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A method to remove Ammonia using a Proton-Conducting Ceramic Membrane
An apparatus and method for decomposing NH{sub 3}. A fluid containing NH{sub 3} is passed in contact with a tubular membrane that is a homogeneous mixture of a ceramic and a first metal, with the ceramic being selected from one or more of a cerate having the formula of M' Ce{sub 1-x} M''O{sub 3-{delta}}, zirconates having the formula M'Zr{sub 1-x} M''3-{delta}, stannates having the formula M'Sn{sub 1-x}M''O{sub 3}-{delta}, where M' is a group IIA metal, M'' is a dopant metal of one or more of Ca, Y, Yb, In, Nd, Gd or mixtures thereof and {delta} is a variable depending on the concentration of dopant and is in the range of from 0.001 to 0.5, the first metal is a group VIII or group IB element selected from the group consisting of Pt, Ag, Pd, Fe, Co, Cr, Mn, V, Ni, Au, Cu, Rh, Ru and mixtures thereof. The tubular membrane has a catalytic metal on the side thereof in contact with the fluid containing NH{sub 3} which is effective to cause NH{sub 3} to decompose to N{sub 2} and H{sub 2}. When the H{sub 2} contacts the membrane, H{sup +} ions are formed which pass through the membrane driving the NH{sub 3} decomposition toward completion
Complex regeneration responses of eight tree species to partial harvest in mixedwood forests of northeastern North America
Ecosystem-based forest management associated with partial harvesting (PH) is intended to balance ecological
and economic values of sustainable forest management. The potential for delayed growth response and elevated
mortality of advance regeneration following PH remains a critical concern, and may present a barrier to more
widespread implementation of this approach. We used 835 permanent continuous forest inventory plots to
examine the rate and time course of species-specific regeneration growth and mortality of eight tree species in
the first fifteen years following operational partial harvests in the mixed-species forests of Maine, United States.
We aimed to provide a quantitative understanding on how regeneration of different species responded to PH in
terms of growth and mortality. In addition, we evaluated how the patterns and magnitudes of growth and
mortality responses developed over time, if these responses occur gradually or suddenly, and if the patterns of the
responses were persistent. We found that the response magnitude, temporal trajectories of responses, and the
length of initial lag-period largely varied across species, PH treatments, and the variables examined. For sapling
diameter growth, paper birch (Betula papyrifera Marshall) and red maple (Acer rubrum L.) showed immediate
responses to high-intensity PH, while a five-year lag-period was observed in balsam fir (Abies balsamea (L.) Mill.),
American beech (Fagus grandifolia Ehrh.), red spruce (Picea rubens Sarg.) and eastern hemlock (Tsuga canadensis
(L.) Carri`ere) and a 10-year lag period in northern white-cedar (Thuja occidentalis L.). The initial increase in
sapling mortality was observed in balsam fir, American beech, red maple and northern white-cedar, but not in
other species. Sapling survival reached a stable state irrespective of species after the initial five-years following
harvests. In partially harvested stands, identifying preharvest conditions related to postharvest density, growth,
and mortality was complex and interacted with time since harvest. Our results suggest that broad application of
PH only results in species-specific gains, losses, and delays in regeneration responses within mixed-species
stands. Future research should consider PH in combination with other treatments to initiate immediate responses
to a wider range of species.We thank to US Forest Service Forest Inventory and Analysis (FIA)
for access to the long-term database. Funding was provided by the
United States National ScienceFoundation’s Center for Advanced
Forestry Systems (#1915078) and R-II Track-2 FEC (#1920908) and
from NSRC Alliance (ALLRP 557166 - 20)
Quantum cobwebs: Universal entangling of quantum states
Entangling an unknown qubit with one type of reference state is generally
impossible. However, entangling an unknown qubit with two types of reference
states is possible. To achieve this, we introduce a new class of states called
zero sum amplitude (ZSA) multipartite, pure entangled states for qubits and
study their salient features. Using shared-ZSA state, local operation and
classical communication we give a protocol for creating multipartite entangled
states of an unknown quantum state with two types of reference states at remote
places. This provides a way of encoding an unknown pure qubit state into a
multiqubit entangled state. We quantify the amount of classical and quantum
resources required to create universal entangled states. This is possibly a
strongest form of quantum bit hiding with multiparties.Comment: Invited talk in II Winter Institute on FQTQO: Quantum Information
Processing, held at S. N. Bose Center for Basic Science, Kolkata, during Jan
2-11, 2002. (To appear in Pramana-J. of Physics, 2002.
Scientific Objectives of Einstein Telescope
The advanced interferometer network will herald a new era in observational astronomy. There is a very strong science case to go beyond the advanced detector network and build detectors that operate in a frequency range from 1Hz to 10kHz, with sensitivity a factor 10 better in amplitude. Such detectors will be able to probe a range of topics in nuclear physics, astronomy, cosmology and fundamental physics, providing insights into many unsolved problems in these areas
Physics, Astrophysics and Cosmology with Gravitational Waves
Gravitational wave detectors are already operating at interesting sensitivity
levels, and they have an upgrade path that should result in secure detections
by 2014. We review the physics of gravitational waves, how they interact with
detectors (bars and interferometers), and how these detectors operate. We study
the most likely sources of gravitational waves and review the data analysis
methods that are used to extract their signals from detector noise. Then we
consider the consequences of gravitational wave detections and observations for
physics, astrophysics, and cosmology.Comment: 137 pages, 16 figures, Published version
<http://www.livingreviews.org/lrr-2009-2
Sensitivity Studies for Third-Generation Gravitational Wave Observatories
Advanced gravitational wave detectors, currently under construction, are
expected to directly observe gravitational wave signals of astrophysical
origin. The Einstein Telescope, a third-generation gravitational wave detector,
has been proposed in order to fully open up the emerging field of gravitational
wave astronomy. In this article we describe sensitivity models for the Einstein
Telescope and investigate potential limits imposed by fundamental noise
sources. A special focus is set on evaluating the frequency band below 10Hz
where a complex mixture of seismic, gravity gradient, suspension thermal and
radiation pressure noise dominates. We develop the most accurate sensitivity
model, referred to as ET-D, for a third-generation detector so far, including
the most relevant fundamental noise contributions.Comment: 13 pages, 7 picture
Scientific Potential of Einstein Telescope
Einstein gravitational-wave Telescope (ET) is a design study funded by the
European Commission to explore the technological challenges of and scientific
benefits from building a third generation gravitational wave detector. The
three-year study, which concluded earlier this year, has formulated the
conceptual design of an observatory that can support the implementation of new
technology for the next two to three decades. The goal of this talk is to
introduce the audience to the overall aims and objectives of the project and to
enumerate ET's potential to influence our understanding of fundamental physics,
astrophysics and cosmology.Comment: Conforms to conference proceedings, several author names correcte
Scientific Objectives of Einstein Telescope
The advanced interferometer network will herald a new era in observational
astronomy. There is a very strong science case to go beyond the advanced
detector network and build detectors that operate in a frequency range from 1
Hz-10 kHz, with sensitivity a factor ten better in amplitude. Such detectors
will be able to probe a range of topics in nuclear physics, astronomy,
cosmology and fundamental physics, providing insights into many unsolved
problems in these areas.Comment: 18 pages, 4 figures, Plenary talk given at Amaldi Meeting, July 201
Sensitivity to Gravitational Waves from Compact Binary Coalescences Achieved during LIGO's Fifth and Virgo's First Science Run
We summarize the sensitivity achieved by the LIGO and Virgo gravitational
wave detectors for compact binary coalescence (CBC) searches during LIGO's
fifth science run and Virgo's first science run. We present noise spectral
density curves for each of the four detectors that operated during these
science runs which are representative of the typical performance achieved by
the detectors for CBC searches. These spectra are intended for release to the
public as a summary of detector performance for CBC searches during these
science runs.Comment: 12 pages, 5 figure
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