Abstract:
:In this contribution, we consider the advancement of ultrafast electron diffraction and microscopy to cover the attosecond time domain. The concept is centered on the compression of femtosecond electron packets to trains of 15-attosecond pulses by the use of the ponderomotive force in synthesized gratings of optical fields. Such attosecond electron pulses are significantly shorter than those achievable with extreme UV light sources near 25 nm ( approximately 50 eV) and have the potential for applications in the visualization of ultrafast electron dynamics, especially of atomic structures, clusters of atoms, and some materials.
journal_name
Proc Natl Acad Sci U S Aauthors
Baum P,Zewail AHdoi
10.1073/pnas.0709019104subject
Has Abstractpub_date
2007-11-20 00:00:00pages
18409-14issue
47eissn
0027-8424issn
1091-6490pii
0709019104journal_volume
104pub_type
杂志文章abstract::Although advances in microfluidic technology have enabled increasingly sophisticated biosensing and bioassay operations to be performed at the microscale, many of these applications employ such small amounts of charged biomolecules (DNA, proteins, and peptides) that they must first be preconcentrated to a detectable l...
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
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abstract::Peanut or groundnut (Arachis hypogaea L.), a legume of South American origin, has high seed oil content (45-56%) and is a staple crop in semiarid tropical and subtropical regions, partially because of drought tolerance conferred by its geocarpic reproductive strategy. We present a draft genome of the peanut A-genome p...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
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abstract::Replication through a diverse array of DNA lesions occurs by the sequential action of two translesion synthesis (TLS) DNA polymerases (Pols), in which one inserts the nucleotide opposite the lesion and the other carries out the subsequent extension. By extending from the nucleotide inserted by another Pol, Polζ plays ...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
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更新日期:2012-07-31 00:00:00
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
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更新日期:2008-03-04 00:00:00
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.90.7.2784
更新日期:1993-04-01 00:00:00