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51.
P. Koenig und Wilhelm Müller 《Zeitschrift für Lebensmitteluntersuchung und -Forschung A》1936,71(2):121-137
Zusammenfassung Die Konservierung von Tabakfabrikaten, um sie vor dem Muffigwerden und Verschimmeln sowie vor der Gärung (Kautabak) zu schützen, dürfte so alt sein wie die Tabakfabrikation selbst; namentlich gilt dies für den Kautabak, der sich früher einer viel weiter gehenden Verwendung erfreute als heute. Eine eingehende Bearbeitung hat das Problem der Tabakkonservierung (physikalisch und chemisch) bisher noch nicht erfahren.Die Versuche erstreckten sich nur auf die Konservierung mit chemischen Mitteln. Durch Umfrage in der Tabakindustrie wurden die hier gebräuchlichen Mittel festgestellt.Die Versuche bringen zunächst einen Vergleich der Konservierungsmittel auf einem Agar-Nährboden. Bei ihrer Prüfung auf Tabak (Tabakfabrikate zu Rauchzwecken) wurden Schnittbreite, Menge und Zusammensetzung der Soßierung, Beschaffenheit des Tabaks und Wassergehalt berücksichtigt.Aus der Bewertung der geprüften Konservierungsmittel für ihre Eignung zur Schimmelverhütung auf Rauchtabak ergibt sich die folgende abnehmende Reihenfolge hinsichtlich der wirksamen Zusatzmengen: Chinosol, Ester der p-Oxybenzoesäure und deren Natriumsalze (als Handelspräparate unter den Namen Solbrol, Nipagin, Nipasol usw. erhältlich), Benzoesäure, Natriumbenzoat. Die in der Reihenfolge nun folgenden Mittel, nämlich Salicylsäure, Natriumformiat und Borsäure halten wir infolge ihrer verhältnismäßig geringen konservierenden Wirkung auf Tabak für nicht geeignet.Andere Eigenschaften der Mittel, z. B. ihre praktische Verarbeitungsmöglichkeit und etwaige Beeinflussung des Tabaks, sind hierbei nicht berücksichtigt.Die Versuche sollen vorerst nur die Brauchbarkeit bestimmter chemischer Stoffe als Konservierungsmittel für Tabak zeigen; sie lassen dagegen die Frage der von den näheren Umständen abhängigen Notwendigkeit der Anwendung eines Konservierungsmittels bei den einzelnen Tabakerzeugnissen unberührt. 相似文献
52.
Waldemar Kröner und Wilhelm Völksen 《Zeitschrift für Lebensmitteluntersuchung und -Forschung A》1943,85(2):169-172
Ohne ZusammenfassungDiese Z.83, 193 (1942). 相似文献
53.
Ravindranath G. Naick Wilhelm Pritzkow Jürgen Rasche 《Advanced Synthesis \u0026amp; Catalysis》1977,319(5):785-789
On the Autoxidation of Bicyclo[2,2,2]octene During the autoxidation of bicyclo[2,2,2]octene at 90°C about 50% of epoxide are obtained. The most important byproduct obviously is a polymeric peroxide. From the acidic products formed in low amounts, cis-1, 4-Cyclohexane dicarboxylic acid could be isolated as the corresponding dimethyl ester. 相似文献
54.
Imola Wilhelm Judit Molnár Csilla Fazakas János Haskó István A. Krizbai 《International journal of molecular sciences》2013,14(1):1383-1411
The majority of brain metastases originate from lung cancer, breast cancer and malignant melanoma. In order to reach the brain, parenchyma metastatic cells have to transmigrate through the endothelial cell layer of brain capillaries, which forms the morphological basis of the blood-brain barrier (BBB). The BBB has a dual role in brain metastasis formation: it forms a tight barrier protecting the central nervous system from entering cancer cells, but it is also actively involved in protecting metastatic cells during extravasation and proliferation in the brain. The mechanisms of interaction of cancer cells and cerebral endothelial cells are largely uncharacterized. Here, we provide a comprehensive review on our current knowledge about the role of junctional and adhesion molecules, soluble factors, proteolytic enzymes and signaling pathways mediating the attachment of tumor cells to brain endothelial cells and the transendothelial migration of metastatic cells. Since brain metastases represent a great therapeutic challenge, it is indispensable to understand the mechanisms of the interaction of tumor cells with the BBB in order to find targets of prevention of brain metastasis formation. 相似文献
55.
Thomas Fend Wilhelm Völker Rolf Miebach Olena Smirnova Daniel Gonsior Daniel Schöllgen Peter Rietbrock 《International Journal of Heat and Mass Transfer》2011,54(19-20):4175-4181
The results of experimental investigations of novel ceramic high-temperature heat exchangers (HTHE) and its main characteristics such as effectiveness and power load as a function of mass flow and the geometry of the channels are presented. Firstly, some information on the background and the manufacturing of the HTHE, which is based on honey comb structures made out of extruded silicon carbide, is given. The experimental tests have been carried out with air as a heat transfer medium at temperatures of up to 1000 °C. The experimental set-up is described in detail. The acquired characteristic temperature and effectiveness data for different inlet temperatures and mass flows are discussed. They have been compared with data from theoretical calculations as well as with characteristic data of typical counter flow heat exchangers. Additionally, thermal shock tests have been carried out for a qualitative testing of the mechanical strength. Finally, a conclusion and an outlook on further activities are given. 相似文献
56.
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58.
Vinodh A. Edward Melanie Huch Carine Dortu Philippe Thonart Moutairou Egounlety Petrus J. Van Zyl Suren Singh Wilhelm H. Holzapfel Charles M.A.P. Franz 《Food Control》2011,22(3-4):389-395
Based on their predominance in Gari fermentations, as well as suitable technological properties, Lactobacillus plantarum, Lactobacillus fermentum, Weissella paramesenteroides and Leuconostoc mesenteroides strains were investigated for their suitability for development as starter strains for this African traditional fermented cassava product. The strains were grown in optimized growth media in 2 L fermenters, harvested and freeze dried, and then tested in lab-scale cassava mash fermentation trials for their ability to ferment the cassava. The strains performed well and rapidly increased the titratable acidity from 1.1 to 1.3% at 24 h to 1.3–1.6% at 48 h. The benefit of including starter cultures was that it lowered the pH of the product much faster and to lower levels than in the uninoculated control fermentation. The results furthermore indicated that especially the L. plantarum-group strains could be produced as starter strains at low cost. Overall, the results of this study showed that starter strains could be easily and economically produced, and thus represent a feasible possibility for further development for application in the field. 相似文献
59.
Hofmann Wilhelm; De Houwer Jan; Perugini Marco; Baeyens Frank; Crombez Geert 《Canadian Metallurgical Quarterly》2010,136(3):390
This article presents a meta-analysis of research on evaluative conditioning (EC), defined as a change in the liking of a stimulus (conditioned stimulus; CS) that results from pairing that stimulus with other positive or negative stimuli (unconditioned stimulus; US). Across a total of 214 studies included in the main sample, the mean EC effect was d = .52, with a 95% confidence interval of .466–.582. As estimated from a random-effects model, about 70% of the variance in effect sizes were attributable to true systematic variation rather than sampling error. Moderator analyses were conducted to partially explain this variation, both as a function of concrete aspects of the procedural implementation and as a function of the abstract aspects of the relation between CS and US. Among a range of other findings, EC effects were stronger for high than for low contingency awareness, for supraliminal than for subliminal US presentation, for postacquisition than for postextinction effects, and for self-report than for implicit measures. These findings are discussed with regard to the procedural boundary conditions of EC and theoretical accounts about the mental processes underlying EC. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
60.
In the present study, we investigate the two-dimensional laminar flow through a one-sided constriction of a plane channel with a ratio of h:H=1:4 (where h is the step height and H is the channel height). The computational approach employed is based on a mixed implicit/explicit time discretization scheme together with a highly accurate spatial discretization using a P
N
–P
N–2 spectral-element method. It is well known that this so-called forward-facing step (FFS) flow exhibits a singularity in the pressure and the velocity derivatives at the corner point. We account for this singularity by a geometric mesh refinement strategy that was proposed in a hp-FEM context. A detailed numerical study of the FFS flow reveals that length and height of the recirculation zone in front of the step are almost constant for creeping flow. In the limit of high Reynolds numbers the length and height of the recirculation zone increase proportional to Re
0.6 and Re
0.2, respectively. 相似文献