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The relative cross section for the gas phase photodetachment of electrons has been determined for nitrite ions in the wavelength region 280–740 nm (4.43-1.68 eV). The vertical detachment energy for ONO? has been determined to be ≈ 2.8 eV. Evidence is presented for a new isomer of NO?2. 相似文献
125.
Angular-resolved photoemission spectra from a sulphur layer on Pd(100) reveal peaks independent of photon energy, which show strong dispersion in the electron energy range 3…9 eV relative to the vacuum level. The appearance of these levels can be correlated with absolute gaps in the projected bulk band structure of palladium. We interpret these features, which are also observed in secondary electron emission, as adsorbate-induced surface resonances above EF. The sulphur 3p-derived levels below EF show strong dispersion effects in the [110] but not in the [100] crystal azimuth. The projected band structure also shows that hybridisation gives rise to an absolute gap at approximately this energy in the [110] direction. 相似文献
126.
The heat capacities and enthalpies of Cu2Te(c), CuTe(c), Ag2Te(c) and Ag1.64Te(c) have been measured for the temperature range (280–8OO K) using differential scanning calorimetry. Several transitions were observed in these substances and the enthalpies associated with these transitions have been determined. 相似文献
127.
Roger W. Barnard Clint Richardson Alexander Yu. Solynin 《Proceedings of the American Mathematical Society》2005,133(7):2091-2099
For the standard class of normalized univalent functions analytic in the unit disk , we consider a problem on the minimal area of the image concentrated in any given half-plane. This question is related to a well-known problem posed by A. W. Goodman in 1949 that regards minimizing area covered by analytic univalent functions under certain geometric constraints. An interesting aspect of this problem is the unexpected behavior of the candidates for extremal functions constructed via geometric considerations.
128.
Richardson ML 《Talanta》1967,14(3):385-391
The analytical chemistry of cyclamates is reviewed, the emphasis being on methods of assay, tests for impurities and methods of determination in food and drug products. 相似文献
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K. V. Richardson 《The Journal of the Operational Research Society》1970,21(1):119-125
In industrial processing, especially chemical processing, a particular processing point may have a number of outputs, each of which is suitable for directing to another processing point, or to sales. This makes it amenable to analysis via Markov chains. Without recourse to matrix inversion the model enables raw materials and total flows to meet specified sales requirements to be determined. It is particularly suitable for very large industrial complexes, in which the matrix inversion required by the more traditional input-output analysis limits the size of the complex to be so analysed. 相似文献