13,341 research outputs found
A CONDENSER FOR THE VACUUM DISTILLATION OF METALS
A condenser. suitable for use in the distillation of metals was designed. The temperature of the condensing surface was established by controlling the pressure over boiling NaK-78 contained within the condenser. Performance was evaluated in test units in which pure bismuth was distilled as the test metal
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Investigating collaborative annotation on slate PCs
Mobile reading is becoming evermore popular with the introduction of eInk devices such as the Kindle, as well as the many reading applications available on slate PCs and cellular handsets. The portable nature and large storage capacity of these modern mobile devices is making reading a more technology orientated activity. One aspect of mobile reading that has been given surprisingly little attention is collective reading - which is a common activity with paper documents. We investigate the support of group reading using slate PCs, focussing on collective annotation. In the past, desktop PCs have proved inferior in many ways for reading, when compared to paper. Notably, user evaluations of our new system, BuddyBooks, demonstrate that the slate PC form factor can, in contrast, provide advantages for group reading. While annotation practices change with the new format, coordinating within the group can be improved when touch-interaction is carefully exploited
Co-reading: investigating collaborative group reading.
Collaborative reading, or co-reading as we call it, is ubiquitous—it occurs, for instance, in classrooms, book-clubs, and in less coordinated ways through mass media. While individual digital reading has been the subject of much investigation, research into co-reading is scarce. We report a two-phase field study of group reading to identify an initial set of user requirements. A co-reading interface is then designed that facilitates the coordination of group reading by providing temporary ‘Point-out’ markers to indicate specific locations within documents. A user study compared this new system with collaborative reading on paper, with a positive outcome; the differences in user behavior between paper and the new interface reveal intriguing insights into user needs and the potential benefits of digital media for co-reading
A clinical analysis of the keystone astigmatism dial card
A clinical analysis of the keystone astigmatism dial car
The Electronic and Superconducting Properties of Oxygen-Ordered MgB2 compounds of the form Mg2B3Ox
Possible candidates for the Mg2B3Ox nanostructures observed in bulk of
polycrystalline MgB2 (Ref.1) have been studied using a combination of
Z-contrast imaging, electron energy loss spectroscopy (EELS) and
first-principles calculations. The electronic structures, phonon modes, and
electron phonon coupling parameters are calculated for two oxygen-ordered MgB2
compounds of composition Mg2B3O and Mg2B3O2, and compared with those of MgB2.
We find that the density of states for both Mg2B3Ox structures show very good
agreement with EELS, indicating that they are excellent candidates to explain
the observed coherent oxygen precipitates. Incorporation of oxygen reduces the
transition temperature and gives calculated TC values of 18.3 K and 1.6 K for
Mg2B3O and Mg2B3O2, respectively.Comment: Submitted to PR
WFPC2 LRF Imaging of Emission Line Nebulae in 3CR Radio Galaxies
We present HST/WFPC2 Linear Ramp Filter images of high surface brightness
emission lines (either [OII], [OIII], or H-alpha+[NII]) in 80 3CR radio
sources. We overlay the emission line images on high resolution VLA radio
images (eight of which are new reductions of archival data) in order to examine
the spatial relationship between the optical and radio emission. We confirm
that the radio and optical emission line structures are consistent with weak
alignment at low redshift (z < 0.6) except in the Compact Steep Spectrum (CSS)
radio galaxies where both the radio source and the emission line nebulae are on
galactic scales and strong alignment is seen at all redshifts. There are weak
trends for the aligned emission line nebulae to be more luminous, and for the
emission line nebula size to increase with redshift and/or radio power. The
combination of these results suggests that there is a limited but real capacity
for the radio source to influence the properties of the emission line nebulae
at these low redshifts (z < 0.6). Our results are consistent with previous
suggestions that both mechanical and radiant energy are responsible for
generating alignment between the radio source and emission line gas.Comment: 80 pages, 54 figures. Accepted for publication in ApJ
New Distribution Records for Three Species of Notropis (Cypriniformes: Cyprinidae) from Large Rivers of Arkansas
Historical-institutionalist perspectives on the development of the EU budget system
The EU budget has only recently started to feature in theories of European integration. Studies typically adopt a historical-institutionalist framework, exploring notions such as path dependency. They have, however, generally been rather aggregated, or coarse-grained, in their approach. The EU budget has thus been treated as a single entity rather than a series of inter-linked institutions. This paper seeks to address these lacunae by adopting a fine-grained approach. This enables us to emphasize the connections that exist between EU budgetary institutions, in both time and space. We show that the initial set of budgetary institutions was unable, over time, to achieve consistently their treaty-based objectives. In response, rather than reform these institutions at potentially high political cost, additional institutions were layered on top of the extant structures. We thus demonstrate how some EU budgetary institutions have remained unchanged, whilst others have been added or changed over time
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