654 research outputs found
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Conjugation of nano and quantum materials with bovine serum albumin (BSA) to study their biological potential
No full textConjugates of gold nanoparticles (AuNPs) and semiconductor quantum dots (CdS/T) have been synthesized with bovine serum albumin (BSA) using wet chemistry. The optical properties of nano and quantum materials and their BSA conjugate have been studied using UV–Visible and Fluorescence spectroscopy. UV–Visible spectrum of pure BSA showed an absorption maximum at 278 nm, which showed blue shift after its conjugation with nano and quantum materials. Increased concentration of AuNPs during conjugation resulted in broadening of BSA peak (278 nm), which can be related to the formation of ground state complex formation, caused by the partial adsorption of BSA on the surface of NPs. However, increased concentrations of BSA resulted in decrease in SPR intensity of gold nanoparticles (528 nm) and absorbance peak of BSA started diminishing. AuNPs acted as quencher for BSA fluorescence intensity, when excited at 280 nm. The binding constant (K) and the number of binding sites (n) between AuNPs and BSA have been found to be 1.97×102 LM−1 and 0.6 respectively. With quantum dots, conjugation resulted in enhancement of fluorescence emission of quantum dots when excited at 300 nm, which might be due to the stabilizing effect of BSA on QDs or due to energy transfer from tryptophan moieties of albumin to quantum dots
Discrimination analysis of Indian tea varieties based upon color under optimum illumination.
No full textThe paper investigates optimum light illumination intensity for maximum discrimination of the Indian black tea varieties using machine vision. The technique involves acquisition and analysis of color information of brewed tea liquor after setting different light illumination intensities between 700 and 1,300 lux. The data involving color attributes was analyzed using principal component analysis. It was observed that best discrimination among these tea varieties was achieved between 1,000 and 1,050 lux. The correlation analysis was also performed to show the relationship between color attributes and tea varieties. The study reveals that color attributes are significant parameters for discriminating Indian black tea varieties. The proposed technique is fast, convenient and low cost over the methods involving chemical analysis. It is an important step towards standardization of quality evaluation of tea by instrumented means
Design Analysis of Variable Damping Mechanism Using Magnetorheological Fluids for Adaptive Prosthetic Foot
No full textThe applications of Magnetorheological (MR) fluids to act as mechanical dampers are new and increasing day by day. This paper proves to be an attempt in applying variable damping properties of a MR fluid in a new application of adaptive variable damper prosthetic foot. A 3-D model of the prosthetic foot was developed on the software Autodesk Inventor Professional 2011. Design analysis of prosthetic foot was carried out and damping coefficients were calculated with the help of Dynamic Simulation Environment of Inventor. Typical specification of MR fluid was suggested to act as damper for the prosthetic foot
Current status of electrostatic spraying technology for efficient crop protection
No full textPesticide application to protect crops against diseases and pests is an integral part of modern farming. Electrostatic spraying of pesticides improves not only the deposition efficiency but also the spatial distribution of deposited droplets throughout the plant canopy, particularly under leaf application where pests usually hide and reside. A review of current status in the field of electrostatic spraying technology for agricultural applications is presented in this paper. Current results of research conducted on the electrostatic spraying, charging methods, induction parameters, sprayer testing, and bio-efficacy have been presented. Research findings on the induction charging method, charge to mass ratio, air flow speed, electrode radius and distance from nozzle, voltage, spray distribution pattern, spray deposition, image analysis and drift losses are summarized in this review. It is found that induction charging is the most widely used method, as the high voltage for particle charging does not directly contact the liquid, the electric field strength is below the breakdown strength of the air, its working voltage is relatively low, and electrode insulation is easier. The high charging voltage leads to high charge to mass ratio and higher underside deposits. The average deposit does not increase with the charging voltage. The charging factor increases first and then decreases or remains unchanged with the increasing distance between electrode and nozzle. The use of machine vision combined with image analysis is considered to increase speed, ease of use and to reduce the cost of spray deposition assessment. With the electrostatic spraying, the mortality of pests is also higher than non-electrostatic spraying. Reducing spray volume from 250 1/ha to 1 1/ha does not change bio-efficacy in the electrostatic spraying
A brief overview of population - based optimization techniques and their applications post 2011
No full textNaturally occurring phenomenon serves as an unbiased guide for solving various optimization problems . This paper compiles some of the population - based, sto chastic optimization algorithms including the recently developed social impact theory based optimizer , SITO . The current state of research , including the natural phenomena followed by each and some of their applications to solve various optimization problems is illustrated . The applications after the year 2011 are covered. The efficiency and robustness of various algorithms explored herein , includes particle swarm optimization (PSO) , harmony search (HS) and social impact theory based optimizer (SITO)
Numerical Study on the Performance of Double Layer Microchannel with Liquid Gallium and Water
No full textThe performance of liquid gallium and water in the double layer microchannel has been analysed using three-dimensional conjugate heat transfer analysis. The effect of flow rate on the counter and parallel arrangement of each fluid is studied for three different lengths. Furthermore, cooling capability of liquid gallium and water is compared at the same length with flow rate and pumping power as governing parameters. The performance of fluid was judged on the basis of maximum temperature attained and minimal temperature variations at the heated region. Interesting results have been found showing the effect of specific heat on the type of arrangement for liquid gallium with similar observation for water for low Reynolds number and relatively longer length. Among liquid gallium and water, above certain pumping power use of liquid gallium is found to be favourable for a shorter length of the double layer microchannel. Furthermore, the range of flow rate and pumping power showing superior performance with water was found to increase with the length
Characterization of electrode material for electrostatic spray charging: Theoretical and engineering practices
No full textA new electrode material such as Nickel (200/201 forged bar) is used for spray charging. Comparative study has been made using different materials electrode viz. Nickel, Copper, Stainless Steel, Brass, and Aluminum; electrodes were ring shape with same inner diameter 15.0 mm and outer diameter of 22.0 mm of thickness 3.5 mm. The experiments were conducted in air atmosphere at ambient conditions (T = 20 ± 2 °C, RH = 46 ± 3%), with an air feed rate of 24.6 l/min, liquid feed rate 90.0 ml/min and applied voltage ranging from 0 to +3.0 kV. The results of applied induction electrification process were characterized by a charge-to-mass factor as a function of electrode material
Thermal and electrical behavior of silver chloride/polyaniline nanocomposite synthesized in aqueous medium using hydrogen peroxide
No full textNanocomposites of AgCl/PANI were synthesized by chemical polymerization/precipitation in aqueous HCl solution using both aniline monomer and AgNO3 precursors in different molar ratio in PVP. Silver ions interact with PVP which restrict the bulk growth of AgCl and keep it in nanosized. During synthesis, AgCl NPs got entrapped in PANI chains through inter-chain hydrogen bonding. TGA studies showed complete decomposition of polymer chains occurred at 30–40 °C higher temperature than PANI alone. DSC studies indicate higher thermal stability of the composite, which is due to more heat flow for decomposition of polymer chains indicating compact packing of polymer matrix with AgCl NPs having large surface area to volume ratio. The TEM image showed spherical NPs were randomly dispersed in a polymer matrix and from XRD data crystalline nature of composite was seen. In FT-IR spectrum strong absorption band of a carbonyl stretching group due to PVP indicates its presence on nanoparticle surface in composite. Thin films of nanocomposite were spin casted on ITO coated glass surface. Electrical conductance was calculated from I–V data which was found to be in the range of 10−2–10−7 S cm−1 depending on the concentration of NPs in it. These composites may find applications in solar cells as semiconductor material and for designing multiarray sensors for quality interpretation of beverages on the basis of their conductance changes using soft computing technique
Optimized butt coupling between single mode fiber and hollow-core photonic crystal fiber
No full textn this paper, the optimum gap for maximum light coupling between Single Mode Fiber (SMF) & Hollow Core Photonic Crystal Fiber (HC-PCF) is theoretically computed and experimentally demonstrated. The Gaussian beam profile emanating from transmitting fiber undergoes Fresnel diffraction in the air up to some distance till its diffracted Mode Field Diameter (MFD) matches with the core diameter of receiving fiber. Theoretically computed such distance provides an optimum gap for maximum light coupling between these two fibers. The optimum gap is numerically computed as 7.618 μm and 12.598 μm for SMF to HC-PCF and HC-PCF to SMF light transmission configurations respectively and is verified experimentally. This optimized gap is useful for HC-PCF based devices to be joined to SMF as a transmission medium
Patient-Wise Versus Nodule-Wise Classification of Annotated Pulmonary Nodules using Pathologically Confirmed Cases
No full textThis paper presents a novel framework for combining well known shape, texture, size and resolution informatics descriptor of solitary pulmonary nodules (SPNs) detected using CT scan. The proposed methodology evaluates the performance of classifier in differentiating benign, malignant as well as metastasis SPNs with 246 chests CT scan of patients. Both patient-wise as well as nodule-wise available diagnostic report of 80 patients was used in differentiating the SPNs and the results were compared. For patient-wise data, generated a model with efficiency of 62.55% with labeled nodules and using semi-supervised approach, labels of rest of the unknown nodules were predicted and finally classification accuracy of 82.32% is achieved with all labeled nodules. For nodule-wise data, ground truth database of labeled nodules is expanded from a very small ground truth using content based image retrieval CBIR) method and achieved a precision of 98%. Proposed methodology not only avoids unnecessary biopsies but also efficiently label unknown nodules using pre-diagnosed cases which can certainly help the physicians in diagnosis