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51.
Dieter Klapstein Robert Kuhn John P. Maier Liubomir Misev Martin Ochsner 《Helvetica chimica acta》1984,67(5):1222-1232
Gas phase emission and laser excitation spectra of the Ã2E?X?2E (Σ = +½, ?½) transition of rotationally/vibrationally cooled 1-chloro- and 1-bromo-1,3-pentadiyne cations have been obtained. The emission was excited by electron impact on a seeded helium supersonic free jet and the fluorescence by laser excitation of cations produced by Penning ionization and collisional relaxation. From these two sets of data the origin bands of the spin-orbit systems are located and for the bromo species this leads to better values of the spin-orbit splitttings in the two electronic states and of the first adiabatic ionization energy. The vibrational frequencies of many of the fundamentals of these cations in the X?2E and Ã2E states have been obtained to within ±2 cm?1. 相似文献
52.
53.
R. Kuhn 《Colloid and polymer science》1978,256(3):300-301
Ohne Zusammenfassung 相似文献
54.
Peter Kuhn Ulrich Hauser Wolfgang Neuwirth 《Zeitschrift für Physik A Hadrons and Nuclei》1973,264(4):287-300
The Mössbauer spectra of Fe(CO)5 dissolved in 39 organic solvents were investigated. An influence on the quadrupole split was found only for those solvents containing carbonylic CO, but not for solvents containing another polar group. The change of the quadrupole split means always a reduction and is independent of temperature. The concentration dependence of the additional split indicates that it is caused only by nearest neighbours.—These results give a hint for a specific weak interaction between the carbonylic CO group of Fe(CO)5 and the solvents. This cannot be a general dipole-dipole interaction because of the missing influence of other polar solvents, so that a weak chemical bond is suggested. 相似文献
55.
Two experimental arrangements of an optical frequency up-converter using GaSe are described. Two wavelength regions have been covered by series of monochromatique rays (one ranging from 3.25 μ to 3.85 μ, the other one from 0.954 μ to 0.968 μ). 相似文献
56.
G. Ransoné P. Sixel H.H. Kaufmann R. Klein H. Vogt H. Dreverman D. Kuhn J.P. Porte R.T. Ross F. Triantis K. Dziunikowska B. Muryn K.W.J. Barnham J. Wells P.R.S. Wright D. Dallman F. Mandl M. Szczekowski 《Nuclear Physics B》1980,167(3):285-291
The charged multiplicity distribution is presented for K?p interactions produced in the hydrogen bubble chamber, BEBC, using an r.f. separated, tagged K? beam of 110 GeV/c momentum. A comparison with K+p, πp and pp data at lower energies shows that the main features of the multiplicity distributions depend on energy and charge of the incident particles, but not on their strangeness. At high energies, only the energy is important. 相似文献
57.
R. Kuhn F. A. Neugebauer H. Trischmann 《Monatshefte für Chemie / Chemical Monthly》1966,97(4):1280-1289
Zusammenfassung Verdazyle reagieren mit FeCl3 und anderen Metallhalogeniden in HCOOH unter Bildung von Doppelsalzen. Mit Tetranitromethan erhält man Verdazylium; C(NO2)3
; und Verdazylium;NO3
;. Verdazyliumsalze und Tetramethyl-p-phenylendiamin ergeben unter Elektronenübergang Verdazyle undWursters Blau. Dabei werden aus 2 diamagnetischen Verbindungen 2 paramagnetische Radikale gebildet. Die Absorptionsspektren verschiedenartig substituierter Verdazyliumsalze werden im Zusammenhang mit den Spektren der entsprechenden Verdazyle diskutiert.
10. Mitt.:F. A. Neugebauer, Mh. Chem.97, 853 (1966). 相似文献
Verdazyls react with FeCl3 and other metal halides in formic acid to give double-salts. Verdazylium;·C(NO2)3 ; and Verdazylium;NO3 ; were obtained with tetranitromethane. Verdazyliumsalts and tetramethyl-p-phenylenediamine yield, in an electron transfer reaction, the corresponding verdazyls andWurster's-blue; i. e. two diamagnetic compounds react to give two stable paramagnetic species. The absorption spectra of different substituted verdazylium salts are discussed in relation to the spectra of the corresponding verdazyls.
10. Mitt.:F. A. Neugebauer, Mh. Chem.97, 853 (1966). 相似文献
58.
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60.
Zuckerwar AJ Kuhn TR Serbyn RM 《The Journal of the Acoustical Society of America》2003,113(6):3179-3187
Background noise studies have been extended from air condenser microphones to piezoresistive, electret condenser, and ceramic microphones. Theoretical models of the respective noise sources within each microphone are developed and are used to derive analytical expressions for the noise power spectral density for each type. Several additional noise sources for the piezoresistive and electret microphones, beyond what had previously been considered, were applied to the models and were found to contribute significantly to the total noise power spectral density. Experimental background noise measurements were taken using an upgraded acoustic isolation vessel and data acquisition system, and the results were compared to the theoretically obtained expressions. The models were found to yield power spectral densities consistent with the experimental results. The measurements reveal that the 1/f noise coefficient is strongly correlated with the diaphragm damping resistance, irrespective of the detection technology, i.e., air condenser, piezoresistive, etc. This conclusion has profound implications upon the expected 1/f noise component of micromachined (MEMS) microphones. 相似文献