大中型方捆捡拾打捆机整机原理研究

以大中型方捆捡拾打捆机为研究对象,介绍了其基本结构组成,对整机设计原理进行了研究。分析了打捆机各部件相位耦合关系;进行了打捆机捡拾轨道盘轨迹研究;针对不同的作业原料,选择合适的喂料形式;研究了大截面均匀布料和整机自动控制系统设计原理,为大中型打捆机整机设计奠定基础。     

UG软件在《工程制图》教学中的应用

探讨了UG软件在《工程制图》课程教学中的应用,并举例说明UG软件的重要性和应用优势,全面实现2D与3D之间的自如转换,从而让学生更加清晰、直观地学会《工程制图》课程,提高教学质量,为培养卓越工程师夯实基础。同时,说明UG软件在《工程制图》课程中具有相当重要的作用。      

SolidWorks管路设计在污水处理设备中的应用

将SolidWorks管道设计功能应用于污水处理设备的设计中,探讨了自定义零件的创建方法以及管道零件库的建立方法,并基于上述方法,介绍了如何按自底向上的顺序完成污水处理设备三维管路的设计工作。      

基于ADAMS的果树采摘机械臂的运动仿真分析

根据对苹果园区的实地考察,利用Inventor软件建立了GY-1型果树采摘机器人机械臂的实体模型,完成装配。利用Inventor、Pro/E、ADAMS 2005这3种软件之间的接口技术,把机械臂模型导入ADAMS/View模块中。经过有效简化结构,对各个关节和液压缸分别添加约束和驱动,最终生成机械臂的虚拟样机。在ADAMS仿真中,通过计算各个液压缸的运动驱动函数,模拟了机械臂的一组采摘动作,得出机械臂上几个关键关节的受力变化曲线。通过对曲线结果的分析可以获得机械臂采摘时各关节的实时运动信息,为后续工作研究奠定了理论基础。     

水果表面缺陷自动检测系统中的人工智能方法研究

通过计算机视觉技术获取了带有各种表面缺陷的苹果图像并进行预处理，采用自适应特征聚类（ＳＡＦＣ）神经网络与模糊加权决策树（ＦＷＤＴ）相结合的方法实现了缺陷区域的准确检测和详细分类。实验结果表明，用人工智能方法进行表面缺陷检测，具有良好的抗噪容错能力并能有效地克服传统图像分割方法适应性差的缺点，提高判别准确率和分类精度。     

水稻白叶枯病黄单胞菌中与甘蓝黑腐病黄单胞菌致病因子调控基因(rpf 基因)同源基因的分子克隆

DNA-DNA 杂交结果表明,水稻白叶枯病黄单胞菌总 DNA 中存在着与甘蓝黑腐病黄单胞菌致病因子调控基因(rpf 基因)具有同源性的 DNA 外段.应用广谱性寄主载体pLAFRI,在大肠杆菌中建立了水稻白叶枯病黄单胞菌野生型菌株 T3000的基因文库.从文库中筛选到与 rpf 基因具有同源性的克隆 pGXN3000,将重组质粒 pGXN3000通过三亲本接合转入甘蓝黑腐病黄单胞菌 rpf 基因突变体,发现 pGXN3000能互补甘蓝黑腐病黄单胞菌 rpf突变体,恢复其致病性胞外酶和胞外多糖的产生及致病性.转座子 Tn5诱变,缺失分析及DNA-DNA 杂交实验结果表明,重组质粒 pGXN3000中确实含有与甘蓝黑腐病黄单胞菌编码。双组份调控系统”蛋白的 rpfC 基因功能相同的基因,此基因被定位于 pGXN3000中的3kb BamHl 片段中。     

黄土丘陵区不同下垫面降雨产流与蓄水窖工艺技术

在山西洪洞建立了农膜、公路、农田小路、农田下垫面产流场，对不同下垫面的降雨产流量及蓄水窖主要工艺技术体系进行了研究。结果表明：在观测的27次降雨中，在同一坡度、同一降雨量条件下，不同下垫面的产流量存在较大差异。农膜、公路、农田小路和农田下垫面的产流量分别占总降雨量的81.4％、73.6％、41.6％、2.7%。表明前三者均有较好的集水效果，而农田产流效果较差。研究提出的蓄水窖主要工艺技术体系经大面积示范收到了较好的效果。     

Antimicrobial peptides released by enzymatic hydrolysis of hen egg white lysozyme

This work was aimed at the isolation, purification, and characterization of novel antimicrobial peptides from chicken egg white lysozyme hydrolysate, obtained by peptic digestion and subsequent tryptic digestion. The hydrolysate was composed of over 20 small peptides of less than 1000 Da, and had no enzymatic activity. The water-soluble peptide mixture showed bacteriostatic activity against Gram-positive bacteria (Staphylococcus aureus 23-394) and Gram-negative bacteria (Escherichia coli K-12). Two bacteriostatic peptides were purified and sequenced. One peptide, with the sequence Ile-Val-Ser-Asp-Gly-Asp-Gly-Met-Asn-Ala-Trp, inhibited Gram-negative bacteria E. coli K-12 and corresponded to amino acid residues 98-108, which are located in the middle part of the helix-loop-helix. Another novel antimicrobial peptide inhibited S. aureus 23-394 and was determined to have the sequence His-Gly-Leu-Asp-Asn-Tyr-Arg, corresponding to amino acid residues 15-21 of lysozyme. These peptides broadened the antimicrobial activity of lysozyme to include Gram-negative bacteria. The results obtained in this study indicate that lysozyme possesses nonenzymatic bacteriostatic domains in its primary sequence and they are released by proteolytic hydrolysis.     

Evaluation of a combined penetrometer for simultaneous measurement of penetration resistance and soil water content

A combined penetrometer is an appropriate tool to measure the soil cone resistance and the water‐content profile. As a relatively new technique, a combined capacitance‐penetrometer for the simultaneous measurement of cone index and soil water content was developed at the Department of Agricultural Engineering of Bonn University in 2002. The objective of this study was the evaluation of the effectiveness and applicability of the innovated penetrometer with a focus on three aspects: (1) A capacitance sensor with two electrode configurations was calibrated for silt loam, sandy loam, and sand. The calibration results show that both electrode configurations have sufficient water‐content sensitivity, but soil‐specific calibrations seem necessary. (2) Under laboratory conditions, the dynamic resolution and response of the capacitance‐penetrometer were validated, and its radius of influence was determined. (3) The field measurement results demonstrate that this measurement technique can be used to improve the interpretation quality of soil cone index data.     

基于GIS的地下水资源可持续性评价

该文根据区域水资源评价工作的特点和GIS技术强大的空间分析功能,探讨了GIS技术在区域水资源可持续性评价中的可行性,并将其应用到北京市通州区潞城镇地下水资源可持续性评价中。根据GIS技术与动态均衡法的结合,评价得出自1988年以来,潞城镇地下水储量一直处于亏损状态,16年累计亏损1715.577万m³,地下水位平均每年下降0.12 m。表明今后该区域地下水应采取相应措施来缓解地下水的压力。