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排序方式: 共有277条查询结果,搜索用时 46 毫秒
271.
Adsorption probability measurements (molecular beam scattering) have been conducted to examine the adsorption dynamics (i.e. the gas-surface energy transfer processes) of CO2 adsorption on the Zn-on-Cu(1 1 0) bimetallic system. The results indicate surface alloy formation, which is in agreement with prior studies. Depositing Zn at 300 K on Cu(1 1 0), above the condensation temperature of CO2, leads to a “blocking” of CO2 adsorption sites by Zn which is incorporated in the Cu(1 1 0) surface. This apparent site blocking effect indicates a lowering of the CO2 binding energy on the alloyed surface as compared with the clean Cu(1 1 0) support. The Zn coverage has been calibrated by Auger electron spectroscopy and thermal desorption spectroscopy. 相似文献
272.
P. Flor H. Lausch P. Funk E. Szirucsek F. Schweiger R. Mück W. Philipp W. Gröbner W. Vogel H. Hornich W. Hazod L. Schmetterer Th. Sexl 《Monatshefte für Mathematik》1967,71(3):270-288
Ohne Zusammenfassung 相似文献
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275.
Gahagan KT Moore DS Funk DJ Rabie RL Buelow SJ Nicholson JW 《Physical review letters》2000,85(15):3205-3208
We have measured the rise time of laser-generated shock waves in vapor plated metal thin films using frequency-domain interferometry with subpicosecond time resolution. 10%- 90% rise times of <6.25 ps were found in targets ranging from 0.25 to 2.0 microm in thickness. Particle and average shock velocities were simultaneously determined. Shock velocities of approximately 5 nm/ps were inferred from the measured free surface velocity, corresponding to pressures of 30-50 kbar. Thus, the shock front extends only a few tens of lattice spacings. 相似文献
276.
Radim Horák Kamil Kořistek Veronika Šamšulová Ludmila Slaninová Martin Grepl Lubomír Kvapil Petr Funk Pavel Hradil Miroslav Soural 《Journal of heterocyclic chemistry》2020,57(4):1605-1615
Compounds bearing [1,3]dioxolo-quinoline scaffolds have been found in quinoline-based natural products; the only exception is the [1,3]dioxolo[4,5-c]quinoline moiety with a rare occurrence in both natural and synthetic derivatives. In this article, we report the preparation of diversely substituted and functionalized [1,3]dioxolo[4,5-c]quinolines using [1,3]dioxolo[4,5-c]quinoline-4-carbaldehyde (DQC) as the common intermediate. DQC was synthesized on a large scale from anthranilic acid and chloroacetone as the starting materials, with the rearrangement of acetonyl-anthranilate as the key step. The developed method allows for the simple preparation of [1,3]dioxolo[4,5-c]quinolines with various C2 substituents on the quinoline scaffold. Additionally, the synthetic route was successfully applied to the preparation of 3-hydroxyquinoline-4(1H)-ones. The target compounds were tested against representative Gram-positive/negative bacteria, and two derivatives exhibited submicromolar minimum inhibitory concentrations against Micrococcus luteus. 相似文献
277.
Use of solid-phase synthesis for the derivatization of carboxylic acids with biotinylated spacers consisting of ethylenoxy units is described. An aminomethylated resin provided with an acid-labile aldehyde linker is used as the polymer support and three different systems with a reactive amino group are introduced. Acylation of each system was tested with a set of model carboxylic acids and afforded crude products of excellent purity. The preloaded resins are similar to the Biotin-PEG-NovaTagTM resin but offer several advantages including simple elongation of the spacer arm. The protocols described represent a very efficient way of modifying compounds to obtain ligands for affinity chromatography studies. 相似文献