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Switching power converters for photovoltaic (PV) applications with high gain are rapidly expanding. To obtain better voltage gain, low switch stress, low ripple and cost-effective converters, researchers are developing several topologies.

It was decided to use the particle swarm optimization approach for this system in order to compute the precise PI controller gain parameters under steady state and dynamic changing circumstances. A high-gain q- ZS boost converter is used as an intermittent converter between a PV and brushless direct current (BLDC) motor to attain maximum power point tracking, which also reduces the torque ripples. A MATLAB/Simulink environment has been used to build and test the positive output quadratic boost high gain converters (PQBHGC)-1, PQBHGC-8, PQBHGC-4 and PQBHGC-3 topologies to analyse their effectiveness in PV-driven BLDC motor applications. The simulation results show that the PQBHGC-3 topology is effective in comparison with other HG cell DC–DC converters in terms of efficiency, reduced ripples, etc. which is most suitable for PV-driven BLDC applications.

The simulation results have showed that the PQBHGC-3 gives better performance with minimum voltage ripple of 2V and current ripple of 0.4A which eventually reduces the ripples in the torque in a BLDC motor. Also, the efficiency for the suggested PQBHGC-3 for PV-based BLDC applications is the best with 99%.

This study is the first of its kind comparing the different topologies of PQBHGC-1, PQBHGC-8, PQBHGC-4 and PQBHGC-3 topologies to analyse their effectiveness in PV-driven BLDC motor applications. This study suggests that the PQBHGC-3 topology is most suitable in PV-driven BLDC applications.

The purpose of this paper is to assess the possibility of cross-linking silk fabric using citric acid (CA) as the cross-linking agent and nano-TiO2 (NTO) particles as a catalyst at low temperature and under UV irradiation. This paper also assesses the possibility of treated samples with suitable combinations of CA and NTO to impart multiple functional properties such as self-cleaning and antimicrobial properties.

In this research, ß-cyclodextrin (ß-CD) grafted onto silk fabric using CA as a crosslinking agent and NTO particles as a catalyst through a pad-dry-cure technique and with UVA irradiation. The effects of different concentrations of CA, ß-CD and NTO particles on some properties of the treated samples are evaluated, and the optimum finishing conditions are obtained. The author also investigated the washing durability of the modified product after ten times of washing.

The results showed that CA plays the role of a linking agent through an esterification reaction with the hydroxyl groups of both ß-CD and silk fabrics and improves the durability of materials on the textile surface. Also, the silk fabrics treated with CA only were found to have excellent photocatalytic properties and better antibacterial activity than the control sample and the fabrics treated with a mixture of ß-CD/CA.

This study was conducted to achieve multiple functions such as antibacterial and photocatalytic activities, good dry crease recovery angle and wet crease recovery angle behavior without a significant adverse effect on the Yellowness index and tensile properties for treated silk fabrics.

The purpose of this study is the chemical grafting of β-Cyclodextrin (β-CD) onto silk fabrics by the use of butane tetracarboxylic acid (BTCA) as a crosslinking agent and nano-TiO₂ (NTO) as a catalyst. The effects of different parameters involved in this particular process, e.g. β-CD, BTCA and NTO concentrations, are examined using the artificial neural network (ANN). The method is evaluated for its ability to predict certain properties of treated fabrics, including grafting yield, dry crease recovery angle (DCRA) and wet crease recovery angle (WCRA), tensile strength, elongation at break and methylene blue dye absorption.

This study was conducted to describe the cross-linking of silk with 1,2,3,4-BTCA as a crosslinking agent in a wet state at low temperatures using NTO catalyst to improve the dry and wet wrinkle recovery (DCRA and WCRA) of silk fabrics. An ANN was also used to model and analyze the effects of BTCA, β-CD and NTO concentrations on the grafting percentage and some properties of the treated samples.

According to the results, the wet and dry wrinkle recovery of the silk fabrics was improved for about 38% and 11%, respectively, as compared to the non-cross-linked fabrics, without significantly affecting the tensile strength retention of the fabrics.

This research model and analyze the effects of BTCA, β-CD and NTO concentrations on the grafting percentage and some properties of the treated samples for the first time.