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A Flow Injection Immunosensor for the Detection of Atrazine in Water Samples
No full textQuantification of atrazine in a sample was performed using a post-reactive column consisting rabbit anti-immunoglobulin G for trapping atrazine specific antibodies bound to antigen and tracer. The assay is based on a competitive enzyme immunoassay where the analyte and known amount of tracer (peroxidase labeled hapten) bind competitively to available sites of anti-atrazine
antibodies. The absorbance signal, proportional to the amount of antigen present, is generated with the
unbound tracer passing through the column, and monitored continuously with a spectrophotometer. Several parameters which affect the immunosensor response were evaluated, including the flow rate through the column, stability of enzyme tracer in the column, for increasing the sensitivity of the system. The immunosensor has a detection limit of 1 ng/ml with good signal precision app. 2 % in the optimum working concentration range between 1 – 100 ng/ ml of atrazine in standard water sample
Performance Evaluation of a Novel iTongue for Indian Black Tea Discrimination
No full textIn this work, the multi-electrode-single-frequency
(MESF), multi-frequency-single-electrode (MFSE), and multi-frequency-
multi-electrode (MFME) impedance responses of an
impedance-Tongue reported previously, are evaluated for their
discriminability of Indian Black Teas. Principal component
analysis (PCA) in conjunction with a cluster validity measure,
Davis–Bouldin Index (DBI), has been used for discriminability
evaluation. The discriminabilities of electrode specific frequency
segments chosen by optimization algorithms, namely, Genetic
Algorithm (GA) and Particle Swarm Optimization (PSO) have
also been evaluated. The results show that the MFSE impedance
response of Gold electrode gives the best discriminability without
compromising the system complexity as against MESF, MFSE,
MFME, and GA/PSO-optimized response. The results also suggest
that the cross-sensitivity of electrodes may be enhanced by
selecting optimum frequencies and/or electrodes, paralleling the
practice of modifying the electrodes. This opens up a new approach
towards qualitative and quantitative analysis of complex
liquids
Tunable wavelength division multiplexing channel isolation filter based on dual chirped long-period fiber gratings
No full textWe propose and demonstrate a wavelength tunable wavelength division multiplexing channel isolation filter based on two concatenated chirped long-period fiber gratings (LPGs). An intergrating space (IGS), deliberately introduced between the two gratings, provides an extra phase difference between the core and cladding modes. Changing this phase by heating the IGS without affecting the gratings tunes the channels. A theoretical account of the filter action is also presented and the results are found to be in excellent agreement with the experiments. Unlike the filters based on normal concatenated chirped LPGs without an IGS, the current filter shows a linear tuning over an increased spectral range
A novel approach using Dynamic Social Impact Theory for optimization of impedance-Tongue (iTongue)
No full textThis paper presents a novel multiobjective wrapper approach using Dynamic Social Impact Theory based optimizer (SITO). A Fuzzy Inference System in conjunction with support vector machines classifier has been used for the optimization of an impedance-Tongue for the classification of samples collected from single batch production of Kangra orthodox black tea. Impedance spectra of the tea samples have been measured in the range of 20 Hz to 1 MHz using a two electrode setup employing platinum and gold electrodes. The proposed approach has been compared, for its robustness and validity using various intra and inter measures, against Genetic Algorithm and binary Particle Swarm Optimization. Feature subset selection methods based on the first and second order statistics have also been employed for comparisons. The proposed approach outperforms the Genetic Algorithm and binary Particle Swarm Optimization
Single Electron Effects In DNA Bases
No full textThe reducing sizes of electron devices are also reducing the magnitude of current flow through the devices. The Single electron devices are nanoelectronic devices that can be used to control and manipulate flow of a single electron. Coulomb blockade is a typical single electron phenomenon. In this paper the molecular energy levels of DNA base molecules Adenine, Thymine, Guanine and Cytosine are studied to predict their suitability for use in room temperature single electron devices. The charging
energy of molecules is indicated by the energy gap between the HOMO and LUMO called HOMO-LUMO gap (HLG). The
energy of molecular orbitals are calculated by Hartree Fock method using STO-3G basis set in Gaussian 03 program for the four bases of DNA. It was found that all the four base molecules have HLG’s larger than the thermal energy at room temperature. The energy levels were also calculated for the anionic and cationic forms of the DNA bases. It is observed that there is formation of Coulomb blockade on anionic bases and a Coulomb well on cationic bases
Performance evaluation of digital grain moisture analyser for Indian wheat
Get PDFThis study presents an inexpensive and portable micro-controller based digital grain moisture analyser (DGMA) for Indian wheat. A prediction model has been devised to readily calculate and display moisture (%) on digital readout. A good co-relation wasfound between moisture values of Indian wheat compared with moisture values for same grain with standard dry oven method.High values of coefficient of correlation under all plotted graphs indicate high accuracy of DGM
Reflective Properties Of Zns Nanoparticle Coatings
No full textIn the present paper, the authors report
having developed highly reflective and durable coatings
using synthesized zinc sulfide-capped thioglycerol
nanoparticles. The coating material was prepared by
dispersing ZnS/thioglycerol nanoparticles in an acrylic
binder. The light reflectors were made applying this
coating material to an aluminum substrate; their
diffuse reflectance was measured and found to vary
from 97% to 100% for 0.30-mm thick coating having
14% pigment-to-binder ratio. The aging effect of the
reflectors with respect to temperature and illumination
was also investigated to check their durability and they
have been found to be optically stable up to 10,000 lux,
and thermally up to 80°C
Automatic Craniofacial Structure Detection on Cephalometric Images
No full textAnatomical structure tracing on cephalograms is a significant way to obtain cephalometric analysis. Cephalometric analysis is divided in two categories, manual and automatic approaches. The manual approach is limited in accuracy and repeatability due to differences in inter- and intra-personal marking. In this paper, we have attempted to develop and test a novel method for automatic localization of craniofacial structures based on the detected edges in the region of interest. Before edge detection of the particular region, the region was filtered by adaptive non local filter for noise removal by keeping the edge information undisturbed. According to the gray-scale feature at the different regions of the cephalograms, modified Canny edge detection algorithm for obtaining tissue contour was proposed. With the application of morphological opening and edge linking approaches, an improved bidirectional contour tracing methodology was proposed by an interactive selection of the starting edge pixels, the tracking process searches repetitively for an edge pixel at the neighborhood of previously searched edge pixel to segment images, and then craniofacial structures are obtained. The effectiveness of the algorithm is demonstrated by the preliminary experimental results obtained with the proposed method
Evaluation of calibration of moisture meter for Indian wheat by microwave oven drying technique and commercial moisture meter
No full textMoisture plays an important role in storage and processing of food grains, cereals and other agricultural products. It is the single most important characteristics of most agricultural products with respect to quality maintenance. This paper describes how to prepare samples for moisture determination, and calibrate a moisture meter for a particular grain. Calibration of a laboratory-developed moisture meter (LDMM) with a a commercial moisture meter (CMM) is also presented in this paper, in order to evaluate its performance. It shows that the values estimated by the LDMM were in good agreement with the moisture content values that are obtained by CMM, and the developed meter has a less than�1% error. It also describes the
studies carried out for calibration of the LDMM using a microwave oven drying technique. An evaluation of the calibration performance of LDMM with two different techniques has also been reported. The microwave oven method and dry oven method have been compared for moisture determination of Indian wheat. It has been observed that the microwave method took 10–20 min compared with 18–20 h by the standard dry oven method for moisture determination of Indian wheat. The results obtained by the microwave oven method were compared with those obtained by the dry oven
method. No statistical difference was observed between the percentage moisture values of Indian wheat samples by microwave drying and dry oven drying. The accuracy of the developed meter has also been tested by taking different numbers of calibration samples. It was observed that the accuracy increased considerably with an increase in the number of calibration sample
Improvement in the luminous efficiency of MEH-PPV based light emitting diodes using zinc oxide nanorods grown by the electrochemical deposition technique on ITO substrates
No full textZinc oxide (ZnO) nanorods grown by the electrochemical technique have been used to enhance the luminance of poly[2-methoxy-5-(2'-ethylhexoxy)-1,4-phenylenevinylene] (MEH-PPV)-based polymer light-emitting diodes. The luminance of the device with ZnO nanorods is found to increase by more than two times as compared with the device without ZnO nanorods. The diameter of the nanorods used in device fabrication was ~145 nm. The size of the nanorods was estimated from field emission scanning electron microscope images. Optical and structural characterizations of the nanorods were also performed by using absorption, photoluminescence and x-ray diffraction, confirming the formation of ZnO nanorods