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991.
In this study, we propose the fabrication of sol-gel composite-based flexible and transparent synaptic transistors on polyimide (PI) substrates. Because a low thermal budget process is essential for the implementation of high-performance synaptic transistors on flexible PI substrates, microwave annealing (MWA) as a heat treatment process suitable for thermally vulnerable substrates was employed and compared to conventional thermal annealing (CTA). In addition, a solution-processed wide-bandgap amorphous In-Ga-Zn (2:1:1) oxide (a-IGZO) channel, an organic polymer chitosan electrolyte-based electric double layer (EDL), and a high-k Ta2O5 thin-film dielectric layer were applied to achieve high flexibility and transparency. The essential synaptic plasticity of the flexible and transparent synaptic transistors fabricated with the MWA process was demonstrated by single spike, paired-pulse facilitation, multi-spike facilitation excitatory post-synaptic current (EPSC), and three-cycle evaluation of potentiation and depression behaviors. Furthermore, we verified the mechanical robustness of the fabricated device through repeated bending tests and demonstrated that the electrical properties were stably maintained. As a result, the proposed sol-gel composite-based synaptic transistors are expected to serve as transparent and flexible intelligent electronic devices capable of stable neural operation. 相似文献
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994.
Fabrication of asymmetrically superhydrophobic cotton fabrics via mist copolymerization of 2,2,2‐trifluoroethyl methacrylate 下载免费PDF全文
GuangHui Xi WanChao Fan Lu Wang XiangDong Liu Takeshi Endo 《Journal of polymer science. Part A, Polymer chemistry》2015,53(16):1862-1871
We report here a simple strategy for fabricating asymmetrically superhydrophobic cotton fabric via a mist copolymerization of three monomers, 2,2,2‐trifluoroethyl methacrylate (TFMA), 2‐isocyanatoethyl methacrylate (IEM), and divinylbenzene (DVB). The copolymer layer on the cotton surface was confirmed by X‐ray photoelectron spectroscopy (XPS) analysis and attenuated total reflection (ATR) accessory, and the nanoscale hierarchical structures in the polymeric layer were demonstrated by observation of field emission scanning electron microscope (FE‐SEM). Surface characterization reveals that the modified surface is superhydrophobic, but the opposite side of the modified cotton fabric has the hydrophilic nature of cotton. More experimental data suggest that the good water adsorptivity and vapor transmissibility of the original cotton fabric were inherited after the surface modification. These properties are of great significance in textile and medical applications. © 2015 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2015 , 53, 1862–1871 相似文献
995.
应用超声萃取-高效液相色谱法测定棉织物中5种荧光增白剂的含量。棉织物样品在40℃温度下用二甲基甲酰胺-水(70+30)混合液超声提取20min。提取液按仪器工作条件进行色谱测定。分离中用Agilent Eclipse XDB-C18色谱柱为固定相,用乙腈和10mmol·L-1乙酸铵溶液以不同比例混合后作为流动相进行梯度洗脱。用二极管阵列检测器测定。5种荧光增白剂的质量浓度均在0.5~200.0mg·L-1范围内与其峰面积呈线性关系,方法的检出限(3S/N)在0.05~0.10mg·L-1之间,测定下限(10S/N)在1.2~2.1mg·kg-1之间。以空白样品为基体进行加标回收试验,所得回收率在76.5%~103%之间,相对标准偏差(n=6)在2.6%~7.1%之间。 相似文献
996.
High-electromagnetic-shielding cotton fabric (CF) was prepared using carboxyl-functionalized multiwall carbon nanotubes (MWCNTs-COOH)/nickel–phosphorus (Ni-P) electroless plating. Firstly, MWCNTs-COOH was loaded on CF used to chelate the metal catalyst followed by electroless plating to impart outstanding electrical conductivity and electromagnetic shielding properties. The intermediate MWCNTs-COOH layer not only improves the bonding strength via the chelating effect, but also can be used as a conductive material. This synergistic action of MWCNTs-COOH and Ni-P layer can work together to improve the electromagnetic interference shielding performance. The features of Ni-P/MWCNTs-COOH/CF were characterized using scanning electron microscopy, energy-dispersive spectroscopy, X-ray photoelectron spectroscopy and X-ray diffraction. The resulting Ni-P/MWCNTs-COOH/CF fabrics show high surface resistance of 1.66 Ω sq−1 and robust electromagnetic shielding effectiveness of 40.2 dB. Furthermore, benefiting from the strong interface interaction, the as-prepared composite fabrics retain stable performances after undergoing a series of physical and chemical tests, confirming promising practical applications even under harsh conditions. 相似文献
997.
Dr. Shuai Wang Shuo Huang Minjie Yao Yan Zhang Prof. Zhiqiang Niu 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(29):11898-11905
The reversible capacity of AlCl4− intercalation/de-intercalation in conventional cathodes of aluminum-ion batteries (AIBs) is difficult to improve due to the large size of AlCl4− anions. Therefore, it is highly desirable to realize the intercalation/de-intercalation of smaller Al-based ions. Here, we fabricated polyaniline/single-walled carbon nanotubes (PANI/SWCNTs) composite films and protonated the PANI nanorods. The protonation endows PANI with more active sites and enhanced conductivity. Hyper self-protonated PANI (PANI(H+)) exhibits reversible AlCl2+ intercalation/de-intercalation during the discharge/charge process. As a result, the discharge capacity of the Al/PANI(H+) battery is twice as high as that of the initial composite films. PANI(H+)@SWCNT electrodes also have a stable cycling life with only 0.003 % capacity decay per cycle over 8000 cycles. Owing to the excellent mechanical properties, PANI(H+)@SWCNT composite films can act as the electrodes of flexible AIBs. 相似文献
998.
Desislava Staneva Evgenia Vasileva-Tonkova Stanislava Yordanova Rositsa Kukeva Radostina Stoyanova 《International Journal of Polymer Analysis and Characterization》2020,25(5):374-384
Abstract Poly(propylene imine) dendrimers from first and third generation modified with 1,8-naphthalimide units and their Cu(II) complexes have been characterized by fluorescence and EPR spectroscopy. Cotton fabric has been modified with these dendrimers and their color characteristics were determined. The antimicrobial activity of dendrimer ligands and their Cu(II) complexes in solution and after their deposition on a cotton fabric was investigated. Good antibacterial effect of dendrimer ligands has been obtained, which is enhanced at their Cu(II) complexes. After their deposition on cotton fabric metallodendrimers exhibit good antibiofilm activity. 相似文献
999.
ABSTRACT Twenty novel azobenzene liquid crystal micromolecular compounds named ω-[4-(p-substituted azobenzeneoxy carbonyl]acid (X-ABCnA) have been designed and synthesised, followed by studies on the thermal performance and mesomorphic properties of the compounds. The liquid crystal compounds were divided into five homologous series based on the terminal substituents R (R = CH3O, CH3, H, Cl, NO2). In each series, the number of carbons on flexible chain was 4, 6, 8 and 10, respectively. Fourier-transform infrared, proton nuclear magnetic resonance and elementary analysis demonstrated that the structure of the synthesised azobenzene liquid crystal compounds was consistent with the molecular design. The mesomorphic properties were tested, analysed and characterised by using differential scanning calorimetry and polarised optical microscopy. The melting transition (T m) of all the compounds in homologous series with different substituents appeared to decrease with the increase of carbon numbers on flexible chains. The same held true for the temperature of isotropic-mesophase/crystalline transition. The compounds with stronger polarity of terminal substituents were more likely to form broader mesogenic ranges. The liquid crystal compounds discussed in this work can be regarded as a reference for the synthesis of mesogenic arms participating in the synthesis of novel multi-arm liquid crystalline macromolecules and polymers. 相似文献
1000.
以碳纤维作为柔性衬底和电极材料,通过溶胶凝胶法在其表面镀覆TiO2阻变活性层,进而通过“十”字搭接制备成柔性纤维忆阻器(TiO2@Cf)。采用X射线衍射、扫描电子显微镜、X射线光电子能谱等测试手段对TiO2@Cf结构进行表征并对其忆阻特性及阻变机理进行研究。结果表明:碳纤维上的TiO2涂层为锐钛矿型晶体结构,其氧空位的浓度约为19.5%;制备的TiO 2@Cf柔性忆阻器为突变型忆阻器,其高低阻态阻值开关比可达104;经过疲劳耐受性测试,忆阻器件的高低阻态开关比稳定在2个数量级左右。TiO2@Cf忆阻器的机理表现为:在高阻态和低阻态时是以欧姆导电为主导的载流子输运机制,其阻态转变机制与氧空位导电细丝的形成和断裂有关。制备的TiO2@Cf柔性忆阻器在一定程度上具有柔性弯曲变形,同时满足可编织、穿戴等功能。 相似文献