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排序方式: 共有155条查询结果,搜索用时 15 毫秒
1.
ZhiPeng Wei Shujing Li Yuanbing Li XueSong Li Ruofei Xiang NaNa Xu 《Ceramics International》2018,44(18):22616-22621
To improve the properties of porous alumina ceramics, which were typically prepared by adding pore-forming agents, rice husk (RH) as pore-forming agent was pretreated with zirconia sol. The effects of sol-treatment on the thermal conductivity and compressive strength of the resultant ceramics were characterized. Furthermore, the pore size distribution, pore shape, microstructure, and phase evolution also were studied. The results showed that the RH pretreatment optimizes the microstructure of the ceramic pores. Moreover, complete morph-genetic RH is clearly observed in the pores, which is established as a key factor in improving the properties of the resultant ceramic. The thermal insulation properties are determined to significantly improve, although the thermal conductivity increases slightly with the increment of zirconia sol concentration from 5 to 10?wt%. Meanwhile, after sintering at 1550?°C, the compressive strength is significantly greater for the specimen prepared with 10?wt% zirconia sol-treated RH (65.56?MPa) than that with untreated RH (43.37?MPa). Hence, it was demonstrated that the use of zirconia sol-pretreated RH as a pore-forming agent could enhance the mechanical and thermal insulation properties of porous alumina ceramics. 相似文献
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Xiaofeng Wu Ruofei Jia Jing Pan Jinwen Wang Wei Deng Peng Xiao Xiaohong Zhang Jiansheng Jie 《Advanced functional materials》2021,31(19):2100202
Electron injection plays a crucial role in arousing the double-slope characteristics for p-type organic field-effect transistors (OFETs) with narrow-bandgap organic semiconductors (OSCs). This issue will not only result in the misrepresentation of OFET performance but also may cause device instability, hence impeding their further development in real-world applications. A facile and highly efficient approach is developed to circumvent this issue by implementing modification on the electrode/organic semiconductor interface. An ultrathin layer of wide-bandgap OSC with suitable energy levels is introduced to block the undesirable electron injection. By this means, typical double-slope behaviors and bias stress stability in the p-type OFETs can be significantly improved. Using 2,8-difluoro-5,11-bis(triethylsilylethynyl) anthradithiophene-based OFETs the double-slope behaviors of as-fabricated devices are effectively converted to near-ideal behaviors after modification, leading to a dramatic improvement of average reliability from 65.11% to 91.76%. Furthermore, the positive drift of transfer curves under prolonged bias stress is also successfully suppressed. This strategy demonstrates good universality and can provide a new guideline for the fabrication of OFETs with ideal behaviors. 相似文献
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Ruofei Hu Qingzeng Zhu Weikai Chen Hui Liu Bingjian Yao Jinhua Zhan Jingcheng Hao Charles C. Han 《Polymer》2012,53(2):267-271
Ordered dichloro-biphenylene-bridged silsesquioxanes are fabricated by interfacial polymerization at the aqueous/organic phase interface, which involves hydrogen bonding and aromatic π–π stacking interaction, which are responsible for the preferential orientation of the organic bridged units. The high-resolution transmission electronic microscopy images and wide angle X-ray powder diffraction patterns reveal the well-ordered features with lamellar spacings in the hybrid silsesquioxanes. Fluorescence spectra and molecular simulation verify the possibility of ordered structure formation. A general model is developed for the formation of ordered 3,3′-dichloro-biphenylene-bridged silsesquioxanes by interfacial polymerization. This method should offer a convenient avenue for the preparation of highly ordered hybrid network materials. 相似文献
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Jing Wang Guangfei Liu Hong Lu Ruofei Jin Jiti Zhou 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》2013,88(5):970-974
BACKGROUND: Traditional treatment systems failed to achieve efficient degradation of anthraquinone dye intermediates at high loading. Thus, an airlift internal loop reactor (AILR) in combination with the TiO2‐photocatalytic ozonation (TiO2/UV/O3) process was investigated for the degradaton of 1‐amino‐ 4‐bromoanthraquinone‐2‐ sulfonic acid (ABAS). RESULTS: The AILR using Sphingomonas xenophaga as inoculum and granular activated carbon (GAC) as biocarrier, could run steadily for 4 months at 1000 mg L?1 of the influent ABAS. The efficiencies of ABAS decolorization and chemical oxygen demand (COD) removal in AILR reached about 90% and 50% in 12 h, respectively. However, when the influent ABAS concentration was further increased, a yellow intermediate with maximum absorbance at 447 nm appeared in AILR, resulting in the decrease of the decolorization and COD removal efficiencies. Advanced treatment of AILR effluent indicated that TiO2/UV/O3 process more significantly improved the mineralization rate of ABAS bio‐decolorization products with over 90% TOC removal efficiency, compared with O3, TiO2/UV and UV/O3 processes. Furthermore, the release efficiencies of Br? and SO42? could reach 84.5% and 80.2% during TiO2/UV/O3 treatment, respectively, when 91.5% TOC removal was achieved in 2 h. CONCLUSION: The combination of AILR and TiO2/UV/O3 was an economic and efficient system for the treatment of ABAS wastewater. © 2012 Society of Chemical Industry 相似文献
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Accurate prediction of magmatic intrusion into a coal bed is illustrated using the method of seismic spectral decomposition. The characteristics of coal seismic reflections are first analyzed and the effect of variable time windows and domain frequencies on the spectral decomposition are examined. The higher domain frequency of coal bed reflections using the narrower STFT time window, or the smaller ST scale factor, are acceptable. When magmatic rock intrudes from the bottom of the coal bed the domain frequency of the reflections is decreased slightly, the frequency bandwidth is narrowed correspondingly, and the response from spectral decomposition is significantly reduced. Intrusion by a very thin magmatic rock gives a spectral decomposition response that is just slightly less than what is seen from a normal coal bed. Results from an actual mining area were used to validate the method. Predicting the boundary of magmatic intrusions with the method discussed herein was highly accurate and has been validated by observations from underground mining. 相似文献
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双源面波地震勘探在煤层采空区探测中的应用 总被引:1,自引:1,他引:0
面波勘探具有简便、快速的优点,在陕北柠条塔井田煤层采空区探测中取得良好的地质效果。利用面波的特征反映不仅可以通过单炮记录进行煤层采空区初步解释,还可通过剖面波场特征频谱特征以及频散曲线进行煤层采空区综合解释。 相似文献
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Deep Web网站采用Ajax技术后使得获取其数据信息更加困难。查询接口处理是获取Deep Web数据的关键步骤,针对采用Ajax技术的Deep Web查询接口,建立Ajax分析处理模型,解决传统爬虫无法完成表单提交的困难,从而获取到更多的Deep Web数据。实验结果证实,该方法是有效的。 相似文献