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排序方式: 共有175条查询结果,搜索用时 20 毫秒
81.
Li Yicheng Moradi Iman Kalantar Mahdi Babadi Elmira Malekahmadi Omid Mosavi Amirhosein 《Journal of Thermal Analysis and Calorimetry》2021,144(6):2587-2603
Journal of Thermal Analysis and Calorimetry - Nanofluid refers to the mixture of fluid and solid nanoparticles. If this mixture contains more than one NP or fluid, it is called “hybrid... 相似文献
82.
Structural Chemistry - The detection methods used to analyze abused drugs should be sensitive sufficiently. Here in, we propose carbon nanotube (CNT) functionalized with COOH and CONHCH3 groups as... 相似文献
83.
Nouria Boussalah Rachid Touzani Faiza Souna Iman Himri Mohammed Bouakka Abdelkader Hakkou Said Ghalem Sghir El Kadiri 《Journal of Saudi Chemical Society》2013,17(1):17-21
Series of functional multidendate ligands based on pyrazole and amino acid derivatives were prepared in good and excellent yields (75–5%) by condensation of one equivalent of amino acid ester hydrochloride substrates with two equivalents of (3,5-dimethyl-1H–pyrazol-1-yl)methanol. These tridentate functionalized compounds and their starting materials were screened for their antifungal activities against Fusarium oxysporum f.sp. albedinis and the yeast of Saccharomyces cerevisiae. Considerable activities were recorded with respect to the two studied microorganisms. 相似文献
84.
Alireza Feizbakhsh Ali Aghassi Ali Ehsani Malihe A. Jamaat Ali Naeemy Iman Danaee 《中国化学会会志》2012,59(9):1086-1093
In this study we investigated the electrocatalytic oxidation of anti‐inflammatory drug (paracetamol) on Nickel and Nickel–copper alloy modified glassy carbon electrodes (GC/Ni and GC/NiCu) in alkaline solution. These electrodes prepared by galvanostatic method and different electrochemical techniques such as cyclic voltammetry and chronoamperometry were used to track the oxidation process and its kinetics. From Voltammetric studies we concluded that in the presence of drugs the anodic peak current of low valences Nickel species increased, followed by a decrease in the corresponding cathodic current peak. This indicates that drugs were oxidized on the redox mediator which was immobilized on the electrode surface via an electrocatalytic mechanism. Using Laviron's equation, the values of α and ks for the immobilized redox species were determined. The anodic peak currents show linear dependency with the square root of scan rate. This behavior is the characteristic of a diffusion controlled process. Under the CA regime the reaction followed a Cottrellian behavior and the diffusion coefficient of paracetamol was found in agreement with the values obtained from CV measurements. 相似文献
85.
Iman?Jabbari Zahir Abadi Omid?Sadeghi Hamid?Reza?Lotfizadeh Zhad Najmeh?Tavassoli Vahid?Amani Mostafa?M.?AminiEmail author 《Journal of Sol-Gel Science and Technology》2012,61(1):90-95
Nanoporous silica SBA-15 was prepared to evaluate its application as an oral drug delivery system. A series of surface-functionalized
nanopore materials as efficient clarithromycin delivery carriers was investigated. An efficient pH-responsive carrier system
was constructed by hydrogen bond interaction between carboxyl and hydroxyl groups in the clarithromycin and the amine group
in modified SBA-15. HPLC analyses of clarithromycin were run on a C18 column using a mobile phase comprised of potassium dihydrogen phosphate, acetonitrile and methanol (30:40:30, v/v/v). Active
molecules such as clarithromycin could be stored and released from the pore voids of SBA-15 by changing the pH. The amount
of clarithromycin stored in the pores of nanoporous silica based on TREN [tris(2-aminoethyl) amine]-modified SBA-15 rods was
up to 46 ± 4.8 wt% at pH 8. In addition, when the pH was below 4, clarithromycin was steadily released from the pores of SBA-15
(up to 97 wt% in simulated gastric medium). 相似文献
86.
Kyu Ok Jeon Dinesh Rayabarapu Alan Rolfe Kelly Volp Iman Omar Paul R. Hanson 《Tetrahedron》2009,65(26):4992-7773
The development of a ring-opening metathesis/ring-closing metathesis/cross-metathesis (ROM-RCM-CM) cascade strategy to the synthesis of a diverse collection of bi- and tricyclic sultams is reported. In this study, functionalized sultam scaffolds derived from intramolecular Diels-Alder (IMDA) reactions undergo metathesis cascades to yield a collection of tricyclic sultams. Additional appendage-based diversity was achieved by utilizing a variety of CM partners. 相似文献
87.
Dynamical behavior of particles in a Paul trap in the presence of damping force has been investigated. Position of trapped ions as a function of time, ion trajectories and the phase space curves considering the effect of the damping force were obtained. Four regions of stability for r and z components with the damping force as well as the maximum value of q when U = 0 for the first region, namely qmax, versus damping factor k were computed using the fourth-order Runge–Kutta method. Comparisons were made with the corresponding stability diagrams without the damping force effect recently published in the literature. The third and fourth stability regions in the presence of the damping force, the curve of qmax as a function of k and the related equation are reported for the first time. 相似文献
88.
Iman Maleksaeedi Behzad Esazadeh Khiav Masoud Bakhshi Germi Noradin Ghadimi 《Complexity》2015,21(1):187-194
This article proposed a new hybrid algorithm for solving power flow tracing (PFT) through the comparison by other techniques. This proposed hybrid strategy in detail discuses over the achieved results. Both methods use the active and reactive power balance equations at each bus to solve the tracing problem, where the first method considers the proportional sharing assumption and the second one considers the circuit laws to find the relationship between power inflows and outflows through each line, generator, and load connected to each bus of the network. Both algorithms are able to handle loop flow and loss issues in tracing the problem. A mathematical formulation is also introduced to find the share of each unit in provision of each load. These algorithms are employed to find the producer and consumer's shares on the cost of transmission for each line in different case studies. As the results of these studies show, both algorithms can effectively solve the PFT problem. © 2014 Wiley Periodicals, Inc. Complexity 21: 187–194, 2015 相似文献
89.
Samad Shoghpour Bayraq Ahmad Nikseresht Iman Khosravi 《Phosphorus, sulfur, and silicon and the related elements》2013,188(9):1236-1243
Abstract Ammonium molybdate, (NH4)6Mo7O24·4H2O, is found to be an efficient and selective catalyst for the oxidation of thiols to corresponding disulfides using potassium bromate in aqueous acetonitrile as the solvent. Among various solvents tested, CH3CN/H2O showed better results in terms of the reaction yield and rate. In the absence of (NH4)6Mo7O24·4H2O, the oxidation reaction is not selective for the formation of disulfides. The catalyst can be easily recovered after completion of the reaction and reused without any significant loss of its activity. [Supplementary materials are available for this article. Go to the publisher's online edition of Phosphorus, Sulfer, and Silicon and the Related Elements for the following free supplemental files: Additional text and figures.] 相似文献
90.
Furio Corà Maria Alfredsson Carolyn M Barker Rob G Bell Martin D Foster Iman Saadoune Alexandra Simperler C.Richard A Catlow 《Journal of solid state chemistry》2003,176(2):496-529
We present a thorough computational study of transition metal-doped zeolite and aluminophosphate (AlPO) frameworks. The structural and electronic chemistry of the dopants is examined with ab initio quantum mechanical calculations, and the results correlated with the Brønsted and Lewis acid strength, and with the redox potential of the dopant ions in the framework. The energetics of doping is provided, and is employed to analyze the mode of dopant incorporation, and its site ordering in the microporous framework. In total, 23 dopant ions are examined in the isostructural framework of chabasite and AlPO-34. These cover most of the isomorphous framework replacements known to occur experimentally, but also framework replacements that have not yet been achieved. In this case, ab initio modeling techniques are employed in a predictive way. Finally, we present a computational study of the alkene epoxidation on titanosilicates, that covers the whole catalytic cycle. 相似文献