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401.
Mahdi Mirzaee Tayebeh Tamizkar Gholamhossein Mohammadnezhad Hamid Reza Khavasi Mostafa M. Amini 《Comptes Rendus Chimie》2011,14(10):927-933
Stochiometric reaction of salicylaldoxime and tantalum or niobium ethoxide in toluene at room temperature resulted in formation of [M2O(C7H5NO2)2(C2H5O)4], M=Ta and Nb which were crystallized from CH2Cl2 at −5 °C and characterized by spectroscopic techniques. The molecular structures of [Ta2O(C7H5NO2)2(C2H5O)4] was determined by single-crystal X-ray diffraction and compared with molecular structure of [Nb2O(C7H5NO2)2(C2H5O)4]. The geometries at metal atoms are distorted octahedron which shared an apex through bridged oxygen. Each dianionic salicylaldoximate ligand chelates to the one metal ion through its phenolic oxygen and oximate nitrogen atoms, and to another metal ion through its oximate oxygen atom. 相似文献
402.
Navid Amini Saeedeh Mazinani Seyed-Omid Ranaei-Siadat Mohammad Reza Kalaee Saeed Hormozi Kaveh Niknam Nasrin Firouzian 《Applied biochemistry and biotechnology》2013,170(1):91-104
In this work, polyacrylamide/multi-walled carbon nanotubes (MWCNT) solution is electrospun to nanocomposite nanofibrous membranes for acetylcholinesterase enzyme immobilization. A new method for enzyme immobilization is proposed, and the results of analysis show successful covalent bonding of enzymes on electrospun membrane surface besides their non-covalent entrapment. Fourier transform infrared spectroscopy, mechanical and thermal investigations of nanofibrous membrane approve successful cross-linking and enzyme immobilization. The enzyme relative activity and kinetic on both pure and nanocomposite membranes is investigated, and the results show proper performance of designed membrane to even improve the enzyme activity followed by immobilization compared to free enzyme. Scanning electron microscopy images show nanofibrous web of 3D structure with a low shrinkage and hydrogel structure followed by enzyme immobilization and cross-linking. Moreover, the important role of functionalized carbon nanotubes on final nanofibrous membrane functionality as a media for enzyme immobilization is investigated. The results show that MWCNT could act effectively for enzyme immobilization improvement via both physical (enhanced fibers’ morphology and conductivity) and chemical (enzyme entrapment) methods. Figure
Mechanism for APTS surface modification of nanofibrous nanoweb for enzyme immobilization 相似文献
403.
Ali Saffar-Teluri Shiva Bolouk Mohammad Hossein Amini 《Research on Chemical Intermediates》2013,39(7):3345-3353
Flower and broken sheet-like zinc oxide (ZnO) microcrystals have been prepared via a thermal decomposition process, using Zn5(CO3)2(OH)6 as the precursor in the presence of glycerol at 300 and 600 °C. The ZnO products were examined as a photocatalyst for the UV-induced degradation of Yellow 181 and Red 245 (textile azo dyes) in water solution. The applicability of the Langmuir–Hinshelwood kinetic equation revealed that the degradation of dyes occurred mainly on the surface of the photocatalyst. 相似文献
404.
Reza Ghiasi Elaheh Amini 《Russian Journal of Physical Chemistry A, Focus on Chemistry》2013,87(10):1684-1691
The electronic structure and properties of the iridathiabenzene and iridaoxabenzene isomers have been investigated using the hybrid density functional mpw1pw91 theory. The energetic aspect shows that trans-ortho-isomer is the most stable isomer. This is compatible with principles of minimum energy and minimum polarizability. Molecular orbital analysis shows a linear correlation between hardness and anisotropic polarizability values for Iridathiabenzene and iridaoxabenzene isomers. The structural and natural bond analysis (NBO) results illustrate electronic delocalization in these rings. Also, the study of non linear optical properties of these molecules indicate a good correlation between βtot and E(HOMO) for iridathiabenzene. The results from natural bond orbital (NBO) analysis have provided insights into Ir—ligand, P—Hapical and P—Hbasal bonding. 相似文献
405.
Yousef Fazaeli Amir R. Jalilian Mostafa M. Amini Ali Rahiminejad-kisomi Saeed Rajabifar Fatemeh Bolourinovin Sedigheh Moradkhani 《Journal of Radioanalytical and Nuclear Chemistry》2011,288(1):17-24
[67Ga]labeled tetraphenyl porphyrin ([67Ga]-TPP) was prepared using freshly prepared [67Ga]GaCl3 and tetraphenyl porphyrin (TPPH2) for 30–60 min at 25 °C (radiochemical purity: >97 ± 1% ITLC, >98 ± 0.5% HPLC, specific activity: 13–14 GBq/mmol). Stability
of the complex was checked in final formulation and human serum for 24 h. The partition coefficient was calculated for the
compound (log P 1.89). The biodistribution of the labeled compound in vital organs of wild-type rats was studied using scarification studies
and SPECT imaging up to 24 h. A detailed comparative pharmacokinetic study performed for 67Ga cation and [67Ga]-TPP. The complex is mostly washed out from the circulation through kidneys and can be an interesting tumor imaging/targeting
agent due to low liver uptake and rapid excretion through the urinary tract. 相似文献
406.
Homeira Ebrahimzadeh Najmeh Tavassoli Omid Sadeghi Mostafa M. Amini Moein Jamali 《Mikrochimica acta》2011,172(3-4):479-487
A technique for solid-phase extraction utilizing pyridine-functionalized nanoporous silica (MCM-41, MCM-48 and SBA-15) was developed for the determination of gold in different samples using flame atomic absorption spectrometry. The effects of concentration and volume of eluent, pH of the solution, flow rate of extraction, sample volume and of potentially interfering ions on the efficiency of preconcentration and recovery was investigated. The limit of detection is lower than 45 pg mL?1. Under optimal conditions, the accuracy and precision (RSD%) of the method were calculated to be >99.5% and <0.7% for the two MCMs (41 and 48) and >89.5%, and <1.5% for SBA-15, respectively. The SPE technique was used to determine the concentration of gold in natural and industrial wastewater with satisfactory results. Figure
A schematic model of modified mesoporous (MCM-41, MCM-48, SBA-15) with pyridine, and adsorption of Au(III) 相似文献
407.
Bagher Eftekhari-Sis Zahra Rezazadeh Ali Akbari Mojtaba Amini 《Journal of fluorescence》2018,28(5):1173-1180
A nanosensor, based on 8-hydroxyquinoline functionalized graphene oxide, was developed for the fluorescence detection of Zn2+. It showed high selectivity and sensitivity for Zn2+ion in aqueous solution over other metal ions such as Li+, Na+, Ca2+, Mg2+, Al3+, Cd2+, Co2+, Cu2+, Hg2+, Ni2+, Pb2+, Fe2+, Fe3+and Cr3+. Due to the linearity of the emission intensity toward Zn2+ concentration, fluorescent technique could be used for the detection of Zn2+ ion even at very low concentrations. 相似文献
408.
Tayyeb Ghadimi Soheila Naderi Gharahgheshlagh Noorahmad Latifi Ahmad Hivechi Vahid Hosseinpour Sarmadi Siamak Farokh Forghani Naser Amini Peiman B. Milan Fatemeh Latifi Masoud Hamidi Ghazaleh Larijani Seyed Mohammad Amin Haramshahi Motahareh Abdollahi Fatemeh Ghadimi Saeed Nezari 《Macromolecular bioscience》2023,23(9):2300033
Burn is one of the physically debilitating injuries that can be potentially fatal; therefore, providing appropriate coverage in order to reduce possible mortality risk and accelerate wound healing is mandatory. In this study, collagen/exo-polysaccharide (Col/EPS 1–3%) scaffolds are synthesized from rainbow trout (Oncorhynchus mykiss) skins incorporated with Rhodotorula mucilaginosa sp. GUMS16, respectively, for promoting Grade 3 burn wound healing. Physicochemical characterizations and, consequently, biological properties of the Col/EPS scaffolds are tested. The results show that the presence of EPS does not affect the minimum porosity dimensions, while raising the EPS amount significantly reduces the maximum porosity dimensions. Thermogravimetric analysis (TGA), FTIR, and tensile property results confirm the successful incorporation of the EPS into Col scaffolds. Furthermore,the biological results show that the increasing EPS does not affect Col biodegradability and cell viability, and the use of Col/EPS 1% on rat models displays a faster healing rate. Finally, histopathological examination reveals that the Col/EPS 1% treatment accelerates wound healing, through greater re-epithelialization and dermal remodeling, more abundant fibroblast cells and Col accumulation. These findings suggest that Col/EPS 1% promotes dermal wound healing via antioxidant and anti-inflammatory activities, which can be a potential medical process in the treatment of burn wounds. 相似文献