Energy-Efficient Routing Protocol Based on Adaptive Soft Thresholding for Wireless Sensor Networks

Wireless Personal Communications - In this paper, a low-energy adaptive clustering hierarchy (LEACH)-based routing protocol for wireless sensor networks (WSNs) is presented. The proposed...     

Maximal atom–photon entanglement in a double-$$\Lambda $$ quantum system

The atom–photon entanglement of a dressed atom and its spontaneous emission in a double-\(\Lambda \) closed-loop atomic system is studied under multi-photon resonance condition. It is shown that even in the absence of quantum interference due to the spontaneous emission, the von Neumann entropy is phase-sensitive and it can be controlled by either intensity or relative phase of the applied fields. It is demonstrated that for the special case of Rabi frequency of the applied fields, the system is maximally entangled. Moreover, an open-loop configuration is considered, and it is shown that the degree of entanglement can be controlled by intensity of the applied fields. Furthermore, in electromagnetically induced transparency condition, the system is disentangled. Such a system can be used for quantum information processing via entanglement using optical switching.     

Ammonia – assisted Synthesis Method for CoTiO3 Nanoporous Matrix

The theory of an "ammonia fountain" was developed to synthesize a CoTiO₃ nanoporous matrix using a modified co-precipitation method at the interface of the aqueous solution and the saturated NH₃ atmosphere. On the basis of this theory, for the first time, a new assumption was expanded to show the regular (re)arrangement of metal cations near to the surface of the solution. The morphology of the CoTiO₃ phase was observed using SEM. The result indicates the nano-narrow formation of CoTiO₃ particles. The size of the particles was calculated at about 27 nm. From the XRD patterns, the formation of cobalt titanate nanoparticles was confirmed.     

Semi‐aromatic polyimide/Ag nanocomposite derived from vanillin

The development of bioprecursor polyimide/Ag nanocomposites (PI/Ag NCs) is reported in this investigation. Semiaromatic bioprecursor PI was successfully synthesized through direct polycondensation reaction between aromatic diamine containing pyridine ring and aliphatic dianhydride. Aromatic diamine as a monomer was synthesized using a renewable resource, vanillin. The main attractive aspects of this PI are the renewable origin of the diamine, presence of pyridine and high aromatic rings content, as well as aliphatic content on the polymer backbone. The structure of synthesized monomer and PI were proven by FTIR, and nuclear magnetic resonance. The PI/Ag NCs containing 3, 5, and 7 wt % of Ag nanoparticles (Ag NPs) were prepared through solution technique and the resulting NCs were characterized by Fourier transform infrared spectra, wide angle X‐ray diffraction, transmission electron microscopy (TEM), and thermogravimetric analysis (TGA). TEM results showed that the Ag NPs were dispersed homogeneously in the PI matrix on nanoscale. TGA results indicated improving in thermal properties of PI/Ag NCs compared to the neat PI due to the interaction between the PI matrix and the Ag NPs. Antibacterial activity of PI/Ag NCs was tested by the disk diffusion method using Escherichia coli as model strain of gram‐negative bacteria. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016 , 133, 44001.     

The combination effects of trivalent gold ions and gold nanoparticles with different antibiotics against resistant Pseudomonas aeruginosa

Despite much success in drug design and development, Pseudomonas aeruginosa is still considered as one of the most problematic bacteria due to its ability to develop mutational resistance against a variety of antibiotics. In search for new strategies to enhance antibacterial activity of antibiotics, in this work, the combination effect of gold materials including trivalent gold ions (Au³⁺) and gold nanoparticles (Au NPs) with 14 different antibiotics was investigated against the clinical isolates of P. aeruginosa, Staphylococcus aureus and Escherichia coli. Disk diffusion assay was carried out, and test strains were treated with the sub-inhibitory contents of gold nanomaterial. Results showed that Au NPs did not increase the antibacterial effect of antibiotics at tested concentration (40 μg/disc). However, the susceptibility of resistant P. aeruginosa increased in the presence of Au³⁺ and methicillin, erythromycin, vancomycin, penicillin G, clindamycin and nalidixic acid, up to 147 %. As an individual experiment, the same group of antibiotics was tested for their activity against clinical isolates of S. aureus, E. coli and a different resistant strain of P. aeruginosa in the presence of sub-inhibitory contents of Au³⁺, where Au³⁺ increased the susceptibility of test strains to methicillin, erythromycin, vancomycin, penicillin G, clindamycin and nalidixic acid. Our finding suggested that using the combination of sub-inhibitory concentrations of Au³⁺ and methicillin, erythromycin, nalidixic acid or vancomycin may be a promising new strategy for the treatment of highly resistant P. aeruginosa infections.     

Rapid Analysis of Styrene in Drinking Water and Tea Samples Using Dispersive Liquid-Liquid Microextraction Combined with Liquid Chromatography-Ultraviolet Detection

In this project, a simple, low-cost and rapid procedure based on dispersive liquid–liquid microextraction (DLLME) technique coupled with high performance liquid chromatography-ultraviolet detector (HPLC-UV) has been used for the extraction and determination of styrene in aqueous solutions. Several factors, such as type of extraction and dispersive solvents and their volumes, salt addition, and pH were optimized. Under optimal conditions, the recoveries of styrene for tea and water samples spiked with 10 and 15 ng mL^?1 were in the range of 91.4–97.8 %, whereas the temperature was set at 0, 4, 20, 70 and 91 °C for 15, 30, 60, 1440, and 14,400 min. The linear range was obtained in the interval of 1.86–50 ng mL^?1. The limits of detection (S/N = 3) and quantitation (S/N = 10) were 0.6 and 1.86 ng mL^?1, respectively. The relative standard deviations (RSDs) for three replicated analysis of styrene in aqueous samples ranged from 0.01 to 0.3 %.     

Validation of a Simple Spectrophotometric Method for the Measurement of Quaternary Ammonium Compound Residue Concentrations in Food Production Facility

Quaternary ammonium compound (QAC) residues can increase with each application and build up over a period of time during sanitation of food plants. Therefore, it is crucial to establish a simple but accurate method for routine measurement of QAC residues in food plants. In this study, a spectrophotometric method was validated and applied for the quantification of QAC residues on stainless steel surfaces. This method was based on the formation of a colored ion pair between the quaternary ions and Eosin-Y in the presence of Triton X-100. QAC residues were recovered from surfaces using swabs and were subsequently sonicated, and the isolated extracts were analyzed with a spectrophotometer (535 nm). The method was shown to be selective in the presence of interfering substances, and a linear relationship between the absorbance and concentration of QACs was detected in the concentration range from 0.5 to 10 mg?L^?1 (r ²?>?0.99). The limit of detection and limit of quantitation were 0.53 and 1.77 mg?L^?1, respectively. Satisfactory accuracy (93–97 %) and precision (relative standard deviation (RSD)?<?2.7 %) were obtained for the method. Assessment of the effect of swabbing protocol on the recovery, repeatability and intermediate precision of the method revealed that the mean recovery of residues was 90 %. Moreover, the percent RSD was less than 8.8 and 9.4 % for repeatability and intermediate precision, respectively. QAC residues were found to be stable on stainless steel surfaces for at least 6 days following deposition, a treatment that could be a potential risk especially in dry cleaning processes.     

Thin film graphene oxide membrane: Challenges and gas separation potential

Graphene oxide membranes were prepared by vacuum and pressurized ultrafiltration methods on the 12% modified Polyacrylonitrile (12mPAN) substrate to specify challenges, salient features, future directions, and potential of GO membrane for separation fields using characterization techniques and gas separation test (studied gases are CO₂, He and N2), which is an efficient tool for better understanding of GO membrane behavior. GO membrane structure was examined over a wide range of parameters, such as pore size range of substrate and its surface properties, pH of GO dispersion, GO content, synthesis pressure, operating pressure and temperature. The results show that the GO content does not hold a linear relationship with the permeance and selectivity. Film thickness, aggregates, synthesis pressure defects and interlayer spacing have significant effects on the gas separation performance of GO membranes which originate from the synthesis method and its conditions.     

An Asymmetric Nanoscale SOI MOSFET by Means of a P-N Structure as Virtual Hole’s Well at the Source Side

Silicon - This paper suggests and investigates a p-n structure, which emulates as a MOSFET. In the proposed structure we utilize an L-shape contact with a proper work function over the source...