The paper deals with the use of an alllylphosphinite ligand for the synthesis of a new family of metallacycles, the iridaoxalaphosphalanes through nucleophilic attack of phosphanes to the allyl ...moiety of the ligand.
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An alkenylphosphinite compound has been used to synthesize the unknown iridaoxaphospholane complexes which have been characterized in solution and solid state. The reactions took place in mild conditions and the product were obtained in good yields. The synthesis of the iridaoxaphospholane complexes is based on the capability of the alkenylphosphinite compound to behave as a κ1P or κ3(P, C, C) ligand when bonded to a metal complex. Theoretical calculations have been performed to explain the formation of the iridaoxaphospholane derivative due to a lower energy barrier for the nucleophilic attack at the terminal carbon of the olefin.
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•Synthesis of optically active half-sandwich chloro, diphosphinite, germyl ruthenium complexes.•X-ray crystal structure of Ru(GeCl3)(η5-C5Me5)L ...(L = (R,R)-(+)-1,2-bis(diphenyl)phosphanyloxy-1,2-diphenylethane).•Synthesis of the first bimetallic compounds Ru-GeR3 (R = H, Me) with a chiral phosphinite bidentate ligand.
Reaction of RuCl(η5-C5Me5)L and RuCl(η5-C9H7)L (L = 1,2-bis(diphenyl) phosphanyloxy-1,2-diphenylethane) with an excess of GeCl2·dioxane afforded the half-sandwich trichlorogermyl complexes Ru(GeCl3)(η5-C5Me5)L (1a) and Ru(GeCl3)(η5-C9H7)L (1b). Trihydridogermyl derivatives Ru(GeH3)(Cp′)L Cp′ = η5-C5Me5 (2a), η5-C9H7 (2b) were obtained by treating 1a and 1b with LiAlH4. Reaction of compound 1a with MeMgBr gave the monomethyl derivative Ru(GeMeCl2)(η5-C5Me5)L (3a) while the reaction between the complex 1b and MeMgBr yielded the trimethylgermyl derivative Ru(GeMe3)(η5-C9H7)L (3b). All the complexes present optical activity. The complexes were characterized spectroscopically and the X-ray crystal structure of Ru(GeCl3)(η5-C5Me5)L (1a) was determined.
(ProQuest: ... denotes formulae and/or non-USASCII text omitted; see image) Abstract The production cross-sections of B mesons are measured in pp collisions at a centre-of-mass energy of 7 TeV, using ...data collected with the LHCb detector corresponding to a integrated luminosity of 0.36 fb^sup -1^. The B ^sup +^, B ^sup 0^ and ... mesons are reconstructed in the exclusive decays B ^sup +^ arrow right J/psiK ^sup +^, B ^sup 0^ arrow right J/psiK ^sup *0^ and ..., with J/psi arrow right mu ^sup +^ mu ^sup -^, K ^sup *0^ arrow right K ^sup +^pi^sup -^ and arrow right K ^sup +^ K ^sup -^. The differential cross-sections are measured as functions of B meson transverse momentum p ^sub T^ and rapidity y, in the range 0 < p ^sub T^ < 40 GeV/c and 2.0 < y < 4.5. The integrated cross-sections in the same p ^sub T^ and y ranges, including charge-conjugate states, are measured to be ...where the third uncertainty arises from the pre-existing branching fraction measurements. Figure not available: see fulltext.
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•Preparation of half-sandwich ruthenium allenylidene complexes.•Preparation of diazoalkane complexes of ruthenium.•The diazoalkane unit presents an important bending angle RuNN.•The ...metal-ligand overlap in the HOMO plays a role in the bending of the RuNN angle.•DFT studies corroborate the role of metal–ligand overlap in the HOMO and lower occupied orbitals to the acute character of the RuNN angle.
Half-sandwich mixed phosphine-phosphinite ruthenium complexes RuCp’Cl(PPh3)L Cp’ = Cp (1), Cp* (2), and RuCp*ClL2 (3) were prepared by substitution of the triphenylphosphine by the phosphinite ligand PPh2OCH2Ph, L, on the parent complexes RuCp’Cl(PPh3)2. Allenylidene compounds Ru(η5-C5H5){CC = CPh2}(PPh3)LPF6 (4) and Ru(η5-C5Me5){CC = CPhR}(L)(L’)BPh4 L’ = PPh3(5), L (6); R = Ph (a), R = Me (b) were obtained by reaction of compounds 1–3 with the appropriate propargylic alcohols 1,1-diphenyl-2-propyn-1-ol, and 2-phenyl-3-butyn-2-ol. Diazoalkane complexes RuCp(N2CAr1Ar2)(PPh3)LPF6 Ar1 = Ar2 = Ph (7a), Ar1Ar2 = C12H8 (7b) and RuCp*{N2C(C12H8)}L2PF6 (8) were obtained by reaction of 1 or 3 with the corresponding diazoalkanes in the presence of NaPF6. Complexes were characterized by IR and NMR spectroscopy and, in the case of compounds 1 and 7a, by X-ray diffraction analysis.
LHCb Silicon Tracker DAQ and ECS Online Systems Esperante, Daniel; Rodriguez, P; Buchler, A ...
IEEE transactions on nuclear science,
2010-April, 2010-04-00, 20100401, Letnik:
57, Številka:
2
Journal Article
Recenzirano
The LHCb experiment at CERN is designed to perform precision measurements of b quark decays. The Silicon Tracker plays a crucial role in reconstructing particle trajectories and consists of two ...silicon micro-strip detectors, the Tracker Turicensis and the Inner Tracker. The radiation environment and the magnetic field represent new challenges for the implementation of the Experiment Control System (ECS) and the data acquisition (DAQ). The DAQ has to deal with ~272 000 analog read-out channels and real-time DAQ at a rate of ~ 1.1 MHz with data processing at the Trigger Electronics and L1 (TELL1) board level. The TELL1 real-time algorithms for clustering thresholds and other computations run on dedicated FPGAs. After data processing the total throughput amounts to about 6.4 GB from an input data rate of ~ 337 GB per second. The ECS is based on the hierarchical finite state machine paradigm and allows distributed control access and multi-platform use. The ECS is able to control and monitor the detector hardware infrastructure (power supplies, DAQ electronics ...) as well as monitor the environmental parameters. It can also take automated actions on warnings or alarms. Finally a completely independent, hardware based safety system ensures the detector safe operation.
Trichlorostannyl complexes Ru(SnCl3) (Cp')L (2a-c) were prepared by treatment of optically active half-sandwich chlorocomplexes RuCl(Cp')L (1a-c) with an excess of SnCl2.2H2O in ethanol. Treatment of ...trichlorostannyl complexes 2a-c with NaBH4 afforded trihydridostannyl derivatives Ru(SnH3) (Cp')L (3a-c) in moderated yields. Treatment of 2a-c with MgBrMe gave the trimethylstannyl complexes Ru(SnMe3) (Cp')L (4a-c). Alkynylstannyl derivatives Ru{Sn(C≡CPh)3}(Cp')L (5a-c) were prepared by treatment of trichlorostannyl compounds 2a-c with an excess of LiC≡CPh in thf. All the complexes present optical activity. The complexes were characterized spectroscopically and by X-ray crystal structure determination of RuCl(η5-C5Me5)L (1b), Ru(SnCl3) (η5-C5Me5)L (2b), and Ru(SnCl3) (η5-C9H7)L (2c). The influence of different ligands on the RuP interaction in several complexes 1a-c, 2a-c and 3a-c was evaluated by DFT calculations. These calculations indicate that SnCl3- has a stronger stabilization effect than Cl- and the same occurs between C9H7 and C5Me5. These relative stabilities combined with the distortion energies of the fragments produce a stabilizing effect in the RuP bonds of complex 2c that is twice as strong as in the 1b complex.
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•Synthesis of optically active half-sandwich chloro, diphosphinite, stannyl ruthenium complexes.•Calculated NPA charges indicate high polarization of the Ru-P bonds.•X-ray crystal structure of RuCl(η5-C5Me5)L, Ru(SnCl3)(η5-C5Me5)L and Ru(SnCl3)(η5-C9H7)L (L= (R,R)-(+)-1,2-bis(diphenyl)phosphanyloxy-1,2-diphenylethane).
(ProQuest: ... denotes formulae and/or non-USASCII text omitted; see image) Abstract A measurement of the inclusive Z arrow right ττ cross-section in pp collisions at ... is presented based on a ...dataset of 1.0 fb^sup -1^ collected by the LHCb detector. Candidates for Z arrow right tau tau decays are identified through reconstructed final states with two muons, a muon and an electron, a muon and a hadron, or an electron and a hadron. The production cross-section for Z bosons, with invariant mass between 60 and 120 GeV/c ^sup 2^, which decay to tau leptons with transverse momenta greater than 20 GeV/c and pseudorapidities between 2.0 and 4.5, is measured to be sigma^sub pparrow rightZarrow rightττ^ = 71.4 ± 3.5 ± 2.8 ± 2.5 pb; the first uncertainty is statistical, the second is systematic, and the third is due to the uncertainty on the integrated luminosity. The ratio of the cross-sections for Z arrow right tau tau to Z arrow right mumu is determined to be 0.93 ± 0.09, where the uncertainty is the combination of statistical, systematic, and luminosity uncertainties of the two measurements.Figure not available: see fulltext.
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