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81.
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Docking Strategy To Construct Thermostable,Single‐Crystalline,Hydrogen‐Bonded Organic Framework with High Surface Area 下载免费PDF全文
Dr. Ichiro Hisaki Yuto Suzuki Eduardo Gomez Dr. Boiko Cohen Dr. Norimitsu Tohnai Prof. Dr. Abderrazzak Douhal 《Angewandte Chemie (International ed. in English)》2018,57(39):12650-12655
Enhancing thermal and chemical durability and increasing surface area are two main directions for the construction and improvement of the performance of porous hydrogen‐bonded organic frameworks (HOFs). Herein, a hexaazatriphenylene (HAT) derivative that possesses six carboxyaryl groups serves as a suitable building block for the systematic construction of thermally and chemically durable HOFs with high surface area through shape‐fitted docking between the HAT cores and interpenetrated three‐dimensional network. A HAT derivative with carboxybiphenyl groups forms a stable single‐crystalline porous HOF that displays protic solvent durability, even in concentrated HCl, heat resistance up to 305 °C, and a high Brunauer–Emmett–Teller surface area [SA(BET)] of 1288 m2 g?1. A single crystal of this HOF displays anisotropic fluorescence, which suggests that it would be applicable to polarized emitters based on robust functional porous materials. 相似文献
84.
85.
L. A. Shibaev Yu. N. Sazanov N. G. Stepanov A. A. Boiko 《Journal of Thermal Analysis and Calorimetry》1989,35(3):947-954
Polymer compositions based on furyl alcohol and polyamic acid were investigated by using mass-spectrometric thermal analysis. It was established that polyamic acid catalyses both the polycondensation of furyl alcohol and the formation of a three-dimensional network of furan polymer.
Zusammenfassung Mittels massenspektroskopischer Thermoanalyse wurden auf Furylalkohol und Polyamidsäure basierende Polymergemische untersucht. Es wurde festgestellt, daß Polyamidsäure sowohl die Polykondensation von Furylalkohol als auch die Bildung eines dreidimensionalen Furanraumnetzes katalysiert.
- . , , .相似文献
86.
A study is reported of the angular distribution of monoenergetic electrons from a betatron which have traversed barriers of Al, Cu, and Pb with thicknesses reaching the extrapolated range. The initial electron energy is in the range 3–8 MeV. The experimental results agree well with Monte Carlo calculations carried out for identical calculations and with the results of earlier work for smaller barriers. The half-width of the electron angular distribution, increasing with increasing barrier thickness, reaches a nearly constant value, while the distribution itself corresponds to the laws of complete diffusion, i. e., converts into a distribution similar to cos2. As the thickness of the absorbers is increased further, the half-width decreases and the distribution becomes narrower, due to the penetration far into the absorbers of electrons which have been scattered predominantly in the forward direction.Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Fizika, No. 5, pp. 35–38, May, 1975. 相似文献
87.
V. I. Boiko V. V. Evstigneev N. N. Prilepskikh I. V. Shamanin 《Russian Physics Journal》1986,29(5):413-416
Using the small parameter method, a numerical solution is found for the nonlinear thermal conductivity equation describing evolution of the temperature field in an absorber after completion of a radiation pulse. High speed (106 K/sec) heating of the surface layers over 1·10–5 sec is observed. Absorber cooling parameters are obtained as a function of time and distance from the irradiated surface.Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Fizika, No. 5, pp. 89–93, May, 1986. 相似文献
88.
I. I. Boiko N. A. Derevyanko A. A. Ishchenko T. A. Markina A. I. Tolmachev 《Chemistry of Heterocyclic Compounds》1986,22(12):1295-1300
Symmetric 2-pyrylo- and asymmetric (indo)(2-pyrylo)trimethinecyanines with substituents of different electronic nature in the pyran residue were synthesized. The influence of the conjugation effect and inductive effect on the characteristics of absorption bands of the synthesized dyes was analyzed by a quantum chemical calculation according to a common MO Hückel method.For Communication 22, see [1].Translated from Khimiya Geterotsiklicheskikh Soedinenii No. 12, pp. 1607–1613, December, 1986. 相似文献
89.
T. D. Sokolova I. P. Boiko G. V. Cherkaev A. S. Moskovkin O. N. Khruleva 《Chemistry of Heterocyclic Compounds》1994,30(7):813-817
1,3(1,5)-dimethyl-2-phenyl- and -2,4-diphenyl-4 piperidols were respectively obtained with the reaction of 1,3-and 1,5-dimethyl-2 phenyl-4-piperidoraes with sodium borohydride and phenyllithium. The steric isomers of the compounds obtained were separated and identified by spectral methods.Moscow State Academy of Precision Chemical Technology, Moscow 117571. Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 7, pp. 941–945, July, 1994. Original submitted July 11, 1994. 相似文献
90.
T. D. Sokolova G. V. Cherkaev I. P. Boiko A. S. Moskovkin 《Chemistry of Heterocyclic Compounds》1997,33(6):676-679
The reaction of substituted 4-phenyl-4-piperidols with acetonitrile under Ritter reaction conditions leads to formation of mixtures of the corresponding 4-acetylamino-4-phenylpiperidines and 1,2,5,6-tetrahydropyridines, from which we isolated the target amides by fractional crystallization.M. V. Lomonosov State Academy of Fine Chemical Technology, Moscow 117571. Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 6, pp. 776–780, June, 1997. 相似文献