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71.
Jutta KocklerAuthor VitaeMichael OelgemöllerAuthor Vitae Sherryl RobertsonAuthor VitaeBeverley D. GlassAuthor Vitae 《Journal of Photochemistry and Photobiology, C: Photochemistry Reviews》2012,13(1):91-110
Sunscreens were originally designed to include mainly UVB-filters. Because of the deeper penetration of UVA light, causing photoaging and DNA damage, there has been a shift towards broad spectrum sunscreens. These broad spectrum sunscreens now include both UVA- and UVB-filters and other ingredients which possess antioxidant activity. Although sunscreens are regulated in most countries, photostability testing is not mandatory. Because of the ability of sunscreen ingredients to absorb UV-light and the complexity of most of these formulations, which may include more than one UV-filter, antioxidants and other formulation excipients, it is important that their photostability in combination is determined. 相似文献
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α-Functionalized 2-Methyl Phenylphosphines, 2-(HE? CH2)? C6H4? PH2 (E = O, NR, PH) II. Coordination Behaviour with Metal Carbonyles of Cr, Mo, W The preparation of different carbonyl substituted coordination compounds (M: Cr, Mo, W) of the phosphines 2-(HE? CH2)C6H4? PH2 (E = O, NPh, PH) is described. In one case, after deprotonation of a PH2 group a phosphine/phosphide migration of a W(CO)5 fragment is detected. 相似文献
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Baldur Föhlisch Robert Flogaus Jutta Oexle Angelika Schädel 《Tetrahedron letters》1984,25(17):1773-1776
1,1-Dichloro- and 1,3-dichloro-2-alkanones react with 2-methylfuran in the presence of lithium perchlorate/triethylamine to form 2-chloro-1-methyl-8-oxabicyclo [3.2.1]oct-6-ene-3-ones predominantly. 相似文献
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Background
The present experiments were designed to test how the linguistic feature of case is processed in Japanese by native and non-native listeners. We used a miniature version of Japanese as a model to compare sentence comprehension mechanisms in native speakers and non-native learners who had received training until they had mastered the system. In the first experiment we auditorily presented native Japanese speakers with sentences containing incorrect double nominatives and incorrect double accusatives, and with correct sentences. In the second experiment we tested trained non-natives with the same material. Based on previous research in German we expected an N400-P600 biphasic ERP response with specific modulations depending on the violated case and whether the listeners were native or non-native. 相似文献76.
Jutta Mitas 《Order》1991,8(2):115-132
Although the jump number problem for partially ordered sets in NP-complete in general, there are some special classes of posets for which polynomial time algorithms are known.Here we prove that for the class of interval orders the problem remains NP-complete. Moreover we describe another 3/2-approximation algrithm (two others have been developed already by Felsner and Syslo, respectively) by using a polynomial time subgraph packing algorithm. 相似文献
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