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991.
Uwe Dieckbreder Gerd‐Volker Rschenthaler Alexander A. Kolomeitsev 《Heteroatom Chemistry》2002,13(7):650-653
Bis(trifluoromethyl)phosphines RP(CF3)2 (R = Me, NEt2) were methylated by MeOSO2CF3, yielding the respective phosphonium salts [RP(CF3)2Me]+ and CF3SO3−. Deprotonation using MeNP(NEt2)3 led to the phosphorus ylides RP(CF3)2CH2, stable in solution at ambient temperature, which could be converted into 1,2λ5σ5‐oxaphosphetanes by adding hexafluoroacetone. © 2002 Wiley Periodicals, Inc. Heteroatom Chem 13:650–653, 2002; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/hc.10061 相似文献
992.
Gerd Schfer Wilder Carrillo‐Cabrera Walter Schnelle Horst Borrmann Rüdiger Kniep 《无机化学与普通化学杂志》2002,628(1):289-294
A borophosphate hydrate with general composition {(NH4)xCo((3–x)/2)}(H2O)2[BP2O8] · (1 – x) H2O (x ≈ 0.5) was prepared under mild hydrothermal conditions (T = 170 °C). The crystal structure of the purple title compound was refined in space group P65 (no. 170) as a merohedric twin (a = 949.14 pm, c = 1558.25 pm, R1 = 0.037, wR2 = 0.092 for all data). According to preliminary X‐ray investigations, vis‐spectra, and magnetic susceptibility measurements, a second blue coloured variant exhibits a superstructure of the title compound with a change in coordination numbers around cobalt from six and five to six and four. Both phases show reversible de‐/rehydration properties. 相似文献
993.
Reactions of PtCl2(cod) (cod = cycloocta‐1,5‐diene) with 2,4,6‐trifluoro‐ and 2,3,4,5‐tetrafluoro‐phenyllithium in diethyl ether gives Pt(C6H2F3‐2,4,6)2(cod) ( 1 ) (monoclinic, P21/n, Z = 4, a = 7.141(1), b = 15.002(2), c = 17.071(3) Å, β = 91.37(2)°) and Pt(C6HF4‐2,3,4,5)2(cod) ( 2 ) (triclinic, P 1, Z = 2, a = 10.150(2), b = 10.762(2), c = 10.812(2) Å, α = 63.606(3), β = 63.327(3), γ = 76.496(3)°) respectively, which have two ipso carbon atoms and two double bond midpoint centres in a square planar arrangement, and aromatic rings angled near perpendicular to the coordination plane. 相似文献
994.
A New Chloropalladate(II): BaPdCl4 BaPdCl4 was prepared through reaction of barium chloride and palladium dichloride (molar ratio 2:1) with the aid of the Bridgman technique. According to a X‐ray single crystal investigation, BaPdCl4 crystallizes with the orthorhombic crystal system (space group Pbcn (No. 60), Z = 4, a = 686.7(1), b = 1258.8(2) pm, c = 750.2(2), Rall = 0.0383). The crystal structure is built up from square planar [PdCl4] units which are linked together by Ba2+ ions in an eightfold coordination. 相似文献
995.
[Ag(NH3)2]ClO4: Crystal Structures, Phase Transition, and Vibrational Spectra [Ag(NH3)2](ClO4) is obtained from a solution of AgClO4 in conc. ammonia as colourless single crystals (orthorhombic, Pnmn, Z = 4, a = 795.2(1) pm, b = 617.7(1) pm, c = 1298.2(2) pm, Rall = 0.0494). The structure consists of linearly coordinated cations, [Ag(NH3)2]+, stacked in a staggered conformation and of tetrahedral (ClO4)‐ anions. A first order phase transition was observed between 210 and 200 K and the crystal structure of the low‐temperature modification (monoclinic, P2/m, Z = 4, a = 789.9(5) pm, b = 604.1(5) pm, c = 1290.4(5) pm, β = 97.436(5)°, at 170 K, Rall = 0.0636) has also been solved. Spectroscopic investigations (IR/Raman) have been carried out and the assignment of the spectra is discussed. 相似文献
996.
Gerd Rosenkranz 《PAMM》2007,7(1):1080301-1080302
Laboratory data from clinical trials are considered precursors of potential organ dysfunctions. The routine analysis of these data focusses on the occurrence of extremely high or low values relative to normal ranges, the change of these incidences compared to baseline, or the worst values from each individual patient. However, only rarely is an attempt made to model the dynamics of the measurements over time. In this paper we propose to model laboratory measurements by stochastic processes, specifically by Ornstein-Uhlenbeck processes. The aim is to estimate parameters of these processes in order to characterize a potential effect of drugs or other medical treatments. (© 2008 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
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