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21.
Mohammad Hossein Keshavarz Somayeh Moradi Bahman Ebrahimi Saatluo Hadi Rahimi Ali Reza Madram 《Journal of Thermal Analysis and Calorimetry》2013,112(3):1453-1463
A novel general method is introduced to predict deflagration temperature of organic energetic compounds containing at least –NNO2, –ONO2, or –CNO2 groups. Deflagration temperature is an important safety parameter in working with dangerous energetic compounds and their environmental problems. It is shown that the contribution of some molecular structure parameters can be used to interpret thermal decomposition of an energetic compound. For 86 energetic materials (corresponding to 102 measured values) with different molecular structures, the new correlation has the root mean square (rms) and the average deviations of 23.8 and 19.0 K, respectively. The new method is also tested for some energetic compounds with complex molecular structures, e.g., two new organic energetic molecules N,N′-bis(1,2,4-triazol-3yl)-4,4′-diamino-2,2′,3,3′,5,5′,6,6′-octanitroazobenzene (BTDAONAB) and 2,4,6-trinitrophloroglucinol. 相似文献
22.
Ali Khalafi-Nezhad Farhad Panahi Somayeh Mohammadi Habib Ollah Foroughi 《Journal of the Iranian Chemical Society》2013,10(2):189-200
Silica boron–sulfuric acid nanoparticles (SBSANs) as a solid Lewis-protic acid have been found to be an efficient heterogeneous catalyst in the synthesis of xanthene and acridine derivatives. The SBSAN-catalyzed reaction between carbonyl compound (aldehyde/ketone/ethyl orthoformate) and 5,5-dimethyl-1,3-cyclohexanedione (dimedone) for synthesis of xanthene derivatives is performed under mild conditions with the excellent isolated yield. Also, we can apply a broad scope of carbonyl compounds and amines for efficient synthesis of various acridine derivatives in the presence of SBSAN catalyst. In these multicomponent approaches the SBSAN catalyst can be reused for several times without any treatment in its catalytic activity. 相似文献
23.
In present work, the ionic liquid, 1‐butyl‐3‐methylimidazolium bis (trifluoromethylsulfonyl) imide was incorporated in the carbon paste electrode as the binder (IL‐CPE). O‐anisidine (OA) monomer is electropolymerized in the presence of an aqueous acidic solution onto IL‐CPE (POA/IL‐CPE). The as‐prepared substrate is used as a porous matrix for dispersion of Ni(II) ions by immersing the modified electrode in a nickel(II) nitrite solution. The modified electrodes are characterized by scanning electron microscopy (SEM) and electrochemical methods. The POA/IL‐CPE was applied successfully to highly efficient (current density of 18.2 mA cm?2) electrocatalytic oxidation of formaldehyde in alkaline medium. Finally, the rate constant for chemical reaction between formaldehyde and redox sites of the electrode was calculated. 相似文献
24.
Mohammad Navid Soltani Rad Somayeh Behrouz Abdollah Movahedian Mohammad Mahdi Doroodmand Younes Ghasemi Sara Rasoul‐Amini Abdol‐Rasoul Ahmadi Gandomani Ramin Rezaie 《Helvetica chimica acta》2013,96(4):688-701
A facile and simple protocol for the 1,3‐dipolar cycloaddition of organic azides with terminal alkynes catalyzed by doped nano‐sized Cu2O on melamine? formaldehyde resin (nano‐Cu2O? MFR) as a new and convenient heterogeneous catalyst is described. In this method, ‘click’ cycloaddition of various structurally diverse β‐azido alcohols and alkynes in the presence of nano‐Cu2O? MFR in H2O/THF 1 : 2 furnished the corresponding 1,4‐disubstituted 1H‐1,2,3‐triazole adducts 1a – 1o in good to excellent yields at room temperature (Scheme and Table 3). The nano‐Cu2O? MFR was characterized by scanning electron microscopy (SEM), X‐ray diffraction (XRD), inductively coupled plasma (ICP) analysis, and FT‐IR. The nano‐Cu2O? MFR could be easily recovered and recycled from the reaction mixture and reused for many consecutive trials without significant decrease in activity (Table 4). The in vitro antibacterial activities of all synthesized compounds were tested on several Gram‐positive and/or Gram‐negative bacteria (Table 5). The results demonstrate the promising antibacterial activity for some of the synthesized compounds. 相似文献
25.
A facile and efficient method for dehydration of aldoximes into nitriles using N-(p-toluenesulfonyl) imidazole (TsIm) is described. In this method, aldoximes were refluxed with TsIm in the presence of 1,8-diazabicyclo-[5.4.0]undec-7-ene (DBU) in dimethylformamide (DMF) to afford the corresponding nitriles in good yields. This methodology is highly efficient for various structurally diverse aldoximes including aromatic, heteroaromatic, and aliphatic oximes. A plausible mechanism for the conversion of aldoxime into nitriles using TsIm/DBU is explained. 相似文献
26.
Colloidal gas aphrons (CGAs) are gas bubbles with diameters ranging from 10 to 100 microns, generated by intense stirring of a surfactant solution at high speed. The surface activity and aggregation behavior of the surfactant affects the size/size distribution, stability, and other physicochemical properties of generated aphrons. Therefore, selection of a suitable surfactant is important for the generation of microbubbles with the desired properties. The goal of this articleis to investigate the potential use of a new plant-derived surfactant as an aphronizer surfactant in preparation of CGA-based drilling fluids for accomplishing desirable rheological and filtration properties. For this purpose, natural surfactant obtained from leaves of special tree, namely, Zizyphusspina Christi and used for preparation of aphron-based fluids. To achieve the research objectives, laboratory tests of suspension generation, microscopic visualization, initial yield, filtration loss, and rheological characterization with varying concentrations of surfactant and polymer were performed. Experimental results demonstrate that newly proposed biosurfactant has a great potential for application in preparation of CGA-based drilling fluids for implementation in petroleum drilling industry. 相似文献
27.
Marzieh Mohammadi Akram Zamani Keikhosro Karimi 《Applied biochemistry and biotechnology》2013,171(6):1465-1472
In this study, the effect of phosphorous compound concentration on the production of glucosamine by Mucor indicus was investigated. Changes in the yield of ethanol, the major metabolite of the fungus, were also followed besides. The alkali insoluble material of the biomass of the fungus mainly contained phosphates and polymers of glucosamine and N-acetyl glucosamine, i.e., chitin and chitosan. Yields of glucosamine (78–113 g/kg dry fungal biomass) and ethanol (200–370 g/kg glucose) were significantly affected by the phosphorous concentration. The results showed that lower concentrations of phosphorous favored the production of glucosamine while higher ethanol as well as biomass yields was obtained at higher concentrations. The best concentration was 0.5 g/l where glucosamine yield was 0.37 g/l (11 % of the biomass). At this phosphate concentration, ethanol and biomass yields were 360 and 76 g/kg glucose, respectively. On average, proteins comprised 51.5 % of the biomass. Glycerol was the second important metabolite during the fermentation by the fungus which appeared at lower yields (20–34 g/kg glucose). 相似文献
28.
Hossein Faghihian Alimohammad Hajishabani Shayesteh Dadfarnia Hassan Zamani 《International journal of environmental analytical chemistry》2013,93(4):223-231
A solid phase extraction system for separation and preconcentration of trace amounts of Pb(II), Ni(II), Cd(II) and Cu(II) is proposed. The procedure is based on the adsorption of Pb2+, Ni2+, Cd2+ and Cu2+ ions on a column of 1-(2-pyridylazo)-2-naphthol (PAN) immobilised on surfactant-coated clinoptilolite prior to their determinations by Flame Atomic Absorption Spectroscopy (FAAS). The effective parameters including pH, sample volume, sample flow rate and eluent flow rate were also studied. The analytes collected on the column were eluted with 5 mL of 1 mol L?1 nitric acid. A concentration factor of 180 can be achieved by passing 900 mL of sample through the column. The detection limits (3 s) for Cd, Cu, Pb and Ni were found to be 0.28, 0.12, 0.44 and 0.46 µg L?1, respectively. The relative SDs at 10 µg L?1 (n = 10) for analytes were in the range of 1.2–1.4%. The method was applied to the determination of Pb, Ni, Cd and Cu in water samples. 相似文献
29.
Farhad Shirini Masoumeh Abedini Somayeh Akbari-Dadamahaleh Arman Rahmaninia 《Journal of the Iranian Chemical Society》2014,11(3):791-824
Xanthenes and their derivatives as very important classes of organic compounds are key structural elements of many biologically active compounds. These materials are important heterocyclic nucleus of various dyes and drugs. Because of their wide range of pharmacological, industrial and synthetic applications, many methods for the preparation of xanthenes are reported in the literature. In recent years, among the other chemists, introduction of new methods for the preparation of these types of compounds has attracted the attention of Iranian chemists. The result of these efforts is the introduction of appropriate, effective and efficient methods. In this paper, we have a brief review on these methods and their main advantages and important applicabilities. 相似文献
30.
Sajedi Mohammad Mansoori Yagoub Nuri Ayat Fekri Somayeh Esquivel Dolores Navarro M Angeles 《Catalysis Surveys from Asia》2022,26(3):193-210
Catalysis Surveys from Asia - 2-(2-Pyridyl)benzimidazole (PyBzIm) was supported onto magnetic mesoporous silica, Fe3O4@SiO2@SBA-15 via the click chemistry. The supported ligand was treated with... 相似文献