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Differentiation of Barley Genotypes with High Phosphorus Efficiency under Low Phosphorus Stress 被引量:2
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作者 杨涛 何金宝 +3 位作者 曾亚文 普晓英 杨树明 杜娟 《Agricultural Science & Technology》 CAS 2013年第11期1615-1619,共5页
[Objective] This study aimed to investigate differences in phosphorus effi-ciency between two-rowed barley and multiple-rowed barley and differences in phos-phorus efficiency among various agronomic traits, and to exp... [Objective] This study aimed to investigate differences in phosphorus effi-ciency between two-rowed barley and multiple-rowed barley and differences in phos-phorus efficiency among various agronomic traits, and to explore the relationship be-tween agronomic traits and row type with phosphorus efficiency. [Method] Under available phosphorus mass fractions of 1.32 and 36.6 mg/kg, 172 barley varieties, including 79 two-rowed foreign barley, 22 multiple-rowed foreign barley, 58 two-rowed Chinese barley and 13 multiple-rowed Chinese barley, were selected to com-pare differences in phosphorus efficiency-related agronomic traits. Plant height, spike length, number of unfil ed grains, number of unfil ed grains, main panicle weight, to-tal panicle weight, total stem weight, weight of aerial part and heading stage were surveyed for statistical analysis. [Result] The results showed that, various agronomic traits were larger under fertilization condition than under non-fertilization condition ex-cept number of unfil ed grains and heading stage. Plant high, spike length, weight of aerial part and heading stage varied greatly under non-fertilization condition; number of fil ed grains, number of unfil ed grains and total stem weight varied greatly under fertilization condition. In two-rowed barley, plant height and number of fil ed grains of Chinese varieties were higher than those of foreign varieties, while other agronomic traits such as spike length, number of unfil ed grains, main panicle weight, total panicle weight, total stem weight, weight of aerial part and heading stage of foreign varieties were higher than those of Chinese varieties. Spike length and weight of aerial part in multiple-rowed and two-rowed foreign barley were higher than those in Chinese barley. In multiple-rowed barley, plant height, number of unfil ed grains, total panicle weight and total stem weight of foreign varieties were higher under non-fer-tilization condition and lower under fertilization condition compared with those of Chi-nese varieties; number of fil ed grains, main panicle weight and heading stage of foreign varieties were lower under non-fertilization condition and higher under fertil-ization condition compared with those of Chinese varieties. [Conclusion] Heading stage, number of fil ed grains, number of unfil ed grains and total stem weight are more sensitive to phosphorus efficiency. Multiple-rowed barley is more sensitive to phosphorus efficiency than two-rowed barley. 展开更多
关键词 Low phosphorus stress BARLEY High phosphorus efficiency GENOTYPE Agronomic traits
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谈日语中名词的声调
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作者 戴玉金 《龙岩师专学报》 2002年第1期83-84,共2页
日语的声调为高低型,一个假名代表一个音节。其中,名词按音节数排列起来,可分成平板式和起伏式,当名词后接助词、助动词时,原声调若是平板式时,则句节平接;若为起伏式,后接的助词、助动词均要低读。
关键词 平板式 起伏式 句节平接 低读 日语 名词 声调 高低型 假名
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Development and application of an efficient gas extraction model for low-rank high-gas coal beds 被引量:28
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作者 Baiquan Lin 《International Journal of Coal Science & Technology》 EI 2015年第1期76-83,共8页
To promote gas extraction in low-rank high-gas coal beds, the pore structure characteristics of the coal and their effect on gas desorption were studied. The results show that micropores are relatively rare in low-ran... To promote gas extraction in low-rank high-gas coal beds, the pore structure characteristics of the coal and their effect on gas desorption were studied. The results show that micropores are relatively rare in low-rank coal; mesopores are usually semi-open and inkpot-shaped whereas macropores are usually slit-shaped. Gas desorption is relatively easy at high- pressure stages, whereas it is difficult at low-pressure stages because of the 'bottleneck effect' of the semi-open inkpot-shaped mesopores. A 'two-three-two' gas extraction model was established following experimental analysis and engineering practice applied in the Binchang mining area. In this model, gas extraction is divided into three periods: a planning period, a transitional period and a production period. In each period, surface extraction and underground extraction are performed simultaneously, and pressure-relief extraction and conventional extraction are coupled to each other. After applying this model, the gas extraction rate rose to 78.8 %. 展开更多
关键词 Low-rank coal Pore structure Gas extraction Inkpot-shaped pore
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3D numerical simulation of high pressure squeezing process with revised Drucker-Prager/Cap model
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作者 Zhang Qingdong Ni Changjiang +2 位作者 Jing Tao Wu Junjiao Makino Hiroyasu 《Journal of Southeast University(English Edition)》 EI CAS 2017年第4期473-477,共5页
In order to investigate the sand mold strength after the aeration sand filling-high pressure squeeze moldingprocess,a tree-dimentional(3D)numerical simulation was introduced.The commercial finite element method(FEM)so... In order to investigate the sand mold strength after the aeration sand filling-high pressure squeeze moldingprocess,a tree-dimentional(3D)numerical simulation was introduced.The commercial finite element method(FEM)software ABAQUScombined with a revised Drucker-Prager/Cap model was used to simulate the squeeze compaction process.Additionally,the sand bulk density after the aeration sand filling process was tested by a specially designed experiment,which divided the whole sand bulk in the molding chamber into5x9regions and it was used as the input to simulate the squeeze process.During the simulation process,the uniform modeling simulation and the patition modeling simulation methods were used a d the3D numercal simulation results were compared with correlative benchmark testings.From the3D numerica simulation results,it can be concluded that the uniform sand bulk density distribution can obtain a high quality sandmold and the revised Drncker-Pager/Cap model is suitable for handling the situation with the complex paaern.The3D numerical simulation results can predict well the sand mold strength distribution and can be used as guidelines for the production practice. 展开更多
关键词 green sand aeration sand filling-high pressure squeeze molding revised Drucker-Prager/Cap model numerical simulation
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Invariant Measures and Asymptotic Gaussian Bounds for Normal Forms of Stochastic Climate Model
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作者 Yuan YUAN Andrew J. MAJDA 《Chinese Annals of Mathematics,Series B》 SCIE CSCD 2011年第3期343-368,共26页
The systematic development of reduced low-dimensional stochastic climate models from observations or comprehensive high dimensional climate models is an important topic for atmospheric low-frequency variability,climat... The systematic development of reduced low-dimensional stochastic climate models from observations or comprehensive high dimensional climate models is an important topic for atmospheric low-frequency variability,climate sensitivity,and improved extended range forecasting.Recently,techniques from applied mathematics have been utilized to systematically derive normal forms for reduced stochastic climate models for low-frequency variables.It was shown that dyad and multiplicative triad interactions combine with the climatological linear operator interactions to produce a normal form with both strong nonlinear cubic dissipation and Correlated Additive and Multiplicative(CAM) stochastic noise.The probability distribution functions(PDFs) of low frequency climate variables exhibit small but significant departure from Gaussianity but have asymptotic tails which decay at most like a Gaussian.Here,rigorous upper bounds with Gaussian decay are proved for the invariant measure of general normal form stochastic models.Asymptotic Gaussian lower bounds are also established under suitable hypotheses. 展开更多
关键词 Reduced stochastic climate model Invariant measure Fokker-Planck equation Comparison principle Global estimates of probability density function
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