Abstract:
:In many of their compounds the transition metals have covalence 9, forming nine bonds with use of nine hybrid spd bond orbitals. A set of maximum-valence single-bond radii is formulated for use in these compounds. These radii are in reasonably good agreement with observed bond lengths. Quadruple bonds between two transition metal atoms are about 50 pm (iron-group atoms) or 55 pm (palladium and platinum-group atoms) shorter than single bonds. This amount of shortening corresponds to four bent single bonds with the best set of bond angles, 79.24 degrees and 128.8 degrees .
journal_name
Proc Natl Acad Sci U S Aauthors
Pauling Ldoi
10.1073/pnas.72.10.3799keywords:
subject
Has Abstractpub_date
1975-10-01 00:00:00pages
3799-801issue
10eissn
0027-8424issn
1091-6490journal_volume
72pub_type
杂志文章abstract::The amino acid sequence for chicken smooth muscle myosin light chain kinase (smMLCK) was deduced from a full-length cDNA. This has allowed definition of both the complete sequence of the inactive 64-kDa proteolytic fragment, which contains the pseudosubstrate autoregulatory sequence, and of the active 61-kDa Ca2+/calm...
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
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更新日期:1996-07-09 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
pub_type: 杂志文章
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更新日期:2013-06-04 00:00:00
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更新日期:2010-07-20 00:00:00
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pub_type: 杂志文章
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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
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更新日期:2001-01-16 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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更新日期:2010-04-06 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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更新日期:2003-06-24 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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更新日期:2014-08-19 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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更新日期:2001-03-13 00:00:00
abstract::This introduction to the Special Feature presents the context for science during the Deepwater Horizon oil spill response, summarizes how scientific knowledge was integrated across disciplines and statutory responsibilities, identifies areas where scientific information was accurate and where it was not, and considers...
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:2006-03-28 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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更新日期:2016-05-03 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:1999-09-14 00:00:00
abstract::Viral glycoproteins mediate entry of enveloped viruses into cells and thus play crucial roles in infection. In herpesviruses, a complex of two viral glycoproteins, gH and gL (gH/gL), regulates membrane fusion events and influences virion cell tropism. Human cytomegalovirus (HCMV) gH/gL can be incorporated into two dif...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
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更新日期:2015-04-07 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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更新日期:2008-06-03 00:00:00
abstract::Graphene oxide (GO), the main precursor of graphene-based materials made by solution processing, is known to be very stiff. Indeed, it has a Young's modulus comparable to steel, on the order of 300 GPa. Despite its very high stiffness, we show here that GO is superflexible. We quantitatively measure the GO bending rig...
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.1605121113
更新日期:2016-10-04 00:00:00