A volcanic rocks sequence which is composed of stratoid trachyandesite, basaltic trachyandesite lava flows and interbeds of paleosols is cropping out in the northeast of Zarjebostan area, as a part of Alborz paleogene volcanic belt. Petrographical evidences such as Sieve textures, crystal zoning in the plagioclase phenocrysts and present of rounded phenocrysts all are indications of disequilibrium between the preexisting crystals and refreshed magma. Geochemical data from the studied volcanic sequence such as increase in the abundance of incompatible elements and concordant decrease in compatible ones are an indication of a magmatic evolution from bottom to top.

IntroductionPeanut (Arachis hypogaea L.) is an annual plant of the legume genus that is cultivated in 109 countries due to its high-quality oil and seed protein. In Iran, this crop is cultivated on an area of 3000 hectares, with an average yield of 4 tons per hectare. Threshing performance significantly affects seed loss and physical damage, including cracking and crushing of seeds during harvest. Therefore, over the last century, extensive research has been conducted on different types of threshing methods, as well as the design and development of various threshing machines.Research on seed crops such as cereals and seeds suggest that factors such as the rotational speed of the thresher, threshing-concave distance, feeding rate, and shape of threshing teeth play a crucial role in determining the threshing efficiency and quality of the threshed seeds. Although limited research has been conducted on peanut threshing, there are currently no combine-machines available for this crop on global markets. Therefore, this study aims to investigate several working parameters of an experimental peanut thresher, including the effect of Sieve angle, Sieve range of movement, and suction speed on the separation unit.Materials and MethodsThe relevant experiments were conducted in the Parsabad Moghan region of Ardabil province (latitude 39.65 North, longitude 47.91 East). To conduct the experiments and separate the seeds from the pods, we used a peanut threshing machine cultivar Nc2, which is commonly cultivated under agricultural conditions in Ardabil and Gilan Agricultural Research Centers.To achieve the aims of this research, we investigated several effective parameters in the performance of the machine, including Sieve angle, Sieve movement range, and fan suction speed, to obtain the best settings for maximum threshing performance and separation efficiency. It is worth noting that the average seed weight per kilogram of peanut plant was between 300-400 grams, and the moisture content of the seeds in the tested cultivar was 45%. Before using the machine, workers must first dig up the plants and place them on the ground in a coupe, after which another worker must feed the plants into the machine through the feeder.Results and DiscussionThe study found that changes in Sieve angle, Sieve movement range, and suction speed significantly affect the separation efficiency and peanut loss rate at a 1% significance level. Increasing the sieving angle leads to a higher speed of material movement on the Sieve, which results in insufficient time for separating straw from the seed. Similarly, increasing the Sieve movement range causes a rapid decrease in cleaning efficiency. To achieve better straw-seed separation, it is necessary to apply impact shocks to the products located on the Sieve within a short period. However, as the range of movement increases, the time interval between impact shocks also increases, which disrupts the straw's separation from the seed.The study found that increasing the Sieve range and suction speed leads to a higher rate of peanut loss. This is due to the fact that when the suction speed and Sieve movement range are increased, the product spends less time on the Sieve, which results in insufficient time for proper separation. Additionally, high speed may exceed the limit of peanut seed and cause it to move out of the machine with the straw. Increasing the Sieve movement range leads to a more uniform movement of straw and seed on the Sieve; however, achieving better separation of straw from the Sieve requires dynamic shocks and sudden acceleration, which decreases as the Sieve movement range increases. The optimal farm capacity and material capacity were achieved with a 5-degree slope at 0.55 hectares per hour and 509 kilograms per hectare, respectively, using a Sieve range of 3.5 centimeters and a fan suction speed of 8 meters per second.ConclusionThe study concluded that the Sieve movement range has the most significant impact on cleaning efficiency, while the Sieve angle has the least effect. Similarly, the Sieve movement range has the most significant influence on the rate of peanut loss, while the Sieve angle has the least effect.

Sieve tray CFD modeling with the assessment of k-£ Turbulence method and VOF framework has been considered in the current research work. Gas superficial fac- tor has been varied from 0.462 to 1.464 ((kg/m)0.5.s-1), while, the liquid flow rate changed from 17.8´10-3 (m3/s) to 6.94´10-3 (m3/s). Comparison between VOF and Eulerian methods proved that simulation error decreased from 16% to the only 2% for clear liquid height in different gas superficial factors. Moreover, this error was only 7% in comparison with 35% with the variation of liquid flow rates. These error values are obtainable when they are compared with the experimental data of Solari & Bell. Consequently, froth height has the good agreement with the mostly well known Colwell correlation. Interfacial area as the most important characteristic of the VOF has been investigated in this work and showed an increase from 0.18 m2 to 1 m2 with the increase of gas superficial factor to 1.464. The pressure profiles have also been investigated.

Tertiary andesitic basalts of the Sirjan area, Urmieh-Dokhtar Magmatic Arc, Iran, contain plagioclase phenocrysts enclosed in a matrix of amphibole, clinopyroxene and rare olivine crystals. Textural and compositional evidence suggests two significantly different types of plagioclase phenocrysts occur in the andesitic basalts. The most common type of plagioclase phenocrysts have zoning patterns that display abrupt fluctuations in An content (more than 20 mol %) that correspond to well-developed dissolution surfaces. The less common type of plagioclase phenocrysts is characterised by a core with Sieve texture, which is overgrown by oscillatory zoned rims. Changes in temperature, composition and H2O content of the surrounding melt caused the development of resorption zones in the engulfed plagioclases. In addition to the petrographical and mineral chemical evidences, Crystal Size Distribution (CSD) measurements show a kinked plot that reflects the effects of degassing and reveals mixing of two different phases of nucleation and growth. It is assumed that plagioclase phenocrysts originally crystallizing from the host magma were interrupted by mixing with a volatile-rich magma possessing low phenocryst content. The gradual loss of volatiles from plagioclase-saturated intrusive magma could be responsible for the Sieve-textured core.

Sieve trays are widely used in the gas- liquid contactors such as distillation and absorption towers. In this article, a three-dimensional, two phase CFD model using Euler-Euler framework was developed to simulate a distillation tower with two Sieve trays. Hydrodynamic simulation of air and water system in different rates of gas phase was carried out and velocity distribution parameters, clear liquid height and froth height were calculated and compared to the experimental data and the literature simulation result. Liquid velocity distributions on the two trays were found to be in relatively good agreement with experimental data. It was found that heights of accumulated liquid in the down-comers are not equal.

Zeolites due to their structures can be used as molecular Sieves for purification of materials and solutions. Zeolites with PHI and SOD structure are so common and applicable for this purpose. Hydroxy sodalite and phillipsite are the more abundant members of zeolites which display good selectivity for very small molecules and some ions such as Sr, Pb, Zn, Cu and Rb. There is not any pure natural deposit of these zeolites and purify methods are not cost-effective. Therefore, introducing an effective method to prepare these zeolites is necessary. In this study, hydroxy sodalite and phillipsite have been synthesized respectively from clinoptilolite and volcanic ash at hydrothermal conditions in the presence of alkaline solutions. Mineralogical studies show that K, Na and Cl ions are necessary in SOD and PHI structure. The effect of K+ concentrations and temperature in the presence of constant value of Na+ and Cl- are being considered as the variable parameters in the present experiment. NaCl used as source of Na+ and Cl- ions. Alkaline solutions were prepared by using 2 to 12 grams KOH powder and synthesize mixture were heated at temperatures of 100 and 150oC. Results of this study show that phillipsite is synthesized at 100 and 150oC in all runs. Hydroxy sodalite is appeared just in 150oC by using clinoptilolite as initial material. Analcime formed as by-product of volcanic ash phase transition at 150oC.

Distillation Column is one of the eldest and important separation equipments which many new designs and various changes in its internals are still being made for increasing its performance. In this research with utilizing computational fluid dynamics, Sieve tray hydraulics in experimental scale has been simulated in two phase and three dimensions in Eulerian frameworks by FLUENT 6.3 commercial software. And the simulation have been validated with Krishna et al. (1999) experimental and simulations results. Then simulating with RSM and k-e in three forms of Standard, Realizable and RNG turbulence models, the results have been discussed and compared and has been demonstrated that the RNG model predicts lower clear liquid height which are closer to the experimental results.

Separation of nitrogen from a gaseous mixture is required for many industrial processes. In this study, the adsorption of nitrogen on zeolite 4A was investigated in terms of different adsorption isotherm models and kinetics. An increase in the initial pressure from 1 to 9 bar increases the amount of adsorbed nitrogen from 6. 730 to 376. 030 mg/(g adsorbent). The amount of adsorbed nitrogen increased from 7. 321 to 40. 594 mg/(g adsorbent) by raising the temperature from 298 to 333 K at a pressure equal to one bar; however, it then dropped to 15. 767 mg/(g adsorbent) when temperature decreased to 353 K. Increasing the amount of the adsorbent from 1 to 4 g decreased the specific adsorption from 67. 565 to 21. 008 mg/(g adsorbent) at a temperature of 298 K and a pressure of 3 bar. Furthermore, it was found that the nitrogen adsorption experimental equilibrium data are consistent with Sips and Langmuir-Freundlich models. The highest overlap was achieved through second order and Ritchie’ s models.