Realisation of CdS/Mn3O4nanocomposites for potential Photocatalytic Applications

The present work reports the realisation of high-quality crystalline CdS/Mn3O4(CM) nanocomposites by a simple cost-effective chemical method in air atmosphere. The authors have performed theoretical calculations and experimental analysis in order to understand the synthesised nanocomposites. X-ray diffraction results showed that the CM nanocomposites were cubic and orthorhombic mixed structure which is in good agreement with the theoretical studies. Field emission scanning electron microscopy images of CM confirmed the formation of well distributed nanocomposites. The outcomes of DFT calculations provide results for the bandgap calculation of pure CdS, Mn3O4and the CM nanocomposites. Photoluminescence studies with interesting visible light absorption demonstrated the great potentiality of the as-synthesised nanocomposites towards photocatalytic applications that could be a detailed research scope for the authors' future studies. © 2020 Institution of Engineering and Technology. All rights reserved.Acknowledgments: The author P. Joice Sophia kindly acknowledges DST-INSPIRE Faculty Scheme (DST/INSPIRE/04/2016/ 000292) and SERB-EMR (EMR/2017/004764) for the financial support and funding. One of the authors, M. Rajesh Kumar thanks the contract no. 40/is2

Realization of Ti MOF/MoS2 Hybrid Nanostructure and Their Catalytic Activity Towards 4-Nitrophenol Reduction

The development of effective catalysts for catalytic reduction of the toxic 4-Nitrophenol (4-NP) into useful 4-Aminophenol (4-AP) has received wide interest. Herein, we report the synthesis of Titanium Metal–Organic Framework (Ti-MOF)/MoS2 hybrid nanostructure as potential catalyst for the reduction of 4-NP. Various characterization tools such as FESEM, TEM, XRD, and XPS have been used to conduct the morphological and structural analysis of the hybrid nano catalyst. The catalytic studies suggest that the as-prepared Ti-MOF, MoS2, and Ti-MOF/MoS2 hybrid nanostructures effectively catalyze the reduction of 4-NP to 4-AP in the presence of NaBH4. The rate constant (Kapp) of MOF/MoS2 hybrid nanostructure is found to be 1.208 min−1, which proves its higher catalytic performance in comparison with the pristine samples. Additionally, its preeminent reusability performance makes MOF/MoS2 hybrid nanostructure to be used as effective and practical catalyst. Through this work, the potential for the heterostructure's high catalytic activity is conversed and a possible reaction mechanism is proposed. Our findings confirm that the hybrid MOF@MoS2 nanoflakes have provided a promising interface for the hydrogenation procedure on the catalytic surface, thereby making it an excellent catalytic material to be further investigated. © 2022 The Authors.The authors greatly acknowledge the Photonics Research facility of Aaivalayam-DIRAC, Coimbatore, India for the funding and laboratory support. One of the authors (Manavalan Rajesh Kumar) thanks to the contract no. 40/is2

Ambitions of a global city: Arts, culture and creative economy in 'Post-Crisis' Singapore

10.1080/10286632.2011.639876International Journal of Cultural Policy183279-29

Fingerprints for Structural Defects in Poly(thienylene vinylene) (PTV): A Joint Theoretical–Experimental NMR Study on Model Molecules

In the field of plastic electronics, low band gap conjugated polymers like poly(thienylene vinylene) (PTV) and its derivatives are a promising class of materials that can be obtained with high molecular weight via the so-called dithiocarbamate precursor route. We have performed a joint experimental- theoretical study of the full NMR chemical shift assignment in a series of thiophene-based model compounds, which aims at (i) benchmarking the quantum-chemical calculations against experiments, (ii) identifying the signature of possible structural defects that can appear during the polymerization of PTV's, namely head-to-head and tail-to-tail defects, and (iii) defining a criterion regarding regioregularity

Living The Next Lap : Towards a tropical city of excellence

Singapore40 p.: fig.; 30 cm

Structure and polymerisation behaviour of cadmium 10,12-pentacosadiynoate Langmuir-Blodgett films

Two different types of Y-films (a Y-film from Z-type deposition and a Y-film from Y-type deposition) have been observed during the Langmuir-Blodgett (LB) film deposition of metal diynoates, but their structural characterisation has not received much attention. In the present work, a study of LB film deposition of cadmium 10,12-pentacosadiynoate, for evaluating the effects of monolayer aging and concentration of spreading solution, has been carried out and three different types of Y-films of cadmium 10,12-pentacosadiynoate have been obtained. Structural characterisation and study of the topochemical polymerisation of different types of films show remarkably large differences in their bilayer spacing and diacetylene polymerisation behaviour. This study shows that Y-films obtained by overturning in the Z-type buildup process are structurally quite different from the Y-films obtained from the Y-type build-up process

Deposition of thin multilayers of Titanium arachidate and 10,12-pentacosadiynoate using the Langmuir-Blodgett technique

Multilayered thin films of titanium arachidate and 10,12-pentacosadiynoate were deposited by employing the Langmuir-Blodgett (LB) technique. Stable monolayers of titanium arachidate were formed on an aqueous subphase and were transferred onto a substrate by a vertical dipping process as Y-type multilayers at 23 degrees C. Lowering of the subphase temperature to 10 degrees C led to Z-type deposition. In the case of diynoate, only Z-type deposition was observed at subphase temperatures of 10 degrees C as well as 23 degrees C. The multilayer films were characterized by X-ray diffraction (XRD), X-ray photoelectron spectroscopy, inductively coupled plasma atomic emission spectroscopy analysis and UV-visible and Fourier transform IR (FTIR) spectroscopy. The XRD results revealed that the multilayers of both arachidate and diynoate do not contain any defined layer spacing. FTIR results indicate that the film deposited at higher pH of 6.1 consists of a mixture of the acid and the arachidate salt. UV irradiation of diynoate LB films resulted in polymerization, indicating the presence of crystalline domains in these LB films

Form tolerances investigation in EDM process for super alloys using multiple holes electrodes

200-204The present work focuses on experimental quality analysis of electrical discharge machining (EDM) of two super alloys namely Inconel 718 and Inconel 625 with different diameter of hole of multiple holes copper electrodes. The diameter of hole of multiple holes in electrode, pulse current and (Ton) pulse on time have been chosen as process parameters to conduct the experiment trails. The MRR, EWR and form tolerance have been considered as output responses

Optimization of machining parameters of EDM while machining Inconel 718 for form tolerance and orientation tolerance

391-397This paper demonstrates the effectiveness of optimizing multiple characteristics of electrical discharge machining (EDM) of Inconel 718 using copper electrodes having different shapes via Taguchi method-based Grey analysis. The modified algorithm adopted here is used successfully for both detraining the optimum settings of machining parameters and for combining multiple quality characteristic into one numerical value called Grey relational grade or rank. The essential parameters like peak current, pulse on time and pulse off time are chosen to conduct the experiments on multiple characteristics namely material removal rate (MRR), electrode wear rate (EWR), form tolerance namely straightness and orientation tolerance like perpendicularity and angularity. Then, ANOVA is used to find out the parameter which significantly affects the other parameters. The experimental results have shown that the machining performance on multiple characteristics in the EDM process is improved effectively through this approach