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31.
Beate Heinemann 《Pramana》2000,55(1-2):63-72
Highlights are presented of the latest measurements from the H1, ZEUS and HERMES experiments at HERA. 相似文献
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Prakash R Czaja AU Heinemann FW Sellmann D 《Journal of the American Chemical Society》2005,127(40):13758-13759
The new ruthenium compound [Ru(NO)(pysiS4)]Br (3) (pysiS4 = 2,6-bis(3-triphenylsilyl-2-sulfanylphenylthiomethyl)pyridine), containing sterically bulky SiPh3 groups ortho to the thiolate donors, has been synthesized. In solution, 3 releases NO efficiently on exposure to visible light (lambda >/= 455 nm) at room temperature to afford [Ru(Br)(pysiS4)] (4). Treatment of 4 with NO yielded exclusively 3 without any metal-bound side reaction. 相似文献
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Türkoglu G Heinemann FW Burzlaff N 《Dalton transactions (Cambridge, England : 2003)》2011,40(17):4678-4686
The new N,N,O ligand 2,2-bis(3,5-dimethylpyrazol-1-yl)propionic acid (2,2-Hbdmpzp) (2) and its transition metal complexes [Mn(2,2-bdmpzp)(CO)(3)] (3), [Re(2,2-bdmpzp)(CO)(3)] (4), [Cu(2,2-bdmpzp)(2)] (5), and [Ru(2,2-bdmpzp)Cl(L)(PPh(3))] [L = PPh(3) (6), N(2) (7), CO (8a/b), SO(2) (9a/b)] have been synthesized, characterized and compared to analogous complexes bearing a bis(3,5-dimethylpyrazol-1-yl)acetic acid. It was found that the additional methyl group has a remarkable influence on the stability and reactivity of transition metal complexes. 相似文献
36.
Meier R Maigut J Kallies B Lehnert N Paulat F Heinemann FW Zahn G Feth MP Krautscheid H van Eldik R 《Chemical communications (Cambridge, England)》2007,(38):3960-3962
The equilibrium between the twist-boat (tb) and half-chair (hc) conformers of the central diamine chelate ring of [Fe(III)(tmdta)]- in solids and aqueous solution has been studied by Raman spectroscopy, supported by calculated Raman spectra using Density Functional Theory. 相似文献
37.
Immo Weber Frank W. Heinemann Panagiotis Bakatselos Ulrich Zenneck 《Helvetica chimica acta》2007,90(4):834-845
A pressure‐controlled procedure for the SN1 reaction of rac‐1‐[(dimethylamino)methyl]‐2‐(tributylstannyl)ferrocene ( 1 ) to rac‐1‐(phthalimidomethyl)‐2‐(tributylstannyl)ferrocene ( 2 ) was developed. Pd0‐Catalyzed Stille coupling of 2 with iodobenzene afforded rac‐1‐phenyl‐2‐(N‐phthalimidomethyl)ferrocene ( 5 ) in 74% yield; after trace enrichment by crystallization of the combined mother liquors, one single crystal of each, 5 , catalysis intermediate trans‐iodo(σ‐phenyl)bis(triphenylarsino)palladium(II) ( 7 ), trans‐diiodobis(triphenylarsino)palladium(II) ( 8 ), and rac‐2,2′‐bis(phthalimidomethyl)‐1,1′‐biferrocene ( 9 ) could be isolated by crystal sorting under a microscope and characterized by X‐ray crystal structure analysis. Furthermore, 5 was deprotected to amine ( 11 ), which does even survive the Birch reduction to rac‐1‐(aminomethyl)‐2‐(cyclohexa‐2,5‐dienyl)ferrocene ( 12 ). 相似文献
38.
The sodium benzophenone ketyl-induced reaction of [Ru3(CO)12] with bis(diphenylphosphanyl)amine Ph2PN(H)PPh2 (dppa) in THF resulted in the formation of the expected metal cluster [Ru3(CO)10(μ-dppa)] ( 1 ) in high yield. 1 was fully characterized by spectroscopic means and crystals of the compound suitable for X-ray diffraction were obtained from dichloromethane/dioxane. The molecular structure of 1 as its dioxane solvate was determined by X-ray crystallography. The compound crystallized in a new crystal structure of [Ru3(CO)10(μ-dppa)] in the triclinic space group P1 , whereas that compound was described in an earlier report crystallizing from chloroform in the monoclinic space group P21/c. 相似文献
39.
Ahmad Fahim Habib Thomas Heinemann Grace G. Manahan Daniel Ullmann Paul Scherkl Alexander Knetsch Andrew Sutherland Andrew Beaton David Campbell Lorne Rutherford Lewis Boulton Alastair Nutter Adam Hewitt Alexander Dickson Oliver S. Karger Michael D. Litos Brendon D. O'Shea Gerard Andonian David L. Bruhwiler Georg Pretzler Thomas Wilson Zhengming Sheng Michael Stumpf Lars Reichwein Alexander Pukhov John R. Cary Mark J. Hogan Vitaly Yakimenko James B. Rosenzweig Bernhard Hidding 《Annalen der Physik》2023,535(10):2200655
Plasma wakefield accelerators offer accelerating and focusing electric fields three to four orders of magnitude larger than state-of-the-art radiofrequency cavity-based accelerators. Plasma photocathodes can release ultracold electron populations within such plasma waves and thus open a path toward tunable production of well-defined, compact electron beams with normalized emittance and brightness many orders of magnitude better than state-of-the-art. Such beams will have far-reaching impact for applications such as light sources, but also open up new vistas on high energy and high field physics. This paper reviews the innovation of plasma photocathodes, and reports on the experimental progress, challenges, and future prospects of the approach. Details of the proof-of-concept demonstration of a plasma photocathode in 90° geometry at SLAC FACET within the E-210: Trojan Horse program are described. Using this experience, alongside theoretical and simulation-supported advances, an outlook is given on future realizations of plasma photocathodes such as the upcoming E-310: Trojan Horse-II program at FACET-II with prospects toward excellent witness beam parameter quality, tunability, and stability. Future installations of plasma photocathodes also at compact, hybrid plasma wakefield accelerators, will then boost capacities and open up novel capabilities for experiments at the forefront of interaction of high brightness electron and photon beams. 相似文献
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