Power Equations and Capacity Performance of Magnetic Induction Communication Systems

Although a number of studies have been done on the traditional Radio Frequency (RF)terrestrial communication system, the potential applications and the advantages of Near-Field magnetically coupled coils in wireless short range communications is just emerging and is yet to be explored. This paper investigates the impacts of magnetically coupled transceiver antenna coil on the received signal power and the communication link capacity. Based on the equivalent circuit model in free space, theoretical foundations are laid with observed simulation results. The simulation result benefits the antenna designers and the network planning engineers to estimate the power at the receiver and a near field magnetic communication system capacity for different antenna coil characteristics and different communication ranges.     

A novel control scheme for simultaneous elimination of imbalance,disturbance and voltage harmonic in power systems

In recent years, the increasing application of nonlinear and unbalanced electronic equipment and large single phase loads have made voltage imbalance a serious problem in power distribution systems. A novel approach has been proposed to eliminate voltage imbalance and disturbances. The main strategy of this scheme is based on series active filter. By improving control circuit toward existing schemes and proposing a new strategy to control the voltage amplitude, simultaneous elimination of voltage imbalance, faults, voltage harmonics and also compensation of voltage drop in transmission lines become possible. Eventually, the voltage on the load side is a perfectly balanced three phase voltage with specific proper amplitude. The proposed scheme has been simulated in a test network and the results show high capability of this scheme for the complete elimination of imbalance without phase shift.     

RAARPL: End-to-end Reliability-Aware Adaptive RPL routing protocol for Internet of things

The RPL protocol has been accepted by the Internet Engineering Task Force as the only routing standard for the Internet of things (IoT). Although RPL has been significantly used in IoT routing, it still has extensive challenges. One of the most basic challenges is related to the reliability of routing. The severe limitations of resources, wireless communication, and variable topology, along with other limitations of IoT, have caused reliability in these networks to be a challenging topic. However, in RPL, no measures are provided to support the reliability of routing. To improve this issue, in this article, RPL was improved based on reliability requirements, and a new protocol was proposed called the Reliability-Aware Adaptive RPL routing protocol (RAARPL). RAARPL selects the parents based on the evaluation of various criteria related to reliability and forms the network topology. In addition, the conditions of the paths were also considered in the decision-making so that the reliability depends on the paths and parents. In order to maintain stability, RAARPL had controlled the parent selection and children assignment in a way that will prevent errors as much as possible. The simulation results by Cooja and compared with CLRPL and RPL protocols in various scenarios indicated the high efficiency of RAARPL in improving the reliability of data exchange and successful delivery ratio, reducing the instability of topology and the network throughput.     

Preliminary assessment of imidazolium-based room-temperature ionic liquids for extraction of organic contaminants from soils

Alternative solvents known as room-temperature ionic liquids (RTILs) were considered for extraction of organic soil contaminants. A hydrophobic RTIL, 1-butyl-3-methyl imidazolium hexafluorophosphate ([bmim]PF6), and a hydrophilic RTIL, 1-butyl-3-methyl imidazolium chloride ([bmim]Cl), were selected as representative imidazolium-based RTILs to assess the extraction of several organic contaminants (OCs) from two model soils. The two soils were montmorillonite (clay minerals, high surface area, and no organic matter) and glacial till (organic matter). The soils were spiked separately with DDT, dieldrin, hexachlorobenzene, and pentachlorophenol. With the exception of DDT, extractions of OCs from montmorillonite using [bmim]PF6 (79-92%) were nearly as effective as extractions with acetone and ethanol (85-100%). The extraction of OCs from glacial till with RTILs (15-61%) was less effective than extraction with organic solvents (59-100%). The [bmim]Cl was as efficient as [bmim]PF6 for extraction of OCs from glacial till, while [bmim]PF6 was more efficient than [bmim]Cl for extraction of OCs from montmorillonite. The two RTILs were most effective for the extraction of dieldrin (the heaviest OC) from both soils. The extraction results for glacial till showed dependence of OC extraction on the viscosity and melting point of RTILs.     

Chemical structure of sulfated polysaccharides from brown seaweed (Turbinaria turbinata)

The chemical structure of three sulfated polysaccharides fractions (TtF1, TtF2, and TtF3) obtained from anion-exchange separation of aqueous extracts of brown seaweed (Turbinaria turbinate) were studied. The infrared spectra patterns showed that the fractions possess functional groups similar to that of sulfated polysaccharides. The sulfated polysaccharides fractions exhibited molecular weights of 223.5, 495.5, and 326.05 kDa, respectively, for TtF1, TtF2, and TtF3. ¹H NMR spectra of TtF2 and TtF3 contain α-anomeric protons (5–5.6 ppm), ring protons (3.4–4.4), and methyl protons (1–1.3 ppm) while that of TtF1 only exhibited ring protons and methyl protons. Rheological data were fitted to power law which revealed that the fractions were Newtonian and/or presented weak pseudoplastic behavior. Consistency values increased with concentration in all fractions. Consistency values of TtF2 were the highest, followed by TtF1 and then TtF3. Thermal degradation patterns of TtF1 and TtF2 were similar but different from that of TtF3. This study confirmed that chemical and physical characteristics of sulfated polysaccharides fractions are interrelated and provided in-depth understanding of sulfated polysaccharides of brown algae.     

The cause, prevention, and treatment of recurrent groin hernia

At present, groin hernia repair is associated with a 10% recurrence rate. Despite innumerable modifications of the Bassini technique, this depressing figure remains essentially unimproved. This article documents the two major reasons for failure and presents techniques that are simple, can be performed under local anesthesia in an outpatient setting, allow patients to return home within hours of their surgery, encourage rapid return to unrestricted activity, and are associated with a recurrence rate approaching 0%.     

Structural,magnetic, and electrical properties of RFeO3 (R = Dy,Ho, Yb & Lu) compounds

Journal of Materials Science: Materials in Electronics - In this research, the nanosized rare-earth orthoferrites (RFeO3) with R?=?Dy, Ho, Yb & Lu were synthesized by...     

An Omniphobic Spray Coating Created from Hierarchical Structures Prevents the Contamination of High-Touch Surfaces with Pathogens

Engineered surfaces that repel pathogens are of great interest due to their role in mitigating the spread of infectious diseases. A robust, universal, and scalable omniphobic spray coating with excellent repellency against water, oil, and pathogens is presented. The coating is substrate-independent and relies on hierarchically structured polydimethylsiloxane (PDMS) microparticles, decorated with gold nanoparticles (AuNPs). Wettability studies reveal the relationship between surface texturing of micro- and/or nano-hierarchical structures and the omniphobicity of the coating. Studies of pathogen transfer with bacteria and viruses reveal that an uncoated contaminated glove transfers pathogens to >50 subsequent surfaces, while a coated glove picks up 10⁴ (over 99.99%) less pathogens upon first contact and transfers zero pathogens after the second touch. The developed coating also provides excellent stability under harsh conditions. The remarkable anti-pathogen properties of this surface combined with its ease of implementation, substantiate its use for the prevention of surface-mediated transmission of pathogens.