مجله بلور شناسی و کانی شناسی ایران
سال هشتم شماره 2 (پیاپی 17، پاییز و زمستان 1379)

Crystal size and morphology of zeolite NaA have an important role in its specific use in the industries. Thus, investigation of parameters which influence crystal size and morphology of this compound during the synthesis is very important. Parameters such as intensi ty of mixing, temperature and aging time of the gel preparation, crystallization temperature and composition ratios are I"m portant I"n t hI"S case. In thI"s stu dy , t he I"n fl uences 0 f SiO0, chr('39') -N:-."",a""O,,- anu. 1 H2.0 ratI.o s an d I"I npW"l"ty" In t he ge I compoAshit.i o1n Al,O, Al20, on zeolite NaA crystal size and morphology are investigated. Characterization techniques such as X-ray Diffraction (XRD) and Scanning Electron Microscopy (SEM) have been used for phase identification, particle size and morphology of crystals throughout this work.

During the excavations of Tappeh Ghalaychi near the city of Bukan in west Azerbaijan province, a number of iron and bronze objects were found that are belonged to the 8th century B.C. The corrosion of iron objects were studied after chemical analysis. As these objects have a very high cultural value, chemical analysis by using destructive methods is not possible, therefore scanning electron microscope with energy dispersive X-ray microanalysis (SEM·EDX), which allows analysis without any damaging the Objects, was used. Likewise for analyzing the corrosion area of the metal objects, Fourier transform infrared (Ff-IR) spectroscopy and X-ray diffraction (XRD) were also used. The results of this research showed that a layer of magnetite which is covered with a layer of hematite exists at the surface of the iron Objects. In addition, wuestite and goethite were identified in the corrosion products layers.

The protons on a silica or alu mina su rface can be replaced by manganese( III) porphyrin ca tions, Mn(TPP +). Manganesc(III) porphyrin supported on silica and alumina can activate dioxygen in the presence of additional NaBH4 o r [NBu41rBH41 as an electron source and styrene, affording I-phenyl ethanol and acetophenone in a 4:1 ratio. When oxidation was applied in a mixture of benzene/ethanol, Mn(TPP+) heterogeneous catalyst was desorpted from silica and alumina surface. The oxidation of styrene has also been studied in two phases systems H20/CH2CI2 in the presence of NaBH4 and tetra-n-hutyl amonium bromide as a phase transfer catalys t. Manganese(III) porphyrin remained stable and major product was I - phenyl ethanol, when dichloromethane used in the presence of catalyst supported on alumina, the only product was I - phenyl e thanol.

Zonous Kaol ini te bea ring c lay de pos it is made by hydrothermal alteration of volcanic rocks mainaly of andesite ami dacite. Kao linit e , quartz and calci te are the main mineral co mposi tions. As quart z in the volcanic roc ks is cryptocrys talline, it is too dificult to seperat e it from kaol inite. The phys ical properties and chemica l composition of Zonous ceramic grade kaolinite bearing clay are directly related to its nature and geOlogical formation. The percenl age of SiOz in Zonous clay is highe r but the amount of Alz0 3 is lower th an Diamond kaolinte. For th is re ason the ceramic products of zonous cl ays have lower resistance to thermal shocks and modul e of rupture. High roughness, low plsticity and possible greater deformation during firing (Production of Ceramics) are o ther reasons for lim it ing the use of Zonous ceramic grade clays. The percentage of calcium oxide (CaO) in Zo no us clay is higer in co mparison wi th Diamond Kaolin hut pot asium oxide (KzO) whi ch plays as a nux in ceramic products is lower in zonous. The high pereentage of CaO which has a high melting point can raise the viscosity as a result lead to Crack in ceramic products. Fin ally with these colour pro pe rties, the Zonous ceramic grade kaolinite bearing clays , can be used as a fill er in pape r, paint and rubber industries.

In this research, poly halogene-chalcogene SeCI2lCI was synthesised and the crystal structure was determint:d by !l singk ;ryslal X-ray diffraction method. This compound formed at temperature ranges from 70-1S00C as ruby-red color and crystallizes in monoclinic crystal sys tem, space group P2t/c with 4 molecules per unit cell. Lattice parameters of the compound are:a = 6.088 A b = 6.555 A c = 16.032 A a=y=90° f3 = 98.02° v = 633.5 Achr('39') In addition, n .T.A analysis of SeCI2ICI crystals at tempe rature ranges from _70°C to 194°C and IR studies in the lower range of 700cmchr('39')} and Raman studies in the lower range of SOOcm·1 were also carried out.