Trends of deposition and patterning techniques of TiO2 for memristor based bio-sensing applications

Memristor is a new element that has potential in various fields such as memory, neural network, FPGA, computing and bio-sensing. Among listed, research on memristor in bio-sensing applications is very minimal. There are a lot of researches done in bio-sensing applications but they are not looking at the memristive behavior effect but most of them are looking at surface effect or cyclic voltammetry effect or amperometric response. This study will focused on memristive behavior of memristor sensor in bio-sensing applications. At first, this paper discusses brief overview about deposition techniques of TiO₂. In second part, the details overview of TiO₂ patterning techniques will be covered. There are four patterning techniques that can be used for TiO₂ patterning which are lift off techniques, sol–gel base imprint lithography techniques, etching techniques and site-selective deposition techniques. Third part discussed in general about bio-sensing applications including two researches on memristor sensor that has been done. At last, this paper will propose a design of memristor sensor using TiO₂ material to be used in bio-sensing applications. TiO₂ material was chosen as the sensing material due to its wide used in sensing applications including gas sensing, bio-sensing and humidity sensing. TiO₂ is also the best material that has the best memristive behavior beside Si, ZnO and others.     

Application of magnetic polyaniline nanocomposite for separation of uranyl ions from aqueous solutions

Polyaniline (PANI) was synthesized chemically, and then modified with magnetic iron oxide nanoparticles (Fe₃O₄ NPs). PANI and PANI-Fe₃O₄ NPs were used for removal of uranyl ions (UO₂²⁺) from aqueous solutions using a batch system. The synthesized adsorbents were characterized using FT-IR, SEM, BET and XRD techniques. From isotherm investigation, the maximum adsorption capacities (q_m) were 150.0 and 108.0 mg g^?1 for PANI and PANI-Fe₃O₄NPs, respectively. The kinetics and equilibrium adsorptions were well-described by the pseudo-second-order kinetic and Langmuir model, respectively. Thermodynamic studies depicted that the adsorption of uranyl ions by PANI is a spontaneous exothermic process and in the case of PANI-Fe₃O₄ NPs, adsorption process is endothermic; therefore, the spontaneity is controlled by entropy.     

Transmission-line matrix method for solving the multidimensional continuity equation

We have extended the one-dimensional transmission-line modelling (TLM) of diffusion, drift and recombination of charge carriers in semiconductors to multiple dimensions. Detailed TLM formulation of the continuity transport equation in a more general form is presented.     

Toxicological assessment of 3-monochloropropane-1,2-diol (3-MCPD) as a main contaminant of foodstuff in three different in vitro models: Involvement of oxidative stress and cell death signaling pathway

3-Monochloropropane-1,2-diol (3-MCPD) as a main source of food contamination has always been known as a carcinogenic agent. Kidney, liver, testis, and heart seem to be the main target organs for 3-MCPD. Because oxidative stress and mitochondrial dysfunction have been realized to be involved in 3-MCPD-induced cytotoxicity, the present study aimed to investigate the probable toxicity mechanisms of 3-MCPD in isolated mitochondria, HEK-293 cell line, and cell isolated from the rats’ liver and kidney through measuring multiparametric oxidative stress assay. Based on the data indicating no significant difference between 3-MCPD-treated groups and control group, metabolites of 3-MCPD have a key role in organ toxicity caused by them. To further investigating the suggested hypothesis, the effect of 3-MCPD toxicity on HEK-293 cell line was examined. Although the proliferation declined after exposure to a low dose of 3-MCPD (10 to 200 µM), controversial responses in higher concentration (2 to 10 mM) have led to studies on the effect of oxidative stress and cell death signaling on isolated kidney and liver cells. Treatment of the isolated kidney and liver cells with 3-MCPD resulted in an increase in the level of reactive oxygen species (ROS), the collapse of mitochondrial membrane potential (MMP), and activation of cell death signaling without creating any significant difference in the amount of reduced glutathione. In fact, 3-MCPD can disrupt the mitochondrial electron transfer in isolated cells, which is correlated with the impairment of mitochondrial oxidative phosphorylation system, the rise of ROS level, and the failure of MMP, leading to the release of cytochrome c from mitochondria to cytosol and finally the activation of cell death signaling.     

A novel one-pot biosynthesis of pure alpha aluminum oxide nanoparticles using the macroalgae Sargassum ilicifolium: A green marine approach

A novel biological method is proposed for producing ceramic alpha aluminum oxide nanoparticles using an extract of the algae Sargassum ilicifolium. The algal extract functions as a bioreducing as well as a stabilizer agent. The presence of an absorption peak at 227?nm, confirmed the formation of the aluminum oxide nanoparticles using a UV–visible spectroscopy. FTIR analysis indicated that bioreduction of aluminum ions and nanoparticle stabilization probably occurred by interactions between aluminum and the biofunctional groups of algal extract. The XRD pattern revealed that after calcination at ~ 1200?°C, the Al₂O₃ nanoparticles were alpha crystalline in nature with a diameter of 35?nm and had a rhombohedral structure. TEM indicated that the alumina nanoparticles were well-dispersed and spherical in shape with an average size of 20?±?2.1?nm. EDX spectroscopy revealed that the sample contained only aluminum (46.31%) and oxygen (53.69%), confirming the high purity of the alumina nanopowder. The results demonstrated that alpha alumina NPs has an optical band gap of 5.46?eV.     

Characteristics of Si3N4/GaAs metal-lnsulator-semiconductor interfaces with coherent Si/Al0.3Ga0.7As interlayers

Si₃N₄/GaAs metal-insulator-semiconductor (MIS) interfaces with Si(10Å)/ Al_0.3Ga_0.7As (20Å) interface control layers have been characterized using capacitance-voltage (C-V) and conductance methods. The structure was in situ grown by a combination of molecular beam epitaxy and chemical vapor deposition. A density of interface states in the 1.1 × 10¹¹ eV^-1 cm^-2 range near the GaAs midgap as determined by the conductance loss has been attained with an ex situ solid phase annealing of 600°C in N₂ ambient. A dip quasi-static C-V demonstrating the inversion of the minority-carrier verifies the decent interface quality of GaAs MIS interface. The hysteresis and frequency dispersion of the MIS capacitors were lower than 100 mV, some of them as low as 50 mV under a field swing of about ±2 MV/cm. The increase of the conductance loss at higher frequencies was observed when employing the surface potential toward conduction band edge, suggesting the dominance of faster traps. Self-aligned gate depletion mode GaAs metal-insulator-semiconductor field-effect transistors with Si/Al_0.3Ga_0.7As interlayers having 3 μm gate lengths exhibited a transconductance of about 114 mS/mm. The present article reports the first application of pseudomorphic Si/ Al_0.3Ga_0.7As interlayers to ideal GaAs MIS devices and demonstrates a favorable interface stability.     

Host choice by indoor-resting Anopheles arabiensis in Ethiopia

The host preference of indoor resting Anopheles arabiensis has been determined using a direct enzyme-linked immunosorbent assay. A total of 611 specimens, 258 from human dwellings, 179 from mixed dwellings, and 174 from cattle sheds, was examined. The proportion of human blood meals identified was highest from mosquitoes caught in human dwellings (91.5%), followed by those from mixed dwellings (20.2%) and cattle sheds (3.5%) (P < 0.0001). The smaller proportion of human blood meals from mixed dwellings suggests that cattle may protect humans from A. arabiensis.     

Medical image segmentation using customized U-Net with adaptive activation functions

Neural Computing and Applications - Since medical imaging is a fundamental step in clinical diagnosis and treatment, medical image processing is an attractive field for researchers. Among the...     

Feedback stabilization of discrete-time quantum systems subject to non-demolition measurements with imperfections and delays

We consider a controlled quantum system whose finite dimensional state is governed by a discrete-time nonlinear Markov process. In open-loop, the measurements are assumed to be quantum non-demolition (QND). The eigenstates of the measured observable are thus the open-loop stationary states: they are used to construct a closed-loop supermartingale playing the role of a strict control Lyapunov function. The parameters of this supermartingale are calculated by inverting a Metzler matrix that characterizes the impact of the control input on the Kraus operators defining the Markov process. The resulting state feedback scheme, taking into account a known constant delay, provides the almost sure convergence to the target state. This convergence is ensured even in the case where the filter equation results from imperfect measurements corrupted by random errors with conditional probabilities given as a left stochastic matrix. Closed-loop simulations corroborated by experimental data illustrate the interest of such nonlinear feedback scheme for the photon box, a cavity quantum electrodynamics system.     

Desulfurization of high sulfur petroleum coke by molten caustic leaching

Desulfurization by molten caustic leaching (MCL) at 400–500 °C has been investigated in order to reduce the sulfur content of petroleum coke. Effective parameters on desulfurization of petroleum coke, other than temperature, include alkali to feed (petroleum coke) mass ratio, time and mesh size in the ranges of 0.5–1.5, 1–3 h and 200–600 µm, respectively. In this work, petroleum coke desulfurization conditions using solid KOH have been studied. Maximum petroleum coke desulfurization by MCL method has been obtained by Taguchi L9 design using alkali to feed mass ratio of 1, temperature of 600 °C, time of 2 h and mesh size of 200 µm. The changes in the main groups on the coke surface have been determined using FTIR spectroscopy. In addition, SEM-EDX, TGA and XRD analyses have been used to investigate the changes in coke physical and chemical properties.