System for time-resolved laser absorption spectroscopy and its application to high-power impulse magnetron sputtering.

This paper deals with the development and construction of an apparatus for time-resolved tunable diode laser absorption spectroscopy (LAS) for the diagnostics of pulsed plasma. A detailed description of the extension of a progressive method of laser absorption spectroscopy in continuous regime to a direct triggering method of the time-resolved laser absorption spectroscopy (TR-LAS) is presented. The main advantage of the developed method is its capability to measure the time evolution of the whole absorption profile with a preset time resolution, which can be less than 1 µs. Therefore, the presented method of repetitive sampling applied on LAS in plasma processes is capable of simultaneous measurement of the density and kinetic temperature of selected particles. Its appropriate applications are to periodical processes in technological plasma, namely pulsed plasma discharges. The developed method of TR-LAS was applied to measurements of the temporal evolution of density and kinetic temperature of argon metastable species during high-power impulse magnetron sputtering of titanium and titanium dioxide thin films.

A modified Katsumata probe--Ion sensitive probe for measurement in non-magnetized plasmas.

A modified Katsumata probe has been developed for measurement of ion velocity distribution function (IVDF) in technological non-magnetized plasmas. A simple construction of the modified Katsumata probe consists of adding a pair of permanent Sm-Co magnets in front of Katsumata probe. A comparative study regarding IVDF measurement in a high power impulse magnetron sputtering system operating in pure argon atmosphere by means of developed modified Katsumata probe and commercially available gridded retarding field analyzer (RFA) has been carried out. A time-resolved measurement of IVDF for two different pressures whilst other plasma conditions have been kept unchanged has revealed that the main advantage of the modified Katsumata probe compared to the RFA consists in significantly smaller angular aperture of entrance orifice of modified Katsumata probe being approximately 15° in comparison with a commercial RFA having angular aperture more than 160°. It leads in much better velocity resolution in measured IVDF since the transversal part of velocity vector is much more suppressed compared to RFA. Furthermore, the modified Katsumata probe less suffers from collisions of ions in the space charge sheath in front or inside of the probe compared to the RFA.

Time-resolved tunable diode laser absorption spectroscopy of pulsed plasma.

A method for time-resolved tunable diode laser absorption spectroscopy (LAS) has been developed. In this Letter, we describe in detail a developed electronic module that controls the time resolution of the LAS system. The transistor-transistor logic signal triggering the plasma pulse is used for generation of two signals: the first one triggers fine tuning of the laser wavelength and the second one controls time-defined signal sampling from the absorption detector. The described method and electronic system enable investigation of the temporal evolution of the density and temperature of selected particles in technological plasma systems. The high-power impulse magnetron sputtering system with a period of 10 ms and a duty cycle of 1% has been used to verify this method. The temporal evolution of argon metastable density was measured in the active part of the pulse and in the afterglow. The resulting density of Ar* displays a double-peak structure with a first peak in the plasma "ON" phase and a second peak in the afterglow approximately 1 ms after the end of the pulse.

Notes on the photo-induced characteristics of transition metal-doped and undoped titanium dioxide thin films.

This study reports the preparation of thin nanoparticulate films of titanium dioxide and its modified version doped with a transition metal. The behavior of prepared films was described by means of their photocatalytic and photo-induced electrochemical properties. The TiO(2) and M/TiO(2) (M=Ag, Zr, Fe) thin films were produced via a standard sol-gel method using titanium n-butoxide, acetylacetone, and transition metal acetylacetonates as precursors. Prepared films were analyzed by a series of techniques involving XRD, Raman spectroscopy, SEM, AFM, and XPS. Their photocatalytic activity was monitored with the aid of decomposition of the model compound Rhodamine B in water. All films were then tested for their photo-induced electrochemical properties based on evaluation of polarization curves (photocurrents). The highest reaction rate constant (0.0101min(-1)), which was even higher than that for pure TiO(2), was obtained for the Ag/TiO(2) sample. The highest quantum yield of the charge collection was determined for the undoped TiO(2) film.

Atmospheric barrier-torch discharge deposited ZnO films: optical properties, doping and grain size effects.

Technology aspects, structure and characteristic properties of the atmospheric barrier torch discharge technique grown nominally pure and Al (0.1-5%) and Mn (0.05-0.5%) doped ZnO nanocrystalline thin films deposited on fused quartz substrates are reported. The set of films with various thicknesses in the range from 70 nm to 1000 nm were prepared for each composition. XRD and AFM analysis show well formed [001] preferably oriented hexagonal high quality films witch could be operatively fabricated in air atmosphere with controlled grain size. All films under study revealed n-type conductivity except some Mn doped films, which revealed p-type. Spectroscopic optical ellipsometry and luminescence spectroscopy studies evidenced luminescence properties typical for well formed ZnO and appreciable influence of Al doping and grain size on the optical absorption edge. Al doping shifts strongly absorption edge to the higher energies. The grain size decreasing (from 100 to 15 nm) leads to distinct diffusing of the absorption edge accompanied by increase of absorption in the near band edge region. For the smallest grains the pronounced Urbach-type absorption tail can be observed manifesting films inhomogeneity development.

[Concentration of acute phase proteins in serum of children with rheumatoid arthritis]. / Stezenie bialek ostrej fazy surowicy u dzieci z reumatoidalnym zapaleniem stawów.

An attempts was made at evaluation of the changes of acute phase proteins-seromucoid (BRS), alpha 1-acid glycoprotein (alpha 1-AGP), alpha 1-antitrypsin (alpha 1-AT), haptoglobin (Hp), C3 protein of complement system (C3), C1 esterase inhibitor (C1-INH), and transferrin (Tf) in the serum of children with rheumatoid arthritis. The patients were divided into clinical and age groups. The studies carried out have shown in ill children increase of BRS, alpha 1-AGP, alpha 1-AT, Hp, and C1-INH levels, During remission increased levels of alpha 1-AGP and Hp persisted. In the studied clinical groups a positive correlation was found between the intensity of changes of the studied indices and the degree of disease activity. In the age groups greater increase of the levels of the studied acute phase proteins was found in the group of preschool children and the group of puberty spurt. The obtained results suggest that the determination of acute phase proteins may be useful in laboratory investigation of children with rheumatoid arthritis.

Rat interferons. IV. Sialoproteins in rat serum.

Introduction of virus as inductor of interferon into rats caused a decline in serum levels of sialic acid in blood taken at the time of maximum interferon activity. Differences in the acute phase proteins were dependent on the type of virus used for induction. NDV injected intravenously did not lower serum levels of seromucoid, but given together with DMSO markedly depressed the content of this protein in the serum. Stimulation of interferon production by Sindbis virus was accompanied by a significant rise in levels of seromucoid. The same virus given together with DMSO had no effect on protein level, which remained normal, but lowered the content of sialic acid in proteins.