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91.
Ju H. Choi Alfred Margaryan Ashot Margaryan Frank G. Shi 《Journal of Materials Science》2008,43(3):1109-1113
The dependence of thermo-mechanical, and mechanical properties on various rare earth dopants (RE) including Nd2O3, Er2O3, and Yb2O3 in 0.4MgF2-0.4BaF2-0.1Ba(PO3)2-0.1Al(PO3)3 glasses (MBBA system) is systematically investigated. MBBA system doped with RE dopants presented the potential application
in the field of communication and high power layer system in the previous reports. In this work, it is found that the density
of the doped glass increases with an increasing of RE concentration, which could be understood in terms of cationic field
strength (CFS) effect. The Knoop hardness is found to decrease with the loading time and dopant concentration due to the indentation
size effect (ISE) effect. The observed decrease of thermal expansion coefficient and the increase of glass transition temperature
T
g with increasing dopant concentration are elucidated in terms of the increasing number of strong covalent bonds with increasing
RE dopant concentration. Those results will be of paramount importance before designing optical devices. 相似文献
92.
Alfred Clark 《Catalysis Reviews》1970,3(1):145-173
There are at least three heterogeneous catalyst systems of interest for low-pressure polymerization of olefins to high polymers: 相似文献
93.
94.
Teachers of introductory courses in psychology and those who wrote the textbooks for the courses at the start of the 20th century represented the new psychology that replaced the old psychology of mental philosophy. Teachers and texts presented psychology as a natural science of the mind and mental processes, described its methods, and suggested its potential applications to practical concerns. Textbooks and teachers varied in their approaches to psychology, their priorities among its methods, and their emphases on applying psychology. The introductory course in psychology accurately reflected the state of the discipline at the turn of the century. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
95.
Analysis‐preserving video microscopy compression via correlation and mathematical morphology 下载免费PDF全文
Chong Shao Alfred Zhong Jeremy Cribb Lukas D. Osborne E. Timothy O'Brien III Richard Superfine Ketan Mayer‐Patel Russell M. Taylor II 《Microscopy research and technique》2015,78(12):1055-1061
The large amount video data produced by multi‐channel, high‐resolution microscopy system drives the need for a new high‐performance domain‐specific video compression technique. We describe a novel compression method for video microscopy data. The method is based on Pearson's correlation and mathematical morphology. The method makes use of the point‐spread function (PSF) in the microscopy video acquisition phase. We compare our method to other lossless compression methods and to lossy JPEG, JPEG2000, and H.264 compression for various kinds of video microscopy data including fluorescence video and brightfield video. We find that for certain data sets, the new method compresses much better than lossless compression with no impact on analysis results. It achieved a best compressed size of 0.77% of the original size, 25× smaller than the best lossless technique (which yields 20% for the same video). The compressed size scales with the video's scientific data content. Further testing showed that existing lossy algorithms greatly impacted data analysis at similar compression sizes. Microsc. Res. Tech. 78:1055–1061, 2015. © 2015 Wiley Periodicals, Inc. 相似文献
96.
97.
Alfred Hesener 《电子与电脑》2010,(9):49-52
电池没电,和经常需要充电,哪一种较恼人?现今手机(特别是智能型手机)在世界各地迅速普及,一周七天,一天二十四小时,人们随时都保持着联机的状态。消费者似乎总是没完没了地进行语音通话、收发电子邮件、发送简讯和上网, 相似文献
98.
András Tompos József L. Margitfalvi Lajos Végvári Alfred Hagemeyer Tony Volpe C. J. Brooks 《Topics in Catalysis》2010,53(1-2):100-107
This paper reports the combination of Holographic Mapping (HM) and Artificial Neural Networks (ANNs) in order to provide a benchmark visualization of a multi-dimensional space in two-dimensional forms. In this approach each matrix point in HM represents virtual catalytic data generated by means of ANNs in order to visualize the given multi-dimensional experimental space. A 12-dimensional experimental space related to the composition of catalysts designed for the water gas shift reaction (WGSR) from 12 possible components supported on ZrO2 is visualized. Catalytic data obtained in an earlier combinatorial screening process at 300 °C were used for training of the ANNs. The results show that the visualization of large experimental spaces having more than half a million virtual experimental points can be accomplished. The analysis of synergistic effects between different components revealed that the key components of water gas shift catalysts at 300 °C were Pt, Fe, Eu and V, while Co, Ru, Sb, Ge and Mo had a pronounced negative effect on the activity. 相似文献
99.
John O Offem Emmanuel O Egbe Alfred I Onen 《Journal of the science of food and agriculture》1993,62(2):147-155
The cotyledons of two varieties of germinating groundnut seeds (Runner and Bunch) were analysed periodically for their lipid content and fatty acid composition over a period of 132 h. The lipid content decreased drastically during germination. More drastic changes in lipid constituents were observed for light-grown seedlings than for dark-grown ones. In general, the non-polar lipids (NPL) were metabolised faster than the polar ones (P > 0.05) especially in those seeds grown in the dark. The rate of decrease in NPL content almost paralleled that of increase in glycolipid (GL) content. Triacyl glycerol content decreased noticeably during germination while other NPL tended to increase. Among the GL, sterylglucoside increased rapidly during early germination under darkness, only to decrease steadily thereafter. A converse effect was observed for acyl sterylglucoside which, in the dark, decreased rapidly at early germination only to increase equally rapidly later on. Among the phospholipids (PL), only phosphatidic acid showed a marked increase during germination, under both growth conditions, while others tended to decrease in varying degrees. The changing patterns of GL and PL during germination seem to follow the pattern of the formation of photosynthetic tissues and the metabolic conversion of PL. The major fatty acids of the three lipid groups, which more or less decreased or increased in varying degrees with germination in light-grown seeds were oleic, linoleic, palmitic, stearic, arachidic and lignoceric acids in decreasing order of prominence at early germination. 相似文献
100.
For a polydisperse nanoparticle ensemble the evaluation of time-resolved laser-induced incandescence (LII) measurements yields a weighted average value for the primary nanoparticle size. Although this value is sufficient for narrow size distributions, a comprehensive characterization of a particle-evolution process requires the reconstruction of the size distribution. An easy-to-use online approach is presented to evaluate the LII signal regarding higher moments of the distribution. One advantage of this approach is that the size distribution results in a deceleration of the LII signal decay with time after the laser pulse. Therefore LII signal-decay curves are evaluated in two different time intervals after the laser pulse, providing information about the desired distribution parameters that has been tested successfully with experimental curves taken in different soot-formation processes. 相似文献