Skin electronics from scalable fabrication of an intrinsically stretchable transistor array

Wang, Sihong,Xu, Jie,Wang, Weichen,Wang, Ging-Ji Nathan,Rastak, Reza,Molina-Lopez, Francisco,Chung, Jong Won,Niu, Simiao,Feig, Vivian R.,Lopez, Jeffery,Lei, Ting,Kwon, Soon-Ki,Kim, Yeongin,Foudeh, Ami Macmillan Publishers Limited, part of Springer Nat 2018 Nature Vol.555 No.7694

Skin-like electronics that can adhere seamlessly to human skin or within the body are highly desirable for applications such as health monitoring, medical treatment, medical implants and biological studies, and for technologies that include human–machine interfaces, soft robotics and augmented reality. Rendering such electronics soft and stretchable—like human skin—would make them more comfortable to wear, and, through increased contact area, would greatly enhance the fidelity of signals acquired from the skin. Structural engineering of rigid inorganic and organic devices has enabled circuit-level stretchability, but this requires sophisticated fabrication techniques and usually suffers from reduced densities of devices within an array. We reasoned that the desired parameters, such as higher mechanical deformability and robustness, improved skin compatibility and higher device density, could be provided by using intrinsically stretchable polymer materials instead. However, the production of intrinsically stretchable materials and devices is still largely in its infancy: such materials have been reported, but functional, intrinsically stretchable electronics have yet to be demonstrated owing to the lack of a scalable fabrication technology. Here we describe a fabrication process that enables high yield and uniformity from a variety of intrinsically stretchable electronic polymers. We demonstrate an intrinsically stretchable polymer transistor array with an unprecedented device density of 347 transistors per square centimetre. The transistors have an average charge-carrier mobility comparable to that of amorphous silicon, varying only slightly (within one order of magnitude) when subjected to 100 per cent strain for 1,000 cycles, without current–voltage hysteresis. Our transistor arrays thus constitute intrinsically stretchable skin electronics, and include an active matrix for sensory arrays, as well as analogue and digital circuit elements. Our process offers a general platform for incorporating other intrinsically stretchable polymer materials, enabling the fabrication of next-generation stretchable skin electronic devices.

Research and Application of Fiber Bragg Grating Sensor in Geological Disaster Automation Monitoring

Liu Yimin,Wang Jie,Ji Weifeng,Zhou Ce,Chen Wenjun 보안공학연구지원센터 2014 International Journal of Control and Automation Vol.7 No.10

In this paper, fiber grating technology is used for accurately measure stresses, temperature and displacement. The paper introduces the basic principles of FBG technology and the wavelength demodulation method of FBG sensors, and put fiber grating technology into practical engineering projects. The paper design a optical fiber grating real-time automation monitoring system to distributed measure stress, temperature and displacement in geological disaster body, to provide effective technical supports for geological disaster prevention and mitigation.

Two Luminescent Cd(II) Coordination Polymers: Enhancement Activity on Pancreatic Cancer Combined with Biliary Stent Placement and 125I Particles

Jie-Peng Jia,Quan Shao,Ying-Kai Wang,Bo Qian,Wen Zhang,Tao Hu,Ji-Jun Zhang 한국고분자학회 2021 Macromolecular Research Vol.29 No.11

With the reaction between bib ligands, 5-substituted isophthalic acid and Cd(II) ions, we produced two coordination polymers in success, that is, [Cd(5-meo-ip) (bib)0.5]n (2) and [Cd(5-me-ip)(bib)(H2O)]n·n(H2O) (1) (bib is 1,4-bis(imidazoly)butane, 5-meo-H2ip is 5-methoxyisophthalic acid, and 5-me-H2ip is 5-methylisophthalic acid). The luminescent performances and thermal stability of the two compounds were also explored. Their anti-pancreatic cancer activity combined with biliary stent placement and 125I particles was evaluated and the specific mechanism was explored as well. Firstly, after the model construction and compound treatment, the weight and volume of the tumor tissue was measured. Next, the apoptosis level of the cancer cells were evaluated with Annexin V-FITC/PI apoptosis assay.

Effect of the sintering technology on the properties of fired brick from quartz sands

Jie-Guang Song,Fang Wang,Xiao-Bo Bai,Da-Ming Du,Yin-Yan Ju,Ming-Han Xu,Gang-Chang Ji 한양대학교 세라믹연구소 2011 Journal of Ceramic Processing Research Vol.12 No.4

River sands as low grade natural raw materials are used to prepare the fired brick to replace clay fired bricks, which aims to save land resources and use low grade natural resources to realize high cost performance. In this paper, the effect of sintering technology of bricks on their performance is discussed. The compressive strength of fired bricks is first increased and then decreased with an increase in the sintering temperature, the compressive strength of bricks prepared by the isostatic compaction shaping is higher than that of bricks prepared by the plastic shaping under the same conditions. The compressive strength of bricks reaches 28 MPa when sintered at 1150 oC by using a 20MPa isostatic compaction shaping method. The compressive strength of bricks is first increased and then decreased by prolonging the holding time, the compressive strength of bricks reaches 28.9MPa when sintered at 1150 oC for 2 h.

Effect of synthesis conditions on the particle size and morphology of YAG powder

Jie-Guang Song,Fang Wang,Ming-Han Xu,Yin-Yan Ju,Yang-Liang Li,Shi-Bin Li,Gang-Chang Ji 한양대학교 세라믹연구소 2012 Journal of Ceramic Processing Research Vol.13 No.2

Yttrium aluminum garnet (YAG) is currently a widely applied structural and functional material. To prepare highperformance YAG ceramics we prepared pure YAG powder, after calcining the precursor at 1100 ºC, by co-precipitation with ammonia as the precipitant and aluminum nitrate as well as yttrium nitrate as raw materials. The preparation conditions for the YAG precursor were a pH of 9, a titration rate of 10 ml/ minute and a reaction time of 60 minutes. The mean paricle size of the YAG powder was 11ìm. The mean particle size for the YAG powder increased with an increase in the pH and at a higher pH the YAG particles were more irregular in shape. The mean particle size and particle size distribution range of the YAG powder increased with an increase in the titration rate. For the YAG powder with a higher mean particle size, the particle size distribution range was wider but the size of most YAG particles was still small and the YAG particles were nearly spherical.

The effect of a reinforcement phase on the oxidation mechanism of ZrB2-YAG-Al2O3 ceramcis

Jie-Guang Song,Fang Wang,Ming-Han Xu,Shi-Bin Li,Gang-Chang Ji 한양대학교 세라믹연구소 2012 Journal of Ceramic Processing Research Vol.13 No.3

ZrB2 and YAG are widely applied because of some excellent properties, but ZrB2 is easily oxidized in high-temperature air. To make ZrB2 ceramics have a better oxidation resistance, high-density ZrB2-YAG-Al2O3 ceramics were prepared. The effect of a reinforcement phase on the oxidation mechanism of ZrB2-YAG-Al2O3 ceramics is investigated at different high temperature ranges. The results show that the overall tendency of the weight gain of ZrB2-YAG ceramics and ZrB2 ceramics are similar, but the weight gain of ZrB2-YAG ceramics is less than that of ZrB2 ceramics. The weight gain tendency of three types of ceramics are similar below 1000, the weight gain of ZrB2-YAG and ZrB2-YAG-Al2O3 ceramics have a mild tendency between 1000 and 1300, the weight gain tendency of ZrB2-YAG ceramics and ZrB2 ceramics are similar at 1300, however, the weight gain tendency of ZrB2-YAG-Al2O3 ceramics became mild at 1300 due to the Al18B4O33 coating on the ceramic surface. The weight gain rapidly increased for 1h, then the weight gain tendency became mild after 1 h. The weight gain tendency of ZrB2-YAG-Al2O3 ceramics is similar by contrast with ZrB2-YAG ceramics and ZrB2 ceramics for 1 h, the weight gain tendency of ZrB2-YAG-Al2O3 ceramics is extremely mild at a higher oxidation temperature after 1 h. ZrB2 and YAG are widely applied because of some excellent properties, but ZrB2 is easily oxidized in high-temperature air. To make ZrB2 ceramics have a better oxidation resistance, high-density ZrB2-YAG-Al2O3 ceramics were prepared. The effect of a reinforcement phase on the oxidation mechanism of ZrB2-YAG-Al2O3 ceramics is investigated at different high temperature ranges. The results show that the overall tendency of the weight gain of ZrB2-YAG ceramics and ZrB2 ceramics are similar, but the weight gain of ZrB2-YAG ceramics is less than that of ZrB2 ceramics. The weight gain tendency of three types of ceramics are similar below 1000, the weight gain of ZrB2-YAG and ZrB2-YAG-Al2O3 ceramics have a mild tendency between 1000 and 1300, the weight gain tendency of ZrB2-YAG ceramics and ZrB2 ceramics are similar at 1300, however, the weight gain tendency of ZrB2-YAG-Al2O3 ceramics became mild at 1300 due to the Al18B4O33 coating on the ceramic surface. The weight gain rapidly increased for 1h, then the weight gain tendency became mild after 1 h. The weight gain tendency of ZrB2-YAG-Al2O3 ceramics is similar by contrast with ZrB2-YAG ceramics and ZrB2 ceramics for 1 h, the weight gain tendency of ZrB2-YAG-Al2O3 ceramics is extremely mild at a higher oxidation temperature after 1 h.

The effect of the oxidation conditions on the surface microdomains of ZrB2-YAG ultra-high temperature ceramics

Jie-Guang Song,Min-Han Xu,Da-Ming Du,Fang Wang,Shi-Bin Li,Gang-Chang Ji 한양대학교 세라믹연구소 2013 Journal of Ceramic Processing Research Vol.14 No.4

Zirconium diboride is widely applied because of some excellent properties. The effect of the oxidation temperature on the surface microdomain of ZrB2-YAG multi-phase ceramics was studied, it helps to improve the performance of ultra-hightemperature ceramics. The results show the oxidation layer thickness is increased with an increase in the oxidation temperature, the oxidation layer thickness is decreased by increasing the density of multi-phase ceramics at the same oxidation temperature. The ceramic surface shows the (m)ZrO2, YAG, B2O3 and ZrB2 phases below the the oxidation temperature at 1300 ο C, but the ceramic surface do not show the ZrB2 phase above the oxidation temperature at 1300 ο C that is to say, the ZrB2 phase of the ceramic suface is entirely oxidized. The oxidation layer thickness is increased with an increase in the oxidation time, however, the ratio of increasing thickness is less and less. The oxidation layer shows a loose structure during the initial stage of the oxidation, which lacks a barriers for the diffusion of the oxygen.

Effect of raw materials on the properties of ZrB2-YAG-Al2O3 multi-phase ceramics

Jie-Guang Song,Fang Wang,Da-Ming Du,Yin-Yan Ju,Shi-Bin Li,Gang-Chang Ji,Lian-Meng Zhang 한양대학교 세라믹연구소 2014 Journal of Ceramic Processing Research Vol.15 No.2

ZrB2 belongs to a class of ceramics defined ultra-high-temperature ceramics with extremely high melting temperatures, but ZrB2 ceramics is difficultly sintered and easily oxidized. To make ZrB2 ceramics possess the high relative density and the better oxidation resistance. The effects of raw materials on the properties of ZrB2 composite were investigated. YAG and Al2O3 help for the densification of ZrB2 ceramics. Fracture toughness of sintered ceramics with coated powder is higher than that of sintered ceramics with mixed powder. The mechanical property of ZrB2-YAG-Al2O3 materials is higher than that of ZrB2-YAG materials. Oxidation layer thickness of sintered ceramics with coated powder is thinner than that of sintered ceramics with mixed powder. These results show the sintered ZrB2 based multi-phase ceramics with coated microstructure help to increase the mechanical properties and oxidation resistance. The oxidation resistance of ZrB2-YAG-Al2O3 ceramics is better than that of ZrB2-YAG materials.

An Efficient Privacy Preserving Scheme for Distributed Data Aggregation in Smart Grid

Jie Yuan,Yan Wang,Zhicheng Ji 제어·로봇·시스템학회 2022 International Journal of Control, Automation, and Vol.20 No.6

Privacy-preserving data aggregation in smart grids has been intensively studied to balance utility and privacy requirements. Existing contributions usually rely on a trusted aggregator to process electric power data and then apply privacy preservation strategies to protect the aggregate data. However, the privacy of individuals will be revealed once the aggregator is hacked or cannot be trusted. By injecting independent Gaussian noise into the response to the query before performing aggregation, a distributed Gaussian mechanism is designed to eliminate the negative effect of the untrusted aggregator. Equipping the distributed Gaussian mechanism with a post-processing step based on the moving average filtering technique, an efficient privacy-preserving scheme is proposed to improve individual electric power data utility. The experiments conducted on the real-world datasets show that the proposed scheme can improve the utility of electric power data while protecting the privacy of individual data.

Inhibition of Store-Operated Calcium Entry Protects Endothelial Progenitor Cells from H₂O₂-Induced Apoptosis

Wang, Yan-Wei,Zhang, Ji-Hang,Yu, Yang,Yu, Jie,Huang, Lan The Korean Society of Applied Pharmacology 2016 Biomolecules & Therapeutics(구 응용약물학회지) Vol.24 No.4

Store-operated calcium entry (SOCE), a major mode of extracellular calcium entry, plays roles in a variety of cell activities. Accumulating evidence indicates that the intracellular calcium ion concentration and calcium signaling are critical for the responses induced by oxidative stress. The present study was designed to investigate the potential effect of SOCE inhibition on $H_2O_2$-induced apoptosis in endothelial progenitor cells (EPCs), which are the predominant cells involved in endothelial repair. The results showed that $H_2O_2$-induced EPC apoptosis was reversed by SOCE inhibition induced either using the SOCE antagonist ML-9 or via silencing of stromal interaction molecule 1 (STIM1), a component of SOCE. Furthermore, SOCE inhibition repressed the increases in intracellular reactive oxygen species (ROS) levels and endoplasmic reticulum (ER) stress and ameliorated the mitochondrial dysfunction caused by $H_2O_2$. Our findings provide evidence that SOCE inhibition exerts a protective effect on EPCs in response to oxidative stress induced by $H_2O_2$ and may serve as a potential therapeutic strategy against vascular endothelial injury.