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91.
92.
Two of the stable selenenic acids reported in the literature are actually other materials. 相似文献
93.
J.H. Cobb S. Iwata R.B. Palmer D.C. Rahm I. Stumer C.W. Fabjan I. Mannelli K. Nakamura A. Nappi W. Struczinski W.J. Willis M. Goldberg N. Horwitz G.C. Moneti C. Kourkoumelis A.J. Lankford P. Rehak 《Physics letters. [Part B]》1977,68(1):101-104
The cross-section for J/ψ production in proton-proton collisions has been measured as a function of centre-of-mass energy at the CERN Intersecting Storage Rings by observing its decay into electron-positron pairs. This cross-section is found to rise by a factor of about six over the full centre-of-mass energy range from √s=23 to √s=63 GeV. Electrons resulting from this decay were identified by the use of liquid argon calorimeters and lithium foil transition radiators. Measurements of the energies of the electrons were obtained from the liquid argon calorimeters. 相似文献
94.
D. J. Cutler M. Glotin P. J. Hendra H. Jobic K. Holland Moritz M. E. A. Cudby H. A. Willis 《Journal of Polymer Science.Polymer Physics》1979,17(6):907-915
Raman spectroscopy, x-ray diffraction, and thermal analysis are used to investigate the structure of linear high-density polyethylene rapidly quenched from the melt to cryogenic temperatures. All the results point to the production of a glassy phase which crystallizes when heated above 170 K. 相似文献
95.
The Coriolis resonance between ν4 and ν7 in CH3CN and between ν1 and ν5, ν3 and ν6, and ν4 and ν7 in CD3CN has been analyzed, applying the technique developed by DiLauro and Mills, to obtain the signs of [] and the ratio of to for the interacting pairs in CD3CN. For (ν4, ν7) in both CH3CN and CD3CN, the sign of [] is found to be negative as it is also for (ν1, ν5) in CD3CN. For (ν3, ν6) the sign of this interaction term is found to be positive. For a given definition of normal coordinates the signs of these interaction terms give the relative signs of and ; our study also gives approximate values for the corresponding ratio [] 相似文献
96.
A number of trifluoroacetates, mesylates, and triflates have been studied in ionic liquids. Several lines of evidence indicate that all of these substrates react via ionization to give carbocationic intermediates. For example, cumyl trifluoroacetates give mainly the elimination products, but the Hammett rho+ value of -3.74 is consistent with a carbocationic process. The analogous exo-2-phenyl-endo-3-deutero-endo-bicyclo[2.2.1]hept-2-yl trifluoroacetate gives an elimination where loss of the exo-hydrogen occurs from a cationic intermediate. 1-Adamantyl mesylate and 2-adamantyl triflate react to give simple substitution products derived from capture of 1- and 2-adamantyl carbocations by the residual water in the ionic liquid. The triflate derivative of pivaloin, trans-2-phenylcyclopropylcarbinyl mesylate, 2,2-dimethoxycyclobutyl triflate, the mesylate derivative of diethyl (phenylhydroxymethyl)-thiophosphonate, and Z-1-phenyl-5-trimethylsilyl-3-penten-1-yl trifluoroacetate all give products derived carbocation rearrangements (kDelta processes). anti-7-Norbornenyl mesylate gives products with complete retention of configuration, indicative of involvement of the delocalized 7-norbornenyl cation. 1,6-Methano[10]annulen-11-yl triflate reacts in [BMIM][NTf2] to give 1,6-methano[10]annulen-11-ol, along with naphthalene, an oxidized product derived from loss of trifluoromethanesulfinate ion. Analogous loss of CF3SO2- can be seen in reaction of PhCH(CF3)OTf. Ionic liquids are therefore viable solvents for formation of carbocationic intermediates via kC and kDelta processes. 相似文献
97.
98.
David L. Willis 《Experimental Techniques》1980,4(4):23-28
Small, rugged, low power telemetry components have been developed which will withstand the hostile environment of many industrial applications. Consideration of the problems associated with low-level strain-gage signals has resulted in improved telemetry transmitter designs which overcome many of the shortcomings found in earlier designs. This equipment has been proven by hundreds of hours of operation during gas-turbine test-stand operation and helicopter flight test. 相似文献
99.
It is shown that the divergences associated with antinormally ordered forms of boson operators, as discovered computationally by Baltin, is due to an unjustifiable interchange of order of summation. 相似文献
100.
Barry CS Elsworth JD Seden PT Bushby N Harding JR Alder RW Willis CL 《Organic letters》2006,8(15):3319-3322
[Structure: see text] The total synthesis of the marine metabolite clavosolide A is reported which confirms the structure and absolute configuration of the natural product as the symmetrical diolide glycosylated by permethylated D-xylose moieties, 2. 相似文献