92 research outputs found
Ascorbyl palmitate synthesis in an organic solvent system using a Celite-immobilized commercial lipase (Lipolase 100L)
Multi-objective optimization of Nd: YAG laser cutting parameters based on BBD-SA hybrid approach
295-300This paper presents a Box-Behnken Design (BBD)-Simulated Annealing (SA) hybrid approach to process parameter optimization for Nd:YAG laser cutting in Ti-6Al-4V super alloy sheet. Pulse width, pulse energy, cutting speed and gas pressure are considered the dominant input process parameters whilst the kerf deviation and material removal rate are the responses. The adequacy and significance of developed models are verified by ANOVA analysis. Further, the optimization of pulsed Nd: YAG laser cutting process parameters is carried out by a feasible approach of simulated annealing (SA) algorithm to maximize the material removal rate (MRR) and minimizing of kerf deviation (KD) simultaneously. Experimental results show that the proposed approach is both effective and efficient
Research Article Modeling and Multi-response Optimization of Hard Milling Process using Desirability Function Approach
Abstract: The characteristic features of hard milling are variable chip thickness and intermittent cutting. Such tendency rapidly increases the tool wear and reduces the metal removal rate against the cutting temperature results poor surface finish. Therefore, the objective of this present study was to present the mathematical models for modeling and analysis on the effects of process parameters, including the feed per tooth, radial depth of cut, axial depth of cut and cutting speed on cutting temperature, tool wear and metal removal rate in hard milling of 100MnCrW4 (Type O1) tool steel using (TiN+TiAlN) coated carbide inserts. A central composite rotatable design with four factors and five levels was chosen to minimize the number of experimental conditions. Further, the reduced developed models were used for multiple-response optimization by desirability function approach in order to determine the optimum cutting parameters. These optimized machining parameters are validated experimentally and the experimental and predicted values were in a good agreement with small consistent error
International Journal of Innovative Trends and Emerging Technologies ROBUST SCAN TECHNIQUE FOR SECURED AES AGAINST DIFFERENTIAL CRYPTANALYSIS BASED SIDE CHANNEL ATTACK
Abstract: The proposed is a scan-protection scheme that provides testing facilities both at production time and over the course of the circuit"s life. The underlying principle is to scan-in both input vectors and expected responses and to compare expected and actual responses within the circuit. This scheme avoids the use of authentication tests. The proposed scan-protection scheme for the most secured cryptographic algorithm (AES Algorithm) to implement on any hardware with BIST architecture. This proposed method uses a Robust Scan Flip-Flops (RSFF) that delivers different outputs state for the same scan input. Thus the technique is unsusceptible to side channel attacks that hackers use to easily scan the encryption/decryption key and algorithm implementation
Parametric optimisation in Nd-YAG laser cutting of thin Ti-6Al-4V super alloy sheet using evolutionary algorithms
Salt effect on the enthalpy of mixing of 2-propanol + acetic acid at 303.15 K
This paper presents the effect of two dissolved inorganic salts (zinc chloride, ZnCl2 and ammonium chloride, NH4Cl) on the enthalpy of mixing (HE) of 2-propanol + acetic acid binary system measured at 303.15 K using an isothermal displacement calorimeter with vapour space. A decreasing trend in the excess enthalpy of mixing values in the presence of ZnCl2 and NH4Cl indicate the endothermic behavior of this system. The Redlich-Kister equation has been used to fit the experimental HE data. The deviations from the ideal value and binary parameters were calculated and reported
Salt effect on the enthalpy of mixing of 2-propanol + acetic acid at 303.15 K
This paper presents the effect of two dissolved inorganic salts (zinc chloride, ZnCl2 and ammonium chloride, NH4Cl) on the enthalpy of mixing (HE) of 2-propanol + acetic acid binary system measured at 303.15 K using an isothermal displacement calorimeter with vapour space. A decreasing trend in the excess enthalpy of mixing values in the presence of ZnCl2 and NH4Cl indicate the endothermic behavior of this system. The Redlich-Kister equation has been used to fit the experimental HE data. The deviations from the ideal value and binary parameters were calculated and reported
Engineered Two-Dimensional Nanostructures as SERS Substrates for Biomolecule Sensing: A Review
Two-dimensional nanostructures (2DNS) attract tremendous interest and have emerged as potential materials for a variety of applications, including biomolecule sensing, due to their high surface-to-volume ratio, tuneable optical and electronic properties. Advancements in the engineering of 2DNS and associated technologies have opened up new opportunities. Surface-enhanced Raman scattering (SERS) is a rapid, highly sensitive, non-destructive analytical technique with exceptional signal amplification potential. Several structurally and chemically engineered 2DNS with added advantages (e.g., π–π* interaction), over plasmonic SERS substrates, have been developed specifically towards biomolecule sensing in a complex matrix, such as biological fluids. This review focuses on the recent developments of 2DNS-SERS substrates for biomolecule sensor applications. The recent advancements in engineered 2DNS, particularly for SERS substrates, have been systematically surveyed. In SERS substrates, 2DNS are used as either a standalone signal enhancer or as support for the dispersion of plasmonic nanostructures. The current challenges and future opportunities in this synergetic combination have also been discussed. Given the prospects in the design and preparation of newer 2DNS, this review can give a critical view on the current status, challenges and opportunities to extrapolate their applications in biomolecule detection
Functionalised activated carbon modified polyphenylsulfone composite membranes for adsorption enhanced phenol filtration
BACKGROUND: Functionalized activated carbon (FAC) was prepared by immobilizing the activated carbon (AC) synthesized from Acacia fumosa seeds in cacium-alginate beads. Synthesized FAC has been blended with polyphenylsulfone (PPSU) in the composition of 0.25 to 1wt% with an increment of 0.25wt% to prepare composite membranes of PPSU/FAC by wet phase inversion method. The existence of FAC in PPSU was confirmed by Fourier transform infra-red spectroscopy (FTIR) studies by the presence of characteristic functional groups of FAC. The influence of FAC on adsorption enhanced rejection of phenol during membrane filtration has been investigated. RESULTS: The hydrophilicity of PPSU/FAC composite membranes has been improved by FAC as there was a profound reduction in contact angle from 71.8° to 43.8°. With the minimum loading of 0.25wt% of FAC in PPSU, the maximum adsorption of phenol has taken place suggesting that the better dispersion of minimal loading will offer higher accessibility to adsorptive sites. CONCLUSIONS: The adsorption of phenol on FAC was observed to be higher in PPSU/FAC composite membranes when compared with FAC being used solely as an adsorbent
A critical review of carbon nanotube-based surface coatings
The emergence of carbon nanotubes (CNT) has encouraged widespread interest among researchers with many pioneering applications achieved by exploiting the unique properties of carbon allotropes. This article is a general overview of the diversity of applications of CNT and their various forms, particularly, in the area of surface coatings. The different methods, which have been developed and practiced in the preparation, dispersion, functionalization, and metallization of CNT, are elucidated. The composite coatings have been prepared using electrochemical methods such as electroplating and electroless plating. The review presents the mechanical, electrochemical, corrosion, thermal, electrical conduction, tribological, biosensing, magnetic, and microwave absorbing properties of CNT-based composites. The incorporation of CNT substantially affects the coating performance, and the level of influence can be befittingly adjusted to suit the application needs. Various charac terization studies have been conducted on these coatings, emphasizing their properties. The potential of CNT as a versatile material in catering to diverse industrial applications has placed the carbon allotrope among the elite group of materials, drawing the attention of researchers to widen their scope of utilization. The challenges, problems, and ways of the overcoming are also addressed in this review.</p
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