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101.
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
102.
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
103.
Durch Kombination eines Plasmaspektrometers (ICP) mit einer neuen Apparatur zur elektrothermischen Verdampfung konnte der Gehalt an metallischem Calcium in niedrig legiertem, calciumbehandeltem Stahl bestimmt werden. Die kontrollierte Erwärmung von Stahlspänen auf 2 000°C führt zur vollständigen Verdampfung des elementaren Calciums, während das chemisch gebundene Calcium bei dieser Temperatur nicht verdampft. Das verdampfte Calcium wurde mit Argon in das Plasmaspektrometer transportiert, und das erzeugte Emissionsspektrum wurde zur quantitativen Auswertung genutzt. 相似文献
104.
105.
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
106.
We monetize the cost for moving to a culturally different location. We combine administrative social security panel data with a proxy for cultural difference based on historical dialect dissimilarity between German counties. Conditional on geographic distance and pre‐migration wage profiles, we find that migrants demand a (indexed with respect to local rents) wage premium of about 1 (1.5) per cent for overcoming one standard deviation in cultural dissimilarity. The effect is driven by males and those who earn above average occupational wages before migration, and more pronounced for geographically short moves. 相似文献
107.
Analysis‐preserving video microscopy compression via correlation and mathematical morphology
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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
108.
109.
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
110.
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