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排序方式: 共有1004条查询结果,搜索用时 15 毫秒
31.
Bonner BE Buchanan JA Clement JM Corcoran MD Krishna NM Kruk JW Lincoln DW Miettinen HE Mutchler GS Nessi-Tedaldi F Nessi M Phillips GC Roberts JB Stevenson PM Tonse SR White JL Chung SU Etkin A Fernow RC Protopopescu SD Willutzki H Hallman T Madansky L Pinsky LS 《Physical review letters》1989,62(14):1591-1594
32.
Abelev BI Aggarwal MM Ahammed Z Anderson BD Arkhipkin D Averichev GS Bai Y Balewski J Barannikova O Barnby LS Baudot J Baumgart S Belaga VV Bellingeri-Laurikainen A Bellwied R Benedosso F Betts RR Bhardwaj S Bhasin A Bhati AK Bichsel H Bielcik J Bielcikova J Bland LC Blyth SL Bombara M Bonner BE Botje M Bouchet J Brandin AV Bravar A Burton TP Bystersky M Cadman RV Cai XZ Caines H Calderón de la Barca Sánchez M Callner J Catu O Cebra D Chajecki Z Chaloupka P Chattopadhyay S Chen HF Chen JH 《Physical review letters》2007,99(11):112301
We present first measurements of the phi-meson elliptic flow (v2(pT)) and high-statistics pT distributions for different centralities from radical sNN=200 GeV Au+Au collisions at RHIC. In minimum bias collisions the v2 of the phi meson is consistent with the trend observed for mesons. The ratio of the yields of the Omega to those of the phi as a function of transverse momentum is consistent with a model based on the recombination of thermal s quarks up to pT approximately 4 GeV/c, but disagrees at higher momenta. The nuclear modification factor (R CP) of phi follows the trend observed in the K S 0 mesons rather than in Lambda baryons, supporting baryon-meson scaling. These data are consistent with phi mesons in central Au+Au collisions being created via coalescence of thermalized s quarks and the formation of a hot and dense matter with partonic collectivity at RHIC. 相似文献
33.
The Soreq Applied Research Accelerator Facility (SARAF): Overview,research programs and future plans
Israel Mardor Ofer Aviv Marilena Avrigeanu Dan Berkovits Adi Dahan Timo Dickel Ilan Eliyahu Moshe Gai Inbal Gavish-Segev Shlomi Halfon Michael Hass Tsviki Hirsh Boaz Kaiser Daniel Kijel Arik Kreisel Yonatan Mishnayot Ish Mukul Ben Ohayon Michael Paul Amichay Perry Hitesh Rahangdale Jacob Rodnizki Guy Ron Revital Sasson-Zukran Asher Shor Ido Silverman Moshe Tessler Sergey Vaintraub Leo Weissman 《The European Physical Journal A - Hadrons and Nuclei》2018,54(5):91
34.
Magnetic susceptibility measurements of strain-free dilute alloys of Eu in Mg indicate that the Eu is predominantly divalent with ground state. The analysis indicates no solid solubility of Eu in Mg. 相似文献
35.
Ron Wright 《International Journal of Theoretical Physics》1977,16(8):567-573
A projection-valued state is defined to be a completely orthoadditive map from the projections on one Hilbert space into the projections on another Hilbert space, which preserves the unit. Any such mapping is shown to have the formP U
1(P 11)U
1
–1
U
2(P 12)U
2
–1
, whereU
1 is unitary andU
2 is antiunitary, generalizing Wigner's theorem on symmetry transformations. A physical interpretation is given and the relation to quantum logic is discussed.The contents of this paper are a portion of the author's dissertation at the University of Massachusetts at Amherst. 相似文献
36.
37.
38.
The following conjecture may have never been explicitly stated, but seems to have been floating around: if the vertex set
of a graph with maximal degree Δ is partitioned into sets V
i
of size 2Δ, then there exists a coloring of the graph by 2Δ colors, where each color class meets each V
i
at precisely one vertex. We shall name it the strong 2Δ-colorability conjecture. We prove a fractional version of this conjecture. For this purpose, we prove a weighted generalization of a theorem of Haxell,
on independent systems of representatives (ISR’s). En route, we give a survey of some recent developments in the theory of
ISR’s.
The research of the first author was supported by grant no 780/04 from the Israel Science Foundation, and grants from the
M. & M. L. Bank Mathematics Research Fund and the fund for the promotion of research at the Technion.
The research of the third author was supported by the Sacta-Rashi Foundation. 相似文献
39.
Ron Aharoni Eli Berger Agelos Georgakopoulos Amitai Perlstein 《Journal of Combinatorial Theory, Series B》2011,101(1):1-17
We prove a strong version of the Max-Flow Min-Cut theorem for countable networks, namely that in every such network there exist a flow and a cut that are “orthogonal” to each other, in the sense that the flow saturates the cut and is zero on the reverse cut. If the network does not contain infinite trails then this flow can be chosen to be mundane, i.e. to be a sum of flows along finite paths. We show that in the presence of infinite trails there may be no orthogonal pair of a cut and a mundane flow. We finally show that for locally finite networks there is an orthogonal pair of a cut and a flow that satisfies Kirchhoff's first law also for ends. 相似文献
40.
The potent Diels-Alder diene, phencyclone, 1, reacts with N-pentafluorophenylmaleimide, 2, to form an adduct, 3, characterized by 1H, 13C, and 19F NMR at 300, 75 and 282 MHz, respectively. The one-dimensional (1D) and two-dimensional (2D) 1H and 13C NMR spectra of 3 at ambient temperatures imply a slow exchange limit (SEL) regime with respect to rotation of the unsubstituted bridgehead phenyl groups about severely hindered C(sp2)-C(sp3) bonds. Major non-bonded interactions are expected between the ortho protons of the C6H5 groups and H-1, 8 of the phenanthrenoid moiety of 3. 19F 1D and 2D (COSY) NMR spectra show that the SEL regime also obtains for rotation about the N-C6F5 bond of 3, with five separate fluorine signals seen, consistent with a preferred conformation in which the C6F5 may lie roughly perpendicular to the plane of the pyrrolidinedione moiety, and may be in the mirror symmetry plane of 3. The results are considered relevant to hindered aryl rotations in numerous Pharmaceuticals. Selected spectral data for 2 and precursors are also presented. 相似文献