Number 41 Volume 13

Open Access Article

1 - Si Adsorption on the borne phosphide honey-combe structure
Hamidreza Alaei Mahnaz Joorabloo

In this work, based on the Density Function Theory we studied the Borne Phosphide honey-combe structure and for comparing the dimensionality effects, we performed a brief study about its three-dimension (bulk) too. Theses first-principles calculations obtained an indire More

In this work, based on the Density Function Theory we studied the Borne Phosphide honey-combe structure and for comparing the dimensionality effects, we performed a brief study about its three-dimension (bulk) too. Theses first-principles calculations obtained an indirect band gap for 3D of Bp where it obtained one direct (about 0.9024 eV) for its honey-combe structure that is transparent for vertical polarization beam with a selection ability in transmitance/ adsorbance and reflectance for horizontal polarization. The obtained band gaps are near to repports. As a new work, by adsorption of Si at four outstanding positions on the honey-combe structure of Bp we studied its electrical and optical propertis where the omitting of band gap and pseudo-metaling of structure was a superior result for Si adsorption. for improvement of calculation results we used the Modified Becke–Johnson potential proposed by Tran and Blaha (TB-MBJ). Manuscript profile

Open Access Article

2 - study of dithioglyoxal conformations and how it is formed from 1, 2-ditate by DFT method
vahideh hadigheh rezvan

1, 2-Dithiete is a cyclic and unsaturated compound. This organo sulfuric compound can be converted to di-thiolene (dithioglyoxal) which is its valence isomer. Conversion reaction of 1, 2-dithiete to di-thiolene, structural properties, polarity, and polarizability of som More

1, 2-Dithiete is a cyclic and unsaturated compound. This organo sulfuric compound can be converted to di-thiolene (dithioglyoxal) which is its valence isomer. Conversion reaction of 1, 2-dithiete to di-thiolene, structural properties, polarity, and polarizability of some derivatives of these two valence isomers was examined by quantum mechanical method at the level of DFT/LSDA theory and bases sets 6-311 ++ g (d, p) using computational program Gaussian. The conversion of 1, 2-dithiete to di-thiolene takes place through the S-cis conformation pathway and is a exothermic reaction. For di-thiolene, two conformations, S-cis and S-trans, were obtained. The S-trans conformation is more stable. In the case of ten derivatives (R = CH3, CF3, Cl, CN, OCH3, CH2CH3, t-Bu, Cyclopropyl, Cyclobutyl, and Cyclopentyl) the S-cis conformations are so unstable that they are not obtained as local structures. In general, S-trans di-thiolene are more stable than their cyclic valence isomers, 1,2-dithietes. Of course, the degree of stability depends on the type of substituent. Manuscript profile

Open Access Article

3 - Calculation of optical properties of Na2S in different phases
Hamdollah salehi Emel Abdoullahi

In this paper, the optical properties of Na2S in various fcc, orthorhombic and hexagonal structural phases have been investigated. Calculations have been performed by using wien2k package which is based on density functional theory and FP-LAPW method. The LDA band struc More

In this paper, the optical properties of Na2S in various fcc, orthorhombic and hexagonal structural phases have been investigated. Calculations have been performed by using wien2k package which is based on density functional theory and FP-LAPW method. The LDA band structure calculation indicate that Na2S is a direct band gap semiconductor in each three studied phases. The optical band gaps obtained from imaginary part of dielectric function are in good agreement with structural band gaps. According to our results the maximum peak of the imaginary part of dielectric function, occurred at the energy range which coincide to the maximum peak of obsorbation and extinctions curves on that range. Similar behavior is observed for real part of dielectric function in comparison to refraction and reflections diagrams. Manuscript profile

Open Access Article

4 - The production of activated carbon from polyethyleneterephthalate (PET ) bottle waste and its use to absorbtion iron (III) from water
فرخنده اوشال Saeed Jamehbozorgi Mojdeh Liaghati

Abstract: In this research, Initially, activated carbon was prepared using PET waste bottles and the activated carbon was detected using FTIR, BET and SEM analyzes. In the next step, the adsorption of Iron (II) metal ions on the synthesized activated carbon was performe More

Abstract: In this research, Initially, activated carbon was prepared using PET waste bottles and the activated carbon was detected using FTIR, BET and SEM analyzes. In the next step, the adsorption of Iron (II) metal ions on the synthesized activated carbon was performed discontinuously.The effects of variables such as initial concentration of Iron, temperature, pH and time were investigated and the results showed that the optimum amount of Iron ion adsorption in 100 ppm solution with a pH of 5 and a contact time of 60 minutes and an adsorbent amount of 0.2 g occurs. Isotherms were studied using Langmuir, Freundlich and Tamkin models and adsorption kinetics using first and second order pseudo-second order models. It was observed that the behavior of the desired process follows the Langmuir, isotherm and its kinetics corresponds to the pseudo- first order reaction. Manuscript profile

Open Access Article

5 - Investigating the effect of external electric field on the neurotransmitters acetylcholine, dopamine, GABA, glutamate and serotonin using density functional theory method
M|ohammad Erfan Zand Mohammad Reza Bozorgmehr Mohammad Momen Heravi Safar Ali Beyramabadi

Today, the nervous system is exposed to various electric fields caused by the use of various electronic devices such as mobile phones. On the other hand, the effect of these electric fields on the nervous system is not known and research in this field is important. In t More

Today, the nervous system is exposed to various electric fields caused by the use of various electronic devices such as mobile phones. On the other hand, the effect of these electric fields on the nervous system is not known and research in this field is important. In this article, the effect of applying an electric field on some of the most important neurotransmitters of the nervous system has been investigated by the method of density functional theory. For this purpose, the structure of neurotransmitters acetylcholine, dopamine, GABA, glutamate and serotonin were optimized with B3LYP level and 6-311++G** basis function. Then electric fields with different intensities from 0.001 to 0.01 AU in steps of 0.001 were applied to them. Structural parameters and quantum descriptors such as electron affinity, ionization energy, chemical potential, hardness, electronegativity and electrophilicity of neurotransmitters were calculated. Also, the partial charge change of their constituent atoms in the presence of different electric fields was investigated. The results show that the lowest contribution of charge changes is in hydrogen atoms. In general, with the increase of the electric field, the electronegativity increased, and the chemical potential and electrophilicity decreased. Manuscript profile

Open Access Article

6 - Steps, calculations and results of studies of theoretical predictions of quantitative structure retention relationship (QSRR) of Pittosporum undulatum essential oil
مجید محمدحسینی مهدی نکوئی

In this article, a detailed description of the linear models capable of predicting the inhibition indices of a large group of natural compounds identified in the essential oil of Pittosporum undulatum, as one of the medicinal plants, has been discussed. In this regard, More

In this article, a detailed description of the linear models capable of predicting the inhibition indices of a large group of natural compounds identified in the essential oil of Pittosporum undulatum, as one of the medicinal plants, has been discussed. In this regard, the work is based on quantitative structure retention relationship (QSRR), which is of prime importance in scientific resources to establish a logical and meaningful relationship between the Kovats index as a dependent variable and a group of molecular descriptors as independent variables. In this regard, after drawing the structure of the natural compounds using the Hypercam software and optimizing their molecular structures, Dragon software was used to extract the relevant molecular descriptors. In the next step, after removing irrelevant and redundant descriptors, a group of important and effective descriptors were identified and their linear relationship with the Kovats retention index was discussed and investigated using stepwise multiple linear regression method as well as another variable selection method based upon genetic algorithm feature selection approach. The obtained results indicate the high capability of the presented models to predict the Kovats index of a wide group of natural compounds. Manuscript profile

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