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Solar Radiation Interception, Dry Matter Production and Yield among Different Plant densities of Arachis spp. in Ibadan, Nigeria

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Agricultural Sciences 2014年第10期5卷 864-874页

作者： Kolapo O. Oluwasemire George O. Odugbenro College of Resources and Environment Northeast Agricultural University Harbin China Department of Agronomy Faculty of Agriculture and Forestry University of Ibadan Ibadan Nigeria

The production of grain legumes is becoming a popular practice in the humid south western Nigeria. Apart from the decreasing trends observed in rainfall amount and duration as a result of climate change, solar radiation interception also constitutes a limitation to crop production because of persistent cloud cover. A trial was conducted at the University of Ibadan experimental site to determine the effect of different plant densities of Arachis spp. on solar radiation interception, dry matter production and yield in Ibadan, Nigeria with the aim of ascertaining the best practice for groundnut production in the zone. The treatments were three plant spacings (60 cm×20 cm,75 cm×20 cmand75 cm×40 cm), and three Arachis varieties (Samnut 10, Samnut 21 and Pintoi) arranged in a split plot, randomized complete block design with Arachis varieties as the main plot while plant densities formed the subplot and replicated three times. Growth parameters (number of leaves, dry leaf weight and dry stem weight) were measured at two weeks interval while yield parameters (number of pods, dry pod weight, dry seed weight and total dry matter) were determined at harvest. Intercepted radiation by plants (PAR) was also taken along with the growth parameters. The highest light interception from 42 - 105 days after planting (DAP) among the Arachis spp. was recorded by Samnut 10, while at 42 - 87 DAP, plant density of75 cm×20 cmhad the highest light interception. Dry matter production increased with light interception and was highest at 105 DAP when light interception was between 55% and 60% for all Arachis varieties and all plant densities. In terms of pod weight and grain yield, Samnut 10 performed better than Samnut 21 and also recorded the highest Radiation Use Efficiency (RUE) for pod, seed and total dry matter. However, Arachis pintoi, a sterile and forage plant with slower growth rate served as a cover crop capable of replenishing soil nutrients and physical properties.

关键词： Radiation Use Efficiency Arachis spp. Plant densities Solar Radiation Interception

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不同投放密度的浮萍对水体氮磷去除效果的初步研究

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江西农业学报 2010年第11期22卷 161-163页

作者：周雄飞史巍吴晶柏彦超周明耀钱晓晴扬州大学环境科学与工程学院江苏扬州225009 扬州大学水利科学与工程学院江苏扬州225009

以扬州市郊的少根紫萍、稀脉浮萍为试验材料,研究不同浮萍覆盖面积对营养液中总氮、总磷的去除效果。结果表明,不同投放密度与TN、TP的去除率有一定的线性关系,随着投放量的增加,浮萍对营养液中TN、TP的总去除率提高。单位投放密度的TN... 详细信息

以扬州市郊的少根紫萍、稀脉浮萍为试验材料,研究不同浮萍覆盖面积对营养液中总氮、总磷的去除效果。结果表明,不同投放密度与TN、TP的去除率有一定的线性关系,随着投放量的增加,浮萍对营养液中TN、TP的总去除率提高。单位投放密度的TN、TP去除率(去除率/投放密度)随着投放密度的增加而下降。

关键词：投放密度浮萍水体氮磷去除效果初步研究 densities of Different Water Body Nitrogen and Phosphorus 总去除率营养液线性关系试验材料少根紫萍覆盖面积投放量总磷总氮扬州

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Global optimum of microstructure parameters in the CMWP line-profile-analysis method by combining Marquardt-Levenberg and Monte-Carlo procedures

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Journal of Materials Science & Technology 2019年第7期35卷 1508-1514页

作者： Gabor Ribarik Bertalan Joni Tamas Ungar Department of Materials Physics Edtvos University BudapestPO Box 32H-15J8Hungary School of Materials The University of ManchesterM139PLUK

Line profile analysis of X-ray and neutron diffraction patterns is a powerful tool for determining the microstructure of crystalline materials. The Convolutional-Multiple-Whole-Profile (CMWP) procedure is based on physical profile functions for dislocations, domain size, stacking faults and twin boundaries. Order dependence, strain anisotropy, hkl dependent broadening of planar defects and peak shape are used to separate the effect of different lattice defect types. The Marquardt-Levenberg (ML) numerical optimiza-tion procedure has been used successfully to determine crystal defect types and densities. However, in more complex cases like hexagonal materials or multiple phases the ML procedure alone reveals uncer-tainties. In a new approach the ML and a Monte-Carlo statistical method are combined in an alternative manner. The new CMWP procedure eliminates uncertainties and provides globally optimized parameters.

关键词： X-ray line profile analysis Neutron line profile analysis CMWP Global optimum Dislocation densities Grain size Planar defects Monte-Carlo method

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A Laboratory Study of the Effect of Temperature on densities and Viscosities of Binary and Ternary Blends of Soybean Oil, Soy Biodiesel and Petroleum Diesel Oil

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Advances in Chemical Engineering and Science 2012年第4期2卷 444-452页

作者： Oluwafunmilayo A. Aworanti Samuel E. Agarry Ayobami O. Ajani Biochemical Engineering and Biotechnology Research Laboratory Department of Chemical Engineering Ladoke Akintola University of Technology Ogbomoso Nigeria

The depletion of world petroleum reserves and the increased environmental concerns have stimulated the search for alternative sources for petroleum based fuel. The possibility of using vegetable oils as fuel has been recognized, however, due to its high viscosities and low volatilities makes it inefficient for most combustion engines and thus the need to get them chemically altered or transesterified to obtain fatty alkyl esters of the oil (biodiesel). In this study, binary and ternary blends of biodiesel were produced and the effect of temperature on their viscosity and density was investigated. Biodiesel was produced from soybean oil by transesterification of the oil with methanol using potassium hydroxide as a catalyst at a temperature of 60℃ in a batch reactor. Binary and ternary blends of the soy-biodiesel were prepared with soy bean oil and petroleum diesel fuel, respectively. Viscosities and densities of the binary and ternary blends were measured at different temperatures of 20℃ to 90℃ as to determine the effect of temperature on viscosities and densities of the blends. The properties of the soy-biodiesel produced were compared with ASTM standard and found to be within the limits. The results show that the viscosities and densities of both the binary and ternary blends are temperature dependent. The viscosities of binary and ternary blends decreased nonlinearly with temperature, while their densities decreased linearly with temperature. The variation of temperature with viscosity and density of the blends was correlated and the polynomial equation offered the best correlation between temperature and viscosity, while linear equation gave the best correlation between temperature and density. In conclusion, the efficiency of binary and ternary blends of biodiesel in combustion engines is dependent on the viscosity and density of the blends which are invariably temperature dependent.

关键词： densities Viscosities Batch Reactor Diesel Fuel Soy-Biodiesel Vegetable Oil

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Asymptotic behavior for sums of non-identically distributed random variables

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Applied Mathematics(A Journal of Chinese Universities) 2019年第1期34卷 45-54页

作者： YU Chang-jun CHENG Dong-ya School of Sciences Nantong University School of Mathematical Sciences Soochow University The Statistics and Operations Research Department the University of North Carolina at Chapel Hill

For any given positive integer m, let X_i, 1 ≤ i ≤ m be m independent random variables with distributions F_i, 1 ≤ i ≤ m. When all the summands are nonnegative and at least one of them is heavy-tailed, we prove that the lower limit of the ratio ■equals 1 as x →∞. When the summands are real-valued, we also obtain some asymptotic results for the tail probability of the sums. Besides, a local version as well as a density version of the above results is also presented.

关键词： lower limits upper limits heavy-tailed distributions local distributions densities

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