Nacre-Inspired,Liquid Metal-Based Ultrasensitive Electronic Skin by Spatially Regulated Cracking Strategy

The realization of liquid metal-based wearable systems will be a milestone toward high-performance, integrated electronic skin. However, despite the revolutionary progress achieved in many other components of electronic skin, liquid metal-based flexible sensors still suffer from poor sensitivity due to the insufficient resistance change of liquid metal to deformation. Herein, a nacre-inspired architecture composed of a biphasic pattern (liquid metal with Cr/Cu underlayer) as “bricks” and strain-sensitive Ag film as “mortar” is developed, which breaks the long-standing sensitivity bottleneck of liquid metal-based electronic skin. With 2 orders of magnitude of sensitivity amplification while maintaining wide (>85%) working range, for the first time, liquid metal-based strain sensors rival the state-of-art counterparts. This liquid metal composite features spatially regulated cracking behavior. On the one hand, hard Cr cells locally modulate the strain distribution, which avoids premature cut-through cracks and prolongs the defect propagation in the adjacent Ag film. On the other hand, the separated liquid metal cells prevent unfavorable continuous liquid-metal paths and create crack-free regions during strain. Demonstrated in diverse scenarios, the proposed design concept may spark more applications of ultrasensitive liquid metal-based electronic skins, and reveals a pathway for sensor development via crack engineering.     

薄层罩面在高速公路预防性养护中的应用

结合广珠西高速路面超薄磨耗层的具体应用,论述了超薄磨耗层对原材料技术要求、配合比设计、施工工艺和施工关键技术控制等。     

埋地管道泄漏内封堵装置设计与研究

针对流体输送埋地管道泄漏问题,设计了一种利用管道机器人携带封堵气囊进行快速应急封堵修复的埋地管道泄漏内封堵装置。采用矩阵变换方法建立了牵引系统驱动轮过弯方程,利用MATLAB软件对过弯方程进行了验证,同时利用ADAMS软件仿真分析过弯路径与驱动轮转角对牵引系统行走速度的影响。研究结果表明:由两个串联封堵器组成的应急封堵系统可满足复杂工况下的管道泄漏封堵要求;牵引系统驱动轮在弯管内部行走时,单轮速度呈周期性变化,但三个驱动轮整体周期运动特性一致;驱动轮转角在25°~40°时,牵引系统行走速度与驱动轮转角成正比,且转角为30°时驱动效果最好。该内封堵装置的结构设计可为管道泄漏应急封堵领域装备的研发提供重要参考。     

SO4^2-／ZrO2固体超强酸的制备及其催化合成ETBE的研究

采用沉淀一浸渍法制备了负载型SO4^2-／ZrO2固体超强酸催化剂，运用IR、XRD等方法表征所制备催化剂的物化性质。结果表明，所制备的催化剂具有固体超强酸催化剂的特征，酸性与焙烧温度有关，适当提高焙烧温度有利于样品酸强度的提高，但焙烧温度过高会导致脱硫；浸渍液H2SO4浓度高有利于提高催化剂的硫含量，但是浓度过高，会在催化剂上形成硫酸盐，从而降低催化剂的比表面积和酸性。采用制备的催化剂气相催化乙醇与叔丁醇合成乙基叔丁基醚反应，乙基叔丁基醚的选择性为54．71％。     

小块气藏早期动态特征综合评价

应用试井方法，提出一套比较切合实际的小块气藏动态特征综合评价方法，推导出水驱气藏水侵量的计算公式，编制了天然气高压物性参数计算和气藏稳产年限预测等程序软件。     

超音速燃气射流非定常波系的数值研究

根据ＭＵＳＣＬ格式的基本思想，对格式进行了部分修改，数值模拟了超音速燃气射流流场的结构和发展过程。给出了流场谐波系的变化趋势，得到了流场达到稳定状态的时间和稳定后的流动图形。     

Microstructure-Property Correlation in AI_4C_3 Dispersion Strengthened Al Composite

The microstructure and tensile properties of Al_4C_3 dispersion strengthened Al composite fabricatedby reaction milling technique were investigated.It is indicated that the rod-like Al_4C_3 dispersoidshaving a diameter of 0.02-0.03 μm and a length of 0.1-0.3μm are formed by reaction of C with Al,and uniformly distributed in the Al matrix.The interface between Al_4C_3 and Al is clean and theinterfacial bonding is good.The matrix consists of the subgrains which have the size of 0.3-0.4μm,and most of the Al_4C_3 dispersoids are distributed on the subgrain boundaries.The 11 vol.-%Al_4C_3/Al composite exhibits an UTS (ultimate tensile strength) of 400 MPa and anelongation-to-failure of 8.0%.     

吉林省特大干旱灾害对粮食的影响及其对策

本文通过分析我省历史发生的特大干旱灾害事件，论述了不同时期特大干旱对粮食产量的严重影响。提出了21世纪特大干旱的研究与对策。     

椭圆型偏微分方程的加法Schwarz方法

1.引 言 古典加法Schwarz方法(ASM)对于一般问题收敛很慢,在大多数情况下, ASM只能作为预条件子.另一方面,ASM的并行性能非常好,尤其适合大规模粗粒度并行计算,近年来随着并行机系统及并行计算的兴起,ASM重新受到重视.许多学者研究了怎样提高ASM的收敛速度[1,2,4].他们发现加法Schwarz方法之所以收敛慢是由于在内边界上采用