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1.
M. Ferro-Luzzi Z.-L. Zhou J.F.J. van den Brand H.J. Bulten J. Lang H.R. Poolman 《Hyperfine Interactions》1997,110(3-4):239-257
We present data showing hyperfine transitions in an atomic deuterium beam induced by the (476 MHz) radio-frequency field of
a 704 MeV electron beam in a storage ring. A polarized deuterium beam, produced in an atomic beam source, was crossed with
a stored electron beam and analyzed with a Breit--Rabi polarimeter. Electron-beam induced transitions were singled out by
injecting different combinations of hyperfine states. Transition probabilities as high as 70% were measured at large currents
(~ 100 mA). All possible deuterium transitions for a radio-frequency of 476 MHz were observed. In addition, a 1--6 transition
resulting from the first harmonic (952 MHz) was observed.
The effects of these transitions are of general importance for the polarized internal target technique applied in nuclear
and particle physics experiments. The data are reasonably described by numerical estimates. The observed mechanism can be
exploited to create nuclear polarized atoms when injecting electron polarized atoms with no net nuclear polarization into
a storage cell. However, when nuclear polarized atoms are injected, care should be taken to avoid this mechanism, since it
would result in depolarization of the atoms. The studies enabled us to choose the magnetic guide field during our spin-dependent
electron--deuteron scattering experiments, such that electron-beam induced depolarizing effects were avoided.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
2.
van den Brand JF Ent R Anthony PL Arnold RG Arrington J Beise EJ Belz JE Bosted PE Bulten H Chapman MS Coulter KP Dietrich FS Epstein M Filippone BW Gao H Gearhart RA Geesaman DF Hansen J Holt RJ Jackson HE Jones CE Keppel CE Kinney ER Kuhn S Lee K Lorenzon W Lung A Makins NC Margaziotis DJ McKeown RD Milner RG Mueller B Napolitano J Nelson J O'Neill TG Papavassiliou V Petratos GG Potterveld DH Rock SE Spengos M Szalata ZM Tao LH van Bibber K Wasson DA White JL Zeidman B 《Physical review D: Particles and fields》1995,52(9):4868-4871
3.
Makins NC Ent R Chapman MS Hansen J Lee K Milner RG Nelson J Arnold RG Bosted PE Keppel CE Lung A Rock SE Spengos M Szalata ZM Tao LH White JL Coulter KP Geesaman DF Holt RJ Jackson HE Papavassiliou V Potterveld DH Zeidman B Arrington J Beise EJ Belz E Filippone BW Gao H Lorenzon W Mueller B McKeown RD O'Neill TG Epstein M Margaziotis DJ Napolitano J Kinney E Anthony PL van Bibber K Dietrich FS Gearhart RA Patratos GG Kuhn SE van den Brand JF Bulten H Jones CE 《Physical review letters》1994,72(13):1986-1989
4.
The crystal and molecular structure of cyclopentadienyltin(II) chloride has been determined from three-dimensional X-ray data. The crystals are orthorhombic, space group Pc21n. The unit cell, of dimensions a = 5.711(5), b = 6.225(5), c = 17.24(2) Å, contains four molecules. The structure has been refined by full matrix least squares techniques to a final R value of 0.083 for 717 independent reflections. In the crystal unsymmetrical tin-chlorine bridges are present between the units of C5H5SnCl.It is suggested that in cyclopentadienyltin(II) compounds the cyclopentadienyl group occupies more than one coordination site as a result of the donation of π electron density from the cyclopentadienyl ring into an empty acceptor orbital of the tin atom having π symmetry. 相似文献
5.
Klaas D. Bos Eric J. Bulten Harry A. Meinema Jan G. Noltes 《Journal of organometallic chemistry》1979,168(2):159-162
Reaction of dicyclopentadienyltin(II) with pentamethylantimony gives [Me4Sb]2+[(C5H5)4Sn]2?, the first example of an anionic organotin(II) species. 相似文献
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Bulten HJ Anthony PL Arnold RG Arrington J Beise EJ Belz E van Bibber K Bosted PE van den Brand JF Chapman MS Coulter KP Dietrich FS Ent R Epstein M Filippone BW Gao H Gearhart RA Geesaman DF Hansen J Holt RJ Jackson HE Jones CE Keppel CE Kinney E Kuhn SE Lee K Lorenzon W Lung A Makins NC Margaziotis DJ McKeown RD Milner RG Mueller B Napolitano J Nelson J O'Neill TG Papavassiliou V Petratos GG Potterveld DH Rock SE Spengos M Szalata ZM Tao LH White JL Zeidman B 《Physical review letters》1995,74(24):4775-4778
9.
ω-Haloalkyltin trihalides, X(CH2)nSnX3 (n ≧ 3; X = halogen) can readily be prepared in high yields by the direct reaction of stannous halides with α,ω-dihaloalkanes, catalysed by trialkylantimony compounds. The compounds are versatile starting materials for the synthesis of a variety of ω-functionallysubstituted organotin compounds R3-mXmSn(CH2)n Y (R = alkyl, phenyl; m = 0-3; X = Cl, Br, O; Y = Br, NMe2, NEt2, COOH, CHOHR, R3Sn). 1H-NMR spectral data for a series of such compounds are presented. The trends observed in the chemical shifts and the 119Sn—methyl proton coupling constants of Me3-m BrmSn(CH2)nBr (m = 0-3; n = 3-5) are discussed in terms of inductive effects. Intramolecular coordination between the ω-bromine atom and tin could not be demonstrated. 相似文献
10.
Studies of the reaction of tin dichloride and of metallic tin with hydrochloric acid gas in diethyl ether are described. On the basis of spectroscopic and analytical data it is concluded that the product is not to be regarded as a tin-hydrogen bonded analog of chloroform, viz. trichlorostannane(IV), and the formation of an equilibrium mixture of hydrogen trichlorostannate(II) and dihydrogen tetrachlorostannate(II) is tentatively suggested. The complexes slowly decompose as a result of diethyl ether cleavage, yielding ethanol and ethyl chloride, together with traces of ethyltin trichloride.The mechanism of addition of the complexes to methyl acrylate is discussed in terms of a 1,4-addition involving initial protonation of oxygen. Reaction of the resulting β-carbomethoxyethyltin trichloride with tin or with zinc gives rise to mixtures of bis(β-carbomethoxyethyl)tin dichloride and tris(β-carbomethoxyethyl)tin chloride Similar reactions were observed for the first time with methyltin trichloride, the reaction with zinc being extremely fast at room temperature. 相似文献