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Journal of Thermal Analysis and Calorimetry
Authors: A. Rotaru, Catalin Constantinescu, P. Rotaru, Anca Moanţâ, M. Dumitru, Margareta Socaciu, Maria Dinescu, and E. Segal

Abstract  

A new synthesized 4CN type azomonoether, exhibiting dying properties, crystalline nature and generating interest as a material for non-linear optical applications was investigated. Modern devices incorporating liquid crystals tend to use thin films of such materials because of their special characteristics. Thermal stability studies are indispensable before attempting any deposition experiment. We have investigated the thermal behaviour of 4-[(4-chlorobenzyl)oxy]-4′-cyano-azobenzene (TG, DTG, DTA and DSC) in inert flow atmosphere, under non-isothermal conditions. The phase transitions were studied by repeated heating-cooling regimes, with intercalated isothermal steps. The thin films were deposited on silicon and quartz substrates by matrix assisted pulsed laser evaporation (MAPLE) using a Nd:YAG laser working at 266 nm. FTIR spectroscopy of the obtained thin films confirmed the preservation of the compound’s structure.

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Journal of Thermal Analysis and Calorimetry
Authors: A. Derafa, M.-C. Record, D. Mangelinck, R. Halimi, and A. Bouabellou

reactions between a metallic thin film and the silicon substrate. The investigation of the mechanism of phase formation is of great importance to understand the behavior of the materials and to optimize their properties. This study has already been performed

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titania thin films, such as electron-beam evaporation [ 12 ], ion-beam assisted deposition [ 13 ], DC reactive magnetron sputtering [ 14 ], RF reactive magnetron sputtering [ 15 ], sol–gel methods [ 16 ], chemical vapor deposition [ 17 ], and plasma

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behavior is typical for crystal growth controlled by crystal–liquid interface kinetics. The aim of this article is to study crystal growth kinetics of Sb 2 S 3 for selected compositions of thin films in (GeS 2 ) x (Sb 2 S 3 ) 1– x system. The

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Journal of Thermal Analysis and Calorimetry
Authors: E. Grell, A. Geoffroy, M. Stolz, E. Lewitzki, and M. von Raumer

Abstract  

Molecular functions and structural changes of membrane proteins in an aqueous environment can be elucidated by reaction-induced FTIR difference spectroscopy upon photolysis of caged compounds. The achieved detection of IR band changes even due to single amino acid residues is, however, only possible in the presence of very high protein concentrations, implying that a low water content must be present. In general, the films are formed by controlled dehydration of membrane protein suspensions at reduced pressure and low temperature. For the retention of enzymatic activity of Na,K-ATPase, for example, a cosolvent such as glycerol is required. In order to interprete the results obtained by FTIR spectroscopy, it is important to know whether essential properties of the proteins such as hydration are changed upon film formation. Therefore, a differential scanning calorimetry (DSC) study has been carried out with purified Na,K-ATPase and Ca-ATPase in suspension, in form of pellets obtained by high-speed ultracentrifugation and in thin films. As relevant thermoanalytical properties, the endothermic denaturation transitions of the proteins have been studied. For Na,K-ATPase in the presence of 20% glycerol as cosolvent, a single, comparatively narrow endothermic and irreversible denaturation transition with a denaturation enthalpy of about 1.7 MJ mol−1 and transition temperatures of about 65 and 70°C is found in concentrated suspension and in the state of the pellet, respectively. In the case of thin films suitable for IR spectroscopy, a characteristic change is observed in a reproducible manner. The enthalpy change of the remaining transition around 70°C is reduced but an additional transition at about 77°C is observed. Based on control experiments, the new high temperature transition is attributed to a partially dehydrated state of the protein. Furthermore, a comparatively broad endothermic transition around 20°C is found under conditions of high protein concentrations (film), which is tentatively assigned to a transition of the lipid environment of this integral membrane protein. Similar results are found for Ca-ATPase films. In the absence of glycerol, the deoxycholate treated enzyme in suspension exhibits a narrow endothermic main transition at 52°C with a denaturation enthalpy around 0.9 MJ mol−1. For the film of this protein, two almost equally large endothermic transitions are found at 59 and 77°C. Also here, the data are characteristic of partial protein dehydration. These results show clearly that DSC can easily be applied in a sensitive manner to control and characterize the integrity and hydration properties of concentrated protein samples in thin films.

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other Ti implants and their alloys [ 25 ]. To overcome the abovementioned problem, the TiC/a:C thin film would be used as a substitute of TiO 2 film. The reason to use TiC/a:C nanocomposite thin film is because it is more stable under a variety of harsh

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properties of thin films. Quartz crystal microbalance (QCM) is a more sensitive tool for mass loss and has also been used in measuring sublimation rates in thin films [ 4 , 5 ]. Some materials mass loss could be in the order of attograms. However, QCM

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Introduction Indium sulphide (In 2 S 3 ) thin films are often used as buffer layers instead of CdS in chalcopyrite absorber layer based solar cells [ 1 , 2 ]. Recently it was suggested that a transition metal substituted In 2

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IPFN in a technological perspective. Chapter 4 illustrates the proposed methodology using a case study of silicon-based thin film solar cell. Chapter 5 presents conclusions and future work. Related works Bibliometrics uses

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Abstract  

The use of proton resonance backscattering spectrometry for the estimation of carbon as thin films formed on a target material is discussed. Conventional He backscattering experiments were also carried out on TiVN films formed on beryllium backing but the determination of stoichiometry of these films were difficult using conventional software for depth resolution.

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