Torsion behavior of Steel encased Concrete Composite Beams

In order to study torsion behavior of steel encased concrete composite beams, experiments were carried out with eight specimens. The destruction shape, working mechanism and the crack development and distribution were analyzed under pure torsion and combine torsion conditions. And also the relationships were investigated between torque and torsion ratio, load and strain, bending moment and deflection and load crack. On the basis of elasticity plastic theory, the formulas of cracking torsion were presented for pure torsion and combined torsion of combined beam. And with spatial truss model of variable angle, formulas for ultimate torsion strength of pure torsion and combined torsion were put forward. The predicted results were in good agreement with measured ones. The proposed formulas provided basis for evaluating safety and stability of the structural.     

Analysis of the distorted scaling factor in wind tunnel modeling of power transmission line system

Because of the limitation of the model making and the existing wind tunnel’s size, it is difficult to keep the line and tower in the same scaling factor in developing the aeroelastic model of the power transmission lines system, and a distorted scaling factor is needed in span length of the lines. With the instance of a 1 000 kV two circuit power transmission lines, the finite element analysis under the along wind load in time history is conducted with keeping the tower in the same and the line scaling factor being 1, 0.5 and 0.25 respectively. The results show that the response of the power transmission lines systems keep in the same, and then the wind induced vibration of the distorted model in the wind tunnel test can actually reflect the response of the power transmission lines system under the wind load.     

迷迭香的引种栽培研究

通过对引进的8个迷迭香品种在3个试验地的栽培试验研究。结果表明,迷迭香的高生长和冠幅生长在品种间存在显著差异,生长表现好的品种有SUBURY BLUE、UPRIGHT和标准迷迭香,高生长和冠幅生长在不同试验点间也存在显著差异,在乐昌市龙山林场种植的综合表现较好,文章还说明在粤北地区种植迷迭香合适的株行距离,以及修枝管理对迷迭香生长的影响。     

双轴向力学性能测试方法及其应用

阐述了双轴向测试的研究方法及其应用,为双轴向测试的系统研究提供参考,同时提出了双轴向测试在竹／木加工领域的应用现状及展望。     

基于虚拟仪器的农业测试技术教学与研究

虚拟仪器具有传统仪器不可比拟的优点而在农业生产中得到广泛的应用,它能执行测试、转换数据、分析等任务,也能够连接互联网和其他仪器以实现通信。以其完善的软件功能和简单的硬件结构完成强大功能。本文介绍了虚拟仪器概念、结构、特点,并且叙述了虚拟仪器技术在农业工程中的应用。     

测土配方施肥技术在甘蔗上的应用研究

为了探讨测土配方施肥技术在甘蔗上的应用效果,促进该项技术在甘蔗生产上迅速推广应用,2008年进行了测土配方施肥与常规施肥对比试验。结果表明,在相同的自然条件下,测土配方施肥能明显改善甘蔗的农艺经济性状,与常规施肥相比,增产糖料蔗4927．4kg／ha,增产率为5．65％,经济效益提高1359．35元／ha。     

应城市水稻肥料效应试验

为了更好地指导农民开展测土配方施肥,通过对一组水稻“3414”肥料效应试验结果的分析,对应城市水稻土壤的养分丰缺指标和水稻作物肥料养分施用指标进行了初步修订,     

SSR标记鉴定玉米品种真实性及纯度的研究

[目的]探讨杂交玉米及其亲本种子真实性和纯度的分子检测判读标准。[方法]以16个玉米杂交种及其双亲和202个骨干自交系为引物筛选材料,分别构建3个杂交种和3个自交系人工群体的验证试验材料,用CTAB法提取幼苗叶片DNA,选137对SSR引物进行SSR扩增及产物检测,用于玉米品种的真实性鉴定和纯度检测,并与同批移栽至大田的种植鉴定结果相比较。[结果]从137对SSR引物中筛选出了多态性信息含量（PIC值）高、扩增条带清晰和重复性好的20对一级和20对二级核心引物,用一级核心引物对杂交种人工群体进行真实性鉴定,根据一级核心引物的扩增结果,从中选取3对（phi080、umc1196、umc2084）表现较好的引物用于杂交种人工群体的纯度检测。ssR分子检测结果与田间种植鉴定结果具有高度一致性。[结论]利用SSR标记技术鉴定玉米品种真实性和纯度的方法是可行的。     

负二项式分布及种群格局检验分析

种群格局是种群生态学的重要研究内容之一。该文介绍了随机、均匀和集群3类种群空间格局的基本类型,以及与其相对应的概率分布函数,如正二项式分布、泊松分布和集群分布,重点讨论了在种群格局研究中被广泛应用的负二项式分布的内涵、分布函数的建立和参数的估计,对种群格局检验常用指标及其使用中存在的错误也进行了分析和讨论。      

关于测土配方施肥长效机制的探索与研究

本文系统全面的介绍了测土配方施肥的目的、意义,并针对现在项目实施情况所存在的一些问题,明确提出了今后工作的重点和主要做法。