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141.
Abe F Albrow MG Amendolia SR Amidei D Antos J Anway-Wiese C Apollinari G Areti H Auchincloss P Austern M Azfar F Azzi P Bacchetta N Badgett W Bailey MW Bao J de Barbaro P Barbaro-Galtieri A Barnes VE Barnett BA Bartalini P Bauer G Baumann T Bedeschi F Behrends S Belforte S Bellettini G Bellinger J Benjamin D Benlloch J Bensinger J Benton D Beretvas A Berge JP Bertolucci S Bhatti A Biery K Binkley M Bird F Bisello D Blair RE Blocker C Bodek A Bolognesi V Bortoletto D Boswell C Boulos T 《Physical review letters》1994,73(2):225-231
142.
Benton L. Duncan 《Linear algebra and its applications》2007,422(1):67-76
We study a class of matrix function algebras, here denoted T+(Cn). We introduce a notion of point derivations, and classify the point derivations for certain finite dimensional representations of T+(Cn). We use point derivations and information about n×n matrices to show that every T+(Cn)-valued derivation on T+(Cn) is inner. 相似文献
143.
Jessica Benton 《Linear algebra and its applications》2006,412(1):30-38
Associated with an m × n matrix with entries 0 or 1 are the m-vector of row sums and n-vector of column sums. In this article we study the set of all pairs of these row and column sums for fixed m and n. In particular, we give an algorithm for finding all such pairs for a given m and n. 相似文献
144.
C. D. Bowman J. D. Bowman P. Herczeg J. Szymanski V. W. Yuan J. M. Anaya R. Mortensen H. Postma P. P. J. Delheij O. K. Baker C. R. Gould D. G. Haase G. E. Mitchell N. R. Roberson X. Zhu A. B. McDonald D. Benton B. Tippens T. E. Chupp 《Hyperfine Interactions》1988,43(1-4):117-126
A facility for polarized epithermal neutrons of high intensity is set up at the Los Alamos National Laboratory for parityviolation
and time reversal experiments at neutron resonances over a wide range of neutron energies. The beam is polarized with the
aid of a polarized proton target used as a neutronspin filter. Total cross section measurements as well as capture gamma-ray
experiments will be carried out. The main features of this system will be discussed. 相似文献
145.
146.
David G. Agresti Richard V. Morris Edward L. Wills Tad D. Shelfer Marsha M. Pimperl Ming-Hung Shen Benton C. Clark Brian D. Ramsey 《Hyperfine Interactions》1992,72(1-3):283-298
We describe a combined backscatter Mössbauer spectrometer and X-ray fluorescence analyzer (BaMS/XRF) instrument suitable for planetary missions to the surfaces of Mars (MESUR Program), the Moon, asteroids, or other solid solar-system objects. The BaMS/XRF instrument is designed to be capable of concurrent analysis of a sample for its elemental abundances (XRF) and for the mineralogy of its iron-bearing phases (BaMS) without any sample preparation. 相似文献
147.
Luke A. Johnson Alice Dunbabin Jennifer C. R. Benton Robert J. Mart Rudolf K. Allemann 《Angewandte Chemie (International ed. in English)》2020,59(22):8486-8490
Non‐natural terpenoids offer potential as pharmaceuticals and agrochemicals. However, their chemical syntheses are often long, complex, and not easily amenable to large‐scale production. Herein, we report a modular chemoenzymatic approach to synthesize terpene analogues from diphosphorylated precursors produced in quantitative yields. Through the addition of prenyl transferases, farnesyl diphosphates, (2E,6E)‐FDP and (2Z,6Z)‐FDP, were isolated in greater than 80 % yields. The synthesis of 14,15‐dimethyl‐FDP, 12‐methyl‐FDP, 12‐hydroxy‐FDP, homo‐FDP, and 15‐methyl‐FDP was also achieved. These modified diphosphates were used with terpene synthases to produce the unnatural sesquiterpenoid semiochemicals (S)‐14,15‐dimethylgermacrene D and (S)‐12‐methylgermacrene D as well as dihydroartemisinic aldehyde. This approach is applicable to the synthesis of many non‐natural terpenoids, offering a scalable route free from repeated chain extensions and capricious chemical phosphorylation reactions. 相似文献
148.
Determination of f(s)/f(d) for 7 TeV pp collisions and measurement of the B0→D-K+ branching fraction
Aaij R Adeva B Adinolfi M Adrover C Affolder A Ajaltouni Z Albrecht J Alessio F Alexander M Alkhazov G Alvarez Cartelle P Alves AA Amato S Amhis Y Amoraal J Anderson J Appleby RB Gutierrez OA Arrabito L Artamonov A Artuso M Aslanides E Auriemma G Bachmann S Back JJ Bailey DS Balagura V Baldini W Barlow RJ Barschel C Barsuk S Barter W Bates A Bauer C Bauer T Bay A Bediaga I Belous K Belyaev I Ben-Haim E Benayoun M Bencivenni G Benson S Benton J Bernet R Bettler MO van Beuzekom M Bien A Bifani S 《Physical review letters》2011,107(21):211801
The relative abundance of the three decay modes B(0)→D(-)K(+), B(0)→D(-)π(+), and B(s)(0)→D(s)(-)π(+) produced in 7 TeV pp collisions at the LHC is determined from data corresponding to an integrated luminosity of 35 pb(-1). The branching fraction of B(0)→D(-)K(+) is found to be B(B(0)→D(-)K(+)) = (2.01 ± 0.18(stat) ± 0.14(syst)) × 10(-4). The ratio of fragmentation fractions f(s)/f(d) is determined through the relative abundance of B(s)(0)→D(s)(-)π(+) to B(0)→D(-)K(+) and B(0)→D(-)π(+), leading to f(s)/f(d) = 0.253 ± 0.017 ± 0.017 ± 0.020, where the uncertainties are statistical, systematic, and theoretical, respectively. 相似文献
149.
Benton CM Lim CK Moniz C Jones DJ 《Rapid communications in mass spectrometry : RCM》2011,25(24):3749-3757
An ultra-high-performance liquid chromatography/electrospray ionisation tandem mass spectrometry system is described for the separation and characterisation of uroporphyrinogen, heptacarboxylic acid porphyrinogen, hexacarboxylic acid porphyrinogen, pentacarboxylic acid porphyrinogen and coproporphyrinogen. The separation was carried out on a 100 mm × 2.1 mm Thermo-Hypersil BDS column (2.4 μm average particle size) by gradient elution with a mixture of acetonitrile, methanol and 1 mol/L aqueous ammonium acetate buffer, pH 5.16, as eluent. The fragmentation pattern of each compound was established by collision-induced dissociation tandem mass spectrometry. The most characteristic fragmentation was ring opening at one of the four methylene bridges of the protonated porphyrinogen molecule followed by further cleavages of methylene bridges linking the four pyrrole rings at various points to give product ions with methylenepyrrolenine, methylene-dipyrrolenine and methylene-tripyrrolenine structures. 相似文献