Palladium‐Decorated Silicon Nanomesh Fabricated by Nanosphere Lithography for High Performance,Room Temperature Hydrogen Sensing

A hydrogen (H₂) gas sensor based on a silicon (Si) nanomesh structure decorated with palladium (Pd) nanoparticles is fabricated via polystyrene nanosphere lithography and top‐down fabrication processes. The gas sensor shows dramatically improved H₂ gas sensitivity compared with an Si thin film sensor without nanopatterns. Furthermore, a buffered oxide etchant treatment of the Si nanomesh structure results in an additional performance improvement. The final sensor device shows fast H₂ response and high selectivity to H₂ gas among other gases. The sensing performance is stable and shows repeatable responses in both dry and high humidity ambient environments. The sensor also shows high stability without noticeable performance degradation after one month. This approach allows the facile fabrication of high performance H₂ sensors via a cost‐effective, complementary metal–oxide–semiconductor (CMOS) compatible, and scalable nanopatterning method.     

Stretchable ITO-Free Organic Solar Cells with Intrinsic Anti-Reflection Substrate for High-Efficiency Outdoor and Indoor Energy Harvesting

Flexible photovoltaic devices are promising candidates for triggering the Internet of Things (IoT). However, the power conversion efficiencies (PCEs) of flexible organic photovoltaic (OPV) devices with high conductivity poly(3,4-ethylene dioxythiophene):polystyrene sulfonate (PEDOT:PSS) electrodes on plastic are lagging behind the rigid devices due to the low transmittance of polyethylene terephthalate (PET)/PEDOT:PSS. Moreover, the poor stretchability of the commonly used plastic substrates largely hinders the practical application of wearable devices. Herein, a novel stretchable indium tin oxide (ITO)-free OPV device with a surface-texturing polydimethylsiloxane (PDMS) substrate for outdoor strong- and indoor dim-light energy harvesting is reported. The high diffuse transmittance and haze effect of the substrate enable stretchable ITO-free devices, yielding a high PCE of 15.3% under 1 sun illumination. More excitingly, the stretchable device based on textured PDMS/PEDOT:PSS maintains a comparable PCE of 20.5% (20.8% for the rigid device) under indoor light illumination. Notably, the stretchable device is much more insensitive to the light direction, maintaining 38.5% of the initial PCE at an extremely small incident angle of 10° (16.3% for glass/ITO-based counterpart). The texturing stretchable substrate provides a new direction for achieving high performance and enhanced light utilization for the stretchable light-harvesting device, suitable for indoor and outdoor applications.     

空气变形装置气路系统设计

结合空气变形装置的要求，着重介绍气路系统管路的设计和主要供气设备的结构特点、选择步骤及计算方法。     

Vibration analysis and development of an ultrasonic elliptical vibration tool based on a portal frame structure

An ultrasonic elliptical vibration tool utilizing the coupled resonant vibration modes is the key component in the elliptical vibration cutting/texturing process, which has been successfully applied to ultra-precision machining and surface texturing. In this paper, an analytical approach is proposed to analyze the resonant frequency and mode shapes of the ultrasonic elliptical vibration tool. A new design of ultrasonic elliptical vibration tool based on a portal frame structure is presented and analyzed using the proposed model. The model assumes Euler-Bernoulli beams and utilizes the transfer matrix technique to reduce the order of the system to only six variables. The model can be utilized to provide a systematic approach for an optimal design and be extended to dynamic analysis of the tool for study of machine-tool dynamics. Finite element simulation results as well as experimental data based on the prototype design are presented to verify the model. An application of the proposed tool is also demonstrated in machining micro/nano-structured surfaces for structural coloration.     

激光毛化对镀铬层结晶位向及摩擦磨损性能的影响

针对激光毛化提高镀铬层硬度和耐磨性的现象,采用X-衍射测试不同状态铬层晶粒位向,利用晶粒密排面的排列位向定性分析铬层织构改变情况。结果表明,基体经毛化处理产生的高密度位错和表面形貌改善了电镀铬层织构,是使铬层硬度、耐磨性能提高的重要原因。     

化纤不同加工方式对着色涤纶长丝颜色的影响

分别对圆形截面和五叶形截面着色涤纶加弹丝和平行拉伸丝的颜色变化进行了测试研究。测试结果表明:加弹丝的颜色较拉伸丝明显偏浅并较为鲜艳;五叶形截面纤维的颜色明显浅于圆形截面纤维;随着纤维细度增加,纤维的基本色相没有变化,但纤维颜色变得更加“深”、“暗”。     

涤纶加弹机假捻皮圈的合理使用

对涤纶加弹机假捻皮圈假捻工艺参数的设定进行了探讨,研究了皮圈状况对DTY的物理指标、染 色状况和解捻张力的影响,提出通过调整皮圈表面线速度与丝条速度之比值,可弥补由于皮圈磨损对丝条染 色性能造成的不良影响。     

假捻变形的交络技术

德国Ｅｎｋａｔｅｃｎｉｃａ公司制造的ＴＤ喷嘴系列适用于假捻变形工艺的新进展,本文介绍了该喷嘴的结构,以及变形纱的质量测定方法。     

拉伸变形卷装机构原理分析与应用

为解决涤纶ＤＴＹ纺丝卷装成形中经常遇到的质量至ＦＫ６－９００型拉伸变形卷装机机构原理进行了分析,找出了常见故障及产生的原因,并提出了相应的处理方法。其结果对稳定拉伸变形工艺,提高产品质量起到良好的作用。