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91.
C. Rathika Thaya Kumari P. Jayaprakash M. Nageshwari M. Peer Mohamed P. Sangeetha 《Molecular Crystals and Liquid Crystals》2017,658(1):186-197
A nonlinear optical material benzoyl valine (BV) was synthesized by the technique of slow evaporation process at room temperature. The single crystal X ray diffraction analysis evince that crystal corresponds to acentric space group P21 with monoclinic system. The diverse optical properties assured an elevated transparency in BV crystal. Photoluminescence profile revealed the suitability of crystal for fabricating violet lasers. The Laser damage threshold and the dielectric behavior of the grown crystal were analyzed to indicate its practical applications. The second and third order nonlinear optical measurements were studied to prove its potentiality in the domain of nonlinear optical applications. 相似文献
92.
Schmidt S Bork P Dandekar T 《Journal of chemical information and computer sciences》2002,42(2):405-407
The WEB tool "AnDom" assigns to a given protein sequence all experimentally determined structural domains contained within it, including multidomain and large proteins. The server uses profile specific matrices from custom generated multiple sequence alignments of all known SCOP domains (SCOP version 1.50). Prediction time is short allowing numerous applications for structural genomics including investigation of complex eucaryotic protein families. The WWW server is at http://www.bork.embl-heidelberg.de/AnDom, and profiles can be downloaded at ftp.bork.embl-heidelberg.de/pub/users/ schmidt/AnDom. 相似文献
93.
Distribution semigroups and abstract Cauchy problems 总被引:3,自引:0,他引:3
Peer Christian Kunstmann 《Transactions of the American Mathematical Society》1999,351(2):837-856
We present a new definition of distribution semigroups, covering in particular non-densely defined generators. We show that for a closed operator in a Banach space the following assertions are equivalent: (a) generates a distribution semigroup; (b) the convolution operator has a fundamental solution in where denotes the domain of supplied with the graph norm and denotes the inclusion ; (c) generates a local integrated semigroup. We also show that every generator of a distribution semigroup generates a regularized semigroup.
94.
Peer Christian Kunstmann Zeljko Strkalj 《Proceedings of the American Mathematical Society》2003,131(7):2081-2088
Let be the generator of a symmetric submarkovian semigroup in . In this note we show that on the operator admits a bounded functional calculus on the sector for each \psi_p^*$"> with
This improves a result due to M. Cowling. We apply our result to obtain maximal regularity for parabolic equations and evolutionary integral equations.
This improves a result due to M. Cowling. We apply our result to obtain maximal regularity for parabolic equations and evolutionary integral equations.
95.
Nicoletti M Bremer M Kirsch P O'Hagan D 《Chemical communications (Cambridge, England)》2007,(47):5075-5077
The synthesis of the stereospecifically fluorinated difluoro- and trifluoro- rac-3 and rac-4 is described where the fluorine atoms are positioned adjacent/vicinal to each other and the physical characteristics of these candidate liquid crystals including negative dielectric anisotropy are measured and rationalised. 相似文献
96.
Thomas Billert Rainer Beckert Jörg Brandenburg Peer Fehling Manfred Döring Helmar Görls Peter Langer 《Journal of heterocyclic chemistry》1999,36(3):627-633
The reaction of pyrido[1,2-a]pyrazines 1 with nitroso compounds 2 provides pyridyl substituted 1,2,4-triazinones 4 via a domino reaction which involves a cycloaddition and a ring transformation reaction. The intermediate and regioselective formed oxadiazines 4′ were trapped by complexation yielding the (CO)4Mo-complex 5. Derivatives of diazene such as N-phenyltriazolindione 6a , phthalazinedione 6b or esters of azodicarboxylic acid 6c-6f reacted with 1 to give different derivatives of 1,2,4-triazine 7a-f . The use of oxygen gave oxadiazinones 8 . 相似文献
97.
PZT Aerogels: Sol-Gel Derived Piezoelectric 3-3 Composites 总被引:1,自引:0,他引:1
Löbmann Peer Glaubitt Walther Geis Stefan 《Journal of Sol-Gel Science and Technology》2000,19(1-3):145-148
Ultrasonic transducers with low acoustic impedances are required for applications in gaseous media. In porous piezoelectrics the pore volume acts as a second medium of a solid-gas composite and thus lowers the overall acoustic impedance. Lead zirconate titanate (PbZr.53Ti.47O3, PZT) aerogels were prepared by sol-gel processing and supercritical drying in isopropanol. Prefiring at 400°C in air and subsequent thermal treatment in saturated PbO-atmosphere results in phase transformation to PZT (perovskite phase), grain growth and aerogel densification. In this paper the densification of this new class of piezoelectric material at temperatures above 600°C is described. Porosities were measured as a function of sintering time and temperature. Changes in the microstructure were characterized by scanning electron microscopy. Dielectric measurements are presented. 相似文献
98.
99.
100.
Tim Granath Peer Löbmann Karl Mandel 《Particle & Particle Systems Characterization》2021,38(3):2000307
Oxidative precipitation is a facile synthesis method to obtain ferromagnetic iron oxide nanoparticles from ferrous salts—with unexplored potential. The concentration of base and oxidant alone strongly affects the particle's structure and thus their magnetic properties despite the same material, magnetite (Fe3O4), is obtained when precipitated with potassium hydroxide (KOH) from ferrous sulfate (FeSO4) and treated with potassium nitrate (KNO3) at appropriate temperature. Depending on the potassium hydroxide and potassium nitrate concentrations, it is possible to obtain a series of different types of either single crystals or mesocrystals. The time-dependent mesocrystal evolution can be revealed via electron microscopy and provides insights into the process of oriented attachment, yielding faceted particles, showing a facet-dependent reactivity. It is found that it is the nitrate and hydroxide concentration that influences the ligand exchange process and thus the crystallization pathways. The presence of sulfate ions contributes to the mesocrystal evolution as well, as sulfate apparently hinders further crystal fusion, as revealed via infrared spectroscopy. Finally, it is found that nitrite, as one possible and ecologically highly relevant reduction product occurring in nature in context with iron, only evolves if the reaction is quantitative. 相似文献