Palladium(II) complexes of benzaldehyde and 2-hydroxybenzaldehyde-4-H/phenyl-<Emphasis Type="Italic">S</Emphasis>-ethyl/allyl-thiosemicarbazones

The thiosemicarbazone derivatives R₁-C₆H₄-CH=N-N=(C-S-R₂)-NH-R₃ [R₁ = H, OH; R₂ = H, Ph; R₃ = C₂H₅, C₃H₅] were prepared by a modified general method. The Pd(II) complexes of the thiosemicarbazone ligands L^I–VI were isolated in the compositions [Pd(L)Cl₂], [Pd(L)Cl] and [Pd(L)₂]. The 1: 1 and 1: 2 metal complexes have non-ionic character, and the compounds were characterized by analytical data and infrared and proton resonance spectroscopy. The cis-trans and syn-anti isomers of the thiosemicarbazones were determined by means of ¹H NMR, and the coordination behavior of the polydentate thiosemicarbazone ligands towards the palladium ion were discussed.     

Thermal characterization of highT c superconductors through the photodeflection method

The photothermal deflection method has been used for thermal diffusivity measurements on bulk YBCO and BISCCO highT _c superconductors. A cryostat set up is used to perform photothermal measurements from room temperature down to 77 K.     

Transverse photothermal deflection spectroscopy (PDS) applied to thermal diffusiyity measurements

Transverse photothermal deflection spectroscopy(PDS) is applied for the determination of thermal diffusivities of solid surfaces. The theory of PDS is briefly recalled and some approximated analytical formulae concerning the transverse configuration are derived. In materials where the thermal diffusivity is smaller than that of the air, the dependence of the deflection angle on the displacement between pump and probe beams is shown to have a minimum that relates to the thermal diffusivity, thereby allowing its straightforward measurement. Measurements carried out on Al₂O₃ samples with different porosities at room temperature show a good agreement between experiment and theory.

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Zusammenfassung Die transverse photothermische Reflektionsspektroskopie (PDS) wird zur Bestimmung der thermischen Diffusivität von festen Oberflächen herangezogen. Die Theorie der PDS wird kurz dargelegt und einige sich auf die transverse Konfiguration beziehenden analytischen Näherungsgleichungen abgeleitet. Es wird gezeigt, daß bei Materialien mit kleinerer thermischer Diffusivität als Luft die Abhängigkeit des Deflektionswinkels von der Ablenkung zwischen Pumpen- und Probenstrahl ein Minimum aufweist, das mit der thermischen Diffusivität im Zusammenhang steht und somit deren zuverlässige Messung ermöglicht. An Al₂O₃-Proben unterschiedlicher Porosität bei Raumtemperatur ausgeführte Messungen zeigen gute Übereinstimmung von Experiment und Theorie.

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Superconducting properties of polycrystalline YBCO prepared by a pyrolytic process

Il Nuovo Cimento D - Polycrystalline YBCO was prepared by a pyrolytic process starting from citrate and tartrate precursors. The effect of the precursor on the superconducting properties was...     

DSC characterization of induced stresses during traditional ceramics forming process

The recovery of metals is the process of softening without crystallization in the mechanical stressed pieces and is well characterized by DSC measurements at temperatures < 600°C. The present investigation was undertaken to detect similar effects also in traditional ceramics. Several ceramic samples, coming from different productions, were thermally analyzed by DSC and the presence, in the most stressed samples, of an exothermic peak at about 350°C, was detected, confirming the presence of recovery in the ceramics too. However, owing to the complex structures of these materials, at present no mathematical model could be introduced. This revised version was published online in July 2006 with corrections to the Cover Date.     

Effect of microrheological processes on the adhesion of a combination of film materials

The temperature and time functions of combination of film materials, one of which is in the glass state and the other in the glass transition state, have shown that the kinetics of the formation of the actual contact surface depend on microrheological processes. Theoretical functions for stress disrupting the adhesion bond have been proposed, and have been checked experimentally by using electron microscope and rheological methods.Moscow Technological Institute of the Meat and Milk Industry. Translated from Mekhanika Polimerov, No. 2, pp. 203–208, March–April, 1970.     

Pyrolysis of black cumin seed: Significance of catalyst and temperature product yields and chromatographic characterization

In this study, black cumin seed cake was transformed into liquid and solid products via pyrolysis method at 300, 400 and 500?°C with Ca(OH)₂, Al₂O₃, SnCl₄.5H₂O catalysts and without catalyst. The obtained liquid and solid products were examined with GC-MS, Elemental, FT-IR, ¹H NMR and SEM analysis methods. The highest liquid product yield was obtained as 30% in the presence of Al₂O₃ catalyst. All catalysts were found to be effective on conversion. According to the results of the elemental analysis of the liquid products obtained at the end of the experiments, HHV values were found between 32.44 and 36.19?Mj/kg. According to the results of GC-MS analysis of the liquid products, in total, 77, 61 and 66 pieces of compounds consist of monoaromatics, aliphatics, oxygenated compounds with different properties were obtained at 300, 400 and 500?°C reaction temperatures respectively. The results of the FT-IR and ¹H NMR that are used to examine the liquid products support the results of GC-MS.     

An example concerning fixed points

An example is given of a contractionT defined on a bounded closed convex subset of Hilbert space for which ((I+T)/2) ⁿ does not converge.