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81.
CuO–CeO2 is reported as a highly efficient and green recyclable catalyst,for the multicomponent synthesis of 4H-benzo[b]pyran derivatives.The catalyst was synthesized by a co-precipitation method and characterized by XRD,BET specific surface area,ESEM and EDS analysis.This synthetic method provides several advantages such as simple work-up procedures,minimal amount of waste generated,short reaction time,and high yields of products. 相似文献
82.
Muhammad Sagir Isa M. Tan Muhammad Mushtaq Lukman Ismail Muhammad Nadeem Muhammad Rizwan Azam 《Journal of Dispersion Science and Technology》2014,35(3):463-470
The synthesis of novel CO2 philic surfactant using maleic anhydride and dipropylene tertiary butyl alcohol is reported. The synthesis involved the esterification of maleic anhydride to produce bis(2-(2-(tert-butoxy)propoxy)propyl) maleate and subsequent sulfonation of the esterified product. Para toluene sulfonic acid was employed as catalyst for the esterification reaction. The esterification reaction was optimized for the maximum yield of 98% of bis(2-(2-(tert-butoxy)propoxy)propyl) maleate. The esterification reaction kinetics employing heterogeneous catalyst were also studied. Although this is a bimolecular reaction, a first order reaction kinetics with respect to acid has been observed. The activation energy was found to be 58.71 kJ/mol. The diester was followed by the sulfonation process and a yield of 85% of surfactant was achieved. The synthesized surfactant successfully lowered down the IFT between CO2/brine to 1.93 mN/m. This surfactant has a great potential to be used for CO2-EOR applications. 相似文献
83.
Askari Azam Entezari Amir Arsalan Pordel Mehdi Beigoli Sima Nezafat Yazdi Zeinab Jahani Moghaddam Arya Chamani Jamshidkhan 《Journal of the Iranian Chemical Society》2020,17(1):135-149
Journal of the Iranian Chemical Society - Evaluating the binding interaction between biomacromolecules and various chemical compounds is one of the most biologically researched topics. The present... 相似文献
84.
Masoud Salavati-Niasari Azam Sobhani Sanaz khoshrooz Noshin Mirzanasiri 《Journal of Cluster Science》2014,25(4):937-947
PbS nanoparticles have been successfully synthesized through a simple, rapid microwave route using lead (II) oxalate as precursor, [Pb(O4C2)]. In this study, four different sulfur sources were applied that including sodium thiosulfate (Na2S2O3), thioacetamide (NH2CSCH3), thioglycolic acid (HSCH2CO2H), and l-cysteine (HO2CCH(NH2)CH2SH). The effects of sulfur sources on morphology and size of products in two different solvents, ethylene glycol (EG) and poly EG (PEG 400), were investigated. The products were analyzed by X-ray diffraction analysis, scanning electron microscopy, Fourier transform infrared spectroscopy and X-ray energy dispersive spectroscopy. Photoluminescence was used to study the optical properties of PbS nanoparticles. 相似文献
85.
Behrooz Maleki Saba Hemmati Reza Tayebee Sirous Salemi Yasaman Farokhzad Mehdi Baghayeri Farrokhzad Mohammadi Zonoz Elahe Akbarzadeh Rohollah Moradi Azam Entezari Mohammad Reza Abdi Samaneh Sedigh Ashrafi Fereshteh Taimazi Majid Hashemi 《Helvetica chimica acta》2013,96(11):2147-2151
A convenient synthesis of sulfonamides and sulfonyl azides from thiols is described. In situ preparation of sulfonyl chlorides from thiols was accomplished by oxidation with chloramine‐T (=N‐chlorotosylamide=N‐chloro‐4‐methylbenzenesulfonamide), tetrabutylammonium chloride (Bu4NCl), and H2O. The sulfonyl chlorides were then further allowed to react with excess amine or NaN3 in the same pot. 相似文献
86.
Nima Taghavinia Azam Iraji-zad S. Mohammad Mahdavi M. Reza-esmaili 《Physica E: Low-dimensional Systems and Nanostructures》2005,30(1-2):114-119
A photochemical approach on the size control of CdS nanoparticles is presented. CdS nanoparticles were grown using the photo-induced reaction of sodium thiosulfate with Cadmium sulfate, in the absence of any surfactant. Particles of 5.5–11 nm were obtained by changing the illumination time. The dark growth of nanoparticles was negligible, however we found by optical scattering measurements that a ripening phenomenon occurs and the size of nanoparticles slightly increases with time. 相似文献
87.
Some novel ferrocenyl linked pyrazoline analogs were synthesized, well characterized, and evaluated for in vitro antiamoebic activity against HM1 : IMSS strain of Entamoeba histolytica. Most of the compounds exhibited higher antiamoebic activity with the IC50 value in the range of 0.12–1.20 μM, than the reference drug metronidazole, (IC50 value of 1.78 μM). Compound 9 showed the most promising antiamoebic activity (IC50 = 0.12 μM), concluding that these compounds hold immense potential to be employed as new antiamoebic agents. Also, being novel, they can be a solution to the increasing resistance that has posed a major problem globally. 相似文献
88.
Application of a new nanoporous sorbent for extraction and pre-concentration of lead and copper ions
Vahid Zarezade Azam Aliakbari Moosa Es’haghi Mostafa M. Amini Fariborz Omidi 《International journal of environmental analytical chemistry》2017,97(4):383-397
The authors describe a method for the trace determination of copper (II) and lead (II) in water and fish samples using solid-phase extraction via siliceous mesocellular foam functionalised by dithizone. Siliceous mesocellular was functionalised with dithizone, and the resulting sorbent was characterised by scanning electron microscopy, surface area analysis, thermogravimetric/differential thermal analysis and FTIR. Following solid-phase extraction of target ions by the sorbent, copper and lead ions were quantified by flame atomic absorption spectrometry. Factors affecting the sorption and desorption of target ions by the sorbent were evaluated and optimised. The calibration plot is linear in the 1 – 500 μg L?1 copper (II) and 3–700 μg L?1 lead (II) concentration range. The relative recovery efficiency in real sample analysis is in the range from 96 to 102%, and precision varies between 1.7 and 2.8%. It is should be noted that the limits of detection for the copper and lead analysis were 0.8 and 1.6 μg L?1, respectively. Also, the adsorption capacities for copper and lead ions were 120 and 160 mg g?1, respectively. The obtained pre-concentration factor for the lead and copper ions by the proposed solid-phase extraction was 75. The method was successfully applied to the determination of low levels of copper (II) and lead (II) in tap, Caspian sea, Persian gulf and lake water and also their detection in fish samples. 相似文献
89.
DNA gyrase subunit B (GyrB) is an attractive drug target for the development of antibacterial agents with therapeutic potential. In the present study, computational studies based on pharmacophore modelling, atom-based QSAR, molecular docking, free binding energy calculation and dynamics simulation were performed on a series of pyridine-3-carboxamide-6-yl-urea derivatives. A pharmacophore model using 49 molecules revealed structural and chemical features necessary for these molecules to inhibit GyrB. The best fitted model AADDR.13 was generated with a coefficient of determination (r²) of 0.918. This model was validated using test set molecules and had a good r² of 0.78. 3D contour maps generated by the 3D atom-based QSAR revealed the key structural features responsible for the GyrB inhibitory activity. Extra precision molecular docking showed hydrogen bond interactions with key amino acid residues of ATP-binding pocket, important for inhibitor binding. Further, binding free energy was calculated by the MM-GBSA rescoring approach to validate the binding affinity. A 10 ns MD simulation of inhibitor #47 showed the stability of the predicted binding conformations. We identified 10 virtual hits by in silico high-throughput screening. A few new molecules were also designed as potent GyrB inhibitors. The information obtained from these methodologies may be helpful to design novel inhibitors of GyrB. 相似文献
90.
Farrusseng D Clerc F Mirodatos C Azam N Gilardoni F Thybaut JW Balasubramaniam P Marin GB 《Combinatorial chemistry & high throughput screening》2007,10(2):85-97
We discuss thoroughly aspects and issues for the development of a bespoke, but generic, electronic infrastructure designed to cope with the dynamic in high-throughput experimentation and knowledge management, is applicable to large or contract research organizations. We present the first generation of an informatics platform developed for TOPCOMBI, a research project funded by the European Commission for Nanotechnology and Nanoscience. It is composed by an infrastructure and a collection of modules dealing with laboratory analytics, robotics, data handling and analytics, optimization, in-database processing and visualization, which are developed collegially by the partners of the Consortium. This best-of-breed informatics system enables the capture and the re-usage of processes and methodologies, i.e. process and data flows, using the workflow paradigm. Complex workflows designed by power users can be eventually used by either other domain experts or by novices through a web portal. Workflows can also be run interactively to allow visual analytics for instance, or automatically. We present two case studies dealing with the kinetic study of glycerol catalytic oxidation using parallel equipments, and a novel, fully integrated QSAR applied in heterogeneous catalysis, respectively. 相似文献