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101.
A modification of a relatively new technique (thermal and mass chromatography) is used to study the volatile products evolved in the thermal oxidative degradation of isotactic poly(1-pentene) at 115° C under 100% oxygen. This new technique allows certain data to be obtained much more easily and more reliably than before. 相似文献
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Let μ be the measure onI′ (? d ) corresponding to the Gaussian process with mean zero and covariance (f,(?Δ+1)?1 g) onI (? d ). It is proven that the set $$( - \Delta _{d - 1} + 1)^{d/4 - \tfrac{1}{2} + \alpha } (1 + x^2 )^{d/4} [\log (2 + x^2 )]^\beta L^2 (\mathbb{R}^d )$$ has μ measure one if α>0 and β>1/2 and μ measure zero if α>0 and β<1/2; here Δ d?1 is the Laplacian in anyd?1 dimensions whend>1 and Δ0=Δ. 相似文献
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108.
The spectra of certain deuteriated binuclear chromium complexes have been obtained which help to elucidate some of the fragmentation processes of the molecular ion. The effect of the relative strengths of the metal-ligand and metal nitrosyl bonds is also discussed. 相似文献
109.
M. G. Bite S. Berezenko F. J. S. Reed L. Derry 《Applied biochemistry and biotechnology》1988,18(1):275-284
Incompressible Macrosorb composite adsorbents, while retaining all the desirable properties of traditional agarose-based hydrogel media, overcome the operational limitations imposed by the use of soft hydrogels: They permit useful application of fast flow rates without restrictions on bed depth and they can be used in fluidized bed mode. Considerations which are important when contemplating scaled-up processing are discussed. A comparative cost estimate for a production process for extracting albumin from bovine serum in column equipment illustrates the various advantages which may be exploited when using a composite adsorbent in place of a conventional soft gel equivalent. 相似文献
110.
The adsorption of oxygen and the interaction of carbon monoxide with oxygen on Ru(101) have been studied by LEED, Auger spectroscopy and thermal desorption. Oxygen chemisorbs at 300 K via a precursor state and with an initial sticking probability of ~0.004, the enthalpy of adsorption being ~300 kJ mol?1. As coverage increases a well ordered ¦11,30¦ phase is formed which at higher coverages undergoes compression along [010] to form a ¦21,50¦ structure, and the surface eventually saturates at 0 ~ . Incorporation of oxygen into the subsurface region of the crystal leads to drastic changes in the surface chemistry of CO. A new high; temperature peak (γ CO, Ed ~ 800 kJ mol?1) appears in the desorption spectra, in addition to the α and β CO peaks which are characteristic of the clean surface. Coadsorption experiments using 18O2 indicate that γ CO is not dissociatively adsorbed, and this species is also shown to be in competition with β CO for a common adsorption site. The unusual temperature dependence of the LEED intensities of the ¦11,30¦-O phase and the nature of α, β, and β CO are discussed. Oxygen does not displace adsorbed CO at 300 K and the converse is also true, neither do any Eley-Rideal or Langmuir-Hinshelwood reactions occur under these conditions. Such processes do occur at higher temperatures, and in particular the reaction CO(g) + O(a) → CO2(g) appears to occur with much greater collisional efficiency than on Ru(001). The oxidation of CO has been examined under steady state conditions, and the reaction was found to proceed with an apparent activation energy of 39 kJ mol?. This result rules out the commonly accepted explanation that CO desorption is rate determining, and is compared with the findings of other authors. 相似文献