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151.
Ali Reza Kazemizadeh Nahid Shajari Reza Shapouri Neda Adibpour Reza Teimuri-Mofrad 《Journal of the Iranian Chemical Society》2016,13(7):1349-1355
An isocyanide-based multicomponent reaction between cinnamic acid derivatives or 3-phenyl-2-propynoic acid, (N-isocyanimino)triphenylphosphorane, ferrocenecarbaldehyde, and dibenzylamine has been reported in excellent yields for the preparation of some new ferrocenyl-containing 1,3,4-oxadiazole derivatives. The anti-brucella activities of the products are investigated in in vitro and in vivo assays. 相似文献
152.
Ghassempour A Alizadeh R Najafi NM Karami A Römpp A Spengler B Aboul-Enein HY 《Journal of separation science》2008,31(13):2339-2345
The ability of crystalline degradation products (CDPs) of vancomycin as a chiral stationary phase was reported in a previous study for enantioselective separation of drugs, amino acids and agrochemical toxins by conventional LC column (250 x 4.6 mm). In this work, the potential of CDP of vancomycin for the enantiomeric separation in micro-LC (200 x 1 mm) has been studied. The obtained separation results are better than in our previous study with conventional LC columns. The enantiomers of D,L-phenylalanine, D,L-alanine, methyldopa, atropine and propranolol were used for this evaluation. Experiments have been carried out in a stainless steel tube that was packed with chiral silica particles of 3 and 12 microm diameters. Also, three different ratios of 3 and 12 microm silica particles were used for packing material of chiral columns and the effect on aspect ratio and resolving powers was compared. 相似文献
153.
In this study, a magnetically reusable artificial metalloenzyme has been constructed by co-immobilization of palladium nanoparticles as a strong oxidizing catalyst and laccase as an oxygen-activating enzyme into the cavities of magnetic mesocellular foams silica (Pd-Laccase@MMCF). The combination of Pd-Laccase@MMCF and hydroquinone (HQ) act as electron-transfer mediator system and make stepwise electron transfer from substrate to molecular oxygen. This catalyst system was used for the aerobic (i) oxidation of alcohols to the corresponding carbonyl compounds and (ii) dehydrogenation of 2-substituted-2,3-dihydroquinazolin-4(1H)-ones in phosphate buffer (0.1 M, pH 4.5, 4 mL)/THF (4%, 1 mL) as solvent under mild conditions. The co-immobilization of both laccase and Pd onto high surface area mesoporous support, high catalytic activity and magnetically separable and reusable make the present catalyst system superior to other currently available electron-transfer mediator systems. 相似文献
154.
Mathematical Notes - Certain orthogonal polynomials are involved in various problems occurring in probability, celestial mechanics, combinatorics, and other fields of theoretical and applied... 相似文献
155.
An inorganic–organic hybrid based on lanthanide clusters and Keggin type polyoxometalates (POMs) (Na[Nd (pydc‐OH)(H2O)4]3}[SiW12O40]) was used the first time as trinuclear catalyst for one pot synthesis of pyrazolo[4??,3?:5,6]pyrido[2,3‐d]pyrimidine‐diones, via two different four and five‐component reactions involving hydrazine hydrate, ethyl acetoacetate, aryl aldehydes, and 6‐amino‐1,3‐dimethyl uracil or barbituric acid with ammonium acetate as alternative materials in green condition. To evaluate potential application of the as‐made hybrid in adsorption and separation processes, nitrogen adsorption was performed at 77 K through simulation study. The hybrid catalyst was further characterized via powder X‐ray diffraction (PXRD) at room temperature which indicated the good phase purity of the catalyst. The results show that the catalytic activity of the hybrid catalyst has increased relative to each parent component due to the special interaction between Keggin anions and pydc‐OH ligands. 相似文献
156.
Nahid Shahabadi Soheila Kashanian Kani Shalmashi Hamideh Roshanfekr 《Applied biochemistry and biotechnology》2009,159(1):1-10
The [PtCl2(LL)] complex, as a cisplatin derivative, which LL is diamine chelate ligand (N,N-dimethyltrimethylendiamine), was synthesized and characterized by elemental analysis (CHN) mass, 1H, and 13C nuclear magnetic resonance techniques. Then the binding of this complex to calf thymus DNA was investigated by various physicochemical
methods such as spectrophotometric, circular dichroism, spectrofluorometric, melting temperature, and viscosimetric techniques.
Upon addition of the complex, important changes were observed in the characteristic UV–Vis bands (hypochromism) of calf thymus
DNA, increase in melting temperature and some changes in specific viscosity. Also, the fluorescence spectral characteristics
showed an increase in the fluorescence intensity of methylene blue–DNA solutions in the presence of increasing amounts of
metal complex, indicating PtCl2(LL) is able to displace the methylene blue bound to DNA but not as complete as intercalative molecules. The experimental
results showed that the platinum complex is bound to DNA non-intercalatively, and an outside binding is the preferred mode
of interaction. 相似文献
157.
A novel optical sensor based on a redox reaction for the determination of iodide has been developed. The optode membrane is constructed by immobilization of methyltrioctylammonium chloride on triacetylcellulose polymer. The exchange of chloride as counter ion with iodate in the membrane changes the color to yellow, when it is placed in acidic solution of iodide. The sensor can readily be regenerated by 0.1 mol L−1 NaOH in less than 15 s. The optode has a linear range of 3.94 × 10−6 to 5.51 × 10−5 mol L−1 of iodide ions with a limit of detection 7.44 × 10−7 mol L−1. The relative standard deviation for eight replicate measurements of 3.94 × 10−6 and 1.57 × 10−5 mol L−1 of iodide was 2.83 and 1.38%, respectively. The sensor was successfully applied to the determination of iodide in tablet, powdered milk and urine samples. 相似文献
158.
The aim of this paper is to derive a numerical scheme for solving stochastic differential equations (SDEs) via Wong-Zakai approximation. One of the most important methods for solving SDEs is Milstein method, but this method is not so popular because the cost of simulating the double stochastic integrals is high. For overcoming this complexity, we present an implicit Milstein scheme based on Wong-Zakai approximation by approximating the Brownian motion with its truncated Haar expansion. The main advantages of this method lie in the fact that it preserves the convergence order and also stability region of the Milstein method while its simulation is much easier than Milstein scheme. We show the convergence rate of the method by some numerical examples. 相似文献
159.
Huanyin?Chen Nahid?Ashrafi Marjan?Sheibani?AbdolyousefiEmail author 《Mediterranean Journal of Mathematics》2018,15(1):24
A ring R is a Garcia ring provided that the product of two regular elements is unit-regular. We prove that every regular element in a Garcia ring R is the sum/difference of an idempotent and a unit. Furthermore, we prove that every regular element in a weak Garcia ring is the sum of an idempotent and a one-sided unit. These extend several known theorems on (one-sided) unit-regular rings to wider classes of rings with sum summand property. 相似文献
160.