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1.
Silicon - Feeling prone to stress differs with plant production stage, water scarcity near commencement of grain filling phase has a significant reduced grain yield through fewer endosperm and sink...  相似文献   
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Journal of Mechanical Science and Technology - Presently, countries are trying to increase their energy efficiency. Therefore, the operating temperatures of very high temperature reactor (VHTR) and...  相似文献   
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Silicon - The present study evaluated the effect of silicon (Si) seed priming and sulfur (S) foliar spray on drought tolerance of two contrasting maize hybrids viz. drought tolerant Hi-Corn 11 and...  相似文献   
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The National Institute of Standards and Technology (NIST) conducted an extensive investigation of the collapse of World Trade Center towers (WTC 1 and WTC 2) and the WTC 7 building. This paper describes the component, subsystem, and global analyses performed for the reconstruction of the structural response of WTC buildings 1, 2, and 7 to impact and fire damage. To illustrate the component and subsystem analyses, the approach taken for simulating the performance of concrete slabs and shear stud connectors in composite floors subject to fire conditions are presented, as well as steel floor framing connections for beams and girders. The development of the global models from the component and subsystem analyses is briefly described, including the sets of input data used to bound the probable conditions of impact and fire damage. The final analysis results that were used to develop the probable collapse hypotheses, and a comparison of the results against observed events, are presented for each building. A review of research activities focused on improving understanding of structural system response to multi-floor fires following the WTC disaster is also provided.  相似文献   
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A new, simple and reliable empirical correlation for predicting the viscosities of heavy petroleum fractions is proposed, applicable to fractions with mid-boiling points from 80 to 550°C over a wide range of viscosities (0.4 to 260 mm2 s−1) and measurement temperatures (40 to 200°C). This correlation showed better accuracy in the prediction of heavy petroleum fraction viscosities than that of the most accurate and much more complicated predictive methods in the literature, since it gave an overall average absolute deviation of 6.5% when tested on 296 data for medium and heavy petroleum fractions.  相似文献   
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Thermal decomposition of the basic components of dried biomass (cellulose, lignin, wood) is studied in inert atmosphere. Glucose is studied for comparison. The experiments are performed in an alumina porous bed reactor heated at temperatures between 600 and 1000°C. Flash pyrolysis (heating rate 250°C/s) allows the production of a medium heating value synthetic gas with gas phase conversion thermal efficiency of up to 95 percent. The weight percent of carbon gasified during the pyrolysis reaches 90 percent for cellulose and 70 percent for wood. Light hydrocarbons (CH4, C2H4, C2H2, C2H6) provide about 50 percent of the energy recovered in the gas. Ethylene represents 5 percent (vol) of the pyrolysis gas. The overall ethylene and acetylene yield is markedly increased at high temperatures for short gas residence times. The pyrolysis reactions are endothermic. The total amount of energy required for pyrolysing wood at 850°C roughly corresponds to 20 percent of its heating value.  相似文献   
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