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991.
T.R. Saito N. Saito K. Starosta J. Beller N. Pietralla H.J. Wollersheim D.L. Balabanski A. Banu R.A. Bark T. Beck F. Becker P. Bednarczyk K.-H. Behr G. Benzoni P.G. Bizzeti C. Boiano A. Bracco S. Brambilla A. Brünle A. Bürger L. Caceres F. Camera F.C.L. Crespi P. Doornenbal A.B. Garnsworthy H. Geissel J. Gerl M. Górska J. Grebosz G. Hagemann J. Jolie M. Kavatsyuk O. Kavatsyuk T. Koike I. Kojouharov N. Kurz J. Leske G. Lo Bianco A. Maj S. Mallion S. Mandal M. Maliage T. Otsuka C.M. Petrache Zs. Podolyak W. Prokopowicz G. Rainovski P. Reiter A. Richard H. Schaffner 《Physics letters. [Part B]》2008
992.
Adamson P Andreopoulos C Arms KE Armstrong R Auty DJ Ayres DS Baller B Barnes PD Barr G Barrett WL Becker BR Belias A Bernstein RH Bhattacharya D Bishai M Blake A Bock GJ Boehm J Boehnlein DJ Bogert D Bower C Buckley-Geer E Cavanaugh S Chapman JD Cherdack D Childress S Choudhary BC Cobb JH Coleman SJ Culling AJ de Jong JK Dierckxsens M Diwan MV Dorman M Dytman SA Escobar CO Evans JJ Harris EF Feldman GJ Frohne MV Gallagher HR Godley A Goodman MC Gouffon P Gran R Grashorn EW Grossman N Grzelak K 《Physical review letters》2008,101(13):131802
This Letter reports new results from the MINOS experiment based on a two-year exposure to muon neutrinos from the Fermilab NuMI beam. Our data are consistent with quantum-mechanical oscillations of neutrino flavor with mass splitting |Deltam2| = (2.43+/-0.13) x 10(-3) eV2 (68% C.L.) and mixing angle sin2(2theta) > 0.90 (90% C.L.). Our data disfavor two alternative explanations for the disappearance of neutrinos in flight: namely, neutrino decays into lighter particles and quantum decoherence of neutrinos, at the 3.7 and 5.7 standard-deviation levels, respectively. 相似文献
993.
The crystal structures of the title compounds, 1,3‐di‐tert‐butyl‐2,3‐dihydro‐1H‐1,3,2‐diazasilol‐2‐ylidene, C10H20N2Si ( 1 ) and 1,3‐di‐tert‐butyl‐2,2‐dichloro‐1,3‐diaza‐2‐sila‐4‐cyclopentene, C10H20N2SiCl2 ( 3 ) were solved and are reported. Compound ( 1 ) crystallized in space group P mmn and each molecule has a mirror plane, which bisects the C‐C backbone of the N‐C‐C‐N framework. Compound ( 1 ) was also found to have a 2‐fold twin component. In compound ( 3 ) the space group P 21/m results with the mirror plane passing through the N‐C‐C‐N backbone. We compare these structures with the gas phase determination previously reported for ( 1 ) and the incomplete single crystal data for ( 3 ). (© 2004 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
994.
995.
P. Becker 《Crystal Research and Technology》2001,36(2):119-126
The origin of reported twin domains of LiGeBO4 was investigated by methods of thermal analysis. The twins were found to result from a phase transition which occurs 2‐3 K below the peritectic decomposition of the compound. Large single crystals of LiGeBO4 were grown by an improved growth method using the top‐seeding technique. Linear optical properties (refractive indices between 404 nm and 2325 nm and unpolarized absorption spectrum) as a basis for nonlinear optical investigations were determined. Unfortunately, LiGeBO4 is not phase matchable. 相似文献
996.
The preparation of pure CdF2 and of CdF2 crystals by the Bridgman method is described in detail. The aggressivity of the melt requires special precautions concerning the crucible material and the protecting gas. By zone melting the spectroanalytical detection limit of impurities (≈ 1 ppm) is attained. Some remarks on the mechanical, thermal, and chemical properties of the crystals and on their further processing are given. 相似文献
997.
S. Bornmann E. Glauche P. Grnert R. Hergt C. Becker 《Crystal Research and Technology》1974,9(8):895-904
In this paper a summary is given on the reproducible preparation of large, nearly defectless yttrium iron garnet single crystals (YIG) grown in fluxes by slowly cooling with accelerated crucible rotation (ACRT) and local bottom cooling. The surface morphology of the growth faces is discussed with regard to the growth mechanism. By different methods the crystals are characterized regarding their lattice defects (impurities, growth striations, dislocations, inclusions). Ferromagnetic resonance measurements in the X-band at polished, inclusionsfree discs show that the linewidth ΔH of any crystals from different runs are less than 0.45 Oe. 相似文献
998.
999.
1000.
Peter Becker Daniel L. Priebbenow Ramona Pirwerdjan Carsten Bolm 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2014,126(1):273-275
Acylsilanes are known to undergo a 1,2‐silicon‐to‐oxygen migration under thermal or photochemical conditions to form siloxycarbenes. However, there are few reports regarding the application of siloxycarbenes in organic synthesis and surprisingly, their reaction with C C double or triple bonds remains virtually unexplored. To facilitate such a study, previously inaccessible aromatic acylsilanes containing an ortho‐tethered C C double bond were identified as suitable substrates. To access these key intermediates, we developed a new synthetic method utilizing a rhodium‐catalyzed oxidative Heck‐type olefination involving the application of an acylsilane moiety as a directing group. When exposed to visible‐light irradiation, the ortho‐olefinated acylsilanes underwent a smooth intramolecular cyclization process to afford valuable indanone derivatives in quantitative yields. This result paves the way for the development of new transformations involving siloxycarbene intermediates. 相似文献