My late colleague and friend Alfred Kahn relayed how President Jimmy Carter hired him in 1977 to head the Civil Aeronautics Board to reform and ultimately deregulate the US airline industry. Accepting the job, he told a group of airline executives (to their fury), “I really don't know one plane from the other. To me they are all marginal costs with wings.” He used that term to signal his intention of reforming the industry in keeping with economic principles, uninfluenced by the romance of air travel. 相似文献
Iodoperfluooralkylation of terminal alkenes and alkynes is effectively photo‐promoted by benzophenone 2 (BP) or the photoreducible copper(II) complex 1 . In particular, BP at 1 mol% in methanol upon 365 nm irradiation with a low‐pressure mercury lamp (type TLC=thin layer chromatography, 6 W) results in a fast reaction with excellent reaction yields. Complex 1 and BP 2 exhibited very similar reactivity, suggesting that the reactions involving 1 are likely to be governed by the benzophenone photoactivation processes, rather than copper(I)/(II) redox processes. Mechanistic investigations using transient absorption spectroscopy revealed that a deactivation pathway of the benzophenone triplet (3BP*) is via its reaction with the methanol solvent. We propose that the generated radicals, in particular .CH2OH, play a key role in the initiation step forming Rf. by reacting with RfI, Rf. then entering a radical chain cycle. 1H NMR studies provided evidence that a substantial amount (∼7% NMR yield) of the hemiacetal CH3OCH2OH is formed, i.e., the possible by‐product of the reaction between .CH2OH and RfI. Finally, DFT calculations indicate that a triplet‐triplet energy transfer (TTET) process from 3BP* to perfluorooctyl iodide (C8F17I) is unlikely or should be rather slow under the reaction conditions, consistent with the transient absorption studies.
Journal of Inorganic and Organometallic Polymers and Materials - In recent decades, the analysis of nanoparticles is of greater importance for their applications in various fields. This present... 相似文献
Soil Mechanics and Foundation Engineering - The resilience of the Daikai subway station during the Kobe earthquake is taken as a case study of tunnel endurance at various points under different... 相似文献
Metal Science and Heat Treatment - Scanning electron microscopy and confocal laser scanning microscopy are used to study a fracture surface of hydrogen-charged low-carbon steel, which has been... 相似文献
Metal Science and Heat Treatment - Ti – Zr-based alloys with a high zirconium content prepared by vacuum-arc remelting with nonconsumable tungsten electrode are studied. The optimum number of... 相似文献
A comparative study of propylene polymerization in liquid monomer is performed under laboratory conditions using the IK-8-21 Ti-Mg catalyst designed at the Boreskov Institute of Catalysis and imported industrial catalysts (conditionally labeled TMC-1, -2, and -3). The activity and stereospecificity of the catalysts are estimated along with properties of the resulting polypropylene (granular composition and physicomechanical characteristics). It is shown that the IK-8-21 catalyst is not inferior to imported counterparts in terms of catalytic properties in the synthesis of polypropylene. The polypropylene powder formed on IK-8-21 is homogeneous and has good morphology. The physicomechanical characteristics of polypropylene synthesized on the domestic IK-8-21 catalyst are similar to those for polypropylene prepared with the imported TMK-1 catalyst. 相似文献
JOM - The use of titanium machine turnings has been identified as a possible ultralow-cost method to produce titanium powder. However, very little data are available on the viability of this... 相似文献
Protection of Metals and Physical Chemistry of Surfaces - The methods of describing absolute adsorption isotherms of binary nonelectrolyte solutions components on macro- and microporous adsorbents... 相似文献