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The continuous effort for transitioning pulsed laser deposition (PLD) technique from an experimental tool into an industrial one can be sustained by the use of complex tools for in situ real-time monitoring of the deposition process. Langmuir Probe (LP) and optical emission spectroscopy (OES) measurements were used for plasma monitoring during PLD of silver films under various Ar pressure conditions. The LP measurements revealed a multi-structured distribution of the ions, which was strongly influenced by the increase of Ar pressure. The generation of highly energetic ions with the addition of Ar and the degree of Ar gas ionization was confirmed by OES measurements. A perturbative effect was seen under pressures higher than 10 Pa, where the presence of high electronic charges leads to an unstable behavior of plasma in the vicinity of the LP. The effect of these complex dynamics on the structure and quality of the deposited thin film was investigated revealing a strong correlation between the electronic distribution in plasma and thin film thickness profile.

Ultra-thin silver films of thicknesses of the order of 10 nm and less were prepared in different ambient conditions (vacuum, Ar, and N2) by pulsed laser deposition on glass and fused silica substrates. The in situ monitoring of electrical resistance of deposited films and optical emission spectroscopy of plasma were implemented as real-time analysis techniques. Change in the growth mechanism of the Ag layer in N2 ambient is expressed by an acceleration of the coalescence process, which shifts the percolation point toward lower mass thicknesses. The films prepared in vacuum and Ar ambient were found to be unstable for a final resistance in the range from 1 to 100 MΩ while the films deposited in N2 revealed stable electrical resistance. The percolation point was further lowered by introducing a sublayer of AgxOy for the film deposited in N2 gas. Based on data provided by AFM, SEM, and spectroscopic ellipsometry, different film formation mechanisms are discussed in relation to surface morphology and optical properties. Optical emission spectroscopy was used to monitor the deposition process and identify the species presented during the deposition process. The energy of the ejected particle is affected by the addition of ambient gas and depends on the properties of the working gas.

In this work, we deal with a study of the electron-transport behavior of zirconium nitride RF magnetron sputtered films using Zr target in reactive nitrogen ambient. The films were grown on silica-coated silicon substrates at a substrate temperature of 300°C. The growth process was monitored using an in-situ spectral ellipsometer in a spectral range from 245 to 1690 nm. The ellipsometric data were analyzed using a dispersion model based on Drude-Lorentz oscillators. We estimated electron-transport properties at each stage of the deposition process by analysis of the model parameters. The mechanism of the thickness-dependent electron-transport phenomenon of the ZrN films is discussed in this work.

In this work, a comparison of the microstructure of black and classic reflective aluminum films is provided. The N2 concentration during the magnetron sputtering deposition has a key impact on the growth process and final moth-eye-like morphology of black Al films. The study of films with thickness ~1.5 µm and ~8 µm and fully developed microstructure enabled us to clarify the origin of different optical properties of black and reflective Al. Atomic force microscopy measurements showed high roughnesses for both types of films leading to light scattering from their surface. In the case of black Al, the incident light is absorbed in a fractal-like nanoporous surface. Less than 3% of the intensity in the wavelength range from 190 nm to 1200 nm is reflected. Positronium formation in columnar nanopores with a diameter of 4 – 5 A was observed by positron annihilation lifetime spectroscopy. The nanoporosity rather than the roughness is the key feature of black films compared to reflective ones.

ZnO:Mo powders of nano- and microrods were fabricated by the hydrothermal growth method. ZnO:Mo thin films deposited on a fused silica glass substrate were synthesized for comparison as well. X-ray diffraction and fluorescence (XRD, XRF), scanning electron microscopy (SEM), electron paramagnetic resonance (EPR), photo- and radioluminescence (PL, RL) were applied to characterize these materials. The samples were also annealed in air at elevated temperatures to study the defects and luminescence modification. In particular, EPR spectra in the powder and thin film samples were composed of the signals originating from shallow donors before any treatment. The Mo5+ signal appeared after the annealing at 350 °C in the powder spectra. It existed prior to the treatment in the thin film samples. New EPR signal appears after X-ray irradiation in the powder samples. Red luminescence occurs in all powder samples. The intensity of this band demonstrated different dependences on the annealing temperatures in the samples with different Mo content. The exciton-related band at 380 nm never observed in the powder samples before the annealing, appears after the annealing at 350 °C. The strongest it was in the ZnO:Mo powder with low Mo content.

The article deals with problems of reconstruction of the facade and the associated problem of replacement or repair of the panels. In conventional buildings it is a smooth operation, but it is problematic in monument-protected objects. In the case of a common building, it is possible to choose any modern panels and simply replace them, but for historical objects we have to follow the claims and the rules of monument protection. In practice, it usually means the impossibility of use of modern panels, but at least a combination of old and modern technologies. Another possible solution to the problem is renovation, or repairs to the original state of the existing panels, of course with respect to the functionality of such panels. The implementation of such repairs must always be based on the technical and historical survey of the condition of the object and the repairs must be professionally designed. Subsequently, corrections are made, during which it is necessary to pay particular attention to observance of the technological procedures, rules and instructions particularly in terms of monument protection. However, the functionality of the works or elements made with regard to the quality of the environment within the building is not negligible. A common problem is the lack of control of technical requirements and functional requirements. Underestimation of the problems then leads to difficult repairs. The article points to the mistakes and problems of one such construction project on a historically protected chateau building.

This paper deals with the mass spectrometric characterization of atoms, radicals and ions generated in the RF magnetron discharges sputtering metal targets in Ne, Ar, Kr and Xe gases. In magnetron discharges different kinds of species such as atoms, radicals and positive and negative ions according to the target material and sputtering gas pressure can be generated. The mass spectrometry of the magnetron discharge, which gives the detailed information on these species, is of key importance for the development of new advanced thin films. The amount of individual atoms, radicals and ions and the ion energy distribution as a function of flow and pressure of the sputtering gas, and the magnetron power is discussed in detail. This article shows (1) the ion distribution functions of gas and sputtered target material ions as a function of sputtering gas pressure, (2) the evolution of the amount of single-ionized and double-ionized atoms of gases and metals generated in the RF discharge during sputtering of Ag films in various inert gases as a function of gas pressure, and (3) the contamination of the sputtered metallic films by the oxygen from a residual gas atmosphere in the deposition chamber at low film deposition rates.

In this work we present a quantum-classical molecular dynamics study of hydrogen irradiation of a single corrugated boron sheet in the incident energy range of 0.25–100 eV and report the resulting reflection, adsorption, and transmission probability. For this we use self-consistent charge tight binding density functional theory. A comparison of the irradiation results with our previous study on hydrogen detection using graphene shows a significant increase in the adsorption probability and a lower reflection rate for borophene. We benchmark our method of finding the interaction potentials of hydrogen and the boron sheet with plane wave density functional theory for validating our approach. We utilized the open boundary non-equilibrium Green’s function method to obtain conductivity of borophene as a function of hydrogen coverage. For voltages of up to 300 mV the systems have a linear volt–ampere characteristic and the resulting conductance decreases exponentially as a function of the hydrogen coverage. Our results suggest that borophene has favorable properties for its use as a hydrogen detector.

Currently, the adhesive joints are more and more regularly used as an alternative to mechanical joints. They often offer a more suitable, durable and faster possibility. They provide a solution with a more even distribution of stresses in the joint, which consequently allows an increase in the rigidity of the structure and allows it to withstand even heavy loads. High - strength flexible adhesive systems enable the implementation of effective structural joints, and although several decades have passed since the certification and installation of the first façade system with bonded anchoring, even today it is not a matter that is properly grounded in technical standards. A list of specific test procedures on whose basis the behaviour of the joint over the next 40 years could be predicted does not exist. On the basis of these facts, the authors have decided to subject the test samples both to laboratory measurements, where two methods were selected, as well as to expose them to the effects of real weather conditions for a 3-year period. Comparison of the real environment influence results and the methods of artificial aging showed that the selected conditioning methods adequately simulate the effects of weather conditions. V současné době se lepicí spoje stále častěji používají jako alternativa k mechanickým spojům. Často nabízejí vhodnější, trvanlivější a rychlejší možnost. Poskytují řešení s vysokým stupněm spolehlivosti ve spoji, což umožňuje zvýšit tuhost konstrukce. Vysoce pevné pružné lepicí systémy, ačkoliv uplynulo několik desetiletí od certifikace a instalace prvního fasádního systému s lepeným kotvením, ani dnes to není věc, která je řádně zakotvena v technických normách. Seznam konkrétních zkušebních postupů, na které lze předpovědět dalších 40 let, neexistuje. V případě tříletého období byli vybráni oba autoři i autoři tříletého období. Srovnání skutečných vlivů na životní prostředí a metod umělého stárnutí ukázalo, že vybrané metody kondicionování adekvátně simulují účinky povětrnostních podmínek.

The article deals with terrazzo surface that is done in the exterior and which shows defects and faults after execution. It was an entry portal of an unnamed institution where the placed surface began to show flaws more or less immediately after laying. The article simply provides a research of the problem, deals with the proposed procedure and presents the results of the technology supervision. Currently, after the second execution, the surface again shows defects and the way of their remedy will be addressed. The article also presents the basic aspects that need to be respected and not neglected when this type of surface is realized. Terrazzo is primarily an interior material (in our conditions), but it is also possible to make it in the exterior – it is a special kind of concrete mixture. The article tries to summarize the issue and provide basic information about the problem and its solutions. V současné době se lepicí spoje stále častěji používají jako alternativa k mechanickým spojům. Často nabízejí vhodnější, trvanlivější a rychlejší možnost. Poskytují řešení s vysokým stupněm spolehlivosti ve spoji, což umožňuje zvýšit tuhost konstrukce. Vysoce pevné pružné lepicí systémy, ačkoliv uplynulo několik desetiletí od certifikace a instalace prvního fasádního systému s lepeným kotvením, ani dnes to není věc, která je řádně zakotvena v technických normách. Seznam konkrétních zkušebních postupů, na které lze předpovědět dalších 40 let, neexistuje. V případě tříletého období byli vybráni oba autoři i autoři tříletého období. Srovnání skutečných vlivů na životní prostředí a metod umělého stárnutí ukázalo, že vybrané metody kondicionování adekvátně simulují účinky povětrnostních podmínek.

International audience; Eu doped ZnO thin films were deposited by pulsed laser deposition on fused silica substrate at room temperature and 300 °C in an oxygen ambient of pressure of 10 Pa. The films exhibited a wurtzite structure. The average transmittance exceeded 80% in the visible region confirming a good optical quality of the films. The characteristic emission of both Eu2+ and Eu3+ was observed when indirectly excited. The increase of substrate temperature to 300 °C led to higher crystallites size, lower efficiency of energy transfer from ZnO to Eu ions and lower resistivity of the film. XPS revealed the ratio of Eu divalent and trivalent states as 35%:65% and 27%:73% for sample deposited at room temperature and 300 °C, respectively. AFM showed higher RMS for the sample prepared at 300 °C.

Phthalocyanine and perylene are aromatic organic compounds. Metal complexes can be derived from phthalocyanine by substituting H2 in the central ring of the molecule by a metal ion. In the present work, positron annihilation spectroscopy was employed for characterization of the size distribution and local chemical environment of free volumes in perylene, phthalocyanine and its complexes with metals. The size distribution of free volumes was determined from the pick-off annihilation lifetimes of ortho-positronium. The local chemical environment of positron annihilation sites was characterized by the coincidence Doppler broadening spectroscopy.

In this work, we focus on study of the formation and behavior of molecules, radicals, and ions in ECR discharge in a mixture of argon and methane. Discharge properties are studied at various conditions; total gas flow (0–50 sccm), absorbed microwave power (0–900 W) and the partial pressure of methane (0–1.2 Pa). Neutral mass spectrometry does not reveal the presence of radical CH5 commonly described in literature. Spectra show the presence of atomic hydrogen H and especially H2 molecules. The number of CH4+ and CH3+ species shows that the amount of CH4+ in areas power up to 350 W is high, but with further increase of the power their amount decreases. With the increasing power the CH3+ ions are more intensively generated. The obtained data helps optimize process conditions for the fabrication of diamond and DLC thin films.

The contact thermal insulation system is a major trend in building construction in the Czech Republic. In this way both for new buildings and for renovations to improve thermal and technical parameters of buildings. Effort of an extension of the construction season, however, causes frequent visits of the application of this system in unsuitable weather conditions. One of the important layers in the systems ETICS (which is the contact thermal insulation of the building) is the basic layer with glass-fibre reinforcing mesh. Such a cover layer of thermal insulation and at the same time a basis for the final outer layer - plaster. Climatic conditions during application are given by the manufacturer. Normal temperature is indicated by + 5°C to +30°C. The lower boundary is not often observed. That's why I have my research and thesis focused on testing the parameters of the base layer made outside the ideal conditions. I thus produced samples underwent laboratory tests and watching the resulting parameters. This article provides a brief description of the testing methods and their advantages and disadvantages. The methods used were, for example, tests in flexural strength, pressure, water absorption test or tests of beginning and end of solidification. The most important findings of my research were the facts that significantly limit the applicability of standardized tests to determine the beginning and end of solidification. For the base layer samples of 4mm even these methods give very distorted information. Another effort of my research will be to verify these results and determine how it will be necessary to modify the methodology of testing, we received the relevant data. Preliminary hypothesis is at least the size of a substitute specimens - especially reducing the sample thickness from 40 mm to 4-6 mm, which corresponds to the reality of practical implementation. The data obtained would subsequently be used to adjust the rules for testing insulation systems. Data were obtained primarily from my research within VUT FAST brand FAST‑J‑10‑50

Thermostimulated luminescence properties (TSL) of sintered alumina were investigated. The main properties of ceramics of the type "Lucalox-CS", based on anion-defective alumina, have been investigated in detail. TSL, as a function of irradiated doses, shows maximum values with centered peaks at T = 63, 148, 291 and 347 °C. The respective absorption band of the manganese admixture was determined and the corresponding maximum TSL, the activation energies, and the frequency factors were calculated too. The TSL bleaching mechanism in alumina is associated with the temperature dependence of the probability of trapping in deep traps. This may be due to thermal ionization of excited states. The obtained results confirm the dependence on irradiated doses, temperature and structure of the material. This material could be used either as a substrate for the preparation of thin layers because of its strength, high thermal and chemical stability, high electrical resistance and transparency or as a dosimeter.

As dysphonia is assumed to be the most prevalent feature of hypokinetic dysarthria in Parkinson’s disease (PD), several acoustic approaches have been introduced for its assessment. However, the sensitivity of different acoustic measures to the occurrence of dysphonia in drug-naive de-novo patients with PD has not yet been explored. The goal of this study is to examine the performance of glottal source parametrization and compare it with traditional perturbation and cepstral measures. Sustained phonations of 40 de-novo drug-naive PD participants and 40 age- and sex-matched healthy controls were recorded. Each utterance was ranked by a set of glottal source parameters obtained by inverse adaptive filtering, the perturbation parameters, and cepstral peak prominence measures. Our results revealed the significant differences in the glottal source parameter Harmonic Richness Factor (HRF: p

Black and smooth Al films were characterized by the variable energy positron annihilation spectroscopy (VEPAS). It was found that in smooth films positronium (Ps) is formed on the surface only while in black metal films, it is formed also in nanoscopic pores inside the film. The mean pore size increases from the substrate to the surface due to increasing film roughness.

The article is focused on renovation, rehabilitation and reinforcement of high ferroconcrete walls. It tries to point out the experience of experts in solving problems with high ferroconcrete walls. During a revitalization of buildings of a military accommodation facility in Brno with basement and connecting corridors of an average height of 25 m, degradation of concrete, locally missing reinforcement and poor-quality concrete mixtures, the strength class of which varied between C8/10–C10/12, were found in these corridors. Along the height of the pilasters, the structure also showed the signs of torsion and it was assessed the structure also needs to be strengthened/reinforced besides the rehabilitation. The reinforcement structure had to be built from the very foundation of the building, it is linked to the existing wall and has three cascade levels. For the first two parts, a construction pit has been created with a Berliner wall, and these parts reach below the modified terrain, are reinforced with concrete reinforcement according to the structural project, concreted with cast concrete, and the foundation is reinforced with deep-based construction. The second and the third parts of the cascade stretch from the modified terrain between the pilasters to the top and they are made with a two-stage shotcrete technique, the first one has inbuilt concrete reinforcement with welded wire mesh and the second one composite mesh anchored by helical reinforcement without static effect. In terms of the damage of the structure, carbon fibre wrapping technique or grouting of the existing ferroconcrete structure was also used in the affected areas. The article also includes photo documentation of the repairs and structural damage prior to them.

The article presents pioneering research of textile chemiresistors on Evolon and Polyester substrates equipped with graphite electrodes and in-situ polymerized poly(tetrabutylphosphonium 3-sulfopropylacrylate) or poly(tributylhexylphosphonium 3-sulfopropylacrylate) sensitive layers. The DC- and AC- responses to 10 ppm of methanol, nitrogen dioxide, 4-bromoacetophenone, diethylmalonate and yperite were then investigated at laboratory temperature – the reference was “pure” synthetic air. Under these circumstances the DC- responses (SDC) varied from 0.48 to 1.36 and maximum AC- responses (Spa) from 8 to 26 deg. It was shown that sensor dynamics depends mainly on molecular weight of the analytes. Moreover, the magnitude of AC-responses correlated both qualitatively and quantitatively with the dipole moments of the analyzed molecules.

In the present work, defects created by implantation of hydrothermally grown ZnO single crystals of high quality with H+ions were investigated by positron annihilation lifetime (LT) spectroscopy combined with measurements of optical transmittance (OT) and photoluminescence (PL). First, zinc vacancies attached with one hydrogen impurity (VZn– 1H) atom were identified in the virgin ZnO single crystal. The ZnO single crystals were then bombarded by H+ions with the energy of 2.5 MeV to the fluence of 1016cm-2. It was found that VZn– VOdivacancies were introduced into ZnO by H+-implantation. Effects of H+-implantation on the optical activity of defects in ZnO lattice are characterised in the light of the present OT and PL data.

Although speech disorder is frequently an early and prominent clinical feature of Parkinson's disease (PD) as well as atypical parkinsonian syndromes (APS) such as progressive supranuclear palsy (PSP) and multiple system atrophy (MSA), there is a lack of objective and quantitative evidence to verify whether any specific speech characteristics allow differentiation between PD, PSP and MSA. Speech samples were acquired from 77 subjects including 15 PD, 12 PSP, 13 MSA and 37 healthy controls. The accurate differential diagnosis of dysarthria subtypes was based on the quantitative acoustic analysis of 16 speech dimensions. Dysarthria was uniformly present in all parkinsonian patients but was more severe in PSP and MSA than in PD. Whilst PD speakers manifested pure hypokinetic dysarthria, ataxic components were more affected in MSA whilst PSP subjects demonstrated severe deficits in hypokinetic and spastic elements of dysarthria. Dysarthria in PSP was dominated by increased dysfluency, decreased slow rate, inappropriate silences, deficits in vowel articulation and harsh voice quality whereas MSA by pitch fluctuations, excess intensity variations, prolonged phonemes, vocal tremor and strained-strangled voice quality. Objective speech measurements were able to discriminate between APS and PD with 95% accuracy and between PSP and MSA with 75% accuracy. Dysarthria severity in APS was related to overall disease severity (r = 0.54, p = 0.006). Dysarthria with various combinations of hypokinetic, spastic and ataxic components reflects differing pathophysiology in PD, PSP and MSA. Thus, motor speech examination may provide useful information in the evaluation of these diseases with similar manifestations.

Positronium formation in Au films was studied using a magnetically guided continuous slow positron beam with variable energy. Black Au film with porous morphology was compared with conventional smooth Au film. In the smooth Au film positronium is formed on the film surface only. The black Au film exhibits porous sub-surface region containing micro-cavities interconnected with surface. Positronium is formed on inner surfaces of micro-cavities in the sub-surface region and travels through interconnected cavities towards the surface. 3-gamma annihilation of ortho-positronium leaves a clear signature in two-dimensional coincidence Doppler broadening spectra. Measurements of 3-gamma annihilation contribution calculated from single gamma-ray and coincidence Doppler broadening spectra were calculated and compared.

The article reports on the contamination of Ag thin films sputtered from a pure Ag target in Ar and Ne gas by the RF magnetron by gas atoms contained in residual gas atmosphere in the deposition chamber at different values of the base pressure. The amount of O atoms generated at different values of base pressure is compared with the amount of Ag atoms sputtered at different deposition rates of Ag film. This comparison reveals a great problem in the formation of pure metallic films at low deposition rates and high values of the base pressure. No pure Ag films can be deposited at low in deposition chambers evacuated with diffusion or root pumps to the base pressures lower than 1 mPa only.

Although articulatory deficits represent an important manifestation of dysarthria in Parkinson's disease (PD), the most widely used methods currently available for the automatic evaluation of speech performance are focused on the assessment of dysphonia. The aim of the present study was to design a reliable automatic approach for the precise estimation of articulatory deficits in PD. Twenty-four individuals diagnosed with de novo PD and twenty-two age-matched healthy controls were recruited. Each participant performed diadochokinetic tasks based upon the fast repetition of /pa/-/ta/-/ka/ syllables. All phonemes were manually labeled and an algorithm for their automatic detection was designed. Subsequently, 13 features describing six different articulatory aspects of speech including vowel quality, coordination of laryngeal and supralaryngeal activity, precision of consonant articulation, tongue movement, occlusion weakening, and speech timing were analyzed. In addition, a classification experiment using a support vector machine based on articulatory features was proposed to differentiate between PD patients and healthy controls. The proposed detection algorithm reached approximately 80% accuracy for a 5 ms threshold of absolute difference between manually labeled references and automatically detected positions. When compared to controls, PD patients showed impaired articulatory performance in all investigated speech dimensions (p

A black aluminum (B-Al) film was deposited onto the surface of a stack structure of platinum/Pb(ZrxTi1 − x)O3/platinum (Pt/PZT/Pt) to convert light into a heat variation and the heat variation into a polarization change. A comparison was performed between B-Al/Pt/PZT/Pt and conventional Pt/PZT/Pt structures. An absorbance higher than 95% was measured for the B-Al layer over a large range of wavelengths varying from 350 nm to 1000 nm. The theoretical model shows that heat diffusion was extremely fast through the layers, and the sample holder played a key role in the variation and stabilization of the system temperature. A doubled variation of the polarization was observed when the light was applied onto the surface of the stack structure with stable B-Al on the top. This behavior was interpreted by the larger temperature variations induced under the highly absorptive B-Al layers, in good correlation with the theoretical model prediction based on the heat fluxes in the structures. This result is very promising for possible pyroelectric energy harvesting applications.

ZnO films with thickness of80 nm were grown by pulsed laser deposition (PLD) on MgO (1 0 0) single crys- tal and amorphous fused silica (FS) substrates. Structural studies of ZnO films and a high quality reference ZnO single crystal were performed by slow positron implantation spectroscopy (SPIS). It was found that ZnO films exhibit significantly higher density of defects than the reference ZnO crystal. Moreover, the ZnO film deposited on MgO substrate exhibits higher concentration of defects than the film deposited on amorphous FS substrate most probably due to a dense network of misfit dislocations. The ZnO films and the reference ZnO crystal were subsequently loaded with hydrogen by electrochemical cathodic charging. SPIS character- izations revealed that absorbed hydrogen introduces new defects into ZnO.

Using two complementary ultrasonic methods the complete set of elastic constants of the austenite phase of Ni Mn Ga ferromagnetic shape memory alloy was measured in magnetic field up to saturation and in temperature range 295–400 K. While the coefficients c 11 and c 44 were nearly independent of the field and the temperature, the shear coefficient c ′ increased strongly with increasing field and temperature. Experiment indicates that two independent mechanisms contribute to the anomalous shear softening of the c ′ coefficient in Ni Mn Ga austenite; the structural softening of the bcc lattice and the softening due to magneto-elastic coupling. Above the Curie point and in the saturation field only the structural softening took place with rate about 10 MPa/K. In the demagnetized state the combined softening was approximately 35 MPa/K. Similar dependencies on the temperature and the magnetic field were also observed for the ultrasound attenuation of the shear mode.

Racemic mixtures of six Troger's base derivatives were separated by chiral nonaqueous capillary electrophoresis. The separation protocol was optimized first for suitable solvents. Then the applicability of various salts dissolved in organic solvents and their mixtures was evaluated. As chiral selectors β-cyclodextrin and heptakis(2,6-di-O-methyl)-β-cyclodextrin at various concentrations were used. The best enantioselectivity for the studied analytes was obtained utilizing formamide as organic nonaqueous solvent containing a mixture of sodium citrate and tris(hydroxymethyl)aminomethane acetate as electrolytes, and β-cyclodextrin as chiral additive. The experimental results demonstrated the feasibility of nonaqueous capillary electrophoresis for enantioseparation of Troger's base derivatives. This technique represents a suitable alternative to more commonly used capillary electrophoresis in aqueous environment. Chirality 25:810–813, 2013. © 2013 Wiley Periodicals, Inc.

We focus our attention on the study of the initial stage of the silver growth. The silver layers were deposited by RF magnetron sputtering in pure argon or its mixture with nitrogen. The initial stage of the nucleation and the layer growth was studied by means of the optical and electrical monitoring, which are based on a principle of in-situ spectral ellipsometry. The measured data were fitted to a mathematical model. The nano-granular character of the grown layer is revealed by resonant features in the extinction coefficient spectra in visible spectral range. Thus, the mode of the layer growth (Volmer–Weber or Stranski–Krastanov) was clearly distinguished in the monitored data. The microstructure of the completed layer was further analyzed by X-ray diffraction (XRD) and atomic force microscopy (AFM). In this work, we show that the growth mode of the silver can be controlled by the deposition condition. We also present a method for preparation of an ultra-thin, continuous and smooth silver layer. The nucleation process is significantly influenced by presence of the nitrogen in the sputtering gas.

We have carried out a systematic study of the influence of Ne, Ar and Kr working gases on both plasma and film properties of RF magnetron sputtering of silver. The magnetron plasma was characterised by optical emission spectroscopy (OES) and mass spectrometry. Silver thin film morphology was examined by SEM and AFM. We studied influence of magnetron power and working gas pressure on the plasma composition. The magnetron power was varied from 25 to 100 W. The ambient pressure was changed from 0.5 Pa to 3 Pa. Both mass and OES spectra revealed presence of highly excited plasma in the substrate vicinity for all sputtering gases. The increasing OES signal intensities of Ag and Ag + with increasing RF power and gas pressure were observed. However, in Ar discharge there was no Ag + signal detected by OES at lower pressures of 0.5 Pa and 1 Pa. Similar profiles of the energy distributions of the ions with a maximum located around 19 eV were obtained in Ar and Kr discharges at pressure of 3 Pa while a maximum at 28 eV was measured in Ne discharge. Ag 2 + and AgX + radicals, where X is atom of particular inert-working gas, were observed in the mass spectra. Silver thin film deposited in Ne gas revealed lower roughness than the films deposited in the other gases.

The article reports mass spectrometric characterizations of ions generated in RF magnetron discharges generated using silver targets and Ne, Ar, Kr and Xe gases. Both the amount of ions and ion energies in magnetron discharges were investigated. The following ions X+, Ag+, (XAg)+, X2+, Ag2+, X++ and Ag++ were found in the RF discharges; here X = Ne, Ar, Kr, Xe is the inert gas atom and Ag is the silver atom. The amount of individual ions, their energies and ion energy distribution (IED) functions as a function of sputtering gas pressure were measured. It is shown that the sputtering gas pressure strongly influences the generation of ions, their amount and energy in the RF magnetron discharges. The knowledge of the energies and amounts of individual ions is of a key importance in the deposition of thin films with controlled properties using RF magnetron discharges.

It is currently unknown whether speech and limb motor effectors in Parkinson’s disease (PD) are controlled by similar underlying brain processes. Based on computerized objective analysis, the aim of this study was to evaluate potential correlation between speech and mechanical tests of upper limb motor function. Speech and upper limb motor tests were performed in 22 PD patients and 22 healthy controls. Quantitative acoustic analyses of eight key speech dimensions of hypokinetic dysarthria, including quality of voice, sequential motion rates, consonant articulation, vowel articulation, average loudness, loudness variability, pitch variability, and number of pauses, were performed. Upper limb movements were assessed using the motor part of the Unified Parkinson’s Disease Rating Scale, contactless three-dimensional motion capture system, blinded expert evaluation, and the Purdue Pegboard Test. Significant relationships were observed between the quality of voice assessed by jitter and amplitude decrement of finger tapping (r = 0.61, p = 0.003), consonant articulation evaluated using voice onset time and expert rating of finger tapping (r = 0.60, p = 0.003), and number of pauses and Purdue Pegboard Test score (r = 0.60, p = 0.004). The current study supports the hypothesis that speech impairment in PD shares, at least partially, similar pathophysiological processes with limb motor dysfunction. Vocal fold vibration irregularities appeared to be influenced by mechanisms similar to amplitude decrement during repetitive limb movements. Consonant articulation deficits were associated with decreased manual dexterity and movement speed, likely reflecting fine motor control involvement in PD.

Samarium-doped zinc oxide (ZnO:Sm)/zinc phthalocyanine (ZnPc) thin film multilayer structure was prepared by combination of pulsed laser deposition (PLD) and organic molecular evaporation (OME). ZnO:Sm thin film was grown by PLD (Nd:YAG, λ = 266 nm, τ = 6 ns) from Sm2O3:ZnO (1 % Sm) target in oxygen ambient at pressure of 10 and 20 Pa at room temperature on fused silica and Si(100) substrates. ZnPc thin film was deposited on ZnO:Sm layer by OME. ZnO:Sm films of c-axis-oriented hexagonal wurtzite structure and α-form ZnPc were obtained. Emission of intra-4f transition in Sm3+ ions and photoluminescence enhancement of near-band-edge emission of ZnO in ZnO:Sm/ZnPc were observed. Electrical properties were not affected by Sm3+ dopant as ZnO:Sm film exhibited high electrical resistivity ~5 × 104 Ω cm.

We report on excitation of the photoluminescence of lithium fluoride by means of the surface plasmon resonance of Al layer. Advantage of this method is high efficiency of the excitation, which is applicable to ultra-thin films. P-polarized UV diode laser light is coupled to the surface plasmon resonance using a fused silica prism in Kretschmann configuration. The angular dependence of the reflected intensity is measured using a theta–2theta goniometer. The surface plasmon at resonance condition induces photoluminescence in the adjacent lithium fluoride layer. The fluoride layers were deposited on Al-coated fused silica substrates by electron beam evaporation. For the experiment, we prepared several samples with thickness ranging from 20 to 71 nm. We studied the effect of the luminescence enhancement by the surface plasmon resonance effect. Strong quenching effect was observed in the thinnest LiF layer. Influence of X-ray irradiation on the photoluminescence was studied.

International audience; Zinc phthalocyanine (ZnPc) thin films were prepared by pulsed laser deposition (PLD) using KrF laser (λ = 248 nm, τ = 5 ns). The effect of laser fluence (in the region from 10 to 100 mJ/cm2) and repetition rate of 50 and 200 Hz to the film growth and its properties was investigated. The growth of ZnPc thin film was in situ monitored using transmission measurement in ultraviolet-visible spectral range. The optical properties in conjunction with density functional theory/time-dependent density functional theory calculations suggested the growth of the film in β-phase. X-ray diffraction also revealed crystalline character of the film. The electrical properties analyzed by van der Pauw method exhibited resistivity ρ ≈ 108–1010 Ω cm. Fourier transform infrared spectroscopy analyses revealed low deterioration of PLD deposited ZnPc films. We demonstrate that, by finely tuning the deposition conditions, PLD is a successful technique for fabrication of ZnPc thin films.

Textures, stresses, and strains, as well as the overall so-called real structure, are crucial for properties of thin films deposited by different methods and can have both positive and negative effects depending on the film and its application. They were studied by a combination of different X-ray diffraction (XRD) techniques for several ZnO films. The films prepared by pulsed laser deposition (PLD) on MgO and sapphire single-crystalline substrates and amorphous-fused silica showed different kinds of strong preferred orientation and also different stresses that could be estimated only from the analysis of quite narrow, nonzero intensity regions of diffraction spots. XRD line broadening was analyzed by a combination of different asymmetric scans. Fiber (0001) texture and tensile residual stresses were found on fused silica, while domains with local epitaxy and huge compressive stress were detected on MgO substrate, and surprisingly, very strong local epitaxy but not parallel to the (0001) sapphire substrate was observed. No residual stress was detected there. Some methodological aspects of the XRD studies of thin nanocrystalline films with strong preferred orientation are discussed.

The magnetron sputtering discharge used to deposit aluminum-doped zinc oxide was analyzed by energy-resolved ion mass spectrometry. The flux of negative ions was measured at three radial positions in the plane of the substrate holder. The oxygen flow φo 2 was varied from 0 to 17 sccm to investigate the discharge in all operation modes, i.e., metallic, transition, and oxide mode of sputtering. The existence of negative ions was determined from the energy spectra. Main attention was devoted to the investigation of O ― , O ― 2 , AlO ― , AlO ― 2 , ZnO ― , ZnO ― 2 , and AlO ― 3 negative ions and correlations of their intensities in the energy spectrum with discharge parameters (cathode voltage, magnetron power, and gas pressure). It was found that (i) intensities of negative ions exhibit maxima in the vicinity of transition between the metallic and transition mode of sputtering and (ii) in the oxide mode intensities of these ions are saturated.

Ab initio molecular dynamics simulations in NVT ensemble have been performed to investigate the finite temperature structure of the Mo(0 0 1) surface and its effect on work function (ϕ). In accord with previous experimental and theoretical work, our simulations predict that a termination with a stable reconstruction pattern is formed at T = 123 K. This pattern vanishes when temperature is increased to 423 K or 623 K and a disordered surface phase is formed whose time average corresponds to a bulk-like termination. Our results demonstrate that the surface relaxation is an important factor contributing to thermal variation of ϕ. At the lowest temperature, at which a stable reconstruction pattern is formed, the work function is found to increase by ∼0.23 eV compared to relaxed unreconstructed surface. The disappearance of stable reconstruction pattern at elevated temperatures leads to a decrease of ϕ by ∼0.07 eV. In contrast, the values computed for a non-reconstructing surface Mo(1 1 0) at T = 123 K, 423 K and 623 K are found to be nearly identical to the zero temperature value, which is a consequence of restricted atomic motion due to high packing density in this surface.

At present, the reactive magnetron sputtering is a well-mastered process currently used for industrial productionof various thin films and coatings. Great attention wasdevoted particularly to: (i) elimination of hysteresisphenomenon, (ii) removal of arcing at the surface ofsputtered target during reactive sputtering of electricallyinsulatingcompoundsand(iii)stabilizationofsputteringinthetransitionmode.

A series of transdermal permeation enhancers based on dicarboxylic acid esters was studied. Single-chain amphiphiles were markedly more effective than the double-chain ones. Monododecyl maleate, that is a cis derivative, was a more potent enhancer than its trans isomer, while the activity of succinates strongly depended on the donor vehicle. No difference between diastereoisomeric tartaric and meso-tartaric acid derivatives was found.

Series of N,N-dimethylamino acid esters was synthesized to study their transdermal permeation-enhancing potency, biodegradability and reversibility of action. Effects of chirality, linking chain length and polyfluorination were investigated. In vitro activities were evaluated using porcine skin and four model drugs—theophylline, hydrocortisone, adefovir and indomethacin. Biodegradability was determined using porcine esterase, reversibility was measured using electrical resistance. No differences in activity were found between (R), (S) and racemic dodecyl 2-(dimethylamino)propanoate (DDAIP). Substitution of hydrocarbon tail by fluorocarbon one resulted in loss of activity. Replacement of branched linking chain between nitrogen and ester of DDAIP by linear one markedly improved penetration-enhancing activity with optimum in 4–6C acid derivatives. Dodecyl 6-(dimethylamino)hexanoate (DDAK) was more potent than clinically used skin absorption enhancer DDAIP for theophylline (enhancement ratio of DDAK and DDAIP was 17.3 and 5.9, respectively), hydrocortisone (43.2 and 11.5) and adefovir (13.6 and 2.8), while DDAIP was better enhancer for indomethacin (8.7 and 22.8). DDAK was rapidly metabolized by porcine esterase, and displayed low acute toxicity. Electrical resistance of DDAK-treated skin barrier promptly recovered to control values. DDAK, highly effective, broad-spectrum, biodegradable and reversible transdermal permeation enhancer, is promising candidate for future research.