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1.
[reaction: see text] The gas-phase thermal isomerization of cis,anti,cis-tricyclo[6.3.0.0(2,7)]undec-3-ene (1) to endo-tricyclo[5.2.2.0(2,6)]undec-8-ene (2) at 315 degrees C occurs cleanly through a symmetry-forbidden [1,3] suprafacial,retention (sr) pathway. 相似文献
2.
3.
Metal/superconductor/semiconductor (Ag/Hg-1212/CdSe) hetero-nanostructures have been fabricated using pulse-electrodeposition
technique and are characterized by X-ray diffraction (XRD), full-width at half-maximum (FWHM) and scanning electron microscopy
(SEM) studies. The junction capacitance of Ag/Hg-1212, Hg-1212/CdSe and Ag/Hg-1212/CdSe heterojunctions is measured in dark
and under laser irradiation at room temperature. The nature of the junction formed and built-in-junction potentials were determined.
The increase in carrier concentration across the junction due to photo-irradiation has been observed. 相似文献
4.
One of the innovative technological directions for the high-temperature superconductors has been persued by fabricating the
heteroepitaxial multilayer structures such as superconductor-semiconductor heterostructures. In the present investigation,
metal/superconductor/semiconductor (Ag/Tl-2223/CdSe) hetero-nanostructures have successfully been fabricated using dc electrodeposition
technique and were characterized by X-ray diffraction (XRD), full-width at half-maximum (FWHM) and scanning electron microscopy
(SEM) studies. The measurement of junction capacitance as a function of biasing voltage was used for the estimation of junction
built-in-potential (V
D) and to study the charge distribution in a heterojunction. The Mott-Schottky plots were measured for each junction in dark
and under the photo-irradiation. The effect of laser irradiation on C-V characteristics of hetero-nanostructure has been studied. 相似文献
5.
J.M. Nitschke M. Fowler A. Ghiorso R.E. Leber M.E. Leino M.J. Nurmia L.P. Somerville K.E. Williams E.K. Hulet J.H. Landrum R.W. Lougheed J.F. Wild C.E. Bemis R.J. Silva P. Eskola 《Nuclear Physics A》1981,352(1):138-146
A rotating drum system was used to search for an 80 ms spontaneous fission (sf) activity in the reaction of 15N with 249Bk. No such activity was found beyond a cross section limit of 0.5 nb. A sf activity with a half-life of 23 ± 2 ms and a maximum formation cross section of 19 ± 4 nb at 82 MeV was observed. The identity of this activity has not been determined. 相似文献
6.
James F. Woodward André de Klerk Gail Kahler Kathrine Leber Peter Pompei Daniel Schultz Sharon Stern 《Foundations of Physics》1972,2(2-3):241-244
An experiment designed to test the highly speculative hypothesis of photon consciousness was executed. It was found that, within the accuracy attainable with the apparatus, there is no empirical justification for the hypothesis. 相似文献
7.
S. S. Barshay R. E. Leber R. M. Lambrecht 《Applied Physics A: Materials Science & Processing》1974,5(1):67-70
The Doppler broadening of positron annihilation photons was measured in 17 metals. A model which considers the positron lifetime spectra in metals to be composed of terms for annihilation with conduction and core electrons and surface centers of low electron momentum is used to correlate calculated core annihilation rates with the Doppler lineshape. Ta metal was doped with defects with high energy implantations of14N+4 ions at variable doses. Differences in the Doppler linewidths were ascribed as being principally a reflection of the probabilty of annihilation with core electrons relative to annihilation with conduction electrons. 相似文献
8.
J.M. Weber E. Leber M.-W. Ruf H. Hotop 《The European Physical Journal D - Atomic, Molecular, Optical and Plasma Physics》1999,7(4):587-594
Using a high resolution laser photoelectron attachment method, we have studied the formation of (H
2
O)
q
- (q = 2, 6, 7, 11, 15) cluster ions in collisions of slow free electrons (E = 1-80 meV) and Rydberg electrons (n = 12-300) with water clusters. Resonances at zero energy have been observed, the shapes of which are strongly dependent on
cluster size. The results are discussed in terms of the formation of metastable negative ions.
Received 8 March 1999 相似文献
9.
G. D. Barr P. Buchholz D. Cundy N. Doble L. Gatignon P. Grafström R. Hagelberg H. Wahl K. J. Peach T. Beier H. Blümer D. Coward R. Heinz K. Kleinknecht F. Leber P. Mayer B. Renk H. Rohrer H. G. Sander J. Scheidt J. Staeck A. Wagner E. Augé D. Fournier L. Iconomidou-Fayard O. Perdereau A. C. Schaffer L. Serin L. Bertanza P. Calafiura M. Calvetti R. Carosi R. Casali C. Cerri I. Mannelli V. M. Marzulli A. Nappi G. M. Pierazzini M. Holder A. Kreutz M. Rost R. Werthenbach 《Zeitschrift fur Physik C Particles and Fields》1995,65(3):361-365
Data from the NA31 experiment at CERN have been used to measure the branching ratio of the double Dalitz decay of the long-lived neutral kaon. Eight events have been found with negligible background. The measured distribution of the angle between the planes of the two e+e?-pairs favours aCP=?1 state for the long-lived neutral kaon. 相似文献
10.
N. A. Wogman L. J. Bond A. E. Waltar R. E. Leber 《Journal of Radioanalytical and Nuclear Chemistry》2005,263(1):137-143
Summary The U.S. Department of Energy supports 24 fellowships for students to attend six-week programs at either San Jose State University in California, or Brookhaven National Laboratory (BNL) in New York. The American Chemical Society through the Division of Nuclear Science and Technology operates both schools. The twelve students at the BNL program are enrolled in the State University of New York at Stony Brook (SUNYSB) and receive 3 college credits for the lecture course (CHE-361) and 3 additional credits for the laboratory course (CHE-362). In addition to lectures and laboratories, students tour various nuclear facilities offsite, at BNL, and at SUNYSB. Opportunities are given the students to interact with faculty and scientists within the profession through the Guest Lecture Program. Further details are discussed along with results of student surveys for the years 1999 through 2002. 相似文献