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41.
Volker Schusdziarra Margit Hausmann Claudia Wittke Johanna Mittermeier Marietta Kellner Aline Naumann Stefan Wagenpfeil Johannes Erdmann 《Nutrition journal》2011,10(1):5
Objective
The role of breakfast energy in total daily energy intake is a matter of debate. Acute feeding experiments demonstrated that high breakfast energy leads to greater overall intake supported by cross-sectional data of a free-living population. On the other hand, a large intraindividual analysis has indicated that a high proportion of breakfast to overall intake is associated with lower daily energy intake. To evaluate these apparently contradictory results in greater detail both ways of analysis were applied to the same data set of dietary records. 相似文献42.
Himani Gaur Jain Hatice Karacuban David Krix Hans-Werner Becker Hermann Nienhaus Volker Buck 《Carbon》2011,49(15):4987-4995
Well aligned carbon nanowalls, a few nanometers thick, were fabricated by continuous flow of aluminum acetylacetonate (Al(acac)3) without a catalyst, and independent of substrate material. The nanowalls were grown on Si, and steel substrates using inductively coupled plasma-enhanced chemical vapor deposition. Deposition parameters like flow of argon gas and substrate temperature were correlated with the growth of carbon nanowalls. For a high flow of argon carrier gas, an increased amount of aluminum in the film and a reduced lateral size of the carbon walls were found. The aluminum is present inside the carbon nanowall matrix in the form of well crystallized nanosized Al4C3 precipitates. 相似文献
43.
Dr. Gunther Kolb Dipl.‐Ing. Hans‐Joachim Kost Prof. Dr. Volker Hessel Prof. Dr. Volker Hessel 《化学,工程师,技术》2011,83(4):465-478
In this contribution it is reported about the realization of efficient micro rectification equipment (MRA), which can be operated intermittently or continuously and be used both for analytical as well as for preparative separations of mixtures of liquid substances. Different binary systems were separated. A theoretical separation stage number of 12 was obtained together with a height equivalent to one theoretical plate of 1.08 cm. Compared to the state of microtechnology this can be regarded as an excellent progress. 相似文献
44.
Dipl.‐Ing. Volker Lenz Dipl.‐Ing. Marian Schenker Dipl.‐Ing. Christian Thiel Prof. Dr. Wolf‐Dietrich Einicke M.Sc. René Bindig Dr. rer. nat. Ulf Roland 《化学,工程师,技术》2011,83(3):371-376
In addition to the reduction of particulate matter, a catalytic supported emission reduction in small scale biomass combustion systems can also enable a conversion of toxic organic components into carbon dioxide and water. For catalyst investigations under practical conditions a special test facility was designed. The results show that products of incomplete combustion like carbon monoxide from stoves can be reduced by catalytic processes. Further developments and studies are necessary to achieve the targeted emission limits. 相似文献
45.
Dr. Sven Nerdinger Eugene Kuatsjah Dr. Timothy E. Hurst Inge Schlapp‐Hackl Prof. Dr. Volker Kahlenberg Prof. Dr. Klaus Wurst Prof. Dr. Lindsay D. Eltis Prof. Dr. Victor Snieckus 《Chembiochem : a European journal of chemical biology》2018,19(16):1771-1778
A series of alkylated 2,3‐dihydroxybiphenyls has been prepared on the gram scale by using an effective Directed ortho Metalation–Suzuki–Miyaura cross‐coupling strategy. These compounds have been used to investigate the substrate specificity of the meta‐cleavage dioxygenase BphC, a key enzyme in the microbial catabolism of biphenyl. Isolation and characterization of the meta‐cleavage products will allow further study of related processes, including the catabolism of lignin‐derived biphenyls. 相似文献
46.
47.
Marcus Weyd Christian Pflieger Andy Vogel Hannes Richter Volker Prehn Christiane Günther Frank Splittgerber Alessa Gäbler Daniel Kaulbars Patrick Bräutigam Marcus Franke Samira Lambertz Julian Schlechtweg Ingolf Voigt 《化学,工程师,技术》2021,93(9):1432-1439
Reducing micropollutant pollution of water bodies is an important objective of water management and an integral part of environmental policy. Ceramic nanofiltration membranes were developed as multichannel membranes of increased membrane area and rotating disk filters. The membranes developed show retention of over 80 % for PEG 400. The membranes are currently being tested for the separation of micropollutants from wastewater contaminated with pharmaceuticals. With the help of a downstream oxidative process, the trace substances remaining in the permeate are degraded. 相似文献
48.
49.
Marie Stiborová Eva Frei Heinz H. Schmeiser Volker M. Arlt Václav Martínek 《International journal of molecular sciences》2014,15(6):10271-10295
This review summarizes the results found in studies investigating the enzymatic activation of two genotoxic nitro-aromatics, an environmental pollutant and carcinogen 3-nitrobenzanthrone (3-NBA) and a natural plant nephrotoxin and carcinogen aristolochic acid I (AAI), to reactive species forming covalent DNA adducts. Experimental and theoretical approaches determined the reasons why human NAD(P)H:quinone oxidoreductase (NQO1) and cytochromes P450 (CYP) 1A1 and 1A2 have the potential to reductively activate both nitro-aromatics. The results also contributed to the elucidation of the molecular mechanisms of these reactions. The contribution of conjugation enzymes such as N,O-acetyltransferases (NATs) and sulfotransferases (SULTs) to the activation of 3-NBA and AAI was also examined. The results indicated differences in the abilities of 3-NBA and AAI metabolites to be further activated by these conjugation enzymes. The formation of DNA adducts generated by both carcinogens during their reductive activation by the NOQ1 and CYP1A1/2 enzymes was investigated with pure enzymes, enzymes present in subcellular cytosolic and microsomal fractions, selective inhibitors, and animal models (including knock-out and humanized animals). For the theoretical approaches, flexible in silico docking methods as well as ab initio calculations were employed. The results summarized in this review demonstrate that a combination of experimental and theoretical approaches is a useful tool to study the enzyme-mediated reaction mechanisms of 3-NBA and AAI reduction. 相似文献
50.
The seed oil of Sebastiana commersoniana (Euphorbiaceae) was separated into a triglyceride and an estolide fraction by preparative thin-layer chromatography. The
triglyceride band was characterized by spectroscopic methods, and its fatty acids have been analyzed by gas chromatography
(GC) and GC-mass spectrometry (MS) and their methyl esters. Linolenic acid was the main fatty acid (65%). The estolide band
was examined by a combination of spectroscopic and chromatographic methods (ultraviolet, infrared, nuclear magnetic resonance,
fast atom bombardment-MS, GC-MS of the fatty acids before and after silylation) and was identified as a tetraglyceride, where
on α-carbon of the glyceride backbone was esterfied with 8-hydroxy-5,6-octadienoic acid, which itself was esterfied with trans-2,cis-4-decadienoic acid. The remaining positions of the glyceride backbone were occupied by common fatty acids.
This work was presented in part at the 87th Annual Meeting of the American Oil Chemists’ Society, April 28–May 1, 1996, Indianapolis,
Indiana. 相似文献