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1.
Neda Choodari Milani Yazdan Maghsoud Mahdieh Hosseini Abouzar Babaei Hamidreza Rahmani Stephen Mark Roe Khodayar Gholivand 《应用有机金属化学》2020,34(4):e5526
Seven novel complexes (C1–C7) were synthesized by the interaction between Cu(I) metal cation, L1, L2, L3, X and PPh3, where L1–L3 are derivatives of ((pyridine-2-ylmethylene)amino)phenol imine ligands and X = Cl−, Br−, I−, NCS−. All the complexes were characterized using infrared, 1H NMR and 31P NMR spectroscopies. The crystal structures of C1–C7 were also determined using single-crystal X-ray diffraction. The organization of the crystal structures and the intermolecular interactions are discussed. The supramolecular assemblies are driven by cooperative π…π interactions and hydrogen bonds, followed by CH…π linkages. The potential anticancer effect of C1–C7 was assessed for human glioblastoma cells using several anticancer experiments, which showed that these complexes have marked anticancer property against U87 cells. It was also found that the minimum and maximum anticancer effects are shown by C3- and C4-treated samples, respectively. Furthermore, theoretical approaches were used to investigate the nature of metal–ligand interactions which suggest a closed-shell and electrostatic character for Cu…N, Cu…P and Cu…X bonds. 相似文献
2.
Three dinuclear copper(II) complexes, [Cu2(L1)2(μ-ox)](ClO4)2?2(CH3CN), [Cu2(L2)2(μ-ox)](ClO4)2?H2O, and [Cu2(L3)2(μ-ox)](ClO4)2 where ox = oxalato; L = N,N-dimethyl,N′-benzylethane-1,2-diamine, L1, N,N-diethyl,N′-benzylethane-1,2-diamine, L2, N,N-diisoprophyl,N′-benzylethane-1,2-diamine, L3, were prepared and characterized by elemental analyses, spectral (IR, UV–Vis) data and molar conductance measurements. The crystal structures of [Cu2(L1)2(μ-ox)](ClO4)2?2(CH3CN) and [Cu2(L3)2(μ-ox)](ClO4)2 have been determined by single-crystal X-ray analysis. Solvatochromic behaviors were investigated in various solvents, showing positive solvatochromism. The effect of steric hindrance around the copper ion imposed by N-alkyl groups of the diamine chelates on the solvatochromism property of the complexes is discussed. Solvatochromism was also studied with different solvent parameter models using stepwise multiple linear regression method. 相似文献
3.
Mohammadreza Amini Abouzar Samimi Asra Mirzavandi 《International Journal of Electronics》2016,103(4):747-764
Transmission time optimisation is one of the key considerations of cognitive network design. There are many studies in cognitive radio networks (CRNs) focusing on finding the best transmission time for secondary users (SUs) to maximise transmission or energy efficiency. While longer sensing duration leads to a higher sensing accuracy and causes less interference, the SU spends less time for transmission and more energy on sensing spectrum. On the other hand, when the transmission duration becomes longer, although the SU has more opportunities to access the channel, it may encounter higher interference due to primary user (PU) returns and the probability of collision becomes higher. In this article, in a decentralised slotted protocol for CRN, the SU spectrum access is proved as a renewal process, then the interference due to PU return during SU transmission, the missed opportunities due to waiting for the channel to become idle and the energy consumed by the SU in the whole spectrum access process including idling energy, transmission energy and sensing energy consumption are formulated and integrated into newly defined efficiency to obtain the optimum transmission time and waiting time. 相似文献
4.
A. Poghossian S. Ingebrandt M.H. Abouzar M.J. Schöning 《Applied Physics A: Materials Science & Processing》2007,87(3):517-524
The possibilities and limitations of a direct electrical detection of charged macromolecules using a field-effect-based sensor
platform is evaluated, mainly focusing on capacitive EIS (electrolyte-insulator-semiconductor) devices. The experimentally
obtained results on the detection of DNA immobilisation and hybridisation as well as the monitoring of layer-by-layer adsorbed
charged polyelectrolyte (PE) multilayers have been discussed by using two basic possible mechanisms of signal generation,
namely the intrinsic charge of the macromolecules and the charge redistribution within the intermolecular spaces or in the
multilayer. The effects of the layer-by-layer adsorption conditions (unbuffered and pH buffer solution), and the number and
polarity of charged layers on the sensor response have been systematically investigated by means of capacitance–voltage (C–V),
constant–capacitance (ConCap) and impedance spectroscopy (IS) methods.
PACS 82.47.Rs; 82.80.Fk; 85.30.Tv; 87.15.Kg; 87.14.Gg 相似文献
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6.
Hossein Samimi 《International Journal of Communication Systems》2011,24(1):14-26
A new composite channel model is proposed for the performance analysis of shadowed fading channels. This model is represented as a mixture of generalized Gamma (GG) multipath fading and lognormal shadowing. GG distribution includes the Rayleigh, Nakagami, and Weibull as special cases; hence the presented model, which is referred to as GG‐L, is a generic model that covers many well‐known composite fading models, including the Rayleigh–lognormal (R‐L), Nakagami–lognormal (N‐L), and Weibull–lognormal (W‐L). The main drawback of the lognormal‐based composite models is that the composite probability density function (PDF) is not in closed form, thereby making the performance evaluation of communication links in these channels cumbersome. To bypass this problem, an approximation method is developed which makes it possible to derive a closed‐form, analytical expression for GG‐L composite distribution. The proposed method only needs the mean and the variance of the underlying lognormal distribution, and hence, bypasses the required complicated integration needed to calculate the PDF of the received signal envelope in GG‐L channel. Based on this method, the most statistical characteristics, such as cumulative density function (CDF) and moments of the GG‐L composite distribution, are derived and used for the performance analysis of a single receiver operating over GG‐L fading channel. Copyright © 2010 John Wiley & Sons, Ltd. 相似文献
7.
In the highly competitive business environment of today, the cost to attract new customers is much higher than the cost required to maintain the existing ones. To keep the balance between the acquisition rate and defection rate through executing offensive and defensive marketing policies, it is required to have real time information using an efficient method to monitor customer loyalty. The relationship between customer loyalty and customer satisfaction should be kept in mind when one develops a method for loyalty monitoring. This paper presents several control charts classified in two groups based on the scale used to assess customer loyalty. In the first group of control charts, customer loyalty is considered as a binary random variable modeled by Bernoulli distribution whilst in the second group, an ordinal scale is considered to report loyalty level. Performance comparison of the proposed techniques using ARL criterion indicates that chi‐square and likelihood‐ratio control charts developed based on Pearson chi‐square statistic and ordinal logistic regression model respectively are able to rapidly detect the significant changes in loyalty behavior. To show how to apply the procedures and how to interpret their results, two illustrative synthetic cases are also explained. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献
8.
Dehkordi S. Saeid Saei Albadi Jalal Jafari Abbas Ali Samimi Heshmat Allah 《Research on Chemical Intermediates》2021,47(6):2527-2538
A copper-based magnetic nanocatalyst has been prepared by co-precipitation method and characterized by FESEM, EDS, TEM, XRD, XRF, ICP–OES, FTIR, and BET analysis. This new nanocatalyst displays a good activity toward the aerobic oxidation of a wide range of alcohols in water. Moreover, it is recyclable up to five following runs by simple filtration without any significant loss of its catalytic activity.
相似文献9.
Alipour Lalami Ali Hassanzadeh Afrouzi Hamid Moshfegh Abouzar 《Journal of Thermal Analysis and Calorimetry》2019,136(5):1959-1975
Journal of Thermal Analysis and Calorimetry - An incompressible preconditioned lattice Boltzmann method (IPLBM) is proposed to investigate the fluid flow and heat transfer characteristics of... 相似文献
10.
Heshmat A. Samimi Manouchehr Mamaghani Khalil Tabatabaeian 《Journal of heterocyclic chemistry》2008,45(6):1765-1770