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971.
It is shown that thin-film field effect transistors (FETs) made from amorphous (a-) silicon deposited by the glow-discharge technique have considerable potential as switching elements in addressable liquid crystal display panels. The fabrication of the elements and their characteristics with steady and pulsed applied potentials are discussed in some detail. Two important points are stressed: (i) a-Si device arrays can be produced by well-established photolithographic techniques, and (ii) satisfactory operation at applied voltages below 15VV is possible. Small experimental 7×5 transistor panels have been investigated and it is shown that with the present design up to 250-way multiplexing could be achieved. The reproducibility of FET characteristics is good and in tests so far no change has been observed after more than 109 switching operations.  相似文献   
972.
Resistivity and thermal conductivity of the intermediate valence compound CePd3 between 1.3 and 300 K are compared with those of the nonmagnetic and magnetic reference compounds YPd3 and GdPd3 and of alloys of the type Ce1xRE x Pd3 with RE=Y, Gd and 0.01<x<0.5. The analysis reveals the existence of a maximum metallic resistivity of 300 cm for CePd3. The intrinsic resistivity of CePd3 rises proportional toT 2 up to 100 K, with a coefficientB about 107 times larger than e.g. in copper. We interpret this with indirect electron-electron scattering mediated through valence transitions.  相似文献   
973.
Inclusive cross sections of η production by e+e- annihilation for c.m. energies between 4.0 and 5.0 GeV are presented. The η production is shown to be correlated with the production of a weakly decaying particle, indicating that its main source is F production. At the 4.42 GeV resonance it is correlated with a low energy photon, suggesting or production. A mass determination of the F is made at 4.42 GeV using the F → ηπ decay channel.  相似文献   
974.
Ternary and quaternary fission produced in silver and bromine nuclei have been studied withK5 nuclear emulsion exposed to 1.8 GeV/cK beams. The frequency of the ternary events is found to be ∼0.08 of that of the binary events produced in the same volume of the emulsion. The range ratio and range distribution of the fission fragments are studied and the angles between each pair of the fragments are determined. Ranges are found to vary from 5 to 40μ with a maximum number lying between 5 and 10μ. The angles between the fission fragments are found to form a broad distribution extending from 40° to 180°. A few of the events have also been analysed to give them a possible identity. A possible case of quaternary fission has also been reported. This paper was presented at the Symposium on 3rd High Energy Physics held at Bhubaneswar during November 1976.  相似文献   
975.
976.
Instantons and anti-instantons can profoundly influence the structure of a non-Abelian gauge theory involving N flavors of massless quarks. Interactions of the quarks with these pseudoparticles can spontaneously generate a quark mass, break the theory's SU(N) × SU(N) chiral symmetry and bind quark-antiquark pairs to form N2 ? 1 Goldstone bosons. If the spontaneously generated quark mass is small, multipseudoparticle configurations can be treated in a dilute gas approximation.  相似文献   
977.
Field experiments to investigate the attenuation of noise from single vehicles over short grass indicate that for a microphone height of 1·2 m and a source/receiver distance <30 m, the rate of attenuation is 4·8 dB(A) per doubling of distance. Some evidence is presented to suggest that for source/receiver distances >30 m the rate of attenuation increases with distance.  相似文献   
978.
We describe the results of a study of a TEA CO2 laser using a strip cylindrical unstable resonator which produces an output beam with suitable characteristics for producing a high quality line focus. Using this technique an irradiance of ?109W cm-2 over a 5 cm long line focus has been achieved.  相似文献   
979.
The S = 1 EPR spectrum for a tin-vacancy pair in silicon reveals easily detected isotope shifts in the fine structure splitting D for the various nuclear isotopes of tin (σD/D = + 1.0 × 10?4 per unit mass) as well as well as those for the six near neighbor silicon atoms (σD/D = ?0.67 × 10?4 per unit mass). These are attributed to the different vibrational amplitudes vs isotopic mass.  相似文献   
980.
The separated 2–5 lines of the Mössbauer spectrum of amorphous Fe90Zr10 alloys has been obtained from the linear combination of the spectra of unpolarized and magnetically polarized samples. The hyperfine field distribution has been determined from the original spectra and from the separated 2–5 lines using different evaluation methods (binomial distribution method. Fourier method and Window method).  相似文献   
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