-constant Mössbauer parameters of the two tin environments in the distannylated pyrrolidinone cation when the ratio of tributyltin triflate is increased in the reaction. Keywords Tin(IV) lactames • 119 Sn Mössbauer spectroscopy • NMR

Research paper thumbnail of High-Temperature Superconductors and Related Compounds Studied by Mössbauer Spectroscopy

Active and Passive Electronic Components, 1993

57Fe,119Sn, and151Eu Mössbauer spectroscopy was used to study the chemical structure, phonon mode... more 57Fe,119Sn, and151Eu Mössbauer spectroscopy was used to study the chemical structure, phonon mode changes, and low-temperature phase transformation around the Tcas well as suppression of superconductivity in high-temperature superconductors and related compounds. Anomalous temperature-dependent changes in the total57Fe spectral area fraction and in the Mössbauer line shift were simultaneously found around the Tcin a EuBa2(Cu0.9957Fe0.01)3O7-dsuperconductor. These anomalous changes were attributed to phonon softening and low-temperature phase transformation occurring around the superconducting transition. Significant differences were observed between the57Fe Mössbauer spectra of superconducting EuBa2(Cu0.9957Fe0.01)3O7-dand the isostructural non-superconducting PrBa2(Cu0.9957Fe0.01)3O7-d. The differences were interpreted in connection with the suppression of superconductivity (by hole filling or hybridization of Pr, Cu and O states) in the Pr-containing compound. The unusually high i...

Research paper thumbnail of Radiochemistry and radiopharmaceutical chemistry in life sciences

Research paper thumbnail of Instrumentation, separation techniques, environmental issues

Research paper thumbnail of Structural investigation of the EuBa2Cu3O7-δ high TC superconductor by 151Eu, 119Sn, 57Fe and 57Co Mössbauer spectroscopy

Spectrochimica Acta Part A: Molecular Spectroscopy

Research paper thumbnail of Mössbauer study of the effects of annealing on tempered tool steel

Acta Metallurgica, 1983

ABSTRACT

Research paper thumbnail of Handbook of Nuclear Chemistry

Research paper thumbnail of High-Tc superconductors studied by57Co,57Fe,119Sn, and151Eu m�ssbauer spectroscopy

Structural Chemistry, 1991

Research paper thumbnail of Method for the simultaneous characterization of texture, orientation of electric field gradient, and/or magnetic field from the57Fe/57Co M�ssbauer spectrum of pellets having a cylindrical texture typical of YBa2Cu3O7?x superconductors

Structural Chemistry, 1990

A method using Mössbauer spectroscopy has been developed for estimating the degree of cylindrical... more A method using Mössbauer spectroscopy has been developed for estimating the degree of cylindrical texture in pellets of materials exemplified by the superconductor YBa 2 Cu 3 O 7-x. The procedure can also be used to determine unambiguously the sign and orientation ...

Research paper thumbnail of Mössbauer studies on high temperature superconductors

Hyperfine Interactions, 1994

Research paper thumbnail of Nuclear Methods in Mineralogy and Geology, Techniques and Applications

Clays and Clay Minerals, 1999

Research paper thumbnail of Determination of Retained Austenite in Steels Alloyed with Carbide Formers

Le Journal de Physique Colloques, 1979

RBsum6.-A parti: de la spectrom6trie Mijssbauer, on propose une methode pour determiner quantitat... more RBsum6.-A parti: de la spectrom6trie Mijssbauer, on propose une methode pour determiner quantitativement le taux d'austsnite retenu dans des aciers allies avec des elements carburogznes. On Blimine ainsi l'effet parasite des carbures paramagnetiques contenant du fer, 1 l'aide de procSd6s auxiliaires tels que traitements thermiques et analyse chimique. La methode semble appropriee pour l'examen de la formation, la transformation et la stabilisation de l'austenite. Abstract.-A method based upon Miissbauer spectroscopy is proposed for the quantitative determination of the retained austenite in steels alloyed with carbide forming elements. By means of this method, the disturbing effect of the paramagnetic carbides containing iron can be eliminated. The proposed method makes use of some supplementary procedures as for example appropriate heat treatments and chemical analysis. The method seems'to be suitable for the examination of formation, transformation and stabilization of austenite.

Research paper thumbnail of Subatomic Particles , Nuclear Structure and Stability

This chapter provides elementary introduction to the Standard Model of fundamental particles and ... more This chapter provides elementary introduction to the Standard Model of fundamental particles and interactions to serve with background for the Theme Radiochemistry and Nuclear Chemistry (RC&NC). It also illustrates the stability and instability of the nucleus by presenting the systematics of stable nuclei as well as by explaining the RADIOCHEMISTRY AND NUCLEAR CHEMISTRY-Vol. II-Subatomic Particles, Nuclear Structure and Stability-Sándor Nagy ©Encyclopedia of Life Support Systems (EOLSS) possible ways of reaching greater stability. Nuclear models are also explained in simple terms.

Research paper thumbnail of Method for the simultaneous characterization of texture, orientation of electric field gradient, and/or magnetic field from the 57 Fe/ 57 Co Mössbauer spectrum of pellets having a cylindrical texture typical of YBa 2 Cu 3 O 7−x superconductors

Structural Chemistry, 1990

A method using Mössbauer spectroscopy has been developed for estimating the degree of cylindrical... more A method using Mössbauer spectroscopy has been developed for estimating the degree of cylindrical texture in pellets of materials exemplified by the superconductor YBa2Cu3O7−x.The procedure can also be used to determine unambiguously the sign and orientation of the electric field gradient of a nonmagnetic species coexisting with a magnetically ordered one (or coexisting with another nonmagnetic species for which the sign and the orientation of the electric field gradient are known).

Research paper thumbnail of Mössbauer investigation of iron in aluminium—I. Al-Fe samples

Acta Metallurgica, 1987

ABSTRACT

Research paper thumbnail of A mossbauer study of iron impurity in some aluminium samples

Scripta Metallurgica, 1982