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981.
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984.
Alexander Horn Ilja Mingareev Alexander Werth Martin Kachel Udo Brenk 《Applied Physics A: Materials Science & Processing》2008,93(1):171-175
Using ultrafast laser radiation glass substrates are welded with glass and silicon plates. The pump beam is focused by a microscope
objective with large NA=0.4 (beam diameter 4 μm) into the glass. After partial absorption of the optical energy, the glass
is heated and melted. Procedures for high-quality welding of glass–glass and glass–silicon substrates with high-repetition
ultra-fast laser radiation have been derived at the repetition rate 700 kHz. The dependencies of the dimension and geometry
of the welding seam on scan velocity, repetition rate and pulse energy have been investigated defining a process window. Adding
a noninterferometric technique for quantitative phase detection with the welding setup, the interaction zone of the welding
seam for the welding partners glass–glass is detected. A change in refractive index is induced by heating and compression
of the glass and has been detected by phase detection up to 2 μs after irradiation with 100 fs time resolution. 相似文献
985.
Steffen A. Föhrenbacher Mirjam J. Krahfuss Ludwig Zapf Dr. Alexandra Friedrich Dr. Nikolai V. Ignat'ev Prof. Dr. Maik Finze Prof. Dr. Udo Radius 《Chemistry (Weinheim an der Bergstrasse, Germany)》2021,27(10):3504-3516
Fluoride abstraction from different types of transition metal fluoride complexes [LnMF] (M=Ti, Ni, Cu) by the Lewis acid tris(pentafluoroethyl)difluorophosphorane (C2F5)3PF2 to yield cationic transition metal complexes with the tris(pentafluoroethyl)trifluorophosphate counterion ( FAP anion, [(C2F5)3PF3]−) is reported. (C2F5)3PF2 reacted with trans-[Ni(iPr2Im)2(ArF)F] (iPr2Im=1,3-diisopropylimidazolin-2-ylidene; ArF=C6F5, 1 a ; 4-CF3-C6F4, 1 b ; 4-C6F5-C6F4, 1 c ) through fluoride transfer to form the complex salts trans-[Ni(iPr2Im)2(solv)(ArF)] FAP ( 2 a - c[solv] ; solv=Et2O, CH2Cl2, THF) depending on the reaction medium. In the presence of stronger Lewis bases such as carbenes or PPh3, solvent coordination was suppressed and the complexes trans-[Ni(iPr2Im)2(PPh3)(C6F5)] FAP ( trans -2 a[PPh3] ) and cis-[Ni(iPr2Im)2(Dipp2Im)(C6F5)] FAP ( cis -2 a[Dipp2Im] ) (Dipp2Im=1,3-bis(2,6-diisopropylphenyl)imidazolin-2-ylidene) were isolated. Fluoride abstraction from [(Dipp2Im)CuF] ( 3 ) in CH2Cl2 or 1,2-difluorobenzene led to the isolation of [{(Dipp2Im)Cu}2]2+2 FAP− ( 4 ). Subsequent reaction of 4 with PPh3 and different carbenes resulted in the complexes [(Dipp2Im)Cu(LB)] FAP ( 5 a – e , LB=Lewis base). In the presence of C6Me6, fluoride transfer afforded [(Dipp2Im)Cu(C6Me6)] FAP ( 5 f ), which serves as a source of [(Dipp2Im)Cu)]+. Fluoride abstraction of [Cp2TiF2] ( 7 ) resulted in the formation of dinuclear [FCp2Ti(μ-F)TiCp2F] FAP ( 8 ) (Cp=η5-C5H5) with one terminal fluoride ligand at each titanium atom and an additional bridging fluoride ligand. 相似文献
986.
Udo Kraatz 《Tetrahedron》1973,29(23):3991-3993
The reaction of γ-butyrolactim- and δ-valerolactim ether with arylisocyanates yields 3-phenylcarbamoyllactim ethers and no 1,3-diazetidinones-(4), which are obtained from ?-caprolactim ether. 3-Phenylcarbamoyl lactams are formed by basic hydrolysis of these derivatives. 相似文献
987.
Aftab M. Hussain Hossain M. Fahad Nirpendra Singh Galo A. Torres Sevilla Udo Schwingenschlögl Muhammad M. Hussain 《固体物理学:研究快报》2014,8(4):332-335
We explore the effectiveness of tin (Sn), by alloying it with silicon, to use SiSn as a channel material to extend the performance of silicon based complementary metal oxide semiconductors. Our density functional theory based simulation shows that incorporation of tin reduces the band gap of Si(Sn). We fabricated our device with SiSn channel material using a low cost and scalable thermal diffusion process of tin into silicon. Our high‐κ/metal gate based multi‐gate‐field‐effect‐transistors using SiSn as channel material show performance enhancement, which is in accordance with the theoretical analysis. (© 2014 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
988.
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990.
Udo Rohde Hendrik Wilkens Rainer Streubel 《Phosphorus, sulfur, and silicon and the related elements》2013,188(1):545-548
Abstract: New lH-diphosphirene and 2,3-dihydro-l,2,3-triphosphete tungsten complexes have been synthesized, by thermal decomposition of different 2H-azaphosphirene complexes in the presence of various phosphaalkynes. Novel phosphorus-carbon cage complexes were obtained, if a pentamethylcyclopentadienyl-substituted 2H-azaphosphirene complex and alkyl-substituted phosphaalkynes were employed. 相似文献