硅胶基衬底表面高分辨复杂可延展电路的印刷制备

 柔性可延展电子因其能够适应非平面工作环境,将突破现有电子器件的应用范围,促进信息与人的融合,在智能穿戴电子、柔性显示、生物医疗等领域具有广阔的应用前景。本文提出利用印刷结合真空抽滤方法实现硅胶基衬底表面高分辨复杂可延展电路的制备;研究了丝网印刷工艺实现微孔滤膜表面银纳米线（Ag NWs）图形化沉积的分辨率;讨论了Ag NWs线长、抽滤真空度等因素对沉积分辨率的影响,实现了Ag NWs图形化50 μm线径分辨率及间隔分辨率。本文还研究了硅胶基衬底表面微电极的电阻均一性及拉伸电阻稳定性,并结合电极表面微结构的变化详细讨论了屈曲褶皱结构的出现对微电极拉伸电阻的影响,实现了100 μm线宽微电极100%拉伸幅度下电阻增加仅为初始值的40%。最后,通过集成LED芯片演示了面料基底表面柔性可延展发光电路。本研究对于柔性可延展电路的制备提供了新的思路。     

干湿交替对砂岩断裂特性影响试验研究

周期性的水岩相互作用对岩石的物理力学性能有较大的影响,被认为是影响岩土工程安全稳定性的重要因素之一。以典型的均质青砂岩为试验对象,利用中心裂纹圆盘试件开展了砂岩I~II复合型断裂试验,研究了干湿交替作用对砂岩I~II复合型断裂特性的影响;通过观测干湿交替后砂岩微观结构的变化特征,探讨了干湿交替作用的劣化机理;并结合复合型断裂则对试验结果进行了有效评估。研究表明,砂岩的纯I型,纯II型以及I~II复合型断裂韧度均随着干湿交替次数的增加而逐渐减小;其劣化趋势基本一致,但劣化程度略有不同。当加载角较大或II型分量主导时,干湿交替作用对砂岩断裂韧度的劣化影响更为显著。考虑了T应力影响的广义最大周向应变准则和广义最大周向应力准则都能对试验结果进行很好的预测。在纯II型时,基于广义最大周向应变准则的理论预测值比基于广义最大周向应力准则的理论值更接近试验值。     

Highly stretchable,sensitive and wide linear responsive fabric-based strain sensors with a self-segregated carbon nanotube (CNT)/Polydimethylsiloxane (PDMS) coating

Flexible strain sensors have received increasing attention with the development of wearable electronic devices. However, integrating wide strain detection range, high sensitivity while maintaining relatively wide linear response range for such sensor system still remain a challenge. A fabric based flexible sensor (S-CNT/PDMS-F) was designed and fabricated, and the sensor can simultaneously achieve high sensitivity, wide linear response and strain detection range by combining self-segregated carbon nanotube (CNT)/polydimethylsiloxane (PDMS) composites and elastic medical bandage. It has been observed that this new sensor system can achieve a high sensitivity with a gauge factor of 615, a large linear responsive range of 0–100% strain (R² ?= ?0.993) and a wide strain detection range of ～ 200%, which is superior to almost all the reported CNT/PDMS flexible strain sensors. Compared to the similar fabric based strain sensor system deploying non self-segregated structure (C-CNT/PDMS-F), our S-CNT/PDMS-F demonstrates higher electrical conductivity and lower electrical percolation threshold and response time of 55 ?ms, as well as more stable and repeatable performance under cyclic loading conditions. The capability of the sensors in monitoring physiological activities and weight distribution has also been demonstrated.     

羟基磷灰石/碳纳米管复合生物材料的制备与表征

为了赋予碳纳米管(CNTs)表面良好的生物性能,拓展CNTs在硬组织生物材料及组织工程支架材料中的应用,采用化学共沉淀和水热后处理法宏量制备了羟基磷灰石(HA)/多壁碳纳米管(MWCNTs)复合材料,通过调节制备过程中浓硝酸纯化的MWCNTs加入量,考察不同MWCNTs含量的HA/MWCNTs复合材料的结合形式.扫描电子显微镜(SEM)和透射电镜(TEM)表征结果表明,当ω(MWCNTs)＝15%时,MWCNTs表面均匀地包覆了一层由纳米HA晶粒紧密相连的膜层,在此情况下MWCNTs与纳米HA形成最佳结合状态.体外细胞培养实验表明,制备的HA/MWCNTs复合材料具有良好的生物相容性.     

改善酶固定以增强葡萄糖传感器的生物电化学活性

研制了一种基于多壁碳纳米管(MWCNTs)和氧化锌(ZnO)纳米颗粒协同作用的高灵敏稳定的葡萄糖传感器. 将ZnO颗粒淀积在带有负电荷的MWCNTs层上,由于等电点（IEP）的差异,葡萄糖氧化酶（GOx）能够牢固地固定在ZnO颗粒表面,最后将一层带正电的的聚二烯丙基二甲基氯化铵(PDDA)覆盖在GOx上. 这种特殊的自组装三明治结构(PDDA/GOx/ZnO/MWCNTs)能够很好地保持GOx的活性并防止酶泄露. 在0.05 mol/L的磷酸盐缓冲溶液（pH=6.8）中进行检测,电压为100 mV(参比为Ag/AgCl电极);用0.5单位GOx测得线性反应区域为0.1~16 mmol/L;用2.0单位GOx测得灵敏度为50.2 (mA&;#8226;cm^-2&;#8226;mol^-1),检测下限为 250 nmol/L (3σ) . 通过葡萄糖传感器直接检测100例人血清,与临床光学检测的结果比较发现,相关系数达到0.997.     

Fabrication and Characterization of Polypyrrole/Polyurethane/Polyamide/Polyamide Yarn-Based Strain Sensor

Yarn-based strain sensors serve as essential elements for wearable electronics in the applications of personal health monitoring, motion detection, and smart garments. In the paper, a yarn-based strain sensor was created by coating conductive polymer, polypyrrole(PPy), onto a double covered elastic yarn, i.e., polyurethane/polyamide/polyamide(PU/PA/PA) yarn. Surface morphology of the yarn-based strain sensors demonstrates that the PPy conductive particles are evenly distributed on the surface of the PA multi-filaments as well as immersed into the PU core. Cyclic tensile test is conducted to characterize the electro-mechanical performance of the yarn-based strain sensor. The mechanical hysteresis of the sensor is low, which mainly comes from the geometrical change of the PA filaments around the PU core. However, the electro-mechanical hysteresis of the sensor is large mainly due to the unrecoverable cracks of the PPy layers on the PU core.     

Preparation and Characterization of Resistive Strain Sensor Based on Braided Skin-Core Rope

This study proposed a new yarn-like strain sensor on the basis of the braided skin-core rope,and investigated the effect of braiding structures on the sensing properties of sensors. The morphology and electromechanical properties of the strain sensor with different braiding structures were compared and evaluated. The results show that the sensing performance of the sensor from a braided skin-core rope depends on both the number of yarns in braiding and the metallized process of braided rope. Generally,the present stretchable skin-core rope-based sensor provides a basis for the formation of a highly sensitive sensing structure.     

超薄六维力/力矩传感器优化设计及其解耦

为降低六维力/力矩传感器的高度尺寸对基座和驱动部件引起的附加力矩,结合有限元分析法、SDO方法和神经网络方法,设计了一种新型的基于应变检测原理的超薄六维力/力矩传感器,其高度尺寸可控制在15mm以内.为进一步提高设计的六维力/力矩传感器的精度,对其进行非线性维间解耦和标定,实验结果表明,传感器精度性能优良,最大线性度误差为0.15%F.S.,其设计和优化过程正确合理,最大耦合误差为1.6%F.S.,各维在满量程时的输出相等,具有各维同性.     

气固两相流静电传感器特性的研究

基于点电荷的概念,设计了气固两相流传感器的静电感应实验装置,并实验研究了传感器环状电极的几何尺寸对传感器性能的影响．结果表明,对于直径相同的电极,其长度越短,所构成的传感器的通带频宽越大,但传感器的能量传递系数却变小．因此在设计传感器时,应综合考虑频宽与能量传递系数对测量结果的影响．     

碳纳米管柔性应变传感器在智能纺织品中的应用

智能纺织品不仅拥有日常穿着的所需功能,而且兼具智能性,柔性纺织材料的选择是当前纺织材料研究的重点。在柔性材料中,碳材料是制备柔性应变传感器的理想材料之一。以碳纳米管为柔性材料制备的柔性应变传感器在智能纺织品中的应用为研究内容,从碳纳米管的结构组成、性质及其应用等方面,介绍碳纳米管柔性应变传感器的研究现状;从材料选择、制备方法、性能测试及应用等方面,阐述以碳纳米管纤维和碳纳米管薄膜为柔性材料制备的柔性应变传感器的特性和功能;从制备难点、生产成本、实际应用效果等方面,对碳纳米管柔性应变传感器的优缺点进行评述。研究认为,在大应变下具有高灵敏度将是今后碳纳米管柔性应变传感器研究的方向。     

电流型氢渗透传感器研究

利用Devanathan-Stachurski电解池原理制造恒电解式与电池式电流型氢渗透传感器,用于监测氢在钢中的扩散速率及浓度.研究了镀镍时间、密封电解液对渗氢电流的影响,试验了以羟基氧化镍粉末作为阴极材料的电池型氢渗透传感器.实验结果表明:钢件表面镀镍5 min作为原子氢催化氧化的集氢面,经约5 h氧化后可以消除电镀渗氢的影响,使背景电流降至0.5 μA/cm~2以下;由聚乙烯醇和羧甲基纤维素钠按质量比4∶1混合,再与0.2 mol/L KOH溶液配制成非流动性的电解液作为密封胶,用于传感器内部电解液与工件镀镍面之间的密封,与单电解液的测量结果一致;在相同充氢条件下,恒电解式与电池式电流型氢渗透传感器测得的氢渗透曲线结果一致,与施加氧化电势的方式无关.     

基于薄壁应变筒的光纤布拉格光栅压力传感器

综述光纤布拉格光栅的传感机理，研制基于薄壁应变筒的光纤布拉格光栅压力传感器。该传感器力灵敏度高，同时又能实现温度补偿；其结构简单，易干工业化生产。对静态特性实验研究结果表明，该传感器系统具有比常规的压力传感器更优越的性能，     

Evaluation of cable tension sensors of FAST reflector from the perspective of EMI

The active reflector of FAST(five-hundred-meter aperture spherical radio telescope) is supported by a ring beam and a cable-net structure,in which nodes are actively controlled to form series of real-time paraboloids.To ensure the security and stability of the supporting structure,tension must be monitored for some typical cables.Considering the stringent requirements in accuracy and longterm stability,magnetic flux sensor,vibrating wire strain gauge and fiber bragg grating strain gauge are screened for the cable tension monitoring of the supporting cable-net.Specifically,receivers of radio telescopes have strict restriction on electro magnetic interference(EMI) or radio frequency interference(RFI).These three types of sensors are evaluated from the view of EMI/RFI.Firstly,these fundamentals are theoretically analyzed.Secondly,typical sensor signals are collected in the time and analyzed in the frequency domain,which shows the characteristic in the frequency domain.Finally,typical sensors are tested in an anechoic chamber to get the EMI levels.Theoretical analysis shows that Fiber Bragg Grating strain gauge itself will not lead to EMI/RFI.According to GJB151 A,frequency domain analysis and test results show that for the vibrating wire strain gauge and magnetic flux sensor themselves,testable EMI/RFI levels are typically below the background noise of the anechoic chamber.FAST finally choses these three sensors as the monitoring sensors of its cable tension.The proposed study is also a reference to the monitoring equipment selection of other radio telescopes and large structures.     

光纤布拉格光栅湿度传感器研究

基于光纤布拉格光栅(FBG)的应力传感特性,提出了一种湿度传感方法,给出了湿度传感器的设计和实验测量系统。理论推导显示,涂有湿敏材料的FBG对湿度的传感可转化为对应变的快速响应,结合温度的有效补偿,可以共同反映在FBG中心反射波长的漂移上。研究结果表明,FBG湿度传感器能在较大温度范围内保持线性特性,并具有稳定性持久、响应速度快等优点。     

单根In掺杂的n-ZnO纳米线/p+-Si异质结的紫外电致发光

采用化学气相沉积的方法在In_0.1Ga_0.9N衬底上生长出In掺杂的n-ZnO纳米线阵列。电学输运测量得到单根n-ZnO纳米线的电阻率为0.001 Ω cm,比同样方法在GaN衬底上生长的ZnO纳米线低约20倍。这个结果表明来自于In_0.1Ga_0.9N衬底中的In原子在高温生长过程中可能被掺入ZnO纳米线。制备成功单根n-ZnO纳米线/p⁺-Si异质结构并研究了其电致发光特性。室温下电致发光光谱中可以看到一个窄的ZnO激子峰（约380 nm）和一个中心位于700 nm 的来自Si衬底表面自然氧化硅发光中心的发光峰。     

悬梁式磁流体惯性传感建模及输出可控性分析

提出在传统悬臂梁传感器结构中引入纳米功能材料磁流体,基于磁流体的磁粘可控特性,实现悬臂梁传感器的输出可控性.重点为建立其传感数学模型并进行运动分析,求得动态函数表达式,借助仿真数值方法得到传感模型中的幅值比与阻尼比、频率比的关系曲线,并对传感器可控性进行分析.结果表明,通过改变磁流体的粘度可实现传感器的输出可控性,最终实现宽量程传感测量,研究得出采用二脂基磁流体,选取激励电流为1.2A时磁流体传感量程可放大超过10倍.     

电子探空仪气压传感器特性

为了掌握电子探空仪气压传感器的测量性能及不同气压传感器的特性差异对测量准确度的影响,对硅压阻和电容膜盒2种气压传感器进行了一定时间的存储测试试验.利用同一环境下某一测试时间的气压标准值与传感器测量值的差值分析了2种气压传感器的一致性,根据该差值随时间的变化分析了2种气压传感器的稳定性.结果表明,2种气压传感器的稳定性都...     

Si NWs/GQDs复合结构的设计及其光电催化性能

采用金属催化化学蚀刻法制备硅纳米线阵列（silicon nanowire arrays,Si NWs）,通过高速旋涂仪将自上而下法制备的石墨烯量子点（graphene quantum dots, GQDs）负载到Si NWs上。X射线光电子能谱（X-ray photoelectron spectroscopy, XPS）等表征结果证明,GQDs能够通过高速旋涂仪负载到Si NWs上。扫描电子显微镜（scanning electron microscopy, SEM）形貌观测结果表明,蚀刻时间与Si NWs纳米线长度成正比。光电化学测试结果表明,性能最优的蚀刻时间为45 min。与原始硅片相比,GQDs负载的Si NWs光电密度达到了0.95 mA/cm²,性能提升了30多倍。电化学交流阻抗（electrochemical impedance spectroscopy, EIS）测试结果表明：GQDs的加入能显著提升载流子的传输效率。紫外–可见漫反射光谱（ultravioletray-visible diffuse reflectance spectroscopy, UV-Vis DRS）结果显示负载GQDs可以有效提升Si NWs对光的吸收效果。     

智能CFRP加固RC梁荷载效应模拟与测评

将布拉格光栅光纤（FBG）传感器固化于碳纤维复合材料（CFRP）试件中,构成智能CFRP,试验结果表明：FBG传感器与CFRP相容性良好;FBG传感器与传统电阻应变片具有理想线性关系,FBG的应变传感特性精确稳定．制备4根CFRP加固RC实验梁,并在受拉钢筋、压区混凝土及底部加固CFRP中预置了FBG传感器．根据FBG传感原理、钢筋混凝土理论和Ansys有限元软件编制RC梁荷载效应模拟程序．对实验梁进行弯曲加载实验．根据置入CFRP中FBG传感器的监测应变值,应用有限元模拟计算程序得到梁实时模拟荷载及诸项荷载效应模拟值．结果表明：受拉钢筋与压区混凝土实时模拟应变与传感器实测应变相符合,模拟挠度与实测挠度也相符合,模拟实时荷载与实际荷载基本一致．从而达到集加固与测评双重功能于一体的目的。     

光纤光栅应变传感器在仿真混凝土拱坝模型试验中应用

采用了一种基于两端夹持不锈铜管封装技术的光纤光栅应变传感器,利用万能试验机对该传感器进行了应变性能标定试验,研究了不同基体材料上传感器的应变灵敏特性.测试结果与理论结果吻合较好.将埋入武光纤光栅应变传感器应用到仿真混凝土拱坝的抗震安全性分析试验中.试验结果表明,基于两端夹持封装技术的光纤光栅传感器具有良好的灵敏度、低噪...