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101.
Hong H Gates PJ Staunton J Stinear T Cole ST Leadlay PF Spencer JB 《Chemical communications (Cambridge, England)》2003,(22):2822-2823
LC-MSn analysis of mycolactone toxin from extracts of Mycobacterium ulcerans has shown that minor co-metabolites, including two previously unreported, differ structurally from mycolactone only in a small portion of the polyketide side-chain. 相似文献
102.
Chung P Ajitanand NN Alexander JM Anderson M Best D Brady FP Case T Caskey W Cebra D Chance JL Cole B Crowe K Das A Draper JE Gilkes ML Gushue S Heffner M Hirsch AS Hjort EL Huo L Justice M Kaplan M Keane D Kintner JC Klay J Krofcheck D Lacey RA Lauret J Lisa MA Liu H Liu YM McGrath R Milosevich Z Odyniec G Olson DL Panitkin SY Pinkenburg C Porile NT Rai G Ritter HG Romero JL Scharenberg R Schroeder L Srivastava B Stone NT Symons TJ Wienold T Witt R Whitfield J Wood L Zhang WN;E Collaboration 《Physical review letters》2001,86(12):2533-2536
Directed flow measurements for Lambda hyperons are presented and compared to those for protons produced in the same Au+Au collisions (2A, 4A, and 6A GeV; b<5-6 fm). The measurements indicate that Lambda hyperons flow consistently in the same direction but with smaller magnitudes. A strong positive flow [for Lambdas] has been predicted in calculations which include the influence of the Lambda-nucleon potential. The experimental flow ratio Lambda/p is in qualitative agreement with expectations (approximately 2/3) from the quark counting rule at 2A GeV but is found to decrease with increasing beam energy. 相似文献
103.
Thompson R Dytman S Kim KY Mueller J Adams GS Amaryan MJ Anciant E Anghinolfi M Asavapibhop B Auger T Audit G Avakian H Barrow S Battaglieri M Beard K Bektasoglu M Bertozzi W Bianchi N Biselli A Boiarinov S Bonner BE Briscoe WJ Brooks W Burkert VD Calarco JR Capitani G Carman DS Carnahan B Cole PL Coleman A Connelly J Cords D Corvisiero P Crabb D Crannell H Cummings J Day D Degtyarenko PV Demirchyan RA Dennis LC Deppman A De Sanctis E De Vita R Dhuga KS Djalali C Dodge GE Doughty D 《Physical review letters》2001,86(9):1702-1706
New cross sections for the reaction e p-->e p eta are reported for total center of mass energy W = 1.5--1.86 GeV and invariant momentum transfer Q2 = 0.25--1.5 (GeV/c)(2). This large kinematic range allows extraction of important new information about response functions, photocouplings, and eta N coupling strengths of baryon resonances. Newly observed structure at W approximately 1.65 GeV is shown to come from interference between S and P waves and can be interpreted with known resonances. Improved values are derived for the photon coupling amplitude for the S11(1535) resonance. 相似文献
104.
E. F. Jones P. M. Gore J. H. Hamilton A. V. Ramayya A. P. de Lima R. S. Dodder J. Kormicki J. K. Hwang C. J. Beyer X. Q. Zhang S. J. Zhu G. M. Ter-Akopian Yu. Ts. Oganessian A. V. Daniel J. O. Rasmussen I. Y. Lee J. D. Cole M. W. Drigert W.-C. Ma 《Physics of Atomic Nuclei》2001,64(7):1157-1164
The levels in 162Gd were identified in spontaneous fission studies. Its transition energies are remarkably similar to those in 160Gd. From that work, an analysis of yrast bands in even-even proton to neutron-rich Ba to Pb nuclei led to the discovery of a new phenomenon, shifted identical bands (SIB). SIBs are yrast bands in neighboring nuclei (a, b) with moments of inertia which are identical when shifted by a constant amount κ, so J 1a (1+κ)=J 1b , from 2+ to 8+ and higher to 16+. Out of over 700 comparisons, 55 SIBs were found from stable to the most neutron-rich Ce-W nuclei with $\left| {\bar k} \right|$ between 1.5% and 13%, where the spread in κ is less than ±1%, and only four identical bands ( $\bar k \cong 0$ ). As examples, we found for 158Sm-160Gd, $\bar k = \left( { - 3.2_{ - 0.2}^{ + 0.1} } \right)\%$ (where the ± is the total spread in κ from ?3.1 to ?3.4); 156Nd-160Gd, (?10.6 ?0.2 +0.4 )%; 158Sm-160Sm, (3.4 ?0.3 +0.5 )%. The J 1 values were fitted to a variable moment of inertia model with parameters J 0 and C whose values correlate with the SIB J 1 values. The SIBs are not correlated either with deformation or with the N p N n product of the IBA model. 相似文献
105.
Liu H Ajitanand NN Alexander J Anderson M Best D Brady FP Case T Caskey W Cebra D Chance J Cole B Crowe K Das A Draper J Gilkes M Gushue S Heffner M Hirsch A Hjort E Huo L Justice M Kaplan M Keane D Kintner J Klay J Krofcheck D 《Physical review letters》2000,84(24):5488-5492
Using the large acceptance Time Projection Chamber of experiment E895 at Brookhaven, measurements of collective sideward flow in Au+Au collisions at beam energies of 2A, 4A, 6A, and 8A GeV are presented in the form of in-plane transverse momentum
and the first Fourier coefficient of azimuthal anisotropy v(1). These measurements indicate a smooth variation of sideward flow as a function of beam energy. The data are compared with four nuclear transport models which have an orientation towards this energy range. All four exhibit some qualitative trends similar to those found in the data, although none show a consistent pattern of agreement within experimental uncertainties. 相似文献
106.
Production of metallic ion beams in support of the experimental program at the Coupled Cyclotron Facility at the NSCL required the development of ion sputtering feed of metallic molybdenum,nickel,uranium, and zirconium for use with the ARTEMIS ion source.The production of high intensity lower to medium charge state ions required high material consumption,posing some significant difficulties in reliable long term beam stability.Resultant and ongoing hardware and technique developments to resolve these difficulties will be presented in this poster along with interesting effects of the ion source solenoid field polarity on the sputtering process. 相似文献
107.
108.
Kevin P. Cole David Mitchell M. Austin Carr James R. Stout Matthew D. Belvo 《Tetrahedron: Asymmetry》2009,20(11):1262-1266
A route for the synthesis of (S,S)-7-amino-5-methyl-5H-dibenzo[b,d]azepin-6(7H)-one hydrochloride is disclosed. The synthesis includes a Friedel–Crafts alkylation to form the seven-membered ring and a highly efficient classical resolution. Additional studies on the enantiopure material showed the amine to be highly resistant to racemization, which led us to investigate the unexpected stability. We propose that the inherent axial chirality contained in the dibenzazepinone works to produce an interesting chirality transfer mechanism, which accounts for the observed robustness of the stereocenter. This previously unrecognized stereochemical element exists within this specific class of molecules, and they should be drawn in a manner which displays the axial chirality. 相似文献
109.
V. Henriques U. Klausen J. Race K. L. Zirm J. Benedict W. Zimmermann J. Robert S. W. Cole S. L. Leiboff B. S. Kahn B. Matsumoto L. Ambard F. Schmid T. Teorell S. Balachowski B. Bruns A. Fujita S. Kasahara F. Serio S. Fiandaca K. Lang O. Manasse H. Müller H. v. Pechmann G. Schmidt R. Willstätter H. Kraut O. Erbacher J. Sacks A. C. Jvy J. P. Burgess und J. E. Vandolah 《Fresenius' Journal of Analytical Chemistry》1933,93(1-2):64-80
Ohne Zusammenfassung 相似文献
110.