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901.
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Prof. Dr. Axel G. Griesbeck Dr. Johannes Uhlig Dr. Thomas Sottmann Dr. Lhoussaine Belkoura Prof. Dr. Reinhard Strey 《Chemistry (Weinheim an der Bergstrasse, Germany)》2012,18(50):16161-16165
Pluronic F‐127 hydrogels are highly efficient microenvironments for photochemical reactions, as demonstrated for singlet oxygen reactions of monoalkenes. Nonpolar substrates are localized in the nanosized polymer compartment, which can be visualized by neutron scattering. The efficiency of 1O2 reactions is strongly increased for tiglate derivatives and the regioselectivity of the ene reaction of trisubstituted alkenes is completely switched in comparison with solution phase and inverted in comparison with intrazeolite photo‐oxygenations. 相似文献
903.
M. McCulloch S. K. Fadeff G. M. Mong R. G. Riley D. S. Sklarew B. L. Thomas 《International journal of environmental analytical chemistry》2013,93(2-4):289-293
Abstract DOE Methods for Evaluating Environmental and Waste Management Samples (DOE Methods) is a guidance/methods document to support sampling and analysis activities at DOE sites. DOE Methods is intended to supplement existing guidance documents (e.g., EPA's Test Methods for Evaluating Solid Waste, SW-846), which generally apply to low-level or nonradioactive samples. DOE Methods targets the complexities of DOE radioactive mixed waste and environmental samples. The document contains quality assurance (QA), quality control (QC), safety, sampling, organic analysis, inorganic analysis, and radioanalytical guidance as well as sampling and analytical methods. An addendum is distributed every six months (April and October) with updated guidance and additional methods. DOE Methods provides a vehicle for technology transfer within the environmental restoration (ER) and waste management (WM) (collectively known as EM) community. As DOE Methods evolves, its usefulness and applicability are anticipated to grow to meet the demands of the DOE/EM mission. At the present time, DOE Methods contains methods and guidance information supplied by DOE sites. Because the EM activities in DOE are not unique to the United States, the international environmental community could benefit from the information gathered for the DOE program. This information could provide additional resources for their EM activities. 相似文献
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The synthetic utility of sulfur ylides in orgnic chemistry has been successfully explored over the past several years and has provided an easily accessible route to a number of functional groups,4 including cyclopropanes,5 and optically active epoxides6. 相似文献
906.
A total synthesis of the three anti-coccidial agents WS-5995 A, B, and C by a Diels-Alder route is described. An intramolecular lactonization involving the displacement of a chlorine atom on a naphthoquinone was the key step in the synthesis of A. 相似文献
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