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71.
The charge transfer interactions between the seproxetine (SRX) donor and π-electron acceptors [picric acid (PA), dinitrobenzene (DNB), p-nitrobenzoic acid (p-NBA), 2,6-dichloroquinone-4-chloroimide (DCQ), 2,6-dibromoquinone-4-chloroimide (DBQ), and 7,7′,8,8′-tetracyanoquinodi methane (TCNQ)] were studied in a liquid medium, and the solid form was isolated and characterized. The spectrophotometric analysis confirmed that the charge–transfer interactions between the electrons of the donor and acceptors were 1:1 (SRX: π-acceptor). To study the comparative interactions between SRX and the other π-electron acceptors, molecular docking calculations were performed between SRX and the charge transfer (CT) complexes against three receptors (serotonin, dopamine, and TrkB kinase receptor). According to molecular docking, the CT complex [(SRX)(TCNQ)] binds with all three receptors more efficiently than SRX alone, and [(SRX)(TCNQ)]-dopamine (CTcD) has the highest binding energy value. The results of AutoDock Vina revealed that the molecular dynamics simulation of the 100 ns run revealed that both the SRX-dopamine and CTcD complexes had a stable conformation; however, the CTcD complex was more stable. The optimized structure of the CT complexes was obtained using density functional theory (B-3LYP/6-311G++) and was compared.  相似文献   
72.
Three metal complexes of Gd (III), Pr (III) and Ru (III) metal ions with Schiff base ligand (H2L) (prepared through l:2 condensation of dibenzoyl methane and anthranilic acid) were prepared and characterized using various physio-chemical methods like: elemental analyses, IR, mass spectrometry, magnetic moment, 1H NMR, SEM and TG/DTG thermal analysis. The analytical and spectroscopic tools showed that the complexes had composition of ML type with octahedral geometry. The mass spectra gave the possible molecular ion peaks of the Schiff base ligand and three metal chelates. The 1H NMR data supported the IR finding that the ligand coordinated to the metal ions via carboxylate proton displacement. Thermal analysis (TG/DTG) was utilized to differentiate between coordinated and hydrated water molecules. The Schiff base (H2L) and its metal complexes have been screened for their antibacterial activity against Gram (+) bacteria (Streptococcus aureus and Bacillis subtilis), Gram (−) bacteria (Salmonella typhimurium and Escherichia coli) and two fungi (Aspergillus fumigatu and Candida albicans) organisms by agar diffusion method. The anticancer activity was screened against human breast cancer cell line (MCF-7). The H2L ligand and its metal chelates were docked using MOE 2008 software with crystal structure of Gram (+) bacteria: Staphylococcus aureus (PDB ID: 3Q8U) and Gram (−) bacteria: Salmonella typhimurium (PDB ID: lDZR) to identify the binding orientation or conformation of the complex in the active site of the protein.  相似文献   
73.
The metal ions Co(II), Ni(II), Zn(II), Zr(IV), and Hg(II) reacted with synthesized Schiff base (L) in mole ratios 1:2 (M:L) formed metal complexes. The structure of the prepared compounds was identified based on the data obtained from elemental analyses, magnetic measurement, melting point, conductivity, Fourier-transform infrared, UV–Vis., nuclear magnetic resonance spectroscopy, X-ray diffraction (XRD) spectra, and thermal analysis (TG/DTG [thermogravimetric/differential thermal analysis]). The results indicate that the L bound as bidentate through the oxygen atom of the hydroxyl group and nitrogen atom of the azomethine group with the metal ions and the complexes is electrolyte in nature. TG/DTG studies confirmed the chemical formula for complexes. The kinetic and thermodynamic parameters such as E*, ΔH*, ΔS*, and ΔG* were determined by using Coats–Redfern and Horowitz–Metzger methods at n = 1 and n ≠ 1. The XRD patterns exhibited a semicrystalline nature lying between the amorphous and crystalline nature for L, (D), and (E), but the complexes (A), (B), and (C) possessed a crystalline character. Density functional theory confirmed the structural geometry of the complexes. In vitro antimicrobial activities were performed for L and its metal complexes.  相似文献   
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75.
Wireless Personal Communications - Current wireless networks are based on unicast routing protocol derived from wired networks. The purpose of this paper is to implement and to evaluate...  相似文献   
76.
Journal of Radioanalytical and Nuclear Chemistry - This study aimed to synthesize a new pyrimidine derivative with a good synthesis yield of 87% to act as a new cancer marker after radiolabeling...  相似文献   
77.
The forward–backward splitting technique is a popular method for solving monotone inclusions that have applications in optimization. In this paper, we explore the behaviour of the algorithm when the inclusion problem has no solution. We present a new formula to define the normal solutions using the forward–backward operator. We also provide a formula for the range of the displacement map of the forward–backward operator. Several examples illustrate our theory.  相似文献   
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79.
We propose, end-to-end (EtE), a novel EtE localized routing protocol for wireless sensor networks that is energy-efficient and guarantees delivery. To forward a packet, a node s in graph G computes the cost of the energy weighted shortest path (SP) between s and each of its neighbors in the forward direction towards the destination which minimizes the ratio of the cost of the SP to the progress (reduction in distance towards the destination). It then sends the message to the first node on the SP from s to x: say node x′. Node x′ restarts the same greedy routing process until the destination is reached or an obstacle is encountered and the routing fails. To recover from the latter scenario, local minima trap, our algorithm invokes an energy-aware Face routing that guarantees delivery. Our work is the first to optimize energy consumption of Face routing. It works as follows. First, it builds a connected dominating set from graph G, second it computes its Gabriel graph to obtain the planar graph G′. Face routing is invoked and applied to G′ only to determine which edges to follow in the recovery process. On each edge, greedy routing is applied. This two-phase (greedy–Face) EtE routing process reiterates until the final destination is reached. Simulation results show that EtE outperforms several existing geographical routing on energy consumption metric and delivery rate. Moreover, we prove that the computed path length and the total energy of the path are constant factors of the optimal for dense networks.
Essia Hamouda (Corresponding author)Email:
Nathalie MittonEmail:
Bogdan PavkovicEmail:
David Simplot-RylEmail:

Essia Hamouda   received the BSc and the MS degree in Industrial and Systems Engineering from the Ohio State University and the University of Florida, respectively. She received a PhD in Computer Science from the University of California Riverside. Her research interests are in the areas of sensor and mobile ad hoc networks and performance evaluation of computer networks. Nathalie Mitton   is currently an INRIA full researcher. Her research interests are mainly focused on theoretical aspects of self-organization, self-stabilization, energy efficient routing and neighbour discovery algorithms for wireless sensor networks as well as RFID middlewares. She is involved in several program and organization committees such as ADHOC NOW 2009, SANET 2008 and 2007. Bogdan Pavkovic   received a MSc in Microprocessor and computer electronics from the Faculty of Technical Sciences in Novi Sad, University of Novi Sad in May of 2009. From May to December of 2009 he was an intern at INRIA, Lille—Nord Europe, France. His research interest include embedded systems and applied electronic, robotics and automated vehicles, sensor and mobile ad hoc networks and RFID technologies. David Simplot-Ryl   received the PhD degree in computer science in 1997 from the University of Lille, France. He is now a professor at the University of Lille 1 and head of the POPS research team at the INRIA research centre Lille—Nord Europe. His research interests are in the areas of sensor and mobile ad hoc networks, mobile and distributed computing, and RFID technologies. He is editor and guest editor of several journals, cochair of conferences and workshop. Since 2008, he is scientific deputy of the INRIA research centre Lille—Nord Europe.   相似文献   
80.
The performance of space-time transmit diversity is examined in a multiuser direct-sequence code-division multiple-access (DS-CDMA) system over fast- and slow-fading channels. The underlying space-time system employs transmit antennas and receive antennas at the mobile user and receiver base station, respectively. We consider the performance of the space-time multiuser system when using the linear decorrelator detector to combat the effect of multiuser interference. In our analysis, we derive a closed-form expression for the probability of bit error for both fast- and slow-fading channels. These theoretical results are shown to be very accurate when compared to system simulations. Both simulations and theoretical results prove that, regardless of the system load, the full diversity order of for fast-fading channels and for slow-fading channels is always maintained, and only a signal-to-noise ratio (SNR) loss is incurred. This SNR loss is proved to be a function of only the number of users (i.e., level of interference) and independent of the number of transmit and/or receive antennas. Using our theoretical results, we show that the loss in SNR from the single-user bound can be well approximated by , where represents the level of multiuser interference.  相似文献   
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