Authors:S. Khalameida, J. Skubiszewska-Zięba, V. Zazhigalov, R. Leboda, and K. Wieczorek-Ciurowa
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.
Authors:M. Misdaq, Y. Ouahidi, S. Fakhi, J. Lamine, A. Bakhchi, A. Yves, M. Azouazi, J. Abbe, and M. Benmansour
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.
Authors:J. Bajdik, K. Pintye-Hódi, Cs. Novák, P. Szabó-Révész, G. Regdon, I. Erős, and G. Pokol
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.
Authors:E. Yörükoğulları, G. Yılmaz, and S. Dikmen
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.
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.
Authors:G. Zheng, K. Suzuki, Y. Takahashi, H. Shimizu, A. Kuno, and M. Matsuo
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.
Authors:J. Gbadago, A. Faanhof, C. Schandorf, and E. Darko
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.
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
Authors:W. Ciesińska, J. Zieliński, and T. Brzozowska
Coal-tar pitch was modified by addition of polystyrene, poly(ethylene terephthalate), unsaturated polyester and coumarone-indene
resin. The optimum conditions for production of homogeneous binary pitch-polymer blends containing 10% w/w of the polymer were established. Softening points, contents of toluene and quinoline-insoluble matters and rheological properties
of the blends were determined. The yield of solid fraction in semi-coking the blends was also found. The effect of polymers
on the coal-tar pitch blend properties was evaluated. Some pitch-polymer blends were then carbonized to carbon sorbents used
for purification of water and wastewater.
Authors:N. Cohen, M. Odlyha, D. Ucko, and Q. Pankhurst
Mechanical alloying is a versatile technique for the solid state synthesis of many materials, including alloys such as iron-copper
where the elements are immiscible under equilibrium conditions. The structural and magnetic state of these alloys, and their
thermal stability, have been investigated by means of thermomagnetometry, DSC, X-ray diffraction and Mssbauer spectroscopy.
Comparison of the thermomagnetometry curves for the various alloys together with analysis of intermediate reaction products
enabled the individual thermal processes to be identified. The Curie temperature of the alloys was measured, and it was found
that on heating the metastable alloys underwent phase segregation between 300-400C.