Linear in-plane magnetoconductance and spin susceptibility of a 2D electron gas on a vicinal silicon surface

In this work we have studied the parallel magnetoresistance of a 2DEG near a vicinal silicon surface. An unusual, linear magnetoconductance is observed in the fields up to $B = 15$ T, which we explain by the effect of spin olarization on impurity scattering. This linear magnetoresistance shows strong anomalies near the boundaries of the minigap in the electron spectrum of the vicinal system.Comment: (accepted to Phys. Rev. B

Guiding the Way to Gamma-Ray Sources: X-ray Studies of Supernova Remnants

Supernova remnants have long been suggested as a class of potential counterparts to unidentified gamma-ray sources. The mechanisms by which such gamma-rays can arise may include emission from a pulsar associated with a remnant, or a variety of processes associated with energetic particles accelerated by the SNR shock. Imaging and spectral observations in the X-ray band can be used to identify properties of the remnants that lead to gamma-ray emission, including the presence of pulsar-driven nebulae, nonthermal X-ray emission from the SNR shells, and the interaction of SNRs with dense surrounding material.Comment: 16 pages, 11 figures, To appear in the proceedings of the workshop: "The Nature of the Unidentified Galactic Gamma-Ray Sources" held at INAOE, Mexico, October 2000, (A.Carraminana, O. Reiner and D. Thompson, eds.

Nonadditive changes in conductivity of micro PDLC under the influence of carbon nanotubes and magnetic nanoparticles

Investigated in this work has been the effect of impurities – magnetic nanoparticles (MN) and multiwall carbon nanotubes (MWNT) – separately and together on morphology and dielectric properties of nematic liquid crystal 6CHBT dispersed in polyvinyl alcohol (PDLC). It has been shown that the nanoparticles and nanotubes together change the morphology of PDLC practically in the same manner as every type of impurity singly. The impurities influence also additively on the permittivity at low frequencies and electron component of the conductivity in the polymer matrix. We have found that when MN and MWNT act jointly their ion component of the conductivity exceeds the total changes in conductivity by six times greater than when each type of impurity acts singly. The most probable reason for this nonadditive change in conductivity can be aggregation of these nanoparticles

Magnetotransport in a spatially modulated magnetic field

Duport Adrien Jean. Lecture de deux premiers articles du titre 1 de l'institution des officiers de police, lors de la séance du 28 décembre 1790. In: Archives Parlementaires de 1787 à 1860 - Première série (1787-1799) Tome XXI - Du 26 novembre 1790 au 2 janvier 1791. Paris : Librairie Administrative P. Dupont, 1885. p. 692

Effect of magnetic nanoparticles with various geometrical shapes on morphology and dielectric properties of nanodispersions of nematic liquid crystal in polymer matrix

Prepared in this work are dispersions of nematic liquid crystal in polyvinyl alcohol with sizes of liquid phase inclusions less than one micrometer (nano-polymer dispersed liquid crystal (PDLC)) by changing technology of mixing the components. It was shown that, like to the case of earlier examined dispersions with the droplet sizes 6 to 10 μm (micro-PDLC), the conductivity of nano-PDLC has two components: the ion one, which value does not depend on frequency, and the electron one, the value of which depends on frequency according to a power law. It was found that the ion conductivity of nano-PDLC is three orders of magnitude higher than that for micro-PDLC, and the exponent for the electron components of nano-PDLC conductivity is less than that for micro-PDLC. It was shown that the spherical and rod-like magnetic nanoparticles (MNs) influence in a different manner on the conductivity components of nano-PDLC. If for the maximum concentration of spherical MNs 2 * 10⁻³ wt.% the ion conductivity is 2-fold increased, then at the same concentration of rod-like MNs the ion conductivity value increases by more than one order of magnitud

Morphology and dielectric properties of polymer dispersed liquid crystal with magnetic nanoparticles

It has been shown that introduction of magnetic nanoparticles (MN) of various shapes with the concentration 10⁻¹ wt.% into polymer dispersed liquid crystal (PDLC) causes two effects: the size of liquid crystal droplets decreases, and the amount of the latter with through holes increases. MN increase the effective value of permittivity by more than one order within the frequency range 10⁻¹⁺ -10² HZ , as well as the electron and ion components of conductivity. MN reduce the exponent in the frequency dependence of the electron component of conductivity. The changes caused by the presence of the nanoparticles quantitatively depend on their shape

Riociguat treatment in patients with chronic thromboembolic pulmonary hypertension: Final safety data from the EXPERT registry

Objective: The soluble guanylate cyclase stimulator riociguat is approved for the treatment of adult patients with pulmonary arterial hypertension (PAH) and inoperable or persistent/recurrent chronic thromboembolic pulmonary hypertension (CTEPH) following Phase

Mechanism of Thermal Decomposition of Palladium β-Diketonates Vapour on Hot surface

The processes of thermal decomposition of palladium(II) β-diketonate complexes were investigated by a high-temperature mass spectrometric method with the use of a high-temperature molecular beam source. It was established that decomposition of the palladium complexes in gas phase processes proceeds by a radical mechanism and depends on temperature. For an additional proof of the existence of the radical particles the spin trap method was applied with a mass spectrometric identification of adducts. The following order of thermal stability of the complexes in gas phase was established : [MATH]. This order is reverse to the thermal stability in a solid state. The thermal decomposition of Pd(aa)2 and Pd(hfa)2 complexes in deuterium showed that the deuterium presence strongly accelerates the decomposition processes