Search results for "Expansion"
showing 10 items of 630 documents
Pre-expanded Anterolateral Thigh Perforator Flap for Phalloplasty.
2016
The anterolateral thigh (ALT) perforator flap for phalloplasty is gaining popularity because it avoids the well-known scars of the radial forearm flap. However, scars are not eliminated, just moved to a different location, the thigh, that can for some patients be of great sexual value. Preexpansion of the ALT flap allows primary donor site closure, thus avoiding not only the unsightly appearance of a skin grafted ALT donor site, but also the skin graft donor site scar. Preoperative perforator location by means of computed tomography angiography allows safe expander placement through 2 small remote incisions.
On structural phase transitions in piperidinium halogenoantimonates(III) and bismuthates(III): X-ray, calorimetric, dilatometric, dielectric and Rama…
2000
Abstract Three piperidinium analogues: (C5H10NH2)2BiCl5, (C5H10NH2)2BiBr5 and (C5H10NH2)2SbBr5 have been studied by means of differential scanning calorimetry, thermal expansion, dielectric and Raman scattering techniques. Each piperidinium salt undergoes one high-temperature structural phase transition, which has been classified as an “order–disorder” type. All transitions are connected with onset of reorientational motion of the organic cations. The X-ray studies on (C5H10NH2)2BiCl5 show that it crystallises in orthorhombic Pna21 space group. The structure has been refined to R=0.0336. It consists of one-dimensional (BiCl52−)n polyanionic chains and two non-equivalent piperidinium cations…
Decoupling lattice and magnetic instabilities in frustrated CuMnO$_2$
2021
The $A$MnO$_{2}$ delafossites ($A$=Na, Cu), are model frustrated antiferromagnets, with triangular layers of Mn$^{3+}$~spins. At low temperatures ($T_{N}$=65 K), a $C2/m \rightarrow P\overline{1}$ transition is found in CuMnO$_2$, which breaks frustration and establishes magnetic order. In contrast to this clean transition, $A$=Na only shows short-range distortions at $T_N$. Here we report a systematic crystallographic, spectroscopic, and theoretical investigation of CuMnO$_2$. We show that, even in stoichiometric samples, non-zero anisotropic Cu displacements co-exist with magnetic order. Using X-ray/neutron diffraction and Raman scattering, we show that high pressures acts to decouple the…
ChemInform Abstract: Chemistry and Properties of Solids with the (NZP) Skeleton
2010
Abstract Solids with an [NZP] skeleton in their structure from a very broad family presenting very different properties with varying chemical composition. These properties range from radioactive nuclide immobilization and insulation to ionic and/or electronic conduction, extending to the field of very low thermal expansion among others. The open [NZP] skeleton provides the stability and flexibility necessary to form continuous ranges of solid solution, allowing the tailoring of the best composition-property-structure material. Chemical activity may become particularly high at the surface and absorption reactions and catalytic properties have the highest interest at present. In this paper, c…
Chemistry and properties of solids with the [NZP] skeleton
1993
Abstract Solids with an [NZP] skeleton in their structure from a very broad family presenting very different properties with varying chemical composition. These properties range from radioactive nuclide immobilization and insulation to ionic and/or electronic conduction, extending to the field of very low thermal expansion among others. The open [NZP] skeleton provides the stability and flexibility necessary to form continuous ranges of solid solution, allowing the tailoring of the best composition-property-structure material. Chemical activity may become particularly high at the surface and absorption reactions and catalytic properties have the highest interest at present. In this paper, c…
PHASE TRANSITIONS IN THE PLZT x/85/15 SOLID SOLUTIONS
2008
ABSTRACT Role of a La on the nature of phase transition in the PLZT x/85/15 is compared with the PLZT compositions of lower Zr/Ti ratio. Thermal dependence of the dielectric permittivity, thermal expansion and elastic modulus reveal sequential transfer from macroscopic ferroelectric to antiferroelectric and nonpolar state, if La concentration is increased. Diffused, from frequency independent thermal dependence of dielectric permittivity for compositions in certain La concentration range above 4 at% coexist with the well expressed phase transition between paraelectric and antiferroelectric phases.
Structural, magnetic, dielectric and mechanical properties of (Ba,Sr)MnO3 ceramics
2017
The authors acknowledge the CPU time allocation at Academic Computer Centre CYFRONET AGH in Cracow. This work was supported in part by PL-Grid Infrastructure and the European Regional Development Fund under the Infrastructure and Environment Programme [grant number UDA-POIS.13.01-023/09-00]. The research was partially carried out with the equipment purchased thanks to the financial support of the European Regional Development Fund in the framework of the Polish Innovation Economy Operational Program (contract no. POIG.02.01.00-12-023/08). L. Vasylechko acknowledges partial support of the Ukrainian Ministry of Education and Sciences under the Projects ?RZE?, ?KMON?, and ICDD Grant-in-Aid pro…
Features of Thermal Properties of Ferroelectric PLZT Ceramics in the Region of Phase Transition
2011
A study of specific heat and thermal expansion of PLZT-9/65/35 ceramics in the 150– 800 K range of temperatures is reported. Specific diffused features in behaviour of heat capacity and thermal expansion are revealed in the 250–650 K and 330–550 K range of temperature, respectively, and shown to be the result of the growth and changes of a system of ordering nano-size polarised regions. The features of heat capacity in the 250–650 K range of temperature are found to be related to two-level states (the Schottky anomaly). Obtained results are discussed together with data of structural and dielectric studies.
Crystallographic changes and thermal properties of lanthanum?strontium ferromanganites between RT and 700 �C
2005
Abstract X-ray powder diffraction was used to determine the crystallographic changes between room temperature (RT) and 700 °C of the (La 0.8 Sr 0.2 )(Mn 1− y Fe y )O 3± δ perovskites with y =0.2, 0.5, 0.8, 1 which can be considered as possible cathode materials for the ITSOFCs. For y =0.2, the rhombohedral symmetry was preserved in the whole temperature range. For y =1, a transition from orthorhombic to rhombohedral symmetry occurred at 290 °C. The compounds with y =0.5 and 0.8 were found to be diphasic at RT by combination of both rhombohedral and orthorhombic symmetries. They became only rhombohedral at 80 and 160 °C, respectively. This reversible transition is discussed in terms of iron …