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Co-conversion of methanol and n-hexane into aromatics using intergrown ZSM-5/ZSM-11 as a catalyst

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Frontiers of Chemical Science and Engineering 2020年第5期14卷 783-792页

作者： Shumei wei Yarong Xu Zhaoyang Jin Xuedong Zhu UNILAB State Key Laboratory of Chemical EngineeringEast China University of Science and TechnologyShanghai 200237China Research Institute of Urumqi Petrochemical Company Petrochina Company LimitedUrumqi 830019China

The conversion of n-hexane and methanol into value-added aromatic compounds is a promising method for their industrially relevant *** this study,intergrown ZSM-5/ZSM-11 crystals were synthesized and their resulting catalytic performance was investigated and compared to those of the isolated ZSM-5 and ZSM-1I *** physicochemical properties of ZSM-5/ZSM-l1 intergrown zeolite were analyzed using X-ray diffrac-tion,N2 isothermal adsorption-desorption,the tempera-ture-programmed desorption of ammonium,scanning clectron microscopy,Fourier transform infrared spectra of adsorbed pyridine,and nuclear magnetic resonance of 27AI,and compared with those of the ZSM-5 and ZSM-11 *** catalytic performances of the materials were evaluated during the co-feeding reaction of methanol and n-hexane under the fixed bed conditions of 400℃,0.5 MPa(N2),methanol:n-hexane=7:3(mass ratio),and weight hourly space velocity=1 h 1(methanol).Com-pared to the ZSM-5 and ZSM-11 zeolites,the ZSM-5/ZSM-11 zeolite exhibited the largest specific surface area,a unique crystal structure,moderate acidity,and suitable Brensted/Lewis acid *** evaluation results showed that ZSM-5/ZSM-11 catalyst exhibited better catalytic reactivity than the ZSM-5 and ZSM-11 catalysts in terms of methanol conversion rate,n-hexane conversion rate,and aromatic *** outstanding catalytic property of the intergrown ZSM-5/ZSM-11 was attributed to the enhanced diffusion associated with its unique *** benefit of using zeolite intergrowth in the co-conversion of methanol and alkanes offers a novel route for future catalyst development.

关键词： ZSM-5/ZSM-11 methanol w-hexane cofeeding aromatics

Computational Path Planner for Product Assembly in Complex Environments

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Chinese Journal of Mechanical Engineering 2013年第2期26卷 282-292页

作者： SHANG wei LIU Jianhua NING Ruxin LIU Mi School of Mechanical Engineering Beijing Institute of Technology

Assembly path planning is a crucial problem in assembly related design and manufacturing processes. Sampling based motion planning algorithms are used for computational assembly path planning. However, the performance of such algorithms may degrade much in environments with complex product structure, narrow passages or other challenging scenarios. A computational path planner for automatic assembly path planning in complex 3D environments is presented. The global planning process is divided into three phases based on the environment and specific algorithms are proposed and utilized in each phase to solve the challenging issues. A novel ray test based stochastic collision detection method is proposed to evaluate the intersection between two polyhedral objects. This method avoids fake collisions in conventional methods and degrades the geometric constraint when a part has to be removed with surface contact with other parts. A refined history based rapidly-exploring random tree （RRT） algorithm which bias the growth of the tree based on its planning history is proposed and employed in the planning phase where the path is simple but the space is highly constrained. A novel adaptive RRT algorithm is developed for the path planning problem with challenging scenarios and uncertain environment. With extending values assigned on each tree node and extending schemes applied, the tree can adapts its growth to explore complex environments more efficiently. Experiments on the key algorithms are carried out and comparisons are made between the conventional path planning algorithms and the presented ones. The comparing results show that based on the proposed algorithms, the path planner can compute assembly path in challenging complex environments more efficiently and with higher success. This research provides the references to the study of computational assembly path planning under complex environments.

关键词： assembly path planning motion planning stochastic collision detection rapidly-exploring random tree adaptive RRT

Influence of Na^+,K^+,Mg^(2+),Ca^(2+),and Fe^(3+) on filterability and settleability of drilling sludge

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Chinese Journal of Chemical Engineering 2017年第5期25卷 658-664页

作者： Liyan Liu Hao Yan wei Tan Guorui Zhu School of Chemical Engineering and Technology Tianjin University

Solid–liquid separation is a vital step in drilling sludge disposal, and the filterability and settleability of drilling sludge are the main evaluating indicators for the separation process. The influence of Na^+,K^+,Mg^(2+),Ca^(2+),and Fe^(3+) on drilling sludge filterability and settleability was investigated in our research. The water content,filtration rate, supernatant volume and supernatant turbidity were measured to evaluate the filterability and settleability of drilling sludge. Meanwhile, the zeta potential, specific surface area of sludge flocs, particle size distribution and Fourier-transformed infrared spectra were employed to clarify the influencing *** experimental results showed that the filterability and settleability of drilling sludge were related to concentration and types of cations. Mg^(2+),Ca^(2+),and Fe^(3+) performed better than Na^+, K^+, and the cations with smaller hydrated radius got superior solid–liquid separation behavior at same valence. Finally, the spectra indicated that no chemical adsorption occurred between inorganic cations and drilling sludge flocs. The variation of surface charge and flocs growth after adding different inorganic cations were the reasons for the changes of the filterability and settleability.

关键词： Drilling sludge Inorganic cations Filtration Settleability Adsorption

Interannual modulation of intraseasonal sea level variability along the southern coast of Java

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Science China Earth Sciences 2018年第1期61卷 1-12页

作者： CAO GuoJiao HE YiJun wei ZeXun XU TengFei School of Marine Sciences Nanjing University of Information Science & Technology Nanjing 210044 China First Institute of Oceanography State Oceanic Administration Qingdao 266061 China Laboratory for Regional Oceanography and Numerical Modeling Qingdao National Laboratory for Marine Science and Technology Qingdao 266237 China jiangsu Research Center for Ocean Survey and Technology Nanjing 210044 China

The intraseasonal variability(ISV) of sea level anomalies(SLAs) along the southern coast of Java and its interannual modulation were studied based on a gridded SLA product produced from the Archiving, Validation, and Interpretation of Satellite Oceanography dataset. This ISV is induced by the propagation of intraseasonal Kelvin waves derived from the central equatorial Indian Ocean(EIO). Wavelet analysis and empirical mode decomposition of intraseasonal SLAs along the southern coast of Java showed interannual variability, with weaker ISV events during El Ni years and positive Indian Ocean Dipole(IOD) years than during normal years. This interannual modulation of the ISV is influenced by the El Ni-Southern Oscillation teleconnection via the Walker Circulation and eastern Indian Ocean upwelling connected to IOD events. The anomalously weaker Walker Circulation during El Ni events generates anomalous surface easterlies over the central-eastern tropical Indian Ocean that produce upwelling Kelvin waves in the EIO and offshore water transport along the southern coasts of Sumatra and Java, resulting in negative SLAs along the southern coast of Java. These negative SLAs damp the positive SLAs induced by the eastward propagation of downwelling Kelvin waves from the central EIO during the following March–May of El Ni years. Similar features of SLAs and sea surface wind anomalies also occur during positive IOD years. Consequently, the sea level ISV along the southern coast of Java is weaker in El Ni and positive IOD years.

关键词： Intraseasonal variability Sea level Interannual variability Kelvin waves Indian Ocean

Optimal Constrained Self-learning Battery Sequential Management in Microgrid Via Adaptive Dynamic Programming

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IEEE/CAA Journal of Automatica Sinica 2017年第2期4卷 168-176页

作者： Qinglai wei Derong Liu Yu Liu Ruizhuo Song IEEE State Key Laboratory of Management and Control for Complex Systems Institute of AutomationChinese Academy of Sciences University of Chinese Academy of Sciences School of Automation and Electrical Engineering University of Science and Technology Beijing Institute of Automation Chinese Academy of Sciences

This paper concerns a novel optimal self-learning battery sequential control scheme for smart home energy systems. The main idea is to use the adaptive dynamic programming U+0028 ADP U+0029 technique to obtain the optimal battery sequential control iteratively. First, the battery energy management system model is established, where the power efficiency of the battery is considered. Next, considering the power constraints of the battery, a new non-quadratic form performance index function is established, which guarantees that the value of the iterative control law cannot exceed the maximum charging/discharging power of the battery to extend the service life of the battery. Then, the convergence properties of the iterative ADP algorithm are analyzed, which guarantees that the iterative value function and the iterative control law both reach the optimums. Finally, simulation and comparison results are given to illustrate the performance of the presented method. © 2017 Chinese Association of Automation.

关键词： Adaptive control systems Automation Battery management systems Control theory Electric batteries Energy management Energy management systems Intelligent buildings Iterative methods Number theory Secondary batteries

DBS imaging based on Keystone transform

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Journal of Systems Engineering and Electronics 2012年第3期23卷 342-348页

作者： Jing Tian wei Cui Lin Ma Siliang Wu Radar Research Institute Beijing Institute of TechnologyBeijing 100081E R.China

To correct the range walk through resolution cell in Doppler beam sharpening （DBS） imaging, a new DBS imaging algorithm based on Keystone transform is proposed. Without the exact values of the movement parameters and the look angle of the radar platform in the multi-targets environment, a linear trans- form on the received data is employed to correct different range walk values accurately under the condition of Doppler frequency ambiguity in this algorithm. This method can realize the cohe- rent integration in azimuth dimension and improve the azimuth resolution. In order to reduce the computational burden, a fast implementation of Keystone transform is used. Theoretical anal- ysis and simulation results demonstrate the effectiveness of the new algorithm. And through comparing the computational load of the fast implementation with several other algorithms, the real-time processing ability of the proposed algorithm is superior to that of other algorithms.

关键词： Doppler beam sharpening (DBS) Keystone transform range walk coherent integration.

Collecting and analyzing key-value data under shuffled differential privacy

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Frontiers of Computer Science 2023年第2期17卷 241-243页

作者： Ning WANG wei ZHENG Zhigang WANG Zhiqiang wei Yu GU Peng TANG Ge YU Faculty of Information Science and Engineering Ocean University of ChinaQingdao 266100China School of Computer Science and Engineering Northeastern UniversityShenyang 110819China Key Lab of Cryptologic Technology and Information Security Ministry of EducationShandong UniversityQingdao 266200China School of Cyber Science and Technology Shandong UniversityQingdao 266200China

1 Introduction Key-value data,as NoSQL data widely used in recent years,has been frequently collected and used for analysis in major websites and mobile *** frequency distribution estimation on the key domain,as well as the mean estimation of values associated with the same key,are crucial and worth billion dollars in the ***,in real applications,the key-value records are submitted by terminal devices of different *** collecting the information from users may pose serious risks on personal *** the other hand,the emerging shuffled differential privacy(SDP)model[1]is proposed to collect sensitive data from users.

关键词： NoSQL app value

Relationship between the specific surface area of rust and the electrochemical behavior of rusted steel in a wet–dry acid corrosion environment

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International Journal of Minerals,Metallurgy and Materials 2017年第1期24卷 55-63页

作者： wei Liu Qing-he Zhao Shuan-zhu Li Corrosion and Protection Center Institute for Advanced Materials and TechnologyUniversity of Science and Technology BeijingBeijing 100083China

The relationship between the specific surface area（SSA） of rust and the electrochemical behavior of rusted steel under wet-dry acid corrosion conditions was investigated. The results showed that the corrosion current density first increased and then decreased with increasing SSA of the rust during the corrosion process. The structure of the rust changed from single-layer to double-layer, and the γ-FeOOH content decreased in the inner layer of the rust with increasing corrosion time; by contrast, the γ-FeOOH content in the outer layer was constant. When the SSA of the rust was lower than the critical SSA corresponding to the relative humidity during the drying period, condensed water in the micropores of the rust could evaporate, which prompted the diffusion of O_2 into the rust and the following formation process of γ-FeOOH, leading to an increase of corrosion current density with increasing corrosion time. However, when the SSA of the rust reached or exceeded the critical SSA, condensate water in the micro-pores of the inner layer of the rust could not evaporate which inhibited the diffusion of O_2 and decreased the γ-FeOOH content in the inner rust, leading to a decrease of corrosion current density with increasing corrosion time.

关键词： steel corrosion rust specific surface area electrochemical behavior polarization curves

Encoding-Decoding-Based Control and Filtering of Networked Systems： Insights, Developments and Opportunities

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IEEE/CAA Journal of Automatica Sinica 2018年第1期5卷 3-18页

作者： Zidong Wang Licheng Wang Shuai Liu Guoliang wei Department of Computer Science Brunel Univer-sity London Uxbridge Middlesex UB8 3PH United Kingdom Department of Control Science and Engineering University of Shanghai for Science and Technology Shanghai 200093 China University of Shanghai for Science and Technology Shanghai 200093 China IEEE

In order to make the information transmission more efficient and reliable in a digital communication channel with limited capacity, various encoding-decoding techniques have been proposed and widely applied in many branches of the signal processing including digital communications, data compression,information encryption, etc. Recently, due to its promising application potentials in the networked systems(NSs), the analysis and synthesis issues of the NSs under various encoding-decoding schemes have stirred some research attention. However, because of the network-enhanced complexity caused by the limited network resources, it poses new challenges to the design of suitable encoding-decoding procedures to meet certain control or filtering performance for the NSs. In this survey paper, our aim is to present a comprehensive review of the encoding-decodingbased control and filtering problems for different types of ***, some basic introduction with respect to the coding-decoding mechanism is presented in terms of its engineering insights,specific properties and theoretical formulations. Then, the recent representative research progress in the design of the encodingdecoding protocols for various control and filtering problems is discussed. Some possible further research topics are finally outlined for the encoding-decoding-based NSs.

关键词： Encoding-decoding-based communication mechanism encoding-decoding-based control encoding-decodingbased state estimation networked systems