排序方式: 共有27条查询结果,搜索用时 15 毫秒
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Corden VA Duhme-Klair AK Hostachy S Perutz RN Reddig N Becker HC Hammarström L 《Inorganic chemistry》2011,50(3):1105-1115
A heteroditopic ligand H(2)-L consisting of a dihydroxybenzene (catechol)-unit linked via an amide bond to a pyridyl-unit and its methyl-protected precursor Me(2)-L were synthesized, characterized, and their photophysical properties investigated. The three accessible protonation states of the ligand, H(3)-L(+), H(2)-L, and H-L(-), showed distinct (1)H NMR, absorption and emission spectroscopic characteristics that allow pH-sensing. The spectroscopic signatures obtained act as a guide to understand the signaling mechanism of the luminescent pH and molybdate sensor [Re(bpy)(CO)(3)(H(2)-L)](+). It was found that upon deprotonation of the 2-hydroxy group of H(2)-L, a ligand-based absorption band emerges that overlaps with the Re(dπ)→bpy metal-to-ligand charge transfer (MLCT) band of the sensor, reducing the quantum yield for emission on excitation in the 370 nm region. In addition, deprotonation of the catechol-unit leads to quenching of the emission from the Re(dπ)→bpy (3)MLCT state, consistent with photoinduced electron transfer from the electron-rich, deprotonated catecholate to the Re-based luminophore. Finally, reaction of 2 equiv of [Re(bpy)(CO)(3)(H(2)-L)](+) with molybdate was shown to give the zwitterionic Mo(VI) complex [MoO(2){Re(CO)(3)(bpy)(L)}(2)], as confirmed by electrospray ionization (ESI) mass spectrometry and X-ray crystallography. The crystal structure determination revealed that two fully deprotonated sensor molecules are bound via their oxygen-donors to a cis-dioxo-MoO(2) center. 相似文献
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M.J. Corden J.D. Dowell D. Eastwood J. Garvey R.J. Homer M. Jobes I.R. Kenyon T. McMahon R.J. Vallance P.M. Watkins J.A. Wilson J. Gago M. Jung P. Sonderegger D. Treille P.L. Woodworth V. Eckardt J. Fent K.C.T.O. Sumorok 《Physics letters. [Part B]》1977,68(1):96-100
Measurements have been made of relative production cross sections of the by π±, K±, p and p? at 39.5 GeV/c incident on copper. production rates from π?, K? and p? are similar. The relative particle/anti-particle production cross sections for x>0 are , σ(K+)/σ(K?)=(0.85±0.5) and . The small p/p? cross section ratio disagrees with models of J/ψ production by gluon amalgamation. 相似文献
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M.J. Corden G.F. Cox D.P. Kelsey C.A. Lawrence P.M. Watkins O. Hamon J. Le Guyader J.M. Levy G.W. London 《Nuclear Physics B》1979,155(1):13-38
The differential and channel cross sections have been measured for the reactions KL0p → KS0p and KL0p → Λ0π+ in nine energy intervals in the c.m. range 1605 to 1910 MeV. The regeneration reaction is a combination of the KN amplitudes (with I = 0 and 1) and the amplitude (I = 1) and is very sensitive to the various KN phase-shift solutions, some of which show an exotic I = 0, P1 resonance. Our results have been expressed in terms of frequency distributions and cross sections, normalised by the Λ0π+ reaction. These results have been compared with the predictions of various partial-wave analyses. Qualitatively we can eliminate the P1 non-resonant solution, though no solution correctly predicts our results. 相似文献
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Frédérin abwergel Jacques Herbert Ballly Herbert Ballly H Beirao da Veiga VA Solonnikov 《偏微分方程通讯》2013,38(9-10):1323-1358
We study a class of stationary transport equation with nonlocal low-order tems We obtain the existence and uniqueness of a solution in sobolev spaces 相似文献
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非线性涡黏性系数模型和代数应力模型联系了线性涡黏性系数湍流模型和完整的微分
雷诺应力模型.随着它们受到日益关注,其形式也越来越多样化.本篇综述的目的是对这些模
型加以总结并比较它们之间的共同点及不同之处,指出它们与完整微分雷诺应力模型之间的
关系,以及相对于线性涡黏性系数模型而言它们在预报流场上所具有的优势. 相似文献
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M.J. Corden J.D. Dowell J. Garvey M. Jobes I.R. Kenyon J. Mawson T. McMahon I.F. Corbett R.J. Esterling N.H. Lipman P.J. Litchfield K.C.T.O. Sumorok G. Alexander S. Dagan Y. Gnat E.H. Bellamy M.G. Green N. Harnew D.H. Thomas 《Nuclear Physics B》1978,136(1):77-94
Data on the charge-exchange reaction π?p → (π+π?π0)n have been taken at beam momenta of 12 and 15 GeV/c, using the CERN Omega Multiparticle Spectrometer. A partial-wave analysis has been made of the (3π)0 system. We observe both natural and unnatural spin-parity production. The natural parity states can be identified with established resonances. In addition a natural spin-parity enhancement is observed at a mass of about 2 GeV/c2 with JP = 4+ preferred. We have called this effect the A21 (2030). The unnatural spin-parity production found is consistent with reggeized Deck model predictions. No unambiguous A1 or A3 production is observed. 相似文献
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M.J. Corden J.D. Dowell J. Garvey M. Jobes I.R. Kenyon J. Mawson T. McMahon I.F. Corbett R.J. Esterling N.H. Lipman P.J. Litchfield K.C.T.O. Sumorok G. Alexander S. Dagan Y. Gnat E.H. Bellamy M.G. Green N. Harnew D.H. Thomas 《Nuclear Physics B》1978,138(2):235-252
Data on the reaction π?p → π+π?π0 have been taken at 12 and 15 GeV/c with the CERN Omega multiparticle spectrometer. In a 3-pion partial-wave analysis strong production of is observed. Total and differential cross sections are determined and density matrix elements presented as a function of t in the t- and s-channel frames. The energy dependence of A20 production is studied, and a comparison of production is made. 相似文献