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101.
Electrical resistance measurements are reported for amorphous In20Te80 and Cu25Au5Te70 alloys up to a pressure of 80 Kbar using a Bridgman anvil apparatus and a four lead arrangement to measure resistances. The amorphous samples are produced by liquisol quenching. The resistance shows time dependent changes which are analysed in detail. The contention that there is a pressure-induced transformation from the amorphous to the crystalline phase is confirmed by X-ray diffraction of samples recovered after they were pressurised to 35 Kbar in a hydrostatic environment. 相似文献
102.
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104.
Summary Dichlorobis(cyclopentadienyl)titanium(IV), Cp2TiCI2, reacts with bidentate Schiff bases such as salicylideneaniline, salicylidene-o-toluidine, salicylidene-m-toluidine, salicylidene-p-toluidine and 2-hydroxy-l-naphthylReprints of this paper are not available.To whom all correspondence should be addressed. 相似文献
105.
Hari Gopal Mukerjee 《Fresenius' Journal of Analytical Chemistry》1959,167(3):182-184
Summary Migration rate of ions increases with voltage. Nickel ion migrates in 0.5 Molar tartaric acid medium in a small well compact zone leaving no trailing and can be easily quantitatively estimated colorimetrically.Part II: Sec Z. analyt. Chem. 163, 408 (1958). 相似文献
106.
The reactivities of the stoichiometric and partially reduced rutile TiO2(110) surfaces towards oxygen adsorption and carbon monoxide oxidation have been studied by means of periodic density functional theory calculations within the Car-Parrinello approach. O2 adsorption as well as CO oxidation are found to take place only in the presence of surface oxygen vacancies (partially reduced surface). The oxidation of CO by molecularly adsorbed O2 at the O-vacancy site is found to have an activation energy of about 0.4 eV. When the adsorbed O2 is dissociated, the resulting adatoms can oxidize incoming gas-phase CO molecules with no barrier. In all studied cases, once CO is oxidized to form CO2, the resulting surface is defect-free and no catalytic cycle can be established. 相似文献
107.
We study J/psi production in pp collisions at BNL Relativistic Heavy Ion Collider (RHIC) within the PHENIX detector acceptance range using the color singlet and color octet mechanism which are based on perturbative QCD and nonrelativistic QCD. Here we show that the color octet mechanism reproduces the RHIC data for J/psi production in pp collisions with respect to the p(T) distribution, the rapidity distribution, and the total cross section at square root = 200 GeV. The color singlet mechanism leads to a relatively small contribution to the total cross section when compared to the octet contribution. 相似文献
108.
Zepf M Clark EL Beg FN Clarke RJ Dangor AE Gopal A Krushelnick K Norreys PA Tatarakis M Wagner U Wei MS 《Physical review letters》2003,90(6):064801
Measurements of energetic proton production resulting from the interaction of high-intensity laser pulses with foil targets are described. Through the use of layered foil targets and heating of the target material we are able to distinguish three distinct populations of protons. One high energy population is associated with a proton source near the front surface of the target and is observed to be emitted with a characteristic ring structure. A source of typically lower energy, lower divergence protons originates from the rear surface of the target. Finally, a qualitatively separate source of even lower energy protons and ions is observed with a large divergence. Acceleration mechanisms for these separate sources are discussed. 相似文献
109.
Arena DA Bartynski RA Nayak RA Weiss AH Hulbert SL Weinert M 《Physical review letters》2003,91(17):176403
The Pd M4VV and M5VV Auger spectra of the 0.1 ML Pd/Ag(100) dilute surface alloy have been measured using Auger-photoelectron coincidence spectroscopy. The M4VV spectrum indicates that Pd 3d(3/2) core holes have a Coster-Kronig decay rate that is approximately 10 times that of Pd metal. Our calculations show that this giant enhancement arises from the local electronic structure of excited Pd atoms at the surface. Anomalous features in the Auger line shape are similar to those seen in dilute bulk PdAg alloys, and these features in the M5VV and M4VV lines are in good agreement with theoretical predictions. 相似文献
110.
Nayak C 《Physical review letters》2000,85(1):178-181
We show that slave particles are always confined in U(1) gauge theories of interacting electron systems. Consequently, the low-lying degrees of freedom are different from the slave particles. This is done by constructing a dual formulation of the slave-particle representation in which the no-double-occupancy constraint becomes linear and, hence, soluble. Spin-charge separation, if it occurs, is due to the existence of solitons with fractional quantum numbers in a particular dual action. 相似文献