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71.
72.
IR+UV double resonant ion-dip and ion-enhancement spectroscopies are employed to study the nu3 asymmetric CH stretch vibration fundamental of CH3 in the ground and 3p(z) Rydberg electronic states. CH3 radical is synthesized in the supersonic jet expansion by flash pyrolysis of azomethane (CH3NNCH3) prior to the expansion. The Q band of the 3(1) (1) 3p(z)<--X transition of CH3, not detected by conventional UV resonantly enhanced multiphoton ionization (REMPI) spectroscopy, is determined to lie at 59,898 cm(-1) using IR+UV REMPI spectroscopy. Energy of the asymmetric CH stretch of CH3 in the 3p(z) Rydberg state, nu3(3p(z)), is 3087 cm(-1), redshifted by approximately 74 cm(-1) with respect to ground state nu3(X). 相似文献
73.
Leon Bernstein 《Archiv der Mathematik》1964,15(1):421-429
Ohne Zusammenfassung
Helmut Hasse zu seinem 65. Geburtstage 相似文献
74.
D. Bernstein 《Fresenius' Journal of Analytical Chemistry》1961,182(5):321-323
Zusammenfassung Zur quantitativen Bestimmung einer Lithiumphenyllösung wird eine bestimmte Menge Lösung mit überschüssiger Jodlösung umgesetzt. Dabei bildet sich quantitativ Jodbenzol. Im Gaschromatographen erfolgt anschlie\end die Bestimmung der Konzentration an Jodbenzol. Daraus kann die Konzentration der eingesetzten Lithiumphenyllösung ermittelt werden. Andere lithiumorganische Verbindungen stören dabei nicht. Die Genauigkeit der Methode betrÄgt bei der verwendeten Apparatur 2%. 相似文献
75.
76.
Jeffrey A. Bean Badri Tiwari Gergo Szakmány Gary H. Bernstein P. Fay Wolfgang Porod 《Infrared Physics & Technology》2010,53(3):182-185
This work focuses on the fabrication and response of dipole antenna-coupled metal–oxide–metal diode detectors to long-wave infrared radiation. The detectors are fabricated using a single electron beam lithography step and a shadow evaporation technique. The detector’s characteristics are presented, which include response as a function of incident infrared power and polarization angle. In addition, the effect of dipole antenna length on detection characteristics for 10.6 μm radiation has been measured to determine resonant lengths. The response of the detector shows a first resonance at a dipole length of 3.1 μm, a second resonance at 9.3 μm, and third at 15.5 μm. The zeros intermediate to the resonances are also evident. 相似文献
77.
This study tested the relationship between frequency selectivity and the minimum spacing between harmonics necessary for accurate fo discrimination. Fundamental frequency difference limens (fo DLs) were measured for ten listeners with moderate sensorineural hearing loss (SNHL) and three normal-hearing listeners for sine- and random-phase harmonic complexes, bandpass filtered between 1500 and 3500 Hz, with fo's ranging from 75 to 500 Hz (or higher). All listeners showed a transition between small (good) fo DLs at high fo's and large (poor) fo DLs at low fo's, although the fo at which this transition occurred (fo,tr) varied across listeners. Three measures thought to reflect frequency selectivity were significantly correlated to both the fo,tr and the minimum fo DL achieved at high fo's: (1) the maximum fo for which fo DLs were phase dependent, (2) the maximum modulation frequency for which amplitude modulation and quasi-frequency modulation were discriminable, and (3) the equivalent rectangular bandwidth of the auditory filter, estimated using the notched-noise method. These results provide evidence of a relationship between fo discrimination performance and frequency selectivity in listeners with SNHL, supporting "spectral" and "spectro-temporal" theories of pitch perception that rely on sharp tuning in the auditory periphery to accurately extract fo information. 相似文献
78.
Michael DG Adamson P Alexopoulos T Allison WW Alner GJ Anderson K Andreopoulos C Andrews M Andrews R Arms KE Armstrong R Arroyo C Auty DJ Avvakumov S Ayres DS Baller B Barish B Barker MA Barnes PD Barr G Barrett WL Beall E Becker BR Belias A Bergfeld T Bernstein RH Bhattacharya D Bishai M Blake A Bocean V Bock B Bock GJ Boehm J Boehnlein DJ Bogert D Border PM Bower C Boyd S Buckley-Geer E Bungau C Byon-Wagner A Cabrera A Chapman JD Chase TR Cherdack D Chernichenko SK Childress S Choudhary BC 《Physical review letters》2006,97(19):191801
This Letter reports results from the MINOS experiment based on its initial exposure to neutrinos from the Fermilab NuMI beam. The rates and energy spectra of charged current nu(mu) interactions are compared in two detectors located along the beam axis at distances of 1 and 735 km. With 1.27 x 10(20) 120 GeV protons incident on the NuMI target, 215 events with energies below 30 GeV are observed at the Far Detector, compared to an expectation of 336+/-14 events. The data are consistent with nu(mu) disappearance via oscillations with |Delta(m)2/32|=2.74 +0.44/-0.26 x10(-3)eV(2) and sin(2)(2theta(23))>0.87 (68% C.L.). 相似文献
79.
James S. Bernstein 《应用光谱学评论》2013,48(1-2):119-137
Introduction Nuclear magnetic resonance (NMR) is a spectroscopic technique well suited to determining the structure of molecules ranging from a few atoms to large proteins. The strength of NMR lies in its ability to distinguish and identify atoms on the basis of their chemical environment, and in determining the chemical bond and spatial relationship of those atoms. Thus, NMR is a powerful tool for the identification of molecules, especially those of an organic nature. In addition, NMR has quantitative applications valuable to pharmaceutical analysis. 相似文献
80.
Abstract Rutherford backscattering (RBS) and ion induced X-ray (PIXE) channeling experiments have been used to study the damage accompanying Hg and Al implantations into Hg0.8Cd0.2 Te and its annealing as well as to determine the location of Hg in the crystal. The damage induced by the implantation of 300 keV Hg and 250 keV Al ions at room temperature was found from RBS channeling studies to reach a saturation level at doses of 1 × 1014 cm?2 and 3 × 1014 cm?2 respectively. The damage resembles that characteristic for extended defects and it anneals at ≈ 300°C. The location of the constituents of Hg implanted Hg0.8 Cd0.2 Te was studied by PIXE channeling observing the characteristic X-rays for each element. Angular scans indicate that the channels are mostly blocked by Hg atoms for both unannealed and, to a lesser extent, annealed crystals. This observation supports the suggestion that interstitial Hg atoms may be responsible for the conductivity of Hg implanted Hg1–x Cdg Te. 相似文献