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Ultrafine Fiber Tip Etched in Hydrophobic Polymer Coated Tube for Near-Field Scanning Plasmonic Probe
No full textWe propose a novel one-step etching technique for the
preparation of an optical fiber tip using a hydrophobic polymer coated tube (HP) containing 48% hydrofluoric acid (HF) to etch photosensitive single-mode fiber (PSMF). Dipping of PSMF in an HP tube suppresses the convex meniscus (CM) of the HF solution in the tube due to formation of a concave surface tension meniscus
(SM) around the PSMF. The continuous etching reduces the
diameter of PSMF and shortens the SM along PSMF resulting
in elevation of CM around PSMF. The elevation of the CM and
faster etching rate of the PSMF core digs a capillary ring along the fiber core-cladding boundary. Capillary action fills the ring with HF, which finally recedes and creates a tip at the apex of the fiber. We have fabricated a typical tip with typical features of tip height m, base diameter m, cone angle , and aperture nm. For the theoretical analysis, a tip similar to the fabricated one is modeled to estimate surface plasmon (SP)enhancement, , at the end of the tip with a silver coating
AN APPLICATION OF HYBRID CLUSTERING AND NEURAL BASED PREDICTION MODELLING FOR DELINEATION OF MANAGEMENT ZONES
No full textStarting from descriptive data on crop yield and various other properties, the aim of this study is to reveal the trends on soil behaviour, such as crop yield. This study has been carried out by developing web application that uses a well known technique- Cluster Analysis. The cluster analysis revealed linkages between soil classes for the same field as well as between different fields, which can be partly assigned to crops rotation and determination of variable soil input rates. A hybrid clustering algorithm has been developed taking into account the traits of two clustering technologies: i) Hierarchical clustering, ii) K-means clustering. This hybrid clustering algorithm is
applied to sensor- gathered data about soil and analysed, resulting in the formation of well delineated management zones based on various properties of soil, such as, ECa , crop yield, etc. One of the purposes of the study was to identify the main factors affecting the crop yield and the results obtained were validated with existing techniques. To accomplish this purpose, geo-referenced soil information has been examined. Also, based on this data, statistical method has been used to classify and
characterize the soil behaviour. This is done using a prediction model, developed to predict the unknown
behaviour of clusters based on the known behaviour of other clusters. In predictive modeling, data has
been collected for the relevant predictors, a statistical model has been formulated, predictions were made
and the model can be validated (or revised) as additional data becomes available. The model used in the
web application has been formed taking into account neural network based minimum hamming distance
criterio
Divalent cation induced actin ring formation
No full textIn this paper we explored the effect of copper sulphate on the morphology of actin filaments. Actin filaments attain different shapes and structure when exposed to 2 mM concentration of copper sulphate. Lateral branches were observed after 4 h of incubation while shapes like Y- and V- were formed after 8 h of incubation. Rings and loops of actin filaments were formed when the concentration of copper sulphate was increased from 2 to 5 mM. Additionally, ring formation was also observed when bead tailed actin filaments were incubated with copper sulphate (5 mM). Electrostatic adhesion energy between ends of actin filaments attracted due to counterion was estimated to be 7.34 kT/μm. Divalent cation induced actin ring formation are similar to toroids of DNA but actin filaments have great bending stiffness due to large diameter of the ring formed. From these results we proposed that polyelectrolyte nature of actin filaments leads to the change in their morphology on exposure to high concentration divalent cations
Electro-chemical system for the determination of degree of unsaturation of edible oils
No full textThe research paper describes platinum–calomel electrodes electro-chemical system for the determination of degree of unsaturation of edible oils. The change in potential, when platinum and calomel electrodes are immersed in 2% iodine mono-chloride solution (ICl) in acetic acid with respect to iodine mono-chloride solution containing edible oil, has direct correlation to degree of unsaturation of edible oils. Edible oils have a chain of carbon atoms with double bonds where addition of halogen reagent takes place. In this investigation iodine mono-chloride solution in glacial acetic acid reacts with edible oils and change in potential of reaction mixture with respect to ICl stock solution using platinum and calomel electrodes relates to the degree of unsaturation of edible oils. A portable system has also been fabricated in which potential change directly relates to iodine number of the edible oils, which is directly displaced on Liquid Crystal Display (LCD)
Fiber Bragg grating interrogator using edge filtering technique with microbend loss error mitigation
No full textThis paper presents an edge filtering technique based interrogator for fiber Bragg grating sensors with microbend attenuation compensation system. The interrogator uses reference fiber along with the fiber in which the grating is inscribed to mitigate the effect of microbend attenuation in determining the Bragg wavelength of the sensor
Internally generated dynamic symbology in avionic display system
No full textSymbology is internally generated in Avionic Display System (ADS) which helps the pilot in situations of distress and also for testing purposes. Here we have discussed an internally generated dynamic symbology for meeting the requirements of ADS. Situations may arise during flight when the Mission Computer (MC) fails to deliver information to the ADS and the pilot faces a blank screen in front. In order to overcome this drastic situation, static optical information helps the pilot to navigate and for landing. In view of the current and future requirements, a Digital Signal Processor (DSP) based circuit has been designed and proposed which provide dynamic symbology instead of static optical symbolog
Analysis of data using neuro fuzzy approach recorded by instrumentation network installed at Mansa Devi (Haridwar) landslide site
Get PDFThis paper presents a case study of landslide monitoring and early warning of Mansa Devi (Haridwar), located at Haridwar by pass road. Data recorded by instrumentation network installed at Mansa Devi (Haridwar) landslide site by five sensors (Rain Guage, Inclinimeter, Tiltmeter, Crack meter, Earth pressure cell) was analyzed and a relationship between rainfall intensity-surface parameters and landslide occurrence drawn with neuro-fuzzy approach for prediction of landslide and concept of early warning system is also described. Mansa Devi site is found rain prone and developed model demonstrates a fairly accurate prediction
Effect of Airy disk on schlieren diffraction interferometer
No full textSchlieren is among the oldest and widely used optical techniques for detection of change in refractive index in transparent media. Present work demonstrates the effect of the position of schlieren element in the Airy pattern on the schlieren interferogram. It has been shown that the amplitude of the diffracted wave, starting from schlieren element and serving as an inbuilt reference beam for the schlieren diffraction interferometer, becomes maximum when schlieren element diffracts light from the Airy disk. Effect of F-number of the optical system on schlieren pattern is also demonstrated via observations on the amplitude of diffracted light
Development and optimisation of an HPLC method for the routine analysis of catechins, caffeine and gallic acid in tea (Camellia Sinesis)
No full textAn efficient and rapid high performance liquid chromatographic (HPLC) assay was developed for the quantification of catechins [(+) – catechin, (−) – epigallocatechin, (−) – epigallocatechingallate, (−) – epicatechin, and (−) – epicatechingallate], caffeine, and gallic acid in tea (Camellia Sinesis var. sinesis). The assay was optimized by varying sample strength, column temperature, gradient type, and detection wavelength. A curved gradient using a Thermo Hypersil ODS column with 0.05% orthophosphoric acid and methanol as mobile phase A and B, respectively, and UV detection at 277.5 nm was employed. It was observed that a curved gradient along with an optimal temperature, dramatically improves the signal to noise ratio and separation profile. The limit of detection (LOD) and limit of quantification (LOQ) were found to be in the range of 1.04–22.81 µg mL−1 and 3.47–76.05 µg mL−1 respectively. The overall precision values obtained from the analysis of Kangra and Darjeeling orthodox tea samples were within the range of 0–0.34 (standard error)
Voltammetric determination of citric acid and quinine hydrochloride using polypyrrole–pentacyanonitrosylferrate/platinum electrode
No full textCyclic voltammetry was used to investigate the electrochemical behavior of citric acid (CA) and quinine hydrochloride (QH) at a polypyrrole-pentacyanoferrate/Platinum (PPY–PCNFe/Pt) electrode in aqueous medium. The analytical plots obtained were found to be linear in the concentration range between 1.0 and 9.0 mM for both the analyte solutions. The detection limits (3δ) were found to be 1.17 × 10−4 M and 1.08 × 10−5 M for CA and QH analyte solutions, respectively. It was further observed that the diffusion of ionic species into and out of the polymeric film made the PPY–PCNFe/Pt electrode highly electroactive thereby enabling it to efficiently detect the analyte solutions having concentration as low as 1 mM