1,359 research outputs found
Geology and geochemistry of the Middle Proterozoic Eastern Ghat mobile belt and its comparison with the lower crust of the Southern Peninsular shield
Two prominent rock suites constitute the lithology of the Eastern Ghat mobile belt: (1) the khondalite suite - the metapelites, and (2) the charnockite suite. Later intrusives include ultramafic sequences, anorthosites and granitic gneisses. The chief structural element in the rocks of the Eastern Ghats is a planar fabric (gneissosity), defined by the alignment of platy minerals like flattened quartz, garnet, sillimanite, graphite, etc. The parallelism between the foliation and the lithological layering is related to isoclinal folding. The major structural trend (axial plane foliation trend) observed in the belt is NE-SW. Five major tectonic events have been delineated in the belt. A boundary fault along the western margin of the Eastern Ghats, bordering the low grade terrain has been substantiated by recent gravity and the deep seismic sounding studies. Field evidence shows that the pyroxene granulites (basic granulites) post-date the khondalite suite, but are older than the charnockites as well as the granitic gneisses. Polyphase metamorphism, probably correlatable with different periods of deformation is recorded. The field relations in the Eastern Ghats point to the intense deformation of the terrain, apparently both before, during and after metamorphism
Shape memory alloy based smart landing gear for an airship
The design and development of a shape memory alloy based smart landing gear for aerospace vehicles is based on a13; novel design approach. The smart landing gear comprises a landing beam, an arch, and a superelastic nickeltitanium shape memory alloy element. This design is of a generic nature and is applicable to a certain class of light13; aerospace vehicles. In this paper a specixFB01;c case of the shape memory alloy based smart landing gear design and13; development applicable to a radio controlled semirigid airship (radio controlled blimp) of 320 m3 volume is13; presented.Ajudicious combination of carbon xFB01;ber reinforced plastic for the landing beam, cane (naturally occurring13; plant product) wrapped with carbon xFB01;ber reinforced plastic for the arch, and superelastic shape memory alloy is13; used in the development. An appropriate sizing of the arch and landing beam is arrived at to meet the dual requirement of low weight and high-energy dissipation while ndergoing x201C;large elasticx201D; (large nonlinear recoverable13; elastic strain) deformations to ensure soft landings when the airship impacts the ground. The soft landing is required13; to ensure that shock and vibration are minimized (to protect the sensitive payload). The inherently large energydissipating character of the superelastic shape memory alloy element in the tensile mode of deformation and the superior elastic bounce back features of the landing gear provide the ideal solution.Anonlinear analysis based on the classical and xFB01;nite element method approach is followed to analyze the structure. Necessary experiments and tests have been conducted to check the veracity of the design. Good correlation has been found between the analyses and testing. This exercise is intended to provide an alternate method of developing an efxFB01;cient landing gear with satisfactory geometry for a x201C;certain class of light aerospace vehiclesx201D; such as airships, rotorcraft, and other light unmanned air vehicles
Development of a co-cured composite torque shaft for rudder of high speed aircraft
The Carbon Fibre reinforced Composites are widely used in developing various composite parts of civil and13; military aircraft due to its high specific strength and specific stiffness. Rudder being a primary control surface in an aircraft, it is subjected to various loads and needs high degree of structural integrity. Usually rudders are made of metal with many fasteners. In NAL we have designed and developed a composite rudder. Specialty of this13; rudder is that it has a torque shaft made up of carbon composite and has only few rivets. Conventionally torque13; shaft s are made up of special metals like titanium. The objective of this paper is to highlight the development of13; various tooling techniques used to fabricate the composite torque shaft . All major parts of the torque shaft are13; made by Co-curing technique and the metal attachments are embedded to the composite parts by self locking13; mechanism design. To qualify the torque shaft fatigue tests are done and ageing studies performed to prove13; structural integrity of the torque shaft under extreme environmental conditions. This paper portrays the13; development efforts, tolling and fabrication approaches for successful realization of the CFRP Torque Shaft
Finite Element Magnetostatic Analysis of Magnetostrictive (Tb0.3Dy0.7Fe1.95) Actuator with Different Housing Materials
Permeability of a housing material is one of the significant factors affecting the performance of Tb0.3Dy0.7Fe1.95 based magnetostrictive actuator. According to Lenz’s law the rate of flux transfer depends on permeability of housing material surrounding the terfenol-D. In this paper the co-axial coils in a free air are analysed under direct current excitation and the results are found to agree well with both analytical and Maxwell simulation. Also, the comparison of flux density distribution in co-axial coils placed inside different housing materials of magnetostrictive actuator is found by solving magnetostatic equations using Ansoft Maxwell 2D solver. The axial distribution of magnetic flux density, radial distribution of magnetic flux density and flux distribution in the actuator assembly with different housing materials namely mild steel, cast iron and aluminium with and without Terfenol-D are discussed.Defence Science Journal, 2013, 63(4), pp.423-428, DOI:http://dx.doi.org/10.14429/dsj.63.486
Development of CGLARE: Design, Fabrication and Characterisation
Fibre Metal Laminates (FMLs) are hybrid materials consisting of metal layers bonded to fibre-reinforced polymer layers. CGLARE is an FML developed at NAL consisting of thin aluminum foil combined with carbon-epoxy and glass-epoxy prepreg materials. CGLARE is proposed as the candidate material for the leading edges of wing and empennage of an aircraft as it has superior characteristics in terms of shape retention (due to highly linearly elastic material like carbon/epoxy), energy absorption capability (due to layered structure and plastic deformation), lightning protection (due to the presence of aluminum layers), and also due to its cost effectiveness (lightweight construction and simple production techniques). This paper describes the issues regarding the development of CGLARE such as surface preparation of aluminum foils and bonding of aluminum with glass. Tensile, Compression, ILSS and Flexure testing of ASTM standard CGLARE specimens for different layups have been done. An important design issue is the internal residual stresses built into the laminate during curing due to differential coefficients of thermal expansion of the different material systems. The paper presents these results that indicate some properties of these material systems that could be exploited for energy absorption in the leading edges of the aircraft
A STUDY OF METHOD DEVELOPMENT, VALIDATION AND FORCED DEGRADATION FOR SIMULTANEOUS QUANTIFICATION OF CABOZANTINIB AND NIVOLUMAB IN BULK AND PHARMACEUTICAL DOSAGE FORM BY RP-HPLC
Objective: The present paper describes a simple, accurate, and precise reversed-phase high-performance liquid chromatography (HPLC) method for rapid and simultaneous quantification of cabozantinib (CZT) and nivolumab (NVM) in bulk and pharmaceutical dosage form.
Methods: The chromatographic separation was achieved on Luna C18 (150 mm×4.6 mm, 3.5 μm). Mobile phase contained a mixture of 0.1% orthophosphoric acid and acetonitrile in the ratio of 50:50 v/v, flow rate 1.0 ml/min, and ultraviolet detection at 222 nm.
Results: The proposed method shows a good linearity in the concentration range of 20–300 μg/ml for CZT and 5–75 μg/ml for NVM under optimized conditions. Precision and recovery study results are in between 98 and 102%. In the entire robustness conditions, percentage relative standard deviation is <2.0%. Degradation has minimum effect in stress condition and solutions are stable up to 24 h.
Conclusion: This method is validated for different parameters such as precision, linearity, accuracy, limit of detection (LOD), limit of quantification (LOQ), ruggedness, robustness, and forced degradation study were determined according to the International Conference of Harmonization (ICH) Q2B guidelines. All the parameters of validation were found to be within the acceptance range of ICH guidelines. Since there is no HPLC method reported in the literature for the estimation of CZT and NVM in pharmaceutical dosage forms, there is a need to develop quantitative methods under different conditions to achieve improvement in sensitivity, selectivity, etc.
The author declares the interest to develop a validation and forced degradation for simultaneous quantification of CZT and NVM
Antecedents and Evolution of the Green Supply Chain
Supply chains have been developing over time since the inception of commercial trade and barter. The purpose of this paper is to describe the emergence of the Green Supply Chain, the newest entry in supply chain evolution. As a foundation for this, historical perspectives of manufacturing chronology, along with supply chain modifications resulting from changing market conditions are discussed. Managerial implications are offered reflecting pathways towards sustainability.As production power shifted from manual operation to steam, technology became the main driver for supply chain development leading to a variety of types seen in industry today. Today\u27s supply chain types emerged due to increasing market complexity and competitive pressure. More recently, an additional driver occurred catalyzing the Green Supply Chain - the Environmental Movement. This chain is positioned as the next step in today\u27s supply chain evolution, balancing environmental, economic, and societal needs with customer growth
Design, Development and Optimization of Controlled Release Tablet of Fluconazole.
The purpose of this research was to prepare controlled release tablets of Fluconazole in reducing the dose and increasing efficiency with reducing fluctuations.By controlling the rate
of release the side effects such as hallucinations and paranoid behaviour will also be minimized.A 22 factorial design was employed to optimize the formulations,producing 4 factorial points,this design generally involves dependent variables Y,independent variable X.The independent variable selected for this study were (X1-X4),X1amount of maltodextrin,X2 amount of Carbopol 940, X3 amount of HPMC,X4 amount of Ethyl cellulose.The dependent variable were (Y1-Y4),Y1 hardness,Y2 amount of drug release at 1st hour, Y3 time taken to reach t50%, Y4 Zone of inhibition.Controlled release release tablets have been prepared incorporating antifungal drug Fluconazole using polymers like Maltodextrin,HPMC,Carbopol 940,Ethyl Cellulose.The anti microbial studies showed good antifungal activity based on zone of inhibition.The invitro drug release studies revealed that as the concentration of polymer increased the drug release decreased.Formulations containing
higher concentration of polymers were able to efficiently control Fluconazole release over a time period of 8hrs.The formulations containing 2:2 ratio of polymers gave the best results, among which the formulation containing Carbopol-940:HPMC with 2:2 ratio of polymers is concluded as best formulation in terms of required drug release in a controlled release manner. The drug release mechanism was confirmed as case-II transport or typical zero-order
release.IR spectra matching confirmed that there was no major interaction between the drug and the excipients used
Changes at transcriptional level in the rat liver following whole-body X-irradiation
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