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At present Dhruva and Cirus reactors provide the majority of research reactor based facilities to cater to the various needs of a vast pool of researchers in the field of material sciences, physics, chemistry, bio sciences, research & development work for nuclear power plants and production of radio isotopes. With a view to further consolidate and expand the scope of research and development in nuclear and allied sciences, a new 20 MWt multi purpose research reactor is being designed. This paper describes some of the design features and safety aspects of this reactor.  相似文献   
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Classical and quantum world views differ in peculiar ways. Understanding decisive quantum features—for which no classical explanation exist—and their interrelations is of foundational interest. Moreover, recognizing non-classical features carries practical significance in information processing tasks as it offers insights as to why quantum protocols work better than their classical counterparts. We focus here on two celebrated notions of non-classicality viz., negativity of P phase–space representation and entanglement in symmetric multiqubit systems. We prove that they imply each other.  相似文献   
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The node-link diagram is an intuitive and venerable way to depict a graph. To reduce clutter and improve the readability of node-link views, Holten & van Wijk's force-directed edge bundling employs a physical simulation to spatially group graph edges. While both useful and aesthetic, this technique has shortcomings: it bundles spatially proximal edges regardless of direction, weight, or graph connectivity. As a result, high-level directional edge patterns are obscured. We present divided edge bundling to tackle these shortcomings. By modifying the forces in the physical simulation, directional lanes appear as an emergent property of edge direction. By considering graph topology, we only bundle edges related by graph structure. Finally, we aggregate edge weights in bundles to enable more accurate visualization of total bundle weights. We compare visualizations created using our technique to standard force-directed edge bundling, matrix diagrams, and clustered graphs; we find that divided edge bundling leads to visualizations that are easier to interpret and reveal both familiar and previously obscured patterns.  相似文献   
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Interactive history tools, ranging from basic undo and redo to branching timelines of user actions, facilitate iterative forms of interaction. In this paper, we investigate the design of history mechanisms for information visualization. We present a design space analysis of both architectural and interface issues, identifying design decisions and associated trade-offs. Based on this analysis, we contribute a design study of graphical history tools for Tableau, a database visualization system. These tools record and visualize interaction histories, support data analysis and communication of findings, and contribute novel mechanisms for presenting, managing, and exporting histories. Furthermore, we have analyzed aggregated collections of history sessions to evaluate Tableau usage. We describe additional tools for analyzing users’ history logs and how they have been applied to study usage patterns in Tableau.  相似文献   
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ABSTRACT: Our knowledge about the metabolism of alkylcyclobutanones (2-ACBs) is limited, and the lack of literature on the metabolism of 2-ACBs causes consumers to doubt the safety of irradiated foods. The objectives of this study were to evaluate the metabolism of 2-dodecylcyclobutanone (2-DCB) and identify any possible metabolite. The 2-DCB was mixed with rat S9 (postmitochondrial supernatant fraction) and β-nicotinamide adenine dinucleotide phosphate (NADPH) in phosphate buffer (pH 7.4) and incubated for 2 h at 37 °C. Then, the incubation mixture was mixed with sodium sulfate and extracted with n-hexane by using a Soxhlet apparatus. The hexane extract was concentrated under nitrogen and injected into the gas chromatography-mass spectrometry (GC-MS) machine running in selective ion monitoring mode (SIM) to measure 2-DCB concentration. The hexane extract from the in vitro and in vivo studies was also derivatized with a silylation reagent and injected into a GC-MS running in full scan mode. The average percentage of 2-DCB recovered from the test incubations was 23%, compared with 50% from the controls. The GC-MS chromatograms of the derivatized samples showed a unique peak in the in vitro test incubations and in the hexane extract of the rat feces that were given 2-DCB. This peak was later identified as 2-doecylcyclobutanol.  相似文献   
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The algebraic identity(ab)^{-1} = (b pm a)^{-1}(a^{-1} pm b^{-1})is used to reduce the average over thermal velocities of a product of Lorentzian line shapes to a product of Lorentzian line shapes which do not depend on velocity and a sum of plasma dispersion Z-functions. Scaling is used to cancel the velocity-dependent terms in(b pm a).(abc... )^{-1}may be reduced by systematic application of the above identity and tedious integrations can be replaced by algebraic procedures.  相似文献   
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