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81.
Go Gwang Sub Lee Hong Joo Moon Dong Ju Kim Young Chul 《Research on Chemical Intermediates》2016,42(1):289-304
Research on Chemical Intermediates - In this study, we focused on the catalytic activity, stability, and kinetics of glycerol steam reforming (GSR) for the hydrogen production over... 相似文献
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Becerril R Gómez-Lus R Goñi P López P Nerín C 《Analytical and bioanalytical chemistry》2007,388(5-6):1003-1011
The aim of this work is the optimization and application of a group of analytical and microbiological techniques in the study
of the activity of essential oils (EOs) incorporated in a new antimicrobial packaging material and the research in depth of
the interaction between the microbial cells and the individual compounds present in the active material. For this purpose
the antimicrobial activity of the active packaging containing cinnamon or oregano was evaluated against E. coli and S. aureus. The vapour phase activity and the direct contact between the antimicrobial agents themselves, or once incorporated in the
packaging material, and the microbial cells have been studied. The direct contact was studied using a broth dilution method.
The vapour phase was evaluated by using a new method which involves the use of a filter disk containing the EOs. Furthermore,
the kill time assay was used to determine the exposure time for the maximum efficiency in packaging, and transmission electron
microscopy was used to investigate the antimicrobial activity and the possible mechanism of action against E. coli and S. aureus. Finally, the compounds absorbed by cells were identified. The results showed that the techniques used provide relevant information
about the antibacterial activity of cinnamon and oregano in direct contact as well as in the vapour phase. The antimicrobial
packaging showed a fast efficiency which supports its likely application as a food packaging material. Bacteria treated with
EOs exhibit a wide range of significant abnormalities; these include formation of blebs, coagulation of cytoplasmatic constituents,
collapse of the cell structure and lack of cytoplasmatic material. Some of these observations are correlated to the ability
of some of these substances to disrupt envelop structure, especially the inner membrane. After an extraction from dead cells,
cinnamaldehyde was detected by GC-MS in E. coli exposed to the active packaging containing cinnamon. 相似文献
84.
Calix[4]bis(thiacrown-5) (L) with 1,3-alternating conformation was employed as a strong dinucleating ligand for the soft metal ions AgI and CuI. The reaction of L with AgPF6 afforded a discrete endo-coordinated disilver(I) complex 1, [Ag2L](PF6)2. In contrast, mixed products (2a + 2b) consisting of 3D networks were obtained from the reaction of L and CuI; 2b linked with a Cu4I4 cubane unit was shown to generate photoluminescence, while 2a linked with a Cu2I2 rhomboid unit does not. 相似文献
85.
P. Fita K. Smoliński Z. Gołacki K. Lawniczak-Jablonska 《Applied Physics A: Materials Science & Processing》1999,68(6):681-685
The homogeneity, solid solubility, and chemical bonds in the new materials PbTe, SnTe doped with Ce were investigated. Scanning
electron microscope observation and electron probe microanalysis carried out on PbTe crystals doped with Ce, revealed three
types of Ce-rich precipitates with following compositions: CeTe2, Ce3Te7, Ce2Te5 and small admixture of PbTe in precipitates. The solubility of Ce in PbTe matrix was estimated as 0.5±0.1 at. %. The solubility
of PbTe in CeTe2 and Ce3Te7 was found to be 3±0.5 at. %, but 7±0.5 at. % in the case of Ce2Te5. In SnTe crystal doped with Ce only one kind of precipitate with composition Ce2SnTe5 was found. Cerium solubility in SnTe matrix was estimated to be 1±0.25 at. %. According to our knowledge this is the first
report of the identification of Ce2SnTe5 compound. The similar compounds Ce2SnS5 and Ce2SnSe5 are known.
Received: 9 December 1998 / Accepted: 9 February 1999 / Published online: 28 April 1999 相似文献
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The composition of the ion-association complex of Rhodamine B with silicomolybdate has been examined by Job's method and spectrophotometric titration. The ratio of Rhodamine B to silicon in the complex is 4 : 1. The same ratio is obtained by analysis of the crystalline complex. The composition of the complex is identical in aqueous medium, an organic solvent (ethanol) and in the crystalline state (C(28)H(30)N(2)O(3))(4)SiMo(12)O(40)). The complex is stable in the organic solvent and has its absorption maximum at 555 nm and a molar absorptivity of 5 x 10(5) 1.mole(-1)cm(-1). The complex can be advantageously used for the determination of silicon. 相似文献
89.
A palladium NNC‐pincer complex at a 5 mol ppm loading efficiently catalyzed the Hiyama coupling reaction of aryl bromides with aryl(trialkoxy)silanes in propylene glycol to give the corresponding biaryls in excellent yields. This method was applied to the syntheses of adapalene and a biaryl‐type liquid‐crystalline compound, as well as to the derivatization of dextromethorphan and norfloxacin. ESI‐MS and NMR analyses of the reaction mixture suggested the formation of pentacoordinate spirosilicate intermediates in situ. Preliminary theoretical studies revealed that the glycol‐derived silicate intermediates formed in situ are quite reactive silicon reagents in the transmetalation step. 相似文献
90.