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971.
Wearable human–computer interaction equipment is a common technology, which can improve the comfort, convenience, and safety of the human body, and also can monitor human health. The flexible and wearable tensile sensor can be conveniently installed on clothes or directly connected to the body. This provides a convenient, timely, and portable solution for the detection of human motion. Therefore, wearable electronic equipment is gaining more attention. In this paper, a highly stretchable, flexible, and sensitive strain sensor which is based on multi-walled carbon nanotubes/Ecoflex nanocomposites is reported. A monofilament tensile sensor obtains good linearity (10.77%), low hysteresis (1.63%), good stability (6000 cycles under 100% strain), and ultra-high strain range (ε = 1300%). This ultra-stretchable sensor has potential applications in human motion monitoring, medical rehabilitation, health monitoring, human–computer interaction, and soft robots.  相似文献   
972.
The introduction of metallic fillers to polymers via the photopolymerization approach can endow the composite materials with some unique properties, but the relevant research is still scarce due to the issue of light penetration and inner filter effect. Herein, for the first time the fabrication of photocomposites based on fine iron powder (i.e., a typical kind of metallic filler) is reported in this work. The free radical polymerization of two different acrylate monomers, poly(ethylene glycol) diacrylate and trimethylolpropane triacrylate, is performed in the presence of iron filler under mild conditions (i.e., light emitting diode (LED)@405 nm irradiation at room temperature under air). And the real-time Fourier transform infrared spectroscopy reveals remarkable photopolymerization kinetics of acrylates with high final conversions and fast polymerization rates despite the increasing contents of iron filler in the composites. Interestingly, the 3D printing technique is applied to the iron filler-based composites to produce tridimensional patterns with excellent spatial resolution. This work not only paves the way for the investigation of photocomposites based on metallic fillers through photochemical methods, but also broadens the potential application prospects.  相似文献   
973.
电网故障处置预案是电网故障处置的重要参考,对电网故障处置预案文本中各类电力设备、名称编号等细粒度的关键实体信息进行抽取,是实现计算机学习理解预案内容并进一步支撑故障处置智能化的重要基础。文中提出一种基于深度学习的电网故障处置预案文本命名实体识别技术,首先采用字向量表征预案文本,然后将注意力机制以及双向长短期记忆网络相结合,有所侧重地提取实体词深层字符特征,最后采用条件随机场求解最优序列化的标注。算例表明:文中所提预案文本命名实体识别模型不依赖人工特征,能够自动高效地提取文本特征,准确识别预案文本中细粒度的实体词,满足预案文本中关键实体信息精确定位和识别的要求。  相似文献   
974.
A multifunctional thiophene-based covalent triazine framework (TTPATTh) with triphenylamine as core is synthesized by Friedel–Crafts reaction of cyanuric chloride with thienyl derivative for the first time. The yield of TTPATTh (99.59%) is far higher than that of the carbazole-based CTF (TTPATCz, 47.03%). TTPATTh and TTPATCz possess high BET surface areas with 1235 and 2501 m2 g–1 as well as high pore volumes with 1.60 and 2.23 cm3 g–1, respectively. TTPATTh and TTPATCz have high thermal stability with high thermal decomposition temperatures of 514 and 598 °C in nitrogen atmosphere. With the introduction of triazine rings, the fluorescence sensing sensitivities of TTPATTh and TTPATCz to picric acid and iodine are improved significantly. Especially for TTPATTh, the Ksv values reach 5.95 × 105 and 1.61 × 104 L mol–1, and LODs reach 1.02 × 10–12 and 1.86 × 10–12 mol L–1. To the best of the knowledge, this is the most sensitive value among thiophene-based porous organic polymers to PA and I2. Furthermore, TTPATTh and TTPATCz can also adsorb iodine in vapor phase, cyclohexane solution and aqueous solution, and release iodine by heating or in ethanol solution. The efficiency of controlling the release of iodine is higher than that in ethanol.  相似文献   
975.
Bcl-2 and Mcl-1, the two arms of the anti-apoptotic Bcl-2 family proteins, have been identified as key regulators of apoptosis and effective therapeutic targets of cancer. However, no small-molecular probe is capable of profiling and visualizing both Bcl-2 and Mcl-1 simultaneously in situ. Herein, we report a multifunctional molecular probe (BnN3-OPD-Alk) by a “three-in-one” molecular designing strategy, which integrated the Bcl-2/Mcl-1 binding ligand, fluorescent reporter group and photoreactive group azido into the same scaffold. BnN3-OPD-Alk exhibited sub-micromolar affinities to Bcl-2/Mcl-1 and bright green self-fluorescence. It was then successfully applied for Bcl-2/Mcl-1 labeling, capturing, enriching, and bioimaging both in vitro and in cells. This strategy could facilitate the precise early diagnosis and effective therapy of dual Bcl-2/Mcl-1-related diseases.  相似文献   
976.
There is a growing demand to develop epoxy resins (EP) with smoke suppression as well as satisfactory flame retardancy. Herein, bio-based cobalt alginate is successfully fabricated and incorporated into EP to prepare EP/Cobalt Alginate composites with better fire safety performance. The addition of cobalt alginate reduces the thermal-decomposition rate, temperature at maximum weight-loss rate of EP, whereas obviously improves the thermal stabilities at a higher temperature range. Furthermore, the addition of cobalt alginate substantially reduces the fire hazard of EP, resulting in 56.2% reduction in peak heat release rate, as well as 17.8% and 56.3% reduction in total smoke production and peak smoke production rate, respectively, compared with EP matrix. Moreover, the presence of cobalt alginate increases smoke-suppressant properties, according to the smoke density test. Additionally, the incorporation of cobalt alginate has no obviously destructive effect on the mechanical properties of EP, while EP/Cobalt Alginate-3 exhibits a 27.0% improvement in impact strength. In prospective, this study may provide a significant method for producing eco-friendly flame retardant EP.  相似文献   
977.
A hierarchical porous cenosphere/geopolymer composite foam (FHCs/KGP) was fabricated by the simultaneous incorporation of O2 pore from hydrogen peroxide and cenosphere filler addition. Effects of both H2O2 content and high-temperature treatment on the microstructure, porosity and strength of porous FHCs/KGP foams were investigated systematically. The obtained FHCs/KGP foams showed typical amorphous structure and desirable porosity from 65 to 82%. The composites could crystallize in situ to FHCs/leucite foams above 1000℃. Compression strength of the FHCs/leucite foams showed a maximum value of 5 ± 0.3 MPa when treated at 1000°C. The improvement of mechanical properties for the composite foams was attributed to crack deflection, fractured microspheres and the good bond between the FHCs and matrix. This study could open opportunities to employ cellular foams as alternatives in structure and filtration applications.  相似文献   
978.
A 3D architecture carbon fiber preform, specifically fine-woven cloth and punctured felt preform, is used to manufacture a novel advanced Cf/C-SiC-ZrC composite. The composite matrix is produced by chemical vapor infiltration (CVI) plus precursor infiltration and pyrolysis (PIP) process and finalized by using a chemical vapor deposition (CVD) of SiC coating to make the final density of the material reach 1.95 g/cm3. The organic precursors of SiC and ZrC have a weight ratio of 4:1 in a xylene solute. The composite mechanical properties, such as tensile, compression, bending, shear, and Z-direction load bearing, are introduced under analysis to find possible applications for the composite. What is more, scanning electron microscope (SEM) images are employed to illustrate the failure behavior of the ceramic composite. The results showed that the punctured filament tows will be beneficial, not only for the composite to withstand compression force up to 308.6 MPa and shear strength to 18.14 MPa but also for the alternatively stacked weave piles and short fiber layers to support the punctured bundles, as well as to hold the composite structure under mechanical forces from different orientations, which is believed to reinforce the ceramic matrix for some high pressure and severe ablation applications.  相似文献   
979.
Journal of Inorganic and Organometallic Polymers and Materials - In recent decades, straw waste is the major byproduct around agriculture that has become one of the factors of environmental...  相似文献   
980.
Journal of Inorganic and Organometallic Polymers and Materials - The original version of this article unfortunately contained mistakes. In line 9 of the abstract, 5% should read as 2%. The...  相似文献   
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