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Field coupling via capacitor, inductor, or memristor has been applied for synchronization and consensus between nonlinear circuits and neural systems. The initial-condition-controlled synchronization behaviors therein are attractive to chaos-based applications and have not been intensively explored. In this paper, inductor coupling is applied between two memristive Chua's circuits to investigate the synchronization behaviors controlled by the coupling inductor and the initial conditions of each coupled terminals. Based on the dimensionless model, the error functions and similarity indexes for memristive and non-memristive variables are calculated to evaluate the synchronicity of the inductively coupled system. The results show that complete, lag, and parallel-offset synchronization behaviors can be realized by selecting different inductance and initial condition values for the coupling inductor. Moreover, the synchronization behaviors can be flexibly tuned from two coupled terminals by adjusting their initial conditions. Experimental verifications are finally performed using FPGA-based digital platform. This synchronization scheme and feature may promote the implementations of chaos-based applications for multi-stable dynamical systems. [ABSTRACT FROM AUTHOR]

Non-equilibrium inductively coupled plasmas (ICPs) operating in hydrogen are of significant interest for applications including large-area materials processing. Increasing control of spatial gas heating, which drives the formation of neutral species density gradients and the rate of gas-temperature-dependent reactions, is critical. In this study, we use 2D fluid-kinetic simulations with the Hybrid Plasma Equipment Model to investigate the spatially resolved production of atomic hydrogen in a low-pressure planar ICP operating in pure hydrogen (10–20 Pa or 0.075–0.15 Torr, 300 W). The reaction set incorporates self-consistent calculation of the spatially resolved gas temperature and 14 vibrationally excited states. We find that the formation of neutral-gas density gradients, which result from spatially non-uniform electrical power deposition at constant pressure, can drive significant variations in the vibrational distribution function and density of atomic hydrogen when gas heating is spatially resolved. This highlights the significance of spatial gas heating on the production of reactive species in relatively high-power-density plasma processing sources. [ABSTRACT FROM AUTHOR]

A differentially fed capsule antenna with a complex input impedance is proposed in this letter. The antenna maintains a circular flat shape with a diameter of 10 mm and operates at the desired band of the RF chip (2.4–2.525 GHz). With the utilization of an inductively coupled fed structure and dual meandered radiators, a –10 dB impedance bandwidth of 10.2% is achieved. In the meantime, the high impedance tunability can be realized by adjusting corresponding structural parameters. The operating mechanisms and parametric studies are explored in detail to investigate the characteristic of the proposed structure. The capsule antenna prototype is fabricated, assembled, and measured according to the practical scenario. The measured results highly agree with the simulation ones, which indicate that the proposed antenna could be a good candidate for wireless capsule endoscopy applications. [ABSTRACT FROM AUTHOR]

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A LIBS equipment operating at 532 nm was optimized and used for sulfur determination in concrete samples. The influence of He atmosphere in a gas-tight chamber (1000–200 mbar) on S I 921.29 nm line sensitivity, signal-to-background and signal-to-noise ratio was studied at gate delays 100–2000 ns. Wide range of gate delays from 500 to about 1000 ns and pressures from several hundreds of mbar to the atmospheric pressure can be used for the desired detection of sulfur. The LIBS quantification was done using a simple calibration method. A synthetic limestone enriched by defined amounts of sodium sulfate was newly employed for direct quantification of S in concrete. This powder material was pressed into pellets and ablated with the LIBS system. The average content of sulfur as SO 3 in the samples was 0.41–0.70 wt% by LIBS and 0.43–0.61 wt% by a reference standard procedure employing gravimetry and Inductively Coupled Plasma Triple Quad Mass Spectrometry (ICP-QQQMS). The uncertainty of the yielded LIBS results covers also the dispersion of the points in the calibration line and ranges from 16 to 28% at the probability level of 95%. The uncertainty of the ICP-QQQMS results was almost 10%. No correction on different signal response on the limestone and on the concrete was necessary. [ABSTRACT FROM AUTHOR]

This paper presents an approach for modeling and design of inductively coupled wireless bio-pressure sensor system for chronic intracardiac pressure monitoring. Making use of recent advances in microelectromechanical systems and semiconductor technology, bio-pressure sensor is developed as a series LC resonant circuit with a featured pressure-dependent capacitance working at the medical implant communication service band of 402–405 MHz for wireless sensing without power consumption. The microfabricated sensor consists of a planar spiral gold (Au) coil, a series capacitor, an SU-8-based frame structure, and an encapsulated bio-compatible PDMS membrane. Bio-pressure sensor is designed with a small footprint of 3.2 mm $\times $ 3.2 mm for reducing the bleeding and infection risks in surgery. With a limited footprint and desired working frequency, there are many mutually dependent geometry parameters with numerous combined groups of values involved in the full optimization of the system. In order to maximize the performance of system under the design requirements, RF characteristics that affect inductive sensitivity and pressure sensitivity are theoretically analyzed first, and then design of experiments method is applied to model and optimize 3-D electromagnetic models of sensor and sensor system on the derived RF characteristics. The large number of combined groups of values in factorial simulations is thus reduced to a few performance-related design factors. By monitoring the induced peak impedance of the readout coil, the pressure-dependent resonant frequency of the sensor can be detected and measured. The experimental results show that the optimized wireless sensor system has a relatively high average pressure sensitivity of 5.3 KHz/mm Hg at a telemetry distance of 10 mm demonstrating its potential for intracardiac pressure monitoring. [ABSTRACT FROM AUTHOR]

Use of raw seaweed for direct consumption and its extract in food production has increased steadily throughout the world. However the ability of metal sorption in seaweed may result in accumulation of some heavy metals which could be harmful to consumers. Tissue culture has been considered as an alternative method to produce uncontaminated seaweeds as seedlings for sustainable farming and raw materials for various industries including food production. In this study, Inductively Coupled Plasma Optical Emission Spectroscopy (ICP-OES) was used to determine the metal concentration in both field cultured and tissue cultured Kappaphycus alvarezii and Gracilaria changii. Results indicated that concentration of heavy metals with great scientific importance such as arsenic (As), cadmium (Cd) and lead (Pb) from tissue cultured samples has met the specific standard of health requirement from Joint FAO/WHO Expert Committee on Food Additive (JECFA) and Health Council and National Medicine Academy of France. Tissue cultured seaweeds also appeared to have lower As, Cd and Pb concentrations as compared to field cultured seaweeds. This may due to the stable and clean environment provided in tissue culture, contrasting with uncontrollable seasonal inflow of heavy metals in the field. [ABSTRACT FROM AUTHOR]

In this study, the impact of various deposition parameters such as the reactive gas flow ratio, plasma power, substrate temperature and chamber back pressure of ICP-CVD deposited a-SiC:H thin films is investigated and the influence on important MEMS-related properties like residual stress, Young’s modulus, hardness, mass density and refractive index is evaluated. Basically, tailoring of the as-deposited a-SiC:H characteristics is possible to a great extent with residual stress values ranging from −16 up to −808 MPa, Young’s modulus values between 36 and 209 GPa or deposition of layers with hardness values ranging from 5.3 to 27.2 GPa is feasible. Especially the mechanical parameters are strongly linked to both the Si C bond density and the amount of incorporated hydrogen obtained from Fourier transform infrared spectroscopy analyses. [ABSTRACT FROM AUTHOR]

There have been many different techniques to implement faster charging and increase the longevity of a battery. There are recent initiatives to design more robust methods and systems. In this paper, a new method is described to improve the speed of pulse-charge systems (PCS). There are two clock phases of periodic-charging in PCS; one clock phase is for charging and the other clock phase is for resting. In normal conditions, the charging phase uses the maximum current, which can adversely affect the reliability of a particular battery, if applied constantly. In this paper, it is shown that a small amount of charge can be used during resting phase to reduce the long charging time. [ABSTRACT FROM AUTHOR]

Amorphous hydrogenated carbon (a-C:H) deposited on steel with plasma enhanced chemical vapor deposition can be used as elongation tolerant oxygen barrier. However, the elongation tolerance of the a-C:H film is lost if deposited on a poly(ethylene terephthalate) (PET) for reasons unknown. To assess this phenomenon, a-C:H was deposited on PET, silicon substrates, and silicon micro-cantilevers, and the stress was determined by measuring the radius of curvature. a-C:H deposited on PET showed lower compressive stress than on silicon. This difference is not due to the formation of a gradient layer or plastic deformation of PET. Instead, the most probable explanation is that energetic ions cause a partial release of biaxial orientation within the PET, thereby reducing the compressive stress. [ABSTRACT FROM AUTHOR]

As an emerging research field, inductively coupled wireless power transfer (ICWPT) technology has attracted wide spread attention recently. In this paper, the maximum power transfer performances of four basic topologies labeled as SS, SP, PS and PP are investigated. By modeling the equivalent circuits of these topologies in high frequency (HF), the primary resonance compensation capacitances for maximum power transfer capability are deduced. It is found that these capacitances fluctuate with load resistance change, which is disadvantageous to SP, PS and PP topologies and an obstacle to their practical applications as well. To solve this problem, a phase controlled inductor circuit is proposed. By adjusting the triggering angle, the real-time dynamic tuning control can be achieved to guarantee maximum power transfer. Finally, simulations and experiments show that the proposed method is of great effectiveness and reliability to solve the issue of resonance compensation capacitance fluctuation with load change and to guarantee the flexible applications of all topologies. [ABSTRACT FROM AUTHOR]

For the first time, a commercial low pressure plasma sterilization system integrated in a pharmaceutical filling line is presented. The route from a laboratory plasma reactor to an industry scale plasma sterilization reactor is shown. Absolutely calibrated measurements (e.g. OES and Langmuir probe) yield to a knowledge transfer from an experimental set-up to an industrial reactor. Spore count reduction of 4 log in 10 s of Geobacillus stearothermophilus and Bacillus subtilis spores prove the applicability of an industrial grade plasma sterilization reactor for transfer isolators typically used in pharmaceutical filling and packaging lines. [ABSTRACT FROM AUTHOR]

Metal content of cotton is of increasing importance to cotton processors both because of effects on processing and product qualities and because of potential environmental concerns and constraints. Metals can contribute to problems that occur in yarn manufacturing, fabric production, bleaching and dyeing processes. Disposal of both liquid and solid wastes containing certain metals must be carefully monitored and controlled. Cottons varying in growth area, variety and harvest season were analyzed for potassium, magnesium, calcium, sodium, iron, copper, manganese, zinc, lead and cadmium contents by atomic absorption spectroscopy. Metal contents varied significantly between years and between growth areas. Potassium was the dominant metal (2000-6500 ppm) followed by magnesium and calcium (400-1200 ppm), sodium (100-300 ppm), iron (20-90 ppm) and zinc, manganese and copper (1-10 ppm). Lead and cadmium were not detectable in any of the cottons at test sensitivity limits of about one ppm. [ABSTRACT FROM AUTHOR]

Different preferential sites for etching are observed for low pressure argon and oxygen plasma on ultra-high molecular weight polyethylene. Atomic force microscopy analysis showed an organized pattern after 1 min of oxygen plasma treatment. Roughness decreases after 3 min and then after 5 min increases again, when surface is completely damaged. A different etching pattern is observed after argon plasma treatment, where nanometric pits are formed with size increasing with treatment time. Infrared spectroscopy shows that, by analyzing the relative intensity of the different peaks, the different etching mechanisms are explained where oxygen plasma reduces coupling between parallel chains in the crystalline short axis direction and argon plasma suppresses hydrogen and induces surface reorientation of functional groups. Image 1 • Different etching mechanisms were observed for oxygen and argon plasmas. • AFM results were corroborated by different relative intensities in FTIR. • Oxygen Plasma induced bond breaking in the short axis of the crystalline structure. • Argon plasma induced hole formation by breaking bonds in an aleatory way. [ABSTRACT FROM AUTHOR]

• Single crystal rutile can give 6 times the X-band EPR resonator efficiency of an LGR. • A factor of two higher saturable EPR signal for aqueous sample sizes near 400 nL. • Dielectric in the inner loop of an LGR can perform similarly to a DR. • Experimental results are compared with analytic theory and finite element simulations. • Polycrystalline rutile has background signals that make it unsuitable for EPR use. The performance of a metallic microwave resonator that contains a dielectric depends on the separation between metallic and dielectric surfaces, which affects radio frequency currents, evanescent waves, and polarization charges. The problem has previously been discussed for an X-band TE 011 cylindrical cavity resonator that contains an axial dielectric tube (Hyde and Mett, 2017). Here, a short rutile dielectric tube inserted into a loop-gap resonator (LGR) at X-band, which is called a dielectric LGR (dLGR), is considered. The theory is developed and experimental results are presented. It was found that a central sample loop surrounded by four "flux-return" loops (i.e., 5-loop–4-gap) is preferable to a 3-loop–2-gap configuration. For sufficiently small samples (less than 1 µL), a rutile dLGR is preferred relative to an LGR both at constant Λ (B 1 / P l ) and at constant incident power. Introduction of LGR technology to X-band EPR was a significant advance for site-directed spin labeling because of small sample size and high Λ. The rutile dLGR introduced in this work offers further extension to samples that can be as small as 50 nL when using typical EPR acquisition times. [ABSTRACT FROM AUTHOR]