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61.
G. van den Hock D. Consalvo D. H. Parker J. Reuss 《Zeitschrift für Physik D Atoms, Molecules and Clusters》1993,27(1):73-78
The excited electronic origin bands of several DABCO containing van der Waals complexes have been observed via (1+1) resonance enhanced multi-photon ionization. Sharp resonances with widths of about 3 cm–1 are seen for DABCO-Rg
n=1,2,3 (Rg is Ar, Kr or Xe), for the DABCO-DABCO dimer and for DABCO-DABCO-Ar. The origins of the rare-gas complexes are blue shifted with respect to the monomer origin. Broad features originating from DABCO-Rg
n
complexes with highn, appear to higher energies than the complex origins, with widths of 120 cm–1. 相似文献
62.
63.
M. N. Dudinski W. K. Nikiforow P. Woog J. Givaudon P. Dacheux M. G. Schifrin W. T. Palwelew F. Zetzsche E. Ziegler K. Säuberlich G. A. Sikejew J. I. Kasakow H. Seebaum E. Hartmann V. Prever N. Foglino B. Steiger R. Juza R. Langheim H. Siebeneck W. Ulrich G. Edgar G. Calingaart E. W. Ellis C. Cândea E. Macovski H. Hock O. Schrader W. Susemihl J. A. Yule C. P. Wilson R. Vondráček J. Dostál C. H. Fisher A. Eisner Ch. M. Blair S. J. Kossolapow M. I. Jagnjatinski B. G. Šimek Z. Beránek G. Kraemer A. Spilker V. Sliva M. Marder W. Bielenberg F. N. Laird D. J. W. Kreulen R. Heinze 《Analytical and bioanalytical chemistry》1939,118(5-6):208-222
64.
Lucas Mertens Katharina J. Hock Prof. Dr. Rene M. Koenigs 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(28):9542-9545
A novel continuous‐flow approach for the synthesis of fluoroalkyl‐substituted diazomethanes has been developed. Utilizing a cheap, self‐made microreactor fluoroalkyl‐substituted amines were transformed into the corresponding diazomethanes using tert‐butyl nitrite and acetic acid as catalyst. These diazomethanes were employed in [2+3] cycloaddition reactions with olefins and alkynes, yielding valuable pyrazolines and pyrazoles in good to excellent yields. 相似文献
65.
Characterization
of supercooling suppression of microencapsulated phase change material by
using DSC 总被引:1,自引:0,他引:1
J. L. Alvarado C. Marsh C. Sohn M. Vilceus V. Hock G. Phetteplace T. Newell 《Journal of Thermal Analysis and Calorimetry》2006,86(2):505-509
Supercooling suppression of
microencapsulated n-tetradecane was measured
using differential scanning calorimetry. Results indicate that the degree
of supercooling is positively affected by the amount and type of nucleating
agent present in bulk and microencapsulated n-tetradecane
which it is used as a phase change material (MPCM). Results also demonstrate
that the melting point of the n-tetradecane
is fairly independent of nucleating agent concentration (0 – 4%). Conversely,
the latent heat of fusion of n-tetradecane
decreases considerably with nucleating agent amount and the initiation of
crystallization point is inversely proportional to cooling rate. 相似文献
66.
The effects on the radiation response of Harwell polymethylmethacrylate (PMMA) dosimeters of dose-rate, radiation type, temperature during irradiation and post-irradiation storage, and post-irradiation stability, are of importance to the operators of commercial irradiation facilities.
This paper describes recent studies of the effects of some of these parameters on the radiation response of Harwell Red 4034, Amber 3042, and Gammachrome YR Perspex dosimeters, and provides data on batch to batch variation and shelf-life. 相似文献
67.
In the Buchwald-Hartwig reaction between HIPTBr (HIPT = 3,5-(2,4,6-i-Pr3C6H2)2C6H3 = hexaisopropylterphenyl) and (H2NCH2CH2)3N, it is possible to obtain a 65% isolated yield of (HIPTNHCH2CH2)2NCH2CH2NH2. A second coupling then can be carried out to yield a variety of "hybrid" ligands, (HIPTNHCH2CH2)2NCH2CH2NHAr, where Ar = 3,5-Me2C6H3, 3,5-(CF3)2C6H3, 3,5-(MeO)2C6H3, 3,5-Me2NC5H3, 3,5-Ph2NC5H3, 2,4,6-i-Pr3C6H2, or 2,4,6-Me3C6H2. The hybrid ligands may be attached to Mo to yield [hybrid]MoCl species. From the monochloride species, a variety of other species such as [hybrid]MoN, {[hybrid]MoN2}Na, and {[hybrid]Mo(NH3)}+ can be prepared. [Hybrid]MoN2 species were prepared through oxidation of {[hybrid]MoN2}Na species with ZnCl2, but they could not be isolated. [Hybrid]Mo=N-NH species could be observed as a consequence of the protonation of {[hybrid]MoN2}- species, but they too could not be isolated as a consequence of a facile decomposition to yield dihydrogen and [hybrid]MoN2 species. Attempts to reduce dinitrogen catalytically led to little or no ammonia being formed from dinitrogen. The fact that no ammonia was formed from dinitrogen in the case of Ar = 3,5-Me2C6H3, 3,5-(CF3)2C6H3, or 3,5-(MeO)2C6H3 could be attributed to a rapid decomposition of intermediate [hybrid]Mo=N-NH species in the catalytic reaction, a decomposition that was shown in separate studies to be accelerated dramatically by 2,6-lutidine, the conjugate base of the acid employed in the attempted catalytic reduction. X-ray structures of [(HIPTNHCH2CH2)2NCH2CH2N{3,5-(CF3)2C6H3}]MoCl and [(HIPTNHCH2CH2)2NCH2CH2N(3,5-Me2C6H3)]MoN2}Na(THF)2 are reported. 相似文献
68.
The images used in phase-shifting interferometry are usually noisy and smoothing filters are frequently used. Filtering can be done on the fringe patterns before phase retrieving or on the phase map after phase retrieving. Filtering fringe patterns—a form of preprocessing, requires the same processing to be done on at least three patterns. Filtering phase map, on the other hand, needs processing of only one pattern. Preprocessing prevents noise from being carried through while post-processing might clip parts of the signal. Thus there is a need to evaluate which one is better. A theoretical analysis was carried out for this basic problem, followed by computer simulations and a real experiment for verification. The comparison was also extended to phase difference measurement which uses similar but slightly different phase retrieval algorithms. 相似文献
69.
70.