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91.
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Ying Chen HuiLi Zhang YuNing Liang YanHua Gao Yongchao Li 《Petroleum Science and Technology》2019,37(7):787-795
In this study, a simple hydrothermal synthesis method was adapted for the preparation of Co-doping Co2+/F-/TiO2 nanotubes photocatalyst, and the micro-nano structure of catalysts prepared by biomimetic technology which makes the catalyst have super-oleophilicity property. Co2+/F-/TiO2 revealed improved photocatalytic performance for denitrification of light oil compared to single TiO2 photocatalysts. The enhance of photocatalytic activity can be attributed to narrowing the band gap, increasing the light response wavelength and exposing more highly active crystal surfaces due to synergistic effects of Co2+ and F? in the photocatalyst. 相似文献
93.
Hongjian Zhu Yingying Chen Yibo Gao Wenxu Liu Zhongpeng Wang Chenchen Cui Wei Liu Liguo Wang 《中国稀土学报(英文版)》2019,37(9):961-969
Codoping approach is an appealing strategy to further improve the catalytic activity of Ce-based catalysts. In the present study,Mn and/or Cu doped ceria solid solutions MnxCuyCe_(1-x-y)O_2,Cu_xCe_(1-x)O_2,Mn_xCe_(1-x)O_2 and pure CeO_2 were prepared by CTAB-assisted hydrothermal method for CO oxidation.XRD, SEM, EDS, BET, Raman, H2-TPR, XPS and in situ DRIFTS techniques were carried out to study the physicochemical properties and to correlate them to the activity. The doped samples maintain the cubic fluorite structure of CeO_2 with high crystallinity and small crystallite size, forming Ce-based solid solutions. The obtained catalysts have large mesoporous structure with average pore size of 10-14 nm. The doped transition metal enhances the oxygen vacancies and improves reducibility of the solids. The synergistic interaction of Mn and Cu codoping induces mo re oxygen vacancies, pro moting the increase of surface adsorbed oxygen and the transfer of bulk oxygen of catalyst, thereby enhancing the catalytic activity for CO oxidation. Besides, the decomposition rate of the carbonate species which is derived from in situ DRIFTS for each catalyst can provide a measure to evaluate its catalytic activity of CO oxidation. 相似文献
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A BFSK and OOK IF base-band circuit is provided to implement the low-IF RF receivers for a dualband MICS/BCC network controller.In order to transfer the massive vital data immediately,the IF circuit is comprised of the fast-settling feed-forward programmable gain amplifier (PGA),a Gm-C complex filter,the fixed gain amplifier (FGA) and a 4-input "quadratic sum" demodulator.A novel auto-switched coarse gain-setting method is adopted in the PGA to enhance the reaction speed and narrow the output signal range.Also the PGA does not suffer the same stability constraint as open-loop topologies.The complex filter fulfills the function of image rejection,in which the center frequency and bandwidth can be adjusted individually.The FGA is used to ameliorate the linearity and the 'quadratic sum' demodulator can reduce the overall power consumption.The designed IF circuit is fabricated with SMIC 0.18/μm CMOS process.The chip area is about 5.36 mm2.Measurement results are given to verify the design goals. 相似文献
96.
Gao Yong-Feng Liu Liu 《International Journal of Control, Automation and Systems》2020,18(6):1392-1398
International Journal of Control, Automation and Systems - In this paper, a new event-triggering scheme is proposed for a class of event-triggered control systems directly based on input-to-state... 相似文献
97.
Zhao Xu Weihong Zhang Tong Gao Jihong Zhu 《Structural and Multidisciplinary Optimization》2020,61(3):923-942
A B-spline multi-parameterization method (MPM) is presented in this paper for topology optimization of thermoelastic structures. As thermoelastic topology 相似文献
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歧口凹陷歧北次凹沙河街组三段页岩油地质特征与勘探突破 总被引:1,自引:0,他引:1
歧口凹陷歧北次凹沙河街组三段(沙三段)湖泛期细粒沉积发育、烃源岩品质好、页岩油资源丰富,但其研究尚处于起步阶段,在沧东凹陷孔店组二段湖相页岩油工业化开发的带动下,落实其勘探前景势成必然。为探究歧北次凹沙三段页岩油的地质特征及勘探潜力,依据F39X1井、QY10-1-1井等多口井的岩心、分析化验、测井资料和录井资料,对沙三段页岩层系的地质特征、页岩油类型与富集模式、甜点的空间分布规律等开展了综合研究。歧北次凹沙三段的矿物组成和岩石类型多样,主要包括灰质白云质页岩、长英质页岩、混合质页岩及微晶白云岩、亮晶生屑白云岩、粉砂岩等;烃源岩的总有机碳(TOC)含量主要分布在1%~3%,以Ⅱ型干酪根为主且指示热演化成熟度的镜质体反射率(Ro)普遍高于0.7%;储集空间主要包括粒间孔、晶间孔、生物体腔孔、有机孔及层理缝、构造(微)缝等;页岩油的超越效应明显(油饱和度指数平均为116.3 mg/g)、荧光显示良好。在歧北次凹沙三段中识别出单一型和夹层型2类页岩油,构建了高TOC滞留型页岩油和低TOC运移型页岩油2种富集模式,并建立了基于油饱和度指数、TOC和脆性指数等多参数的甜点定量评价方法及标准。针对甜点区部署了QY10-1-1水平井,其初期的折算产油量达103.5 t/d,预计可形成亿吨级增储新领域。勘探发现证实歧口凹陷的沙三段细粒岩段具备良好的页岩油勘探潜力。 相似文献