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The Indian Institutes of technology (IITs) in India account for significant research outcomes from the country. This paper is an attempt to analyze the publications of five older IITs during the period 2007 to 2016 as reflected in...
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The Indian Institutes of technology (IITs) in India account for significant research outcomes from the country. This paper is an attempt to analyze the publications of five older IITs during the period 2007 to 2016 as reflected in SCOPUS, multi-disciplinary international database. A total of 10583 research publications have been downloaded and analyzed. This paper tries to give an overview of the research output of the five IITs (IIT Bombay, IIT Kanpur, IIT Kharagpur, IIT Delhi, and IIT Madras) on different parameters like growth rate of research publications, authorship pattern, productivity per capita, degree of collaboration, etc.
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Pc4 signatures for the year 2013, extracted from geomagnetic north south and east-west components of induction coil magnetometer (LEMI 30) from low latitude station Desalpar (DSP), operated by Institute of Seismological Research (...
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Pc4 signatures for the year 2013, extracted from geomagnetic north south and east-west components of induction coil magnetometer (LEMI 30) from low latitude station Desalpar (DSP), operated by Institute of Seismological Research (ISR), India have been investi-gated vis-a-vis the prevalent interplanetary parameters (IMF) as well as the geomagnetic activity indices. A clear dominance of Pc4-5 (467 events) over Pc3 (17 events) is observed. Local time variation of Pc4 shows a peak in the noon sector in both X and Y components. Our investigations show that the dominant peak frequency is 10 mHz at low latitude region. Correlations with solar wind and IMF parameters illustrate highest occurrence of Pc4 for a solar wind speed of 300-400 km/s and average IMF B field of 3-6 nT. The amplitude of Pc4s at DSP shows an increase with increasing solar wind speed, plasma density, solar wind dynamic pressure and average B field which is also reflected in the trend of frequency variation of these pulsations. We report that IMF clock angle at low latitude does not have influence on Pc4 occurrence. Based on the characteristics of these events, detected in latitudinally distributed stations from low and mid-latitudes from northern and southern hemisphere, we infer that modes were compressional, which could be driven by K-H instability or solar wind dynamic pressure, as compressional modes can propagate to low latitude with little attenuation.
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The focus of this study is identification, isolation and characterization of a principal oxidation impurity of clopidogrel which ranged from 0.05 to 0.12% using high performance liquid chromatography. This impurity is considered a...
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The focus of this study is identification, isolation and characterization of a principal oxidation impurity of clopidogrel which ranged from 0.05 to 0.12% using high performance liquid chromatography. This impurity is considered as principal oxidation impurity as it is observed in oxidative degradation (stress) study. Preparative HPLC with Xterra MS C18 ODB column was used to isolate the impurity. The isolated impurity was co-injected with the sample containing impurities and found the retention time match of the spiked impurities. A thorough study was undertaken to characterize this impurity and based on their spectral data (UV, MS, MSn 1H/13C, DEPT and 2D NMR) the structure was characterized as 5-[1-(2-chlorophenyl)-2-methoxy-2-oxoethyl]-6,7-dihydrothieno[3,2-c]pyridin-5-ium with a molecular weight 320 amu.
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Fusarium Wilt caused by Fusarium oxysporum f. sp. lycopersici is a major constraint of tomato production all over the world. Progress in selection for fungal-resistant lines can be speeded up by the use of molecular markers associ...
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Fusarium Wilt caused by Fusarium oxysporum f. sp. lycopersici is a major constraint of tomato production all over the world. Progress in selection for fungal-resistant lines can be speeded up by the use of molecular markers associated with genes of resistance. Eight microsatellite regions were used to amplify the DNA of tomato lines (3 resistant 2 susceptible and 3 tolerant). Among loci initially analyzed, SSR-67 was highly polymorphic in the resistant, tolerant and susceptible population. The markerselected is inherited and segregated in Mendelian fashion as demonstrated on a panel of 25F_2 and 20F_1 offspring derived from a cross of two divergent cultivars GP-10 (wilt resistant) and GT-2 (wilt tolerant).
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Laccase is an oxidoreductase (EC 1.10.3.2.) that catalyzes the oxidation of phenolic substrates by molecular oxygen and is found in a variety of lignin degrading fungal strains (Thurston 1994). Laccase has wide applications in bio...
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Laccase is an oxidoreductase (EC 1.10.3.2.) that catalyzes the oxidation of phenolic substrates by molecular oxygen and is found in a variety of lignin degrading fungal strains (Thurston 1994). Laccase has wide applications in biotechnology: dye decolourization, degradation of xenobiotics, biopulping, biobleaching, etc., (Couto and Herrera (2006) and Mayer and Staples (2002). Several methods (submerged and solid state fermentation) are available for laccase production. The effect of temperature, pH,carbon source and nitrogen sources were also studied in detail for laccase production (Baldrian 2006).
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Experimental investigations on the role of ion mass and the primary knock-on atoms (PKA) spectrum in the defect type, structure and defect production efficiency is presented in ion-irradiation experiments in tungsten using a combi...
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Experimental investigations on the role of ion mass and the primary knock-on atoms (PKA) spectrum in the defect type, structure and defect production efficiency is presented in ion-irradiation experiments in tungsten using a combination of positron annihilation spectroscopy, transmission electron microscopy and secondary ion mass spectroscopy. Recrystallized tungsten foils were irradiated using low- (helium), medium- (boron) and high-mass (gold) ions of MeV energy for a comparable dpa and implantation range at room temperature. Depending on the ion mass and the PKA spectrum, distinctly different defect structures were observed at the atomistic as well as meso-scales. While no indication of dislocation lines was observed in 3 MeV helium irradiated samples, the boron and gold ions showed extensive dislocation line formation. The cluster shape depends on the PKA energy and the cluster density depends on the irradiation fluence. The depth profile analysis of the defects in the helium-irradiated samples showed extensive helium trapping throughout the implantation range. Significant sub-surface helium trapping is observed within 700 nm from the surface, indicating that they moved towards the surface from their mean implantation depth of 4500 nm. The study also shows a correlation between carbon and helium profiles in the samples.
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Electrical impedance tomography is a recently established technique by which impedance of an object (medical or nonmedical applications) is measured data from the surface of the object, and a numerically simulated reconstruction o...
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Electrical impedance tomography is a recently established technique by which impedance of an object (medical or nonmedical applications) is measured data from the surface of the object, and a numerically simulated reconstruction of the object internal shape of the image can be obtained. This imaging technique based on boundary or surface voltage is measured when the different current pattern is injected into it. For current pulse, we are creating a voltage controlled current source, which is based on the different RC circuits, according to current amplitude and frequency values. The current source used in inject the current pulse of the various phantoms. The current position and measuring voltage is controlled by the created control unit or programmable system on chip (PSOC) of the proposed EIT system. After that image reconstruction of the cross-sectional image of resistivity requires sufficient data collection from used phantoms, which is based on finite element method (FEM) method and Tikhonov regularization method with helps of graphical user interface (GUI) on MatLab. The objective of the GUI was to produce an image (2D/3D), impedance distribution graph, and the FEM mesh model according to used electrode combinations from the various phantoms. EIT system has a great potential for imaging modality, is non-invasive, radiation-free, and inexpensive for medical applications.
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A unique combination of pulsed dc and radio frequency (RF) discharge deposition was used to deposit thick (～5 μm) and adherent (2-4 MPa) Teflon-like coatings on a stainless steel (SS) shell of 2 m diameter size, through plasma e...
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A unique combination of pulsed dc and radio frequency (RF) discharge deposition was used to deposit thick (～5 μm) and adherent (2-4 MPa) Teflon-like coatings on a stainless steel (SS) shell of 2 m diameter size, through plasma enhanced chemical vapor deposition (PECVD). The details of deposition on such a big industrial scale component are reported for the first time. In this method, highly adherent thin interface layers were grown on SS shell that was electrically grounded, using pulsed dc discharge, followed by RF discharge deposition to build up the required coating thickness. The fluorocarbon precursor molecules, required for the deposition of Teflon-like coating, are generated indigenously by pyrolyzing the Teflon powder. The deposited coating was studied for its chemical bond state, surface roughness (Ra), morphology, thickness, and adhesive strength. These studies were carried out by using XPS, AFM, SEM, etc. The adhesive strength of the coating was measured by pin-pull test as per ASTM D4541 standard test. The coatings deposited with pulsed dc discharge were observed to have higher adhesive strength when compared with those deposited with RF discharge.
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In this work, Plasma Nitriding was carried out at a temperature of 570°C on nuclear grade austenitic stainless steel type AISI 316 LN (316LN SS) in a gas mixture of 20% N _2-80% H _2 to improve the surface hardness and thereby sl...
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In this work, Plasma Nitriding was carried out at a temperature of 570°C on nuclear grade austenitic stainless steel type AISI 316 LN (316LN SS) in a gas mixture of 20% N _2-80% H _2 to improve the surface hardness and thereby sliding wear resistance. The Plasma Nitride (PN) treated surface has been characterized by Vickers microhardness measurements, Scanning Electron Microscopic (SEM) examination, X-ray Diffraction (XRD) and sliding wear assessment. The average thickness of the PN layer was found to be 70μm. Microhardness measurements showed a significant increase in the hardness from 210 HV ~(25)g (unnitrided sample) to 1040 HV _(25)g (Plasma Nitrided sample). The XRD reveals that PN layer consists of CrN, Fe _4N and Fe _3N phases along with austenite phase. The tribological parameters such as the friction coefficient and wear mechanism have been evaluated at ambient conditions for PN treated ring (PN ring) vs. ASTM A453 grade 660 pin (ASTM pin), PN ring vs. Nickel based alloy hard faced pin (Colmonoy pin), PN ring vs. 316LN SS pin and 316LN SS ring vs. 316LN SS pin. The wear tracks have been analyzed by SEM, Energy Dispersive X-ray Analysis (EDX) and Optical Profilometry. The untreated 316LN SS ring vs. 316LN SS pin produced severe wear and was characterized by a combination of delamination and adhesion wear mechanism, whereas wear mechanism of the PN rings reveals mild abrasion and a transfer layer from pin materials.
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The nucleus ~(141)Nd has been investigated using two different heavy ion fusion evaporation reactions, namely ~(130)Te(~(16)O, 5n) at E_(lab) = 80-85 MeV and ~(124)Sn(~(24)Mg, α3n) at E_(lab) = 107 MeV, and the de-exciting gamma ...
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The nucleus ~(141)Nd has been investigated using two different heavy ion fusion evaporation reactions, namely ~(130)Te(~(16)O, 5n) at E_(lab) = 80-85 MeV and ~(124)Sn(~(24)Mg, α3n) at E_(lab) = 107 MeV, and the de-exciting gamma rays were detected using HPGe(GDA) and Clover detector (INGA) arrays, respectively. More than 30 new gamma transitions have been placed in the proposed level scheme, which has been extended up to 9 MeV excitation energy and spin parity values of 45/2-. Spin parity assignments have been made to most of the newly proposed levels. The structure up to approximately 6 MeV excitation energy and spin 31/2~- can be explained using the shell model in a truncated basis. The levels with higher spin/energy cannot be described using even the full 50-82 shell, indicating the influence of neutron excitations across the shell gap in this mass region. One M1 band that has been observed is proposed to have a five quasiparticle configuration.
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