1,168,341 research outputs found
Transparent switchboard
A tin oxide coating is formed on a plate of glass and the coating is then etched away from the glass in thin lines to form separate electrical conductors which extend to one end of the plate and connect to either a vertical (column) or horizontal (row) position sensing SCR circuit. A thin transparent insulating coating is formed over the oxide layer except at selected touch points which are positioned in a matrix pattern of vertical columns and horizontal rows. Touching one of these points with a finger bridges the thin line between adjacent conductors to activate trigger circuits in the particular row and column sensing circuits associated with the point touched. The row and column sensing circuits are similar and are powered with a low frequency, ac voltage source. The source for the row circuits is 180 out of phase with the source for the column circuits so that one circuit acts as ground for the other during half of the supply voltage cycle. The signals from the sensing circuits are input to a logic circuit which determines the presence of a valid touch, stores a binary matrix number associated with the touched point, signals a computer of the presence of a stored number and prevents storage of a new number before receiving an enable signal from the computer
Transparent polymeric laminates
Laminate prepared from epoxy-boroxine and phenolphthalein polycarbonate has high mechanical strength at elevated temperature and is resistant to impact, fire, and high-energy thermal radiation. Polycarbonate is prepared by reaction of phenolphthalein with phosgene in presence of amine catalyst and immiscible organic solvent phase
Transparent Perfect Mirror
A mirror that reflects light fully and yet is transparent appears
paradoxical. Current so-called transparent or "one-way" mirrors are not
perfectly reflective and thus can be distinguished from a standard mirror.
Constructing a transparent "perfect" mirror has profound implications for
security, privacy, and camouflage. However, such a hypothetical device cannot
be implemented in a passive structure. We demonstrate here a transparent
perfect mirror in a non-Hermitian configuration: an active optical cavity where
a certain prelasing gain extinguishes Poynting's vector at the device entrance.
At this threshold, all vestiges of the cavity's structural resonances are
eliminated and the device presents spectrally flat unity-reflectivity, thus,
becoming indistinguishable from a perfect mirror when probed optically across
the gain bandwidth. Nevertheless, the device is rendered transparent by virtue
of persisting amplified transmission resonances. We confirm these predictions
in two photonic realizations: a compact integrated active waveguide and a
macroscopic all-optical-fiber system.Comment: The paper is highlighted in Nature Photonics:
http://www.nature.com/nphoton/journal/v11/n6/full/nphoton.2017.90.html The
supplementary data is available in:
http://pubs.acs.org/doi/suppl/10.1021/acsphotonics.7b0005
Transparency in International Investment Law: The Good, the Bad, and the Murky
How transparent is the international investment law regime, and how transparent should it be? Most studies approach these questions from one of two competing premises. One camp maintains that the existing regime is opaque and should be made completely transparent; the other finds the regime sufficiently transparent and worries that any further transparency reforms would undermine the regime’s essential functioning. This paper explores the tenability of these two positions by plumbing the precise contours of transparency as an overarching norm within international investment law. After defining transparency in a manner befitting the decentralized nature of the regime, the paper identifies international investment law’s key transparent, semi-transparent, and non-transparent features. It underscores that these categories do not necessarily map onto prevailing normative judgments concerning what might constitute good, bad, and murky transparency practices. The paper then moves beyond previous analyses by suggesting five strategic considerations that should factor into future assessments of whether and how particular aspects of the regime should be rendered more transparent. It concludes with a tentative assessment of the penetration, recent evolution, and likely trajectory of transparency principles within the contemporary international investment law regime
Transparent dense sodium
Under pressure, metals exhibit increasingly shorter interatomic distances.
Intuitively, this response is expected to be accompanied by an increase in the
widths of the valence and conduction bands and hence a more pronounced
free-electron-like behaviour. But at the densities that can now be achieved
experimentally, compression can be so substantial that core electrons overlap.
This effect dramatically alters electronic properties from those typically
associated with simple free-electron metals such as lithium and sodium, leading
in turn to structurally complex phases and superconductivity with a high
critical temperature. But the most intriguing prediction - that the seemingly
simple metals Li and Na will transform under pressure into insulating states,
owing to pairing of alkali atoms - has yet to be experimentally confirmed. Here
we report experimental observations of a pressure-induced transformation of Na
into an optically transparent phase at 200 GPa (corresponding to 5.0-fold
compression). Experimental and computational data identify the new phase as a
wide bandgap dielectric with a six-coordinated, highly distorted
double-hexagonal close-packed structure. We attribute the emergence of this
dense insulating state not to atom pairing, but to p-d hybridizations of
valence electrons and their repulsion by core electrons into the lattice
interstices. We expect that such insulating states may also form in other
elements and compounds when compression is sufficiently strong that atomic
cores start to overlap strongly.Comment: Published in Nature 458, 182-185 (2009
Towards transparent telepresence
It is proposed that the concept of transparent telepresence can be closely approached through high fidelity technological mediation. It is argued that the matching of the system capabilities to those of the human user will yield a strong sense of immersion and presence at a remote site. Some applications of such a system are noted. The concept is explained and critical system elements are described together with an overview of some of the necessary system specifications
Color Transparent GPDs?
The relation between GPD's and color transparency is explored. The discovery
of color transparency in pionic diffractive dissociation reactions allows us to
make specific predictions for the behavior of the pion generalized parton
distribution, and provide a further test of any model of the pion form factor.Comment: 12 pages, 3 figure
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