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411.
E. A. Doroshkevich M. A. Bashkanov H. Clement E. Perez del Rio A. Pricking T. Yu. Skorodko G. J. Wagner 《Physics of Atomic Nuclei》2014,77(7):936-940
Despite the number of inclusive measurements of the pionic fusion reactions, the nature of the ABC effect discovered in 1960 was not completely established. Exclusive measurements of the doublepion-production reactions leading to either fused d, 3He and 4He nuclear final states or pp pairs are analyzed. A significant ABC effect—enhancement in the region of low ππ mass—is found only in the isoscalar ππ channel while in the isovector channels it is small or absent. For the reaction with isovector pp final state an ABC effect was not observed even at the special kinematic conditions to reproduce a quasi-bound two-proton state. The total cross sections for the d and 4He fusion reactions show similar resonance-like energy dependence. 相似文献
412.
Simon Clement Sergio Bellizzi Bruno Cochelin Guillaume Ricciardi 《Journal of sound and vibration》2014
The Proper Orthogonal Decomposition (POD) method is a tool well adapted to analyze vector signals whereas Continuous Gabor Transform (CGT) is suitable for scalar signal with multi-frequency components. In this paper, a method named Sliding Window Proper Orthogonal Decomposition (SWPOD) combining POD and CGT to analyze Multi-Degrees-Of-Freedom (MDOF) vibration system responses is presented. SWPOD gives access to the evolution of the coherent spacial structures and their frequency components versus time. The method is of principal interest in the case of swept-sine excitation of linear or nonlinear systems to access the resonance frequencies, mode shapes and modal damping ratios. A procedure is proposed to extract the linear and nonlinear normal modes of weakly damped MDOF mechanical systems and illustrated using numerical examples. 相似文献
413.
414.
T. Skorodko M. Bashkanov D. Bogoslawsky H. Calén H. Clement E. Doroshkevich L. Demiroers C. Ekström K. Fransson L. Gustafsson B. Höistad G. Ivanov M. Jacewicz E. Jiganov T. Johansson O. Khakimova S. Keleta I. Koch F. Kren S. Kullander A. Kupść P. Marciniewski R. Meier B. Morosov C. Pauly H. Petrén Y. Petukhov A. Povtorejko R. J. M. Y. Ruber K. Schönning W. Scobel B. Shwartz J. Stepaniak P. Thörngren-Engblom V. Tikhomirov G. J. Wagner M. Wolke A. Yamamoto J. Zabierowski J. Zlomanczuk 《The European Physical Journal A - Hadrons and Nuclei》2011,47(9):1-6
First exclusive data for the $\ensuremath{pp \to nn\pi^+\pi^+}$ reaction have been obtained at CELSIUS with the WASA detector setup at a beam energy of Tp = 1.1 GeV. Total and differential cross-sections disagree with theoretical calculations, which predict the $ \Delta$ $ \Delta$ excitation to be the dominant process at this beam energy. Instead, the data require the excitation of one of the nucleons to a higher-lying $ \Delta$ state, preferably the $\ensuremath{\Delta(1600)P_{33}}$ , to be the leading process. 相似文献
415.
U. Siodlaczek P. Achenbach J. Ahrens H.-J. Arends R. Beck R. Bilger H. Clement V. Hejny J.D. Kellie M. Kotulla B. Krusche V. Kuhr R. Leukel J.C. McGeorge V. Metag R. Novotny V. Olmos de León F. Rambo M. Schepkin A. Schmidt H. Ströher G.J. Wagner Th. Walcher J. Weiß F. Wissmann M. Wolf 《The European Physical Journal A - Hadrons and Nuclei》2000,9(3):309-311
The reaction γd↦π0
X has been measured with TAPS at MAMI in the energy range E
γ = 140-300 MeV. Using the Glasgow tagging spectrometer a photon energy resolution of 0.8 MeV was achieved. The energy excitation
functions of integral and differential total cross-sections show no structures of statistical significance > 2σ. Upper limits
for the production of narrow isoscalar or isovector dibaryons with masses m? 2100 MeV/c2 were deduced. They are in the range 2-5 μb averaged over the 0.8 MeV energy resolution.
Received: 25 October 2000 / Accepted: 24 November 2000 相似文献
416.
Kristiane M. Van Lierde Sophia De Ley Gregory Clement Marc De Bodt Paul Van Cauwenberge 《Journal of voice》2004,18(4):467-474
A relatively new management strategy for the treatment of voice disorders is the use of laryngeal manual therapy. The main purpose of the present pilot study is to document the outcome of vocal quality after a well-defined laryngeal manual therapy (LMT) program. Four Dutch professional voice users with a persistent moderate or severe muscle tension dysphonia were studied pretreatment (1 week before LMT) and posttreatment (1 week) after completion of manual therapy (25 sessions). These subjects had received several months of traditional voice therapy, without any success. To measure and compare, the effect of LMT objective and subjective assessment techniques were used. Perceptual voice assessment included a perceptual rating of the voice using the GRBAS scale. Furthermore, the vocal quality in this population was modeled by means of the Dysphonia Severity Index (DSI). All of the subjects selected for LMT showed improvement in perceptual vocal quality and DSI values. As the DSI is a weighted variable including aerodynamic and acoustic measures, small improvements (closer to 5) are very indicative of vocal quality improvement.1 The use of LMT in professional voice users with persistent moderate-to-severe muscle tension dysphonia, especially in some subjects who have not responded to traditional voice therapy, is supported by this pilot study. 相似文献
417.
H. Clement R. Frick G. Graw P. Schiemenz N. Seichert 《Zeitschrift für Physik A Hadrons and Nuclei》1983,314(1):49-53
The 2 1 + -excitation of deformed nuclei by tensor polarized deuterons provides an alignment of both nuclei and thus a means to study specifically the quadrupole-quadrupole interaction between both nuclei. The tensor analyzing powerA xz (θ) has been measured for the elastic and inelastic scattering on24Mg and28Si. The coupled channel analysis including a deformed tensor potential reveals a clear signature of the quadrupole-quadrupole part of the nuclear projectile-target interaction. 相似文献
418.
Iodine-mediated cyclization of benzo[c]thiophene aldehyde with 1,2-diphenylamine/2-aminophenylthiol led to the formation of benzimidazole/benzothiazole-incorporated benzo[c]thiophenes. Similarly, reaction of benzo[c]thiophene aldehyde with p-toluenesulfonylmethyl isocyanide (TOSMIC) reagent in the presence of K2CO3 as a base furnished oxazole-containing benzo[c]thiophene analogs. 相似文献
419.
420.