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排序方式: 共有1006条查询结果,搜索用时 15 毫秒
1.
2.
The degradation of acenaphthylene, acenaphthene, 2-methylnaphthalene, 2-methylindene, 3-methylindene and indene in water solutions was studied. These compounds at the 25-150 mug/l. level were almost totally degraded at ambient temperature within three days. The microbial population responsible for the degradation occurs naturally in ground-water taken from an aquifer in Ames, Iowa, which is contaminated with coal-tar products. These unidentified micro-organisms adapt readily to other waters when used as an inoculant for the degradation of aromatic compounds. The preservation of water to prevent such degradation was also investigated. Filtration through a 0.45-mum filter was found the most effective procedure for preserving the hydrocarbons in these waters. 相似文献
3.
M. A. Baldwin A. G. Loudon R. E. Dunmur R. Schmutzler I. K. Gregor 《Journal of mass spectrometry : JMS》1977,12(5):275-278
The ionization potentials of a series of N-methyl,N′-R-1,2,4-phosphadiazetidine-3-ones and related compounds have been determined. The nature of the highest occupied orbital of the molecules and the use of empirical rules to rationalize the variations in the ionization potentials are discussed. The changes in the fragmentation patterns are related to the different low ionization potential site(s) in each molecule. The occurrence of various rearrangement ions are discussed on a similar basis. 相似文献
4.
A robust, easy to optimize, and efficient homonuclear correlation NMR experiment for half-integer quadrupolar nuclei in solids is described and has been experimentally tested on anhydrous Na2HPO4-(23Na, S= 3/2 nucleus) and as-synthesized AlPO4-14 (27Al, S= 5/2 nucleus), an aluminophosphate molecular sieve. 相似文献
5.
M. Eddaoudi A. W. Coleman P. C. Junk 《Journal of inclusion phenomena and macrocyclic chemistry》1996,26(1-3):133-151
The solubilities of -, -, and -cyclodextrin have been measured in the presence of the first row transition metals: Cr3+, Mn2+, Fe3+, Co2+, Ni2+, Cu2+ and Zn2+; chlorides, nitrates and sulphates (in this case Fe2+), and, for companson, with CaCl2, the corresponding Group IIa salt. Where possible the measurements are reported as a function of the activity of the salts. In general, for the transition metals the sulphates all show a linear decrease in solubility with increasing salt activity: for the nitrates the solubility increases and then reaches a limiting value; and for the chlorides a small decrease in solubility is observed at low activity followed by an increase in solubility at higher salt activity. Circular dichroism measurements confirm that there is no direct complexation at non-basic pH.Presented at the Sixth International Seminar on Inclusion Compounds, Istanbul, Turkey, 27–31 August 1995. 相似文献
6.
Azomethine ylide 3 , generated by thermolysis of 3,4-diphenyl-Δ1-1,2,3-triazoline-5,5-dimethyldicarboxylate 1 , can be trapped by isonitriles to give 3-imino-1,4-diphenylazetidine-2,2-dimethyldicarboxylates 5 . The IR, 1H-NMR, 13C-NMR and mass spectral data of the new compounds are discussed. 相似文献
7.
Alexander Goerke Gregor Leipelt Hartmut Palm C. P. Schulz I. V. Hertel 《Zeitschrift für Physik D Atoms, Molecules and Clusters》1995,32(4):311-320
The first reactive differential scattering study for atomic clusters is reported. Oxidation of Na
x
(x8) with O2 is investigated in a crossed beam apparatus. Sodium oxide (Na
n
O,n4) and sodium dioxide (Na
n
O2,n6) are produced with a total reactive cross section from 50 to 80 Å2, depending on the cluster size. The excess energies for these reactions are estimated by an SCF type ab initio calculation and range from 0.5 to 5 eV. The large cross section may then be understood quantitatively in terms of a harpooning mechanism as a first step in the reaction path. Angular distributions have been determined for the most abundant products, showing strong forward scattering. Two different schemes are discussed for the reaction: while the dioxides Na
n
O2 may be formed by an evaporative cooling process from a highly excited collision complex, formation of Na
n
O appears to originate from a direct process. In both cases the experimental data suggest that most of the exothermicity remains in the reaction products. 相似文献
8.
Mitsuzo Shida Harry P. Gregor 《Journal of polymer science. Part A, Polymer chemistry》1966,4(5):1113-1119
The swelling characteristics of an oleophilic anion-exchange resin in methanol–benzene and ethanol–chloroform mixed solvent systems were compared with those of a conventional anion-exchange resin. The oleophilic resin was prepared by amination of chloromethylated polystyrene 1% DVB with N,N-dimethyldodecylamine. It showed a large shift of the swelling peak from polar to less polar solution compositions in both methanol–benzene and ethanol–chloroform systems as compared with the swelling of conventional resins. Total solvent uptake and solvent distribution between resin and solvent phases were also determined. The less polar solvent (benzene or chloroform) was sorbed preferentially by the oleophilic resin over a wide range of composition, while preference for the more polar solvent (methanol or ethanol) by the conventional resin was shown over the entire composition of the mixed solvent systems. The Newman-Krigbaum treatment of mixed solvents was applied to swelling data on the ethanol–chloroform–oleophilic resin system, where the volume of the gel network plus the solvent imbibed was relatively constant over the entire range of composition. The result suggests a strong similarity of the liquid–liquid interaction terms in this gel phase compared with those in the pure binary liquid phase. 相似文献
9.
10.