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离双向液压锁是混凝土泵车支腿液压系统的关键零部件,其功能是在系统停止供油时,将支腿垂直液压油缸的有杆腔和无杆腔锁住,使支腿垂直液压油缸能在其行程范围内任意位置长时间停留.本文通过对返厂故障双向液压锁测试,根据测试结果,分析了故障原因,提出了改进措施,为双向液压锁结构设计及优化提供参考. 相似文献
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立体视觉图像校正是加速立体匹配简单而常用的技术之一。采用几何法对使用棱镜的单镜头立体视觉系统图像进行校正,根据成像原理,从图像平面像素点反推到三维实体点的分析运算,利用成像光线几何关系求解虚拟相机外部参数,实现极线的校正,避免了复杂相机标定过程。同时,该算法可以从双棱镜应用推广到多面棱镜的单棱镜立体视觉系统图像校正。实验结果表明,基于几何法对使用棱镜的单镜头立体视觉系统图像校正是有效的。 相似文献
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城市污水处理厂污泥产生量大,含有丰富的有机质、氮、磷、钾等农作物所需营养物质,但由于受重金属的污染使污泥无法直接农用。本文简述了城市污泥重金属的来源、特点及危害。重点论述了城市污泥中重金属去除和稳定方法,包括化学法(电化学法、化学试剂法)、生物法(微生物法、植物法、低等动物法)、物理法(超临界流体萃取、微波和超声)及联合技术。分析了各种方法处理污泥重金属过程中重金属的形态变化及其对处理效果的影响,对比各种方法的优缺点、影响因素及适用范围。指出污泥中重金属形态分布是影响去除效果的关键因素,污泥中重金属形态分布差异性大,且大部分重金属以稳定或相对稳定的状态存在,导致物理法和生物法去除效率较低,微生物和低等动物处理法相比植物法(备受时空限制)则表现出更好的适应性;电化学法对可氧化、可还原态分布的重金属都能起到较好的转化去除作用,但往往受由污泥向污泥液相中转移过程的控制,电损耗较突出;化学试剂浸提剂是目前效率较高的方法,但强酸环境常导致污泥营养物质流失和酸根离子累积,农用时容易板结而不利于污泥土地利用。因此,以土地利用为前提的条件下,将各种处理技术联合运用以提高污泥重金属去除率有待于进一步研究。 相似文献
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Guangfeng Wang Jian Meng Hongying Liu Shoufeng Jiao Wei Zhang Daolei Chen Bin Fang 《Electrochimica acta》2008,53(6):2837-2843
A glassy carbon electrode modified with LaHCF was constructed and was characterized by cyclic voltammetry (CV) and electrochemical impedance spectrum (EIS). The resulting LaHCF modified glassy carbon electrode had a good catalytic character on uric acid (UA) and was used to detect uric acid and ascorbic acid (AA) simultaneously. This modified electrode exhibits potent and persistent electron-mediating behavior followed by well-separated oxidation peaks towards UA and AA with activation overpotential. For UA and AA in mixture, one can well separate from the other with a potential large enough to allow the determination of one in presence of the other. The DPV peak currents obtained increased linearly on the UA in the range of 2.0 × 10−7 to 1.0 × 10−4 mol/L with the detection limit (signal-to-noise ratio was 3) for UA 1.0 × 10−7 mol/L. The proposed method showed excellent selectivity and stability, and the determination of UA and AA simultaneously in urine was satisfactory. 相似文献
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This paper proposes a new method for rectification of single-lens stereovision system with a triprism. The image plane of this camera will capture three different views of the same scene behind the filter in one shot. These three sub-images can be taken as the images captured by three virtual cameras which are generated by the three Face (3F) filter (triprism). A geometry-based method is proposed to determine the pose of virtual cameras and obtain the rotational and translational transformation matrix to real camera. At the same time, the parallelogram rule and refraction rule are employed to determine the desired sketch ray functions. Followed by this, the rectification transformation matrix which applied on the images captured using the system is computed. The approach based on geometry analysis of ray sketching is significantly a simpler implementation: it does not require the usual complicated calibration process. Experimental results are presented to show the effectiveness of the approach. 相似文献
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半导体纳米晶具有量子尺寸效应和独特的光学性质,可广泛地应用在光电器件、生物标记、太阳能电池、光催化等方面,因此半导体纳米晶成为越来越多研究者研究的热点。但在诸多的应用限制因素中,高性能的QDs材料(Ⅱ-Ⅵ或Ⅳ-Ⅵ)通常含有镉或铅等剧毒的元素,批量生产和使用这类材料不仅对人体有着极大的伤害,还会引起环境和生态问题。因此低毒性能的QDs材料的设计和研发是目前研究的前沿之一。研究人员通过控制反应条件、表面包裹以及掺杂等对磷化铟(InP)材料的性能进行调控,使之能够更好地应用于各个领域之中。 相似文献