Electrical and Dielectric Properties of Non-magnetic Al<Superscript>3+</Superscript> Substituted Ni–Zn Nano Ferrites for High Frequency Applications

The effect of Al substitution on electrical and dielectric parameters of Ni–Zn ferrite has been discussed in the present work. The phase identification, surface morphology was studied using X-ray diffractometer (XRD), scanning electron microscope (SEM), respectively. The XRD patterns confirm the single-phase formation of these ferrites. With Al³⁺, substitution lattice parameter decreases due to smaller Al³⁺ ions replacing Fe³⁺ ions. The average grain size obtained from SEM results are in the range of 390–27 nm. The DC resistivity was observed to increase with increasing Al³⁺ ions concentration due to the unavailability of Fe³⁺ ions. Dielectric constant (\(\upvarepsilon ^{\prime }\)) and dielectric loss tangent (tan δ) have been studied as a function of frequency (1 kHz–10 MHz) and temperature (50–300 °C). The observed results are explained on the basis of interfacial polarization as predicted by Maxwell and Wagner.     

Enantiospecific Synthesis and Cytotoxicity Evaluation of Oximidine II Analogues

Analogues of the anticancer natural product oximidine II were prepared and evaluated for cytotoxicity. One analogue of oximidine II that carries a C15 allylic amide side chain as well as two analogues with C15 vinyl sulfone side chains were found to lack cytotoxicity against the cancer cell line SK‐Mel‐5, thereby confirming the necessity of the C15 enamide side chain of oximidine II for cytotoxicity. Four analogues, designed by comparative molecular similarity index analysis (CoMSIA), that feature a less complex macrolactone scaffold were prepared and tested. The two analogues carrying a C15 vinyl sulfone group and the two analogues with a C15 oximidine II enamide side chain showed weak cytotoxicity against the SK‐Mel‐5 cell line and other cell lines, indicating that the designed simplified macrocycles cannot replace the oximidine II macrocycle.     

Synthesis of PEO-based di-block glycopolymers at various pendant spacer lengths of glucose moiety and their in-vitro biocompatibility with MC3T3 osteoblast cells

Di-block copolymers of poly(ethylene oxide) (PEO) and glycopolymers at three different pendant spacer lengths of glucose moiety were synthesized by deacetylation of pendant moieties of 2,3,4,6-tetra-O-acetyl-d-glucopyranosides which were prepared by reversible addition-fragmentation chain-transfer (RAFT) process. The water soluble deacetylated copolymers, PEO-b-poly(acryl-d-glucopyranoside) (PEO-b-PAG, 2a), PEO-b-poly[4′-(acryloxy)butyl-d-glucopyranoside] (PEO-b-PABG, 2b), and PEO-b-poly[6′-(acryloxy)hexyl-d-glucopyranoside] (PEO-b-PAHG, 2c) were characterized in comparison with acetylated copolymers by spectroscopic and gel permeation chromatography methods. In order to assess the biocompatibility of these three di-block copolymers, the adhesion (%), viability (%), and proliferation assays were carried out in MC3T3 cells in-vitro at different concentrations from 10 nM to 1000 μM. Qualitative analysis of cell cytoskeletal organization was obtained by immunostaining with talin and integrin α5. It was clearly indicative of well spreading of cells in the presence of all glycopolymers at lower concentrations but with an increase in the concentration (10 and 100 μM) showed significant change in the cell surface morphologies, despite having good cell adhesion and viability as compared to the control conditions. The use of di-block glycolpolymers at?≤?100 μM of the concentration showed very good osteoblast cells adhesion and viability response; however at higher concentrations (1000 μM) of glycopolymers > 80% of cells lost their viability.     

Identification of the Trail Pheromone of the Pavement Ant Tetramorium immigrans (Hymenoptera: Formicidae)

Journal of Chemical Ecology - Four species of Tetramorium pavement ants are known to guide foraging activities of nestmates via trail pheromones secreted from the poison gland of worker ants, but...     

A Qualitative Review on Tunnel Field Effect Transistor- Operation,Advances, and Applications

Silicon - Tunnel Field Effect Transistor (TFET) has become one of the promising devices to be part of Integrated circuits as the technology advances to the nanoscale. A TFET has many advantages...     

New approach for prediction of influence of vehicle dynamics parameters on instability of unmanned track vehicle using robotic approach

Journal of Mechanical Science and Technology - Achieving stability of unmanned, heavy tracked vehicles is challenging, especially under conditions of teleoperation because the remote operator...     

Numerical investigation of heat transfer and friction factor in ribbed triangular duct solar air heater using Computational fluid dynamics (CFD)

Journal of Mechanical Science and Technology - The Computational fluid dynamics (CFD) based analysis is carried out to investigate the thermal and hydraulic performance of circular rib roughened...     

Parameter optimization of friction stir welding of cryorolled AA2219 alloy using artificial neural network modeling with genetic algorithm

In this paper, parameter optimization of FSW of cryorolled AA2219 alloy was carried out to obtain defect free weld joint with maximum weld strength. To achieve this, artificial neural network (ANN) was used to model the relationship between the input parameters and the mechanical and corrosion properties (output) of the weld joints. The optimal FSW parameters were determined by genetic algorithm (GA). The feasible solution of the GA was tool rotational speed of 1005 rpm, tool travel speed of 20 mm/min and tool tilt angle of 3°. The feasible parameter was used to weld and check the ability of the parameter to produce better weld joint than the L₉ orthogonal array parameters. The weld, subjected to the confirmation test, was investigated by means of metallurgical, mechanical, and corrosion testing. This process reduces the costs associated with trial runs to obtain optimal parameters and also the production cost of the cryorolled (CR) plate which is high.     

Polyethers with phosphate pendant groups by monomer activated anionic ring opening polymerization: Syntheses,characterization and their lithium-ion conductivities

This paper describes the preparations and lithium-ion conductivities of various solid polymer electrolytes for potential use in high-energy density lithium-ion batteries. The ring opening polymerization of epoxides (M1–M6), catalyzed by Zn(II), Cu(II) and Cd(II) complexes in the presence of tetrabutylammonium bromide (TBAB), yielded polyethers (P1–P6) in which phosphates were attached as pendant groups. A reaction condition where Zn(II) catalyst used slightly excess to TBAB increased the polymerization rate remarkably and yielded the polyethers with higher molar masses in a short time. These polymerizations proceeded following a “monomer activated anionic ring opening polymerization” mechanism. These living like polymerizations also progressed according to “formation of polymer chain per initiator” model. The solid-state lithium-ion conductivities of these polymers were examined using lithium bis(trifluoromethanesulfonyl)imide (LiTFSI). The conductivity of one of the solid polymer electrolytes with 40 wt% of LiTFSI was 5.2 × 10⁻⁵ S cm⁻¹ at room temperature and 2.9 × 10⁻⁴ S cm⁻¹ at 80 °C.     

Photovoltaics literature survey (No. 115)

In order to help keep readers up‐to‐date in the field, each issue of Progress in Photovoltaics will contain a list of recently published journal articles that most relevant to its aims and scope. This list is drawn from an extremely wide range of journals, including IEEE Journal of Photovoltaics, Solar Energy Materials and Solar Cells, Renewable Energy, Renewable and Sustainable Energy Reviews, Journal of Applied Physics, and Applied Physics Letters. To assist the reader, the list is separated into broad categories, but please note that these classifications are by no means strict. Also note that inclusion in the list is not an endorsement of a paper's quality. If you have any suggestions please email Ziv Hameiri at ziv.hameiri@unsw.edu.au