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91.
Sania Saheli Ali Reza Rezvani Azadeh Arabshahi Michal Dusek Erika Samolova Marketa Jarosova 《应用有机金属化学》2021,35(1)
In order to increase the catalyst activity for Fischer–Tropsch synthesis (FTS), the preparation methods of two new catalysts were studied. The chemically identical bimetallic Co–Mn/Al2O3 catalysts were synthesized by different synthetic methods: (a) via thermal decomposition of the complex [Co1.33Mn0.667(C7H3NO4)2(H2O)5].2H2O ( 1 ) and (b) by the impregnation technique. The complex was characterized by the single‐crystal analysis, elemental analysis, and Fourier‐transform infrared (FT‐IR) spectroscopy. Both catalysts were characterized by powder X‐ray diffraction (XRD), scanning electron microscopy (SEM), energy dispersive X‐ray spectrometry (EDS), Brunauer–Emmett–Teller (BET) specific surface area, hydrogen temperature‐programmed reduction (H2‐TPR), and H2‐chemisorption. The catalysts' activity was investigated for the Fischer–Tropsch synthesis in a fixed bed microreactor. Higher activity was obtained for the catalyst prepared by thermal decomposition of the inorganic precursor due to its small particle size, superior dispersion, and higher surface area. The results show that the catalyst prepared thermal decomposition has 21% ethylene, 10% propylene, and 50% C5+ selectivity, while methane selectivity of this catalyst is 11% at 250°C. On the other hand, the catalyst obtained by the impregnation method displays 15% ethylene, 8% propylene, 29% C5+, and 29% methane selectivity at the same temperature. 相似文献
92.
A PVC-based sensor for La3+ ions based on N-[hexahydrocyclopentapyrol-2((1H)yl)amino]carbonyl]-4-methyl benzene sulfonamide (gliclazide) as a novel carrier was prepared. The electrode exhibits a Nernstian response for La3+ over a wide concentration range (1.0×10−1-1.0×10−6 M) with a slope of 20.1 mV per decade. The limit of detection is 8.0×10−7 M. The sensor has a very short response time (<15 s) and a useful working pH range of 4.0-8.0. The proposed membrane sensor shows excellent discriminating ability towards La3+ ions with regard to several alkali, alkaline earth, transition and heavy metal ions. The electrode was successfully applied for determination of La3+ in binary mixtures. 相似文献
93.
Crystallography Reports - A new co-crystal compound of 4,4'-bipyridine and phenylsuccinic acid was synthesized and characterized by elemental analysis, infrared and ultraviolet–visible... 相似文献
94.
Azadeh Yahya-Meymandi Hamideh Nikookar Setareh Moghimi Mohammad Mahdavi Loghman Firoozpour Ali Asadipour Parviz Rashidi Ranjbar Alireza Foroumadi 《Journal of the Iranian Chemical Society》2017,14(4):771-775
Chromenoquinolines have been prepared via an efficient one-pot, multi-component reaction of 4-hydroxy coumarin, aqueous ammonia, dimedone and different aldehydes. 相似文献
95.
This article reports on a novel aptamer-based platform for the quantitation of urea by using an aptamer with high affinity and selectivity for urea. The surface of a glassy carbon electrode (GCE) was modified by drop casting a cocktail consisting of carbon nanotubes and reduced graphene oxide (rGO) decorated with platinum-gold nanoparticles. The urea aptamer was then immobilized on the nanocomposite via covalent conjugation. Cyclic voltammetry and electrochemical impedance spectroscopy were employed to trace the modification of the GCE. Binding of urea caused the aptamer to be folded, and this result in an inhibition of the interfacial charge transfer rate when using hexacyanoferrate as an electrochemical redox probe. The change in redox current was quantified by differential pulse voltammetry, typically at a working voltage of 0.22 V vs. Ag/AgCl. The assay has a 1.9 pM detection limit, and the response is linear up to 150 nM concentration of urea. The superior selectivity and affinity of aptamer-modified GCE makes it a most useful tool for analysis of urea present in very low concentrations. 相似文献
96.
A new diamine containing ferrocene group with preformed ether and amide units was prepared via reaction of 1,1′-ferrocenedicarbonyl chloride with two moles of 2,6-bis(5-amino-1-naphthoxy)pyridine. Polycondensation reactions of the prepared diamine with different aromatic and aliphatic diacid chlorides in the presence of trimethylchlorosilane (TMSCl) resulted in preparation of novel ferrocene modified poly(amide ether amide)s. The monomer and polyamides were characterized and the effect of trimethylchlorosilane (TMSCl) as activating agent on the polymerization reaction was studied. The physical and thermal properties of the polyamides including inherent viscosity, solubility, thermal stability and behavior, flame-retardancy and crystallinity of the polymers were studied. The polymers showed good thermal stability and flame-retardancy, and also improved solubility in polar aprotic solvents. 相似文献
97.
In this article, we investigate thermoluminescence properties of Nd3+ doped silicon dioxide optical fiber. The samples were exposed to 10 MV X-ray using a linear accelerator. The optical fiber was read out using Harshaw 3500 TLD reader. Nd-doped optical fiber displays a linear TL response for the absorbed dose. The sensitivity of Nd-doped optical fiber is 82.87 nC. mg–1 Gy–1, which is more sensitive to the other types of optical fiber. Nd+3-doped optical fiber displays clear single glow peak around 180°C. The peak shape method analysis reveals that the peaks obey general order kinetics. The activation energy of Nd-doped optical fiber is found to be nearly 0.5 eV less than TLD-100 (1.6 eV). Zeff of neodymium-doped silicon dioxide optical fiber is 13.48 that is near to the human bone. All of these TL characteristics indicate that Nd107-doped optical fiber as a potential TL dosimeter, for measuring photon irradiation. 相似文献
98.
Hajizadeh Alireza Bahramian Ahmad Reza Seifi Azadeh Naseri Iman 《Journal of Sol-Gel Science and Technology》2015,74(1):220-226
Journal of Sol-Gel Science and Technology - New carbon aerogels were prepared using Novolac sol as precursor. The elaboration process and the structural characterizations of these porous carbon... 相似文献
99.
Analysis of the magnetic losses in iron-based soft magnetic composites with MgO insulation produced by sol-gel method 总被引:3,自引:0,他引:3
Amir Hossein Taghvaei Azadeh Ebrahimi Kamal Janghorban 《Journal of magnetism and magnetic materials》2010,322(23):3748-3754
This work investigated the magnetic losses of heat treated iron-based soft magnetic composites with a thin MgO insulating layer produced by sol-gel method. The samples were characterized by energy dispersive X-ray spectroscopy, X-ray analysis and Fourier transform infrared spectroscopy. The results show that the surface of the powders contains a thin layer of MgO insulation. The loss results indicate that the hysteresis part for both the core loss and total loss factor was approximately the same for the MgO-insulated compacts and conventional SOMALOYTM samples with phosphate insulation after annealing at 600 °C. But the MgO-insulated compacts exhibited significantly lower eddy current contribution of both core loss and total loss factor with respect to SOMALOYTM samples after annealing. Also the contribution of eddy current in the iron particles for MgO insulated compacts (kp=0.91) was noticeably higher than this contribution for SOMALOYTM samples (kp=0.18) after annealing due to the higher electrical resistivity of the MgO-insulated compacts. 相似文献
100.
Amir Sabet Sarvestani Parviz Abdolmaleki Seyed Javad Mowla Faezeh Ghanati Emran Heshmati Zeinab Tavasoli Azadeh Manoochehri Jahromi 《Micron (Oxford, England : 1993)》2010,41(2):101-104
In order to evaluate the influence of static magnetic fields (SMF) on the progression of cell cycle as a monitor of presumptive genotoxicity of these fields, the effects of a 15 mT SMF on cell cycle progression in rat bone marrow stem cells (BMSC) were examined. The cells were divided into two groups. One group encountered SMF alone for 5 h continuously but the other group exposed with X ray before treatment with SMF. The population of cells did not show any significant difference in the first group but the second group that was exposed with acute radiation before encountering SMF showed a significant increase in the number of cells in G2/M phase. So SMF has intensified the effects of X ray, where SMF alone, did not had any detectable influence on cell cycle.These findings suggest that magnetic fields (MF) play their role by increasing the effects of genotoxic agents and because of the greater concentration of free radicals in the presence of radical pair producers, this effect is better detectable. 相似文献