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1
Content available Mössbauer spectroscopy study of 60P2O5-40Fe2O3 glass
Stoch P., Ciecińska M., Zachariasz P., Suwalski J., Górski L., Wójcik T.
Nukleonika
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2013
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Vol. 58, No. 1
63-66
EN
A 57Fe Mössbauer spectroscopy study is presented. The main goal of the research was to investigate the structural information of the glass-like the coordination numbers and redox ratio of the iron. Most of the iron, about 80%, is present in the glass as Fe3+, which is composed of tetrahedral (57%) and octahedral (23%) coordinated iron. The rest of the iron, about 20%, is in the oxidation state Fe2+. This iron could be mostly present as VIFe2+, but five-fold coordinated iron is also possible. Finally, the structural model of the synthesized 60P2O5-40Fe2O3 glass was proposed.
2
Content available Hyperfine interactions in Tb0.27-xYxDy0.73Fe2 compounds at 295 K
Krawczyk A., Zwoźniak A., Guzdek P., Stoch P., Zachariasz P., Suwalski J., Pszczoła J.
Nukleonika
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2013
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Vol. 58, No. 1
133-135
EN
This paper concerns the synthesis of yttrium-dilute Tb0.27-xYxDy0.73Fe2 intermetallic series with a borderline compound Tb0.27Dy0.73Fe2 known as Terfenol-D by arc melting, XRD analysis and 57Fe Mössbauer effect studies at 295 K. XRD analysis (295 K) shows that all samples crystallize in a cubic, Fd3m, MgCu2-type structure. The lattice parameter increases along with yttrium content. Mössbauer effect spectra for the Tb0.27-xYxDy0.73Fe2 series collected at 295 K consist of two subspectra due to easy direction of magnetization <111>. Hyperfine interaction parameters: isomer shift, magnetic hyperfine field and a quadrupole splitting were obtained from the fitting procedure of the spectra.
3
Content available Hyperfine interactions in Dy(Co0.4-xNixFe0.6)2 compounds at 295 K
Zwoźniak A., Krawczyk A., Stoch P., Guzdek P., Zachariasz P., Suwalski J., Pszczoła J.
Nukleonika
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2013
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Vol. 58, No. 1
179-181
EN
57Fe Mössbauer effect studies were performed for the cubic C15, Fd3m, MgCu2-type Dy(Co0.4-xNixFe0.6)2 intermetallics. Hyperfine interaction parameters : isomer shift, magnetic hyperfine field and quadrupole interaction parameter were obtained from the fitting procedure of the collected 57Fe Mössbauer effect spectra. As a result of Co/Ni substitution, a Slater-Pauling type curve for the average magnetic hyperfine field vs. Ni content in the Dy(Co0.4-xNixFe0.6)2 series is observed.
4
Content available Hyperfine interactions in Ho(Fe1-xCox)2 compounds at 295 K
Bednarski M., Stoch P., Bodnar W., Zachariasz P., Pszczoła J., Suwalski J.
Nukleonika
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2010
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Vol. 55, No. 3
279-284
EN
Synthesis of Ho(Fe1–xCox)2 intermetallic compounds, studies of their crystal structure and 57Fe Mössbauer effect analysis were carried out at 295 K. X-ray measurements evidence a pure cubic Fd3m, C15, MgCu2-type Laves phase. The unit cell parameter decreases non-linearly with composition parameter x. Mössbauer effect spectra for the Ho(Fe1–xCox)2 series were composed of a number of locally originated subspectra due to random Fe/Co nearest neighbourhoods. Hyperfine interaction parameters, i.e. isomer shift, the magnetic hyperfine field and a quadrupole interaction parameter were determined from the fitting procedure of the spectra, for both the individual nearest neighbourhoods, and for the sample as bulk. As a consequence of Fe/Co substitution a Slater-Pauling type curve for the average magnetic hyperfine field vs. x is observed. The correlation between the local magnetic hyperfine fields and the average magnetic hyperfine fields is related to weak and strong ferromagnetism of the transition metal sublattice.
5
Content available Hyperfine interactions in Tb0.27Dy0.73(Fe1–xCox)2 compounds at 77 K
Bodnar W., Szklarska-Łukasik M., Stoch P., Zachariasz P., Pszczoła J., Suwalski J.
Nukleonika
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2009
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Vol. 54, No. 4
227-232
EN
The synthesis of materials, crystal structure and 57Fe Mössbauer effect studies at 77 K were performed for intermetallics Tb0.27Dy0.73(Fe1–xCox)2. The starting compound Tb0.27Dy0.73Fe2 of this Fe/Co substituted series is known as Terfenol-D. XRD measurements evidence a pure cubic Laves phase C15, MgCu2-type. The determined unit cell parameter decreases across the series. Co substitution introduces a local area, in the subnanoscale, with random Fe/Co neighbourhoods of the 57Fe atoms. Mössbauer effect spectra for the Tb0.27Dy0.73(Fe1–xCox)2 series collected at 77 K consist of a number of locally originated subspectra due to random composition of Fe and Co atoms in the nearest neighbourhood. Hyperfine interaction parameters: isomer shift, magnetic hyperfine field and a quadrupole interaction parameter were obtained from the fitting procedure of the spectra, both for the local area and for the sample as bulk. As a result of Fe/Co substitution, a Slater-Pauling type curve for the average magnetic hyperfine field vs. Co content in the Tb0.27Dy0.73(Fe1–xCox)2 series is observed. It is found that the magnetic hyperfine fields corresponding to the local area sorted out against Co contribution in the Fe/Co neighbourhoods also create a dependence similar to the Slater-Pauling type curve.
6
Content available Mössbauer effect studies of Dy(Fe0.4-xNixCo0.6)2
Jabłońska A., Suwalski J., Stoch P., Pszczoła J., Guzdek P., Szamański P., Pańta A.
Nukleonika
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2007
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Vol. 52, supl. 1
55-58
EN
A consequence of the Fe/Ni substitution in the Dy(Fe0.4Co0.6)2 compound was studied in the present paper. For this purpose the synthesis and X-ray analysis (295 K) of the Dy(Fe0.4 xNixCo0.6)2 series were performed. The cubic, MgCu2-type, Fd3m crystal structure was observed across the series. 57Fe Mössbauer effect spectra for the series were collected at 77 K. The obtained crystallographic data and the hyperfine interaction parameters are presented. The magnetic hyperfine fields form a separate branch of the Slater-Pauling curve known for the Dy(Mn1 xFex)2 and Dy(Fe1 xCox)2 series. The data are qualitatively related to the Stoner model.
7
Content available Investigation of low temperature diffusion of carbon in martensite by Mössbauer spectroscopy and X-ray diffraction
Jabłońska A., Dąbrowski L., Suwalski J., Neov S.
Nukleonika
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2006
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Vol. 51, nr 2
101-104
EN
Martensite containing 0.87 wt.% carbon was studied by Mössbauer spectroscopy at temperatures, T = 10, 15, 25, 40 and 78 K and by X-ray diffraction at T = 78 K in the course of 35 days. Samples in the form of 30 mm thick foil of pure carbon martensite with enhanced tetragonality were synthesized applying non-standard technology. The measured by X-rays (c/a - 1) ratio varies within the limits 0.044-0.055 by pulsations with a period of few hours. According to Kurdimov’s model any changes in tetragonality of martensite are fully related to the passage of carbon atoms from Oc to Oa and Ob octahedral sites or vice versa. Pulsations of the central and satellite sextets were observed by Mössbauer spectroscopy. In accordance with the conventional interpretation of satellites, these pulsations result from different spatial distribution of carbon around the Fe atoms in the diffusion process. The data of (c/a - 1) pulsations were used to determine the diffusion coefficient below 78 K. The measured diffusion coefficient of carbon in a-iron below 78 K contradicts the classical approach to the observed temperature dependence. As the temperature is lowered below 78 K, the diffusion constant approaches the nearly temperature-independent value. The low temperature branch is apparently characteristic of a quantum mechanical process dominated by tunnelling in the ground state.
8
Content available remote System sprężonego powietrza zakładu farmaceutycznego. Studium projektowe
Mikołajczak J. K., Suwalski J.
Pneumatyka
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2004
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nr 4
25-27
PL
Zagadnienia związane z projektowaniem przemysłowych systemów sprężonego powietrza od wielu lat znajdują się w zakresie działalności Katedry Klimatyzacji i Ciepłownictwa Politechniki Wrocławskiej. Jej interesującym przykładem jest praca magisterska pod tytułem "System sprężonego powietrza zakładu farmaceutycznego" wykonana w roku akademickim 2003 - 2004.
9
Content available Mössbauer effect studies of Dy(Mn0.4-xAlxFe0.6)2 intermetallics
Stoch P., Pszczoła J., Guzdek P., Jabłońska A., Suwalski J., Dąbrowski L., Pańta A.
Nukleonika
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2004
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Vol. 49,suppl.3
23-25
EN
Both 3d subbands in the Dy(Mn0.4Fe0.6)2 compound are filled up only partially with 3d electrons. So, it was interesting to study the consequence of Mn/Al substitution in the Dy(Mn0.4 xAlxFe0.6)2 series. The cubic, MgCu2-type, Fd3m crystal structure was observed across the series. However, for x = 0.35 and 0.40 a stoichiometric admixture of the hexagonal, MgZn2-type, P63/mmc structure was evidenced. Mössbauer effect measurements at 57Fe nuclei were performed at 77 K. The magnetic hyperfine field decreases vs. the aluminium content x. This dependence is related to the possible 3d-electron band structure.
10
Content available Mössbauer effect studies of Dy(Fe0.7-xNixCo0.3)2 intermetallics
Jabłońska A., Suwalski J., Pszczoła J., Guzdek P., Stoch P., Pańta A.
Nukleonika
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2004
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Vol. 49,suppl.3
85-88
EN
Abstract A consequence of the Fe/Ni substitution in the series of Dy(Fe0.7 xNixCo0.3)2 was studied in the presented paper. The synthesis and X-ray analysis (300 K) of the Dy(Fe0.7 xNixCo0.3)2 system were performed. The cubic, MgCu2-type, Fd3m crystal structure was evidenced for this solid solution. 57Fe Mössbauer effect measurements for the system were carried out at 77 K. The obtained crystallographic lattice parameters and the hyperfine interaction data are presented. The magnetic hyperfine field values form a separate branch of the Slater-Pauling curve situated above the branch corresponding to the Dy(Fe1 xCox)2 intermetallics.
11
O metodologicznych aspektach ekspertyz budowlanych
Czapliński K., Suwalski J.
Inżynieria i Budownictwo
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2004
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R. 60, nr 7
369-373
PL
Omówiono ogólne zasady wykonywania ekspertyz budowlanych. Zwrócono uwagę na problemy, które powinny być analizowane, a także na metodykę pracy eksperta.
EN
The general principles concerning building survey's compilations are given. Attention has been paid to problems which should be analysed and to methodical work of the expert.
12
Content available Structural and Mössbauer effect studies of Dy(Fe0.4Co0.6-x Alx)2 intermetallics
Stoch P., Pszczoła J., Suwalski J., Pańta A.
Nukleonika
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2003
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Vol. 48,suppl.1
75-77
EN
The magnetic hyperfine fields observed at the 57Fe nuclei (77 K) in the Dy(Mn1-xFex)2 and Dy(Fe1-xCox)2 intermetallics form a Slater-Pauling curve. In order to study the effect of cobalt atoms on crystal structure and hyperfine interactions, the new Co/Al substituted series Dy(Fe0.4Co0.6-xAlx)2 was prepared and data of X-ray powder analysis are presented (300 K). From the 57Fe Mössbauer measurements at 77 K the hyperfine parameters were obtained. The magnetic hyperfine fields form a branch of the Slater-Pauling curve.
13
Content available Complexation of polyaniline with Lewis acids - a Mössbauer spectroscopy study
Bieńkowski K., Oddou J., Horner O., Kulszewicz-Bajer I., Genoud F., Suwalski J., Pron A.
Nukleonika
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2003
|
Vol. 48,suppl.1
3-7
EN
Doping with Lewis acid is a new method for improving solution processibility of conductive polyaniline. We report here detailed Mössbauer spectroscopy studies of polyaniline complexed with Lewis acids containing Mössbauer active nuclei, namely SnCl4 and FeCl3. Films of Lewis acid doped polyaniline cast from nitromethane solutions show stoichiometries of PANI(MeCln)1(CH3NO2)1 (where n = 3 or 4, Me denotes Sn or Fe and PANI denotes one aniline repeat unit), which means that both types of polyaniline nitrogens (imine and amine) participate in the complexation reaction, and one solvent molecule is introduced in the polymer matrix per one Lewis acid molecule. Mössbauer parameters of polyaniline doped with SnCl4 are consistent with hexacoordinated Sn(IV) in an environment of non-equivalent ligands. The spectrum of PANI doped with FeCl3 consists of two doublets with distinctly different Mössbauer parameters, which can be ascribed to two types of complexing sites (amine and imine nitrogens). From the temperature dependence of the isomer shift and the recoil free absorption, we have calculated the Mössbauer lattice temperature, ?m, as probed by both complexing sites, which are 83 K for amine and 126 K for imine sites.
14
Content available remote Specyfika remontu starych konstrukcji budowlanych i żelbetowych
Podolski B., Suwalski J., Wydra W.
Ochrona przed Korozją
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2001
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nr 3
67-69
PL
Remont konstrukcji betonowych i żelbetowych, pochodzących Z początków ich stosowania w budownictwie, podlega szczególnym uwarunkowaniom. Uwarunkowania te wynikają głównie ze stosowania w przeszłości materiałów o innej - najczęściej niższej - jakości oraz z innego niż obecnie kształtowania przekrojów i konstruowania zbrojenia. W artykule przedstawiono problemy projektowania oraz realizacji napraw i wzmocnień dawnych konstrukcji na przykładach wybranych obiektów.
EN
Refurbishment of old concrete structures set up before the 11 World War has to be performed in a special way. It is caused mainly by low quality construction materials used in those times, different shapes and sections of old structures as well as by different reinforcement design. Design, repair and structural reinforcement of old concrete structures have been presented and examples of structure refurbishment have been given.
15
Prawo budowlane, gospodarka a utrzymanie budynku
Czapliński K., Suwalski J., Zwierzchowska Z.
Prace Naukowe Instytutu Budownictwa Politechniki Wrocławskiej. Konferencje
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1998
|
Vol. 71, nr 24
39-43
PL
Zagadnienie prowadzenia odpowiednich zabiegów technicznych w aspekcie bezpiecznego użytkowania obiektów i zapobiegania awariom związane jest ściśle ze stanem właściwości tych obiektów. W referacie autorzy, na podstawie wybranych przykładów, zarysowują problem związany z realizacją postanowień ustawy Prawo budowlane w sprywatyzowanych i komunalnych budynkach mieszkalnych, wielorodzinnych. Autorzy zwracają też uwagę na wzrost zagrożenia, spowodowanego niewłaściwą eksploatacją i utrzymaniem obiektów, a wynikającego głównie z braku świadomości tego zagrożenia u ich zarządców, nowych właścicieli, jak też na trudności organizacyjne w skutecznym zapobieganiu temu zagrożeniu.
EN
Execution of suitable technical measures in order to attain the safe exploitation of building objects and to prevent their damages is a problem being closely connected with legal property state of these objects. On the ground of chosen examples the authors describe in this paper the problem bound with realization of building law provisions in private made and municipal apartment buildings for many families. The authors take also into cosideration the increase of damage hazard caused by improper exploitation and maintenance of the objects resulting mainly from the lack of consciousness of this hazard by their administrators or new proprietors and also from organization difficulties in effective prevention of these hazards.
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