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排序方式: 共有791条查询结果,搜索用时 11 毫秒
771.
772.
Volatile products of precursor carbon fibres of petroleum pitch oxidized in oxygen were investigated. Concentration changes in CO, CO2, and H2O as a function of temperature and oxidation time were determined quantitively by gas chromatrography. The oxidation of precursor pitch fibres is the most efficient in the temperature range between 453–498 K during 2–4 hours. 相似文献
773.
The behaviour of thin-walled structures has been a very important area of research activity in the Department of Strength of Materials and Structures (previously the Institute of Applied Mechanics) of the Technical University of
ódź in Poland for over 30 years.The investigations concerned many kinds of thin-walled structures: plates of different shapes including trapezoidal and circular, girder and column structures composed of flat plates, cylindrical and conical shells, and composite multi-layer structures subjected to a variety of load types.The analyses included buckling and post-buckling behaviour, assessment of ultimate loads and the behaviour of the structure in post post failure range. This necessitated usage of the theory of elasticity and elasto plasticity in the constitutive relations describing phenomena of the materials behaviour. All the works done at our Department resulted in a number of papers and books, achieved academic degrees and titles (PhD, DSc, Professor). They were also presented in numerous conferences, symposia and seminars.It is our academic duty and a pleasure to mention that for about 20 years we have been accompanied in our thin-walled research activity by our sister unit from the University of Strathclyde-the Department of Mechanical Engineering. Some of our achievements would not be possible without this valuable collaboration, which was part of a more general scheme of academic link initiated between our universities almost 30 years ago. 相似文献
774.
M De Vincenzi E Badellino S Di Folco A Dracos M Magliola A Stacchini P Stacchini V Silano 《Food Additives & Contaminants》1989,6(2):235-267
Quantitative data on volatile compounds have been reported in 16 food items. No publications reporting quantitative data were found for two of these 16 food products, i.e. avocado and jackfruit. About 550 volatile compounds have been assayed globally in the other 14 food products. Mango and raspberry were the products with the greatest number of volatile compounds; the most representative substances were benzaldehyde, ethyl acetate, limonene, and 2-phenylethanol. 相似文献
775.
The advisability of drug withdrawal has recently become an important issue in light of several effects of long-term drug maintenance, including undesirable side effects, unexplained deaths, mounting costs, problems in drug-state learning and transfer of learning to the nondrug state, and questionable utility. Methodological flaws that pervade the literature on drug withdrawal are discussed. It is argued that the conclusion of the majority of these studies that withdrawal contributes to significant deterioration is not warranted because of frequently repeated design errors. (5 p ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
776.
M De Vincenzi F Castriotta S Di Folco A Dracos M Magliola R Mattei I Purificato A Stacchini P Stacchini V Silano 《Food Additives & Contaminants》1987,4(2):161-218
In this paper we present a compilation of quantitative literature data on volatile compounds in 15 food items including some brandies, meats, oils as well as vegetables, vinegar and potatoes. Levels of the volatile compounds identified (approximately 900) in this group of food items are generally in the ppm range. Carboxylic acids were present in much higher levels in plum brandy, vinegar, lamb and mutton (heated), whereas alcohols, esters and carbonyls aldehydes are particularly abundant in brandy. 相似文献
777.
778.
Spörhase Stefanie Brombach Falk Marian Eckhardt Felix Krause Tim Markus Detlev Küstner Bernd Walch Otto 《Forschung im Ingenieurwesen》2023,87(2):605-616
Forschung im Ingenieurwesen - Der Einsatz von elektrischen Geräten in explosionsgefährdeten Bereichen erfordert besondere Schutzmaßnahmen, um eine Zündung der... 相似文献
779.
A novel design methodology for extended continuous class-F power amplifiers in wireless applications
Zarghami Sepehr Hayati Mohsen Kazimierczuk Marian K. Sekiya Hiroo 《Wireless Networks》2021,27(6):3947-3968
Wireless Networks - In this paper, an extended continuous class-F power amplifier (PA) is investigated, designed, and fabricated. The new auxiliary parameter $$left(beta +alpha... 相似文献
780.
Fitzgibbon Marian L.; Stolley Melinda R.; Avellone Mary E.; Sugerman Sharon; Chavez Noel 《Canadian Metallurgical Quarterly》1996,15(6):413
The authors explored changes in dietary behavior, nutrition knowledge, and parental support among inner-city, low-income, Hispanic American families. Thirty-eight families were randomly assigned to receive a 12-week, culture-specific dietary intervention or be in a control group. Results showed that parental support was related to changes in diet, nutrition knowledge, and attendance for both mothers and children. Dietary behavior changes (e.g., reduction in dietary fat) were seen only in the treatment group. Distribution of health-related pamphlets to the control group may have promoted cognitive changes (e.g., increased nutrition knowledge) seen in this low-literacy sample. Further research is needed to document behavioral changes after ethnic-specific interventions and the maintenance of those changes over time. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献