Institution
California Institute of Technology
Education•Pasadena, California, United States•
About: California Institute of Technology is a education organization based out in Pasadena, California, United States. It is known for research contribution in the topics: Galaxy & Redshift. The organization has 57649 authors who have published 146691 publications receiving 8620287 citations. The organization is also known as: Caltech & Cal Tech.
Topics: Galaxy, Redshift, Population, Star formation, Stars
Papers published on a yearly basis
Papers
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TL;DR: In this paper, the most important experimental results from the first three years of nucleus-nucleus collision studies at RHIC were reviewed, with emphasis on results of the STAR experiment.
2,750 citations
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TL;DR: The design and observation of two-dimensional crystalline forms of DNA that self-assemble from synthetic DNA double-crossover molecules that create specific periodic patterns on the nanometre scale are reported.
Abstract: Molecular self-assembly presents a `bottom-up' approach to the fabrication of objects specified with nanometre precision. DNA
molecular structures and intermolecular interactions are particularly
amenable to the design and synthesis of complex molecular objects. We
report the design and observation of two-dimensional crystalline forms
of DNA that self-assemble from synthetic DNA double-crossover
molecules. Intermolecular interactions between the structural units are
programmed by the design of `sticky ends' that associate according to
Watson-Crick complementarity, enabling us to create specific periodic
patterns on the nanometre scale. The patterned crystals have been
visualized by atomic force microscopy.
2,713 citations
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TL;DR: In this article, it was shown that at the base of the crack in the direction of its prolongation, the principal stresses are equal, thus tending toward a two-dimensional (two-dimensional) hydrostatic tension.
Abstract: In an earlier paper it was suggested that a knowledge of
the elastic-stress variation in the neighborhood of an
angular corner of an infinite plate would perhaps be of
value in analyzing the stress distribution at the base of a
V-notch. As a part of a more general study, the specific
case of a zero-angle notch, or crack, was carried out to
supplement results obtained by other investigators. This
paper includes remarks upon the antisymmetric, as well
as symmetric, stress distribution, and the circumferential
distribution of distortion strain-energy density. For the
case of a symmetrical loading about the crack, it is shown
that the energy density is not a maximum along the direction
of the crack hut is one third higher at an angle ± cos^(-1)
(1/3); i.e., approximately ±70 deg. It is shown that at the
base of the crack in the direction of its prolongation, the
principal stresses are equal, thus tending toward a state of
(two-dimensional) hydrostatic tension. As the distance
from the point of the crack increases, the distortion strain
energy increases, suggesting the possibility of yielding
ahead of the crack as well as ±70 deg to the sides. The
maximum principal tension stress occurs on ±60 deg rays.
For the antisymmetrical stress distribution the distortion
strain energy is a relative maximum along the crack and
60 per cent lower ± 85 deg to the sides.
2,693 citations
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01 Jan 1965TL;DR: The evaluation of the amount of differences between two organisms as derived from sequences in structural genes or in their polypeptide translation is likely to lead to quantities different from those obtained on the basis of observations made at any other, higher level of biological integration.
Abstract: Publisher Summary Informational macromolecules, or semantides, play a unique role in determining the properties of living matter in the perspectives that differ by the magnitude of time required for the processes involved—the short-timed biochemical reaction, the medium-timed ontogenetic event, and the long-timed evolutionary event. Although the slower processes should be broken down into linked faster processes, if one loses sight of the slower processes one also loses the links between the component faster processes. The relative importance of the contributions to evolution of changes in functional properties of polypeptides through their structural modification on the one hand, and of changes in the timing and the rate of synthesis of these polypeptides on the other hand, constitutes a problem that justifies the study of evolution at the level of informational macromolecules. The evaluation of the amount of differences between two organisms as derived from sequences in structural genes or in their polypeptide translation is likely to lead to quantities different from those obtained on the basis of observations made at any other, higher level of biological integration.
2,677 citations
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TL;DR: BSCF is presented as a new cathode material for reduced-temperature SOFC operation and demonstrated that BSCF is ideally suited to ‘single-chamber’ fuel-cell operation, where anode and cathode reactions take place within the same physical chamber.
Abstract: Fuel cells directly and efficiently convert chemical energy to electrical energy. Of the various fuel cell types, solid-oxide fuel cells (SOFCs) combine the benefits of environmentally benign power generation with fuel flexibility. However, the necessity for high operating temperatures (800–1,000 °C) has resulted in high costs and materials compatibility challenges. As a consequence, significant effort has been devoted to the development of intermediate-temperature (500–700 °C) SOFCs. A key obstacle to reduced-temperature operation of SOFCs is the poor activity of traditional cathode materials for electrochemical reduction of oxygen in this temperature regime2. Here we present Ba_(0.5_Sr_(0.5)Co_(0.8)Fe_(0.2)O_(3-delta) (BSCF) as a new cathode material for reduced-temperature SOFC operation. BSCF, incorporated into a thin-film doped ceria fuel cell, exhibits high power densities (1,010 mW cm^(-2) and 402 mW cm^(-2) at 600 °C and 500 °C, respectively) when operated with humidified hydrogen as the fuel and air as the cathode gas. We further demonstrate that BSCF is ideally suited to 'single-chamber' fuel-cell operation, where anode and cathode reactions take place within the same physical chamber. The high power output of BSCF cathodes results from the high rate of oxygen diffusion through the material. By enabling operation at reduced temperatures, BSCF cathodes may result in widespread practical implementation of SOFCs.
2,672 citations
Authors
Showing all 58155 results
Name | H-index | Papers | Citations |
---|---|---|---|
Eric S. Lander | 301 | 826 | 525976 |
Donald P. Schneider | 242 | 1622 | 263641 |
George M. Whitesides | 240 | 1739 | 269833 |
Yi Chen | 217 | 4342 | 293080 |
David Baltimore | 203 | 876 | 162955 |
Edward Witten | 202 | 602 | 204199 |
George Efstathiou | 187 | 637 | 156228 |
Michael A. Strauss | 185 | 1688 | 208506 |
Jing Wang | 184 | 4046 | 202769 |
Ruedi Aebersold | 182 | 879 | 141881 |
Douglas Scott | 178 | 1111 | 185229 |
Hyun-Chul Kim | 176 | 4076 | 183227 |
Phillip A. Sharp | 172 | 614 | 117126 |
Timothy M. Heckman | 170 | 754 | 141237 |
Zhenan Bao | 169 | 865 | 106571 |