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41.
Kenneth R. Seddon 《Journal of organometallic chemistry》1985,282(2):c47-c50
Rhodium hydrides have been observed in solution in the reaction of cationic rhodium(I) complexes of bis(tertiary phosphines) with hydrogen. 相似文献
42.
KennethR. Seddon 《Trends in analytical chemistry : TRAC》1986,5(10):XXIII
43.
44.
Paradigm confirmed: the first use of ionic liquids to dramatically influence the outcome of chemical reactions 总被引:3,自引:0,他引:3
It has been an unproven paradigm that the choice of which ionic liquid to use in a chemical reaction can have a dramatic effect on the outcome of that chemical reaction. We demonstrate, for the first time, that the reaction of toluene and nitric acid in three different ionic liquids gives rise to three completely different products in high yield. Furthermore, ionic liquids can catalyze these reactions with the only byproduct being water. [reaction: see text] 相似文献
45.
Elaine A. Seddon 《Journal of organometallic chemistry》1984,270(1):c29-C32
An X-ray analysis of [Os(CO)4AuPPh32] shows that the metal atoms define an isosceles triangle in which the Au-Au distance is 2.929(1) Å, which is ca. 0.1 Å shorter than in the corresponding iron analogue [Fe(CO)4AuPPh32]. 相似文献
46.
ORMOSILs have been prepared in the series TMOSx·MTMS(100 – x) (where TMOS is tetramethoxysilane; MTMS is methyltrimethoxysilane; x is mol% silane with respect to total silane for 0 x 100) by means of acid catalyzed, sol-gel processing. After drying at 60°C, small bulk samples were obtained of excellent optical clarity. Powder X-ray diffraction (XRD) patterns, in the range of 5 to 60°2, were compared with that of fused silica. All the prepared samples were amorphous. Fused silica exhibits one broad peak, d2 centered at d-spacing 4.12 Å. For the TMOS100 silica xerogel, the analogous broad peak had shifted slightly, to be centered at 3.88 Å; and remained in about the same position as x was decreased for the series TMOSx·MTMS(100 – x). In addition, a second, broad peak, d1, was observed for the ORMOSIL series centered at the d-spacing 8.7 Å for MTMS100 (i.e., x = 0) and increasing smoothly as x was increased, reaching 11.3 Å for x = 70, and >11.3 Å for x > 70. The intensity of d1 was found to have trebled, relative to the intensity of d2, on increasing the organic character of the matrix from TMOS70·MTMS30 to MTMS100.The d2 peak appearing at about 4 Å for both fused silica and the ORMOSILs is assumed to be associated with the spacing between silicon atoms connected by means of an oxygen bridge. The Si–O–Si angle for silica xerogels is known to depend upon the nature of the sol-gel processing and is bigger than that of fused silica.The d1 peak may be associated with the spacing between silicons attached to methyl groups and indicative of channels of methyl groups in the structure. Alternatively, the d1 peak may have its origin in a preferred, discrete structural unit in the matrix for instance cubane based on a octameric silicon arrangement. 相似文献
47.
48.
Class II ormosils in the systems: methyl, propyl, vinyl and phenyl silicates have been structurally investigated for their
suitability as photonic materials and this paper is a precis of many data. From visible and near-infrared spectroscopy these
ormosils have: (i) intrinsic optical windows in the visible and at 1.06, 1.3 and 1.55 μm and (ii) low residual water, despite
being synthesised at only 60°C. The residual water can be expelled under vacuum. Solid state29Si nuclear magnetic resonance spectroscopy shows that matrix condensation increases as the organic content of the matrix is
increased; this is accompanied by a decrease in BET surface area. 相似文献
49.
Franca Bigi H.Q. Nimal Gunaratne Carla Quarantelli Kenneth R. Seddon 《Comptes Rendus Chimie》2011,14(7-8):685-687
A new class of catalytic ionic liquids, containing chiral tungstate(VI) anions, gives enantiomeric excesses up to 96% for sulfide oxidation to sulfoxides. 相似文献
50.
Özge Pala Dirk J Vriens Jac AM Vennix 《The Journal of the Operational Research Society》2015,66(4):593-601
Escalation of commitment, the tendency of decision makers to keep on investing in losing courses of action, has been shown to be a costly decision bias that affects many areas of decision making. Even though escalation is a widely studied phenomenon, there has been comparatively little research on how to avoid this bias. The present study focuses on de-escalation of commitment and proposes that causal loop diagrams (CLDs) can help to decrease escalating commitment to a failing course of action. By means of an experiment, this study shows that using a CLD decreases escalation tendencies. 相似文献