Posts Tagged ‘Research’
Valuation of Ecosystem Services in Institutional Context
Lowell Pritchard Jr.,
Carl Folke,
and Lance Gunderson
INTRODUCTION
As long as we are forced to make choices, we are
doing valuation. But different approaches to valua-
tion are based on qualitatively different assump-
tions. For example, the economics approach to
valuation is based on the ethical principle of con-
sumer sovereignty, and it privileges the kinds of
decisions individuals make in the marketplace. We
accept the economics approach as a useful partial
approach to decision making in relation to ecosys-
temservices if one is interested in what people think
about and want from services; if one believes that
human preferences are the basis for the value of
services; if one accepts the assumption that adding
individual …
Low temperature step-graded InAlAs/GaAs metamorphic buffer layers grown by molecular beam epitaxy
X Z Shang1,3
,SDWu2
, C Liu1
,WXWang2
, LWGuo2
, Q Huang2
and J M Zhou2
1
School of Physics and Technology, Wuhan University, Wuhan 430072, Hubei, People’s
Republic of China
2
State Key Laboratory for Surface Physics, Institute of Physics, Chinese Academy of
Sciences, Beijing 100080, People’s Republic of China
E-mail: xunzhong@acc-lab.whu.edu.cn
Received 8 December 2005
Published 20 April 2006
Online at stacks.iop.org/JPhysD/39/1800
Abstract
Low-temperature step-graded InAlAs metamorphic buffer layers on GaAs
substrate grown by molecular beam epitaxy were investigated. The strain
relaxation and the composition of the top InAlAs layer were determined by
high-resolution triple-axis x-ray diffraction measurements, which show that
the top InAlAs layer is nearly fully relaxed. Surface morphology was
observed by reflection high-energy electron diffraction pattern and …
Oxide Nanoelectrolics
Cheng Cen,
Stefan Thiel,
Jochen Mannhart,
Jeremy Levy
Electronic confinement at nanoscale dimensions remains a central means of science and
technology. We demonstrate nanoscale lateral confinement of a quasi–two-dimensional electron
gas at a lanthanum aluminate–strontium titanate interface. Control of this confinement using an
atomic force microscope lithography technique enabled us to create tunnel junctions and field-effect
transistors with characteristic dimensions as small as 2 nanometers. These electronic devices can be
modified or erased without the need for complex lithographic procedures. Our on-demand
nanoelectronics fabrication platform has the potential for widespread technological application.
Sedimentation processes and new age constraints on rifting stages in Lake Baikal: results of deep-water drilling
Abstract With this paper we present a first attempt to
combine the direct results on lithology, composition
and age dating in the boreholes BDP-93, BDP-96 and
BDP-97 with geological and seismic data from the areas
where those sections were drilled. The sedimentary
environments represented by the BDP boreholes are
markedly different and possess characteristic litholog-
ical features. The results of the deep drilling provide
the essential means for testing …
eLearning Critical Analysis
Over recent years, we’ve been increasingly amazed by technology that provides us with easier ways of accomplishing many things. Doing business, shopping, researching, holding meetings, dating and keeping in touch with our distant friends can now all be done electronically.
Elearning is one of these technological advances that allows us to learn anywhere anytime. Elearning institutions afford us professional instructors and comprehensive online courses over the Internet and can be taken up by using a single computer. These new learning opportunities were brought in by thoughtful people committed in making life easier.
However, there are people who are critical of elearning …
Hypothesis for Cretaceous rifting of east Gondwana caused by subducted slab capture
Bruce P. Luyendyk Institute for Crustal Studies and Department of Geological Sciences, University of California,
Santa Barbara, California 93106-1100
ABSTRACT
In the process of subducted slab capture, a spreading ridge approaches subparallel to
a subduction zone following the trailing edge of a downgoing plate. Eventually the down-
going plate is too young and small to subduct, and spreading stops. The spreading ridge
stalls many tens of kilometres outboard of the subduction zone. The subducted plate welds
to the outboard plate across the dormant spreading center and is captured by it. The
captured plate then acquires the motion of the plate it welded to. In the southwest Pacific
the Pacific-Phoenix …
The automation of Science
Ross D. King,
Jem Rowland,
Stephen G. Oliver,
Michael Young,
Wayne Aubrey,
Emma Byrne,
Maria Liakata,
Magdalena Markham,
Pınar Pir,
Larisa N. Soldatova,
Andrew Sparkes,
Kenneth E. Whelan,
Amanda Clare
The basis of science is the hypothetico-deductive method and the recording of experiments in
sufficient detail to enable reproducibility. We report the development of Robot Scientist “Adam,”
which advances the automation of both. Adam has autonomously generated functional genomics
hypotheses about the yeast Saccharomyces cerevisiae and experimentally tested these hypotheses
by using laboratory automation. We have confirmed Adam’s conclusions through manual
experiments. To describe Adam’s research, we have developed an ontology and logical language.
The resulting formalization involves over 10,000 different research units in a nested treelike
structure, 10 levels …
Al2O3 Physical properties
W. Y. Ching,
Lizhi Ouyang,
Paul Rulis,
and Hongzhi Yao1
Department of Physics, University of Missouri-Kansas City, Kansas City, Missouri 64110, USA
Department of Physics and Mathematics, Tennessee State University, Nashville, Tennessee 37211, USA
Based on the most recently determined noncubic structure for -Al2O3 by Menendez-Proupin and Gutierrez,
a comprehensive list of physical properties is investigated theoretically. These include lattice dynamics and
phonon spectra, elastic constants and bulk structural parameters, electronic structure and interatomic bonding,
optical properties, and x-ray absorption near-edge structure XANES spectra. Compared to similar calcula-
tions of -Al2O3, we find a smaller lowest zone-center vibrational mode at 97.6 cm−1
, a lower heat capacity,
a smaller bulk modulus, and …