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991.
A procedure is described for the analysis of fatty acids (C12-C18 individually and C18+ as a group) in hops, hop extracts and isomerized hop extracts, and analytical results are quoted for twenty-one different samples of hops or hop products. Isomerized extracts varied widely in their content of fatty acids and isomerization and processing of hops appeared to eliminate some fatty acids selectively so that isomerized extracts were enriched in palmitic acid, linoleic acid and linolenic acid. Some hop extracts had a surprisingly high content of lauric acid. The analytical results are discussed in relation to gushing. 相似文献
992.
Sven Herrmann Ertan Göklü Hauke Müntinga Andreas Resch Tim van Zoest Hansjörg Dittus Claus Lämmerzahl 《Microgravity science and technology》2010,22(4):529-538
The realization of a Bose Einstein condensate in the Bremen drop tower as achieved by the QUANTUS collaboration in 2007 has
added a new field to microgravity research: the study of freely evolving degenerate quantum gases at largely extended evolution
times. Here we give an outlook on some experiments that could be done with such ultra-cold quantum gases in this unique laboratory
and on other microgravity platforms to study fundamental physics questions. In particular we consider experiments that could
employ the increased precision of matter wave interferometers in microgravity to search for low-energy phenomena of quantum
gravity. 相似文献
993.
Low‐fat Cheddar cheese made using microparticulated whey proteins: Effect on yield and cheese quality 下载免费PDF全文
Jessica A Stankey Yanjie Lu Abdelmoneim Abdalla Selvarani Govindasamy‐Lucey John J Jaeggi Bente Ø Mikkelsen Kenneth T Pedersen Claus B Andersen 《International Journal of Dairy Technology》2017,70(4):481-491
Influence of different levels (0, 0.15, 0.35 or 0.50%) of microparticulated whey protein (MWP) on yield and quality of low‐fat (~7.3 g/100 g) Cheddar cheese was investigated. MWP improved cheese yield due to the water‐binding ability of denatured whey protein. MWP addition decreased meltability but improved the textural properties beneficial for shredding and slicing, by decreasing sensory firmness. The results emphasise the role of MWP as an inert filler within cheese matrix, in improving cheese yield and creating a softer texture without compromising the sensory or overall quality of cheese, even with moisture increases in 0.35 or 0.50% MWP cheeses. 相似文献
994.
In this study the FA compositions of healthy and cancerous human renal tissues from the same patients are compared with special
reference to the CLA and PUFA content. CLA was preferentially incorporated into neutral lipid compared with phospholipid classes.
Its distribution profile was similar to that of monounsaturated FA, but unlike that found with 18∶2n−6. Different incorporation
patterns were found for individual CLA isomers. Comparing renal cell carcinoma (RCC) and healthy kidney, the total CLA content
was significantly lower in the cholesterylester fraction and significantly higher in the PE and PS fractions from RCC. The
most significant differences between healthy and cancerous renal tissue were in the content of t10,c12-CLA. Furthermore, the lipid class distributions of n−6 PUFA were determined, and several significant differences between
RCC and healthy renal tissue were found. This is of interest, as it has been proposed that the anticarcinogenic properties
of dietary CLA are associated with their interference in the metabolism of 20∶4n−6. The involvement of CLA in preventing renal
cancer cannot be definitively demonstrated from the design of this study, nor was it intended, but the complete determination
of the FA composition of adjacent healthy and cancerous tissues may provide an insight if lipids are involved in this disease. 相似文献
995.
The volatile components of the chin gland secretion of the wild European rabbit, Oryctolagus cuniculus (L.), were investigated with the use of gas chromatography. Studies of the chemical nature of this secretion by previous workers demonstrated that it was important in the maintenance of social structure in this species. This study identified 34 different volatile components that consist primarily of aromatic and aliphatic hydrocarbons. Especially common are a series of alkyl-substituted benzene derivatives that provide most of the compound diversity in the secretion. Samples of chin gland secretion collected from animals at three different geographical locations, separated by more than 100 km, showed significant differences in composition. This work suggests that variation among populations needs to be considered when undertaking semiochemical research. Alternate nonparametric methods are also used for the analysis of chromatographic data. 相似文献
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The first section of this paper defines the Deutsche Bundespost concept of ISDN, the services to be integrated, and the various ISDN components. The second and third parts of the paper cover the ISDN Pilot project and the offering of commercial ISDN services in the Federal Republic of Germany. The implementation strategy is briefly shown together with some outlook of the integration of broad-band services into ISDN. The last part describes strategic development toward an integrated services universal network, offering all kinds of telecommunication services including individual communication as well as broadcast services such as radio and TV program distribution. 相似文献
1000.
R. O. Claus K. D. Bennett A. M. Vengsarkar K. A. Murphy 《Journal of Nondestructive Evaluation》1989,8(2):135-145
Optical fiber waveguides embedded within materials have been applied to the measurement of chemical changes, strain, and temperature inside materials. This paper reviews some of the research that has been performed in this area over the past 10 years and cites the theoretical and demonstrated performance of such sensors for material evaluation during its manufacturing, in service lifetime and degradation periods. 相似文献