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101.
Li W Nelson DP Jensen MS Hoerrner RS Cai D Larsen RD Reider PJ 《The Journal of organic chemistry》2002,67(15):5394-5397
3-Pyridylboronic acid was prepared in high yield and bulk quantity from 3-bromopyridine via a protocol of lithium-halogen exchange and "in situ quench". This technique was further studied and evaluated on other aryl halides in the preparation of arylboronic acids. 相似文献
102.
In this paper we present an algorithm for recursively generating orthogonal bivariate polynomials on a discrete set S 2. For this purpose we employ commuting pairs of real symmetric matrices H, K
n×n
to obtain, in a certain sense, a two dimensional Hermitian Lanczos method. The resulting algorithm relies on a recurrence having a slowly growing length. Practical implementation issues an applications are considered. The method can be generalized to compute orthogonal polynomials depending on an arbitrary number of variables. 相似文献
103.
Bearden IG Beavis D Besliu C Blyakhman Y Budick B Bøggild H Chasman C Christensen CH Christiansen P Cibor J Debbe R Enger E Gaardhøje JJ Hagel K Hansen O Holm A Holme AK Ito H Jakobsen E Jipa A Jørdre JI Jundt F Jørgensen CE Karabowicz R Keutgen T Kim EJ Kozik T Larsen TM Lee JH Lee YK Løvhøiden G Majka Z Makeev A McBreen B Mikelsen M Murray M Natowitz J Nielsen BS Norris J Olchanski K Olness J Ouerdane D Płaneta R Rami F Ristea C Röhrich D Samset BH Sandberg D Sanders SJ Sheetz RA Staszel P 《Physical review letters》2002,88(20):202301
We present charged-particle multiplicities as a function of pseudorapidity and collision centrality for the 197Au+197Au reaction at square root[s(NN)] = 200 GeV. For the 5% most central events we obtain dN(ch)/deta/(eta = 0) = 625+/-55 and N(ch)/(-4.7< or =eta < or =4.7) = 4630 +/- 370, i.e., 14% and 21% increases, respectively, relative to square root[s(NN)] = 130 GeV collisions. Charged-particle production per pair of participant nucleons is found to increase from peripheral to central collisions around midrapidity. These results constrain current models of particle production at the highest RHIC energy. 相似文献
104.
Link JM Reyes M Yager PM Anjos JC Bediaga I Göbel C Magnin J Massafferi A de Miranda JM Pepe IM dos Reis AC Carrillo S Casimiro E Cuautle E Sánchez-Hernández A Uribe C Vazquez F Agostino L Cinquini L Cumalat JP O'Reilly B Ramirez JE Segoni I Butler JN Cheung HW Gaines I Garbincius PH Garren LA Gottschalk E Kasper PH Kreymer AE Kutschke R Bianco S Fabbri FL Zallo A Cawlfield C Kim DY Rahimi A Wiss J Gardner R Kryemadhi A Chung YS Kang JS Ko BR Kwak JW Lee KB Park H Alimonti G Boschini M 《Physical review letters》2002,88(16):161801
A high statistics measurement of the Lambda(+)(c) lifetime from the Fermilab fixed-target FOCUS photoproduction experiment is presented. We describe the analysis technique with particular attention to the determination of the systematic uncertainty. The measured value of 204.6 +/- 3.4 (stat) +/- 2.5 (syst) fs from 8034 +/- 122 Lambda(+)(c)-->pK(-)pi(+) decays represents a significant improvement over the present world average. 相似文献
105.
Jack B. Brown Udayan B. Darji Eric P. Larsen 《Proceedings of the American Mathematical Society》1999,127(1):173-182
We investigate the relationships between the notions of a continuous function being monotone on no interval, monotone at no point, of monotonic type on no interval, and of monotonic type at no point. In particular, we characterize the set of all points at which a function that has one of the weaker properties fails to have one of the stronger properties. A theorem of Garg about level sets of continuous, nowhere monotone functions is strengthened by placing control on the location in the domain where the level sets are large. It is shown that every continuous function that is of monotonic type on no interval has large intersection with every function in some second category set in each of the spaces , and .
106.
Christian L. Pedersen Ole Buchardt Sine Larsen Kenneth J. Watson 《Tetrahedron letters》1973,14(24):2195-2198
107.
108.
109.
R.S. Markiewicz H.R. Hart L.V. Interrante J.S. Kasper 《Solid State Communications》1980,35(7):513-517
Both Shubnikov-de Haas and de Haas-van Alphen oscillations are reported for C8nAsF5 (n=1,2, is the stage number). The observed oscillations are interpreted in terms of a tight-binding model for the band structure, and good agreement with both band parameters and effective carrier masses is found. In addition, the effective charge transfer per AsF5 molecule (f=.37 for stage 1, =.41 for stage 2) is in basic agreement with previous determinations. 相似文献
110.