Search results

1

Magnetic Properties of the RbNd(WO₄)₂ Single Crystal

100%

Borowiec M., Zubov E., Zajarniuk T., Barański M.

Acta Physica Polonica A

|

2016

|

vol. 129

|

issue 3

359-361

EN

The magnetic investigations as a function of the temperature and magnetic field for the rubidium neodymium double tungstate RbNd(WO₄)₂ single crystal have been performed. The magnetization was measured in the temperature range from 4.2 to 100 K and for the magnetic field up to 1.5 T. The crystal field and exchange parameters were found.

2

Magnetoelastic and Optical Studies of Low Temperature Magnetic Relaxation in Rare-Earth Orthoaluminates with Ising Ions

88%

Krynetskii I., Popkov A., Borowiec M., Szymczak H., Zayarnyuk T.

Acta Physica Polonica A

|

2000

|

vol. 97

|

issue 5

889-892

EN

The new class of magnetic materials with low temperature magnetic relaxation was studied. It was evidenced that the crystal DyAlO_{3} with antiferromagnetically ordered high anisotropy rare-earth ions showed an exponential magnetic relaxation. For the first time low temperature magnetic relaxation was investigated by means of magnetostriction and rare-earth optical absorption spectra instead of standard magnetization measurements. The possible mesoscopic nature of tunneling process was suggested.

3

Photoconductivity of Bi_{12}Ti_{1-x}Pb_{x}O_{20} Single Crystal

76%

Borowiec M., Kozankiewicz B., Szymczak H., Żmija J., Majchrowski A., Załęski M., Zayarnyuk T.

|

vol. 96

|

issue 6

785-792

EN

Single crystals of mixed sillenites Bi_{12}Ti_{1-x}Pb_{x}O_{20} were grown using the top seeded solution growth method. The pulse illumination was used to study the phototransport properties of these crystals. It was evidenced that the illumination changed the photoconducting properties by 4-5 orders of magnitude comparing with previously studied Bi_{12}MeO_{20}, where Me = Ge, Si, Ti. The performed experiments indicate on the photogeneration of metallic grains in the insulating matrix of Bi_{12}Ti_{1-x}Pb_{x}O_{20}. Correlations between photochromism and photoconductivity was established.

4

Low-Temperature Structural Phase Transition in Monoclinic RbDy(WO_{4})_{2} Crystal

76%

Borowiec M., Dyakonov V., Kamenev V., Nabiałek A., Prokhorov A., Szymczak H., Załęski M.

Acta Physica Polonica A

|

1998

|

vol. 94

|

issue 1

71-77

EN

The ESR spectrum of Dy^{3+} ion in the low-symmetry RbDy(WO_{4})_{2} crystal has been studied in the temperature region of T=4.2 ÷ 30K. The ESR linewidth was found to increase from 130 mT up to the maximum value of 190 mT at T=9K and then to decrease down to 150 mT at 4.2K. The components of the g-tensor change considerably without change of their spatial orientation in the temperature range from 12K to 7 K: g_{z}=2.5, g_{x}≈0, g_{y}=1.41 at T>12 K; g_{z}=1.53, g_{x}≈0, g_{y}=1.2 at T<7K. The observed λ-shaped behaviour of absorption linewidth and the decrease in the g-factor are assumed to be due to the low-temperature structural phase transition (T_{SPT}≈9 K). The width of the transition area is of about 5K. It is suggested that the symmetry of high- and low-temperature phases is identical.

5

A protective role of HLA-DR locus in patients with various clinical types of alopecia areata

76%

Broniarczyk-Dyla G., Prusinska-Bratos M., Dubla-Berner M., Arkuszewska C., Borowiec M., Kowalski M. L., Woszczek G.

Archivum Immunologiae et Therapiae Experimentalis

|

2002

|

vol. 50

|

issue 5

333-336

EN

One of genetic factors associated with the development of alopecia areata (AA) is HLA locus. The study comprised 52 patients with AA, aged 10 to 64 years. The frequences of HLA-DR B alleles in patients and controls were compared. The control group comprised 152 healthy persons. Familiar occurrence of alopecia areata was seen in 7 cases (13.5%). Significantly lower frequency of HLA-DRB1*03 was observed in patients with AA in comparison to control group. In all patients with AA alleles HLA-DRB1*15/*16 occurred more frequently than in control group, but it was not significant after correction. In the group of patients with more severe form of alopecia areata (AAT/U) there was no significant difference in HLA- DR alleles distribution

6

Local Magnetic and Electronic Properties of the A2FeM'O6 (A = Ba, Sr, Ca, M' = Mo, Re) Double Perovskites

64%

Zając D., Sikora M., Prochazka V., Borowiec M., Stępień J., Kapusta C., Riedi P., Marquina C., De Teresa J., Ibarra M.

Acta Physica Polonica A

|

2007

|

vol. 111

|

issue 6

797-820

EN

The results of a combined NMR, X-ray absorption spectroscopy and X-ray magnetic cirrcular dichroism study of the AA'FeMoO_6 and AA'FeReO_6 double perovskites are presented. They revealed a dependence of electronic and magnetic properties, including a d-electron transfer between Fe and Mo sites, on the structural tolerance factor. The maximum value of the 4d Mo electron occupation and the corresponding Mo moment is obtained for the tolerance factor of unity. This corresponds to the maximum strength of the magnetic interaction and, respectively, to the Curie temperature. The dominant T^{5/2} type temperature dependence of the Mo hyperfine field reveals the half-metallicity of the AA'FeMoO_6 compounds. Antisite defects and antiphase boundaries have been identified in NMR measurements and the strength of their magnetic coupling have been determined. A considerable orbital contribution to the Re and Fe magnetic moments were found in the NMR and X-MCD measurements on the AA'FeReO_6 compounds. Its magnitude decreases with increasing structural tolerance factor and is correlated with their magnetic anisotropy.

7

Crystalline Structure of Potassium Holmium Double Tungstate

46%

Borowiec M., Dyakonov V., Woźniak K., Dobrzycki Ł., Majchrowski A., Michalski E., Zubov E., Khatsko E., Zayarnyuk T., Szewczyk A., Gutowska M., Rykova A., Barański M., Domukhovski V., Shtyrkhunova V., Iwanowski P., Żmija J., Szymczak H.

Acta Physica Polonica A

|

2011

|

vol. 119

|

issue 6

835-837

EN

The potassium holmium double tungstate was prepared by using top seeded solution growth technique. Structural investigations have been performed at room temperature. The KHo(WO_4)_2 single crystal belongs to the monoclinic space group C2/c with the unit-cell parameters: a = 10.624(2) Å, b = 10.352(2) Å, c = 7.5434(15) Å, β = 130.78(3)^{o}, and Z = 4. The atomic coordinates, isotropic and anisotropic displacement parameters and interionic distances for the studied structure were determined.

Refine search results

Magnetic Properties of the RbNd(WO₄)₂ Single Crystal

Magnetoelastic and Optical Studies of Low Temperature Magnetic Relaxation in Rare-Earth Orthoaluminates with Ising Ions

Photoconductivity of Bi_{12}Ti_{1-x}Pb_{x}O_{20} Single Crystal

Low-Temperature Structural Phase Transition in Monoclinic RbDy(WO_{4})_{2} Crystal

A protective role of HLA-DR locus in patients with various clinical types of alopecia areata

Local Magnetic and Electronic Properties of the A2FeM'O6 (A = Ba, Sr, Ca, M' = Mo, Re) Double Perovskites

Crystalline Structure of Potassium Holmium Double Tungstate