Self‐Recovering Triboelectric Nanogenerator as Active Multifunctional Sensors

A novel self‐recovering triboelectric nanogenerator (STENG) driven by airflow is designed as active multifunctional sensors. A spring is assembled into the STENG and enables the nanogenerator to have self‐recovering characteristic. The maximum output voltage and current of the STENG is about 251 V and 56 μA, respectively, corresponding to an output power of 3.1 mW. The STENG can act as an active multifunctional sensors that includes a humidity sensor, airflow rate sensor, and motion sensor. The STENG‐based humidity sensor has a wide detection range of 20%–100%, rapid response time of 18 ms, and recovery time of 80 ms. Besides, the STENG could be utilized in the application of security monitoring. This work expands practical applications of triboelectric nanogenerators as active sensors with advantages of simple fabrication and low cost.     

基于高能量转换效率的旋转式气动发动机动力学分析

针对目前常用气动发动机能量转换效率低的现状,提出一种新型旋转凸轮活塞式气动发动机结构。根据气动发动机工作原理,针对旋转式气动发动机膨胀容积大,缸内高压气体压力直接推动凸轮活塞旋转对外做功的结构特点,分析缸内气体压力与输出扭矩之间的关系,建立动力学模型,并以此动力学模型为基础,利用Matlab/Simulink软件对该发动机单缸工作过程进行计算机仿真分析。仿真结果表明:旋转式气动发动机具有低速时有效扭矩大,能量转换效率高的优点。     

混凝-粉末活性炭吸附-超滤工艺去除砂滤池反洗水溶解性有机物

通过混凝-粉末活性炭(PAC)吸附-浸没式超滤膜(UF)组合工艺去除砂滤池反洗水(FBWW)中溶解性有机物(DOM),以降低后续回用过程中消毒副产物(DBPs)生成量。试验对3种混凝药剂——聚合硫酸铁(PFS)、三氯化铁(FeCl3)、聚合氯化铝(PACl)处理FBWW的效果进行了比较,探讨其对UV254和水溶性有机物(DOC)的去除效果。结果表明,PFS对有机物去除效果优于PACl和FeCl3;PFS与粉末活性炭混合投加可增加有机物去除率,粉末活性炭为20mg/L,PFS为8mg/L时出水浊度为0.85NTU,UV254和DOC去除率分别为43%和31%;采用混凝-PAC吸附-超滤膜(UF)处理FBWW对UV254和DOC去除率分别达到51%和41%,出水浊度为0.19NTU,UV254为0.031cm-1,DOC为2.76mg/L.此工艺可有效降低反冲洗水中DOM含量,达到重新利用净水厂废水的目标.     

重庆彩电中心变电站原址带电整体改造

介绍在重庆彩电中心变电站有限的空间范围内,原址带电整体改造,包括项目改造背景、方案选择、工艺负荷供电模式、改造内容和工程施工方法等。     

液压支架电液控制系统设计

根据液压支架电液控制系统在国内外的应用现状,介绍了综采工作面液压支架电液控制系统的组成和功能,并自主设计了液压支架控制器、采煤机位置检测系统、巷道主机和本质安全型网络。实际的推广应用表明液压支架电液控制系统可实现液压支架就地控制、远程监控及其配套设备跟机自动控制。     

高端液压支架关键技术研究与产业化进展

介绍高端液压支架技术发展背景,提出基于液压支架与围岩耦合的三维动态优化设计方法,通过对高强度焊接结构钢、支架结构件残余应力分析、焊接机器人、电液控制系统和大缸径抗冲击立柱等关键制造技术的综合研究与应用,推进了高端液压支架产业化发展;最后总结了系列高端液压支架研制和产业化实施效果,如成功研制的ZY1700/32/70D、ZF150000/28/56等高端液压支架,寿命达到50 000次工作循环。     

砚北煤矿厚煤层综放面液压支架选型与应用

通过对砚北煤矿2502采区开采过程中矿山压力显现情况的分析和计算,确定了1504采区综放工作面液压支架的工作阻力,并结合工作面掘进过程中的矿压显现情况,选择了能够满足现场实际需求的支架类别和结构形式。现工作面已推采1 200余m,在几次矿压显现中,震动能量达3.66×106 J,工作面支架和两巷道的超前支架均能满足可靠支护要求。     

新型机械加长杆立柱的设计

为了更加科学地发挥液压支架中加长杆立柱的使用性能,通过对传统液压支架加长杆立柱的结构及受力优缺点进行分析研究,结合实际及其他领域设计经验,设计出一种新型的液压支架用机械加长杆立柱(已申请专利)。通过对2种结构的加长杆立柱进行结构及受力比较试验,试验结果表明该新型结构的机械加长杆立柱要优于传统结构加长杆立柱,有很好的应用前景。     

Membrane‐Based Self‐Powered Triboelectric Sensors for Pressure Change Detection and Its Uses in Security Surveillance and Healthcare Monitoring

A new membrane‐based triboelectric sensor (M‐TES) is presented as a self‐powered pressure change sensor. It generates a voltage induced by surface triboelectric charges in response to an air pressure change. Extremely high detection resolutions of 0.34 Pa and 0.16 Pa are achieved when the air pressure increases and decreases in a small region away from the ambient standard atmosphere pressure, respectively, indicating an excellent sensitivity. By integrating the M‐TES with a signal processing unit, we demonstrate practical applications of the device in sensing footsteps, respirations, and heartbeat, which suggests widespread use of the M‐TES in fields of security surveillance, chemical engineering, geography research, environment monitoring, and personal healthcare.     

Triboelectric Nanogenerator as an Active UV Photodetector

Self‐powered nanosensors and nanosystems have attracted significant attention in the past decades and have gradually become the most desirable and promising prototype for environmental protection/detection because no battery is needed to power the device. Therefore, in this paper a design is proposed for a self‐powered photodetector based on triboelectric nanogenerator (TENG) configuration. 3D dendritic TiO₂ nanostructures are synthesized as the built‐in UV photodetector as well as the contact material of the TENG. The cost‐effective, robust, and easily fabricated TENG‐based photodetector presents superior photoresponse characteristics, which include an excellent responsivity over 280 A W^?1, rapid rise time (18 ms) and decay time (31 ms), and a wide detection range of light intensity from 20 μW cm^?2 to 7 mW cm^?2. In the last part of the paper, a stand‐alone and self‐powered environmental sensing device is developed by applying poly(methyl methacrylate) (PMMA) substrates and springs to assemble the TENG‐based photodetector. These results indicate that the new prototype sensing device based on the TENG configuration shows great potential as a self‐powered photodetector.