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Diffraction Lloyd mirror interferometer
No full textPresent work describes the principle and realization of diffraction Lloyd’s mirror interferometer. In this new system light diffracted from an aperture is divided into two wavefronts which are again superimposed on each other with the help of a Lloyd’s mirror. This setup generates two beam interference fringes analogous to that the well known Lloyd’s mirror interferometer. It has been shown that these interference fringes can be produced with vertical as well as horizontal polarized incident light. Experimental test results on phase objects using this system are also presented. Further, applications of this interferometer are discussed in various emerging fields
Spatiotemporal parameters measurement of human gait using developed FSR for prosthetic knee joint
No full textMeasuring the heel strike and toe time during walking provides valuable insight to the spatiotemporal parameters of human gait. The authors developed a sensor mechanism using FSR. Result shows that FSR sensor show high degree of accuracy and repeatability for measuring heel strike and toe contact time. The objective of the research was to develop a rugged and robust sensor mechanism to be used in prosthetic shoes which will help to determine the gait parameters for precise control of intelligent prosthetic devices.
Neelesh Kumar, Davinder Pal Singh, Amod Kumar, B.S. Soh
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.
, , M. L. Singl
Low cost prototype development of electronic knee
Get PDFThis study presents design and development of an electronic knee, which uses attached sensors, microcontrollers andelectro pneumatic valve arrangement to emulate near natural walk. Being all sensors and mechanical assembly developedindigenously, prototype would be a low cost electronic knee
Self healing biologically inspired Nanoreinforced polymer composite For improved fatigue tolerance And reliability of bioimplants
No full textIn this study, a self-healing, multi walled carbon nanotubes (MWNT) nanoreinforced polymer composite is formed
which may be used as biomaterial to manufacture bioimplants like artificial blood vessels; or as coating material for metallic implants like pacemakers, artificial hip and knee to avoid corrosion and increase the life of the implant. The self-healing approach employs a releasable healing agent incorporated in a hollow fiber embedded in an epoxy resin system. The generation and filling of the crack is a simultaneous process. The crack propagates through the polymer composite and breaks the hollow fiber which results
in the leaking of the liquid healing agent, which fills the crack. The catalyst is pre-coated on the outer surface of the fiber to facilitate the polymerization of the monomer healing agent. Virgin, damaged and healed samples of the nanoreinforced polymer composite are tested proving that the addition of functionalized carbon nanotubes in the healing agent leads to better fracture toughness and tensile strength recovery
Catalytic studies of palladium nanoparticles immobilized on alumina synthesized by a simple physical precipitation method
No full textIn this study, a high catalytic activity of palladium nanoparticles immobilized on alumina (Al2O3) is reported for the industrially important reduction of aromatic nitro compounds to amino compounds. The palladium nanoparticles were immobilized on alumina by a simple physical precipitation method. The synthesis of palladium nanoparticles was done in ethylene glycol without using any external stabilizing agent. The composite particles exhibited good colloidal stability. The catalytic activity is investigated qualitatively by high performance liquid chromatography (HPLC) and quantitatively by photometrically monitoring the reduction of p-nitrophenol by an excess of sodium borohydride (NaBH4) in the presence of nanocomposites. The kinetic data could be explained by the assumption of pseudo first-order reaction with respect to p-nitropheno
Recovery of copper from zinc leaching liquor using ACORGA M5640
No full textThe present paper describes the solvent extraction and separation of Cu(II) from a leaching liquor obtained by the direct atmospheric leaching of a zinc concentrate with an oxidative mixture of Fe2(SO4)3 (0.4 M) and H2SO4 (0.5 M) in the presence of O2 at 353 K. The obtained solution, containing 1.35 g L−1 Cu(II), 5 mg L−1 In(III), 41 g L−1 Fe {20% Fe(III), 80% Fe(II)}, and 34 g L−1 Zn(II), was extracted with 25% (v/v) solution of ACORGA M5640 (modified with 12.5% (v/v) isodecanol). Quantitative (>98%) and selective transfer of Cu(II) in to the organic phase was achieved in pH range of 1.3–1.5 (A/O = 1). The presence of isodecanol in the extractant solution helped in obtaining complete stripping of copper. Three stages of extraction at an A/O ratio of 5 concentrated the initial metal content {Cu(II)initial-aqueous = 1.35 g L−1} in the organic phase {Cu(II)after extraction, in LO = 6.6 g L−1}. This extraction was selective over Zn(II), Fe(II), Fe(III), and In(III). The loaded organic phase was scrubbed with 20 g L−1 H2SO4 followed by the stripping of Cu(II) with 25 g L−1 of Cu2+ in 180 g L−1 of H2SO4 (A/O = 1, two stages)
PLC Based Automatic Control of Rheometer
Get PDFThis paper describes the automatic control of disc type rheometer. This developed device will able to provide flexibility to operator for testing of rubber. The operator has to just enter the duration of test and parameters through man machine interface. All the operations will occur
automatically without any intervention in a prescribed sequence stored in programmable logic controller (PLC). This developed apparatus is useful not only for testing purpose, but it can be used for research for other types of materials also. With this state of art apparatus one can control the quality of rubber for various applications such as tyre industry. Also this would help to increase the production of rubber as automatic control comes which reduces the test duration to few minutes only.
A.M Gaur1*, Rajesh Kumar 2, Amod Kumar3 and Dinesh Singh Rana
Modelling of Laser Scanning System to Determine its Associated Uncertainty of Measurement
No full textIn the fabrication of fine wires such as filaments of lamps and optical fibers, it is always necessary to measure the diameter in real-time and correct the extrusion process. For metrological purposes, laser beam scanning technique will produce similar results as comparative to diffraction-assisted methods. A computerized laser beam scanning measurement system (LSM) is designed and fabricated. The LSM
consists of a low power helium-neon gas laser source, a specially designed collimating lens, a hysteresis
synchronous motor, a photo detector and a protective replaceable window along with temperature sensor. The LSM is mathematically modeled to identify various error contributing sources. The LSM is calibrated using a set of national reference standard cylindrical pins and a set of national reference standard slots to determine its relative calibration factor. The uncertainty of measurement achieved in the range of (0-35) mm is ± (0.55 +39.2L/m) μm
Detection of jaggery syrup in honey using near-infrared spectroscopy
No full textIn the present study, a near-infrared (NIR) filter-based technique along with chemometrics as an analytical tool was used for determination of adulteration of Indian honey with jaggery. A total of 56 honey samples adulterated with different concentrations of jaggery syrup were analyzed using the NIR transflectance method at different wavelengths for multivariate analysis to develop a calibration model for jaggery adulteration in honey samples. The data were compressed using principal component analysis method and the model was developed using partial least square regression. The adulteration of all of the samples can be predicted with a standard error of calibration of 4.55 and a coefficient of determination (R(2)) of 0.81. The results demonstrate that the NIR technique along with chemometrics can be successfully used to determine jaggery adulteration in honey non-destructively.
Sunita Mishra, Uma Kamboj, Harpreet Kaur & Pawan Kapur
Read More: http://informahealthcare.com/doi/abs/10.3109/0963748090347641