Institution
United States Department of Energy
Government•Washington D.C., District of Columbia, United States•
About: United States Department of Energy is a government organization based out in Washington D.C., District of Columbia, United States. It is known for research contribution in the topics: Coal & Catalysis. The organization has 13656 authors who have published 14177 publications receiving 556962 citations. The organization is also known as: DOE & Department of Energy.
Topics: Coal, Catalysis, Combustion, Oxide, Hydrogen
Papers published on a yearly basis
Papers
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TL;DR: It is proposed that future research in this area should focus on determining the reaction mechanism and kinetics and searching for more cost-effective catalyst and support materials.
Abstract: Methods for removing mercury from flue gas have received increased attention because of recent limitations placed on mercury emissions from coal-fired utility boilers by the U. S. Environmental Protection Agency and various states. A promising method for mercury removal is catalytic oxidation of elemental mercury (Hg0) to oxidized mercury (Hg2+), followed by wet flue gas desulfurization (FGD). FGD cannot remove Hg0, but easily removes Hg2+ because of its solubility in water. To date, research has focused on three broad catalyst areas: selective catalytic reduction catalysts, carbon-based materials, and metals and metal oxides. We review published results for each type of catalyst and also present a discussion on the possible reaction mechanisms in each case. One of the major sources of uncertainty in understanding catalytic mercury oxidation is a lack of knowledge of the reaction mechanisms and kinetics. Thus, we propose that future research in this area should focus on two major aspects: determining the reaction mechanism and kinetics and searching for more cost-effective catalyst and support materials.
492 citations
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Scripps Institution of Oceanography1, University of Barcelona2, Hokkaido University3, United States Department of Energy4, California Institute of Technology5, École normale supérieure de Lyon6, University of Oxford7, University of Genoa8, University of South Florida9, Johns Hopkins University10, University of St Andrews11, Washington University in St. Louis12, University of Milan13, Discovery Institute14, Uppsala University15, Tokyo Metropolitan University16, Tokai University17, University of California, Berkeley18, Okinawa Institute of Science and Technology19, University of Tokyo20, Academy of Sciences of the Czech Republic21, Max Planck Society22, IBM23, University of Maryland, College Park24, University of Toronto25, University of Lausanne26, University of Victoria27, University of Tsukuba28, Kyoto University29, Osaka University30, Nagahama Institute of Bio-Science and Technology31, Sun Yat-sen University32, Juntendo University33, Children's Hospital Oakland Research Institute34
TL;DR: The results indicate that the amphioxus genome is elemental to an understanding of the biology and evolution of nonchordate deuterostomes, invertebrate chordates, and vertebrates.
Abstract: Cephalochordates, urochordates, and vertebrates evolved from a common ancestor over 520 million years ago To improve our understanding of chordate evolution and the origin of vertebrates, we intensively searched for particular genes, gene families, and conserved noncoding elements in the sequenced genome of the cephalochordate Branchiostoma floridae, commonly called amphioxus or lancelets Special attention was given to homeobox genes, opsin genes, genes involved in neural crest development, nuclear receptor genes, genes encoding components of the endocrine and immune systems, and conserved cis-regulatory enhancers The amphioxus genome contains a basic set of chordate genes involved in development and cell signaling, including a fifteenth Hox gene This set includes many genes that were co-opted in vertebrates for new roles in neural crest development and adaptive immunity However, where amphioxus has a single gene, vertebrates often have two, three, or four paralogs derived from two whole-genome duplication events In addition, several transcriptional enhancers are conserved between amphioxus and vertebrates--a very wide phylogenetic distance In contrast, urochordate genomes have lost many genes, including a diversity of homeobox families and genes involved in steroid hormone function The amphioxus genome also exhibits derived features, including duplications of opsins and genes proposed to function in innate immunity and endocrine systems Our results indicate that the amphioxus genome is elemental to an understanding of the biology and evolution of nonchordate deuterostomes, invertebrate chordates, and vertebrates
487 citations
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TL;DR: The Unified Human Gastrointestinal Genome (UHGG) collection, comprising 204,938 nonredundant genomes from 4,644 gut prokaryotes, is presented, providing comprehensive resources for microbiome researchers.
Abstract: Comprehensive, high-quality reference genomes are required for functional characterization and taxonomic assignment of the human gut microbiota. We present the Unified Human Gastrointestinal Genome (UHGG) collection, comprising 204,938 nonredundant genomes from 4,644 gut prokaryotes. These genomes encode >170 million protein sequences, which we collated in the Unified Human Gastrointestinal Protein (UHGP) catalog. The UHGP more than doubles the number of gut proteins in comparison to those present in the Integrated Gene Catalog. More than 70% of the UHGG species lack cultured representatives, and 40% of the UHGP lack functional annotations. Intraspecies genomic variation analyses revealed a large reservoir of accessory genes and single-nucleotide variants, many of which are specific to individual human populations. The UHGG and UHGP collections will enable studies linking genotypes to phenotypes in the human gut microbiome.
485 citations
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TL;DR: In this article, the surface energy per surface atom is proportional to the cohesive energy per bulk atom, and a simple relationship between adsorbate-substrate vibrational stretch frequencies and their desorption energies follows from the universal relationship.
Abstract: Binding-energy-distance relations for metallic systems are shown to exhibit a universal behavior under a simple two-parameter scaling. All currently available ab initio calculations for the cohesion and adhesion of metals, as well as the chemisorption of gas atoms on metal surfaces, are shown to be determined by this single relation. Further, the energetics of diatomic molecules are determined by the same relation, despite the existence of strong volume-dependent forces for metals. These findings suggest a commonality of metallic bonding and a close relationship between molecular and metallic bonding. The universal nature of binding-energy-distance relations implies relations between seemingly disparate physical phenomena. As an example we show that the surface-binding-energy relation can be approximately expressed in terms of the bulk quantities. This leads to an explanation of the well-known empirical result that the surface energy per surface atom is proportional to the cohesive energy per bulk atom. Also, a simple relationship between adsorbate-substrate vibrational stretch frequencies and their desorption energies follows from the universal relationship.
483 citations
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TL;DR: The cement cured at 50 degrees C and 30.3 MPa exhibited a shallower depth of degradation and displayed a well-defined carbonated zone as compared to cement cured under ambient conditions, likely due to smaller, more evenly distributed Ca(OH)2(s) crystals that provide a uniform and effective barrier to CO2 attack.
Abstract: Experiments were conducted to assess the durability of cements in wells penetrating candidate formations for geologic sequestration of CO2. These experiments showed a significant variation in the initial degradation (9 days of exposure) based on the curing conditions. The high-temperature (50 °C) and high-pressure (30.3 MPa) curing environment increased the degree of hydration and caused a change in the microstructure and distribution of the Ca(OH)2(s) phase within the cement. Cement cured at 50 °C and 30.3 MPa (representing sequestration conditions) proved to be more resistant to carbonic acid attack than cement cured at 22 °C and 0.1 MPa. The cement cured at 50 °C and 30.3 MPa exhibited a shallower depth of degradation and displayed a well-defined carbonated zone as compared to cement cured under ambient conditions. This is likely due to smaller, more evenly distributed Ca(OH)2(s) crystals that provide a uniform and effective barrier to CO2 attack.
476 citations
Authors
Showing all 13660 results
Name | H-index | Papers | Citations |
---|---|---|---|
Martin White | 196 | 2038 | 232387 |
Paul G. Richardson | 183 | 1533 | 155912 |
Jie Zhang | 178 | 4857 | 221720 |
Krzysztof Matyjaszewski | 169 | 1431 | 128585 |
Yang Gao | 168 | 2047 | 146301 |
David Eisenberg | 156 | 697 | 112460 |
Marvin Johnson | 149 | 1827 | 119520 |
Carlos Escobar | 148 | 1184 | 95346 |
Joshua A. Frieman | 144 | 609 | 109562 |
Paul Jackson | 141 | 1372 | 93464 |
Greg Landsberg | 141 | 1709 | 109814 |
J. Conway | 140 | 1692 | 105213 |
Pushpalatha C Bhat | 139 | 1587 | 105044 |
Julian Borrill | 139 | 387 | 102906 |
Cecilia Elena Gerber | 138 | 1727 | 106984 |