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Preparation of trans-[Pt(ox)2X2]2? (X = Cl, Br, I, SCN, OH) by Oxidative Addition to [Pt(ox)2]2? in Organic Solvents After extraction of [Pt(ox)2]2? with long-chain alkyl-ammonium ions into organic solvents the new PtIV complexes trans-[Pt(ox)2X2]2?, X = Cl, Br, I, SCN, OH, are formed directly by oxidative addition. In nonpolar solvents the bulky organic cations prevent the formation of compounds with columnar structure which by partial oxidation in aqueous solution are formed immediately. The IR and Ra spectra of the stable anhydrous (TBA) salts are assigned according to point group D2h. A characteristical dependence of the C?O, C? O, and Pt? O stretching modes in response to the oxidation state of the central ion is observed. There is vibrational fine structure in the absorption spectrum of [Pt(ox)2]2? measured at 10 K with long progressions by coupling of d—d transitions with vs(Pt? O) and vs(C?O). The characteristical feature in the UV/VIS spectra of the PtIV complexes is caused by intensive π(O, X) ← eg(Pt) CT transitions. 相似文献
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de Boer J Leonards PE Klungsøyr J McHugh B Nixon E McGovern E Rimkus GG 《Journal of AOAC International》2003,86(2):432-438
A comparison was made between electron capture negative ionization quadrupole mass spectrometry (ECNI-MS) and electron capture detection (ECD) with regard to repeatability and reproducibility for the gas chromatographic (GC) analysis of toxaphene congeners [chlorobornanes (CHBs)]. The tests, including standard solutions and several cleaned fish extracts, showed larger relative standard deviations (RSDs) for the repeatability of ECNI-MS but no differences in the reproducibility of the 2 techniques. The sensitivity of the GC-ECNI-MS was considerably better than that of GC/ECD. Four stepwise-designed comparative tests were also conducted on GC analysis, cleanup, and the complete method. The results showed that, according to the current state-of-the-art, coefficients of variation for the between-laboratory performance were not < 20% and were usually between 20 and 30%. In spite of separation problems, e.g., for CHB 26, which cannot be separated into a single-component peak, a 95% methyl 5% phenyl polysiloxane (CP Sil 8) column was preferred to more polar columns for the analysis of CHBs 26, 40, 41, 44, 50, and 62. CHB 62 was more difficult to determine than CHB 26 and 50. Addition of the CHBs 40, 41, and 44 to the standard set of 3 chlorobornanes (26, 50, and 62) resulted in more separation problems. A 3-step cleanup method was recommended. 相似文献
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The enantioselective conjugate addition of diethylzinc to the activated nitroolefin methyl 3-nitropropenoate is efficiently catalyzed by copper(I) complexes with BINOL-based enantiopure phosphoramidite ligands. The nitroolefin moiety acts as the predominant Michael acceptor, giving rise to the unambiguous formation of 2-alkyl-3-nitro-propanoates. Moderate to excellent enantioselectivities and high chemical yields are obtained. The product can easily be transformed into a beta(2)-homoamino acid. [reaction--see text] 相似文献
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R. Brandelik W. Braunschweig K. Gather V. Kadansky K. Lübelsmeyer P. Mättig H.-U. Martyn G. Peise J. Rimkus H.G. Sander D. Schmitz A. Schultz von Dratzig D. Trines W. Wallraff H. Boerner H.M. Fischer H. Hartmann G. Zobernig 《Physics letters. [Part B]》1980,94(1):91-95
Inclusive K0-production has been measured in e+e- annihilation at a center of mass energy of about W = 30 GeV. The ratio of K0 + K0 production to μ+μ- production is RK0 = 5.6 ± 1.1 (statist. error) ± 0.8 (system.error) This value is about a factor of three higher than RK0 at W = 7 GeV. The cross sections (s/β) dσ/dx is consistent with a scaling behaviour. 相似文献
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R. Brandelik W. Braunschweig K. Gather F.J. Kirschfink K. Lübelsmeyer H.-U. Martyn G. Peise J. Rimkus H.G. Sander D. Schmitz A.Schultz von Dratzig D. Trines W. Wallraff H. Boerner H.M. Fischer H. Hartmann E. Hilger G. Zobernig 《Physics letters. [Part B]》1981,105(1):75-80
Performing a PWA of the π?π?π+ system over the ?tp/p range 0.2 to 0.4 GeV2 we find evidence for a JP = 0? ,JG=1? meson of mass 1342 ± 20 MeV and width 220 ±70 MeV decaying into ?π. This state is produced by natural parity exchange with a slope similar to that of elastic scattering. It can be interpreted as a radial excitation of the π meson (π′). 相似文献
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R. Brandelik W. Braunschweig K. Gather F.J. Kirschfink K. Lübelsmeyer H.-U. Martyn G. Peise J. Rimkus H.G. Sander D. Schmitz D. Trines W. Wallraff H. Boerner H.M. Fischer H. Hartmann E. Hilger W. Hillen G. Knop G. Zobernig 《Physics letters. [Part B]》1982,113(6):499-508
The ration R = σ(e+e? → hadrons)σμμ was measured between 12.0 and 36.7 GeV c.m. energy W with a precision of typically ± 5.2%. R is found to be constant with an average R = 4.01 ± 0.03 (stat) ± (syst.) for W ? 14 GeV. Quarks are found to be point-like, the mass parameter describing a possible quark form-factor being larger than 186 GeV. Fits including QCD corrections and a weak neutral-current contribution are presented. 相似文献
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In this study,the three dimensional nanoscale organization in the photoactive layers of poly(3-hexylthiophene) (P3HT) and a methanofullerene derivative (PCBM) is revealed by transmission electron tomography.After annealing treatment,either at elevated temperature or during slow solvent evaporation,nanoscale interpenetrating networks are formed with high crystalline order and favorable concentration gradients of both components through the thickness of the photoactive layer.Such a tailored morphology acco... 相似文献
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