Effect of MQL and nanofluid on the machinability aspects of hardened alloy steel

Abstract

The current research comprises of various machinability aspects of 4340 hardened alloy steel which are scrutinized with in context of improvements in main cutting force, tool flank wear, crater wear, surface roughness, micro-hardness, machined surface morphology, chip morphology, chip reduction coefficient and apparent coefficient of friction under three different cutting fluid applications i.e. compressed air, water soluble coolant and nanofluid (using eco-friendly radiator coolant as the base fluid and Al₂O₃ as the nanoparticle) using uncoated cermet cutting inserts and a comparative assessment was performed to select which fluid performed better in terms of various machining attributes among three cutting fluids. The minimum quantity lubrication technique (MQL) was used in which a smaller volume of coolant sprinkled at high pressure. This method is found as the most effective alternative to minimize health risks and machining costs, which is quite high in other setups. The test specimen was machined at three different cutting speeds i.e. 100, 120 and 140?m/min along with two machining parameters i.e. feed and depth of cut were kept constant respectively at 0.2?mm/rev and 0.4?mm. Outcomes made a conclusion that Al₂O₃ enriched ecofriendly nanocoolant outperformed both compressed air and water soluble coolant in terms of every machinability aspects.     

Antifungal activity of five different essential oils in vapour phase for the control of Colletotrichum gloeosporioides and Lasiodiplodia theobromae in vitro and on mango

Mango fruit has high commercial value; however, major postharvest losses are encountered throughout the supply chain due to postharvest diseases. These results lead to the search for natural fungicide for postharvest diseases control. The antifungal effects of five essential oils (thyme, clove, cinnamon, anise and vitex) were assessed by disc volatilisation method. Thyme oil vapours at 5 μL per Petriplate, and clove and cinnamon oil at 8 μL per Petriplate showed 100% growth inhibition of mango pathogens in vitro. GC/MS analysis of essential oil showed thymol (23.88), o‐cymol (23.88) and terpinolene (23.88) as the major constituents of thyme oil. Clove and cinnamon oils contain 3‐allyl‐2‐methoxyphenol (37.42%) and benzofuran 3‐methyl (17.97%), respectively. Thyme oil as a fumigant at 66.7 μL L^?1 showed a significant (P < 0.05) inhibition on postharvest pathogens of mango fruits stored at 25 °C for 6 days. Results of our study suggest the possibility of using thyme oil as an alternate natural fungicide to manage postharvest diseases in mango.     

Status Report on Women and Men in the IT Workplace

A profile of women and men in the IT field along personal, family, job, and career-related variables has broad implications for the placement, development, promotion, and retention of women IT professionals. Among the study's major findings is that impressive gains in employment have not increased the numbers of women holding managerial positions nor resolved the work/life conflicts, lower salaries, and incompatibility between career orientation and job tasks experienced by women in the IT field.     

Optimal Temperature Tracking for Accelerated Cooling Processes in Hot Rolling of Steel

This paper is concerned with the development of a control system for tracking of a desired temperature-time profile for accelerated cooling processes in hot rolling of steel. Control of temperature during cooling is essential for achieving desired mechanical and metallurgical properties of steel. The cooling process is represented by the heat equation in Lagrangian coordinates which is approximated by a set of ordinary differential equations. The control variable is the velocity of coolant water flow. Motivated by the fact that in many steel industries water flow is adjusted to some fixed velocity based on experience and heuristics, we assume that the control variable, water jet velocity, be a constant time invariant parameter. Gamkrelidze minimum principle is used to determine the optimal jet velocity for the desired temperature tracking. The results are illustrated by simulation examples.     

Fuzzy least squares twin support vector clustering

In this paper, we have formulated a fuzzy least squares version of recently proposed clustering method, namely twin support vector clustering (TWSVC). Here, a fuzzy membership value of each data pattern to different cluster is optimized and is further used for assigning each data pattern to one or other cluster. The formulation leads to finding k cluster center planes by solving modified primal problem of TWSVC, instead of the dual problem usually solved. We show that the solution of the proposed algorithm reduces to solving a series of system of linear equations as opposed to solving series of quadratic programming problems along with system of linear equations as in TWSVC. The experimental results on several publicly available datasets show that the proposed fuzzy least squares twin support vector clustering (F-LS-TWSVC) achieves comparable clustering accuracy to that of TWSVC with comparatively lesser computational time. Further, we have given an application of F-LS-TWSVC for segmentation of color images.

     

Robust Parametric Twin Support Vector Machine for Pattern Classification

In this paper, we propose a robust parametric twin support vector machine (RPTWSVM) classifier based on Parametric-\(\nu \)-Support Vector Machine (Par-\(\nu \)-SVM) and twin support vector machine. In order to capture heteroscedastic noise present in the training data, RPTWSVM finds a pair of parametric margin hyperplanes that automatically adjusts the parametric insensitive margin to incorporate the structural information of data. The proposed model of RPTWSVM is not only useful in controlling the heteroscedastic noise but also has much faster training speed when compared to Par-\(\nu \)-SVM. Experimental results on several machine learning benchmark datasets show the advantages of RPTWSVM both in terms of generalization ability and training speed over other related models.     

Viscometric studies: Interpolymer complex formation between poly(styrene-b-ethylene oxide) block copolymers and poly(acrylic acid)

Summary Interpolymer complex formation between poly(styrene-b-ethylene oxide) block copolymers (PS-PEO) and poly(acrylic acid) (PAA) has been studied by viscometry using THF-water mixture of several compositions as solvent.Unlike alternating and random copolymers, composition of the complex formed between (PS-PEO) and PAA does not seem to be affected by the molecular characteristics of the copolymer and the solvent composition. However the nature of the reduced viscosity curves during complex formation was found to be dependent on solvent composition and this has been interpreted in terms of preferential solvation, conformation and micellization of the block copolymer molecules.     

Enhanced In Vitro Percutaneous Absorption and In Vivo Anti-Inflammatory Effect of a Selective Cyclooxygenase Inhibitor Using Microemulsion

Celecoxib, a specific COX-2 inhibitor, was recently approved for the treatment of rheumatoid and osteoarthritis, acute pain, familial adenomatous polyposis and primary dysmenorrhea. Oral administration of celecoxib is effective against ultraviolet B radiation (UVB)-induced skin carcinogenesis; however, its clinical use is restricted because of its failure to block the characteristic cutaneous inflammatory response and lower availability at the site of inflammation. Topical application of celecoxib has been effective compared with oral in certain clinical conditions. The present study was undertaken to develop and investigate the development of microemulsion system (isopropyl myristate/medium-chain glyceride/polysorbate 80/water) for topical delivery of celecoxib. The pseudoternary phase diagram was constructed with constant surfactant concentration, and several compositions were identified and characterized by using dynamic light scattering. The in vitro permeation rate of celecoxib through rat skin was determined for microemulsions, microemulsion gel, and cream by using the modified Franz-type diffusion cell. In all formulations tested, celecoxib permeated more quickly, and the microemulsions increased the permeation rate of celecoxib up to 5 and 11 times compared with those of microemulsion gel and cream, respectively. Increasing the concentration of medium-chain mono-/di-glyceride in microemulsion imparted increased droplet size and viscosity and decreased diffusion coefficient. In vivo anti-inflammatory study suggested that the developed microemulsion formulations might serve as potential drug vehicle for the prevention of UVB-induced skin cancer.