Electronic Structure of a Chain-like Compound: TlSe

An ab-initio pseudopotential calculation using density functional theory within the local density approximation has been performed to investigate the electronic properties of TlSe which is of chain-like crystal geometry. The energy bands and effective masses along high symmetry directions, the density of states and valence charge density distributions cut through various planes are presented. The results have been discussed in terms of previously existing experimental and theoretical data, and comparisons with similar compounds have been made.Comment: 7 page

On the theory of nonselfadjoint operators of Schrödinger type with a matrix potential

The author studies the theory of dilation, characteristic function, and spectral analysis of dissipative operators of Schrodinger type with a matrix potential in Ζ^2((0, oo); Ε) which are an extension of a minimal symmetric operator with defect indices (2« , 2n) (dim£ = η < oo)

Nano-Size Layered Manganese-Calcium Oxide as an Efficient and Biomimetic Catalyst for Water Oxidation Under Acidic Conditions: Comparable To Platinum

Inspired by Nature's catalyst, a nano-size layered manganese-calcium oxide showed a low overvoltage for water oxidation in acidic solutions, which is comparable to platinum.Institute for Advanced Studies in Basic Sciences and the National Elite FoundationUS Department of Energy, Office of Basic Energy Sciences, Division of Chemical, Geochemical and Biological Sciences DE-FG02-86ER13622, DE-FG0209ER16119Russian Foundation for Basic Research 11-04-01389a, 12-0492101a, 13-04-92711aMolecular and Cell Biology Programs of the Russian Academy of SciencesCenter for Electrochemistr

Magnetospheric particle acceleration and X-ray emission of pulsars

The available data on isolated X-ray pulsars, their wind nebulae, and the supernova remnants which are connected to some of these sources are analyzed. It is shown that electric fields of neutron stars tear off charged particles from the surface of neutron star and trigger the acceleration of particles. The charged particles are accelerated mainly in the field of magneto-dipole radiation wave. Power and energy spectra of the charged particles depend on the strength of the magneto-dipole radiation. Therefore, the X-ray radiation is strongly dependent on the rate of rotational energy loss and weakly dependent on the electric field intensity. Coulomb interaction between the charged particles is the main factor for the energy loss and the X-ray spectra of the charged particles.Comment: minor correction on table format, 20 pages (4 figures, 1 table), submitted to International Journal of Modern Physics

Effects of the background radiation on radio pulsar and supernova remnant searches and the birth rates of these objects

In different directions of the Galaxy the Galactic background radio radiation and radiation of complex star formation regions which include large number of OB associations have different influences on radio pulsar (PSR) and supernova remnant (SNR) searches. In this work we analyse the effects of these background radiations on the observations of PSRs at 1400 MHz and SNRs at 1000 MHz. In the interval l=0$^o$$\pm60^o$ the PSRs with flux F$_{1400}$$>$0.2 mJy and the SNRs with surface brightness $\Sigma$$>10^{-21}$ Wm$^{-2}$Hz$^{-1}$sr$^{-1}$ are observable for all values of l and b. All the SNRs with $\Sigma$$>3\times10^{-22}$ Wm$^{-2}$Hz$^{-1}$sr$^{-1}$ can be observed in the interval 60$^o$$<$l$<300^o$. We have examined samples of PSRs and SNRs to estimate the birth rates of these objects in the region up to 3.2 kpc from the Sun and also in the Galaxy. The birth rate of PSRs is about one in 200 years and the birth rate of SNRs is about one in 65 years in our galaxy.Comment: revised versio

Linear Estimation of Particle Bulk Parameters from Multi-Wavelength Lidar Measurements

An algorithm for linear estimation of aerosol bulk properties such as particle volume, effective radius and complex refractive index from multiwavelength lidar measurements is presented. The approach uses the fact that the total aerosol concentration can well be approximated as a linear combination of aerosol characteristics measured by multiwavelength lidar. Therefore, the aerosol concentration can be estimated from lidar measurements without the need to derive the size distribution, which entails more sophisticated procedures. The definition of the coefficients required for the linear estimates is based on an expansion of the particle size distribution in terms of the measurement kernels. Once the coefficients are established, the approach permits fast retrieval of aerosol bulk properties when compared with the full regularization technique. In addition, the straightforward estimation of bulk properties stabilizes the inversion making it more resistant to noise in the optical data. Numerical tests demonstrate that for data sets containing three aerosol backscattering and two extinction coefficients (so called 3 + 2 ) the uncertainties in the retrieval of particle volume and surface area are below 45% when input data random uncertainties are below 20 %. Moreover, using linear estimates allows reliable retrievals even when the number of input data is reduced. To evaluate the approach, the results obtained using this technique are compared with those based on the previously developed full inversion scheme that relies on the regularization procedure. Both techniques were applied to the data measured by multiwavelength lidar at NASA/GSFC. The results obtained with both methods using the same observations are in good agreement. At the same time, the high speed of the retrieval using linear estimates makes the method preferable for generating aerosol information from extended lidar observations. To demonstrate the efficiency of the method, an extended time series of observations acquired in Turkey in May 2010 was processed using the linear estimates technique permitting, for what we believe to be the first time, temporal-height distributions of particle parameters

The thylakoid carbonic anhydrase associated with photosystem II is the component of inorganic carbon accumulating system in cells of halo- and alkaliphilic cyanobacterium Rhabdoderma lineare

AbstractThe organization of carbonic anhydrase (CA) system in halo- and alkaliphilic cyanobacterium Rhabdoderma lineare was studied by Western blot analysis and immunocytochemical electron microscopy. The presence of putative extracellular α-CA of 60 kDa in the glycocalyx, forming a tight sheath around the cell, and of two intracellular β-CA is reported. We show for the first time that the β-CA of 60 kDa is expressed constitutively and associated with polypeptides of photosystem II (β-CA-PS II). Another soluble β-CA of 25 kDa was induced in low-bicarbonate medium. Induction of synthesis of the latter β-CA was accompanied by an increase in the intracellular pool of inorganic carbon, which suggests an important role of this enzyme in the functioning of a CO2-concentrating mechanism

Components of Natural Photosynthetic Apparatus in Solar Cells

Oxygenic photosynthesis is a process of light energy conversion into the chemical energy using water and carbon dioxide. The efficiency of energy conversion in the primary processes of photosynthesis is close to 100%. Therefore, for many years, photosynthesis has attracted the attention of researchers as the most efficient and eco-friendly pathway of solar energy conversion for alternative energy systems. The recent advances in the design of optimal solar cells include the creation of converters, in which thylakoid membranes, photosystems and whole cells of cyanobacteria immobilized on nanostructured electrode are used. As the mechanism of solar energy conversion in photosynthesis is sustainable and environmentally safe, it has a great potential as an example of renewable energy device. Application of pigments such as Chl f and Chl d will extend the spectral diapason of light transforming systems allow to absorb the far-red and near infra-red photons of the spectrum (in the range 700-750 nm). This article presents the recent achievements and challenges in the area of solar cells based on photosynthetic systems