A Preliminary Study on Dynamics and Models of N,P,K Absorption for High-Yield Cotton

The field experiments were carried out to investigate the dynamics and models of N, P and K absorption for the cotton plants with a lint of 3 000 kg ha-1 in Xinjiang. The main results were as follows: The contents of N, P2O5, K2O in cotton leaves, stems, squares and bolls decreased obviously with the time over the whole growth duration and the falling extent was greater in high-yield cotton than in CK. Contents of N in leaves, squares and bolls, in particular in the leaves of fruit-bearing shoot was higher in high-yield cotton than in CK. Contents of P2O5 in squares and bolls and that of K2O in stems were higher in high-yield cotton than in CK during the whole growing period. The accumulations of N, P2O5 and K2O in the cotton plants could be described with a logistic curve equation. There was the fastest nutrient uptake at about 90 d for N, 92 d for P2O5 and 85 d for K2O after emergence, respectively. Total nutrient accumulation of N, P2O5 and K2O was 385.8, 244. 7 and 340.3 kg ha-1, respectively. Approximately 12. 5 kg N, 8. 0 kg P2O5 and 11.1 kg K2O were needed for producing 100 kg lint with the leaves and stems under the super high yield condition of 3 000 kg ha-1 in Xinjiang.

N、P、K肥对香根草修复土壤镉、锌污染效率的影响

通过盆栽试验研究在30 mg/kg镉(Cd)污染土壤条件下N[CO(NH2)2:100、200、300 mg/kg土]、P(P2O5:50、100、200 mg/kg土)和K(KCl:100、200、300 mg/kg土)处理对香根草修复土壤Cd和锌(Zn)污染效率的影响。结果表明:3种N处理能促进香根草地上部生长,而且显著提高地上部特别是叶的Cd和Zn含量,导致其修复效率成倍显著增加;200 mg/kg K处理显著提高Zn修复效率,但300 mg/kg K和50、200 mg/kg P处理却显著降低Cd、Zn修复效率。因此,为改善香根草对较贫瘠土壤中Cd、Zn污染的修复效率,应对香根草适施N肥,并控制或者不施P、K肥为佳。

河西走廊加工型胡萝卜N、P、K肥配施数学模型构建与优化方案研究

采用三因素二次回归通用旋转组合设计,研究氮肥、磷肥、钾肥对加工型胡萝卜产量的影响,结果表明:3因素影响加工型胡萝卜产量的顺序为:N肥>K肥>P肥,各因素间存在交互作用。经过计算机模拟,得到加工型胡萝卜产量达到最高值80.11t.hm-2时,其相对应N、P、K肥用量分别为1041.90kg.hm-2,177.15kg.hm-2和4059.45kg.hm-2。通过验证表明,模型选优所得N肥、P肥和K肥配比的产量最高,施肥成本、施肥利润、肥料投资效率分别为0.78万元.hm-2、1.50万元.hm-2和1.92,效果明显优于其他配比,证明构建的模型准确可靠。

盐渍土区棉花N、P、K肥效应研究

应用盆栽和田间试验对盐渍土棉花N、P、K肥效应进行了研究。结果表明 ,合理施用P、K肥能提高棉花体内过氧化物酶 (POD)活性 ,减少丙二醛 (MDA)含量 ,改善P、K营养 ,维持K+ 、Na+ 平衡 ,显著增强棉花耐盐性 ;合理增施N、P肥 ,可显著提高盐渍土棉花产量 ,有利于改善棉纤维品质 ,以N用量 1 95kg/hm2 、P2 O5用量 1 65kg/hm2(N1 95P1 6 5)

N、P、K三要素对水稻产量的效应分析

利用数学模型研究了N、P、K对水稻产量的影响 ,分析了单因素效应、双因素效应和边际效应 ,得出三要素对产量的贡献率大小依次为 :N 1.2 0 81、P 1.0 5 2 7、K 0 .8499;N和P互作明显 ;当P处于高水平时 ,N的增产效果明显。说明高N、P配合适当的K是提高水稻产量的重要途径之一。

The Systematics Study of (n, p) Reaction Cross-Sections at 14.7 MeV Neutron Energy

Based on the statistical model and taking into account the Q-value dependence and odd-even effects, we proposed a new empirical formula to reproduce the cross sections of the (n, p) reactions at 14.7 MeV neutron energy and at the target mass number 14 ≤ A ≤ 198 for even A and 29 ≤ A ≤ 205 for odd A. All calculated results from the proposed empirical formula were compared to the experimental data as well as the available semi-empirical formula obtained by other authors. A high level of agreement has been found between the collected experimental data and the most of semiempirical formulae obtained by others.

甬优12对N、P、K养分需求规律及施肥效应模型研究

为探明甬优12对N、P、K养分的需求规律和互作机制,明确肥料施用量与产量的关系,充分发挥甬优12的增产潜力,采用"3414"试验设计对其N、P、K养分需求效应进行了田间试验。结果表明,甬优12施用N、P、K后一般可增产20%以上,对N、P、K养分需求呈幂次函数变化规律,并且N+P+K(M)整体维度需求量明显大于N、P、K单维度需求量之和,其数学模型分别为Y=-0.7744N2+18.565N+510.01(r=0.9634*),Y=3.0931P2-8.6161P+604.66(r=0.9999**),Y=-3.3975K2+35.733K+521.45(r=0.9841*);Y=-0.1239M2+8.4834M+489.36(r=0.8010**)。通过对上述模型和通用N、P、K比例分析,甬优12对N+P+K组合互作最佳需求量为34 kg/667 m2,即纯N 14 kg、P2O57 kg、K2O 13 kg,其超高产栽培应在整体维度最佳需求量模型的基础上,加大有机肥配套和微量营养的合理促成,以健全群体与个体的关系,推动攻大穗、保多穗的超级栽培预期实现。

Double-gate tunnel field-effect transistor:Gate threshold voltage modeling and extraction

The tunnel field-effect transistor(TFET) is a potential candidate for the post-CMOS era.As one of the most important electrical parameters of a device,double gate TFET(DG-TFET) gate threshold voltage was studied.First,a numerical simulation study of transfer characteristic and gate threshold voltage in DG-TFET was reported.Then,a simple analytical model for DG-TFET gate threshold voltage VTG was built by solving quasi-two-dimensional Poisson equation in Si film.The model as a function of the drain voltage,the Si layer thickness,the gate length and the gate dielectric was discussed.It is shown that the proposed model is consistent with the simulation results.This model should be useful for further investigation of performance of circuits containing TFETs.

CuSO_4、MgSO_4、FeSO_4对绿豆N、P、K含量的影响

选用绿豆品种白绿9号,用浓度均为50mmol/L的CuSO_4、MgSO_4、FeSO_4溶液进行浸种、喷施、浸种+喷施处理,以蒸馏水处理为对照。探讨绿豆分枝期、开花期、成熟期Cu^(2+)、Mg^(2+)、Fe^(2+)各处理对绿豆根系、叶片、茎秆部位N、P、K含量的影响。结果表明:Cu^(2+)、Mg^(2+)在3个时期对N、P含量的降低作用较强,尤其降低P含量更强,且Cu^(2+)强于Mg^(2+);Cu^(2+)、Mg^(2+)对K含量有增加作用。Fe^(2+)从分枝期到成熟期对N、P、K含量一直起着增加作用。

Numerical simulation of the effect of the free carrier motilities on light-soaked a-Si:H p–i–n solar cell

Using a previous model, which was developed to describe the light-induced creation ofthe defect density in the a-Si：H gap states, we present in this work a computer simulation of the a-Si：H p-i-n solar cell behavior under continuous illumination. We have considered the simple case of a monochromatic light beam nonuniformly absorbed. As a consequence of this light-absorption profile, the increase of the dangling bond density is assumed to be inhomogeneous over the intrinsic layer （i-layer）. We investigate the internal variable profiles during illumination to understand in more detail the changes resulting from the light-induced degradation effect. Changes in the cell external parameters including the open circuit voltage, Voc, the short circuit current density, Jsc, the fill factor, FF, and the maximum power density, Pmax, are also presented. This shows, in addition, the free carrier mobility influence. The obtained results show that Voc seems to be the less affected parameter by the light-induced increase of the dangling bond density. Moreover, its degradation is very weak-sensitive to the free carrier mobility. Finally, the free hole mobility effect is found to be more important than that of electrons in the improvement of the solar cell performance.

高温热处理后的n—Ge的霍尔效应与电阻率

给出了具有相同电阻率的n－Ge样品经高温热处理后的霍尔系数和电阻率的实验结果，用热缺陷补偿及反型层[1]模型对常温反常霍尔效应进行了定性解释，进一步证实了反型居理论在常温区的正确性。

Interlayer coupling effect in van der Waals heterostructures of transition metal dichalcogenides

Van der Waals(vdW)heterobilayers formed by two-dimensional(2D)transition metal dichalcogenides(TMDCs)created a promising platform for various electronic and optical properties,ab initio band results indicate that the band offset of type-Ⅱband alignment in TMDCs vdW heterobilayer could be tuned by introducing Janus WSSe monolayer,instead of an external electric field.On the basis of symmetry analysis,the allowed interlayer hopping channels of TMDCs vdW heterobilayer were determined,and a four-level k·p model was developed to obtain the interlayer hopping.Results indicate that the interlayer coupling strength could be tuned by interlayer electric polarization featured by various band offsets.Moreover,the difference in the formation mechanism of interlayer valley excitons in different TMDCs vdW heterobilayers with various interlayer hopping strength was also clarified.

基于联合k/n(G)模型的DIMA系统可靠性建模与分析

针对分布式综合模块化航空电子(DIMA)系统的动态重构特性,分析了动态重构策略及重构过程,构建了面向DIMA系统的联合k/n(G)可靠性模型。以驻留于DIMA系统的综合显示功能为例进行了实验分析,讨论了系统重构过程可靠度与时间变化关系,给出了利用一般k/n(G)可靠性模型建模的可靠度变化曲线,通过对比分析验证了联合k/n(G)模型的适用性和合理性;通过参数敏感性分析,观察不同模块配置参数对系统可靠度的影响,得出相关结论,为提高DIMA系统动态重构过程的可靠性和优化资源配置提供指导。

鲁梅克斯K-1杂交酸模的施氮模型选择及氮肥推荐

对鲁梅克斯K 1杂交酸模的氮肥肥效试验表明 ,氮素营养是影响其产量的显著性因子 ,酸模的产量随施氮量增加近似线性地增加 ,达到最大值后在较大范围基本保持不变 ,氮肥推荐模型可采用线性加平台模型。植株的粗蛋白含量也在一定范围随施氮量增加显著增加 ,从对照的 2 1 98%提高到 2 8 2 3 %。植株的根冠重量比较大 ,在最佳施氮水平N3 ( 60 0kg·hm- 2 )下为 53 66%。根的粗蛋白的含量由对照的1 1 2 6%增加到N5( 90 0kg·hm- 2 )的 3 0 2 1 % ,表明酸模的根具有一定的储存和调控氮的能力 ,这可能是作物具有较强的耐氮性原因之一。

基于“克强指数”对中国GDP的混频预测研究

通过构建MIDAS混频数据模型,基于"克强指数"对中国季度GDP增长率进行预测研究,并与ADL同频模型的预测误差相比较,结果表明,MIDAS混频数据模型在预测精度上占优,因此可用月度"克强指数"对季度GDP增长率进行预测,为宏观经济政策的制定提供依据。

基于AGA-BP强预测的爬升段油耗估计

为准确预测燃油消耗量,减少民航碳排放,分析飞行数据影响油耗的参数,提出两种爬升阶段油耗预测模型,即BP预测模型与基于自适应(简写为A)GA-BP强预测模型。GA-BP强预测模型以BP预测网络为弱预测器,经有限次数迭代得到强预测器输出,实现误差的优化调整,解决非线性复杂问题。实验结果表明,该模型在非线性预测方面有明显优势,预测精度和拟合度较好,验证了两种模型在油耗预测领域都具可行性。

黄河三角洲盐渍土棉花施用氮、磷、钾肥的效应研究

为探讨盐渍土抗虫棉施用氮(N)、磷(P)、钾(K)肥的效应及其营养生理机制,指导滨海盐渍土抗虫棉合理施肥,在黄河三角洲盐渍土低、中、高盐棉田种植转Bt基因抗虫棉鲁棉研28,研究N、P、K肥配合施用对其养分吸收利用、Na+吸收积累、光合速率、干物质积累和产量的影响。结果表明,N、P肥配合,尤其是N、P、K肥配合施用显著增加了低、中、高盐田棉花的N、P、K养分吸收量,减少了Na+吸收积累量。低、中、高盐田棉花的N、P、K养分农学利用效率均以N、P、K配施的处理较高,氮养分农学利用效率分别为0.20、1.95和2.07kg皮棉kg-1N,磷养分农学利用效率分别为0.87、8.35和8.71kg皮棉kg-1P,钾养分农学利用效率分别为0.26、2.89和3.77kg皮棉kg-1K。N、P、K肥配合施用还维持了较高的棉株叶面积、叶绿素含量和净光合速率。低、中、高盐田棉花的生物产量和皮棉产量也均以N、P、K配施的处理较高,皮棉产量分别增产2.53%、28.67%和30.47%。中、高盐棉田的施肥效应明显好于低盐棉田。表明根据盐碱程度分类合理施肥是减轻盐渍土营养障碍、改善棉花营养、提高养分农学利用效率和棉花产量的有效途径。

氮、磷、钾不同施肥配比效应对人工混播草地产量与品质的影响

【目的】针对伊犁河流域水土资源开发,研究不同施肥配比对人工混播草地产量及品质的影响。【方法】运用"3414"施肥方案设计,研究不同N、P、K配比施肥对混播草地第2年产量及营养成分的影响。【结果】试验得出,施N 66.01 kg/hm2、P2O585.03 kg/hm2、K2O 23.75 kg/hm2时,三茬干草的最高产量达到14 617.86 kg/hm2;影响混播草地产量高低顺序为N肥>P肥>K肥,粗蛋白质含量与豆禾比有明显的规律性,当豆禾比大时,其粗蛋白质含量高。【结论】N、P、K合理配比施肥,对混播草地产草量具有明显的效应作用,对改善牧草品质、提高混播草地生产力具有积极效果。

贵州省低热地区早春番茄平衡施肥数学模型研究

[目的]为了研究贵州省低热地区N、P、K施用量与产量的相关关系。[方法]采用"3414"二次回归设计,以N、P、K为供试因子,番茄产量为目标函数,对贵州省低热地区早熟番茄施肥数学模型进行研究。[结果]根据建立的数学模型获得优化施肥技术方案:N、P、K最佳施用量分别为104.55、112.95、502.95 kg/hm2,产量可达115 719.00 kg/hm2。[结论]该研究为优化N、P、K肥施用量,制定番茄专家系统的施肥决策提供了依据。

肯氏南洋杉苗期施肥效应的研究

针对肯氏南洋杉苗期生长缓慢的问题,采用正交试验设计L9（3^4）,通过植物生长所需要的大量营养元素N、P、K 3因素3水平及其不同配比的施肥试验,分析了各元素及其水平对肯氏南洋杉苗高和地径生长的影响,确定了肯氏南洋杉苗期生长的最佳施肥方案。结果表明：18个月不同处理间都呈极显著差异,低水平的营养元素对促进肯氏南洋杉苗高和地径的生长好于高水平,以处理1即N1P1K1为施肥效果最好,且与其它处理呈极显著差异;对肯氏南洋杉苗高生长的影响为N〉P〉K,对肯氏南洋杉地径生长的影响为P〉K〉N。