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排序方式: 共有244条查询结果,搜索用时 31 毫秒
31.
A gradient method for the optimal control of systems described by integral equations is presented. 相似文献
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Peter B. Kelly Raymond Reiser Donald W. Hood 《Journal of the American Oil Chemists' Society》1958,35(5):189-192
It appears that young mullet make excellent experimental fish for dietary studies. They are hardy, easily caught, resistant
to disease, and take well to aquaria conditions. Of particular interest, they may be fed synthetic food and they resist changes
in salinity well. These experiments indicate that, on a fatfree diet, the mullet does not synthesize the large amounts of
polyunsaturated fatty acids normally found in its body fat. However the mullet, like land animals, can apparently convert
dienoic acid from cottonseed oil into small amounts of tetraenoic, pentaenoic, and hexaenoic acids. Unlike land animals, the
mullet appears to be capable of the conversion of linoleic acid to a trienoic acid. Finally, when fed a diet containing a
typical marine fat such as menhaden oil, the mullet stores it almost unchanged. 相似文献
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中国很多建筑师及业界专业人士对RMJM所知.是源自2008年北京奥运会投入使用的国家会议中心荣获多个国际奖项的深圳大学图书馆、饶富创意的苏州依云水岸及星岛仁恒或深圳半山‘兰溪谷等住宅项目或者是困RMJM的名称联想起世界其他地方的标志性建筑物,例如圣彼得堡的俄气城或可望列八吉尼斯世界纪录成为世界最倾斜建筑的阿布扎比首都门大厦。 相似文献
37.
Flexible and hydrophobic biobased films were obtained using zein esterified with methanol and para-toluene (p-toluene) sulfonic acid, cutin from tomato peels and ethanol. Esterification was confirmed by proton nuclear magnetic resonance and attenuated total reflectance–Fourier transform infrared spectroscopy (ATR-FTIR). Non-modified zein films were brittle and hydrophilic. ATR-FTIR demonstrated that zein esterification increased zein hydrophobicity. Without cutin, esterified zein films were hydrophobic but brittle. Addition of cutin yielded films that were flexible and hydrophobic, as demonstrated by contact angle measurements. Principal component analysis (PCA) of ATR-FTIR data showed that intensities at 3195 cm−1 and 3490 cm−1 were correlated to the relative hydrophobicity of zein films. PCA also showed that films of esterified zein and cutin were more hydrophobic than their counterparts (non-modified zein without cutin). Optical and scanning electron microscopy demonstrated that esterified zein was compatible with cutin and yielded cohesive films, which did not fracture upon bending. 相似文献
38.
Juan Carlos Gonzalez-Rosillo Moran Balaish Zachary D. Hood Neel Nadkarni Dimitrios Fraggedakis Kun Joong Kim Kaitlyn M. Mullin Reto Pfenninger Martin Z. Bazant Jennifer L. M. Rupp 《Advanced materials (Deerfield Beach, Fla.)》2020,32(9):1907465
Specialized hardware for neural networks requires materials with tunable symmetry, retention, and speed at low power consumption. The study proposes lithium titanates, originally developed as Li-ion battery anode materials, as promising candidates for memristive-based neuromorphic computing hardware. By using ex- and in operando spectroscopy to monitor the lithium filling and emptying of structural positions during electrochemical measurements, the study also investigates the controlled formation of a metallic phase (Li7Ti5O12) percolating through an insulating medium (Li4Ti5O12) with no volume changes under voltage bias, thereby controlling the spatially averaged conductivity of the film device. A theoretical model to explain the observed hysteretic switching behavior based on electrochemical nonequilibrium thermodynamics is presented, in which the metal-insulator transition results from electrically driven phase separation of Li4Ti5O12 and Li7Ti5O12. Ability of highly lithiated phase of Li7Ti5O12 for Deep Neural Network applications is reported, given the large retentions and symmetry, and opportunity for the low lithiated phase of Li4Ti5O12 toward Spiking Neural Network applications, due to the shorter retention and large resistance changes. The findings pave the way for lithium oxides to enable thin-film memristive devices with adjustable symmetry and retention. 相似文献
39.
S. W. Mahajan ;J. Hart ;J. Hood ;A. Everheart ;M. L. Redigolo ;D. S. Koktysh ;E. A. Payzant ;J. H. Dickerson 《中国稀土学报(英文版)》2008,26(2):131-135
Anisotropic structures, nanoneedles, and nanospindles of rare earth hydroxychloride (RE(OH)2Cl) and oxychloride (REOCl) (rare earth=Eu and Tb) were synthesized. The rare earth hydroxychloride nanostructures were formed via a thermally assisted hydrolysis of the rare-earth sesquioxide nanocrystals. The morphological evolution of the nanostructures was studied using high-resolution transmission electron microscopy and scanning electron microscopy, while the structural evolution was investigated using X-ray diffraction techniques. The thermal stability of the rare earth hydroxychlorides was investigated using thermogravimetric analysis. The rare earth oxychloride nanospindles were synthesized via a simple heat-treatment of rare earth hydroxychloride nanospindles. 相似文献
40.
Stephen J. Dain John W. Hood Stewart Montano Constantine Arali 《Color research and application》1998,23(1):4-17
The accurate identification of cyanosis depends on a number of factors including the quality and quantity of the lighting used. Requirements framed in terms of permissible limits on correlated colour temperature and colour-rendering indices worked satisfactorily for many years. However, the demise of halophosphate fluorescent lamp technology and its replacement with triphosphor technology has led to a need to reevaluate the former methods and acceptance criteria. The experimental methods of assessing previous light sources were long and involved. It is impractical to replicate them as each new light source or new lighting technology is developed. There is a need, therefore, for a colorimetric method of assessing light sources for this purpose. In this study, the spectral reflectance characteristics of blood with oxygen saturation levels from 95.6–0.7% are used to calculate colour changes with respect to a reference illuminant and correlated with the results of an extensive study, some years ago, of the influence of light sources in the detection of cyanosis. The results lead to a method of evaluation with a single value criterion for acceptability. The method lends itself to simple modeling techniques for phosphor mixtures and should simplify the design of appropriate fluorescent tube sources for clinical visual evaluation of cyanosis. © 1998 John Wiley & Sons, Inc. Col Res Appl, 23, 4–17, 1998. 相似文献