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1.
通过广汉市秸秆捡拾打捆机的应用情况介绍、效益分析,提出了主要存在的问题及建议.  相似文献   

2.
利用盆栽试验研究了水分亏缺对抽穗期小麦穗轴维管束系统的影响。结果表明:穗轴大、小维管束数目、横截面积、导管直径和韧皮部面积沿穗轴由下到上依次减小。但下降幅度因维管束种类、穗轴部位而异。同正常供水处理相比,中度水分亏缺下穗轴大、小维管束数目、面积、导管直径和韧皮部面积有所减小。重度水分亏缺则使穗轴大、小维管束数目、面积、导管直径和韧皮部面积明显减小。表明水分亏缺显著改变了小麦穗轴维管束系统的显微解剖结构。  相似文献   

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在间接加热式热风炉的参数化设计中,蛇型管束的行数和列数随着设计参数的变化而变化,使得间接加热式热风炉三维参数化建模比较困难。采用面向对象的编程语言VB,以SolidWorks为平台,对蛇型管束进行了三维参数化设计建模,可按照输入的设计参数自动生成蛇型管束的三维实体模型,绘图速度快且精度高,大大提高了设计质量,为其他复杂零件的参数化设计提供了可供参考的经验。  相似文献   

5.
At present, the logarithm of time and the square root of time methods are usually used to compute consolidation coefficient, from which only a few data were adopted for the consolidation coefficient. At the same time, the two solutions depend on the initial value from the curves and influenced the exactitude of consolidation coefficient directly. So, in this paper, an improved least square method is supposed to compute the consolidation coefficient with testing data. According to the derived formulae, a program is used to compute consolidation coefficient based on Matlab language and to eliminate human error. The computation results show a good effect and give a reduction of errors.  相似文献   

6.
City squares are an important part of urban public spaces and play an important role in improving the quality of urban landscapes. For mountain cities, city squares with mountainous characteristics formed by its special geographical environment, which have more identifiability and uniqueness than that in plain cities, have greater influence on the promotion of city image. Their unique regional cultural characteristics and local customs and practices have shaped the totally different temperament of mountain cities. Based on the dialectical relationship between the square, the landscape and the culture, this paper took Shiyan Broadcasting Media Center Square for example to explore the ideas of landscape design in mountain cities.  相似文献   

7.
Under the background of stock planning,fine planning promotes intensive and efficient utilization to become an important measure of urban space utilization.The three-dimensional development of urban public space promotes the emergence and gradual growth of urban sunken square.However,there are many problems in the design of urban sunken square.In order to have a clear understanding of the current situation between the sunken square and the surrounding environment in the domestic mega city,the Shanghai Wujiaochang Sunken Square was selected for field investigation and questionnaire survey to understand the main problems and advantages and disadvantages in this case.The common problems were summarized and the disadvantages of the lack of integration between the sunken square and the surrounding environment were obtained and the role of integration of the two was clarified.It is expected that the design points of sunken square and surrounding environment integration can provide guidance for the follow-up design.  相似文献   

8.
This paper puts emphasis on the analysis about the space form and the vertical space utilization of the Renmin Square in Chongqing. It reveals that the design could get the best space effect if it was considered not only in two-dimension but in three-dimension as well.  相似文献   

9.
Wind tunnel tests were carried out to study the wind pressure on principal square building adjacent to another one in tandem. The interference effects on local pressure of the principal building were analyzed with different positions and heights of interfering building. It is shown that as height ratio is fixed, mean pressures on windward face are suctions when spacing ratio is less than 3, otherwise they are positive. The magnitudes of mean suctions on the side and leeward faces and fluctuating pressures on each face all get their maximums when spacing ratio is 3. As height ratios change, the magnitudes of mean suction on windward face increase with height ratio, meanwhile, the magnitudes on other faces obtain their minimums as the height ratio is 1.0 and the spacing ratio is less than 3. The fluctuating pressures on the windward and side faces get their maximums and that on the leeward face reaches its minimum as the height ratio is 1.0. When the spacing ratio is greater than 3, mean pressures on each face decrease, while fluctuating pressures on the windward and side faces increase as the height ratio increases, and the fluctuating pressures on the leeward face get the minimum when the height ratio is 1.0.  相似文献   

10.
水稻穗颈维管束数与穗部性状关系的研究   总被引:41,自引:3,他引:41  
籼粳亚种间F2群体穗颈大维管束数与穗颈小维管束数、1次枝梗数、1次枝梗粒数、2次枝梗数、2次枝梗粒娄和每穗粒数均呈显著或极显著的正相关;穗颈小维管束数与1次枝梗数、2次枝梗数、2次枝梗粒数和每粒数亦呈极显著的正相关;每穗粒数主要由2次枝梗粒数决定,而2次枝梗粒数主要由2次枝梗数决定,穗颈大、小维管束数和1次枝梗数通过2次枝数影响每穗粒数;穗颈维管束数主要受遗传因素控制,环境条件的影响相对较小,此外  相似文献   

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