甜玉米LCYE等位基因多态性及功能分析

【目的】鉴定甜玉米材料中LCYE基因的多态性和β-胡萝卜素和类胡萝卜素含量的变异,为了解甜玉米LCYE基因的等位基因功能及维生素A源强化育种提供参考和依据.【方法】以47份甜玉米自交系为材料,用高效液相色谱法检测β-胡萝卜素和总类胡萝卜素的含量,扩增LCYE基因并测序,结合LCYE基因的测序结果和β-胡萝卜素、总类胡萝卜素含量的表型值作关联分析.【结果和结论】在47份甜玉米自交系的LCYE基因的测序结果中共发现75个多态性位点,其中49个多态性位点分布在非编码区,26个多态性位点分布于LCYE基因的外显子区,且均为SNP,第5外显子区多态性位点最丰富,第4和第9外显子区未检测到多态性位点,其保守程度较高.关联分析检测到与β-胡萝卜素相关联的位点3个,与总类胡萝卜素含量关联的位点6个,位点exon1-2和exon5-6与2种表型极显著相关.本研究证明在甜玉米中LCYE基因与β-胡萝卜素和类胡萝卜素的合成显著相关,为甜玉米的维生素A源强化育种提供了理论基础.     

闽江流域生态公益林林型对水源涵养的影响

【目的】分析林型与降雨量、径流量的关系,为合理调整闽江流域内生态公益林林型结构布局,充分发挥公益林的水源涵养功能提供参考。【方法】以闽江流域为研究对象,借助遥感(Remote sensing,RS)和地理信息系统(Geographic information system,GIS)技术手段,对闽江流域HJ-1A/B CCD遥感影像进行处理,在提取生态公益林资源信息的基础上,结合水文数据,采用灰色关联分析法,研究流域内不同林型与年降雨量、年径流量之间的关系。【结果】经过遥感影像处理和森林资源信息提取,获得了闽江流域30个县市的多年平均径流深和降雨量栅格图及生态公益林森林资源分布图。灰色关联分析结果表明,流域内6种林型阔叶林、杉木林、马尾松林、针阔混交林、竹林、经济林与年径流量的关联度分别为0.599 6,0.544 1,0.529 8,0.546 9,0.501 5,0.457 3;与年降雨量的关联度分别为0.574 3,0.757 1,0.783 0,0.729 1,0.853 8,0.882 1。各县市生态公益林的涵养水源能力以大田、闽清、三明、沙县、尤溪等较强,德化、仙游、古田和福州、建瓯、明溪等表现为从一般到较强,光泽和武夷山最差。【结论】流域内不同林型的水源涵养能力大小依次为阔叶林针阔混交林杉木林马尾松林竹林经济林;当阔叶林、杉木林、针阔混交林面积分别约占有林地面积的20%,18%和26%时,森林涵养水源的能力较强。     

不同氮素利用效率基因型油菜氮素营养性状的差异

【目的】研究盆栽条件下不同氮素利用效率基因型油菜氮素营养性状的差异,为揭示植物高效利用氮素的机理和氮高效基因型油菜品种的选育提供依据。【方法】在低氮(施N 0.1g/kg)和高氮(施N 0.3g/kg)条件下,采用土培盆栽试验对50份不同基因型甘蓝型油菜的氮利用效率进行分析,从中筛选氮高效基因型和氮低效基因型油菜,研究不同氮利用效率基因型油菜各器官及其不同生长阶段的氮含量、氮素累积量及各器官氮累积量占植株总氮素累积量的比例的差异。【结果】1)油菜氮利用效率与籽粒、果荚皮壳、茎叶氮含量均呈显著或极显著负相关,无论氮素供应水平高低,氮高效基因型各器官氮含量均低于氮低效基因型。2)高氮条件下,油菜氮利用效率与果荚皮壳、茎叶、根系氮素累积量和植株总氮累积量均呈显著或极显著负相关;成熟期氮高效基因型油菜果荚皮壳、茎叶、根系氮素累积量和总氮素累积量均显著低于氮低效基因型。低氮条件下,油菜氮利用效率与成熟期果荚皮壳、茎叶氮素累积量均呈显著或极显著负相关,而与成熟期籽粒氮素累积量和植株总氮累积量呈显著正相关;氮高效基因型油菜的籽粒氮素累积量显著高于氮低效基因型,果荚皮壳和茎叶氮素累积量均低于氮低效基因型,总氮素累积量高于氮低效基因型。3)高氮条件下,油菜氮利用效率与茎叶和根系氮素累积量占总氮素累积量的比例均呈显著或极显著负相关,而与籽粒氮素累积量占植株总氮素累积量的比例呈极显著正相关;氮高效基因型油菜籽粒氮素累积量占总氮素累积量的比例明显高于氮低效基因型,而茎叶和根系氮素累积量占植株总氮素累积量的比例均明显低于氮低效基因型。在低氮条件下,油菜氮利用效率与果荚皮壳、茎叶和根系氮素累积量占植株总氮素累积量的比例均呈显著或极显著负相关,而与籽粒氮素累积量占植株总氮素累积量的比例呈正相关;氮高效基因型籽粒氮素累积量占总氮素累积量的比例明显高于氮低效基因型,而果荚皮壳和茎叶氮素累积量占总氮素累积量的比例则明显低于氮低效基因型。4)相对于氮低效基因型,氮高效基因型油菜氮含量对氮素反应更敏感;氮低效基因型油菜氮素累积量对氮素供应水平的敏感性较氮高效基因型油菜高。无论是氮高效基因型还是氮低效基因型,茎叶和果荚皮壳氮含量及氮素累积量对氮素的反应均较籽粒和根系敏感。【结论】不同氮素利用效率油菜的氮含量、氮素累积量和氮素分配比例以及对供氮水平的敏感性存在明显差异。     

Ultimate Bearing Capacity Analysis of High Strength Single Angle Compression Member Eccentrically at One End

To analyze mechanical behavior of Q460 high strength single angle steel struts with an eccentric load at one end in transmission towers, experimental analysis and theoretical calculation were carried out to study the overall stability and local buckling of members. Spherical hinge bearing and double knife edge bearing were applied at axial end of specimens. Influence of some factors on bearing capacity of compression members with eccentricities at both ends was analyzed, such as the end supporting conditions and residual stresses. It was shown that whether spherical hinge bearing or double knife edge bearing was used at axial end, the mechanical behavior can be accurately presented and the residual stresses affected the ultimate load carrying capacity by about 5％ or less. Compared with different methods, such as experiment method、finite element method, method in the Guide for American Design of Latticed Steel Transmission Structure（ASCE101997）and method in Chinese Technical Regulation of Design for Tower and Pole Structure of Overhead Transmission Line (DL/T51542002), it was found that the calculated strength of high strength steel member by standard calculation method in DL/T51542000 was over conservative. According to the research results, the revised formulas of ASCE were proposed with dividing actual material strength by the resistance coefficient of rR=1.111. Therefore, the experimental results can provide reference for designing high strength Q460 single angle steel members compressed eccentrically at one end.     

Dynamic analysis and optimization of gear trains in a megawatt level wind turbine

Through coupling vibration analysis of the transmission system of a 1.5 MW wind turbine gearbox, a torsional vibration model of a gear drive system in wind turbines is established. The fourth order Runge Kutta integration method is applied to calculate the dynamic response of a gear system caused by wind loads, time varying meshing stiffness, and system damping. The harmonic balance method is used to find the analytic solution. Based on the solution, a mathematical model for optimum gear system design is established. The model aims at minimizing the vibration acceleration of the planet gear and the total mass of the gear transmission system. The optimization toolbox in MATLAB program is adopted to obtain the optimal solution. A calculated example shows that the primary natural frequency of the gear system has been raised, the dynamic properties of the gear train have been improved remarkably, and the total mass of the gear train has been decreased.     

Numerical analysis on the performance of spiral antennas

The surfaces of the Planar Spiral Antennas and Conical Spiral Antennas are analyzed with planar triangle. The surface currents of the antennas are solved by using the Method of Moment (MoM) based on the RWG basis function. The input impedance, directivity, gain, radiated power and radiation field of the antenna can be found. The results indicate that, in very wide frequency band, the value of the input impedance equals to the theoretical value of Self-Compensated antennas (in agreement with Babinet-booker' principle), which is,188.5 ohm , the half of the wave impedance of free space, while the directivity, gain and radiated power are stable within the frequency band. When the antenna is driven by the signal of derivative Gaussian pulse, the radiating electric field waveform is obtained by the Fourier transform. When the spiral antenna is used as the pulse radiation antenna, the waveform of the radiation electric field shows the characteristics of the Gaussian quadratic differential.     

Numerical analysis of noise radiation from motorcycle engine shell

FEM/BEM (Finite Element Method/Boundary Element Method) mode analysis of the noise radiation from motorcycle engine shell is conducted. The natural frequency is compared between FEM/BEM analysis and experimental analysis. The FEM/BEM results are agreed with the experiment results, which proves that the finite element model is correct. The frequency response is analyzed and the structure’s noise radiation is simulated by means of FEM/BEM, in order to predict the noise radiation from the motorcycle engine shell and gain the sound field characteristic outside the structure. The calculation data is compared with the experiment data in different frequency bands. The result shows high accordance, which indicates that this method is effective.     

高产、优质、抗病、强分蘖外源春小麦新品种—陇春32号

陇春32号是甘肃省农业科学院生物技术研究所将强抗逆作物米高梁基因组DNA通过花粉管通道法导人感病受体小麦89122-16后,结合D1代幼胚培养挽救加代稳定技术,经早代表型变异筛选、常规优良性状选拔、分子标记及HMW-GS检测、抗锈性鉴定、品质分析等手段,历经10年选育而成的高产、优质、抗病、强分蘖及综合性状优良的春小麦新品种.该品种于2014年通过甘肃省农作物品种审定委员会审定,品种审定号为甘审麦2014002.     

日粮能量水平对1.5～3.5月龄獭兔免疫性能及肝脏IFN-γ表达的影响

【目的】研究日粮不同能量水平对獭兔免疫性能及IFN-γ表达量的影响,为獭兔饲养能量标准的制定提供科学依据。【方法】将160只1.5月龄獭兔随机分为Ⅰ、Ⅱ、Ⅲ、Ⅳ4组,每组40只,分别饲喂消化能为9.7,10.5,11.3和12.1MJ/kg的4种日粮(各日粮其他营养成分一致);预试期7d,正试期2个月;每个月采样1次,进行相关免疫指标的测定。【结果】在日粮能量水平为9.7~11.3 MJ/kg时,獭兔的免疫器官指数、免疫球蛋白含量以及肝脏IFN-γ表达量均随日粮能量水平的升高呈现出一定的规律性。2.5月龄时,Ⅰ组与Ⅳ组肝脏指数、脾脏指数、IgG含量以及肝脏IFN-γ表达量的差异均达到了显著水平(P0.05)。3.5月龄时,Ⅰ组与Ⅲ组的脾脏指数、IgG和SIgA含量及Ⅰ组与Ⅳ组的肝脏IFN-γ表达量均差异显著(P0.05)。【结论】在日粮能量水平为9.7~11.3MJ/kg时,日粮能量水平的升高能够增大獭兔的免疫器官指数,促进獭兔免疫球蛋白的分泌以及肝脏IFN-γ的表达,獭兔日粮较适宜的消化能水平为11.3MJ/kg。     

陇东黄土丘陵区梯田土壤养分评价——以甘肃庄浪县为例

【目的】从县域尺度对陇东黄土丘陵区梯田土壤养分进行评价,为黄土丘陵区梯田土壤培肥、粮食产量增加提供科学依据。【方法】以庄浪县耕地质量评价数据为数据源,共采集3 839个样点,且采样点均匀覆盖全县农田,通过主成分分析和方差成分估计模块分析了陇东黄土区梯田土壤大量养分（有机质、全磷、全氮、缓效钾、速效磷、碱解氮、速效钾）和微量养分（有效铜、有效锌、有效锰、有效铁、有效硼）分布特征及其影响因素。【结果】1）庄浪县梯田土壤全磷和速效磷含量处于高水平,速效钾含量处于较高水平,有机质、全氮和碱解氮含量处于中等水平。土壤大量养分综合指数处于较低、中等和较高级别的样本数分别占有效样本数的14.45%,65.89%和19.66%。2）庄浪县梯田土壤有效铜、有效锰和有效铁含量为中等水平,有效锌和有效硼含量处于中下水平,且有较大面积的土壤缺硼。土壤微量养分综合指数处于较低、中等和较高级别的样本数分别占有效样本数的32.53%,63.35%和4.12%。3）土壤类型对土壤大量养分空间变异的贡献率达51.81%,海拔影响次之,其贡献率为23.60%。随着海拔的升高,土壤大量养分综合指数在较高水平样本所占比例相应增加。4）土壤微量养分空间变异性与土壤类型、土壤质地、海拔有关,土壤类型对微量养分空间变异的贡献率最高,为69.41%,土壤质地、海拔的贡献率分别为17.65%,11.76%。随着海拔的升高,土壤微量养分综合指数在中高水平所占比例总体降低。【结论】陇东黄土丘陵区梯田土壤大量养分和微量养分整体处于中等水平,有较大面积的土壤缺硼。梯田土壤养分的空间变异主要受土壤类型和海拔的影响。