Microanalysis of Pd and V-doped TiO2 thin films prepared by sputtering

Thin films of TiO₂ doped with vanadium and palladium, prepared by the magnetron sputtering method, were studied by means of X-ray diffraction (XRD), Scanning Electron Microscopy with Energy Disperse Spectrometer (SEM-EDS) and Atomic Force Microscopy (AFM). Investigations have brought important information about microstructure due to dopant incorporation in the TiO₂ host lattice. Directly after deposition thin films were XRD-amorphous and SEM investigations did not reveal details on the microstructure. Analysis of the topography of prepared thin films required application of Atomic Force Microscope. The AFM images show that as-deposited sample was dense with grain sizes varied in the range of 5.5 nm-10 nm, that indicated high quality nanocrystalline behavior. Additional annealing results in the formation of three phases in the thin film, e.g. (Ti,V)O₂ — solid solution, PdO and metallic inclusions of Pd. SEM-EDS system allowed analysis of the elemental composition, especially the V one, which lines have not been evidenced in the XRD diffraction pattern. EDS maps show homogenous distribution of elements Ti, O, V, Pd in prepared thin films.     

Efficient broadcasting in radio networks with long-range interference

We study broadcasting, also known as one-to-all communication, in synchronous radio networks with known topology modeled by undirected (symmetric) graphs, where the interference range of a node is likely exceeding its transmission range. In this model, if two nodes are connected by a transmission edge they can communicate directly. On the other hand, if two nodes are connected by an interference edge they cannot communicate directly and transmission of one node disables recipience of any message at the other node. For a network $G,$ we term the smallest integer $d$ , s.t., for any interference edge $e$ there exists a simple path formed of at most $d$ transmission edges connecting the endpoints of $e$ as its interference distance $d_I$ . In this model the schedule of transmissions is precomputed in advance. It is based on the full knowledge of the size and the topology (including location of transmission and interference edges) of the network. We are interested in the design of fast broadcasting schedules that are energy efficient, i.e., based on a bounded number of transmissions executed at each node. We adopt $n$ as the number of nodes, $D_T$ is the diameter of the subnetwork induced by the transmission edges, and $\varDelta $ refers to the maximum combined degree (formed of transmission and interference edges) of the network. We contribute the following new results: (1) We prove that for networks with the interference distance $d_I\ge 2$ any broadcasting schedule requires at least $D_T+\varOmega (\varDelta \cdot \frac{\log {n}}{\log {\varDelta }})$ rounds. (2) We provide for networks modeled by bipartite graphs an algorithm that computes $1$ -shot (each node transmits at most once) broadcasting schedules of length $O(\varDelta \cdot \log {n})$ . (3) The main result of the paper is an algorithm that computes a $1$ -shot broadcasting schedule of length at most $4 \cdot D_T + O(\varDelta \cdot d_I \cdot \log ^4{n})$ for networks with arbitrary topology. Note that in view of the lower bound from (1) if $d_I$ is poly-logarithmic in $n$ this broadcast schedule is a poly-logarithmic factor away from the optimal solution.     

Integration of transparent glass window with LTCC technology for μTAS application

The LTCC substrate makes it possible to build various microsystems which integrate not only passive components such as resistors, capacitors and inductors but also 3D structures such as cavities and channels. Nevertheless non-transparency is a main limitation of the LTCC-based microfluidic systems. The goal of this paper is to present technology which allows an optical transparent element to integrate with LTCC co-firing process. A micrototal analysis system (μTAS), which is based on the LTCC–glass technology, enables optical measurements. The study shows that integration of sodium glass material is feasible not only with zero-shrinkage LTCC (HL 2000, HL 800) but also with a standard one (DP 951). A FEA (finite element analysis) is used to calculate stress inside the LTCC–glass structure. A series of LTCC–glass windows with different sizes and shapes is investigated to observe size limitation of the integration method. The example ceramic–glass structures (chambers, mixer) with glass windows are made in order to present the possibilities of this new technology.     

Properties of laser cut LTCC heaters

This article describes fabrication and properties of buried microheaters made inside low temperature co-fired ceramics (LTCC) structures. Laser cutting is used for meander pattern generation in dried Pt, PtAu or PdAg conductive pads. The electrical characterisation of microheaters is based on measurement and analysis of R(T) dependence in the range from 20°C to 850°C, measurement and analysis of thermal dynamic properties, long-term high-temperature passive or active ageing and behaviour of the heater in a pulse operation mode. The presented results are very promising for application of LTCC microheaters in various microsystem devices.     

The afferent neural response to electrotactile stimuli: preliminary results.

We recorded action potentials from three RA fibers innervating primate fingerpad, while applying electrotactile (electrocutaneous) stimulation. Negative pulses required 1.3-1.5 times more current than positive ones for entrainment. The strength-duration time constant was approximately 151 micros. Suprathreshold sinusoidal vibration synchronized to 30-Hz electrotactile pulses changed the electrotactile entrainment current slightly, indicating a possible electrical-mechanical transduction interaction.     

Sintering of Colloidal Ru/γ-Al2O3 Catalyst in Hydrogen

Colloidal 5.1 wt% Ru/γ-Al₂O₃ catalyst was prepared by a microwave assisted, solvothermal reduction of RuCl₃ in ethylene glycol in the presence of γ-Al₂O₃. The catalyst subjected to heat-treatment in hydrogen up to 700 °C, was characterized by BET, XRD, TEM and H₂ chemisorption. As-prepared catalyst contained Ru nanoparticles with mean size of 1.5 nm and narrow size distribution uniformly distributed over the support. The nanoparticles were stable on the alumina to 500 °C, but treatment at 600–700 °C caused some sintering of Ru due to migration and coalescence of a part of smallest ruthenium nanoparticles. However, even after H₂ treatment at 700 °C, large amount of Ru nanoparticles with sizes of 1–3 nm remained in the catalyst. H₂ chemisorption data revealed decrease of Ru dispersion from 0.28 to 0.19 by hydrogen treatment at 700 °C and were in good correspondence with TEM results. On the contrary, mean crystallite sizes obtained from XRD were strongly overestimated.     

Three-dimensional modeling of the I-TevI homing endonuclease catalytic domain, a GIY-YIG superfamily member, using NMR restraints and Monte Carlo dynamics

Using a recent version of the SICHO algorithm for in silicoprotein folding, we made a blind prediction of the tertiarystructure of the N-terminal, independently folded, catalyticdomain (CD) of the I-TevI homing endonuclease, a representativeof the GIY–YIG superfamily of homing endonucleases. Thesecondary structure of the I-TevI CD has been determined usingNMR spectroscopy, but computational sequence analysis failedto detect any protein of known tertiary structure related tothe GIY–YIG nucleases (Kowalski et al., Nucleic AcidsRes., 1999, 27, 2115–2125). To provide further insightinto the structure–function relationships of all GIY–YIGsuperfamily members, including the recently described subfamilyof type II restriction enzymes (Bujnicki et al., Trends Biochem.Sci., 2000, 26, 9–11), we incorporated the experimentallydetermined and predicted secondary and tertiary restraints ina reduced (side chain only) protein model, which was minimizedby Monte Carlo dynamics and simulated annealing. The subsequentlyelaborated full atomic model of the I-TevI CD allows the availableexperimental data to be put into a structural context and suggeststhat the GIY–YIG domain may dimerize in order to bringtogether the conserved residues of the active site.     

Precontact 50-kHz vocalizations in male rats during acquisition of sexual experience.

50-kHz ultrasonic vocalizations emitted by male rats during a 5-min period before introduction of a female (precontact vocalizations [PVs]) were analyzed in the context of acquisition of sexual experience. Changes in the main copulatory parameters and their N-methyl-D-aspartate (NMDA) receptor dependence, the role of contact with either anestrous or estrous females, and conditioning to odor and background cues were also investigated. Mount latency (ML) and intromission latency (IL) decreased after the 1st copulatory session, but ejaculation latency (EL) changed significantly only starting from the 4th session onward. The number of PVs gradually increased during the first 3–4 sessions. Blocking of NMDA receptors affected PVs and EL but not ML or IL. After a 5-month break in copulatory sessions, ML remained unchanged, whereas EL increased and the number of PVs decreased significantly. PVs were most robustly elevated by contact with estrous females. Exposure to background cues resulted in a linear decrease in number of PVs during 10 subsequent sessions without exposure to a female. The results suggest that, in the course of acquisition of a sexual experience, PVs reflect a learning process that depends on a rewarding value of sociosexual contact. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Equivalent Circuits for an SLG Fault Distance Evaluation by Curve Fitting in Compensated Distribution Systems

We present an extended zero-sequence equivalent circuit for compensated medium-voltage systems, with load current contribution accounted for in the zero-sequence voltage drop accounts. It opens its application to complete and eventually filtered waveforms, rather than only one frequency component. Consequently, the new zero-sequence circuit adapts more to fault-location tasks both in overhead and in cable systems, particularly in the presence of important capacitive currents, where extraction of the main charging current may be not an obvious operation. We have applied it in curve-fitting procedures for the evaluation of a single-line-to-ground fault distance. Fault resistance, fault position, and inception angle are fitting parameters. Then, the fault position is given with several percent average error, within a 10% untuning range, at small and large inception angles, and for a fault resistance up to 3 kOmega to be compared to the 50-Omega limit achieved before.     

Low splice loss between 34 /spl mu/m core diameter Bragg fibre and G-652 fibre by using micro-optics

The splice loss at 1.55 /spl mu/m between a 34 /spl mu/m core diameter singlemode photonic bandgap fibre and a G-652 fibre has been dramatically reduced from 2.5 to 0.8 dB by using a micro-optics composed of graded-index and coreless pure silica fibres.