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排序方式: 共有92条查询结果,搜索用时 234 毫秒
1.
Alexopoulos T Allen C Anderson EW Areti H Banerjee S Beery PD Biswas NN Bujak A Carmony DD Carter T Cole P Choi Y De Bonte RJ Erwin AR Findeisen C Goshaw AT Gutay LJ Hirsch AS Hojvat C Kenney VP Lindsey CS LoSecco JM McMahon T McManus AP Morgan N Nelson KS Oh SH Piekarz J Porile NT Reeves D Scharenberg RP Stampke SR Stringfellow BC Thompson MA Turkot F Walker WD Wang CH Wesson DK 《Physical review letters》1990,64(9):991-994
2.
Lazarus EA Navratil GA Greenfield CM Strait EJ Austin ME Burrell KH Casper TA Baker DR DeBoo JC Doyle EJ Durst R Ferron JR Forest CB Gohil P Groebner RJ Heidbrink WW Hong R Houlberg WA Howald AW Hsieh C Hyatt AW Jackson GL Kim J Lao LL Lasnier CJ Leonard AW Lohr J La Haye RJ Maingi R Miller RL Murakami M Osborne TH Perkins LJ Petty CC Rettig CL Rhodes TL Rice BW Sabbagh SA Schissel DP Scoville JT Snider RT Staebler GM Stallard BW Stambaugh RD St John HE Stockdale RE Taylor PL Thomas DM 《Physical review letters》1996,77(13):2714-2717
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The N-bonded nitrile complexes -[Co(tetren)NCR]3+ (R=Me, Ph, p-MeOC6 H4) have been prepared by the reaction of -[Co(tetren)OH2]3+ with the corresponding nitrile. The kinetics of base hydrolysis have been studied by pH-stat methods. The reactions involve an SN1CB displacement of the nitrile to give the hydroxopentamine; nucleophilic attack at the nitrile carbon to give the corresponding carboxamido complex does not occur. NaN3 reacts with the nitrile complexes in slightly acidic solution (pH ca. 5.7) to give the tetrazolato complexes [Co(tetren)N4 R]2+ (R=Me, Ph) which have been characterised. The reaction of azide ion with -[Co(tetren)NCMe]3+ has been studied kinetically. The reaction is biphasic involving the initial rapid formation of the N1-bonded (5-methyltetrazolato) pentaminecobalt(III) complex with k=2×10–2dm3 mol–1s–1 at 25°C followed by the slow isomerisation to the N2-bonded complex with k=3.5×10–5s–1 at pH 5.7. 相似文献
6.
Allan C. Baxter James H. Cameron Alexander McAuley Fiona M. McLaren John M. Winfield 《Journal of fluorine chemistry》1977,10(4):289-298
Copper(II) fluorine reacts with the pentafluorides, TaF5, PF5, and AsF5, in acetonitrile to give solvated CuII, hexafluoroanion salts. These react with copper metal to give the corresponding CuI compounds. Similar reactions occur between AsF5 and silver(I) or thallium(I) fluorides, but silver(II) fluoride reacts with MeCN, and AgI hexafluoroarsenate is formed. PF5 oxidises Cu slowly in MeCN to give CuI hexafluorophosphate, but AsF5 has no oxidising ability towards metals in MeCN. Spectroscopic data for Cu(MF6)2·5MeCN and Cu(MF6)·4MeCN (M = Ta or P) are discussed. 相似文献
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A comparative evaluation has been made of both proton and (13)C nuclear magnetic resonance techniques in the quantitative characterization of commercial urea-formaldehyde resins. There is good agreement between data derived from (13)C NMR spectra and from (1)H high-field continuous wave, or low-field (Fourier transform) NMR spectra. Low-field continuous wave proton spectra exhibit inferior resolution and provide inaccurate quantitative data. Combination of (13)C and proton NMR with nitrogen analysis gives a quantitative characterization technique for these resins. 相似文献
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The characterisation of two cross-linked poly(acryloylmorpholines), Enzacry Gel K1 and Enzacryl Gel K2, as matrices for aqueous gel permeation chromatography is described. Near ideal plots of logarithm molecular weight versus distribution coefficient, Kd, are obtained for polyethylene glycols and linear, oligomeric α,ω-diols approximate molecular weight (
n) fractionation ranges being 0–4000 and 0–20,000 for Enzacryl Gel K1 and Enzacryl Gel K2, respectively. Anomalous retardation of the Schardinger dextrins, cyclomaltohexose and cyclomaltoheptose, is observed although linear maltosaccharides behave normally. The internal gel volumes, calculated from column elution data in water, are significantly larger than the volumes of solvent imbibed by the dry column packings on constituting the gel. Internal gel volumes and solvent imbibition volumes in water are compared with the corresponding values obtained in chloroform and tetrahydrofuran. The two parameters are discussed, in the case of Enzacryl Gel K2 in water and chloroform, in the light of plots of logarithm viscometric hydrodynamic volume versus Kd for polyethylene glycols. 相似文献
9.
Rachel M. McLaren Denise Haunani Solomon Jennifer S. Priem 《The Journal of communication》2012,62(6):950-971
This study expands the relational turbulence model (RTM; Solomon & Knobloch,) by theorizing about how characteristics of relationships and relational judgments influence people's experiences of hurtful messages. Previous applications of RTM to hurt have uncovered associations among relational characteristics that influence people's hurtful experiences; however, the process by which these characteristics influence experiences of hurt remains unclear. We propose that relational communication (specifically, perceptions of dominance, and disaffiliation) is the mechanism linking relational qualities to hurt. A multigroup SEM was conducted to test for the possibility of sex differences. Results showed that people's experiences of hurt vary as a function of both relationship characteristics and relational inferences. Results also indicated a difference in path coefficients for males and females. 相似文献
10.
Jose Castro‐Perez Nathan Hatcher Nana Kofi Karikari Sheng‐Ping Wang Vivienne Mendoza Henry Shion Alan Millar John Shockcor Mark Towers David McLaren Vinit Shah Stephen Previs Karen Akinsanya Michele Cleary Thomas P. Roddy Douglas G. Johns 《Rapid communications in mass spectrometry : RCM》2014,28(22):2471-2479