Fabrication and Optimization of Nafion as a Protective Membrane for TiN-Based pH Sensors.

In this study, a solid-state modified pH sensor with RF magnetron sputtering technology was developed. The sensor consists of an active electrode consisting of a titanium nitride (TiN) film with a protective membrane of Nafion and a reference glass electrode of Ag/AgCl. The sensitivity of the pH sensor was investigated.

Nafion Modified Titanium Nitride pH Sensor for Future Biomedical Applications.

pH sensors are increasingly being utilized in the biomedical field and have been implicated in health applications that aim to improve the monitoring and treatment of patients. In this work, a previously developed Titanium Nitride (TiN) solid-state pH sensor is further enhanced, with the potential to be used for pH regulation inside the human body and for other biomedical, industrial, and environmental applications. One of the main limitations of existing solid-state pH sensors is their reduced performance in high redox mediums.

LED Illumination for High-Quality High-Yield Crop Growth in Protected Cropping Environments.

Vegetables and herbs play a central role in the human diet due to their low fat and calory content and essential antioxidant, phytochemicals, and fiber. It is well known that the manipulation of light wavelengths illuminating the crops can enhance their growth rate and nutrient contents. To date, it has not been easy to generalize the effects of LED illumination because of the differences in the plant species investigated, the measured traits, the way wavelengths have been manipulated, and the plants' growing environments.

Sensing of Surface and Bulk Refractive Index Using Magnetophotonic Crystal with Hybrid Magneto-Optical Response.

We propose an all-dielectric magneto-photonic crystal with a hybrid magneto-optical response that allows for the simultaneous measurements of the surface and bulk refractive index of the analyzed substance. The approach is based on two different spectral features of the magneto-optical response corresponding to the resonances in p- and s-polarizations of the incident light. Angular spectra of p-polarized light have a step-like behavior near the total internal reflection angle which position is sensitive to the bulk refractive index.

Indoor optical wireless communication system with continuous and simultaneous positioning.

The optical wireless communication (OWC) technology has been widely studied to provide high-speed communications in indoor environments. The indoor OWC-based positioning function is also highly demanded and the received signal strength (RSS) method has attracted intensive interests, where multiple transmitters are used and the positioning information is provided by estimating the channel gain from each transmitter with known location. However, this process normally requires dedicated positioning time slots, RF carriers or codewords, which limit the system data rate and throughput.

LED Illumination Spectrum Manipulation for Increasing the Yield of Sweet Basil ( L.).

Manipulation of the LED illumination spectrum can enhance plant growth rate and development in grow tents. We report on the identification of the illumination spectrum required to significantly enhance the growth rate of sweet basil ( L.) plants in grow tent environments by controlling the LED wavebands illuminating the plants.

Titanium Nitride Thin Film Based Low-Redox-Interference Potentiometric pH Sensing Electrodes.

In this work, a solid-state potentiometric pH sensor is designed by incorporating a thin film of Radio Frequency Magnetron Sputtered (RFMS) Titanium Nitride (TiN) working electrode and a commercial Ag|AgCl|KCl double junction reference electrode. The sensor shows a linear pH slope of -59.1 mV/pH, R = 0.

Advanced fully integrated radiofrequency/optical-coherence-tomography irrigated catheter for atrial fibrillation ablation.

The inability of current catheter ablation procedures to accurately monitor lesion formation limits their safety and efficacy. An advanced fully integrated radiofrequency (RF)/optical coherence tomography (OCT) ablation catheter is developed, which enables real-time monitoring during ablation. An OCT fiber array is especially designed, developed and integrated into an off-the-shelf irrigated RF ablation catheter.

Outdoor phycocyanin production in a standalone thermally-insulated photobioreactor.

The operation of solar microalgal photobioreactors requires sufficient cooling and heating to maintain reliable high productivity year-round. These operations are energy-intensive and expensive. Growth characteristics and phycocyanin production of Arthrospira platensis were investigated during the austral winter using a thermally-insulated photobioreactor with photovoltaic panel integration for electricity generation.

Performances of the LBP Based Algorithm over CNN Models for Detecting Crops and Weeds with Similar Morphologies.

Weed invasions pose a threat to agricultural productivity. Weed recognition and detection play an important role in controlling weeds. The challenging problem of weed detection is how to discriminate between crops and weeds with a similar morphology under natural field conditions such as occlusion, varying lighting conditions, and different growth stages.

A novel method for detecting morphologically similar crops and weeds based on the combination of contour masks and filtered Local Binary Pattern operators.

Background: Weeds are a major cause of low agricultural productivity. Some weeds have morphological features similar to crops, making them difficult to discriminate.

Results: We propose a novel method using a combination of filtered features extracted by combined Local Binary Pattern operators and features extracted by plant-leaf contour masks to improve the discrimination rate between broadleaf plants.

Application-Specific Oxide-Based and Metal-Dielectric Thin-Film Materials Prepared by Radio Frequency Magnetron Sputtering.

We report on the development of several different thin-film functional material systems prepared by radio frequency (RF) magnetron sputtering at Edith Cowan University nanofabrication labs. While focusing on the RF sputtering process optimizations for new or the previously underexplored material compositions and multilayer structures, we disclose several unforeseen material properties and behaviours. Among these are an unconventional magnetic hysteresis loop with an intermediate saturation state observed in garnet trilayers, and an ultrasensitive magnetic switching behaviour in garnet-oxide composites (GOC).

High-speed indoor optical wireless communication system employing a silicon integrated photonic circuit.

Beam-steering-based optical wireless technologies are being widely investigated due to the capability of providing high-speed wireless connectivity in indoor applications. However, high-speed indoor optical wireless systems are traditionally realized with discrete bulky components, significantly limiting their practical applications. In this Letter, we demonstrate an infrared optical wireless communication system employing a miniaturized silicon integrated photonic circuit for beam steering for the first time.

Properties of Ferrite Garnet (Bi, Lu, Y)₃(Fe, Ga)₅O Thin Film Materials Prepared by RF Magnetron Sputtering.

This work is devoted to physical vapor deposition synthesis, and characterisation of bismuth and lutetium-substituted ferrite-garnet thin-film materials for magneto-optic (MO) applications. The properties of garnet thin films sputtered using a target of nominal composition type BiLuYFeGa₁O are studied. By measuring the optical transmission spectra at room temperature, the optical constants and the accurate film thicknesses can be evaluated using Swanepoel's envelope method.

Indoor infrared optical wireless localization system with background light power estimation capability.

The indoor user localization function is in high demand for high-speed wireless communications, navigations and smart-home applications. The optical wireless technology has been used to localize end users in indoor environments. However, its accuracy is typically very limited, due to the ambient light, which is relatively strong.

RuO₂ pH Sensor with Super-Glue-Inspired Reference Electrode.

A pH-sensitive RuO₂ electrode coated in a commercial cyanoacrylate adhesive typically exhibits very low pH sensitivity, and could be paired with a RuO₂ working electrode as a differential type pH sensor. However, such sensors display poor performance in real sample matrices. A pH sensor employing a RuO₂ pH-sensitive working electrode and a SiO₂-PVB junction-modified RuO₂ reference electrode is developed as an alternative high-performance solution.

Photonic microstructures for energy-generating clear glass and net-zero energy buildings.

Transparent energy-harvesting windows are emerging as practical building-integrated photovoltaics (BIPV), capable of generating electricity while simultaneously reducing heating and cooling demands. By incorporating spectrally-selective diffraction gratings as light deflecting structures of high visible transparency into lamination interlayers and using improved spectrally-selective thin-film coatings, most of the visible solar radiation can be transmitted through the glass windows with minimum attenuation. At the same time, the ultraviolet (UV) and a part of incident solar infrared (IR) radiation energy are converted and/or deflected geometrically towards the panel edge for collection by CuInSe2 solar cells.

Transverse magnetic field impact on waveguide modes of photonic crystals.

This Letter presents a theoretical and experimental study of waveguide modes of one-dimensional magneto-photonic crystals magnetized in the in-plane direction. It is shown that the propagation constants of the TM waveguide modes are sensitive to the transverse magnetization and the spectrum of the transverse magneto-optical Kerr effect has resonant features at mode excitation frequencies. Two types of structures are considered: a non-magnetic photonic crystal with an additional magnetic layer on top and a magneto-photonic crystal with a magnetic layer within each period.

Effect of vertically aligned carbon nanotube density on the water flux and salt rejection in desalination membranes.

In this paper, vertically aligned carbon nanotube (VACNT) membranes of different densities are developed and their performances are investigated. VACNT arrays of densities 5 × 10(9), 10(10), 5 × 10(10) and 10(11) tubes cm(-2), are initially grown on 1 cm × 1 cm silicon substrates using chemical vapour deposition. A VACNT membrane is realised by attaching a 300 μm-thick 1 cm × 1 cm VACNT array on silicon to a 4″ glass substrate, applying polydimethylsiloxane (PDMS) through spin coating to fill the gaps between the VACNTs, and using a microtome to slice the VACNT-PDMS composite into 25-μm-thick membranes.

Accurate modeling and positioning of a magnetically controlled catheter tip.

Purpose: This paper represents the initial phase of a proposed operator-friendly semiautomatic method for positioning and directing an intravascular three-magnet tip catheter in the human heart using an electromagnetic system.

Methods: A predictive computer algorithm based on a comprehensive mathematical model is developed, which accurately calculates the magnetic field generated by the electromagnet system as well as the magnetic torques and forces exerted on a three-magnet tip catheter, and generates the necessary electromagnet currents for arbitrary displacement and deflection of the catheter tip within a workspace of 128 × 128 × 128 mm.

Results: We demonstrate the ability of the developed mathematical model to accurately position a three-magnet tip catheter within the 128 × 128 × 128 mm workspace of a 3D eight-electromagnet system.

Laser from Optically Pumped Quantum Dot CdSe/ZnS in a Colloidal Liquid.

In this study, we had investigated the amplified spontaneous emission (ASE) characteristics of CdSe/ZnS quantum dot (QDs) in a colloidal liquid. A third harmonic of Nd:YAG laser (355 nm) was used to produce laser-induced fluorescence (LIF) at 605 nm with a spectral width of 0 nm [full width at half maximum (FWHM)]. When the pump power and focusing were carefully optimized, an ASE at 610 nm with a spectral width of Δλ = 8 nm (FWHM) could be obtained.

Sustainable cultivation of microalgae by an insulated glazed glass plate photobioreactor.

Microalgae growth in closed photobioreactors is greatly inhibited by elevated temperatures caused mainly by the infra-red portion of light. Current passive evaporative cooling systems for temperature control in outdoor photobioreactors are neither economical nor sustainable. Here we built a novel flat plate photobioreactor with its illumination surface customized with insulated glazing units (IGP).

Demonstration of multi-wavelength tunable fiber lasers based on a digital micromirror device processor.

Based on a digital micromirror device (DMD) processor as the multi-wavelength narrow-band tunable filter, we demonstrate a multi-port tunable fiber laser through experiments. The key property of this laser is that any lasing wavelength channel from any arbitrary output port can be switched independently over the whole C-band, which is only driven by single DMD chip flexibly. All outputs display an excellent tuning capacity and high consistency in the whole C-band with a 0.

Properties of Exchange Coupled All-garnet Magneto-Optic Thin Film Multilayer Structures.

The effects of exchange coupling on magnetic switching properties of all-garnet multilayer thin film structures are investigated. All-garnet structures are fabricated by sandwiching a magneto-soft material of composition type BiLuFeAlO or Bi₃Fe₅O:Dy₂O₃ in between two magneto-hard garnet material layers of composition type Bi₂Dy₁Fe₄Ga₁O or Bi₂Dy₁Fe₄Ga₁O:Bi₂O₃. The fabricated RF magnetron sputtered exchange-coupled all-garnet multilayers demonstrate a very attractive combination of magnetic properties, and are of interest for emerging applications in optical sensors and isolators, ultrafast nanophotonics and magneto-plasmonics.

Experimental demonstration of free-space based 120 Gb/s reconfigurable card-to-card optical interconnects.

In this Letter, we propose and experimentally demonstrate a free-space based reconfigurable card-to-card optical interconnect architecture with 16-carrierless-amplitude-phase modulation. Experimental results show that up to 120 Gb/s (3×40  Gb/s) flexible interconnection can be achieved for up to 30 cm distance with a worst-case receiver sensitivity of -9.70  dBm.