Hexagonal Type Ising Nanowire with Spin-1 Core and Spin-2 Shell Structure

Thermodynamic properties and phase diagrams of a mixed spin-(1,2) Ising ferrimagnetic system with single ion anisotropy on hexagonal nanowire are studied by using effective-field theory with correlations. The susceptibility, internal energy and specific heat of the system are numerically examined and some interesting phenomena in these quantities are found. The effect of the Hamiltonian parameters on phase diagrams are examined in detail. Besides second-order phase transition, lines of first-order transition and tricritical points are found. In particular, we found that for some negative values of single-ion anisotropies, there exist first-order phase transitions.     

Numerical investigation of BB-AMR scheme using entropy production as refinement criterion

In this work, a parallel finite volume scheme on unstructured meshes is applied to fluid flow for multidimensional hyperbolic system of conservation laws. It is based on a block-based adaptive mesh refinement strategy which allows quick meshing and easy parallelisation. As a continuation and as an extension of a previous work, the useful numerical density of entropy production is used as mesh refinement criterion combined with a local time-stepping method to preserve the computational time. Then, we numerically investigate its efficiency through several test cases with a confrontation with exact solution or experimental data.     

Complexiton solutions for two nonlinear partial differential equations via modification of simplified Hirota method

In this study, we obtain complexiton solutions of Sawada–Kotera equation and ninth-order KdV equation. For this cause, we employ Wazwaz and Zhaqilao’s method which can be regarded as generalization of simplified Hirota method through extension real parameters into complex parameters. Special conditions to distinguish complexiton, soliton, and soliton–complexiton interaction solutions from each other are given.     

Brain Inspired Cortical Coding Method for Fast Clustering and Codebook Generation

Highlights What are the main findings?

• A cortical coding method is developed inspired by the network formation in the brain, where the information entropy is maximized while dissipated energy is minimized.
• The execution time in the cortical coding model is far superior, seconds versus minutes or hours, compared to those of the frequently used current algorithms, while retaining comparable distortion rate.

What is the implication of the main finding?

• The significant attribute of the methodology is its generalization performance, i.e., learning rather than memorizing data.
• Although only vector quantization property was demonstrated herein, the cortical coding algorithm has a real potential in a wide variety of real-time machine learning implementations such as , temporal clustering, data compression, audio and video encoding, anomaly detection, and recognition, to list a few.

AbstractA major archetype of artificial intelligence is developing algorithms facilitating temporal efficiency and accuracy while boosting the generalization performance. Even with the latest developments in machine learning, a key limitation has been the inefficient feature extraction from the initial data, which is essential in performance optimization. Here, we introduce a feature extraction method inspired by energy–entropy relations of sensory cortical networks in the brain. Dubbed the brain-inspired cortex, the algorithm provides convergence to orthogonal features from streaming signals with superior computational efficiency while processing data in a compressed form. We demonstrate the performance of the new algorithm using artificially created complex data by comparing it with the commonly used traditional clustering algorithms, such as Birch, GMM, and K-means. While the data processing time is significantly reduced—seconds versus hours—encoding distortions remain essentially the same in the new algorithm, providing a basis for better generalization. Although we show herein the superior performance of the cortical coding model in clustering and vector quantization, it also provides potent implementation opportunities for machine learning fundamental components, such as reasoning, anomaly detection and classification in large scope applications, e.g., finance, cybersecurity, and healthcare.     

Measurement of the Antipsychotic Clozapine Using Reduced Graphene Oxide Nanocomposites-Au/Pd/Pt Electrodes

Enhanced methods of drug monitoring are required to support the individualization of therapeutic drug dosing. Clozapine is one of the most important medications for managing schizophrenia, and timely measurement of serum clozapine levels has been identified as a barrier to the broader use of clozapine. For the first time, reduced graphene oxide nanocomposites were used to construct an electrochemical clozapine (Clz) sensor. The Reduced graphene oxide (Rego) nanocomposites were synthesized and characterized by using X-Ray Diffraction (XRD), Fourier-Transform Infrared Spectroscopy (FTIR), Scanning Electron Microscopy (SEM), and Transmission Electron Microscopy (TEM) techniques. The Clz sensing electrode was fabricated by drop coating of Rego nanocomposites suspension and Nafion solution on the pencil graphite electrode, respectively. The electrochemical behavior and influence of various physicochemical parameters of sensing electrodes were investigated by using cyclic voltammetry (CV) and differential voltammetry (DPV) techniques. The designed sensor displayed decent linear range, detection limit, reproducibility, and reusability results. Under optimum experimental parameters a linear dynamic range of 0.05–10 μM clozapine was observed with actual detection limit of 50 nM. Furthermore, the designed sensing electrode was used to measure the amount of Clz in real samples.     

Synthesis and X-ray crystal structure determination of N-p-methylphenyl-4-benzoyl-3,4-diphenyl-2-azetidinone

The title compound, C₂₉H₂₃NO₂, has been characterized by single-crystal X-ray diffraction at two different temperatures (303 K and 120 K) and wavelengths (MoK _α and CuK _α). The non-centrosymmetric hexagonal crystal structure contains four-membered planar β-lactam ring with an unusually long C-C bond. The β-lactam ring is almost planar.     

Preparation and characterization of a novel activated carbon component via chemical activation of tea woody stem

Journal of Thermal Analysis and Calorimetry - The novel activated carbon materials were synthesized by the carbonization and chemical activation of agricultural bio-waste from tea woody stems...     

Visible light-induced synthesis of polysulfone-based graft copolymers by a grafting from approach

The synthesis of polysulfone (PSU) graft copolymers by a two-step “grafting from” approach is described. First, a chlorofunctional PSU (PSU-Cl) is formed via chloromethylation of a commercial PSU. The formed polymers are used macroinitiator for the dimanganese decacarbonyl assisted free-radical polymerization of tert-butyl acrylate, methyl methacrylate, and styrene to give the desired graft copolymers. Moreover, amphiphilic graft copolymers are also formed via posthydrolyzation of poly(tert-butyl acrylate) containing graft copolymers. The intermediates at various stages and the ultimate graft copolymers are characterized by various analysis techniques. © 2020 Wiley Periodicals, Inc. J. Polym. Sci. 2020 , 58, 412–416     

Performance Assessment of a Perfluorosulfonic Acid‐type Membrane (i. e. Nafion™ 115) for an Enzymatic Fuel Cell

A high power enzymatic fuel‐cell was anticipated by using a recently developed glucose oxidase (GOx) immobilized bio‐anode, a conventional platinum?carbon based cathode and a popular high performance 125 μ‐thick perfluorosulfonic acid‐type proton exchange membrane (i. e. Nafion® 115). Unexpected current density decay from 2.13 mA cm^?2 to 0.28 mA cm^?2 was observed within 2 hours. Polarization measurements and AC impedance analysis indicated that loss of performance was linked to the membrane behavior. Ion exchange between buffer solution and membrane was perceived as the main cause for the fast performance loss. Saturation of the membrane with the cation in the buffer solution diminished proton transfer needed for cathode reaction. Charge transfer resistances, obtained from AC impedance data, increased with time substantially due to cation exchange within membrane. Replacement of membrane with the same enzyme electrode and cathode has resulted 100 % current density recovery on the fuel cell performance. It was concluded that a membrane, not affected by the buffer cations, was required for successful enzymatic fuel cell applications.     

Synthesis and antiproliferative evaluation of novel biheterocycles based on coumarin and 2-aminoselenophene-3-carbonitrile unit

Monatshefte für Chemie - Chemical Monthly - A series of novel coumarins with 2-amino-3-cyanoselenophen-5-yl unit on C-3 have been synthesized. These compounds prepared easily at room...