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941.
942.
本文介绍了一种分析裂化气中杂质烃的方法。所建分析系统由填充玻璃毛细管柱和填充预柱各一根、阀和FID各一个组成。采用一次进样、外标法定量,约30分钟即可完成测定裂化气中低至0.5ppm含量的痕量C_2~C_4炔和二烯。方法适用围范至少是0.5ppm~1%。当样品含量为1~5 ppm时,相对标准偏差小于50%。 相似文献
943.
Polynuclear Complexes with Fe? As, Fe? Sb, and Fe? Bi Frameworks The anionic iron clusters Fe3(CO)112? and Fe4(CO)132? were reacted with compounds EX3 and with organic derivatives REX2 and R2EX of the elements arsenic, antimony, and bismuth. Commonly redox and cluster degradation reactions were observed. The new complexes [(CO)4Fe? AsMe2? Fe(CO)4]?, [HFe3(CO)9(mu;3-SbBut)]?, [Fe3(CO)10 (mu;3-Sb)]?, and [Fe3(CO)10(mu;3-Bi)]? were formed and isolated as their PPN salts. The Fe? As? Fe complex was identified by a structure determination, the other complexes were identified by their spectra. 相似文献
944.
J. Howard Rytting Danny R. McHan Takeru Higuchi David J. W. Grant 《Journal of solution chemistry》1986,15(8):693-703
Henry's law constants have been determined for -butyrolactone (BL), ethyl acetate (EA), and 2-methyl-3-pentanol (MEP) in mixtures of iso-octane (ISO) and toluene (TOL), for BL, EA, TOL, and ISO in cinnamaldehyde (CIN) and for TOL and ISO in each other and in BL. From these data and published vapor pressures, the activity coefficients at infinite dilution and the standard molar Gibbs free energy of transfer, G
2
0
of the solutes from dilute solution in ISO to dilute solution in each solvent medium have been calculated. The different behavior patterns of BL and EA are attributed to differences in their abilities to exist in different conformations possessing different dipole moments. For polar solutes, G
2
0
decreases with increasing polarizability of the solvent and with increasing dipole moment of the solute, suggesting increased contributions from dipole-induced dipole (Debye) interactions. The sigmoidal plot of G
2
0
against the change in pair potential energy calculated from the classical expressions suggests that G
2
0
seriously underestimates the strength of the Debye interactions in comparison with the London interactions. 相似文献
945.
Th. Ramdahl J. Arey B. Zielinska R. Atkinson A. M. Winer 《Journal of separation science》1986,9(9):515-517
This paper reports the retention indices of eighteen of the possible twenty-five dinitrofluoranthene isomers. 相似文献
946.
The rate of the Wolff-Kishner reaction of benzophenone hydrazone in butyl carbitol increases as the cation of the alkoxide base is varied in the order K>Na>Li>Mg. The replacement of butyl carbitol by 1-decanol also accelerates the reaction, and an additional increase is caused by the presence of crown ether. On the basis of changes in the activation parameters, it is concluded that the reactivity of the hydrazone anion increases as the contact ion pair becomes more fully solvated and dissociated. 相似文献
947.
948.
949.
SynthesesandCharacterizationsof(η~5-C_5H_5)MoFeCo(CO)_8(μ_3-S)and(η~5-C_5H_5)_2Mo_2Fe(CO)_7(μ_3-S):X-rayCrystalStructureof(η~5-C_5H_... 相似文献
950.