1,465 research outputs found
A star-forming galaxy at z= 5.78 in the Chandra Deep Field South
Get PDFWe report the discovery of a luminous z = 5.78 star-forming galaxy in the Chandra Deep Field South. This galaxy was selected as an ‘i-drop’ from the GOODS public survey imaging with the Hubble Space Telescope/Advanced Camera for Surveys (object 3 in the work of Stanway, Bunker & McMahon 2003). The large colour of (i′−z′)AB = 1.6 indicated a spectral break consistent with the Lyman α forest absorption shortward of Lyman α at z≈ 6. The galaxy is very compact (marginally resolved with ACS with a half-light radius of 0.08 arcsec, so rhl 5. Our spectroscopic redshift for this object confirms the validity of the i′-drop technique of Stanway et al. to select star-forming galaxies atz≈ 6
The use of conservative integral in bi-material interface crack problems subjected to thermal loads
No full textAbstractA linear bi-material elastic body containing a crack at the interface and subjected to thermal loading is analyzed. The J2 line integral, developed for mechanical loads by Khandelwal and Chandra Kishen [Khandelwal, Chandra Kishen, J.M., 2006. Complex variable method of computing Jk for bi-material interface cracks. Engineering Fracture Mechanics 73, 1568–1580] is extended to thermal loading. This method, used in conjunction with the finite element method, is shown to be useful in the prediction of stress intensity factors for cracks lying at the interface of two dissimilar materials and subjected to any type of thermal loading
Chandra, Subrato - Professor of Aerospace Engineering
No full textDr. Subrato Chandra, Professor of Aerospace Engineering, holding an apparatus. He has focused his career on solar power, and is the author of A Guide to Solar Water Heating in Florida.https://stars.library.ucf.edu/univphotocollection/1588/thumbnail.jp
Negatively supercharging cellulases render them lignin-resistant
No full textNon-specific adsorption of cellulases to lignin hinders enzymatic deconstruction of lignocellulosic biomass. Here we tested the hypothesis that negatively supercharging cellulases could reduce lignin inhibition. Computational design was used to negatively supercharge the surfaces of Ruminoclostridium thermocellum family 5 CelE and a CelE-family 3a carbohydrate binding module fusion. Resulting designs maintained the same expression yield, thermal stability, and nearly identical activity on soluble substrate as the wild-type proteins. Four designs showed complete lack of inhibition by lignin but with lower cellulose conversion compared to original enzymes. Increasing salt concentrations could partially rescue the activity of supercharged enzymes, supporting a mechanism of electrostatic repulsion between designs and cellulose. Results showcase a protein engineering strategy to construct highly active cellulases that are resistant to lignin-mediated inactivation, although further work is needed to understand the relationship between negative protein surface potential and activity on insoluble polysaccharides.Peer reviewe
Radio sources in the Chandra Galactic Bulge Survey
Get PDFWe discuss radio sources in the Chandra Galactic Bulge Survey region. By cross-matching the X-ray sources in this field with the NRAO VLA Sky Survey archival data, we find 12 candidate matches. We present a classification scheme for radio/X-ray matches in surveys taken in or near the Galactic plane, taking into account other multiwavelength data. We show that none of the matches found here is likely to be due to coronal activity from normal stars because the radio to X-ray flux ratios are systematically too high. We show that one of the source could be a radio pulsar, and that one could be a planetary nebula, but that the bulk of the sources are likely to be background active galactic nuclei (AGN), with many confirmed through a variety of approaches. Several of the AGN are bright enough in the near-infrared (and presumably in the optical) to use as probes of the interstellar medium in the inner Galaxy
Religion, Culture and Nationalism in India. <br>: Interview with Sudhir Chandra (Mizoram University, India).
No full textFonds audiovisuel du programme "ESCoM-AAR" (Equipe Sémiotique Cognitive et nouveaux Médias - Archives Audiovisuelles de la Recherche. Paris, France, 2000 - 2016).Sudhir CHANDRA is an historian. His main research topic is the formation of national indian consciousness in the XXe century.He has published in 2002 Continuing Dilemmas: Understanding Social Consciousness (New Delhi, Tulika Books). He is also the author of Enslaved Daughters: Colonialism, Law and Women's Right (New Delhi, Oxford University Press, 1997), The Oppressive Present: Literature and Social Consciousness in Colonial India (New Delhi, Oxford University Press, 1992) and Dependence and Disillusionment: Emergence of National Consciousness in Later Nineteenth Century India (New Delhi, Manas, 1975)
Religion, Culture and Nationalism in India. <br>: Interview with Sudhir Chandra (Mizoram University, India).
No full textFonds audiovisuel du programme "ESCoM-AAR" (Equipe Sémiotique Cognitive et nouveaux Médias - Archives Audiovisuelles de la Recherche. Paris, France, 2000 - 2016).Sudhir CHANDRA is an historian. His main research topic is the formation of national indian consciousness in the XXe century.He has published in 2002 Continuing Dilemmas: Understanding Social Consciousness (New Delhi, Tulika Books). He is also the author of Enslaved Daughters: Colonialism, Law and Women's Right (New Delhi, Oxford University Press, 1997), The Oppressive Present: Literature and Social Consciousness in Colonial India (New Delhi, Oxford University Press, 1992) and Dependence and Disillusionment: Emergence of National Consciousness in Later Nineteenth Century India (New Delhi, Manas, 1975)
Studies On The Evaluation Of Thermal Stress Intensity Factors For Bi-Material Interface Cracks
No full textComponents of turbines, combustion chambers, multi-layered electronic packaging structures and nuclear reactors are subjected to transient thermal loads during their service life. In the presence of a discontinuity like crack or dislocation, the thermal load creates high temperature gradient, which in turn causes the stress intensification at the crack tips. If proper attention is not paid in the design and maintenance of components on this high stress in the vicinity of crack tips, it may lead to instability in the system and decrease in the service life. The concepts of thermal fracture mechanics and its major parameter called transient thermal stress intensity factors can greatly help in the assessment of stability and residual life prediction of such structures.
The evaluation of thermal stress intensity factors becomes computationally difficult when the body constitutes of two different materials or is non-homogenous or made of composites. Fracture at bi-material interface is different from its homogenous counterpart because of mixed mode stress condition that prevails at the crack tip even when the geometry is symmetric and loading unidirectional. Because of this, the mode 1 and mode 2 stress intensity factors can not be decoupled to represent tension and shear stress fields as can be done in the case of homogeneous materials. Mathematically, the stress intensity factors at bi-material interfaces are complex due to oscillatory singularity that exists at the crack tip.
Although plenty of literature is available for bi-material systems subjected to mechanical loads, very little information is available on problems related to thermal loads. Besides, problems related to transient thermal loads need special attention, since no thermal weight functions are available and the existing methods are computationally expensive. Therefore, the present investigation has been undertaken to develop computational and analytical approaches for obtaining the Mode 1 and Mode 2 stress intensity factors for bi-material interface crack problems using conservation of energy principle in conjunction with the weight function approach for various kinds of thermal loads. In the beginning of the studies, a method to extract the Mode 1 and Mode 2 stress intensity factors for bi-material interface crack subjected to mechanical load is proposed using the concept of Jk integrals. This is extended to thermal loads using J2 line integral and J2 domain integral. Furthermore, weight functions are analytically derived for thermal bi-material stress intensity factors and a computational scheme is developed. These methods are validated for several benchmark problems with known solutions
Inductive local-global conditions and generalised Harish-Chandra theory
No full textWe study new properties of generalised Harish-Chandra theory aiming at explaining the inductive local-global conditions for finite groups of Lie type in nondefining characteristic. In particular, we consider a parametrisation of generalised Harish-Chandra series that is compatible with Clifford theory and with the action of automorphisms on irreducible characters and we reduce it to the verification of certain requirements on stabilisers and extendibility of characters. This parametrisation is used by the author in a separate paper to obtain new conjectures for finite reductive groups that can be seen as geometric realisations of the local-global counting conjectures and their inductive conditions. As a by-product, we extend the parametrisation of generalised Harish-Chandra series given by Broué–Malle–Michel to the nonunipotent case by assuming maximal extendibility
Writing Chandra Levy: Real life, ritual, revision
No full textThis piece explores how national events affect art by chronicling one author\u27s writing process. Specifically, this piece looks at how September 11, 2001, affected the writing of a play about missing intern Chandra Levy. Though overshadowed by the nation-changing events, the scandal surrounding Levy\u27s disappearance was a top news story in the summer of 2001. This essay explores one author\u27s writing process as a play morphed in the face of national cataclysm. By tracing and describing revision, the piece explores how an academic exercise about the liminality of missing-ness turned into a religious ritual promoting compassion. © 2011 National Communication Association
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