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981.
R. Pfaff B. M. Young W. Benenson J. Clayton D. J. Morrissey N. A. Orr T. Reposeur M. Thoennessen J. A. Winger 《Zeitschrift für Physik A Hadrons and Nuclei》1993,347(1):67-70
A comparison has been made between the production of high energy (E γ≧30 MeV)γ rays from the bombardment of124Sn and112Sn targets withE/A= 10 MeV12C ions. The results are well explained by then-p bremsstrahlung model and do not indicate the need for any new processes. 相似文献
982.
Summary A finite crack propagating at constant speed in a functionally graded piezoelectric strip (FGPS) bonded to a homogeneous piezoelectric strip is considered. It is assumed that the electroelastic material properties of the FGPS vary exponentially across the thickness of the strip, and that the bimaterial strip is under combined anti-plane mechanical shear and in-plane electrical loads. The analysis is conducted for the electrically unified crack boundary condition, which includes both the traditional permeable and the impermeable ones. By using the Fourier transform, the problem is reduced to the solution of Fredholm integral equations of the second kind. Numerical results for the stress intensity factor and the crack sliding displacement are presented to show the influences of the crack propagation speed, electric loads, FGPS gradation, crack length, electromechanical coupling coefficient, properties of the bonded homogeneous piezoelectric strip and crack location. 相似文献
983.
984.
985.
The fuzzification of a positive implicative filter is considered, and some of properties are investigated. The relation among fuzzy filter, fuzzyn-fold implicative filter, and fuzzyn-fold positive implicative filter is discussed. 相似文献
986.
R. Albrecht T. C. Awes C. Baktash P. Beckmann F. Berger R. Bock G. Claesson G. Clewing L. Dragon R. L. Ferguson A. Franz S. Garpman R. Glasow H. ?. Gustafsson H. H. Gutbrod K. H. Kampert B. W. Kolb P. Kristiansson I. Y. Lee H. L?hner I. Lund F. E. Obershain A. Oskarsson I. Otterlund T. Peitzmann S. Persson F. Plasil A. M. Poskanzer M. Purschke H. G. Ritter R. Santo H. R. Schmidt T. Siemiarczuk S. P. S?rensen E. Stenlund G. R. Young WA Collaboration 《Zeitschrift fur Physik C Particles and Fields》1990,47(3):367-375
The production of neutral pions by the interaction of 200A·GeV p and16O projectiles with a Au target has been studied in the pseudorapidity range 1.5≦η≦2.1. Transverse momentum spectra have been measured between 0.4 GeV/c and 3.6 GeV/c and their dependence on the centrality of the collision has been investigated. The peripheral-collision spectra display a marked change of slope with a hard component starting at about 1.8 GeV/c, in contrast to central-collision data. The data are discussed in comparison to p+p and α+α data from the ISR. 相似文献
987.
Jason Glenn Christopher K. Walker Erick T. Young 《International Journal of Infrared and Millimeter Waves》1997,18(2):285-300
We present the design of a broad band, 1.3 mm polarimeter for astronomical observations and the results of first light observations
at the Heinrich Hertz Telescope (HHT). The systematic polarization of the instrument plus telescope is 1.1%. The observed
linear polarization of DR 21,P=1.65%±0.14% andθ=16°±2°, is consistent with previous measurements. Our 0.9% upper limit on the linear polarization of Cepheus A is the first
1.3 mm measurement reported. With Cyclops it is possible to map the magnetic fields in several of the brightest molecular
cloud dust cores in the Milky Way. We comment on the expected performance of an achromatic Rexolite half-waveplate for λ=800μm to 1.3 mm. 相似文献
988.
In general, the sup-min convolution has been used for fuzzy arithmetic to analyze fuzzy system reliability, where the reliability of each system component is represented by fuzzy numbers. It is well known that Tω-based addition preserves the shape of L-R type fuzzy numbers. In this paper, we show Tω-based multiplication also preserves the shape of L-R type fuzzy numbers. We then apply Tω-based arithmetic operations to fuzzy system reliability analysis. In fact, we show that we can simplify fuzzy arithmetic operations and even get the exact solutions for L-R type fuzzy system reliability, while others [Singer, Fuzzy Sets Syst. 34 (1990) 145; Cheng and Mon, Fuzzy Sets Syst. 56 (1993) 29; Chen, Fuzzy Sets Syst. 64 (1994) 31] have got the approximate solutions using sup-min convolution for evaluating fuzzy system reliability. 相似文献
989.
Yoon Soo Han Sang Dae Kim Lee Soon Park Dong Uk Kim Younghwan Kwon 《Journal of polymer science. Part A, Polymer chemistry》2003,41(16):2502-2511
Four different types of conjugated copolymers, consisting of alternating structures of phenothiazinylene vinylene and phenylene vinylene derivatives such as phenylene vinylene, 1,1′‐biphenyl‐4,4′‐ylene vinylene, 2‐methoxy‐5‐(2‐ethylhexyloxy)‐1,4‐phenylene vinylene, and 9,10‐anthrylene vinylene, were prepared by Horner–Emmons condensation between appropriate diphosphonates and dialdehydes. Single‐layer and double‐layer light‐emitting diodes were fabricated with the synthesized conjugated polymers, and their electroluminescent properties were investigated. Poly(N‐2‐ethylhexyl‐3,6‐phenothiazinylene vinylene‐alt‐9,10‐anthrylene vinylene), containing phenothiazinylene vinylene and anthrylene vinylene as repeat units, emitted a reddish‐orange color with Commission Internationale de l'Eclairage coordinates of x = 0.6173 and y = 0.3814 that was very similar to the National Television System Committee standard red, and it showed a bipolar carrier‐injection/transporting capability caused by electron‐withdrawing anthracene and electron‐donating amino groups. Poly[N‐2‐ethylhexyl‐3,6‐phenothiazinylene vinylene‐alt‐2‐methoxy‐5‐(2‐ethylhexyloxy)‐1,4‐phenylene vinylene], containing phenothiazinylene vinylene and dialkoxy phenylene vinylene moieties, showed excellent hole‐injection/transporting capability. © 2003 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 41: 2502–2511, 2003 相似文献
990.
Chun‐Hsiung Chien Yu‐Hsu Chang Chih‐Pin Tsai Chih‐Wei Peng Lung‐Shen Wang Pei‐Sun Sheng Chi‐Young Lee Hsin‐Tien Chiu 《中国化学会会志》2006,53(2):287-292
Black solid precursors obtained from reactions between MCl5 (M = Nb, Ta) and alkyllithiums, n‐butyllithium (nBuLi) and ethyllithium (EtLi), in tetrahydrofuran (THF) were heat treated under vacuum at 673–973 K to form nano‐sized particles (20–100 nm in diameter) of lithium niobate (LiNbO3) and lithium tantalate (LiTaO3). Stoichiometry of the reactants is critical and affects the phases of the products. Based on the volatile byproducts detected, a reaction pathway involving the activation of THF by alkyllithiums is proposed to be important for the formation of LiNbO3 and LiTaO3 precursors. 相似文献