در هنگام جستجو کلمه در قسمت عنوان میتوانید کلمات مورد جستجو را با کاراکتر (-) جدا کنید.
کاربرد نوع شرط:
- جایگاه : پژوهشی
- مجله: Geopersia
- نوع مقاله: Journal Article
- کلمات کلیدی: Iran,Multivariate analysis,Hydrochemical data,non-thermal springs,thermal springs
- چکیده:
- چکیده انگلیسی: In this study multivariate statistical analysis are used to characterize relationships between hydrochemical properties of
thermal and non-thermal springs. Four factors for thermal waters and two for non-thermal springs were extracted based
on factor analysis. In thermal springs, the first factor showed high loading on Ca, Mg, Na and K and this factor was
interpreted as leaching of cations in the rocks by meteoric thermal water. The second factor showed high loading on SO4
and it was assumed to be extracted from gypsum dissolution. The third factor showed loading on HCO3 and it was
interpreted to be caused by dissolution of limestone. The forth factor showed high loading on SiO2 and it was supposed to
be result of alteration of silicate minerals. The δ18O-enrichment with respect to the meteoric water line (MWL), confirms
that thermal waters have been diluted by shallow waters with meteoric origin. Comparison of the chemistry of thermal
and non-thermal springs and other evidences are indicative of an immature hydrothermal water system in Mahalat.
Quartz and Chalcedony geothermometery show the range of 96oC to 131 oC temperature for the Mahalat reservoir.- انتشار مقاله: 21-11-1391
- نویسندگان: Feridon Ghadimi,Mahmoud Mirzaei,Mohammad Ghomi
- مشاهده
- جایگاه : پژوهشی
- مجله: Journal of Nanoanalysis
- نوع مقاله: Journal Article
- کلمات کلیدی: Adsorption,Density functional theory,Vitamin C,Fullerene
- چکیده:
- چکیده انگلیسی: Density functional theory (DFT) calculations were performed to investigate adsorptions of vitamin C (Vit) on the surface a fullerene structure (Ful) in gaseous and water–solvated systems. Two models of Vit including OVit and MVit were created based on the original structure of Vit for OVit and methylation of all hydroxyl groups for MVit. All singular and hybrid structures were optimized and the molecular properties were then evaluated for them. Binding energies and dipole moments indicated that the formation of MVit–Ful hybrid could be more favourable than OVit–Ful hybrid. Molecular orbital properties of hybrid systems demonstrated almost similarity to each other and similarity to the singular Ful model; however, they are completely different from both of singular Vit models. It could be mentioned that the Vit counterparts miss their contributions to molecular orbital distributions in the hybrid systems. Quadrupole coupling constants (CQ) have been also evaluated for oxygen atoms of Vit counterparts in both singular and hybrid models, in which they demonstrated the effects of interactions on the atomic scale properties of Vit counterparts. The evaluated results indicated the solvent effects on all molecular and atomic scales properties of Vit and Ful structures in both of singular and hybrid situations.
- انتشار مقاله: 14-04-1396
- نویسندگان: Rezvan Baniasadi,Kun Harismah,Maryam Sadeghi,Mahmoud Mirzaei
- مشاهده
- جایگاه : پژوهشی
- مجله: Journal of Medicinal and Chemical Sciences
- نوع مقاله: Journal Article
- کلمات کلیدی: Density functional theory,Phthalocyanine,Photosensitizer,Singlet molecular oxygen
- چکیده:
- چکیده انگلیسی: In this work, phthalocyanine and its OCH3 derivatives were investigated to see their photosensitization characteristics for producing singlet molecular oxygen, which is important in photodynamic therapy type-II. All structures were first optimized to achieve the minimized energy 3D models Subsequently, they were prepared for the photosensitization investigations. All the experiments were conducted based on the density functional theory calculations. The energy absorption and emission observed between the occupied and unoccupied molecular orbitals based on the required energy for excitation and the corresponding energy of emission. The results indicated that the OCH3 models could be expected to be safer than the original phthalocyanin by their required energy at longer wavelengths. The ratio of singlet molecular oxygen generation was found to be 1:1 for each of the OCH3 derivatives.
- انتشار مقاله: 21-02-1398
- نویسندگان: Ali Zare,Mahmoud Mirzaei,Mahboubeh Rostami,Elham Jafari
- مشاهده
- جایگاه : پژوهشی
- مجله: International Journal of Nano Dimension
- نوع مقاله: Journal Article
- کلمات کلیدی: Density functional theory,Tautomer,Pyridinone,Quadrupole coupling constant
- چکیده:
- چکیده انگلیسی: Density functional theory (DFT) based calculations have been performed to examine the relaxations of tautomers of 4–hydroxy–6–methylpyridin–2(1H)–one (MPO), as a representative of pyridinone derivatives, at the fullerene (C60) surfaces. Optimized molecular properties including energies, dipole moments and atomic scale quadrupole coupling constants (CQ) have been evaluated to investigate the structural and electronic properties of the models. The structural configurations of tautomers show different relaxations at the C60 surface yielding different magnitudes of total and binding energies. Moreover, deformation of each tautomer due to relaxation at the C60 surface with respect to the initial singular structure has been examined. Complimentary parameters of energy gaps and dipole moments exhibit the effects of relaxations at the C60 surface for the MPO counterparts. Atomic scale CQ properties also indicate that the electronic properties of atoms show significant changes for tautomers and hybrid systems. As a final note, the tautomeric structures in singular and hybrid forms exhibit different electronic properties because of effects of interactions with C60, especially for the interaction regions.
- انتشار مقاله: 24-09-1395
- نویسندگان: Elahe Naderi,Mahmoud Mirzaei,Lotfollah Saghaie,Ghadamali Khodarahmi,Oguz Gulseren
- مشاهده
- جایگاه : پژوهشی
- مجله: International Journal of Nano Dimension
- نوع مقاله: Journal Article
- کلمات کلیدی: Graphene,Nitrogen,aluminum,Phosphorus,Density functional theory (DFT),Boron
- چکیده:
- چکیده انگلیسی: Stabilizations and atomic level quadrupole coupling constant (CQ) properties have been investigated for graphene–like monolayers (G–monolayers) of boron nitride (BN), boron phosphide (BP), aluminum nitride (AlN), and aluminum phosphide (AlP) structures. To this aim, density functional theory (DFT) calculations have been performed to optimize the model structures and also to evaluate the CQ parameters. The results of optimizations indicated that the formations, polarities, and semiconducting properties of BN G–monolayer are more favorable than other investigated G–monolayers. Moreover, the atomic level CQ parameters also indicated that the atoms at the tips of monolayers have the most activities among other atoms and different properties have been seen for the atoms at different positions of monolayers. Differences of electronegativities are also important for the magnitudes of CQ properties as could be seen by larger values of CQ parameters for B and Al atoms in the BN and AlN G–monolayers in comparison with BP and AlP G–monolayers.
- انتشار مقاله: 21-10-1394
- نویسندگان: Mahmoud Mirzaei,Rahman Salamat Ahangari
- مشاهده
- جایگاه : پژوهشی
- مجله: Asian Journal of Green Chemistry
- نوع مقاله: Journal Article
- کلمات کلیدی: Molecular docking,propylthiouracil,Tautomer,Lactoperoxidase,quantum computation
- چکیده:
- چکیده انگلیسی: Lactoperoxidase (LPO) enzyme inhibition by tautomeric propylthiouracil (PTU) structures have been investigated in this work based on the in silico methodologies. Six possible PTU structures have been optimized to obtain their energy-minimized structures based on quantum mechanics computations. Afterwards, their interactions with LPO enzyme have been evaluated based on molecular docking simulations. The results indicated that the structural changes of PTU analogues could perturbate the interaction properties, in which it could be seen by either the magnitudes of binding energies or the types of interacting amino acids. In this work, the original thio-keto structure of PTU showed better interaction properties with LPO enzyme; however, the properties for other PTU derivatives have been deviated from this reference model. It is known that the tautomerism is common for biological structures; therefore, exploring their arisen effects on the structural properties and activities could reveal insightful information for judging their potency and efficacy.
- انتشار مقاله: 25-10-1397
- نویسندگان: Mehdi Soleimani,Mahmoud Mirzaei,Mohammad R. Mofid,Ghadamali Khodarahmi,S. Farid Rahimpour
- مشاهده