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Journal of Thermal Analysis and Calorimetry
Authors: Michele Iafisco, Ismaela Foltran, Michele Di Foggia, Sergio Bonora and Norberto Roveri

-dimensional structure, which can be influenced by chemical and physical factors (pH, temperature, pressure, etc.) [ 3 , 12 ]. Thermal analysis offers the best way to obtain precise and reproducible data on the overall denaturation process, while Raman

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J. Robertson 2004 Raman spectroscopy of amorphous, nanostructured, diamond-like carbon, and nanodiamond Philosophical Transactions Royal Society London A

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methods, both destructive and non-destructive, have been used for the qualitative and quantitative characterisation of ancient mortars, like SEM/EDX, FTIR, Raman micro-spectroscopy, DSC/TGA/DTA, microprobe, optical microscopy, XRD, XRF, etc. [ 1 – 10

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Central European Geology
Authors: Szabolcs Nagy, Sándor Józsa, Arnold Gucsik, Szaniszló Bérczi, Kiyotaka Ninagawa, Hirotsugu Nishido, Miklós Veres, Ákos Kereszturi and Henrik Hargitai

1993 Raman study of the high pressure behavior of forsterite (Mg 2 SiO 4 ) crystal and glass American Mineralogist 78 1143 1148

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overlay bands and thus improvement in the identification of the individual phases in the composition of the pottery [ 8 , 9 ]. Curve-fitting technique is also applied for spectral analysis [ 13 , 14 ]. Micro-Raman spectroscopy enables point

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Journal of Thermal Analysis and Calorimetry
Authors: Imre Miklós Szilágyi, Eero Santala, Mikko Heikkilä, Marianna Kemell, Timur Nikitin, Leonid Khriachtchev, Markku Räsänen, Mikko Ritala and Markku Leskelä

microscopy (SEM), FTIR, and Raman spectroscopy. Experimental section The AMT/PVP nanofibers were prepared by electrospinning a 1:4 mixture of aqueous solutions of PVP [(C 6 H 9 NO) n , 20 wt%] and AMT ((NH 4 ) 6 [H 2 W 12 O 40 ]· n

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Abstract  

C.V. Raman is being acknowledged by worldwide physics community for his classic works. The present study has made an effort to analyze how much impact in number of citation receiving for his publications. Of course, there was a lack of tools for such a study some years back. The study has limited to the database Science Citation Index for the period 1982–2005. The noteworthy results are: One third of his research papers have been cited at least once; The research papers published during 1918–1940 could make remarkable impact; Three of his papers have shown an upward growth in number of citations receiving; The total citations to papers of age 46 and 54 as on the year 1982 accounted for more than 50 per cent of the total citations received; Research works in the ‘Acoustics’ area have been cited more than any other area of his works; Eponymal citations are to be explored and analysed to understand the real impact of his works.

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Abstract  

The structural and thermal properties of three different dental composite resins, Filtek™ Supreme XT, Filtek™ Z-250 and TPH®3 were investigated in this study. The internal structures of uncured and cured resins with blue light-emitting diodes (LEDs) were examined by Micro-Raman spectroscopy. Thermal analysis techniques as DSC, TG and DTG methods were used to investigate the temperature characteristics, as glass transition (T g), degradation, and the thermal stability of the resins. The results showed that the TPH®3 and Filtek™ Supreme XT presented very similar T g values, 48 and 50°C, respectively, while the Filtek™ Z-250 composite resin presented a higher one, 58°C. AFM microscope was utilized in order to analyze the sample morphologies, which possess different fillers. The composed resin Filtek™ Z-250 has a well interconnected more homogeneous morphology, suggesting a better degree of conversion correlated to the glass phase transition temperature. The modes of vibration of interest in the resin were investigated using Raman spectroscopy. It was possible to observe the bands representative for the C=C (∼1630 cm−1) and C=O(∼1700 cm−1) vibrations were studied with respect to their compositions and polymerization. It was observed that the Filtek™ Z -250 resin presents the best result related to the thermal properties and polymerization after light curing among the other resins.

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Journal of Thermal Analysis and Calorimetry
Authors: M. Szelagiewicz, C. Marcolli, S. Cianferani, A. Hard, A. Vit, A. Burkhard, M. von Raumer, U. Hofmeier, A. Zilian, E. Francotte and R. Schenker

Abstract  

The use of hot-stage Raman microscopy — the direct coupling of Raman spectroscopy and thermomicroscopy — is demonstrated for the drug substances paracetamol and lufenuron.Paracetamol is a well-known analgesic and antipyretic drug, for which three polymorphic forms are currently known. Lufenuron is a benzoylphenyl urea derivative that has been classified as a chitin synthesis inhibitor. It is indicated for the use in pets for the prevention and control of flea population and used in crop protection for the control of Lepidoptera, Western Flower thrips and rust mites. It is the first time that the polymorphism of lufenuron is addressed. All known modifications of paracetamol and lufenuron were produced and identified by hot-stage Raman microscopy. A close correlation of thermal and spectroscopic information was achieved by this combination of techniques.For lufenuron a series of new polymorphic forms were found and characterized. Raman spectroscopy allowed to identify the thermodynamic stable form A as the one which is marketed in tablets.

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Abstract  

Dehydration of trehalose dihydrate implemented by slow heating (1 K min−1), has been monitored by Raman microspectroscopy from 25 to 110�C directly on single crystals. Between 90 and 120�C, gas initially trapped in irregular macroscopic defects, reorganizes to form spherical vacuoles. The Raman analysis of these vacuoles highlights that the areas in vicinity of the defects are the first affected by the dehydration mechanisms. Indeed, the progressive amorphization of the crystal starts around these defects.

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