Institution
United States Environmental Protection Agency
Government•Washington D.C., District of Columbia, United States•
About: United States Environmental Protection Agency is a government organization based out in Washington D.C., District of Columbia, United States. It is known for research contribution in the topics: Population & Environmental exposure. The organization has 13873 authors who have published 26902 publications receiving 1191729 citations. The organization is also known as: EPA & Environmental Protection Agency.
Papers published on a yearly basis
Papers
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TL;DR: The functionalized magnetically retrievable catalysts or nanocatalysts that are increasingly being used in catalysis, green chemistry and pharmaceutically significant reactions are summarized in this review.
Abstract: Surface functionalization of nano-magnetic nanoparticles is a well-designed way to bridge the gap between heterogeneous and homogeneous catalysis. The introduction of magnetic nanoparticles (MNPs) in a variety of solid matrices allows the combination of well-known procedures for catalyst heterogenization with techniques for magnetic separation. Magnetite is a well-known material, also known as ferrite (Fe3O4), and can be used as a versatile support for functionalization of metals, organocatalysts, N-heterocyclic carbenes, and chiral catalysts. It is used as a support for important homogeneous catalytically active metals such as Pd, Pt, Cu, Ni, Co, Ir, etc. to obtain stable and magnetically recyclable heterogeneous catalysts. Homogeneous organocatalysts can be successfully decorated with linkers/ligands on the surface of magnetite or alternatively the organocatalysts can be directly immobilized on the surface of magnetite. The functionalized magnetically retrievable catalysts or nanocatalysts that are increasingly being used in catalysis, green chemistry and pharmaceutically significant reactions are summarized in this review.
1,057 citations
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TL;DR: In this paper, the theoretical background of modeling the gap fraction and the leaf inclination distribution is presented and different techniques used to derive leaf area index (LAI) and leaf inclination angle from gap fraction measurements are reviewed.
1,052 citations
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Colorado State University1, National Park Service2, University of Rhode Island3, United States Environmental Protection Agency4, Emory University5, University of Maryland, College Park6, University of North Carolina at Chapel Hill7, University of Wisconsin-Madison8, Duke University9, The Nature Conservancy10
TL;DR: The scope of the thresholds concept in ecological science is defined and methods for identifying and investigating thresholds using a variety of examples from terrestrial and aquatic environments, at ecosystem, landscape and regional scales are discussed.
Abstract: An ecological threshold is the point at which there is an abrupt change in an ecosystem quality, property or phenomenon, or where small changes in an environmental driver produce large responses in the ecosystem. Analysis of thresholds is complicated by nonlinear dynamics and by multiple factor controls that operate at diverse spatial and temporal scales. These complexities have challenged the use and utility of threshold concepts in environmental management despite great concern about preventing dramatic state changes in valued ecosystems, the need for determining critical pollutant loads and the ubiquity of other threshold-based environmental problems. In this paper we define the scope of the thresholds concept in ecological science and discuss methods for identifying and investigating thresholds using a variety of examples from terrestrial and aquatic environments, at ecosystem, landscape and regional scales. We end with a discussion of key research needs in this area.
1,049 citations
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TL;DR: Investigation within watersheds of South-East Queensland, Australia found the presence of 28 antibiotics in three hospital effluents, five wastewater treatment plants (WWTPs), six rivers and a drinking water storage catchment was investigated, with further evidence that WWTPs are an important source of antibiotics to streams.
1,010 citations
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TL;DR: In this article, the authors focus on the use of nano-catalysis for green chemistry development including the strategy of using microwave heating with nanocatalysis in benign aqueous reaction media which offers an extraordinary synergistic effect with greater potential than these three components in isolation.
1,005 citations
Authors
Showing all 13926 results
Name | H-index | Papers | Citations |
---|---|---|---|
Joel Schwartz | 183 | 1149 | 109985 |
Timothy A. Springer | 167 | 669 | 122421 |
Chien-Jen Chen | 128 | 655 | 66360 |
Matthew W. Gillman | 126 | 529 | 55835 |
J. D. Hansen | 122 | 975 | 76198 |
Dionysios D. Dionysiou | 116 | 675 | 48449 |
John P. Giesy | 114 | 1162 | 62790 |
Douglas W. Dockery | 105 | 244 | 57461 |
Charles P. Gerba | 102 | 692 | 35871 |
David A. Savitz | 99 | 572 | 32947 |
Stephen Polasky | 99 | 354 | 59148 |
Judith C. Chow | 96 | 427 | 32632 |
Diane R. Gold | 95 | 443 | 30717 |
Scott L. Zeger | 95 | 377 | 78179 |
Rajender S. Varma | 95 | 672 | 37083 |