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761.
762.
763.
Marcel Gielen Jacqueline Meunier-Piret Monique Biesemans Rudolph Willem Abdelaziz El Khloufi 《应用有机金属化学》1992,6(1):59-67
Di-n-butyltin(IV) and diethyltin(IV) 2,3,4-, 2,4,5- and 3,4,5-trimethoxybenzoates [(CH3O)3C6H2COO]2SnR [Type a] and {[(CH3O)3C6H2COO]R2Sn}2O [Type b] have been synthesized and characterized spectroscopically. The crystal structure of bis[di-n-butyl(3,4,5- trimethoxybenzoato)tin] oxide has been determined. The triclinic unit cell contains one centrosymmetric dimer; a = 15.919(2) Å, b = 11.711(3) Å, c = 13.475(1) Å, and α = 63.63(2)°, β = 67.49(1)°, γ = 76.61(2)°. The geometry of the dimer is very similar to that of bis[di-n-butyl(5-methoxysalicylatotin] oxide), with two different types of five-coordinate tin atoms and one central planar Sn2O2 ring. 相似文献
764.
Application of an improved method for measurements of gaseous nitric acid in the nonurban atmosphere
Summary A modified filter technique to separate particles and gaseous HNO3 is described, which is based on the use of filters of the Millipore FPLG type in combination with a virtual impactor. It enables routine measurements of gaseous HNO3 in the atmosphere at background levels. Some results of measurements both in the marine background and over rural and semi-rural continental regions are presented. 相似文献
765.
A. Jungclaus K. P. Lieb C. J. Gross J. Heese D. Rudolph D. J. Blumenthal P. Chowdhury P. J. Ennis C. J. Lister Ch. Winter J. Eberth S. Skoda M. A. Bentley W. Gelletly B. J. Varley 《Zeitschrift für Physik A Hadrons and Nuclei》1991,340(2):125-139
High spin states in the transitional nucleus87Nb up to 14 MeV excitation have been established for the first time via the reactions40Ca(50Cr, 3p)87Nb and58Ni (32S, 3p)87Nb. The87Nbγ-radiations have been identified throughγ-ray spectra taken in coincidence with the evaporation residues detected in the Daresbury recoil separator or with multiple proton emission. Gamma-gamma coincidences, DCO ratios,γ-ray angular distributions and lifetimes have been measured. A total of some 100 transitions have been placed into a level scheme comprising of sixty states. The one-quasiparticle (1qp) bands of either parity and several other band-like structures have been identified, some containing alignedg 9/2 nucleons. Moderately enhancedE2 in-band transitions of 13–48 W.u. as well as several weakE2 yrast transitions connecting bands with different quasiparticle numbers have been found. Similarities with respect to theN=46 isotones83Rb,84Sr,85Y,86Zr and88Mo are discussed. 相似文献
766.
We report the first experimental demonstration of a quantum controlled-NOT gate for different photons, which is classically feed forwardable. In the experiment, we achieved this goal with only the use of linear optics, an entangled ancillary pair of photons, and postselection. The techniques developed in our experiment are of significant importance for quantum information processing with linear optics. 相似文献
767.
Resource-efficient linear optical quantum computation 总被引:1,自引:0,他引:1
We introduce a scheme for linear optics quantum computation, that makes no use of teleported gates, and requires stable interferometry over only the coherence length of the photons. We achieve a much greater degree of efficiency and a simpler implementation than previous proposals. We follow the "cluster state" measurement based quantum computational approach, and show how cluster states may be efficiently generated from pairs of maximally polarization entangled photons using linear optical elements. We demonstrate the universality and usefulness of generic parity measurements, as well as introducing the use of redundant encoding of qubits to enable utilization of destructive measurements--both features of use in a more general context. 相似文献
768.
Propargyl-alkyl biradical 12 generated by photodecarbonylation of title ketone 3 undergoes ring closure to cyclobutane 7 and to vinyl carbene 13 , this latter intermediate rearranging to the 5-ethylidenecyclopentenes 8a and 8b . 相似文献
769.
I.?RagnarssonEmail author C.?Andreoiu T.?D?ssing C.?Fahlander D.?Rudolph S.??berg 《The European Physical Journal A - Hadrons and Nuclei》2003,20(1):35-36
Exact and approximate quantum numbers of the cranked Nilsson-Strutinsky (CNS) formalism are exploited to calculate excited bands in fixed configurations with the energy of the individual bands minimized with respect to deformation for all spin values. The formalism is applied to 59Cu, where all bands which appear important in the decay out of the superdeformed band are calculated.Received: 14 November 2002, Published online: 17 February 2004PACS:
21.10.Ma Level density - 21.60.Cs Shell model - 23.20.Lv
transitions and level energies - 27.50. + e
C. Andreoiu: Present address: Department of Physics, University of Guelph, Guelph, Ontario, Canada N1G 2W1. 相似文献
770.
We show that the sender and the receiver each require coherent devices in order to achieve unconditional continuous variable quantum teleportation (CVQT), and this requirement cannot be achieved with conventional laser sources, linear optics, ideal photon detectors, and perfect Fock state sources. The appearance of successful CVQT in recent experiments is due to interpreting the measurement record fallaciously in terms of one preferred ensemble (or decomposition) of the correct density matrix describing the state. Our analysis is unrelated to technical problems such as laser phase drift or finite squeezing bandwidth. 相似文献