5,069 research outputs found
Till Death Do Us Part: A Comparative Law Approach to Justifying Lethal Self-Defense by Battered Women
Till death do us part : a comparative law approach to justifying lethal self- defense by battered women. - In: Duke journal of comparative & international law. 1. 1991. S. 169-21
Semiconducting polymers for gas detection
Conjugated polyenes, and polyesters containing phthalocyanine in their backbone, were synthesized. These polymers were characterized by chemical analysis, thermogravimetric analysis, spectral analysis, and X-ray diffraction studies for crystallinity, as well as for their film-forming capability and gas/polymer interactions. Most of the polymers were relatively insensitive to water vapor up to 50 percent relative humidity, but the polyester/phthalocyanine (iron) polymer was relatively insensitive up to 100 percent RH. On the other hand, poly(p-dimethylaminophenylacetylene) was too conductive at 100 percent RH. Of the gases tested, the only ones that gave any evidence of interacting with the polymers were SO2, NOx, HCN and NH3. Poly(imidazole)/thiophene responded to each of these gases at all relative humidities, while the other polymers gave varying response, depending upon the RH. Thus, since most of these gases were electron-accepting, the electron-donating character of poly(imidazole)/thiophene substantiates the concept of electronegativity being the operating principle for interaction effects. Of the six polymers prepared, poly(imidazole)/thiophene first showed a very good response to smoldering cotton, but it later became nonresponsive; presumably due to oxidation effects
Synthesis and evaluation of polymers for use in early warning fire alarm devices
Conjugated polyacetylene polymers and one condensation polyene, all containing a high degree of conjugated unsaturation, were synthesized. These polymers were characterized by chemical analysis and by thermogravimetric analysis, as well as for their film-forming capability and gas/polymer interactions. It was found that those that had a high degree of conjugated unsaturation and had resonance - stabilizing groups were very thermally stable to 200 C, e.g., poly(dicyanoacetylene), poly(ethynylferrocene) and poly(phenylacetylene); while those with labile moieties, such as poly(p-formamidophenylacetylene), among others, suffered some degradation when heated in air. When subjected to gas/polymer interaction effects, the greatest change in electrical conductance was observed when ammonia was used as the gas and poly(p-nitrophenylacetylene) was the detector. Other polymers showed similar behavior. For example, poly(ethynylcarborane), considered to be an electron acceptor also showed a change in electrical conductance when exposed to ammonia, while poly(ethynylpyridine) and poly(ethylidenepyridazine) responded to carbon monoxide. However, for "fire gases" (gases from smoldering cotton), poly(ethynylferrocene) was the most responsive. Thus, the concept of polymers with different electronegativities forming charge-transfer complexes with different gases was found to be operable
Dynamic sampling schemes for optimal noise learning under multiple nonsmooth constraints
We consider the bilevel optimisation approach proposed by De Los Reyes,
Sch\"onlieb (2013) for learning the optimal parameters in a Total Variation
(TV) denoising model featuring for multiple noise distributions. In
applications, the use of databases (dictionaries) allows an accurate estimation
of the parameters, but reflects in high computational costs due to the size of
the databases and to the nonsmooth nature of the PDE constraints. To overcome
this computational barrier we propose an optimisation algorithm that by
sampling dynamically from the set of constraints and using a quasi-Newton
method, solves the problem accurately and in an efficient way
Miniature Optical Atomic Clock: Stabilization of a Kerr Comb Oscillator
Mechanical clocks consist of a pendulum and a clockwork that translates the
pendulum period to displayed time. The most advanced clocks utilize optical
transitions in atoms in place of the pendulum and an optical frequency comb
generated by a femtosecond laser as the clockwork. The comb must be stabilized
at two points along its frequency spectrum: one with a laser to lock a comb
line to a transition in the atom, and another through self referencing to
stabilize the frequency interval between the comb lines. This approach requires
advanced techniques, so optical atomic clocks are currently laboratory devices
in specialized labs. In this paper we leverage unique properties of Kerr comb
oscillators for realization of optical atomic clocks in miniature form factors.
In particular, we describe a clock based on D1 transition of 87Rb that fits in
the palm of the hand, and can be further miniaturized to chip scale.Comment: 4 pages, 4 figure
Arm Position During Ambulatory Blood Pressure Monitoring: A Review of the Evidence and Clinical Guidelines
Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/106696/1/jch12255.pd
Topological structures of adiabatic phase for multi-level quantum systems
The topological properties of adiabatic gauge fields for multi-level
(three-level in particular) quantum systems are studied in detail. Similar to
the result that the adiabatic gauge field for SU(2) systems (e.g. two-level
quantum system or angular momentum systems, etc) have a monopole structure, the
curvature two-forms of the adiabatic holonomies for SU(3) three-level and SU(3)
eight-level quantum systems are shown to have monopole-like (for all levels) or
instanton-like (for the degenerate levels) structures.Comment: 15 pages, no figures. Accepted by J.Phys.
A Parametrization of Bipartite Systems Based on SU(4) Euler Angles
In this paper we give an explicit parametrization for all two qubit density
matrices. This is important for calculations involving entanglement and many
other types of quantum information processing. To accomplish this we present a
generalized Euler angle parametrization for SU(4) and all possible two qubit
density matrices. The important group-theoretical properties of such a
description are then manifest. We thus obtain the correct Haar (Hurwitz)
measure and volume element for SU(4) which follows from this parametrization.
In addition, we study the role of this parametrization in the Peres-Horodecki
criteria for separability and its corresponding usefulness in calculating
entangled two qubit states as represented through the parametrization.Comment: 23 pages, no figures; changed title and abstract and rewrote certain
areas in line with referee comments. To be published in J. Phys. A: Math. and
Ge
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