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Delayed fission events due to isomeric fission have been produced using He3 and He4 beams from the MP Tandem Van de Graaff accelerator. The isomeric nuclei which recoil from the target and subsequently fission in flight were detected by a square cone array of polycarbonate foil detectors mounted along the beam direction. From the distribution of fission tracks along the detector foils, half-lives in the nanosecond region were deduced.  相似文献   
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Using the solenoidal magnetic detector PLUTO, we have measured the total cross section for e+e? annihilation into hadrons. Results are presented for center of mass energies between 3.6 and 4.8 GeV, and in the regions of the Jψ(3.1) and ψ(3.7) resonances. We also present results for the 2 prong cross section in the energy range 3.6 to 4.8 GeV.  相似文献   
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Part I of this paper presented the basic concepts of behavior settings and eco-behavioral science originated by the psychologist Roger Barker, showed how they could be linked with standard economic data systems, and suggested their use as a basis for time-allocation matrices and social system accounts. Part II discusses the relationships of behavior settings and eco-behavioral science to established disciplines, describes applications of mathematics to the new concepts by Fox and associates, and points out some major areas in need of mathematical and theoretical development. These areas include representation and measurement of patterns of relationships among roles within behavior settings, relationships among behavior settings within communities and organizations, and the evolution of large, heterogeneous populations of behavior settings over time. We hope some readers will be motivated to participate in this new scientific enterprise.  相似文献   
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Until recently, speech analysis techniques have been built around the all-pole linear predictive model. This study examines the effectiveness of using the perceptual linear predictive method for analyzing nasal consonants. Six speakers (three men and three women) produced 300 CV syllables with initial nasal consonants /m/ and /n/. A threshold-based boundary detection algorithm was developed to extract nasal segments from the CV contexts. Poles of a fifth-order perceptual linear predictive model were calculated and the frequency of the second pole was used to characterize the place of articulation of nasal consonants. Results indicated that the frequency for the second transformed pole was significantly lower for /m/ than for /n/ and was independent of factors such as a vowel context and gender of the speaker. A nasal identification rate of 86% was obtained based on the frequency of the second pole. The use of the perceptual linear predictive method may thus overcome some difficulties associated with analyzing nasal consonants.  相似文献   
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Diemair  W.  Fox  H. 《Mikrochimica acta》1939,26(4):343-348
Microchimica Acta - Betrachtet man zusammenfassend die vorstehenden Versuchsergebnisse, so ergibt sich:  相似文献   
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