克里金插值平滑效应校正及凤冈县富硒茶园适宜区研究

【目的】研究克里金插值数据平滑效应的校正方法及其在富硒茶园适宜区研究中的应用。【方法】用采样点插值表面估计值和实测值极差和标准差的相对变化率定量表示克里金插值的平滑效应,用样点插值表面估计值和实测值的最小值、平均值和最大值之间的一元二次回归方程为校正函数,用贵州省凤冈县0-20 cm土层的pH和全硒含量校正克里金插值表面叠加分析研究富硒茶园适宜区。【结果】（1)极差平滑率和标准差平滑率可分别描述克里金插值数据变化范围平滑效应和数据变异程度平滑效应,凤冈县土壤pH和硒含量普通克里金插值的极差平滑率和标准差平滑率分别为68.30%、69.51%和65.33%、60.00%。（2）校正后凤冈县土壤pH插值表面估计值极差平滑率和标准差平滑率分别为0.00%和6.10%,硒含量插值表面估计值极差平滑率和标准差平滑率均为0。文中的校正方法可完美消除普通克里金插值平滑效应,同时保证插值结果无偏估计特性。（3）校正后插值表面叠加分析结果表明,凤冈县富硒茶园适宜区面积为49.63 km2,占全县土地总面积的2.64%,主要分布在该县永安镇田坝村及附近。【结论】用样点插值表面估计值和实测值的最小值、平均值和最大值之间的一元二次回归方程对克里金插值表面进行校正简单易行,基于校正表面富硒茶园适宜区分析结果与现实情况吻合良好。     

河南省渔业增加值的加权Markov残差修正预测研究

引入友精度指标,基于加权马尔可夫链(Markov)理论提出了灰色残差修正模型,并运用马尔可夫状态转移矩阵对未来残差的符号进行判定.以1994-2011年河南省渔业增加值为基础,建立预测模型,并在模型中不断加入新信息,进行实证分析.结果表明,与传统的灰色预测相比,预测值平均相对误差由8.33％降低为2.54％,较好地提高了预测的精度.     

基于近红外光声光谱的土壤有机质含量定量建模方法

该研究的目的在于应用近红外光声光谱技术结合不同的定量分析方法实现5种不同类型土壤有机质含量的快速估测。对中国中、东部地区5种不同类型土壤风干样本进行光谱扫描,经过多元散射校正、一阶导数、二阶导数及平滑等预处理后,应用逐步多元回归(SMLR)、主成分分析(PCR)、偏最小二乘法(PLS)和偏最小二乘法-反向传播神经网络(PLS-BPNN)等方法建立土壤有机质含量的定量估测模型。结果显示,不同预处理方法对所建土壤有机质含量估测模型的预测精度有较大影响,总体表现为多元散射校正+Norris一阶导数>多元散射校正>Norris一阶导数>标准正态化>Norris二阶导数>吸光度>Savitzky-Golay平滑后一阶导数>Savitzky-Golay平滑后二阶导数。对于4种不同建模方法,均以多元散射校正+Norris一阶导数滤波平滑后的光谱建模精度最高,其中采用PLS-BPNN方法建模效果最好,其次是PLS、SMLR和PCR。采用PLS-BPNN建立有机质校正模型具有极高的预测精度,建模决定系数和均方根偏差分别为0.97和1.88,模型测试决定系数和均方根偏差分别为0.97和1.72。因此,基于多元散射校正+Norris一阶导数光谱建立的PLS-BPNN模型可能是土壤有机质含量估测建模的最优方法。     

Tuber yield and allocation of nutrients and carbohydrates in potato plants as affected by limestone type and magnesium supply

Abstract

Magnesium (Mg) is a nutrient that affects the development of plants and is mainly supplied through liming performed to correct soil acidity. By acting on photosynthesis and influencing carbohydrate partitioning in the plant, supplementary Mg supplied through soil or foliar application can increase the yield and quality of potato (Solanum tuberosum L.) tubers. The aim of this study was to evaluate the effect of supplemental Mg fertilization by soil or foliar application on plant nutritional status, tuber yield, and carbohydrate partitioning in potato crops in soil corrected with calcitic and dolomitic limestones. The experiment was carried out in pots under greenhouse conditions with a randomized block design in a 2?×?3 factorial scheme with four replications. Dolomitic limestone application and supplemental Mg fertilization via soil increased the concentrations of this nutrient in potato leaves. Liming with dolomitic limestone reduced the uptake of Ca and K by plants, but supplemental Mg fertilization did not alter the uptake of Ca, Mg or K. Supplemental Mg fertilization did not increase plant growth and tuber yield, even when calcitic limestone was used to elevate the base saturation to 60%; the exchangeable Mg concentration in soil was 9?mmol_c dm^?3, and the Ca:Mg relationship was 3.7. Liming with dolomitic limestone or providing supplemental Mg fertilization did not increase sugar and starch partitioning to the tubers.     

QC4115T柴油机启动困难的试验分析与解决方案

在试验分析的基础上查找了4PY340W喷油泵配QC4115T柴油机冷启动困难的原因。通过增加启动弹簧刚度和减小负校正量,有效地改善了柴油机的启动性能,使问题得以圆满解决。     

Linear and Cyclophosphates as Sources of Phosphorus for Corn

Abstract

Cyclophosphates are not adsorbed by soil constituents and can be mobile in the soil profile. Mobile phosphorus (P) sources are of interest in soil science and for agronomic practices. Cyclotri (Na₃P₃O₉; C3P), and cyclotetraphosphate (Na₄P₄O₁₀; C4P) were compared to linear, ortho‐, pyro‐, and tripolyphosphate in four soils with different chemical, physical, and biological properties to determine their mobility and availability to corn (Zea mays, L.) in laboratory and greenhouse experiments. Cyclophosphate (C3P and C4P) hydrolysis products were evaluated by ion chromatography after incubating for 6 to 192 h with 100 and 200 µg P g^?1 soil. Phosphorus distribution and mobility, and plant availability and uptake with time, were determined in 45‐cm columns for four soils. Cyclophosphates sorbed less and moved deeper in all soils compared to the linear phosphates. The results showed that after 24 h a large proportion of cyclophosphates (34% of C3P and 37% of C4P) remained unhydrolyzed in Falba sandy acid soil. Split application of C3P and C4P at planting and at booting stage increased corn yield in sandy acid soil. Results of this experiment suggest that P deficiency after plant establishment can be corrected with cyclophosphates in soils with a low potential for cyclo‐P hydrolysis.     

苹果RAPD标记的引物筛选与RAPD校正

为筛选适宜苹果的RAPD引物，以苹果富士与舞姿的杂交后代为试材，依据RAPD校正方法、利用引物OPAl3构建了苹果的RAPD校正图谱；在520个RAPD引物中找出了扩增稳定、条带清晰的246个引物，其中扩增条带数在8个以上的有91个引物，可用于苹果的遗传分析。探讨了RAPD-PCR反应条件与RAPD校正的关系，RAPD校正能够提高RAPD-PCR的扩增能力。     

基于协整和误差校正理论的中国建造价格水平预测研究

基于向量自回归理论,构建了能充分刻画中国建造价格、在建大中型建设项目数、建筑企业数、城镇失业率、广义货币供给量及已完大中型建设项目数6个向量间动态关系的VAR(2)模型,通过对此VAR(2)模型的协整分析和误差校正模型分析,充分考虑VAR(2)模型内变量间的长期均衡和短期波动,构建了中国建造价格预测模型,克服了用时间序列技术和多元回归技术在预测中国建造价格时的缺陷。     

应用约翰逊法估测美新杂交褐牛体重

[目的]新疆地区通过引进美国瑞士褐牛导入杂交改良新疆褐牛,以提高新疆褐牛品质和生产性能。研究旨在校正约翰逊估测法中系数,准确估测美新杂交褐牛体重,为今后新疆褐牛选育提高和新类型培育中体重测定提供方法。[方法]试验共测定美新杂交褐牛生产母牛283头,包括体重、体斜长和胸围,通过实测体重与约翰逊法估测体重比较分析,校正约翰逊法公式中系数,再进行验证。[结果]结果表明,美新杂交褐牛实测体重极显著低于约翰逊法估测体重(P0.01),对约翰逊法公式中的系数校正,校正后系数为12 300,即经过校正后的美新杂交褐牛体重约翰逊法估测公式为:体重=胸围~2×体斜长/12300,该公式在50头美新杂交褐牛进行验证,实测体重与估测体重差异不显著(P0.05),说明校正系数后的约翰逊法公式用来估测美新杂交褐牛估测体重可行,但本次试验实测和验证牛群数较少,还需大量不断验证以获得更可靠的结果。     

内蒙古经济增长与产业结构变动关系研究

协整检验表明内蒙古经济增长和产业结构变动之间存在长期的动态均衡关系,经济总量与第二、三产业产值结构同向变动,而与第一产业产值结构呈反向变动;同时,由相关性分析可知,第三产业在促进经济增长方面起主导作用,第一产业与第二产业具有显著相关性.