排序方式: 共有47条查询结果,搜索用时 0 毫秒
21.
Mostafa Khoshsefat Narges Beheshti Gholam Hossein Zohuri Saeid Ahmadjo Somaye Soleimanzadegan 《Polymer Science Series B》2016,58(5):487-494
The Late transition metal catalysts based on Ni(II) and Co(II) were synthesized and their structure and activity in polymerization of ethylene were compared. Methylaluminoxane (MAO) was used as a co-catalyst. To discover the optimum polymerization conditions, the effect of polymerization temperature, monomer pressure, [Al]: [Ni] molar ratio and time of polymerization were studied. Activity of the catalysts was promoted by increasing of the monomer pressure. The viscosity average molecular weights Mv of the synthesized polymers using 1,2-bis(2,4,6-trimethyl phenyl imino) acenaphthene Nickel(II) dibromide were increased with increasing of the monomer pressure from 1 up to 6 bar which studied. Explicitly, the ortho-substituent has a significant effect on the catalyst behavior. Melting point and crystallinity of the obtained polyethylene using 1,2-bis(2,4,6-trimethyl phenyl imino) acenaphthene Nickel(II) dibromide catalyst were increased with enhancing monomer pressure. The optimum and stable structures were computed and some factors related to the activity were studied. Catalyst 1,2-bis(2,4,6-trimethyl phenyl imino) acenaphthene Nickel(II) dibromide had the highest activity with the highest quantities of dipole moment (18.29 Debye), charge of Mullikan on metal atom (1.48) and Sum of electronic and thermal Energies (–7906.52 e.u.). 相似文献
22.
Somaye Shahraki Fereshteh Shiri Hassan Mansouri-Torshizi Jafar Shahraki 《Journal of the Iranian Chemical Society》2016,13(4):723-731
In this study, the interaction between (2,2?-bipyridine)(pyrrolidinedithiocarbamato) platinum(II) nitrate, [Pt(bpy)(pyr-dtc]NO3, and human serum albumin (HSA) was investigated by various spectroscopic methods (UV–vis, fluorescence, CD and FT-IR) and molecular docking technique at three temperatures. UV–vis absorption spectroscopy showed that Pt(II) complex can denature the protein at moderate concentrations. The results of emission quenching at two temperatures has revealed that the quenching mechanism of Pt(II) complex with HSA was static quenching mechanism. Binding constants (K), binding site number (n) and corresponding thermodynamic parameters ?G?, ?H? and ?S? were calculated and revealed that hydrophobic forces played a major role when Pt(II) complex interacted with HSA. The binding distance (r) between above complex and HSA based on Förster?s theory of non-radiation energy transfer was calculated as 3.22 nm. Alterations of HSA secondary structure induced by complex were confirmed by FT-IR and CD measurements. Also, a molecular docking study was performed for identification of key structural features of binding of the Pt complex into the receptor and predicting bioactive conformers. Our results may provide valuable information to understand the mechanistic pathway of drug delivery and to pharmacological behavior of drug. 相似文献
23.
The intersection problem for a pair of 2- directed designs and 2- directed designs is solved by Fu in 1983 and by Mahmoodian and Soltankhah in 1996, respectively. In this paper we determine the intersection problem for 2- directed designs. 相似文献
24.
A facile and rapid multicomponent synthesis of pharmaceutically diverse 1H-isochromenes, 4H-chromenes, and ortho-aminocarbonitrile tetrahydronaphthalenes has been developed from benzaldehyde, malononitrile, and cyclohexanone. Three different methods from the same reactants, solvent, temperature, and catalyst lead to three products with excellent yields. All the reactions were followed with the Michael addition and cyclization. In this study, morpholine was used as an active metal-free base catalyst that increases the yields of products and decreases the time of reactions. 相似文献
25.
26.
Abdolmajid Bayandori Moghaddam Ali Mohammadi Somaye Mohammadi Danyal Rayeji Rassoul Dinarvand Mansoureh Baghi Roderick B. Walker 《Mikrochimica acta》2010,171(3-4):377-384
The oxidation of acetaminophen was studied at a glassy carbon electrode modified with multi-walled carbon nanotubes and a graphite paste. Cyclic voltammety, differential pulse voltammetry and square wave voltammetry at various pH values, scan rates, and the effect of the ratio of nanotubes to graphite were investigated in order to optimize the parameters for the determination of acetaminophen. Square wave voltammetry is the most appropriate technique in giving a characteristic peak at 0.52 V at pH 5. The porous nanostructure of the electrode improves the surface area which results in an increase in the peak current. The voltammetric response is linear in the range between 75 and 2000 ng.mL?1, with standard deviations between 0.25 and 7.8%, and a limit of detection of 25 ng.mL?1. The method has been successfully applied to the analysis of acetaminophen in tablets and biological fluids. 相似文献
27.
The role of folic acid in inducing of apoptosis by zinc(II) complex in ovary and cervix cancer cells
Yu Chuanrong Heidari Majd Mostafa Shiri Fereshteh Shahraki Somaye Karimi Pouya 《Molecular diversity》2022,26(3):1545-1555
Molecular Diversity - Herein, the synthesis, structure, binding affinity, cytotoxicity, and apoptotic properties of the new Zn(II) complex composed of folic acid and bipyridine ligands are... 相似文献
28.
Fe3O4 nanoparticles were coated with aminopropyltriethoxysilane and subsequently reacted with isatin to obtain imine‐bonded Fe3O4 nanoparticles. The addition of ZrOCl2?8H2O or CuCl2 led to the formation of complexes of Zr(IV)/isatin@Fe3O4 or Cu (II)/isatin@Fe3O4 as new magnetically separable catalysts. The synthesized catalysts were characterized using various techniques. These catalysts are shown to be efficient for chemo‐selective oxidation of sulfides to sulfoxides using hydrogen peroxide as oxidative agent. This system has many advantages, such as excellent level of reusability of magnetic catalysts, high yields, simplicity of separation of catalysts using an external magnet, environmental benignity and ease of handling. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献
29.
Meghdad Pirsaheb Yadolah Fakhri Mohammad Karami Rokhsareh Akbarzadeh Zahra Safaei Nazir Fatahi 《International journal of environmental analytical chemistry》2013,93(13):1353-1364
ABSTRACTThis study was conducted to investigate the residues of pyrethroid and organophosphorus pesticide in flour and breads which were collected from local markets in Kermanshah province, Iran. Four different types of breads and two types of flour samples with high distribution were taken from market and their residues of pesticides were measured. A simple dispersive liquid–liquid microextraction (DLLME) method with solidification of floating organic drop was developed for the measurement. The health risk of these pesticides on adults and children health was assessed by target hazard quotient (THQ) using Monte Carlo simulation (MCS) method. About, 15% and 11.1% of total samples contained detectable levels of deltamethrin and malathion, respectively. None of the tested samples showed any permethrin residue. The results from all samples showed that none of the pesticides exceeded the maximum residue limits (MRLs). About 85% of pesticide residue detections were observed in tropical and mild weather area which is due to high consumption rate of insecticides in these areas. The percentile 95% of THQ is due to bread ingestion content of deltamethrin which was 0.033 and 0.070 for the adults and children, respectively, while this value for malathion was found to be, 0.015 and 0.030, respectively. In the adults and children for both deltamethrin and malathion, the percentile 95% of THQ value were lower than 1 (acceptable level). The non-carcinogenic health risk assessment indicated that bread consumers in Kermanshah province are not at a considerable risk because of deltamethrin and malathion. 相似文献
30.
Maryam Mohammadi-Khanaposhtani Hoda Yahyavi Somaye Imanparast Fereshte Nazemi Harandi Mohammad Ali Faramarzi Alireza Foroumadi Bagher Larijani Mahmood Biglar Mohammad Mahdavi 《中国化学会会志》2020,67(5):856-863
Benzoylquinazolinone derivatives 3a–n were synthesized via a simple one-step reaction, and evaluated for in vitro α-glucosidase inhibitory activity. Compounds 3d , 3f–g , 3i , and 3m–n showed more inhibitory activity than standard drug acarbose (IC50 = 750.0 ± 1.5 μM), and among them, compound 3d displayed the highest α-glucosidase inhibitory activity (IC50 = 261.6 ± 0.1 μM). The kinetic analysis of the compound 3d revealed that this compound inhibited α-glucosidase in a competitive manner (Ki = 255 μM). The docking studies were applied to predict binding modes of the synthesized compounds in active site of α-glucosidase. 相似文献