Matrix Synthesis of Magnetic Nanowires

In this work nanowires of magnetic metals (Co,Ni and Fe) were obtained via matrix synthesis, using etched track polymer template. The new data on electrodeposition of Ni was obtained. Two effects- the growth rate decrease (while the growing metal nanowires are filling the pores) and current density in-crease were investigated and discussed. The results of X-rays analysis obtained using synchrotrone source demonstrated the dependence of structure and composition of nanowires on the deposition voltage. Mossbauer spectroscopy was used for in-vestigation of Fe samples. The obtained data are in good agreement with X-rays results. When you are citing the document, use the following link http://essuir.sumdu.edu.ua/handle/123456789/3526

Metallic Nanowires on the Base of Porous Matrixes: Obtaining by Galvanic Replication, Structure and Some Properties

In this work nanowires (Co, Ni and Fe) were obtained via template synthesis, using etched track polymer matrix. The peculiarity of electrodeposition of Co and Ni was investigated and discussed: When filling the pores of a small diameter (0.1 and 0.2 microns) the dependence of current on time passes through a minimum. It can be supposed that the difficulties, appearing while filling nanosized pores, are related to the peculiarities of diffusion in narrow channels. The electrolyte for Fe deposition into nanosized pores was selected, the necessity of agitation was demonstrated. The results of X-rays analysis demonstrate that obtained wires have polycrystalline structure, which slightly depends on the deposition voltage. Mossbauer spectroscopy was used for investigation of Fe samples. The obtained sextet corresponds to α-Fe with polycrystalline structure. Two types of Fe atoms were found. The presence of two types of oxides was also detected. When you are citing the document, use the following link http://essuir.sumdu.edu.ua/handle/123456789/3494

Nanoparticles prepared from porous silicon nanowires for bio-imaging and sonodynamic therapy

Evaluation of cytotoxicity, photoluminescence, bio-imaging, and sonosensitizing properties of silicon nanoparticles (SiNPs) prepared by ultrasound grinding of porous silicon nanowires (SiNWs) have been investigated. SiNWs were formed by metal (silver)-assisted wet chemical etching of heavily boron-doped (100)-oriented single crystalline silicon wafers. The prepared SiNWs and aqueous suspensions of SiNPs exhibit efficient room temperature photoluminescence (PL) in the spectral region of 600 to 1,000 nm that is explained by the radiative recombination of excitons confined in small silicon nanocrystals, from which SiNWs and SiNPs consist of. On the one hand, in vitro studies have demonstrated low cytotoxicity of SiNPs and possibilities of their bio-imaging applications. On the other hand, it has been found that SiNPs can act as efficient sensitizers of ultrasound-induced suppression of the viability of Hep-2 cancer cells

Is there any future of optical discs?

Considered in this paper are causes for cutting compact discs out of information technology market. It has been shown a search of new technological solutions for efficient use of CDs in archive data storage

Non-local model of hollow cathode and glow discharge - theory calculations and experiment comparison

General form of the non-local equation for an ionization source in glow discharge and hollow cathode 3D-simulation is formulated. It is a fundamental equation in a hollow cathode theory, which allows to make up a complete set of field equations for a self-consistent problem in a stationary glow discharge and a hollow cathode. It enables to describe adequately the region of negative glow and the hollow cathode effect. Here you can see first attempts to compare calculation results of electrical dependences (pressure - voltage) and experimental data, - under conditions of gradual appearance of the hollow cathode effect.Comment: 4 pages, 2 figure

EDEPR of impurity centers embedded in silicon microcavities

We present the first findings of the new electrically-detected EPR (EDEPR) technique which reveal different shallow and deep centers without using the external cavity as well as the hf source and recorder, with measuring the only magnetoresistance of the Si-QW confined by the superconductor delta-barriers.Comment: 7 pages, 7 figure

Weakly--exceptional quotient singularities

A singularity is said to be weakly--exceptional if it has a unique purely log terminal blow up. In dimension $2$, V. Shokurov proved that weakly--exceptional quotient singularities are exactly those of types $D_{n}$, $E_{6}$, $E_{7}$, $E_{8}$. This paper classifies the weakly--exceptional quotient singularities in dimensions $3$ and $4$

Search for narrow resonances in e+ e- annihilation between 1.85 and 3.1 GeV with the KEDR Detector

We report results of a search for narrow resonances in e+ e- annihilation at center-of-mass energies between 1.85 and 3.1 GeV performed with the KEDR detector at the VEPP-4M e+ e- collider. The upper limit on the leptonic width of a narrow resonance Gamma(R -> ee) Br(R -> hadr) < 120 eV has been obtained (at 90 % C.L.)

Measurement of RudsR_{\text{uds}} and RR between 3.12 and 3.72 GeV at the KEDR detector

Using the KEDR detector at the VEPP-4M $e^+e^-$ collider, we have measured the values of $R_{\text{uds}}$ and $R$ at seven points of the center-of-mass energy between 3.12 and 3.72 GeV. The total achieved accuracy is about or better than $3.3\%$ at most of energy points with a systematic uncertainty of about $2.1\%$. At the moment it is the most accurate measurement of $R(s)$ in this energy range