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Abstract  

Chemical factors such as pH, concentration and temperature affecting the removal of UO2 2+, Th4+, Fe3+, Cu2+, Pb2+,Cd2+, Ni2+, MnO4 - and phenol by Eichornia crassipes aquatic plant from their solutions were examined. Maximum uptake of ions by Eichornia crassipes occurred at pH 4 to 6±0.5 at 25±3 °C. An initial rapid uptake phase for the first 6 hours followed by a slower near linear one was observed. One gram of Eichornia crassipes can accumulate about 25 mg UO2 2+, 5 mg Th4+, 30 mg Fe3+, 10 mg MnO4 -, 15 mg Cu2+, 1.0 mg Pb2+, 1.5 mg Ni2+, 0.7 mg Cd2+ and or 25 mg of phenol.

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Abstract  

Selenite was boiled in KCl solutions of different concentrations at the respective boiling temperatures and atmospheric pressure. The products were subjected to X-ray diffraction analysis, qualitative infrared analysis, differential thermal analysis and microscopic examination. The product obtained in 1.0 M KCl solution was the -form of calcium sulphate hemihydrate (-CaSO4·0.5H2O). In more concentrated KCl solution (1.5, 2.0, 2.5, 3.0, 3.5 or 4.0 M), the -form of calcium sulphate hemihydrate (-CaSO4·0.5H2O) was formed, and a reaction took place between KCl and CaSO4, which gave a double salt: potassium pentacalcium sulphate monohydrate (K2SO4·5CaSO4·H2O).

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A review is given of various metallurgical problems treated in the author's laboratory, for which quantitative calorimetry gave very valuable information. Measurements of thermodynamic data for phase diagram calculations, vacancies in ordered alloys, annealing of steels, and the recovery and crystallization of amorphous alloys are successively examined.

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Abstract  

The crystallization behaviour of amorphous melt spun Fe82−x−yCr18ZrxBy (x=0–8, y=10–20) ribbons have been investigated using differential scanning calorimetry. The crystallization temperature and crystallization behaviour change with varzing Zr and B content. The microstructural development during annealing of amorphous Fe64Cr18Zr8B10 has been investigated by a combination of transmission electron microscopy and energy dispersive X-ray microanalysis. Isothermal annealing for 2 h at temperatures in the range 600–1000°C produces a variety of different microstructures depending on the annealing temperature. At 600°C, the amorphous alloy partially crystallizes to a form a microstructure consisting of 9 nm sized bee ferrite grains embedded in an amorphous matrix. At temperatures in the range 700–900°C, the alloy microstructure transforms into a mixture of bee ferrite, faulted fcc MB12 boride particles and tetragonal M3B boride particles. At 1000°C, the faulted fcc MB12 boride particles are replaced by orthorhombic M4B boride particles.

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Abstract  

The influence of radioactive krypton85Kr on the surface properties of poly(3-pentylthiophene) has been studied. Irradiation by gaseous85Kr leads to structural polymeric chain changes, which induce after iodine doping the formation of charge-transfer complexes with iodine as well as with gaseous sulfur dioxide manifesting itself by the increased electric conductivity. The presence of ammonia brings about reaction with iodine bound in the complex with a conducting polymer.

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Abstract  

Nuclear chemistry is usually associated with great disasters, especially the atomic bomb; this without reflecting that knowledge of nuclear chemistry has also had many benefits in the field of medicine and health. Whereas in technologically advanced countries, nuclear chemistry is considered to be an important part of the syllabus, including topics such as radioactivity with the emphasis in making conscience in the common citizen of the inherent benefits.

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