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91.
92.
W M Hartmann 《The Journal of the Acoustical Society of America》1984,75(2):528-535
A central spectrum explanation of the existence of the binaural edge pitch [Klein and Hartmann, J. Acoust. Soc. Am. 70, 51-61 (1981)] appears to require central lateral inhibition in the human auditory system. We have looked for this effect in central masking experiments. Using the binaural-edge noise, which creates the binaural edge pitch, as a masker (in standard notation: No below and N pi above a phase boundary frequency), we measured pulsation thresholds for sine tones in two frequency ranges where the binaural edge pitch exists. We also obtained reference data, using the same pulsation threshold technique, for standard binaural conditions NoSo, NoS pi, N pi So, and N pi S pi. These data revealed masking level differences. Theoretically the difference between the binaural-edge thresholds and the reference data should show the peak and valley signature of lateral inhibition. No such structure was found. We suggest that this negative result does not exclude the possibility of central lateral inhibition, but that the time course of central lateral inhibition makes the pulsation threshold technique an inappropriate means for observing the effect. 相似文献
93.
β-Amino-vinyl-selenoketones 9 react with aryl acetic acidchlorides 11, N-iminoformyl-arylacetic-imidchlorides 15 or derivatives of cyano acetic acid to give unknown 6-aryl-2-selenopyrones 14, 6-aryl-2-(N-formamidino)-selenopyrylium salts 16 or 6-aryl-2-amino-selenopyrylium salts 19. The compounds 19 were prepared from 3-(β-chloro-vinyl)-acrylonitriles 3 and NaHSe, too. 相似文献
94.
95.
Yaschenko S Dymov S Kacharava A Komarov V Macharashvili G Rathmann F Barsov S Gebel R Hartmann M Khoukaz A Kulessa P Kulikov A Kurbatov V Lang N Lehmann I Lorentz B Mersmann T Merzliakov S Mikirtytchiants S Mussgiller A Nioradze M Ohm H Prasuhn D Schleichert R Seyfarth H Steffens E Stein HJ Ströher H Uzikov Y Zalikhanov B Zhuravlev N 《Physical review letters》2005,94(7):072304
A measurement of the analyzing power A(y) of the p-->d--> (p p) + n reaction was carried out at the ANKE spectrometer at COSY at beam energies of 0.5 and 0.8 GeV by detection of a fast forward proton pair of small excitation energy E(pp) < 3 MeV. The S-wave dominance in the fast diproton is experimentally demonstrated in this reaction. While at T(p) = 0.8 GeV the measured analyzing power almost vanishes, it rises to nearly unity at T(p) = 0.5 GeV for neutrons emitted at theta(c.m.)(n) = 167 degrees. The results are compared with a model taking into account one-nucleon exchange, single scattering, and Delta(1232) excitation in the intermediate state. The model describes fairly well the unpolarized cross section obtained earlier and the analyzing power at 0.8 GeV; it fails to reproduce A(y) at 0.5 GeV. 相似文献
96.
Reisdorf W Andronic A Gobbi A Hartmann ON Herrmann N Hildenbrand KD Kim YJ Kirejczyk M Koczoń P Kress T Leifels Y Schüttauf A Tymiński Z Xiao ZG Alard JP Barret V Basrak Z Bastid N Benabderrahmane ML Caplar R Crochet P Dupieux P Dzelalija M Fodor Z Grishkin Y Hong B Kecskemeti J Korolija M Kotte R Lebedev A Lopez X Merschmeyer M Mösner J Neubert W Pelte D Petrovici M Rami F de Schauenburg B Seres Z Sikora B Sim KS Simion V Siwek-Wilczyńska K Smolyankin V Stockmeier M Stoicea G Wagner P 《Physical review letters》2004,92(23):232301
We present a complete systematics (excitation functions and system-size dependences) of global stopping and side flow for heavy ion reactions in the energy range between 0.09A and 1.93A GeV. For the heaviest system, Au+Au, we observe a plateau of maximal stopping extending from about 0.2A to 0.8A GeV with a fast drop on both sides. The degree of stopping, which is shown to remain significantly below the expectations of a full stopping scenario, is found to be highly correlated to the amount of side flow. 相似文献
97.
Hartmann T Babilon M Kamerdzhiev S Litvinova E Savran D Volz S Zilges A 《Physical review letters》2004,93(19):192501
The electric dipole strength distribution in 44Ca has been measured up to 10 MeV in high resolution photon scattering experiments for the first time. The data obtained have been compared to earlier measurements on (40,48)Ca in order to view the evolution of the electric pygmy dipole resonance (PDR). Calculations that were performed within the framework of the microscopic extended theory of finite Fermi systems, which adds contributions of the quasiparticle-phonon coupling to random phase approximation calculations, give a qualitative agreement with the experimental data for all three isotopes. We have shown that it is necessary to include this coupling to describe the PDR. 相似文献
98.
Because of dispersion in head-related transfer functions (HRTFs), the interaural time difference (ITD) varies with frequency. This physical effect ought to have consequences for the size or shape of the auditory image of broadband noise because different frequency regions of the noise have different ITDs. However, virtual reality experiments suggest that human listeners are insensitive to head-related dispersion. The experiments of this article test that suggestion by experiments that isolate dispersion from amplitude effects in the HRTF and attempt to optimize the opportunity for detecting it. Nevertheless, the experiments find that the only effect of dispersion is to shift the lateralization of the auditory image. This negative result is explained in terms of the cross-correlation function for head-dispersed noise. Although the broad-band cross-correlation function differs considerably from 1.0, the cross-correlation functions within bands characteristic of auditory filters do not. A detailed study of the lateralization shifts show that the experimental shifts can be successfully calculated as an average of stimulus ITDs as weighted by Raatgever's frequency-weighting function (Thesis, Delft, The Netherlands, 1980). 相似文献
99.
Garçon S Vassiliou S Cavicchioli M Hartmann B Monteiro N Balme G 《The Journal of organic chemistry》2001,66(11):4069-4073
100.
The adsorption of various amino acids on zeolites with different structures was studied with regard to dependence of the pH value of the solution and the aluminum content of the zeolite in order to design tailor-made adsorbents for amino acid separations. 相似文献