累托石矿物提纯工艺探讨

以B03作分散剂,对湖北省钟祥县杨榨累托石粘土矿物进行了机械搅拌擦洗,使累托石矿物微粒较充分地分散解离,然后通过离心力场的作用,使累托石与水云母、叶腊石、绿泥石、石英等脉石矿物分离,累托石精矿纯度达90％左右,B03的使用为工业生产高纯累托石产品奠定了基础。     

国内外型焦生产工艺及发展前景

介绍了国内外型焦技术的生产工艺、型煤碳化的过程和影响因素,以及国内目前几种碳化窑炉,通过对型焦和焦炭的对比分析,指出洁净型焦生产技术的优势必然会使它在未来具有巨大的发展空间。     

石灰石在煤气化过程中的催化和固硫作用

基于CaO在煤气化中的催化和固硫作用,以及石灰石加热分解的性质,石灰石有可能作为煤气化过程中的催化剂和固硫剂。本文根据国内外对石灰石在煤燃烧和煤气化中作用的研究,从石灰石结构、Ca/C,Ca/S,可能的反应机理等几个方面进行了介绍和分析,并指出需进一步研究的内容。     

直纺长丝工艺中聚酯熔体端羧基值控制的工业研究

本文从工业生产的实践出发对杜邦聚酯技术直接纺工艺中端羧基控制进行了研究。通过对熔体端羧基值对无油长丝端羧基、粘度及纺丝加工影响的分析 ,阐明了聚酯端羧基控制范围 ;通过摸索三个反应釜工艺条件对端羧基值的影响 ,找出了端羧基工业控制的有效途径 ,为同类技术装置生产提供了依据     

Electrochemical performance of nanocrystalline Li3V2(PO4)3/carbon composite material synthesized by a novel sol–gel method

A novel sol–gel method based on V₂O₅·nH₂O hydro-gel was developed to synthesize nanocrystalline Li₃V₂(PO₄)₃/carbon composite material. In this route, V₂O₅·nH₂O hydro-gel, NH₄H₂PO₄, Li₂CO₃ and high-surface-area carbon were used as starting materials to prepare precursor, and the Li₃V₂(PO₄)₃/carbon was obtained by sintering precursor at 750 °C for 4 h in flowing argon. The sol–gel synthesis ensures homogeneity of the precursors and improved reactivity. The sample was characterized by XRD, SEM and TEM. X-ray diffraction results show Li₃V₂(PO₄)₃ sample is monoclinic structure with the space group of P2₁/n. The TEM image indicates that the Li₃V₂(PO₄)₃ particles modified by conductive carbon are about 70 nm in diameter. The Li₃V₂(PO₄)₃/carbon system showed that the discharge capacities in the first and 50th cycle are about 155.3 and 143.6 mAh/g, respectively, in the range of 3.0–4.8 V. The sol–gel method is fit for the preparation of Li₃V₂(PO₄)₃/carbon composite material which may offer some favorable properties for commercial application.     

Dynamic output feedback control of a flexible air-breathing hypersonic vehicle via T–S fuzzy approach

By utilising Takagi–Sugeno (T–S) fuzzy set approach, this paper addresses the robust H_∞ dynamic output feedback control for the non-linear longitudinal model of flexible air-breathing hypersonic vehicles (FAHVs). The flight control of FAHVs is highly challenging due to the unique dynamic characteristics, and the intricate couplings between the engine and fight dynamics and external disturbance. Because of the dynamics’ enormous complexity, currently, only the longitudinal dynamics models of FAHVs have been used for controller design. In this work, T–S fuzzy modelling technique is utilised to approach the non-linear dynamics of FAHVs, then a fuzzy model is developed for the output tracking problem of FAHVs. The fuzzy model contains parameter uncertainties and disturbance, which can approach the non-linear dynamics of FAHVs more exactly. The flexible models of FAHVs are difficult to measure because of the complex dynamics and the strong couplings, thus a full-order dynamic output feedback controller is designed for the fuzzy model. A robust H_∞ controller is designed for the obtained closed-loop system. By utilising the Lyapunov functional approach, sufficient solvability conditions for such controllers are established in terms of linear matrix inequalities. Finally, the effectiveness of the proposed T–S fuzzy dynamic output feedback control method is demonstrated by numerical simulations.     

射流流化床内流体力学行为的模拟研究

以流化床应用为代表的气固流动系统是许多化工过程中的重要组成部分 ,CFD( computational fluid dynamics)方法能够为其优化设计和放大提供所需要的信息 .本文采用双欧拉模型 ,与 Gidaspow等的实验结果进行了对比 ,模拟了二维射流流化床内气泡的形成规律 ,得到了带锥型分布器的流化床内瞬时空隙率和气固相速度分布等流体力学参数 .对锥型分布器流化床的实验结果表明 ,模拟得到的气泡的形状与实验现象相接近 .     

加压下二氧化碳在二甲基甲酰胺中的溶解度研究

本文报道了二氧化碳在二甲基甲酰胺中的溶解度,实验温度分别为15、20、25、30、35、40、45℃,实验压力为207.21—1684.02kPa.并且提出一个考虑了过量熵的、用溶度参数表示的活度系数方程.     

涤纶短纤维生产现状及发展趋势

对目前国内外涤纶短纤维生产的企业规模和工艺技术现状进行了分析比较，并论述了涤纶短纤维生产的经济规模和今后的发展趋势。     

To accelerate shot boundary detection by reducing detection region and scope

Video Shot Boundary Detection (SBD) is the fundamental process towards video summarization and retrieval. A fast and efficient SBD algorithm is necessary for real-time video processing applications. Extensive work has focused on accurate shot boundary detection at the expense of demanding computational costs. In this paper, we propose a fast SBD approach that reduces the computation pixel-wise and frame-wise while still giving satisfactory accuracy. The proposed approach substantially speeds up the computation through reducing both detection region and scope. Color histogram and mutual information are used together to measure the difference between frames. Corner distribution of frames is utilized to exclude most of false boundaries. We conduct extensive experiments to evaluate the proposed approach, and the results show that our approach can not only speed up SBD, but also detect shot boundaries with high accuracy in both Cut (CUT) and Gradual Transition (GT) boundaries.