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本文介绍厌氧膨胀颗粒污泥床通过增大反应器的高径比和采用出水回流技术,使反应器内的水力上升流速远远高于UASB反应器,强化了传质效果,提高了处理效率的结构特性及其优势,以及厌氧颗粒污泥膨胀床的启动、在生活污水和工业废水处理中的研究应用概况,同时对研究与应用的前景提出了看法. 相似文献
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Sundial solar tracking machines are machines that tracking the sun,and can promote sunshine receiving efficiency of solar panels.Their operations are strongly influenced by wind load.Previous studies w... 相似文献
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针对目前网络地质研究局限于2维的现状,基于Flex、ArcGIS Server等关键技术设计并实现了REST式的兴城全景野外地质信息系统。应用结果表明:系统能够为地质研究人员提供露头-手标本尺度的地质构造、岩石组成和结构构造方面的信息,提高了研究效率;基于Flex的富客户端的应用程序执行速度快、功能丰富、交互性强。 相似文献
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The growth of gold nanoparticles in zeolite can be controlled using ion-exchange reactions and thermal reduction processes. We produce a number of different sizes of the gold nanoparticles with the particle size increasing with increased temperature of the final heat treatment. 相似文献
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A novel wearable sensor system was developed for monitoring respiration and pulse using polyvinylidene fluoride (PVDF) piezoelectric films as sensor materials. Due to the different signal intensity between respiration and pulse, a “double-sided arch” structure and a “thin-shell” structure were designed and fabricated as substrates for the respiratory sensor and pulse sensor, respectively. These sensors installed on belts can be easily tied on the chest, abdomen, or wrist for comfortable fit. In order to obtain clear respiratory and pulse signals from the sensor patch, some high-quality signal processing modules were designed. The digital signals were transmitted to a computer via Bluetooth and displayed by LabVIEW software. The fundamental principle and functional verification of the developed sensor system were described in this study. By comparing the sensor signals from the proposed structure with those of flat structure, it can be concluded that the proposed sensor is more sensitive and stable than its flat counterpart. In addition, the whole sensor system has the features of ease of use and comfortable to wear. All these make the proposed sensor system a promising sensing device for respiration and pulse real time monitoring. 相似文献
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《Measurement》2016
Laser forming continues to be a promising technology in manufacturing due to its fast speed, flexibility, and low-cost. Measurement of deformation after laser forming is widely needed to verify its convergence to the intended shape in academic research. With the development of laser forming, high requirements on the measurement of the deformed work-piece have been sought such as a 3D profile of the deformed surface, a large measuring range, and measuring convenience. In this paper, a laser-based machine vision measurement system was developed to measure the 3D profile of deformed surface by a one-off scanning process. Based on the 3D profile data, the vertical displacement of the deformed plate was calculated for bending analysis. In addition, as one of the important feature parameters, transverse shrinkage was automatically determined through a novel image-based method during the scanning process. A measuring accuracy of 0.03 mm for vertical displacement measurement and 0.0125 mm for transverse shrinkage were achieved in the developed measurement system. This measurement performance is acceptable in most of the laser forming processes currently studied. 相似文献
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由于微纳卫星反作用飞轮的输出力矩与气浮转台的干扰力矩属于同一量级,故无法直接采用气浮转台实现微纳卫星姿态动力学仿真及姿控系统的地面试验验证。为了解决这一问题,设计并研制了主动补偿式超低干扰力矩气浮转台。对气浮转台的干扰力矩进行分析,提出了3种减小干扰力矩的方法:通过优化设计,降低了黏滞阻尼力矩;通过配置斜向节流孔,并单独供气,产生大小可调的主动涡流以抵消气浮轴承的固有涡流,从而降低涡流力矩;利用气浮轴承的摆动特性实现高精度平衡调节,减弱了重力诱导力矩。最后,设计了微小力矩测量装置,测量了剩余干扰力矩并基于测试结果来指导涡流力矩和重力诱导力矩补偿过程。测试结果显示:气浮转台实现的干扰力矩小于5×10-5 Nm,小于反作用飞轮的最小输出1×10-4 Nm,满足微纳卫星姿态动力学及控制的地面验证需求。 相似文献
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为了实现基于可调谐激光吸收光谱技术的高检测灵敏度、低功耗、小型中红外痕量气体传感器设计,结合锑化镓(GaSb)ICL和紧凑型多反射气体吸收气室(MPC)研制了基于不同结构传感光学核的两个小型TDLAS传感系统。两个传感光学核的总功率消耗为3.7 W,并通过探测甲烷(CH4)和甲醛(CH2O)分别验证了双层结构和单层结构系统的性能。实验结果表明:CH4和CH2O系统的检测灵敏度分别为5.0nL/L和3.0nL/L,测量精度分别为1.4nL/L和1.0nL/L。此外,相同配置情况下将两种结构系统应用于甲、乙烷(C2H6)同步检测,通过对校园环境中甲、乙烷进行连续66h的监测试验,验证了设计的紧凑型中红外痕量气体检测系统能够稳定有效地工作,基本满足目前民用气体测量的稳定可靠、精度高、抗干扰能力强等要求。 相似文献