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991.
Optical emission and Fourier transform infrared absorption diagnostics have been carried out in hexamethyldisiloxane/oxygen RF discharges for studying the effects of the feed composition and the power on the deposition of SiO2—like thin films. Ex situ FTIR absorption has been utilized to monitor organic moieties and silanol groups in the film. It is shown that carbon-free films can be obtained by highly diluting the monomer in oxygen, while medium-to-high power is necessary to abate silanol groups. These two conditions represent the optimization criterion to obtain excellent barrier films for food packaging applications. 相似文献
992.
Annovazzi L Cattaneo V Viglio S Perani E Zanone C Rota C Pecora F Cetta G Silvestri M Iadarola P 《Electrophoresis》2004,25(9):1255-1263
Tobacco smoke is involved in the pathogenesis of cardiovascular and respiratory diseases and also has a local toxic effect in the oral cavity. Low-aliphatic aldehydes, such as formaldehyde, acetaldehyde and acrolein, are among the main components of mainstream cigarette smoke and their local noxious and carcinogenic effects in the oral cavity and upper gastrointestinal tract are well-known. Although various studies have been performed so far to determine their content in cigarette smoke, none has included the direct measurement of these compounds in the saliva of smoking and nonsmoking subjects. Thus, in an attempt to verify whether typical chromatographic (high-performance liquid chromatography, HPLC) and/or electrophoretic (capillary electrophoresis, CE) techniques could be reliable methods for determining the levels of these analytes in human saliva, we submitted specimens obtained from a selected population of heavy, moderate, and nonsmoking subjects to HPLC and CE analyses. Both methods showed good reproducibility in terms of migration times and peak height and/or areas and had comparable linearity. Quantitative analyses performed on the specimens investigated evidenced a 3.5-fold increase of low-aliphatic aldehydes in saliva of nonsmoking subjects after they have smoked a single cigarette and a further 2-fold increase of these compounds in saliva of smokers with a daily consumption of 10 or more cigarettes. 相似文献
993.
Fabio Marchetti Claudio Pettinari Riccardo Pettinari 《Coordination chemistry reviews》2005,249(24):2909-2945
This review summarizes the literature on 4-acyl-5-pyrazolone ligands, their synthesis, characterization and coordination chemistry toward main group, transition, lanthanide and actinide metals and relevant applications of their metal complexes. 相似文献
994.
Attanasi OA de Crescentini L Favi G Filippone P Mantellini F Santeusanio S 《The Journal of organic chemistry》2002,67(23):8178-8181
The synthesis of 5-hydroxy-1-aminopyrroline-3-carboxylic acid derivatives and 5-unsubstituted-1-aminopyrrole-3-carboxylic acid derivatives from 1,2-diaza-1,3-butadienes and aldehydes is presented. These domino reactions offer the advantage of executing multistep transformation without intermediate workup procedures. The stereoselectivity of ring closure to 5-hydroxy-1-aminopyrroline-3-carboxylic acid derivatives and phenyl transposition to 2,3-diphenyl-1-aminopyrrole-3-carboxylic acid derivatives are also studied. 相似文献
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Briscese Fabio 《The European Physical Journal B - Condensed Matter and Complex Systems》2022,95(4):1-11
The European Physical Journal B - In this paper, we report the changes in structural and dynamical properties of a MgSiO3 liquid under compression via molecular dynamics simulation. The short-range... 相似文献
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