Iridium-based light-emitting electrochemical cells containing ionic liquids in the luminous layer

To fabricate transition metal complex-based LECs (light-emitting electrochemical cells), ([Ir(ppy)₂(5,6-dime-1,10-phenthroline)]PF₆ was synthesized and used as a luminous material and ILs (ionic liquids) were incorporated into a luminous layer, in which two types of ionic liquid were used; 1-butyl-3-methylimidazolium hexafluorophosphate (BMIMPF₆) and 1-butyl-3-methylimidazolium tetrafluoroborate (BMIMBF₄). ILs were added to a [Ir(ppy)₂(5,6-dime-1,10-phenthroline)]PF₆ luminous layer to improve ionic conductivity and light intensity. Both ILs significantly increased the current density and luminance. Due to the small molecule of BF₄^?, turn-on time was reduced and ionic conductivity was increased. However, the device stability was sacrificed. High current efficiency of 34.5 cd/A was investigated at 7 V of BMIMPF₆-doped luminous layer. The LECs based on [Ir(ppy)₂(5,6-dime-1,10-phenthroline)]PF₆ gave yellow emission color when ILs were added into light-emitting layer, and no significant change of color has been found in this study.     

Wind Velocity Sensorless Maximum Power Point Tracking Algorithm in Grid-connected Wind Energy Conversion System

This article proposes a wind velocity sensorless hill-climb searching algorithm in the grid-connected field-oriented controlled permanent magnet synchronous generator based wind energy conversion system. The proposed method improves the speed and accuracy of initial tracking. Pseudo-optimum points are used to track the exact optimum points using the power versus speed characteristics of a wind turbine for various wind velocities. This research emphasizes that the pseudo-optimum points using the power versus speed characteristics are always less than and much nearer to the exact optimum points. The small-step forward tracking after pseudo-optimum points improves the accuracy of this algorithm. Moreover, this method improves the tracking speed for various wind velocities. The system used for this research consists of a back-to-back sinusoidal pulse-width modulation converter between the generator and the grid. The performance of the proposed method is analyzed mathematically and verified by simulation using MATLAB/Simulink software (The Mathworks, Natick; Massachusetts, USA).     

Simple position sensorless starting method for brushless DC motor

Position sensorless methods for brushless DC motors based on back-EMF zero crossing suffer from a starting problem since there is no back-EMF at standstill. A simple method by which the motor is started from standstill up to a speed wherein sensorless methods will be able to detect the correct commutation instants is proposed. The proposed method relies on a difference of line voltages measured at the terminals of the motor. It is shown that this difference of line voltages provides an amplified version of an appropriate back-EMF at its zero crossings. It is further demonstrated that this information can be used to trigger devices so as to develop an accelerating torque from zero speed. This method is simple to implement and it can reliably start the motor even with load. The effectiveness of the proposed method is demonstrated through simulation and hardware results.     

Standardised Reference Data Sets Generation for Coordinate Measuring Machine (CMM) Software Assessment

Rapid and accurate in-process measurement has recently become more common in product cycles, especially for producing parts having 3D contoured shapes. As a result, the ability to analyse large quantities of dimensional data requires today’s coordinate measuring machines (CMM) to employ their extreme functionality. With the increasing demand for performance of the software supplied for a CMM, the testing methods for these software packages must be rigorous, stable, and efficient. Motivated by the aforementioned demand, this work is intended to design and develop an algorithm and computer code to generate the reference data sets representing the coordinates of Gaussian associated features for CMM measured parts. These reference data sets can be used to test the CMM software submitted for approval to the National Institute of Standards and Technology (NIST). A generic algorithm for the development of the data sets is proposed and the program code is designed and developed by employing object oriented concepts. Dynamic errors during measurement are also accounted for, using Fourier harmonics representing the form errors and noise in the measured data. The data sets, being an integral part of the proposed International Standard – ISO 10360, will become a significant step towards the standardisation of software testing procedures for coordinate measuring machines.     

Performance characteristics of pentacene-based organic photovoltaic cells

We demonstrate the maximum power conversion efficiency of 3.89% from organic photovoltaic cells using pentacene as a hole transport layer with PIN structure of ITO/poly(3,4-ethylenedioxythiophene)–poly(styrenesulfonate) (PEDOT:PSS)-glycerol/pentacene/pentacene:C₆₀/C₆₀/BCP (bathocuproine)/Al under standard AM 1.5 illumination (100 mW/cm²). To achieve high power conversion efficiency, the optimization of thickness of pentacene and glycerol-doped poly(3,4-ethylenedioxy-thiophene)–poly(styrene sulfonate) (G-PEDOT:PSS) as well as pentacene:C₆₀ (1:1) thin film as an active layer was accomplished. Our results show that the PIN structure with enlarged interface between pentacene and C₆₀ thin films increases the power conversion efficiency of the devices than the PN devices. The morphology of pentacene thin film with various thicknesses and glycerol-doped PEDOT:PSS layers crucially affected the performance characteristics of pentacene-based photovoltaic cells.     

Brain targeted delivery of anticancer drugs: prospective approach using solid lipid nanoparticles

A brain tumour is amongst most devastating and challenging condition to overcome with suitable treatment as the drug has to cross the blood–brain barrier (BBB) with several physiological barriers like opsonisation by the reticuloendothelial system. Presently various techniques such as surgical, chemotherapeutic agents, and radiotherapy techniques have performed to extend the lifespan of patients diagnosed with glioblastoma, which did not maximise the overall survival of patients with a tumour. Nanotechnology is relied upon to diminish the requirement for intrusive methods for conveyance of therapeutics to the central nervous system. Colloidal nanocarriers sizing range 1–1000 nm have been utilised to cross BBB delivers the drug at cell levels with enhanced bioavailability and reduced toxicity. However, solid lipid nanoparticles (SLNs) are considered a highly flexible carrier for more successful remedially in brain tumour. The treatment of a brain tumour via SLNs is gaining greater potency due to its inimitable size and lipidic nature. This review focuses and represents the current strategies of SLNs in the brain tumour treatment with appropriate techniques adopted are highlighted. Based on this review, the authors concluded that SLNs embrace exclusive promising lipidic nanocarrier that could be utilised to target a brain tumour effectively.Inspec keywords: brain, cancer, nanoparticles, blood, molecular biophysics, tumours, nanomedicine, neurophysiology, radiation therapy, colloids, biomedical materials, drug delivery systems, nanofabrication, drugs, cellular biophysicsOther keywords: chemotherapeutic agents, radiotherapy techniques, central nervous system, colloidal nanocarriers sizing range 1–1000 nm, BBB, drug, solid lipid nanoparticles, brain tumour therapeutical uses, lipidic nature, brain tumour treatment, brain targeted delivery, anticancer drugs, prospective approach, blood–brain barrier, physiological barriers, reticuloendothelial system, surgical agents, lipidic nanocarrier, size 1.0 nm to 1000.0 nm     

Analysis of performance and emission patterns of novel biofuel feedstock neat coconut fatty acid distillate (CFAD) fuelled single-cylinder diesel engine

This study examined the potential of using coconut fatty acid distillate (CFAD), a by-product of the processing of edible oils, as a diesel engine fuel. The major novelty of this study is to assess the CFAD as a viable feedstock of biodiesel to address global energy demands. CFAD has not been specifically researched as a feedstock for producing biodiesel or as a fuel for diesel engines, despite the fact that numerous studies on the production and performance of biodiesel have already been conducted. Fourier transform infrared (FTIR) spectroscopy, gas chromatography (GC), and FTIR were used to analyze the fuel. According to the results of the GC test, CFAD oil contains 91.53% saturated fatty acids, compared with only 8.47% unsaturated fatty acids. High saturation values can be seen in myristic acid (16.92%) and lactic acid (45.33%). Longer hydrocarbon chain lengths indicate higher energy density and boiling point, which also indicate lesser volatility. At a frequency of 1708.54 cm⁻¹, C─H stretching vibrations have been identified through FTIR investigation. The vibrations of C─C stretching at 1465.47 cm⁻¹ indicate the presence of alkenes/fingerprint phase. The blends used for this investigation include 90% diesel with 10% CFAD (CFAD10), 80% diesel with 20% CFAD (CFAD20), 70% diesel with 30% CFAD (CFAD30), and 100% CFAD. The CFAD 10%, 20%, and 30% blends as well as the CFAD100 had brake thermal efficiency values of 27.24%, 26.23%, 24.88%, and 21.52%, correspondingly, at full load. The average increment in brake-specific energy consumption for CFAD10, CFAD20, CFAD30, and CFAD100 over diesel fuel was 8.23%, 10.88%, 13.77%, and 25.90%, respectively. The behavior of CFAD exhibits reduced cylinder pressure because of the large content of moderate saturated fatty acids in this substance. The net heat release rate (NHRR) and cylinder pressure have a similar relationship in that the NHRR increases with increasing diesel volume. In comparison to diesel, the CO emissions from the CFAD20, CFAD30, and CFAD100 blends increased by 10.79%, 16.66%, and 35.89% at maximum load, respectively. It has been reported that NO_x is reduced more significantly the more CFAD is present in the mixture. The blend CFAD10 had the least amount of smoke. The high viscosity of the CFAD and its blends influences the fuel droplets range and the development of spray in the cylinder, which results in delayed combustion and higher unburned hydrocarbon emissions.     

Effect of ionic liquids on the electroluminescence of yellowish-green light-emitting electrochemical cells using bis(2-(2,4-difluorophenyl)pyridine)4,7-diphenyl-1,10-phenanthroline-iridium(III) hexafluorophosphate

A cationic iridium complex [Ir(dfppy)₂(dpphen)]PF₆, where dfppy is 2-(2,4-difluorophenyl)pyridine, dpphen is 4,7-diphenyl-1,10-phenanthroline and PF₆⁻ is hexafluorophosphate, has been synthesized and its photophysical and electrochemical properties were investigated. Light-emitting electrochemical cells (LECs) based on this complex were fabricated using air stable electrodes and emits yellowish-green light (533 nm) with Commission Internationale de L’Eclairage (CIE) coordinates of (0.35, 0.59) at 4 V. Effect of two different imidazolium based ionic liquids (ILs) viz, 1-butyl-3-methylimidazolium hexafluorophosphate (BMIMPF₆) and 1-ethyl-3-methylimidazolium hexafluorophosphate (EMIMPF₆) on the active layer has been studied and the luminance and the current density of the devices were found to be enhanced with increasing ionic conductivities.     

Development of tamoxifen‐loaded surface‐modified nanostructured lipid carrier using experimental design: in vitro and ex vivo characterisation

The present study aimed to develop a surface‐modified biocompatible nanostructured lipid carrier (NLCs) system using polyoxyethylene (40) stearate (POE‐40‐S) to improve the oral bioavailability of poorly water‐soluble Biopharmaceutics Classification System class‐II drug like tamoxifen (TMX). Also aimed to screen the most influential factors affecting the particle size (PS) using Taguchi (L₁₂ (2¹¹)) orthogonal array design (TgL₁₂ OA). Then, to optimize the TMX loaded POE‐40‐S (P) surface‐modified NLCs (TMX‐loaded‐PEG‐40‐S coated NLC (PNLCs) or PNLCs) by central composite design (CCD) using a four‐factor, five‐level model. The most influential factors affecting the PS was screened and optimized. The in‐vitro study showed that increased drug‐loading (DL) and encapsulation efficiency (EE), decreased PS and charge, sustained drug release for the prolonged period of the time with good stability and suppressed protein adsorption. The Ex‐vivo study showed that decreased mucous binding with five‐fold enhanced permeability of PNLC formulation after surface modification with POE‐40‐S. The in‐vitro cytotoxicity study showed that the blank carrier is biocompatible and cytotoxicity of the formulation was dependent on the concentration of the drug. Finally, it can be concluded that the surface‐modified PNLCs formulation was an effective, biocompatible, stable formulation in the enhancement of dissolution rate, solubility, stability with reduced mucus adhesion and increased permeability thereby which indicates its enhanced oral bioavailability.Inspec keywords: nanoparticles, cellular biophysics, solubility, drug delivery systems, toxicology, adsorption, adhesion, dissolving, biomedical materials, encapsulation, polymers, proteins, nanomedicine, permeability, particle size, electrokinetic effectsOther keywords: water‐soluble BCS class‐II, TgL₁₂ OA, TMX‐loaded POE‐40‐S surface‐modified NLC, surface‐modified PNLC formulation, lipid‐based NLC system, oral bioavailability, stable formulation, biocompatible formulation, blank carrier, in vitro cytotoxicity, surface modification, PNLC formulation, drug release, central composite design, orthogonal array design, encapsulation efficiency, steric stabilisation effect, particle size, dissolution rate, polyoxyethylene stearate, surface‐modified biocompatible carrier system, systemic toxicity, water‐soluble drug, tamoxifen‐loaded surface‐modified nanostructured lipid carrier     

Measurement of thermal conductivity of fluid using single and dual wire transient techniques

A modified measurement device to measure thermal conductivity of fluids using transient hot-wire technique has been designed, developed, tested and presented in this paper. The equipment is designed such that the thermal conductivity could be measured using both single wire sensor of different length and dual wire sensor. The sensor, which is also a heater, is a platinum micro-wire of 50 μm diameter. The influence of wire length on the measurement of thermal conductivity of fluids is tested using two single wires of length 50 mm and 100 mm. The thermal conductivity is also measured using a dual hot wire arrangement; which is achieved by placing the 100 mm and 50 mm wires in a Wheatstone bridge with the 100 mm wire as the sensor and 50 mm wire as a compensation wire. The apparatus requires a 100 ml of test fluid to perform the experiment. The testing temperature of the test fluid during the experimentation can be suitably varied by the choice of heat exchange fluid used in the apparatus. Water is chosen as testing fluids for primary standards. When compared to single wires, the thermal conductivity of the fluids measured is consistent with dual-wire method with an uncertainty of ±0.25%.