JOURNAL OF SCIENCES (ISLAMIC AZAD UNIVERSITY)
Year:2001 | Volume:11 | Issue:40|Papers Count:12

In this work the synthesis and characterization of solid state m-dioxobridged complex of molybdenum (V) with ethylenediamine -N,N'-diacetic acid, [MO2 O4 (EDDA)2]2- is described. The occurrence of Mo=O stretching modes in the region, between 900-1000 cm-1, as well as the lower frequency, widely split bands between 864 and 478 cm-1, are characteristic of a m- oxobridged complex in the solid state. Proton NMR, IR and Electronic Absorption Spectra of the complex are described.

One of the most important problems in Economics, Industries and other fields of science is assignment problem. This problem is concerned with assigning the jobs to machines by the minimum cost. In standard assignment problem, there is one cost for each allocation. The real world assignments are too complex to consider only one cost to each, allocation. In this paper, the assignment problem with several non-homogeneous costs is introduced and a solution method by using data envelopment analysis is suggested.

In this research, aqneous Solution equilibria of system ''VO2 -+glycine" has been studied, in a pH range of 1.3 to 9 and high ligand to metal ratio by a combination of potentiometric and spectrophotometric method. The ionic strength was maintained at 1.0 mol dm-3 with sodium perchlorate. In these conditions, two complexes VO2L and VO2L2 are formed, while L represents fully dissociated amino carboxylate anion. The Stability constants for the considered complexes have been determined at 25, 30 and 35C°. Then the thermodynamic values (DG°,DH°,DS°) were calculated from these values and their variations with temperature. The Protonation constant of glycine, K1H, was also determined potentiometrically under the same codition and the thermodynamic values of protonation (DG°,DH°,DS°) were then estimated by the same procedure.

Acetonitrile with good transparency in short- wavelenght UV, is used as the mobile phase for HPLC. Impurities such as acrylonitrile, allyl alcohol, benzene, propionltrile, H2O, etc, removed from commerical grade acetonitrile. First by KMnO4 oxidation at 325-328 k and seperated by distillation method at atmospheric pressure. Distillation is canducted at reflux ratio 20-30 :1. hen by passing through packed columns of activated charcoal and acid Al2O3 activated at 573 k for 4h. The efficiency of purification was primely evaluated by measuring the UV absorbances. Then by capillary gas chromatography was assayed.

Catalytic behaviour of Mechanically mixed oxides NiO, La2O3 in Partial oxidation of methane to synthesis gas was studied. Then LaNiO3 Compound with perovskite structure was synthesized by different methods.The perovskite structure was characterized by powder X-ray diffraction and elemental analysis. The morphology of synthesized crystals was studied by SEM method.Catalytic behaviour of perovskite was studied in partial oxidation of methane to synthesis gas. The activity and methane conversion in presence of both catalysts were studied and the surface areas of the catalysts were measured by BET method.

In this research, the ability of growth, changes in heterocyst frequencies, and pigmentation of Nostoc sp. in response to low light energy (20,30,40,50 and 60 mmol quanta m-2s-1), light dark duration (12/12), and complete darkness (with galactose; sucrose or fructose) were studied. Results showed that, in 40 mmol quanta m-2s-1), a considerable lag phase in growth curve exists. Phycoerythrin was more efficient in light adaptation than phycocyanin light / dark durations caused a noticable decrease in heterocyst frequency. The ability of growth and heterocyst production completely blocked in dark in the presence of galactose and sucrose but in the presence of fructose this ability was slightly observed.Heterocyst frequency was reduced efficiently and significantly: even after 5-minute exposure of UV-C. The ability of recovery was not seen in this species. The content of phycoerythrin reduced considerably in relation to exposure time.

According to the importance of investigated tropane alkaloides in pharmaceutical and deffensive industrial, Datura stramonium was studied in this research. The seed was prepared from forests research institute. The beginning of biosynthesis and changing rate of tropane alkaloides in vegetative phase and reproductive phase was done by using T.L.C, spectrophotometery, H.P.L.C and Gc/Ms methods.The results of yeild extracts analysis in vegetative phase were observed that tropane alkaloid production have been begun at the end of 2nd week of seed germination and it will be ascending at the and of the 10th week. It was specified that MS (0.5 NAA mg/lit) medium is the best leaf explants callus production. The leaf was divided in to three parts as basic, meidiative and topical for leaf explant preparation. Each one of the leaf explants producted different callus. The cytolgical examination with L.M and E.M (T.E.M & S.E.M) and cytochemical studies with dragendrov indicator, was identified idioblast cells in to semiclear calli leaf stem and petiol.

Staphylococcal enterotoxin B (SEB) as a superantigen and as a food intoxication agent causes rapid and waste pathophysiological changes in the body by its powerful stimulation of the immune system. The present study examined some of the histopathological effects of inhalation SEB in Grivets monkey. Such studies cold help the medical center to find the better treatment method of intoxication. In test chamber, monkeys were exposed to pure SEB for 15 minutes by a nebulizer. Then experimental and control moukey's lunges showed that the profound edema in alveoli and also the thickness and activation of alveolar septum and also lymphatic follicles and air-waies epithelial necrosis was recognized. This result showed significant different P<0.05 in comparison with control animal.

The study area is situated in the Nakhlak Mountains (NE Anarak, Central Iran) at the western margin of the Central Iran desert. The Triassic rocks of the have a thickness of 2701 meters, and are divided into 3 Formations: Alam Formation, Baqoroq Formation and Ashin Formation that have been dated by Ammonoida fossils. The mentioned Ammonoids belong to a single bio-district and may be compared with Aghdarband Ammonoids. This similarity shows that the location of Triassic rocks in Nakhlak area was adjacent to the Aghdarband area, at the time of the formation of Southern margin of Turan continent. On the other hand, the Paleobiogeographical relationships of Triassic Ammonoids in Nakhlak area with other areas, show the existence of a certaiu province in the Southern margin from the Eastern most to western most portion of paleothetys ocean. This distribution also shows the bio-district distinction of Lurasia continent (to the north) from Gondwana (to the south).

To study the storm deposits of the lower part of the Elika Formation (Lower Triassic), six stratigraphic sections in Central and Eastern Alborz were selected. the thickness of the lower part of the Elika Formation in the study area ranges from 95 to 196 meters.The storm deposits have sharp or erosional bases and are interbedded with fair-weather non-storm deposits. In this paper, based on the mode of formation, the storm fades have been divided to usual and unusual storm deposits.Usual storm fades, based on relative depth variations, have been deposited in shorline, proximal open marine and distal open marine environments. The most important characteristics of these fades are the presence of a basallag deposit, graded bedding, horizontal laminations, hummocky cross stratification and escape traces. Lateral and vertical fades variations indicate that the thickness, grain percentage and their grain size decrease but intensity of bioturbation, frequency of wave ripples, laminated layers and gutter casts increase from proximal to distal open marine environments. These variations are very important for recognition of various sequences of the lower part of the Elika Formation.The unusual storm fades consist of (a) Flat pebble intraformational conglomerate and (b) Intraclastic hematitic gastropod packstone/grainstone, that were depostited in mid ramp.