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11.
R. P. Hallett K. G. McKay S. P. Balm A. W. Allaf H. W. Kroto A. J. Stace 《Zeitschrift für Physik D Atoms, Molecules and Clusters》1995,34(1):65-70
Reaction studies of carbon clustersC
n
in the rangen=8–37, produced by laser vaporisation in a supersonic nozzle, have been investigated using time-of-flight mass spectrometry. Clear differences in reaction products formed on hydrogenation are detected which show that even and odd clusters behave quite differently and furthermore thatat least two different types of even cluster appear to exist. The reactivity patterns for clusters C
n
withn=16, 18 and 22 are in a different class from those withn=20, 24, 26 ..., a behaviour consistent with the existence of closed cage fullerene structures for even clusters with 20 or more carbon atoms (other thann=22). 相似文献
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Gordon McKay Stephen J. Allen Ian F. McConvey Michael S. Otterburn 《Journal of colloid and interface science》1981,80(2):323-339
A three-step model has been proposed for the adsorption of Astrazone Blue dye (Basic Blue 69) on peat. The initial rate of uptake of dye ions due to physical adsorption and chemisorption (ion exchange) has been correlated using a surface mass transfer coefficient. These coefficients have been determined and expressed in the dimensionless mass transfer form, Sh/Sc0.33, as a function of agitation, initial dye concentration, peat particle size range, dye solution temperature, and mass of peat. 相似文献
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Modification of commercial LC/MS instrumentation to allow both atmospheric pressure (AP) LC/MS and GC/MS is described. Advantages of this additional capability versus LC/MS alone include higher chromatographic resolution in the GC versus LC mode, greater peak capacity for complex mixture analysis, higher sensitivity for a variety of volatile compounds, and the ability to observe compounds of low polarity that are not readily observed in LC/MS. Advantages over conventional GC/MS include the ability to use higher carrier gas flow and shorter columns for passing less volatile materials through the gas chromatograph, selective ionization, and rapid switching between positive and negative ion modes. Other advantages include application of the enhanced capabilities of LC/MS instrumentation to GC/MS analyses such as cone voltage fragmentation, MS(n), high mass resolution, and accurate mass measurement. Limitations of APGC/MS include the inability to observe saturated hydrocarbon and certain other highly nonpolar compounds and less odd-electron fragmentation for computer aided library searching. For some analyses, the limitation related to ionization of highly nonpolar compounds is advantageous, as is the simplified mass spectrum and easy molecular weight identification that results from less fragmentation observed in the AP ionization mode. 相似文献
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C. Yonezawa H. Matsue K. McKay P. Povinec 《Journal of Radioanalytical and Nuclear Chemistry》2001,248(3):719-725
Multi-element and isotopic analyses of oils and marine environmental samples were carried out to estimate a contamination source using a "finger printing" method. Elemental analyses were carried out using neutron-induced prompt gamma-ray analysis (PGA), instrumental neutron activation analysis (INAA) at the Japan Atomic Energy Research Institute, Tokai-mura, Japan (JAERI) and ICP-MS in the IAEA Marine Environment Laboratory, Monaco (MEL). Fifteen elements including light elements, H, B, N, Si and Ca, which cannot be determined by INAA and ICP-MS, were determined by PGA. A total of 47 elements were determined in the present study. The potential of PGA for the determination of isotopic ratios was tested by measuring 34S/32S ratios in oils. The evaluation of historical records of marine environmental conditions using annual bands in coral samples was also investigated. 相似文献
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Prem Paul Singh Jan Spitzer Robert M. McKay Keith G. McCurdy Loren G. Hepler 《Thermochimica Acta》1978,24(1):111-115
We have made calorimetric and density measurements leading to apparent molar heat capacities and volumes of dilute aqueous solutions of silver nitrate and silver perchlorate at 298 K. Resulting apparent molar properties at infinite dilution are the following: φoc(AgNO3) = ? 36.8 J K?1 mol?1, φov(AgNO3) = 29.1 cm3 mol?1, φoc(AgClO4) = 11.0 J K?1 mol?1, and φov(AgClO4) = 43.5 cm3 mol?1. 相似文献