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81.
Bohdan Andriyevsky Jan Suchanicz Christoph Cobet Aleksy Patryn Norbert Esser Boguslaw Kosturek 《Phase Transitions》2013,86(8):567-575
The pseudo dielectric function ?ε? (E) = ?ε 1? (E) + i?ε 2? (E) of sodium bismuth titanate Na0.5Bi0.5TiO3, has been obtained in the spectral range of electronic excitations (2–9.5 eV) by spectroscopic ellipsometry using the synchrotron radiation source BESSY II. The spectrum contains a broad absorption band at 4.2–4.5 eV. The temperature dependence in the range of 25–350°C is presented by the related susceptibilities ?χ 1? (T) and ?χ 2? (T) at 5 eV. A clear peculiarity in the temperature behavior of ?χ 1? (T) and ?χ 2? (T) between 180 and 320°C has been revealed and discussed. In this range an extremum-like temperature dependence of intensity of the light reflected from the sample surface, has been revealed and can be explained by the diffraction of light on the grid of the elastic domain structure of the sample. 相似文献
82.
83.
CZUPRYNSKI Boguslaw PACIOREK-SADOWSKA Joanna LISZKOWSKA Joanna 《中国化学》2006,24(12):1796-1799
Effect of tri(2-hydroxypropyl), tri(2-hydroxybutyl)and tri(hydroxythiodiethylene) borates (BT2HB, BT2HP and BTHET) on the thermal and heat properties of the rigid polyurethane-polyisocyanurate (PUR-PIR) foams was investigated: Increasing amounts of BT2HB and BT2HP in the foam composition, from 0.05 to 0.4 of chemical equivalent, caused increases in the softening point, the temperature of the first mass loss, the extrapolated tempera- ture of the main mass loss foam and temperature of the highest rate of the mass loss. In the case when BTHTE was added to the foam compositions, the lower increase in the mentioned above characteristic temperatures was observed as compared to those of standard foam (without borate added). 相似文献
84.
Boguslaw Von Bobraski 《Fresenius' Journal of Analytical Chemistry》1931,84(6-7):225-240
Ohne Zusammenfassung 相似文献
85.
Boguslaw Tomanek Lawrence Ryner David I. Hoult Piotr Kozlowski John K. Saunders 《Magnetic resonance imaging》1997,15(10):1199-1204
The theory and construction of a dual surface coil which provides good B1 homogeneity and sensitivity in a defined volume of interest is described. The probe comprises two coaxial rings, of different diameters and in different planes, which carry opposing currents of different values. Current in the second ring compensates for the roll-off of the B1 field associated with a single surface coil. Coupling between the rings and a third matching ring is by mutual inductance only. A comparison to a traditional surface coil with practical application to pig brain imaging at a field strength of 7 Tesla is shown. 相似文献
86.
Boguslaw Tomaszewski 《Journal of Functional Analysis》1984,55(1):63-67
It is shown, for n ? m ? 1, that there exist inner maps Φ: Bn → Bm with boundary values such that . where σn and σm are the Haar measures on ?Bn and ?Bm, respectively, and A ? Bn is an arbitrary Borel set. 相似文献
87.
Boguslaw Zegarliński 《Communications in Mathematical Physics》1986,107(3):411-429
We investigate the connections of the Gibbs measures, which appear in Euclidean Field Theory, and the corresponding partial differential equations of Classical Euclidean Field Theory. 相似文献
88.
Addition of Reformatsky reagents 1 to two azirines is reported. From 2-phényl-3,3-dimethyl azirine 2, aziridines esters 3 are obtained. 2-Phenyl-3-methyl azirine 4 gives aziridines esters 5 and diazepinones 6. Δ-3-Pyrrolinones or 5-methylene pyrrolidones are obtained from Grignard reagents and aziridines esters 3 and 5. The reaction mechanism is discussed; compounds 7,8,9,11 and 12 result from an aza-1-oxo-2-bicyclo-pentane (2,1,0) intermediate. 相似文献
89.
The main difficulty in micro-HPLC separation is the manipulation with the composition of the mobile phase (degassing of solvents and a slow establishment of equilibrium) but the problem of elution can be solved by temperature optimalization. The effect of temperature in micro-HPLC separation of the 16 polycyclic aromatic hydrocarbons (PAHs) (mixture SRM 1647 of the US EPA) has been studied using conventional C18 and new developed AP phase (an amide group localized in the hydrophobic ligands). All the investigations have been performed under isocratic conditions (binary hydroorganic mobile phase: acetonitrile/water). The results have shown that, in the case of AP phase, application of temperature gradient (from 298 to 303 K), enabled the attainment of complete 16 PAHs separation (especially of the first 4 solutes). 相似文献
90.
In situ dual-beam coincidence second harmonic generation was used to monitor spatially resolved dynamics at the Pt(111)/CO-saturated 0.1 M HClO4 interface. The results obtained showed that, for potential steps from 30 to about 870 mV vs RHE, the full electrooxidation of CO as evidenced from SHG occurred at different times for the two areas of the Pt(111) surface probed by the beams. On this basis, the diffusional rates of adsorbed CO cannot be assumed to be generally large enough as to render the entire surface in a homogeneous state, as invoked by the mean field approximation model. 相似文献