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991.
Jürgen Schmidt 《Archiv der Mathematik》1965,16(1):407-411
Ohne Zusammenfassung 相似文献
992.
This study investigated the effects of prolonged loud reading on trained and untrained subjects. Subjects were eight young women singers, and eight young women with limited musical experience. Each subject underwent videostroboscopic examination prior to and following 1 h of prolonged loud reading. The pretest and posttest videotaped samples were randomized and presented to three experienced judges, who evaluated various aspects of laryngeal appearance and vibratory characteristics. Analyses of group data revealed that untrained subjects showed a small but significant increase in amplitude of vocal fold excursion following the experimental task. No significant differences were noted in the trained singer group. When individual variation was analyzed, it was found that most subjects did not show many changes from pretest to posttest. It was concluded that a l-h loud-reading task was not sufficient to induce notable laryngeal alterations 相似文献
993.
G. Wolf J. Lerchner H. Schmidt H. Gamsjäger E. Königsberger P. Schmidt 《Journal of Thermal Analysis and Calorimetry》1996,46(2):353-359
Thermodynamic quantities of the aragonite → calcite transition, were evaluated using results of calorimetric investigations. (1) Dissolution enthalpies of the CaCO3 polymorphs aragonite and calcite measured near room temperature with different calorimeter, (2) the enthalpy of the spontaneous phase transformation obtained by differential scanning calorimetry, (3) heat capacities and heat capacity differences determined with a heat flux calorimeter as well as previously determined, (4)e.m.f. data on Gibbs-energies of the phase transition were processed simultaneously with an optimization routine developed recently. The optimized data set (25°C) given below corresponds reasonably with CODATA recommendations, however, the precision has markedly improved. 相似文献
994.
995.
Gottfried Mrkl Andreas Pll Norbert G. Aschenbrenner Corinna Schmaus Theodor Troll Peter Kreitmeier Heinrich Nth Martin Schmidt 《Helvetica chimica acta》1996,79(5):1497-1517
Extremely Expanded Tetrathiafulvalenes with Polyene Spacers. Carotinoid Tetrathiafulvalenes. Polymethin-Tetracyanotetrathiafulvalene Radical Cations, a New Class of Violenes The synthesis of extended tetrathiafulvalenes 11 with di-, tetra-, hexa-, octa-, deca- and dodecamethine spacers is described by a PPh3-induced Wittig-reaction-like condensation of the corresponding polyenedials 10 with 2-thio-1,3-dithiole-4,5-dicarbonitrile ( 9 ). By the same procedure, the dimethyloctamethine- and the tetramethyl-hexadecamethine-tetrathiafulvalenes 14 and 15 , respectively, were obtained. The extended tetrathiafulvalenes represent multistep vinylogous redox systems of the ‘violene type’. They can be oxidized to give the cyanine-like radical cations, e.g. 11 sem, 14 sem, and 15 sem, and the dications, e.g. 11 ox, 14 ox, and 15 ox; their UV/VIS/NIR spectra are reported. The crystal and molecular structure of (all-E)-2,2′-(octa-2,4,6-trien-1,8-diylidene)bis[1,3-dithiole-4,5-dicarbonitrile] ( 11e ) was determined: it is a rod-like, planar molecule; in the crystal, it forms staples along the longest molecule axis. The CV measurements confirm that the redox potentials of 11, 14 , and 15 decrease asymptotically with the increasing length of the spacer. Because of the close relationship of the extended tetrathiafulvalenes (ETTF's) to the carotinoids, they are named ‘caroviologenes’; they formally belong to the class of molecular wires. 相似文献
996.
997.
We present the first experimental investigation of the photoionization in Pd I using the synchroton radiation facility of the 800 MeV electron storage ring in Berlin (BESSY) and atomic beam technique. The experiments have been concentrated on the study of the Rydberg series of autoionizing levels and nf which lie between the two 4d thresholds. 相似文献
998.
A. Mheemeed K. Schreckenbach G. Barreau H.R. Faust H.G. Börner R. Brissot P. Hungerford H.H. Schmidt H.J. Scheerer T. Von Egidy K. Heyde J.L. Wood P. Van Isacker M. Waroquier G. Wenes M.L. Stelts 《Nuclear Physics A》1984,412(1):113-140
Gamma rays and conversion electrons have been measured following thermal neutron capture in 113Cd using the crystal spectrometers GAMS and the β-spectrometer BILL at the High Flux Reactor of the ILL at Grenoble. Primary γ-rays following thermal and average resonance neutron capture at En = 2 keV and 24 keV were recorded at the High Flux Beam Reactor at the Brookhaven National Laboratory. The 113Cd(d, p)114Cd reaction was studied with the Q3D spectrograph at the Munich tandem accelerator. Combining all these experimental results an almost complete level scheme of 114Cd was constructed up to 3.3 MeV including 48 excited levels with spin and parity information. The level scheme is discussed in terms of particle-hole excitations across the Z = 50 closed shell coupled to collective states, as well as in an interacting boson configuration mixing scheme. 相似文献
999.
The reaction of NO with CO on Rh(111) has been studied with temperature programmed reaction (TPR). Comparisons are made with the reaction of O2 with CO and the reaction of NO with H2. The rate-determining step for both CO oxidation reactions is CO(a) + O(a) → CO2(g). Repulsive interactions between adsorbed CO and adsorbed nitrogen atoms lead to desorption of CO in a peak at 415 K which is in the temperature range where the reaction between CO(a) and O(a) produces CO2(g). Thus the extent of reaction of CO(a) with NO(a) is less than that between CO(a) and O(a) due to the lower coverage of CO caused by adsorbed N atoms and NO. A similar repulsive interaction between NO(a) and H(a) suppresses the NO + H2 reaction. CO + NO reaction behavior on Rh(111) is compared to that observed on Pt(111). 相似文献
1000.