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1.
Wheat endosperm texture (hardness) largely determines end-product suitability. Since its development 25 years ago, the single kernel classification system (SKCS, a mechanical instrument that measures, among other properties, the force imparted on a kernel during crushing) has been used in breeding programs to differentiate soft wheats from hard wheats. Nominally, these have a soft to hard SKCS hardness index (HI) range of 25–75 (dimensionless units). However, in recent years, breeders have developed extremely soft (‘Super Soft’) lines having SKCS HI < 0. Until now, these very low SKCS HIs have not been corroborated with traditional methodologies that characterize mechanical strength. Herein, we report on the relationships between SKCS HI and three compressive strength properties (maximum stress, Young's modulus, and work) in Super Soft wheat. With respective correlation coefficients of 0.76, 0.66, and 0.75, we have found that the relationships between SKCS HI and compressive strength agree with prior research involving ordinary soft and hard wheats. 相似文献
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[Objective]The energy productivity potential of Saccharum spontaneum L.germplasm resources as energy plants was discussed in this paper.[Method]The energy productivity potential of Saccharum spontaneum L.germplasm resources collected from the wild was assessed from the aspects of cellulose,semicellulose,lignin and crude ash contents and caloric value.[Result]The total content of cellulose and semicellulose ranged from 41.75%to 69.13%,the lignin content ranged from 2.16%to 11.75%,the crude ash content ranged from 4.79%to 9.34%and the caloric value ranged from 16.00 to 17.69 MJ/kg among the 30 Saccharum spontaneum L.germplasms.Compared to other plants,Saccharum spontaneum L.had higher contents of cellulose and semicellulose,a higher caloric value but lower contents of lignin and crude ash.[Conclusion]From the perspective of producing fuel ethanol with lignocellulose,Saccharum spontaneum L.has a great potential for development as an energy plant. 相似文献
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Optimising mineral nitrogen (N) use in crop production is inevitable target as mineral fertilisers reflect one of the highest inputs both in terms of economy and energy. The aim of the study was to compare the relationship between the rate of N fertiliser application and different measures of energy parameters exemplary data for spring-wheat in boreal climate condition in Estonia in 2006–2010. The effect of mineral N with rates 0, 40, 80, 120 and 160 kg N ha−1 was studied on the background of composted cow manure and without organic fertilisers. Univalent parameters, energy gain (EG) (energy output − energy input) and energy ratio (ER) (energy output/energy input) were calculated. To aggregate parameters with different units (ER and EG) we proposed two standardisation approaches for combined indices. ER maximisation gave both organic fertilisation background optimum N norms significantly lower than EG (p < 0.05) optimisation. Both the new combined indices gave optimum N norms in between the rate of ER an EG. Composted cow manure background did not affect mineral N optimisation significantly. We suggest optimisation of mineral N according to bi-dimensional parameters as they capture important features of production efficiency and are more objective using as advisory tool for sustainable production systems. 相似文献
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准确量化分析地气之间的物质和能量交换对于水资源管理和农业可持续发展是十分重要的。能量平衡闭合是评估观测数据准确性和分析地表能量平衡的一个重要的评价指数。本研究利用开路涡度相关系统和全要素自动气象站对华北平原典型冬小麦农田生态系统2013—2014年度的能量通量及常规气象要素进行了连续观测,分析了冬小麦农田各能量通量的日变化和年变化特征,计算冬小麦在4个生育时期(出苗期、越冬期、拔节期和灌浆期)的能量闭合和波文比。结果表明:在日尺度上,选取的4个生育时期净辐射和各能量分量的日变化趋势均为单峰二次曲线,净辐射、显热通量和潜热通量的峰值出现在12:00—13:00,土壤热通量的峰值出现在14:00—15:00。在年尺度上,净辐射和潜热通量的变化趋势较为一致,均在越冬期达到最低值114.51 W·m~(-2)和13.47 W·m~(-2),而在灌浆期达到最大值327.02 W·m~(-2)和116.56 W·m~(-2)。选取的4个生育时期的代表性观测日期能量闭合良好,能量闭合率分别为0.49、0.77、0.81和0.76。4个生育时期内波文比值日变化趋势均呈倒"U"型,出苗期波文比在14:00达到最大值2.12;越冬期、拔节期和灌浆期在10:00左右达到最大值,分别为1.48、0.31和0.58。本文的定量化结果可为华北平原农田生态系统水热通量等研究提供依据。 相似文献
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Tayyeb NazghelichiMortaza Aghbashlo Mohammad Hossein Kianmehr 《Computers and Electronics in Agriculture》2011,75(1):84-91
In this study, an integrated response surface methodology (RSM) and genetic algorithm (GA) are recommended for developing artificial neural networks (ANNs) with great chances to be an optimal one. A multi-layer feed forward (MLFF) ANN was applied to correlate the outputs (energy and exergy) to the four exogenous inputs (drying time, drying air temperature, carrot cubes size, and bed depth). The RSM was used to build the relationship between the input parameters and output responses, and used as the fitness function to measure the fitness value of the GA approach. In the relationship building, five variables were used (number of neurons, momentum coefficient and step size in the hidden layer, number of epochs and number of training times). A polynomial model was developed from training results to mean square error (MSE) of 50 developed ANNs to generate 3D response surfaces and contour plots. Finally, GA was applied to find the optimal topology of ANN. The ANN topology had minimum MSE when the number of neurons in the hidden layer, momentum coefficient, step size, number of training epochs and training times were 28, 0.66, 0.35, 2877 and 3, respectively. The energy and exergy of carrot cubes during fluidized bed drying were predicted with R2 values of greater than 0.97 using optimal ANN topology. 相似文献
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能源消费、环境保护与经济增长是一个有机的整体。笔者以山东省为例,利用灰色关联分析分别进行产业结构对经济增长、工业发展对能源消费和环境污染的综合分析,并提出符合山东省基本情况的多项发展决策机制。 相似文献
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