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61.
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Applied Biochemistry and Biotechnology - 相似文献
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David T. Hill Kerry G. Stanley Susan S. Libsch Bernard Loev 《Journal of heterocyclic chemistry》1976,13(6):1325-1326
Zinc-acetic acid reduction of 2,2′-dicyanoazobenzene affords, beside the expected 5-amino-indazolo[2,3-a]quinazoline, the previously unreported parent compound: indazolo[2,3-a]quin-azoline. 相似文献
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Randall J. Swift 《随机分析与应用》2013,31(5):583-616
The class of harmonizable processes and fields are a natural extension of the class of stationary processes and fields. Random fields admit an additional property called isotropy. The classical spectral and covariance representations for stationary isotropic random fields are extended to the harmonizable isotropic case. A classification of these fields is obtained based upon the smoothness properties of their covariances. In contrast to the stationary case, it is also shown that there exist non-trivial harmonizable isotropic fields which satisfy the Laplace operator in the L 2-sense 相似文献
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Dr. Karlee P. Castro Dr. Tyler T. Clikeman Nicholas J. DeWeerd Dr. Eric V. Bukovsky Kerry C. Rippy Dr. Igor V. Kuvychko Dr. Gao‐Lei Hou Dr. Yu‐Sheng Chen Dr. Xue‐Bin Wang Dr. Steven H. Strauss Dr. Olga V. Boltalina 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(12):3930-3936
In a simple, one‐step direct trifluoromethylation of phenazine with CF3I we prepared and characterized nine (poly)trifluoromethyl derivatives with up to six CF3 groups. The electrochemical reduction potentials and gas‐phase electron affinities show a direct, strict linear relation to the number of CF3 groups, with phenazine(CF3)6 reaching a record‐high electron affinity of 3.24 eV among perfluoroalkylated polyaromatics. 相似文献
69.
Dr. Bartholomäus Pieber Dr. Menny Shalom Prof. Dr. Markus Antonietti Prof. Dr. Peter H. Seeberger Dr. Kerry Gilmore 《Angewandte Chemie (International ed. in English)》2018,57(31):9976-9979
Solid reagents, leaching catalysts, and heterogeneous photocatalysts are commonly employed in batch processes but are ill‐suited for continuous‐flow chemistry. Heterogeneous catalysts for thermal reactions are typically used in packed‐bed reactors, which cannot be penetrated by light and thus are not suitable for photocatalytic reactions involving solids. We demonstrate that serial micro‐batch reactors (SMBRs) allow for the continuous utilization of solid materials together with liquids and gases in flow. This technology was utilized to develop selective and efficient fluorination reactions using a modified graphitic carbon nitride heterogeneous catalyst instead of costly homogeneous metal polypyridyl complexes. The merger of this inexpensive, recyclable catalyst and the SMBR approach enables sustainable and scalable photocatalysis. 相似文献
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Porphyrin-metal complexes are potentially useful to catalyze redox reactions, which convert toxic and biologically recalcitrant
compounds to compounds that are less toxic and more amenable to biotreatment. Porphyrins, in the absence of proteins as in
ligninases, peroxidases, and oxidases, are potentially more robust than enzymes and microbial cultures in the treatment of
inhibitory substances.
2,4,6-Trichlorophenol was used as a model compound for chlorinated phenols and as a substrate for various porphyrin-metal
complexes acting as oxidation catalysts. t-Butyl hydroperoxide was the oxidizing agent. TCP was shown to be at least partially
dechlorinated and the aromatic ring broken in reaction products. All porphyrins exhibited saturation kinetics with regard
to the initial TCP concentration in reaction mixtures. Electron-withdrawing substituents on the porphyrins were observed to
increase stability of the catalysts to inactivating ring-centered oxidation. 相似文献