排序方式: 共有239条查询结果,搜索用时 31 毫秒
161.
Sepahvand M. Fazaeli R. Jameh-Bozorghi S. Niazi A. 《Russian Journal of Applied Chemistry》2019,92(1):141-149
Russian Journal of Applied Chemistry - In the present investigation, we synthesized copper (I) oxide nanoparticles (NPs) by the coprecipitation method. The obtained materials were characterized by... 相似文献
162.
Seyed Abolfazl Hosseini‐Yazdi Ali Akbar Khandar Hashem Azizi Amir Reza Aref 《无机化学与普通化学杂志》2008,634(11):1943-1949
The 18‐membered mixed‐donor macrocycle 6,7,8,9,10,11,12,13,20,21‐decahydro‐5H, 19H‐dibenzo[b,m][1,15,5,8,11]dioxatriazacyclooctadecin‐20‐ol ( L ), which contains N3O3 donor set, was synthesized. Also two nickel(II) complexes of L have been synthesized and characterized by X‐ray crystallography, FT‐IR, UV‐Vis absorption spectroscopy and elemental analysis. The structure of complexes shows an unexpected anion dependence. Reaction of Ni(ClO4)2·6H2O with L afforded [Ni L ](ClO4)2·CH2Cl2 complex in which L uses all donor atoms and acts as a hexadentate ligand so forming a mononuclear nickel(II) complex in distorted octahedral geometry. Contrasting with this, when NiCl2·6H20 is used, the product complex [{Ni L Cl}2(μ‐Cl)2] is dimeric and consists of two Ni L Cl units bridged by two chloride ions. The coordination geometry of each nickel atom is a distorted octahedral. In this complex L is exo‐coordinated via only three nitrogen atoms to a nickel ion, which is bound to two cis bridging chloride and one non‐bridging chloride too. Also complexing properties of L towards Ni(ClO4)2·6H2O and NiCl2·6H20 have been determined by UV‐Vis titration in methanol. The computer treatment of the data confirmed the 1:1 metal to ligand stoichiometry for two complexes in solution and gave reliable values for corresponding stability constants (logK = 3.00 ± 0.02 with Ni(ClO4)2·6H2O and logK = 3.29 ± 0.06 with NiCl2·6H20). 相似文献
163.
Javad Safaei-Ghomi Hossein Shahbazi-Alavi Abolfazl Ziarati Raheleh Teymuri Mohammad Reza Saberi 《中国化学快报》2014,25(3):401-405
CuI nanoparticles as an efficient catalyst have been used for the preparation of 1H-pyrazolo[1,2-b]phthalazine-5,10-diones by the four-component condensation reaction of phthalic anhydride, hydrazine monohydrate, aromatic aldehydes and malononitrile or ethyl cyanoacetate under solventfree conditions in good to excellent yields, short reaction times and environmentally benign, milder reaction conditions. 相似文献
164.
Narges Zohari Mohammad Hossein Keshavarz Seyed Abolfazl Seyedsadjadi 《Journal of Thermal Analysis and Calorimetry》2014,117(1):423-432
A new relationship is introduced between impact sensitivity of energetic compounds and their activation energies of thermal decomposition. In this relationship, the impact sensitivity of an energetic compound with general formula CaHbNcOd is a function of its activation energy of thermal decomposition as well as the ratio of \( \left( {\frac{{n_{\text{H}} }}{{n_{\text{O}} }}} \right) \) and the contribution of specific molecular structural parameters. The new correlation can help us to elucidate the mechanism of initiation of energetic materials by impact. It can be used to predict the magnitude of impact sensitivity of new energetic materials. The new correlation has the root mean square and the average deviations of 2.22 and 1.79 J, respectively, for 40 energetic compounds with different molecular structures. The proposed new method is also tested for 11 energetic compounds, which have complex molecular structures, e.g., 4,10-dinitro-2,6,8,12-tetraoxa-4,10-diazaisowurtzitane and 1,3,7,9-tetranitrophenoxazine. 相似文献
165.
Omid Taheri Mahdi Behzad Abolfazl Ghaffari Maciej Kubicki Grzegorz Dutkiewicz Abolfazl Bezaatpour Hossein Nazari Ali Khaleghian Abolfazl Mohammadi Mehdi Salehi 《Transition Metal Chemistry》2014,39(2):253-259
A series of new derivatives and previously reported Schiff base ligands and their oxidovanadium(IV) complexes were synthesized, characterized and tested as potential antibacterial agents against four human pathogenic bacteria. These N2O2 type Schiff base ligands were derived from the condensation of meso-1,2-diphenyl-1,2-ethylenediamine with different salicylaldehyde derivatives, and their metal complexes were obtained from the reaction of these ligands with bis(acetylacetonato)oxidovanadium(IV). Our studies showed that the metal complexes had moderate antibacterial activity, and this activity was higher than that of the free ligands against both Gram-positive and Gram-negative bacteria. Besides, it was found that the presence of more substituents on the ligands increases the antibacterial activities of both the free ligands and their complexes. The crystal structures of H2L4 and its corresponding complex VOL4 were determined by X-ray crystallography. 相似文献
166.
Hedayat Haddadi Mahboube Shirani Abolfazl Semnani Mohammad Rezaee Hossein Ali Mashayekhi Akram Hosseinian 《Chromatographia》2014,77(9-10):715-721
A new method was developed for the simultaneous determination of deltamethrin and permethrin in water samples with homogeneous liquid–liquid microextraction via flotation assistance and gas chromatography–flame ionization detection. A special extraction cell was designed to facilitate collection of the low density solvent extracts. The sample solution was added into the extraction cell, which contained an appropriate mixture of n-hexane (as an extraction solvent) and acetone (as a homogeneous solvent). Air flotation allowed the extraction solvent to be collected from the top of the solution. Under the optimum conditions, good linearity was observed in the range of 1.0–200 μg L?1 with a correlation coefficient (r 2) greater than 0.9980 for both of the analytes. The limits of detection were 0.2 and 0.3 μg L?1 for deltamethrin and permethrin, respectively (S/N = 3). The developed method was successfully applied to determine the two pesticides in three different water samples. 相似文献
167.
Safaei-Ghomi Javad Shahbazi-Alavi Hossein Sadeghzadeh Reyhaneh Ziarati Abolfazl 《Research on Chemical Intermediates》2016,42(12):8143-8156
Research on Chemical Intermediates - A simple and efficient method for the preparation of pyrazolopyridines by a multicomponent reaction of ethyl acetoacetate, an aldehyde, hydrazine and ammonium... 相似文献
168.
169.
Razieh Fazaeli Hamid Aliyan Mohammad Javad Bagi 《Phosphorus, sulfur, and silicon and the related elements》2013,188(6):677-688
Abstract We have used SBA-15 silicas as hard templates for the nano-fabrication of Cs1.8H2.2SiW12O40 (CsHSiW) salt nanocrystal. The elimination by HF (or NaOH 90 °C) in the silica matrix from the composites occurred by a two-step reaction deposition of CsHSiW salt nanocrystal. The nano-casted CsHPW materials were characterized by several techniques: chemical analysis (atomic absorption, neutron activation analysis, and inductively coupled plasma) and spectroscopic methods (FT-IR spectrum, X-ray diffraction, transmission electron microscopy, and energy dispersive x-ray analysis measurement). In addition to the complete characterization of CsHSiW nanocrystal samples, their catalytic performances are shown for the three-component Hosomi–Sakurai reaction. The reaction proceeds efficiently under ambient conditions with good to excellent yields. Supplemental materials are available for this article. Go to the publisher's online edition of Phosphorus, Sulfur, and Silicon and the Related Elements to view the free supplemental file. 相似文献
170.
Mojtaba Koosha Nastaran Ebrahimi Yousef Jahani Seyed Abolfazl Seyed Sajjadi 《Radiation Physics and Chemistry》2011,80(7):810-816
This study considers the effects of electron beam radiation on degradation kinetics of a poly(propylene-co-ethylene) heterophasic copolymer. Polypropylene heterophasic copolymers are composed of ethylene–propylene rubbery phase dispersed in crystalline polypropylene homopolymer matrix. Electron beam radiation can affect both polypropylene homopolymer matrix and ethylene–propylene dispersed phases simultaneously. Both phases undergo degradation and crosslinking reactions, but degradation is more probable in the polypropylene homopolymer matrix. The aim of this work is to study kinetics of degradation in this material. A high power electron accelerator irradiated raw samples under nitrogen atmosphere. The samples are analyzed using TGA in non-isothermal mode, and the degradation kinetic parameters were determined using Kissinger, Flynn–Wall–Ozawa and Coats–Redfern methods. The kinetic parameters resulted from these methods are compared. Results of kinetics studies show that orders of degradation reactions occurring in nitrogen atmosphere are all less than one. It indicates degradation takes place due to thermal dissociation of the chemical bonds. 相似文献