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51.
In order to investigate the relation between the structure of mono-branched saturated fatty acids and their physical properties,
a three-factor central composite design was constructed. For this purpose sixteen different fatty acids were prepared. The
synthetic strategy was to use if possible, a few common starting materials for the preparation of most of the acids. Thus
alkylation and hydrolysis of oxazolines were used for the preparation of 2-butylhexanoic acid, 2-methyloctadecanoic acid,
2-hexadecyloctadecanoic acid and 2-pentyloctadecanoic acid. A number of acids were prepared from thiophene derivatives followed
by desulfurization with Raney-Nickel alloy under alkaline conditions. Thus, starting from 3-ethylthiophene, 4-ethyl-2-thiophenecarboxylic
acid and 4-ethyl-2-methyl-5-thiophenecarboxylic acid were prepared, which upon desulfurization gave the desired 4-methylhexanoic
acid. From 3-bromo-2-methylthiophene, 3-ethyl-2-methyl-5-thiophenecarboxylic acid was preparedvia 3-acetyl-2-methylthiophene and 3-ethyl-2-methylthiophene. Desulfurization gave 4-ethylhexanoic acid. Another approach started
with 2-acylthiophenes, which were reacted with Grignard reagent to yield the appropriate olefins. By metalation and reaction
with carbon dioxide, these were transformed to the corresponding 2-thiophenecarboxylic acids. Upon desulfurization, the desired
fatty acids were obtained. In this way 6-propyldecanoic acid, 6-hexyldodecanoic acid, 6-methyldodecanoic acid and 6-pentylpentadecanoic
acid were prepared. The remaining four acids were prepared from some of the branched acids described above through Kolbe reactions
of dioic acids. Thus 16-methyloctadecanoic acid and 10-methyl-dodecanoic acid were obtained from 4-methylhexanoic acid, 16-ethyloctadecanoic
acid from 4-ethylhexanoic acid and 9-pentyloctadecanoic acid from 6-pentylpentadecanoic acid. 相似文献
52.
Laura Salo Fanni Mylläri Marek Maasikmets Ville Niemelä Alar Konist Keio Vainumäe 《Aerosol science and technology》2019,53(5):526-539
Particulate matter in the atmosphere is known to affect Earth’s climate and to be harmful to human health. Accurately measuring particles from emission sources is important, as the results are used to inform policies and climate models. This study compares the results of two ELPI?+?devices, two PM10 cascade impactors and an eFilter, in combustion emission measurements. The comparison of the instruments in a realistic setting shows what types of challenges arise from measuring an emission aerosol with unknown particle morphologies and densities, different particle concentrations and high temperature. Our results show that the PM10 cascade impactors have very good intercorrelation when the collected mass is greater than 150?µg, but below that, the uncertainty of the results increases with decreasing mass. The raw signals of two ELPI?+?devices were nearly identical in most samples, as well as the particle number concentrations and size distributions calculated from raw signals; however, transforming the current distributions into mass distributions showed variation in the mass concentration of particles larger than 1?µm. The real-time time signal measured by eFilter was similar to the total current measured by ELPI+. The eFilter and PM10 cascade impactors showed similar particle mass concentrations, whereas ELPI?+?showed clearly higher ones in most cases. We concluded that the difference is at least partially due to volatile components being measured by ELPI+, but not by the mass collection measurements.
Copyright © 2019 American Association for Aerosol Research 相似文献
53.
E. V. Bychkov V. D. Filatov S. N. Knyazev N. N. Konev I. P. Salo 《Glass and Ceramics》2000,57(9-10):328-329
It is demonstrated that magnetic separation of crushed bacor (virgin and recycled bacor waste) on the magnetic separator produced by ÉMKO Electromechanical company made it possible to improve the quality of the finished products. 相似文献
54.
S. V. Denisov M. A. Molostov P. A. Stekanov V. V. Savenkov V. Yu. Salo 《Steel in Translation》2008,38(7):574-576
The structure of an algorithm used in developing new production technologies for hot-rolled sheet with unique properties is proposed. As an example, the algorithm is applied to 17Γ1C-Y steel. The corresponding changes in the hot-rolling conditions and their influence on the mechanical properties of the product are considered. 相似文献
55.
Matti Verta Simo Salo Petri Porvari John Munthe 《The Science of the total environment》2010,408(17):3639-3647
We conducted a whole-lake experiment by manipulating the stratification pattern (thermocline depth) of a small polyhumic, boreal lake (Halsjärvi) in southern Finland and studying the impacts on lake mercury chemistry. The experimental lake was compared to a nearby reference site (Valkea-Kotinen Lake). During the first phase of the experiment the thermocline of Halsjärvi was lowered in order to simulate the estimated increase in wind speed and in total lake heat content (high-change climate scenario). The rate of methyl mercury (MeHg) production during summer stagnation (May-August) was calculated from water profiles before the treatment (2004), during treatment (2005, 2006) and after treatment (2007). We also calculated fluxes of MeHg from the epilimnion and from the hypolimnion to the sediments using sediment traps. Experimental mixing with a submerged propeller caused a 1.5-2 m deepening of the thermocline and oxycline. Methyl mercury production occurred mostly in the oxygen free layers in both lakes. In the experimental lake there was no net increase in MeHg during the experiment and following year; whereas the reference lake showed net production for all years. We conclude that the new exposed epilimnetic sediments caused by a lowering of the thermocline were a major sink for MeHg in the epilimnion. The results demonstrate that in-lake MeHg production can be manipulated in small lakes with anoxic hypolimnia during summer. The climate change induced changes in small boreal lakes most probably affect methyl mercury production and depend on the lake characteristics and stratification pattern. The results support the hypothesis that possible oxygen related changes caused by climate change are more important than possible temperature changes in small polyhumic lakes with regularly occurring oxygen deficiency in the hypolimnion. 相似文献
56.
Y Ding VJ Uitto M Haapasalo K Lounatmaa YT Konttinen T Salo D Grenier T Sorsa 《Canadian Metallurgical Quarterly》1996,75(12):1986-1993
Tissue destruction during periodontitis is believed to be primarily brought about by leukocyte proteinases. We postulate that oral spirochetes cause discharge of polymorphonuclear leukocyte (PMN) lysosomal enzymes. Effects of Treponema denticola 53-kDa outer membrane protein, lipopolysaccharide (LPS), and peptidoglycan on degranulation of matrix metalloproteinases (MMP)-8 (collagenase) and -9 (gelatinase), cathepsin G, and elastase by human peripheral blood PMNs were studied by specific enzyme assays and Western blot analysis. T. denticola 53-kDa kDa outer membrane protein was found to be a particularly efficient inducer of MMP-8 release. The induction was comparable with that of phorbol myristate acetate, a known inducer of PMN specific granule discharge. All of the treponemal substances, most notably the 53-kDa protein and LPS, induced release of MMP-9, a component of C-type granules. Both collagenase and gelatinase released from PMNs were mostly in active forms. Release of cathepsin G and elastase was also observed with the 53-kDa protein treatment. The other T. denticola substances did not induce release of these serine proteinases. Lactate dehydrogenase was not released from PMNs by the treatments, indicating that the degranulation was specific and not caused by toxic effects of the substances. This was confirmed by transmission electron microscopy of PMNs treated with the 53-kDa protein that showed rapid vacuole formation and cell shape changes but no disintegration of the cells. Thus, T. denticola may participate in the PMN-dependent extracellular matrix degradation during the course of periodontal inflammation by triggering the secretion and activation of matrix metalloproteinases. 相似文献
57.
58.
Tapio Salo und Kari Salminen 《Zeitschrift für Lebensmitteluntersuchung und -Forschung A》1963,124(6):448-449
Zusammenfassung Zur Trennung der p-Hydroxybenzoesäure und ihrer Methyl-, Äthyl-, Propyl-, Isopropyl-, Butyl-, Isobutyl-, Hexyl-, Heptyl-, Octyl-, Nonyl-, Dodecyl-, Phenyl-und Benzylester wurde ein dünnschichtchromatographisches Verfahren ausgearbeitet, bei dem als stationäre Phase ein Gemisch 1 : 1 (Gew-Teile ) von 10%ig acetylierter Cellulose und Polyamid und als bewegliche Phase das Zweikomponentensystem Shell Sol A : Eisessig 50:10 (Vol-Teile) angewandt wurde.[/p] 相似文献
59.
Ronkainen Pentti Salo Tapio Suomalainen Heikki 《European Food Research and Technology》1962,117(4):281-289
European Food Research and Technology - Die Carbonylverbindungen wurden aus französischen Weindestillaten Compte 0–5 mittels salzsaurer 2,4-Dinitrophenylhydrazinlösung gefällt.... 相似文献
60.
Rami Saarinen Janne Järvi Roope Raisamo Eva Tuominen Marjatta Kangassalo Kari Peltola Jouni Salo 《Virtual Reality》2006,9(2-3):108-117
Visually impaired children have a great disadvantage in the modern society since their ability to use modern computer technology is limited due to inappropriate user interfaces. The aim of the work presented in this paper was to develop a multimodal software architecture and applications to support learning of visually impaired children. The software architecture is based on software agents, and has specific support for visual, auditory and haptic interaction. It has been used successfully with different groups of 7-8 year-old and 12 year-old visually impaired children. In this paper we discuss the enabling software technology and interaction techniques aimed to realize our goal and our experiences in the actual use of the system. 相似文献