Effect of various pre-harvest treatments on shelf life and morphological characteristics of fruits of mango (Mangifera indica L.) var. ‘Amrapali’

The mango is considered as ‘king of fruits’ in India due to its delicious taste and nutritional status. Extension of fruit shelf life is a prime importance for availability of fresh fruit in market for longer duration and distance transportation. India is the largest producer and a prominent exporter of mango in the world.In this context, the study was conducted to evaluate the effect of preharvest spray of different chemicals and plant growth regulators (PGRs) on mango var. ‘Amrapali’ for shelf life and its quality. As ‘Amrapali’ has regular bearer with very good flavor and taste with a late maturing character, selected for shelf life studies. The fruits of mango weresprayed with chemicals viz. CaCl2 1%, CaCl2 2%, Ca(NO3)2 1%, Ca(NO3)2 2%, KNO3 1%, KNO3 2%, GA3 25 mg/l, GA3 50 mg/l, Ethrel 0.1 ml/l and Ethrel 0.2 ml/l prior to harvest. After harvesting, fruits were stored under ambient storage condition. Among all the treatments, GA3 25 mg/l treatment recorded significantly highest fruit length, fruit diameter, fruit volume and fruit weight at harvest and at fully ripe stage. Application of CaCl22% resulted in significantly minimum physiological loss in weight consistently from 2nd day to 16th day of storage besides significantly highest shelf life and quality. Hence, this intervention can contribute in preserving physical and chemical quality attributes for maximum acceptance by consumers

DYNAMIC BEHAVIOUR OF DIRECT METAL LASER SINTERED TI-6AL-4V (ELI) UNDER HIGH STRAIN RATES IN COMPRESSION LOADING

ArticleDeformation behaviour under dynamic compression of Ti-6Al-4V (ELI) produced through additive manufacturing in two different forms; as-built (AB) and stress relieved (SR), was investigated. Both AB and SR specimens were printed using the DMLS EOSINT M280 system. Compression tests were performed on the specimens at strain rate ranges lying between (300s-1-400s-1) and (600s-1-700s-1) using a Split Hopkinson Pressure Bar. This paper presents Scanning Electron Microscope (SEM) micrographs of the resulting fracture surfaces of the tested specimens, as well as scanned surfaces of through cuts, parallel and perpendicular to the load-direction of specimens that did not fracture, with a focus on the microstructural features peculiar to shear and adiabatic deformation

Variation of Impact Toughness of As-Built DMLS Ti6Al4V (ELI) Specimens with Temperature

Published ArticleThe response of direct metal laser sintering (DMLS) produced Ti6Al4V (ELI) to impact was investigated using an instrumented Charpy impact test machine and V-notch specimens. Impact toughness testing was conducted over the temperature range of -130oC to 250oC. The effect of the orientation of the V-notch, with reference to the base plate, was investigated. The results indicated that the samples that were produced with the V-notch facing the base plate (LO) had better values of impact toughness than those that were produced with the V-notch facing away from the base plate (UP) over most of the test temperatures. The study further established that as-built DMLS Ti6Al4V (ELI) retains appreciable notch toughness, even at extremely low temperatures

Experimental Investigation of Dynamic Elastic Properties of Reinforced Coconut Shell Powder/Epoxy Resin Composites

ArticleThe purpose of this study is to investigate experimentally the dynamic elastic behavior of a coconut shell powder filler reinforced epoxy resins composite of different filler sizes and volume fractions. The dynamic mechanical analysis of coconut shell powder reinforced epoxy composites was carried out with special reference to the effect of filler loading, and temperature. The result showed that the core properties of the components, morphology of the system and the nature of interface between the phases determine the dynamic mechanical properties of the composite. Below the glass transition temperature, the storage modulus was generally found to increase with increasing weight fraction of the reinforcing filler and a reverse trend as temperature rose through the glass transition temperature. The loss modulus was generally seen to decrease with decreasing filler weight fraction for temperatures below the glass transition point and vice versa. Moreover, the curves for loss modulus were seen to shift to lower temperatures with increasing filler content, signifying a decreasing glass transition temperature with increasing filler content. The damping factor was seen to decrease in magnitude with increasing content of filler, with a trend of the peak values shifting to the lower temperatures

Investigating The Mechanical Properties Of Reinforced Coconut Shell Powder/Epoxy Resin Composites

ArticleExperimental investigations were conducted to determine the mechanical properties of coconut shell powder filled epoxy resin composites. The results obtained showed that the modulus of elasticity and hardness of the composite increased with increasing percentage weight of both the 150 μm and 212 μm CSP particle sizes. The tensile strength, percent elongation and impact toughness of the composite were all seen to decrease as the reinforcement increased. The investigations carried out showed that the addition of coconut shell powder to epoxy resin only raised the values of the specific mechanical properties of tensile stiffness and hardness. Different models were used to predict the mechanical properties of the CSP composites. The method of Nicolais-Narkis predicted values of tensile strength that depicted a decreasing trend with increasing weight fraction of the reinforcing filler, in a manner similar to that of the experimental results obtained here. Nielsen’s equation gave rise to predicted values of percentage elongation that were much less than the experimental results obtained in the present work. Einstein’s and Voigt equations predicted values of tensile stiffness that were higher than the experimental values obtained here, whilst the Reuss equation predicted values that were lower than these experimental values. The model of Guth and separately Smallwood predicted values that were closest to the experimental values obtained here

A Review of Methods Used to Determine the Overall Stiffness of Unitary Automotive Body Structures

ArticleA review of the methods that are used to determine the overall stiffness of automotive body structures was conducted. The review showed that the overall stiffness of body structures is affected by the geometry of the body structure as well as the material used to build the body structure. However, only a limited amount of literature was found that demonstrated how the stiffness behaviour of the body structure is affected by the change in geometry or material. It was also found that the deformation and applied load are directly proportional for body structures that are deformed within the elastic range. However, most of the studies have demonstrated this occurrence by considering the loads that are way less than the approximate, real-life running loads. Therefore, there is a need to study the effects of different materials as well as different geometries on the overall stiffness of body structures when considering the approximate real-life load cases, particularly during the early stages of the development of new vehicle body structures

A Review Of The State Of Research And Utilization Of Biomaterials In The Manufacture Of Composite Materials Todate

ArticleOver the last four decades composite materials, plastics and ceramics have been the dominant emerging materials. The volume and number of applications of composite materials has grown steadily, penetrating and gaining acceptance in new markets. Modern composite materials constitute a significant proportion of the engineered materials market, ranging from everyday products to sophisticated niche applications. While composites have already proven their worth as weight saving materials, the current challenge is to make them cost effective. This paper presents review on the worldwide state of research of biomaterials and their utilization in the manufacture of composite materials

A convenient band-gap interpolation technique and an improved band line-up model for InGaAlAs on InP

The band-gap energy and the band line-up of InGaAlAs quaternary compound material on InP are essential information for the theoretical study of physical properties and the design of optoelectronics devices operating in the long-wavelength communication window. The band-gap interpolation of In1-x-y Ga (x) Al (y) As on InP is known to be a challenging task due to the observed discrepancy of experimental results arising from the bowing effect. Besides, the band line-up results of In1-x-y Ga (x) Al (y) As on InP based on previously reported models have limited success by far. In this work, we propose an interpolation solution using the single-variable surface bowing estimation interpolation method for the fitting of experimentally measured In1-x-y Ga (x) Al (y) As band-gap data with various degree of bowing using the same set of input parameters. The suggested solution provides an easier and more physically interpretable way to determine not only lattice matched, but also strained band-gap energy of In1-x-y Ga (x) Al (y) As on InP based on the experimental results. Interpolated results from this convenient method show a more favourable match to multiple independent experiment data sets measured under different temperature conditions as compared to those obtained from the commonly used weighted-sum approach. On top of that, extended framework of the model-solid theory for the band line-up of In1-x-y Ga (x) Al (y) As/InP heterostructure is proposed. Our model-solid theory band line-up result using the proposed extended framework has shown an improved accuracy over those without the extension. In contrast to some previously reported works, it is worth noting that the band line-up result based on our proposed extended model-solid theory has also shown to be more accurate than those given by Harrison's mode

VR open scores: scores as inspiration for VR scenarios

In this paper, we introduce the concept of VR Open Scores: aleatoric score-based virtual scenarios where an aleatoric score is embedded in a virtual environment. This idea builds upon the notion of graphic scores and composed in- strument, and apply them in a new context. Our proposal also explores possible parallels between open meaning in interaction design, and aleatoric score, conceptualized as Open Work by the Italian philosopher Umberto Eco. Our approach has two aims. The first aim is to create an envi- ronment where users can immerse themselves in the visual elements of a score while listening to the corresponding mu- sic. The second aim is to facilitate users to develop a per- sonal relationship with both the system and the score. To achieve those aims, as a practical implementation of our proposed concept, we developed two immersive scenarios: a 360o video and an interactive space. We conclude pre- senting how our design aims were accomplished in the two scenarios, and describing positive and negative elements of our implementations

Diffusion of Zn into GaAs and AlGaAs from isothermal Liquid-phase epitaxy solutions

In this work we present results of zinc diffusion in GaAs using the liquid phase epitaxy technique from liquid solutions of Ga‐As‐Zn and Ga‐As‐Al‐Zn. Using silicon‐doped n‐GaAs substrates, working at a diffusion temperature of 850 °C, and introducing a dopant concentration ranging 1018–1019 cm−3, the most important findings regarding the diffusion properties are as follows: (a) zinc concentration in the solid depends on the square root of zinc atomic fraction in the liquid; (b) the diffusion is dominated by the interstitial‐substitutional process; (c) the diffusivity D varies as about C3 in the form D=2.9×10−67C3.05; (d) aluminum plays the role of the catalyst of the diffusion process, if it is introduced in the liquid solution, since it is found that D varies as (γAsXlAs)−1; (e) the zinc interstitial is mainly doubly ionized (Zn++i); (f) the zinc diffusion coefficient in Al0.85 Ga0.15 As is about four times greater than in GaAs; (g) by means of all these results, it is possible to control zinc diffusion processes in order to obtain optimized depth junctions and doping levels in semiconductor device fabrication