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排序方式: 共有256条查询结果,搜索用时 320 毫秒
111.
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
112.
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
113.
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
114.
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
115.
A. Nowroozi P. Mohammadzadeh Jahani N. Asli H. Hajiabadi S. Dahmardeh H. Raissi 《International journal of quantum chemistry》2012,112(2):489-497
Quantum chemical study of N‐formylformamide (NFF) was carried out at various theoretical levels and the determinate equilibrium conformations were recomputed at the high level ab initio methods such as G2MP2, G2, G3, and complete basis set (CBS)‐QB3. The computational results reveal that the amide resonance and intramolecular hydrogen bonding are two superior factors in determining the most stable conformation of diamide (DA) and amide–imidic (AI) acid tautomers, respectively. The evaluation of hydrogen bond energies predicts that the hydrogen bond (HB( strength of NFF is weaker than the malonaldehyde (MA). But the results of atoms in molecules (AIM(, natural bond orbital (NBO), and geometrical parameters are given a different order, EHB(NFF) > EHB(MA). Although the bond average energies of tautomerization process emphasized on more stability of AI tautomer, but our theoretical calculations reveal that the DA conformers are more stable than the AI ones. The population analyses of equilibrium conformations by NBO method also predict that the origin of tautomeric preference is mainly because of the electron delocalization of amide functional group, especially LP(N)→ π*C?O charge transfer. © 2010 Wiley Periodicals, Inc. Int J Quantum Chem, 2012 相似文献
116.
H. Hajiabadi A. Nowroozi M. Hasani P. Mohammadzadeh Jahani H. Raissi 《International journal of quantum chemistry》2012,112(5):1384-1391
MP2 study of O? H…N intramolecular hydrogen bond (IMHB) in 3‐imino‐propen‐1‐ol and its derivatives were performed and their IMHB energies were obtained using the related rotamers and open‐close methods. Also the topological properties of electron density distribution and charge transfer energy associated with IMHB were gained by quantum theory of atoms in molecules and natural bond orbital theory, respectively. The computational results reveal that the related rotamers method energies are well correlates with geometrical parameters, topological parameters at hydrogen bond and ring critical points, integrated properties, proton transfer barrier and charge transfer energy of O? H…N unit. Surprisingly, it was found that the open‐close hydrogen bond energies cannot represent good linear correlations with these parameters. Consequently, we extrapolate a number of equations that can be used in estimation of O? H…N IMHB energy in complex biological systems. © 2011 Wiley Periodicals, Inc. Int J Quantum Chem, 2012 相似文献
117.
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
118.
In this article, we prove the existence of stem covers for crossed modules, which generalizes the works of Schur (1904) [20] and Jones (1973) [11] in group theory. We also, using projective presentations, determine the structure of all stem covers of crossed modules whose second homologies are finite and, using this result, we give several results concerning them, which extend the classical ones for stem covers of groups. 相似文献
119.
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
120.
Akbar Golchin Parisa Rezaei Hossein Mohammadzadeh 《Czechoslovak Mathematical Journal》2009,59(3):595-611
By a regular act we mean an act such that all its cyclic subacts are projective. In this paper we introduce strong (P)-cyclic property of acts over monoids which is an extension of regularity and give a classification of monoids by this property
of their right (Rees factor) acts. 相似文献