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Color metallography of aluminum alloys can provide new structural knowledge or extend and refine structural knowledge compared to a black and white image. The basic principle of color metallography is to create a suitable film by etching. On samples coated with a suitable film, light interference is caused by the splitting of the incident light into components reflected at the air-layer interface and the layer-metal interface. The thickness of the film essentially determines at which colors the interference occurs. For films of suitable thickness, interference occurs in the blue, green and yellow regions. The film thickness depends on the chemical composition of the sample material, the chemical composition of the etchant and the etching time. If the etching conditions are kept constant (etchant type, etching time) and the chemical composition of the individual micro-areas changes significantly, it will be possible to distinguish the microareas by color contrast in the bright field. The results of color etching of aluminum alloys in different types of etchants will be presented. Using an automated apparatus, the same etching conditions will be maintained, including time and repeatability of movements in the etching, cleaning and drying process.

The present nuclear and cell body diameter measurements demonstrated size differences of the approximate cell space estimate occupied by the cell nucleus during the cell differentiation in lymphocytic, granulocytic and erythroid cell lineages. These lineages were used as convenient models because all differentiation steps were easily identified and accessible in diagnostic peripheral blood or bone marrow smears of blood donors (BDs), patients suffering from chronic lymphocytic leukemia (CLL), patients with chronic myeloid leukemia (CML) and refractory anemia (RA) of the myelodysplastic syndrome (MDS). The cell space occupied by the nucleus was constant and did not change during the cell differentiation in the lymphocytic cell lineages of BDs and CLL patients despite the decreased cell size. In contrary, the cell space occupied by the nucleus markedly decreased in differentiating cells of granulocytic and erythroid lineages of patients suffering from CML. In the erythroid cell lineage in patients with RA of MDS the small reduction of the cell space occupied by the nucleus during the differentiation was not significant. The measurements also indicated that in progenitor cells of all studied cell lineages nuclei occupied more than 70 % of the cell space. Thus, the nucleus-cytoplasmic morphological and functional equilibrium appeared to be characteristic for each differentiation step and each specific cell lineage.

This article introduces a new “linear heat balance (LHB) method” that is based on exact (physically correct) equation analytically derived from fundamental conduction–convection heat transfer equation. Therefore, the aim of this paper is to derive and analyze a new heat balance equation for sap flow calculation from measured temperature differences around continuously heated needle. The formula is derived from the steady-state conduction and convection heat transfer equation with linear source of heat power. This paper deals with the theoretical (analytical and numerical) and experimental analysis of heat and water transfer in the conductive xylem (sapwood) of trees. The analysis and verification of the new formula is based on numerical simulation (using finite element method) and the new LHB method is demonstrated on experimentally measured data. This new approach is important not only because of more exact sap flow calculation but also for information about thermal conductivity that can be used for water content estimation.

This paper deals with the numerical solution of a three-dimensional model of nonstationary nonlinear heat transfer in the sapwood of trees during sap flow measurement by a thermodynamic method based on volumetric heating of a stem segment (Trunk Heat Balance – THB – method). The model respects the dependence of physical properties on temperature and moisture and also the anisotropic nature of wood. The corresponding partial differential equation is then solved by finite element method. The main aim of this study was to analyze the thermal inertia of the THB method with horizontal references thermocouples. We compared the results of the simpler stationary and the more complex nonstationary model and we can conclude that the thermal inertia of the THB method is not negligible (mainly for smaller flows around 0.01 kg m −2 s −1 ). In addition, the authors have shown that the influence of moisture on the recorded sap flow data Q rec is negligible but there is small influence on Q fic and hence on the resulting sap flow measurement as was shown in their previous work. We also tested two new variants of temperature sensors arrangement and proved that the difference between them is very small and can be ignored.

Surface of intrinsic monocrystalline diamoncd is selectively terminated by hydrogen and oxygen atoms to create electrically conductive microscopic square with contact leads in corners. Polypyrrole (PPy) film is then electrochemically deposited onto the H-terminated square. The resulting PPy-diamond system is characterized under a broad-band light illumination by four probe resistivity and Hall mobility measurements and the in-plane transport properties of holes at the PPy-diamond interface are evaluated. We also discuss applicability of these techniques on this specific heterosystem.

Charge transfer in polypyrrole–diamond system is studied by conductivity measurements of a channel made of H-terminated diamond in the dark and under illumination. Micrometer-sized channels of conductive hydrogen-terminated diamond are lithographically fabricated on the surface of monocrystalline intrinsic diamond crystal by selective oxygen plasma treatment. The channels are interrupted by electrochemically synthesized micrometer-sized polypyrrole clusters. Similar characterizations are performed on channels interrupted by surface oxidation. Based on the increase and spectral response of the photo-current in the system, doping of diamond by charge carriers from polypyrrole is deduced.

Thin films of polypyrrole (PPy) are electrochemically polymerized in the thickness 25 nm on hydrogen-terminated intrinsic diamond surface exhibiting two-dimensional surface conductivity of 5 × 10 − 5 (S/). Opto-electronic properties of the system are characterized by Kelvin force microscopy detecting surface potentials. Shifts of the surface potentials of diamond and PPy under visible light illumination are attributed to sub- and super-band gap surface photovoltage effects changing energetic band bending in the range of 100–200 meV. We present a model considering influence of diamond surface termination, surface states and highly resistive bulk properties as well as excitonic transport in PPy. The model suggests a charge transfer between PPy and diamond.

SUMMARY Aims: Decreasing a number of hospital admissions is important for improving outcomes for people with schizophrenia. The Information Technology Aided Relapse Prevention Programme in Schizophrenia (ITAREPS) programme enables early pharmacological intervention in psychosis by identification of prodromal symptoms of relapse using home telemonitoring via a phone-to-PC SMS platform. Methods: This study was a 1-year extension of a previously published mirror-design followup evaluation of programme clinical effectiveness. In total, 73 patients with psychotic illness (45 patients from original sample and 28 newly added subjects) collaborating with 56 family members participated in the clinical evaluation. Results: There was a statistically significant 77% decrease in the number of hospitalisations during the mean 396.8 ± 249.4 days of participation in ITAREPS, compared with the same time period before participation in ITAREPS (Wilcoxonsigned ranks test, p < 0.00001), as well as significantly reduced number of hospitalisation days when in the ITAREPS (2365 hospitalisation days before and 991 days after ITAREPS enrolment respectively, Wilcoxon-signed ranks test, p < 0.003). Conclusion: The ITAREPS programme represents an effective tool in the long-term treatment of patients with psychotic disorders. What’s known Studies published so far suggest that crisis interventions such as increasing the dose of antipsychotic medication, based on early detection within a relapse prevention programme, reduce readmission rates in schizophrenia. Previous findings from ITAREPS mirror-image design followup showed a statistically significant 60% decrease in the number of hospitalisations during the mean 283.3 ± 111.9 days of participation in ITAREPS compared with the same time period before entering the programme (sign test, p < 0.004).

Mg 2 NiH 4 exists in two low-temperature modifications: monoclinic LT1 and monoclinic microtwinned LT2. Three samples of Mg 2 NiH 4 were prepared containing predominantly LT1 phase, predominantly LT2 phase and similar portions of both phases. Hydrogen desorption curves were measured and a parallel X-ray diffraction (XRD) study was performed. It was found that the great difference between amount of LT2 and LT1, measured by the ratio of the characteristic XRD peaks, leads to distinctly double-branched desorption curves. The LT2 phase substantially decelerates the desorption of hydrogen.

We investigate the first stages of nanocrystalline diamond (NCD) thin film growth at low substrate temperature. NCD films were grown on silicon substrates by microwave plasma enhanced chemical vapor deposition (CVD) for 0–300 min at a temperature of 410 °C. Si substrates were ultrasonically seeded in suspension of detonation nanocrystalline diamond powder. The seeding density approached values up to 1 ⁎ 1012 cm− 2, which allows growth of ultra-thin fully closed layers. Stagnation of the AFM roughness indicates that the low temperature NCD growth is a) delayed due to the surface contamination of the used nanodiamond powder and b) possibly dominated by the growth in the lateral direction. XPS measurements showed that the measured surface exhibits changes from a multi-phase composite (seeding layer) to single-phase one (NCD layer).

Effective diffusion coefficients D eff of radioisotope 65 Zn in Mg-based alloys AZ91 and QE22 with short Saffil fibers were measured by serial sectioning method in the temperature interval 648–728 K. The results were compared with 65 Zn volume diffusion coefficients D v obtained with the same materials without the reinforcement. This enabled to assess the influence of the interfaces between the matrix and the fibers upon the effective diffusion coefficients and to estimate the diffusion coefficients D i of Zn in Saffil/matrix interphase boundaries. It was observed that temperature dependence of both D eff and D i is significantly concave in the studied temperature interval, which was ascribed to relaxation of thermo-elastic stresses present in the composite as a consequence of considerable differences between the coefficients of thermal expansion (CTE) of both the constituents. D eff and D i tend to higher values close to 693 K, where the CTE is in a local minimum – i.e., where the maximum dislocation density by the phase interface can be expected.

Behaviour of a single dent within elastohydrodynamically lubricated contact has been observed both experimentally and numerically. The dent on the contact surface of the ball was artificially produced by a Rockwell indenter and the lip of raised metal around the perimeter of the depression was reduced by subsequent hand-polishing. Thin film colorimetric interferometry has provided precise film thickness data through the evaluation of chromatic interferograms. Obtained results are compared with data provided by a numerical solver for the contact problem that was developed and tested. From the results for different contact parameters it can be stated that good agreement between the numerical and experimental data was reached.

Mo tracer diffusion in Fe 76 Mo 8 Cu 1 B 15 alloy was studied using serial sectioning method in the temperature range 548–648 K. Sputtering by Ar + ions was applied as a sectioning technique. The measurement was carried out with the ribbon-like samples in as quenched state and in two states after pre-anneal 683 and 743 K/h. Measured concentration profiles consist of two distinct branches suggesting that two diffusion paths are operating. Diffusion coefficients D v calculated from the near-surface branch were attributed to Mo volume diffusion in amorphous phase, the higher ones, on the other hand are influenced by fast short-circuit diffusion.

Hydroaminations of methyl methacrylate with pyrrolidine and piperidine were found to proceed without a catalyst under mild conditions. Hydroamination with morpholine catalyzed by cationic palladium diphosphinoazine complexes was studied at temperatures 20–80 °C with catalyst loadings 0.1–1.05 mol%. Yields up to 91% were achieved and the promotion of the catalysis by triflic acid or its silver salt established. The influence of the phosphorus substitution in the diphosphinoazine on the catalytic activity was also observed.

Diffusion characteristics of 99Mo in three amorphous alloys were measured using a serial sectioning method combined with Ar+ ion beam sputtering technique. The study was carried out in the temperature interval 548–648 K. It was found that diffusion is controlled by two diffusion mechanisms and that the faster one is sensitive to thermal pre-treatment of the alloy. It was concluded that the slower diffusion mechanism is due to volume diffusion in the rest of the amorphous phase, the faster one can be ascribed to diffusion in interface between the crystallites and the rest of the amorphous phase.

Five diphosphinoazine palladium(II) amido complexes together with two phosphine-free and two triphenylphosphine-modified palladium(II) complexes were investigated as catalysts for the Heck reaction of styrene with 4-chlorobenzonitrile, bromobenzene and 4-bromobenzonitrile in dimethylacetamide with tributylamine as a base. The diphosphinoazine complexes competed well with the traditional catalysts; best conversions and turnover numbers were achieved with a vinyl-amide complex [(CH 3 OCOCH CCOOCH 3 )Pd{PPh 2 CH C(Bu t )NN C(Bu t )CH 2 PPh 2 }] giving TON of about 680 000 and TOF of 7710 h −1 in the reaction of 4-bromobenzonitrile. The TON of the chloroarene with the same complex was 729. Selectivities of the product formation were independent on the catalyst and little dependent on the substrate, the selectivity of the main product, ( Z )-1,2-diarylethylene, being always over 90%.

Water flow represents the biggest energy flow in vegetation which also causes its magnificent climatic effect. From all the water taken up by plants, the majority is transpired, leading to leaf cooling (associated with the heat of vaporization) and only minor amounts of water are consumed by all the other processes (such as photosynthesis transport of assimilates, growth, etc.). The transpiration can be estimated through the measurement of sap flow rates in a tree stem. A series of measurement methods were developed for this purpose and they are mostly based on thermodynamic principles. This paper deals with the numerical analysis of the sap flow measurement method based on the continuous needle heating of a stem segment, the measurement of temperature differences using the thermocouples around the heated domain and sap flow calculation from the temperature differences. An appropriate model of heat transfer in the sapwood of trees is derived and solved. The model is based on a partial differential equation describing conductionconvection heat transfer during continuous linear heating and it is solved by the finite element method.

Water relations of large pine and spruce trees were studied by the Mendel University Brno and Swedish Agricultural University Uppsala in central Sweden within the framework of NOPEX project. This particular study was focused on estimation of tree stem water storage and its importance for stand water balance. Proportions of solid matter, water and air in the bulk volume of wood along radii of tree stems were analysed using the gravimetric method. The cores of wood were taken with Suunto increment borer from pine and spruce trees of different social position in two neighbouring stands 50 and 100 year old. Data were interpreted in terms of the sapwood area and volume and water content in different tissues (sapwood and heartwood) and total amounts of water stored in tree stems. Total and available water in stem tissues was distinguished and the radial profile of water content was evaluated. The available water was discussed as an internal source for transpiration on the stand level.

Pure Fe-3.5 wt% C alloy was surface melted using a cw CO 2 laser and the microstructure of the laser tracks was investigated by scanning and transmission electron microscopy. Structure of the melted zones consisted of dendrites of partially transformed primary austenite and of very fine lamellar ledeburite. The secondary dendrite arm spacings were indicative of a cooling rate of ∼10 5 K s -1 , in good accord with calculations based on the model of a moving Gaussian beam. Using methods of quantitative metallography the volume fraction of dendrites within the melted zone and the volume fractions of the carbide and ferrite phases in the decomposed ledeburite were estimated. These data were combined with the results of a quantitative X-ray diffraction phase analysis (see Part II) and compared with the equilibrium phase diagram. It was found that the volume fraction of dendrites was near the equilibrium value while the volume content of cementite in the rapidly solidified structures was considerably higher than predicted from the equilibrium phase diagram.

The diffusivity of 14 C in austenitic alloys Fe-19at.%Ni-11at.%Cr- xC ( x = 0.010, 0.047, 0.065, 0.130, 0.288 and 0.809 at.%) has been studied in the temperature interval from 773 to 1023 K using a serial sectioning method. It appears that the carbon diffusion coefficients D increase with increasing average carbon concentration in accordance with an analogous dependence reported in the literature for the case of non-alloyed austenite FeC. The variation in the diffusion characteristics with the composition is explained in terms of C trapping by Cr atoms, and in terms of a repulsive interaction between nearest-neighbour C pairs. An empirical relation for calculation of D at various temperatures and carbon concentrations is proposed.

The collaboration TGV has finished measurement of 2νEC/EC decay of 106Cd with 10 g (Phase I) and 13.6 g (Phase II) samples (with enrichment of 75%), respectively. The times of measurements were 8687h (Phase I) and 12900h (Phase II). The half‐life limits (at 90% CL) were obtained for 2νEC/EC decay of 106Cd to the ground state of 106Pd as T1/2>3.0×1020 y (Phase I) and T1/2>4.2×1020 y (Phase II). The collaboration decided to continue with the study of 2νEC/EC decay of 106Cd using 23 g of an isotope enriched to 98.4%. We plan to use the TGV II spectrometer for this measurement and also Si pixel detectors for further study of double beta decay (ββ) processes.

Etude de la distribution du bismuth sur le sous-reseau dodecahedrique d'une couche mince de grenats fer yttrium bismuth. Mesure de la fluorescence des ions Bi 3+ , Y 3+ , Fe 3+ et Gd 3+ dans des conditions telles qu'une onde stationnaire se forme pendant la diffraction par la couche etudiee. On montre xperimentalement que les sites c z et c xy ne sont pas equivalents. la fraction d'ions Bi 3+ en positions c z est de 0.44±0.02 et de 0.56±0.02 en positions c xy .

The influence of carbon on iron grain boundary (GB) diffusion in polycrystalline austenitic alloys FeNiCr x C with x varying from 0.002 to 0.175 wt.% was studied. The measurements were carried out in the temperature range 853–1203 K using the sectioning method. It appeared that the increasing content of carbon caused a decrease in GB diffusivity, but the Arrhenius parameters Q b and P 0 increased to saturation for carbon concentration, C c ⩾ 0.062 wt.% C. From comparison with previous data concerning the dependence of GB characteristics on chromium content, it follows that the Arrhenius parameters depend primarily on the presence of a carbide phase in the GBs rather than on individual concentrations of carbon and chromium. The semi-empirical relation between the parameters Q b , P 0 and the total Cr and C concentration ( L = log [Cr] 23 [C] 6 ) has been proposed. This enables the estimation of Arrhenius parameters for Fe GB diffusion in FeNiCrC quaternary alloys: Q b [kJ mol −1 ] = 415 + 5.29 L for L ⩽ −37.5 or 217 for L > −37.5; log P 0 m 3 s −1 ] = −1.3+0.23 L for L ⩽ −37.5 or −10.0 for L > −37.5.

Pearlitic grey cast iron was surface melted using a 500 W CW CO2 laser at travel speeds 0.5–100 cm s−1. Detailed structural analysis of the laser modified layer was performed by optical and scanning electron microscopy (SEM), and microhardness depth profiles were measured. Temperature distribution was calculated from a three dimensional moving point source model, taking only the heat transfer into account. From the structural details observed in the austenitized zone some conclusions on the mechanism and kinetics of the pearlite austenite transformation at high heating rates were drawn. The melted zone consisted of primary austenite and ledeburite. At lower scanning speeds the structure was dendritic, at higher scanning speeds transition to dendritic-cellular structure was observed. From the secondary dendrite arm spacings the cooling rate during solidification was estimated as a function of the depth. Some discrepancies were found between our measurements and the literature data as well as predictions by the simple model neglecting convection in the melt.

The grain bpundary (GB) self-diffusion of chromium and iron in polycrystalline austenitic NiFeCr alloys has been studied from 858 to 1208 K using the sectioning method. It appears that the dependence of the GB diffusivity on the average nickel concentration is not so strong as the dependence on the chromium concentration. It is shown that, unlike the volume diffusion coefficients, the GB diffusivities of chromium were lower or equal to those of iron. With respect to their dependence on the chromium content of the alloy, the iron and chromium GB diffusivities reach a maximum and a minimum respectively at 10 wt.% Cr. The Arrhenius parameters for iron and chromium GB self-diffusion tend to increase with increasing chromium content, reaching constant values at about 20 wt.% Cr. The activation energy for chromium GB diffusion for all the chromium isoconcentration sections was always higher than that for iron GB diffusion.

Penetration profiles of 51Cr and 59Fe in polycrystalline austenitic alloys Ni–Fe–Cr after diffusion anneals at temperatures between 693 and 1208 K are studied. The temperatures and the diffusion times are chosen in order to keep the conditions of the so called B-type kinetics. The sectioning of diffusion zones of samples annealed above 858 K is carried out by grinding, at lower temperatures, by dc glow discharge sputtering. In general, it appears that the obtained penetration profiles, plotted in coordinates log c vs. x6/5, consist of two linear parts, each of which occurs due to a special type of grain boundary. The temperature dependence of the product P = αδDb (α, δ, and Db are the segregation factor, grain boundary width, and grain boundary diffusion coefficient, respectively) evaluated from both parts of the curves is the Arrhenius-type one. The dependence of activation enthalpy on Cr content is discussed qualitatively on the basis of an interaction between Cr and rest carbon. Es werden die Eindringprofile von 51Cr und 59Fe in polykristallinen austenitischen Ni–Fe–Cr-Legierungen nach Diffusionsgluhen zwischen 693 und 1208 K untersucht. Die Temperaturen und die Gluhzeiten werden so gewahlt, das die Diffusion im B-Stadium bleibt. Die Schichtenteilung der Diffusionszonen erfolgt oberhalb T = 855 K durch Schleifen und unterhalb dieser Temperatur durch Absputtern mittels Gleichspannungsglimmentladung. Es zeigt sich, das die Eindringprofile bei Auftragen von log c uber x6/5 aus zwei linearen Teilen bestehen, die der Diffusion entlang zweier verschiedener Korngrenzentypen entsprechen. Die Temperaturabhangigkeit von P (P = αδDb, wobei α, δ und Db der Segregationsfaktor, die Korngrenzenbreite bzw. der Korngrenzendiffusionskoeffizient sind.) entspricht fur beide Korngrenzentypen einer Arrheniusfunktion. Die Abhangigkeit der Aktivierungsenthalpie der Diffusion last sich auf Grund der Wechselwirkung zwischen Cr und Restkohlenstoff qualitativ interpretieren.

Penetration profiles after 64Cu and 59Fe indiffusion in the heterogeneous alloy Cu–52.3 wt% Fe are studied using the serial sectioning method. In the temperature range 1003 to 1203 K the interphase boundary (γ/ϵ for T > 1123 K and α/ϵ for T < 1123 K) diffusion coefficients of Cu and Fe are calculated using type A and/or type B kinetics models. Both, Cu and Fe diffusion characteristics show a discontinuity at the α/γ phase transition temperature of the Fe-rich phase. The Cu interphase diffusion characteristics obtained are close to the known data for the Cu grain boundary self-diffusion. Those obtained here for the Fe interphase diffusion at temperatures above 1123 K match well with the Fe grain boundary self-diffusion in the γ-phase below this temperature, on the other hand, they lie higher than all available literature data for the Fe grain boundary self-diffusion in the α-phase. This is believed to be a consequence of the lower b.c.c./f.c.c. interface coherency. Die Eindringprofile von 64Cu und 59Fe in Cu–52,3 Gew% Fe-Legierung werden im Temperaturbereich 1003 bis 1203 K mit Hilfe der Schichtenteilungsmethode untersucht. Die Interphasendiffusionskoeffizienten (IDK) von 64Cu und 59Fe fur die γ/ϵ (T > 1123 K)- und α/ϵ (T < 1123 K)-Interphasengrenzen werden aufgrund der kinetischen Modelle des Typs A und/oder B ermittelt. Die Cu- sowie die Fe-Diffusionseigenschaften zeigen eine Unstetigkeit bei der α/γ-Phasenubergangstemperatur der Fe-reichen Phase. Die vorgelegten IDK fur Cu stimmen mit denen fur die Cu-Korngrenzenselbstdiffusion uberein. Entsprechendes gilt fur den Fall der Fe Diffusion oberhalb T = 1123 K. Bei niedrigeren Temperaturen liegen jedoch die gemessenen IDK fur Fe hoher als die bekannten Parameter der Fe-Korngrenzenselbstdiffusion, was vermutlich eine Konsequenz der niedrigeren Koharenz von b.c.c./f.c.c. Interphasengrenzen ist.