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FENG Guo liang 《保鲜与加工》2001,1(4):31-33
材料和方法 1.1试验材料 荔枝果实采自武鸣县府城镇大同村陶蓬德果场,品种为新丰黑叶,果实成熟度为 9成半;龙眼果实采自武鸣县城东镇大同村蒙桂辅果场,品种为石硖、储良,果实成熟度分别为 8成半和 8成。 1.2采前处理 荔枝采收前即 2000年 6月 15日和 6月 28日分别 相似文献
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As a standardized formal language, the SDL has widely been used in the software development. In order to extend its application field, it has been explored to use in hardware design.This paper gives a logical gate circuit-and gate as an example to explain the method of applying SDL to describe and simulate/validate the hardware characters by the SDT tool. The various logic circuits or digital circuits may be made to the SDL packages because the SDL supports the object oriented technology. These packages can be directly invoked in the design of the complex digital system, so it is possible to describe and simulate/validate the complex digital system.The experiment has proved that the application of SDL for hardware design is feasible and rather convenient. 相似文献
54.
In chemistry and many related fields, electronegativity (EN) is an important fundamental concept and its scale is a useful physcochemical parameter. Here, calculations of both ionization potentials and electron affinities are extended toward 107 elements and done by density functional theory at the local density approximation(LDA) level and the LDB level, i.e., the local density approximation level with further non-local corrections for exchange and correlation included self-consistently as well as the modified Slater transition-state method. The definite-differentiation method is employed into calculations of the electronegativity scale and the related parameters of 107 elements with very good results due to the consideration of relativistic effects. The calculation presented is to examine both the LDA and LDB approximations in calculations for the ionization potential and electron affinity of the elements with an improved or modified Slater transition-state method, and relativistic effects have also been taken into account for 107 elements compared with 103, 86 or less in the previous report under a spin polarized density function theory with some approximations to the exchange-correlation function. The calculation results for the various quantities represent an obviously improvement over some previous calculations. It is shown that the results calculated by the extended technique and the improved Slater transition-state method in general agree well with experimental values presented by Pearson, and are better than the reported values in many previous literatures. The developed new electronegativity scale will widely be applicable in many fields such as molecular structural parameterization expression, chemobiological activity optimization prediction, structure-activity quantitation modeling, functional chemical adaptization designing, and so on. 相似文献
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The research of neural network has been maturated both in theory and practical application since 1980's, and also been employed into the prediction and analysis of nonlinear time series signal in the field of signal process system. Concerning with the problem of time series signal prediction based on traditional neural network, such as black box, poor accuracy, and facing the shortage of post knowledge, this paper presents a different neural network prediction model from the traditional ones, based on intelligent neural cell model and employing the iterative prediction method. Through the example on stock price prediction, the prediction accuracy and practical value are proved. 相似文献
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The Extended Kalman Filter Data Fusion Algorithm Based on Discrete Stationary Wavelet Transformation
It is difficult to establish precise mathematical model in extended Kalman filter data fusion algorithm for GPS/ DR integrated vehicle navigation system, an improved extended Kalman filter data fusion algorithm is put forward based on Discrete stationary wavelet transformation. The simulation results show that the algorithm is better than the extended Kalman filter data fusion algorithm, and is available for GPS/DR integrated vehicle navigation system. 相似文献
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以 4个辣椒品种为材料 ,探讨飞船搭载对辣椒种子发芽力、植株生长特性、果实性状的影响。结果表明 :飞船搭载对辣椒种子的发芽率和发芽势有一定的影响 ,这种影响随材料而异 ;搭载种子平均初花期较对照提早 0 2~ 3 2d ,且株间变异增加 ,植株有矮化的趋势 ;第 1花序节位也呈降低态势 ,结果能力有所提高 ,但果实长度、直径和平均单果重呈下降趋势 相似文献
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利用盆栽试验研究了几种人工合成磷源在轻粘质潮土根际和本体土壤中的形态转化及配施不同形态氮肥对其形态转化的影响 ,结果表明 ,作物耗竭引起根际所有形态无机磷不同程度的下降。施入土壤的DCP(CaHPO4 ·2H2 O)、OCP(Ca8(PO4 ) 6 )、Al P(AlPO4 ·nH2 O)等大部分转化为其它形态无机磷 ,而Fe P(FePO4 ·nH2 O)和FA(Ca10 (PO4 ) 6 F2 )大部分以自身形态存在 ,尤其是FA很少向其它形态转化 ,根际条件促进了它们向其它无机磷形态的转化。Al P和FA等的形态转化明显受氮肥形态的影响 ,Al P配施NO- 3 N下 ,绝大部分转化为磷灰石 ,NH 4 N配施下促进了FA向其它形态的转化 ,在所有的磷源处理中 ,根际和本体磷酸铁都有显著地增加 ,NH 4 N和CO(NH2 ) 2 处理下存在磷酸铁的根际累积 ;其次是磷酸二钙和磷酸铝也有明显地增加 ,二者存在根际的亏缺。不同磷源的形态转化规律与其有效性大小相一致。 相似文献