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., 2009; Kaszab et al., 2017 ). The properties of honeys also vary according to their exposure to heat. Heat treatment of the honey can influence its composition and physicochemical properties ( Bodor et al., 2019; Božiková et al., 2018 ). The proper

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Journal of Thermal Analysis and Calorimetry
Authors: J. Bajdik, K. Pintye-Hódi, Cs. Novák, P. Szabó-Révész, G. Regdon, I. Erős, and G. Pokol

Abstract  

Dimenhydrinate is a heat-sensitive antihistamine with a low melting point. The heat-sensitive feature is of importance if direct compression is used. Direct measurement of the heat originating in the texture of tablets during compression is very difficult. Thermoanalytical methods were used as indirect methods to describe the changes in material properties at high temperature: differential scanning calorimetry, thermomicroscopy and thermogravimetric analysis. Film coating method is widely used in pharmaceutical technology. A fluidized bed apparatus was applied to coat the crystals. The coating film forming agent was hydroxy-propyl-methylcellulose (HPMC), which is a gastric-soluble polymer. Thermoanalytical measurements reveal that dimenhydrinate crystals are sensitive to heat. Film coating method does not alter the shape of the DSC curve of dimenhydrinate, but increases the melting point. The presence of a macromolecular film reduces the thermal conductivity, because it separates the particles.

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Abstract  

In this study, the zeolitic tuffs having clinoptilolite obtained from Bigadic region of western of Anatolia, Turkey were investigated as regards to whether it is possible to be transformed into amorphous phase from them. At first, the zeolite tuffs rich in clinoptilolite were characterized using XRD, DTA, TG, DSC, and FTIR standard methods. All the samples were heated at 110 °C for 2 h and then were expanded within 5 min between the temperatures 1200 and 1400 °C. In addition, porosity and density were determined. The resistance values of all the samples were measured in acidic and basic media. These samples were also analyzed. As a result of this study, zeolitic tuffs in clinoptilolite were transformed into amorphous phase, and especially in chemical industry were found convenient.

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Abstract  

The uranium and thorium contents were evaluated in the 100–400 µm granulometric fraction of different sedimentary phosphate samples by using a method based on determining the mean critical angles of etching of the CR-39 and LR-115 type II solid state nuclear track detectors (SSNTD) for detecting -particles emitted by the nuclei of the uranium-238 and thorium-232 series. Data obtained were compared with the results of -ray spectrometry measurements performed on the same samples. The influence of the calcination and water washing treatments as well as the lithology and stratigraphy on the uranium concentration of the phosphate samples was investigated.

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Abstract  

Mechanochemical treatment (MChT) in various media (water, air, ethanol) of the V2O5/ammonium dimolybdate composition at the ratio V:Mo = 0.7:0.3 has been carried out. Physicochemical transformations in this system have been studied by means of X-ray powder diffraction (XRD) and thermal analysis as well as FTIR spectroscopy. Ammonium dimolybdate undergoes hydration with formation of 4-aqueous ammonium paramolybdate during the MChT in water. Changes of phase and chemical composition at activation are determined first of all by nature of medium in which milling was carried out. Maximal interaction of components occurs during modification of the studied system in water.

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Abstract  

We present real time vanadate (V5+ ) uptake imaging in acowpea plant by positron emitting tracer imaging system (PETIS). Vanadium-48was produced by bombarding a Sc foil target with 50 MeV -particlesat Takasaki Ion Accelerators for Advanced Radiation Application (TIARA) AVFcyclotron. Then 48 V was added to the culture solution to investigatethe V distribution in a cowpea plant. The real time uptake of the 48V was monitored by PETIS. We measured the distribution of 48Vin a whole plant after 3, 6 and 20 hours of V treatment by Bio-imaging AnalyzerSystem (BAS). After the 20 hour treatment, vanadate was detected at the up-groundpart of the plant. To know the effect of V uptake on plant activity, 18F-labeled water uptake was analyzed by PETIS. When a cowpea plantwas treated with V for 20 hours before 18 F-labeled water uptakeexperiment, the total amount of 18F-labeled water absorption wasdrastically decreased. Results suggest the inhibition of water uptake wasmainly caused by the vanadate already moved to the up-ground part of the plant.

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Abstract  

The effectiveness of the neutralization process on heavy metals precipitated in sludge has been evaluated using instrumental neutron activation analysis (INAA) facilities at the South African Nuclear Energy Corporation (Necsa). The elemental concentrations of Th, Fe, Ag, Co, Cr, As, Au and K were reduced after the neutralization process with the exception of Mn and Sn which appeared to be enhanced by the neutralization process. Even though the neutralization process was targeted at the basic ferric arsenate compound, it was found to be effective in reducing other elemental concentrations. The variations in the geochemical compositions of the sulphidic ores during treatment at various stages also showed that physical processing stages do not significantly alter the elemental concentrations in the feed materials, however, the chemically active processing stages do. Also, the enhancement of the elements at the chemical stages depends on total quality control, where the application was not very repeatable the pattern of variation of elements at some stages was found to be irregular irrespective of the ore grade. The elements; Sn, Fe, Th, K, Au, Ag, As, Cr, and Co were enhanced in almost all the chemically active stages. Au was much more enhanced during flotation and bio-oxidation processes. Correlation analysis performed to determine the distribution patterns show that Fe, As, Ag and Co are geochemically associated and might be enriched simultaneously.

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Summary  

A method has been developed for analyzing pyrite quantitatively in the sediments of Erhai Lake in southwest China using 57Fe Mössbauer spectroscopy combined with a series of acidic pre-treatments. Following a washing with an alkaline solution (0.1N NaOH), the sediment samples were successively treated using HCl, HF, and then HCl (65 °C). The residues thus prepared were analyzed for pyrite using 57Fe Mössbauer spectrometry. The presence of pyrite was also confirmed in the acidic residues of the sediments using sulfur K-edge X-ray absorption near edge structure. This method can be used to measure pyrite in aquatic sediments, especially when the concentration of pyrite is very low and the particles of pyrite are small or the crystallinity is low, and even in amorphous status. In addition, vertical variations of pyrite contents are positively correlated with organic matter and negatively correlated with hematite, superfine paramagnetic ferric iron and sedimentation rate in the cored sediment from the Erhai Lake. All these geochemical indicators may also reflect environmental changes in sedimentation conditions and diagenesis.

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. Technologies for olive mill wastewater (OMW) treatment: a review . Journal of Chemical Technology and Biotechnology 81 ( 2006 ) 1475 – 1485 . [25] T. Akar

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Journal of Thermal Analysis and Calorimetry
Authors: Lucjan Chmielarz, Małgorzata Rutkowska, Piotr Kuśtrowski, Marek Drozdek, Zofia Piwowarska, Barbara Dudek, Roman Dziembaj, and Marek Michalik

should be noted that this absorption band is absent in the spectrum of as-synthesized hydrotalcite, so the thermal treatment (darker, nearly black color of the sample) results in a partial oxidation of Co 2+ to Co 3+ . Probably, the increased calcination

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