R. K. Gupta

Color Kinetics of Aonla Shreds with Amalgamated Blanching During Drying

Kinetics of color changes of aonla (Emblica officinalis) shreds were investigated using objective colorimetric measurements during drying with different blanching treatments. Kinetic parameters chroma, hue, total color difference, and browning index for the color change were determined using Hunter L, a, b values. The drying process changed all three color parameters (L, a, b), causing a color shift towards the darker region. Parameters L and b decreased and a-value increased during drying. The reaction associated with color change followed zero-order reaction kinetics. The minimum change was observed in the KMS (potassium metabisulphite) blanched shreds.

High-Performance Stable Field Emission with Ultralow Turn on Voltage from rGO Conformal Coated TiO2 Nanotubes 3D Arrays

A facile method to produce conformal coated reduced graphene oxide (rGO) on vertically aligned titanium oxide (TiO2) nanotubes three dimensional (3D) arrays (NTAs) is demonstrated for enhanced field emission display applications. These engineered nano arrays exhibit efficient electron field emission properties such as high field emission current density (80 mA/cm2), low turn-on field (1.0 V/μm) and field enhancement factor (6000) with high emission current stability. Moreover, these enhancements observed in nano arrays attribute to the contribution of low work function with non-rectifying barriers, which allow an easy injection of electrons from the conduction band of TiO2 into the Fermi level of reduced graphene oxide under external electric field. The obtained results are extremely advantageous for its potential application in field emission devices.

Solution Treatment and Aging of Thick Rings from Titanium Alloy TI6AL4V

Rings from titanium alloy Ti6Al4V used for making pressure vessels for launch vehicles are studied after annealing and after solution treatment and aging. The mechanical characteristics of the rings after quenching and aging do not always have the specified values, especially in thicker sections. The studied rings are of two sizes and have a final wall thickness of 30.5 and 17.5 mm. The effect of the temperatures of solution treatment and aging, of the quenching rate, and of the section thickness on the mechanical properties is studied, and the process is updated to provide the required properties.

Experimental observation of spatially resolved photo-luminescence intensity distribution in dual mode upconverting nanorod bundles

A novel method for demonstration of photoluminescence intensity distribution in upconverting nanorod bundles using confocal microscopy is reported. Herein, a strategy for the synthesis of highly luminescent dual mode upconverting/downshift Y1.94O3:Ho3+0.02/Yb3+0.04 nanorod bundles by a facile hydrothermal route has been introduced. These luminescent nanorod bundles exhibit strong green emission at 549 nm upon excitations at 449 nm and 980 nm with quantum efficiencies of ~6.3% and ~1.1%, respectively. The TEM/HRTEM results confirm that these bundles are composed of several individual nanorods with diameter of ~100 nm and length in the range of 1–3 μm. Furthermore, two dimensional spatially resolved photoluminescence intensity distribution study has been carried out using confocal photoluminescence microscope throughout the nanorod bundles. This study provides a new direction for the potential use of such emerging dual mode nanorod bundles as photon sources for next generation flat panel optical display devices, bio-medical applications, luminescent security ink and enhanced energy harvesting in photovoltaic applications.

Study of Aluminum Alloy AA2219 After Heat Treatment

Results are given for a study of the mechanical properties of aluminum alloy AA2219 after thermomechanical treatment by different regimes, including different (in form and degree) cold plastic deformation.

Reactive and liquid-phase sintering techniques

Powder metallurgy is one of the most versatile techniques to produce near net shaped components. The sintering process is one of the key steps involved in the powder metallurgy route of manufacturing. Among the various sintering processes, reaction sintering and liquid phase sintering are the most commonly applied techniques which exploit the formation of liquid to fill the pores/voids as well as aids diffusion, transport of matter in achieving higher densification as compared to solid-state sintering of intermetallics, ceramics, as well as intermetallic composites. Along with the above processes, variants of the above techniques like transient liquid phase sintering, self propagating high temperature synthesis, pressureless reaction synthesis, etc. have also been discussed in this chapter. Supersolidus liquid phase sintering as well as microgravity LPS have also been touched upon. The various process parameters/factors affecting the reaction kinetics, porosity/densification, etc. have also been discussed. The mechanisms of the sintering processes have been discussed along with the applications of various processes for metals, ceramics, and composites along with a typical example. The chapter concludes with the future scope of work in this area.

The Roadmap for Enhancing University–Industry Research Collaboration in India:

In this age of technology-led development and stiff international competition over Intellectual Property Rights (IPRs), developing countries, with their limited financial capabilities, face the challenge of creating appropriate environment that could facilitate the creation and commercialisation of technologies. The recognition of poor scientific outputs as a hindrance to the growth of domestic industry has brought research on the development agenda. This article focuses on university–industry research collaborations as one of the ways to kick-start innovation-led economic growth in India. It explores the evolution of relevant policy paradigm in India and presents the relevant highlights of National IPR Policy 2016. It identifies the impediments in the way of creative university–industry collaborations and offers solutions to attain optimum synergy between the academia and industry.

Simulation of Articulated Robotic Manipulator & It’s Application in Modern Industries

Simulation has been recognized as an important research tool since the beginning of the 20th century. Invention of computers boosted the simulation capability that’s why simulation is now a powerful tool supporting the design, planning, analysis, and decisions in different areas of research and development. In the present work, a CAD/CAE integrated system for Cartesian, cylindrical & articulated type robot manipulators are developed. The D–H (Denavit–Hartenberg) coordinate transformation method was used to perform the robot position analysis, according to the transformation matrices; P. Corke Robotic toolbox for MATLAB is used for the robot position analysis. Pro/ENGINEER (Pro/E) is used to construct the robot manipulator parametric solid models; Pro/Mechanica is used for the kinematic simulation and analysis of working envelop. Finally an error model is generated to estimate the positional error in all three manipulator configurations. This integrated system not only promotes automation capabilities for robot manipulator production, but also simplifies the CAD/CAE process for a robot manipulator & provides the idea for selecting the robotic manipulator for a particular application.