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Effect of preparation methods on the hydrocracking performance of NiMo/Al_(2)O_(3) catalysts

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Chinese Journal of Chemical Engineering 2021年第4期34卷 224-230页

作者： Jiake Yang Tongjiu zuo Jiangyin Lu Key Laboratory of Oil&Gas Fine Chemicals Ministry of EducationCollege of Chemistry and Chemical EngineeringXinjiang UniversityUrumqi 830046China

In this work,NiMo catalysts with various contents of MoO_(3)were prepared through incipient wetness impregnation by a twostep method(NMxA)and onepot method(NMxB).The catalysts were then characterized by XRD,XPS,NH3TPD,H_(2)TPR,HRTEM,and N_(2)adsorptiondesorption *** performance of the NiMo/Al_(2)O_(3) catalysts was investigated by hydrocracking lowtemperature coal *** the MoO3 content was 15 wt%,the interaction between Ni species and Al_(2)O_(3) on the NM15B catalyst was stronger than that on the NM15A catalyst,resulting in the poor performance of the *** the MoO^(3) content was 20 wt%,MoO_(3) agglomerated on the surface of the NM20A catalyst,leading to decreased number of active sites and specific surface area and reduced catalytic *** increase in the number of MoS_(2) stack layers strengthened the interaction between Ni and Mo species of the NM20B catalyst and consequently improved its catalytic *** the MoO_(3) content reached 25 wt%,the active metals agglomerated on the surface of the NiMo catalysts,thereby directly decreasing the number of active *** conclusion,the twostep method is suitable for preparing catalysts with large pore diameter and low MoO_(3) content loading,and the onepot method is more appropriate for preparing catalysts with large specific surface area and high MoO_(3) ***,the NMxA catalysts had larger average pore diameter than the NMxB catalysts and exhibited improved desulfurization performance.

关键词： Preparation methods Hydrocracking performance The NiMo catalysts MoO_(3)content

Models for the Formation and Dispersion of Potassium-filled Bubbles in Doped Tungsten Wire

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Rare Metals 1990年第2期10卷 117-123页

作者： Liu, Xinyu zuo, Tieyong Central South Univ of Technology China

The evolution of potassium-filled pores during the production and annealing of tungsten wire was observed by SEM and TEM, and the basic parameters of potassium-filled bubble rows were measured statistically. Based on disturbance theory and diffusion theory, analyses of shape unstability of tube-shaped second phases or pores in the metallic matrix are suitable for potassium-filled tubes in doped tungsten. Breakup models of long and thin potassium-filled tubes and ring shaped potassium-filled bubbles are given. The relationship between basic parameters of potassium-filled bubble rows and the size of potassium-filled tubes and the condition under which a potassium-filled tube can break up during annealing are also derived.

关键词： Heat Treatment Annealing Microscopic Examination Scanning Electron Microscopy

Flow-Induced Instabilities in Pump-Turbines in China

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Engineering 2017年第4期3卷 504-511页

作者： Zhigang zuo Shuhong Liu State Key Laboratory of Hydro Science and Engineering Department of Thermal Engineering Tsinghua University Beijing 100084 China

The stability of pump-turbines is of great importance to the operation of pumped storage power （PSP） stations. Both hydraulic instabilities and operational instabilities have been reported in PSP stations in China. In order to provide a reference to the engineers and scientists working on pump-turbines, this paper summarizes the hydraulic instabilities and performance characteristics that promote the operational instabilities encountered in pump-turbine operations in China. Definitions, analytical methods, numerical and experimental studies, and main results are clarified. Precautions and countermeasures are also provided based on a literature review. The gaps between present studies and the need for engineering practice are pointed out.

关键词： Pump-turbines Flow-induced instability Pressure fluctuations S-shaped characteristics Positive slopes

A hybrid deep neural network based on multi-time window convolutional bidirectional LSTM for civil aircraft APU hazard identification

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Chinese Journal of Aeronautics 2022年第4期35卷 344-361页

作者： Di ZHOU Xiao ZHUANG Hongfu zuo Civil A viation Key Laboratory of Aircraft Health Monitoring and Intelligent Maintenance College of Civil AviationNanjing University of Aeronautics and AstronauticsNanjing 210016China Department of Mechanical and Industrial Engineering University of TorontoToronto M5S 3G8Canada College of Science Nanjing University of Aeronautics and AstronauticsNanjing 210016China

Safety is one of the important topics in the field of civil aviation. Auxiliary Power Unit(APU) is one of important components in aircraft, which provides electrical power and compressed air for aircraft. The hazards in APU are prone to cause economic losses and even casualties. So,actively identifying the hazards in APU before an accident occurs is necessary. In this paper, a Hybrid Deep Neural Network(HDNN) based on multi-time window convolutional neural network-Bidirectional Long Short-Term Memory(CNN-Bi LSTM) neural network is proposed for active hazard identification of APU in civil aircraft. In order to identify the risks caused by different types of failures, the proposed HDNN simultaneously integrates three CNN-Bi LSTM basic models with different time window sizes in parallel by using a fully connected neural network. The CNN-Bi LSTM basic model can automatically extract features representing the system state from the input data and learn the time information of irregular trends in the time series data. Nine benchmark models are compared with the proposed HDNN. The comparison results show that the proposed HDNN has the highest identification accuracy. The HDNN has the most stable identification performance for data with imbalanced samples.

关键词： Civil aviation Convolutional neural networks Deep neural networks Hazard identification Long short-term memory

Traditional Chinese medicine for primary liver cancer

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World Journal of Gastroenterology 1998年第4期4卷 88-92页

作者： LI zuoQing Guangxi Cancer Research Institute Nanning 530027 Guangxi Province China Guangxi Tumor Research Institute Guangxi Medical University China

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ＴｒａｄｉｔｉｏｎａｌＣｈｉｎｅｓｅｍｅｄｉｃｉｎｅｆｏｒｐｒｉｍａｒｙｌｉｖｅｒｃａｎｃｅｒＬＩＺｕｏＱｉｎｇＳｕｂｊｅｃｔｈｅａｄｉｎｇｓＬｉｖｅｒｃａｎｃｅｒ，ｐｒｉｍａｒｙ；ＴＣＭ；ｃｏｍｐｌｉｃａｔｉｏｎ；ｐａｉｎ；ａｓｃｉｔｅｓ；ｆｅｖ...

关键词： Liver cancer, primary TCM complication pain ascites fever

Asphaltenes: Separations, structural analysis and applications

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Journal of Energy Chemistry 2019年第7期28卷 186-207页

作者： Pingping zuo Shijie Qu Wenzhong Shen State Key Laboratory of Coal Conversion Institute of Coal Chemistry Chinese Academy of Sciences

Asphaltenes, complex aromatic compounds from various carbonaceous sources, could be obtained by solvent dissolution, filtration and adsorption. It was difficult to clarify the molecular structures and chemical properties of asphaltene due to its structural similarity, composition complexity and source dependences. Many techniques, like Mass spectrometry, Chromatography, Nuclear magnetic resonance spectroscopy, Infrared spectroscopy, Roman spectroscopy, Fluorescence spectroscopy, X-ray diffraction analysis and Small-angle scattering techniques and so on, have revealed some valuable descriptions of asphaltenes chemical compositions and fundamental structures. Moreover, advanced Mass spectrometry,Atomic force microscopy and Scanning tunneling microscopy could provide more clear and essential molecular compounds and structures in asphaltenes. In addition, several asphaltenes models have succeeded to illustrate aggregation properties asphaltene. In this work, the progress on asphaltene separation, characterization and application was summarized, and the similarities and differences between coal-derived asphaltenes and petroleum asphaltenes were compared. Furthermore, the reactivity of asphaltenes has been discussed in the aspect of hydroprocessing, pyrolysis and gasification. Asphaltene was excellent carbon precursor for functional carbon material due to its high aromaticity and carbon yield;several porous carbon nanosheets from asphaltenes that would be prospective electrode materials after being graphitized were shown. Pitch-based carbon fiber derived from coal-derived asphaltenes displayed a tensile strength of 1.0 GPa and elastic modulus of 350 MPa, respectively. These powerful advances will provide asphaltenes promising developments.

关键词： Asphaltenes Separations Structures Aggregation Applications

Numerical investigation of granular mixing in an intensive mixer:Effect of process and structural parameters on mixing performance and power consumption

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Chinese Journal of Chemical Engineering 2021年第4期34卷 241-252页

作者： Zhijian zuo Shuguang Gong Guilan Xie School of Mechanical Engineering Xiangtan UniversityXiangtan 411105China

Discrete element method(DEM)simulations of particle mixing process in an intensive mixer were conducted to study the influence of structural and process parameters on the mixing performance and power *** DEM model was verified by comparing the impeller torque obtained from simulation with that from *** and vessel torque,coordination number(CN)and mixing index(Relative standard deviation)were adopted to qualify the particle dynamics and mixing performance with different parameters.A method based on cubic polynomial fitting was proposed to determine the critical mixing time and critical specific input work during the mixing *** is found that the mixing performance and energy efficiency increases with the decrease of impeller *** mixing performance is improved slightly with the increase of blade number and the impeller with 3 blades has the highest energy efficiency due to its low input *** indicate that the energy efficiency and the mixing performance increase with the decrease of filling level when the height of granular bed is higher than that of blade.

关键词： Intensive mixer Particle mixing DEM Mixing performance Power consumption

Measuring accessibility of bus system based on multi-source traffic data

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Geo-Spatial Information Science 2020年第3期23卷 248-257,I0005页

作者： Yufan zuo Zhiyuan Liu Xiao Fu School of Transportation Southeast UniversityNanjingChina Jiangsu Key Laboratory of Urban ITS Jiangsu Province Collaborative Innovation Center of Modern Urban Traffic TechnologiesSoutheast UniversityNanjingChina

Accessibility is a representative indicator for evaluating the supply of bus *** studies have evaluated the accessibility from different *** the interaction among land use,bus timetable arrangement and individual factors,a more holistic accessibility measurement is proposed to combine static and dynamic characteristics from multisource traffic *** rationale of the proposed model is verified by a case study of bus system in Shenzhen,China,which is carried out to find the spatial and temporal discrepancy of service of bus *** is found that the adjustment of bus schedule to time-varying travel demand can affect accessibility of bus system and that Land-use development,average bus speed and bus facilities all have positive effects on accessibility of bus *** findings provide sig-nificant reference for transport planning and *** proposed model is not limited to accessibility measuring of bus system,but also applicable to other travel modes.

关键词： Accessibility bus system multi-source traffic data spatial-temporal distribution

A Novel Prescribed-Performance Path-Following Problem for Non-Holonomic Vehicles

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IEEE/CAA Journal of Automatica Sinica 2024年第6期11卷 1476-1484页

作者： Zirui Chen Jingchuan Tang Zongyu zuo Seventh Research Division Beihang University(BUAA)Beijing 100191China IEEE

The issue of achieving prescribed-performance path following in robotics is addressed in this paper,where the aim is to ensure that a desired path within a specified region is accu-rately converged to by the controlled *** this context,a novel form of the prescribed performance guiding vector field is introduced,accompanied by a prescribed-time sliding mode con-trol ***,the interdependence among the pre-scribed parameters is *** validate the effectiveness of the proposed method,numerical simulations are presented to demonstrate the efficacy of the approach.

关键词： Guiding vector field non-holonomic vehicle path following prescribed performance sliding mode control