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991.
Hartouni E.P. Jensen D.A. Klima B. Kreisler M.N. Rabin M.S.Z. Uribe J. Church M. Gara A. Gottschalk E. Hylton R. Knapp B.C. Sippach F.W. Stern B. Wiencke L. Christian D. Gutierrez G. Holmes S.D. Strait J.B. Wehmann A. Avilez C. Correa W. Rosales A. Forbush M. Huson F.R. White J. 《IEEE transactions on nuclear science》1989,36(5):1480-1484
A novel technique for both online and offline computation is presented. With this technique, a reconstruction analysis in elementary particle physics, otherwise prohibitively long, has been accomplished. It will be used online in an upcoming Fermilab experiment to reconstruct more than 100000 events per second and to trigger on the basis of that information. The technique delivers 40 gigaoperations per second, has a bandwidth on the order of gigabytes per second, and has a modest cost. An overview of the program, details of the system, and performance measurements are presented 相似文献
992.
S. J. Pearton K. P. Lee M. E. Overberg C. R. Abernathy N. Theodoropoulou A. F. Hebard R. G. Wilson S. N. G. Chu J. M. Zavada 《Journal of Electronic Materials》2002,31(5):336-339
High concentrations (0.1–5 at.%) of Mn or Fe were introduced into the near-surface region (≤2000 Å) of 6H-SiC substrates by direct implantation at ~300°C. After annealing at temperatures up to 1000°C, the structural properties were examined by transmission electron microscopy (TEM) and selected-area diffraction pattern (SADP) analysis. The magnetic properties were examined by SQUID magnetometry. While the Mn-implanted samples were paramagnetic over the entire dose range investigated, the Fe-implanted material displayed a ferromagnetic contribution present at <175 K for the highest dose conditions. No secondary phases were detected, at least not to the sensitivity of TEM or SADP. 相似文献
993.
C. N. Cacaval E. C. BuruianÎ D. Rou E. Rusu G. E. Grigoriu V. Brboiu 《Polymer International》1985,17(4):343-346
Thermogravimetry and pyrolysis in combination with gas chromatography and infrared spectroscopy were the experimental techniques applied to the thermal degradation of cinnamoylated poly(vinyl alcohol) samples, constituted from vinyl alcohol-vinyl cinnamate photocrosslinkable copolymers. The thermal decomposition products include gases, liquids and solids. The gases are formed from saturated and unsaturated volatile hydrocarbons C1? C4, carbon monoxide and carbon dioxide. The liquid fraction includes aromatic hydrocarbons and some oxygenated organic compounds. The solid product identified in the greatest amount was cinnamic acid. The content in the thermal decomposition products varies considerably both with copolymer composition and temperature. 相似文献
994.
The viscoelastic properties of a three-arm and a four-arm star polybutadiene with the same arm molecular weight (Ma) were studied. The zero-shear recoverable compliance (J0e) and plateau modulus (G0N) for these stars are the same. The zero-shear viscosity (η0) of the three-arm star is 20% lower than that of the four-arm star. Mixtures of the stars had J0e and G0N unchanged. A mixture of the three- and four-arm star was diluted with a low molecular weight linear polybutadiene. G0N∝ø2; J0e∝ø?1 and Me∝ø?1, as expected for dilution with a θ-solvent. 相似文献
995.
The noise generated by a ball mill during a batch grinding operation is investigated and the results show that, for a given ore, the noise levels may vary with time of grind, ore charge weight and mill speed. The role of the ore in absorbing noise energy is suggested as a possible control variable for the grinding process and as an indicator of product size distribution. The relationship between ore types and mill noise is also examined and, under conditions of wet grinding, it is demonstrated that mill noise analysis can indicate ore type and may have a possible use as a grindability-type parameter. 相似文献
996.
997.
N. N. Aizenberg É. I. Gergo Yu. L. Ivas'kiv I. V. Semion 《Cybernetics and Systems Analysis》1991,27(4):491-496
We propose a new class of tunable logic modules that realize functions of k-valued logic. These modules are characterized by homogeneous structure and linear dependence of the number of tunable inputs on the number of input variables.Translated from Kibernetika i Sistemnyi Analiz, No. 4, pp. 24–29, July–August, 1991. 相似文献
998.
999.
B. L. WEDZICHA S. GODDARD D. N. GARNER 《International Journal of Food Science & Technology》1987,22(6):653-657
When sulphur dioxide inhibits the enzymic browning of catechol catalysed by mushroom tyrosinase, the main reaction product is 4-sulphocatechol. When assessed for its browning potential, this product appears to be unreactive and does not inhibit the enzyme. 相似文献
1000.
By applying a high-reflectivity metal coating to the rear facet of a GaAs-based quantum cascade laser operating at /spl lambda//spl sim/11.5 /spl mu/m, the threshold current has been reduced by 11% at 260 K and pulsed operation of the epilayer-up mounted device was extended from 283 to 294 K. 相似文献