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LDPE稀相输送系统中弯头的磨损与选型对产品质量的影响

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塑料工业 2024年第7期52卷 112-118页

作者：高翔苟荣恒杜振国张箭飞闫帅张金龙易奇陈鹏王丹国家能源集团新疆化工有限公司新疆乌鲁木齐831400

低密度聚乙烯(LDPE)装置气力输送系统常采用稀相输送,物料在输送管路中以“悬浮式”前进,该输送方法具有易于维护、适用范围广、经济性高、流速快等特点。但正是因为输送速度快,物料在较长的输送管路上摩擦,容易导致物料损失和输送设备... 详细信息

低密度聚乙烯(LDPE)装置气力输送系统常采用稀相输送,物料在输送管路中以“悬浮式”前进,该输送方法具有易于维护、适用范围广、经济性高、流速快等特点。但正是因为输送速度快,物料在较长的输送管路上摩擦,容易导致物料损失和输送设备的磨损。一方面,输送时高速流动的粒子与管壁、弯头相互摩擦、碰撞,产生细粉和丝团料。另一方面高速运动的粒子持续撞击和摩擦输送管道,导致输送管道磨损和寿命变短。因此,本文通过工程实践采用对比分析的方法从聚乙烯颗粒稀相输送的磨损机理和输送弯头的选型两个方面展开探讨,总结和分析了输送弯头选型对LDPE颗粒产品质量的影响,为同类装置稀相输送系统弯头选型提供一定的理论支持。

关键词：低密度聚乙烯稀相输送弯头产品质量

Adaptive learning-based optimal tracking control system design and analysis of a disturbed nonlinear hypersonic vehicle model

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Science China(Technological Sciences) 2024年第6期67卷 1893-1906页

作者： AN Kai WANG zhenguo HUANG Wei Hypersonic Technology Laboratory National University of Defense TechnologyChangsha410073China

We propose an adaptive learning-based optimal control scheme for height-velocity control models considering model uncertainties and external disturbances of hypersonic winged-cone *** longitudinal nonlinear model is first established and transformed into the control-oriented error equations,and the control scheme is organized by a steady-compensation *** overcome and eliminate the impact of model uncertainties and external disturbances,an adaptive radial basis function neural network(RBFNN)is designed by a q-gradient *** the height-velocity error system with estimated uncertainties into account,the adaptive learning-based optimal tracking control(ALOTC)scheme is proposed by combining the critic-only adaptive dynamic programming(ADP)framework and parameter optimization of system settling ***,a novel weight update law is proposed to satisfy the online iteration requirements,and the algorithm convergence and closedloop stability are discussed by the Lyapunov ***,four simulation cases are provided to prove the effectiveness,accuracy,and robustness of the proposed scheme for the hypersonic longitudinal control system.

关键词： optimal tracking control adaptive dynamic programming RBFNN hypersonic vehicle

Optimal Design of the Modular Joint Drive Train for Enhancing Cobot Load Capacity and Dynamic Performance

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Chinese Journal of Mechanical Engineering 2024年第3期37卷 26-40页

作者： Peng Li zhenguo Nie Zihao Li Xinjun Liu Department of Mechanical Engineering Tsinghua UniversityBeijing 100084China State Key Laboratory of Tribology in Advanced Equipment Tsinghua UniversityBeijing 100084China Beijing Key Lab of Precision/Ultra-precision Manufacturing Equipments and Control Tsinghua UniversityBeijing 100084China

Automation advancements prompts the extensive integration of collaborative robot(cobot)across a range of *** to the commonly used design approach of increasing the payload-to-weight ratio of cobot to enhance load capacity,equal attention should be paid to the dynamic response characteristics of cobot during the design process to make the cobot more *** this paper,a new method for designing the drive train parameters of cobot is ***,based on the analysis of factors influencing the load capacity and dynamic response characteristics,design criteria for both aspects are established for cobot with all optimization design criteria normalized within the design ***,with the cobot in the horizontal pose,the motor design scheme is discretized and it takes the joint motor diameter and gearbox speed ratio as optimization design ***,all the discrete values of the optimization objectives are obtained through the enumeration method and the Pareto front is used to select the optimal solution through multi-objective *** on the cobot design method proposed in this paper,a six-axis cobot is designed and compared with the commercial *** result shows that the load capacity of the designed cobot in this paper reaches 8.4 kg,surpassing the 5 kg load capacity commercial cobot which is used as a *** minimum resonance frequency of the joints is 42.70 Hz.

关键词： Multi-objective optimization Modular joint drive train design Load capacity Dynamic response performance

Equivalent Impedance Parameter Calculation of Three-phase Symmetrical Loads for Harmonic Source Location

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Journal of Modern Power Systems and Clean Energy 2024年第1期12卷 251-260页

作者： Yi Zhang Bijie Liu Caihua Lin zhenguo Shao Yuncong Xu the Department of Electrical Engineering and Automation Fuzhou UniversityFuzhouChina State Grid Fujian Electric Power Research Institute FuzhouChina

The equivalent impedance parameters of loads have been widely used to identify and locate the harmonic ***,the existing calculation methods suffer from outliers caused by the zero-crossing of the *** outliers can result in inaccuracy and unreliability of harmonic source *** address this issue,this paper proposes an innovative method of equivalent impedance parameter calculation of three-phase symmetrical loads that avoid *** correctness and effectiveness of the proposed method are verified by simulations on Simulink using actual monitoring *** results show that the proposed method is not only simple and easy to implement but also highly accurate.

关键词： abc-αβtransformation equivalent impedance parameters of load harmonic source location nonlinear load power quality

A Physics‑Based Seismic Risk Assessment of the Qujiang Fault:From Dynamic Rupture to Disaster Estimation

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International Journal of Disaster Risk Science 2024年第1期15卷 165-177页

作者： Yilong Li Zijia Wang zhenguo Zhang Yuhao Gu Houyun Yu School of National Safety and Emergency Management Beijing Normal UniversityZhuhai 519087China Department of Earth and Space Sciences Southern University of Science and TechnologyShenzhen 518055China Guangdong Provincial Key Laboratory of Geophysical High-Resolution Imaging Technology Southern University of Science and TechnologyShenzhen 518055China

This study achieved the construction of earthquake disaster scenarios based on physics-based methods-from fault dynamic rupture to seismic wave propagation-and then population and economic loss *** physics-based dynamic rupture and strong ground motion simulations can fully consider the three-dimensional complexity of physical parameters such as fault geometry,stress field,rock properties,and *** analysis of multiple seismic disaster scenarios along the Qujiang Fault in western Yunnan Province in southwestern China based on different nucleation locations was *** results indicate that the northwestern segment of the Qujiang Fault is expected to experience significantly higher levels of damage compared to the southeastern ***,there are significant variations in human losses,even though the economic losses are similar across different *** Bai Autonomous Prefecture,Chuxiong Yi Autonomous Prefecture,Yuxi City,Honghe Hani and Yi Autonomous Prefecture,and Wenshan Zhuang and Miao Autonomous Prefecture were identified as at medium to high seismic risks,with Yuxi and Honghe being particularly *** targeted earthquake prevention measures in Yuxi and Honghe will significantly mitigate the potential risks posed by the Qujiang ***,although the fault is within Yuxi,Honghe is likely to suffer the most severe *** findings emphasize the importance of considering rupture directivity and its influence on ground motion distribution when assessing seismic risk.

关键词： Earthquake disaster loss estimation Physics-based earthquake scenario simulation Qujiang Fault Rupture directivity Seismic risk assessment

Multi-scale analyses of phase transformation mechanisms and hardness in linear friction welded Ti17(a+β)/Ti17(β)dissimilar titanium alloy joint

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Chinese Journal of Aeronautics 2024年第1期37卷 312-324页

作者： zhenguo GUO Tiejun MA Xiawei YANG Ju LI Wenya LI Achilles VAIRIS State Key Laboratory of Solidification Processing Shaanxi Key Laboratory of Friction Welding TechnologiesNorthwestern Polytechnical UniversityXi’an 710072China Aeronautical Key Laboratory for Welding and Joining Technologies AVIC Manufacturing Technology InstituteBeijing 100024China Mechanical Engineering Department University of West AtticaAthens 12241Greece

The Ti17(a+β)-Ti17(β)dual alloy-dual property blisk produced using Linear Friction Welding(LFW)is considered as high-performance component in advanced ***,up to now,microstructure evolution and relationship between microstructure and micro mechanical properties of LFWed Ti17(a+β)/Ti17(β)dissimilar joint have not been thoroughly *** this work,complex analyses of the phase transformation mechanisms of the joint are conducted,and phase transformations in individual zones are correlated to their microhardness and *** reveal that a dissolution occurs under high temperatures encountered during LFW,which reduces microhardness of the joint to that of Ti17(a+β)and Ti17(β).In ThermoMechanically Affected Zone of Ti17(a+β)(TMAZ-(a+β))side joint,a large number of nanocrystalline a phases form with different *** microstructure strengthens significantly by fine grains which balances partial softening effect of a dissolution,and increases nanohardness of a phase and microhardness of TMAZ-(a+β).Superlattice metastableβphase precipitates from metastableβin Weld Zone(WZ)during quick cooling following welding,because of short-range diffusion migration of solute atoms,especiallyβstabilizing elements Mo and *** precipitation of the superlattice metastableβphase results in precipitation strengthening,which in turn increases nanohardness of metastableβand microhardness in WZ.

关键词： Linear friction welding Ti17 titanium alloy Phase transformation Microhardness Nanohardness

Co_(3)O_(4)as an efficient passive NO_(x) adsorber for emission control during cold-start of diesel engines

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Chinese Journal of Chemical Engineering 2024年第2期66卷 1-7页

作者： Jinhuang Cai Shijie Hao Yun Zhang Xiaomin Wu zhenguo Li Huawang Zhao Department of Environmental Science&Engineering College of Chemical EngineeringHuaqiao UniversityXiamen 361021China Wuxi Weifu Environmental Catalysts Co. LtdWuxi 214000China National Engineering Laboratory for Mobile Source Emission Control Technology China Automotive Technology&Research Center Co.Ltd.Tianjin 300300China

The Co_(3)O_(4)nanoparticles,dominated by a catalytically active(110)lattice plane,were synthesized as a low-temperature NO_(x) adsorbent to control the cold start emissions from *** nanoparticles boast a substantial quantity of active chemisorbed oxygen and lattice oxygen,which exhibited a NO_(x) uptake capacity commensurate with Pd/SSZ-13 at 100℃.The primary NO_(x) release temperature falls within a temperature range of 200-350℃,making it perfectly suitable for diesel *** characterization results demonstrate that chemisorbed oxygen facilitate nitro/nitrites intermediates formation,contributing to the NO_(x) storage at 100℃,while the nitrites begin to decompose within the 150-200℃***,lattice oxygen likely becomes involved in the activation of nitrites into more stable nitrate within this particular temperature *** concurrent processes of nitrites decomposition and its conversion to nitrates results in a minimal NO_(x) release between the temperatures of 150-200℃.The nitrate formed via lattice oxygen mainly induces the NO_(x) to be released as NO_(2) within a temperature range of 200-350℃,which is advantageous in enhancing the NO_(x) activity of downstream NH_(3)-SCR catalysts,by boosting the fast SCR reaction *** to its low cost,considerable NO_(x) absorption capacity,and optimal release temperature,Co_(3)O_(4)demonstrates potential as an effective material for passive NO_(x) adsorber applications.

关键词： Emission control Cold-start Low-temperature adsorption Co_(3)O_(4) Nitrate formation

Online soft measurement for wastewater treatment system based on hybrid deep learning

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Frontiers of Environmental Science & Engineering 2024年第2期18卷 77-89页

作者： Wenjie Mai zhenguo Chen Xiaoyong Li Xiaohui Yi Yingzhong Zhao Xinzhong He Xiang Xu Mingzhi Huang SCNU Environmental Research Institute Guangdong Provincial Key Laboratory of Chemical Pollution and Environmental Safety&MOE Key Laboratory of Theoretical Chemistry of EnvironmentSchool of EnvironmentSouth China Normal UniversityGuangzhou 510006China Fujian Environmental Protection Design Institute Co.Ltd. Fuzhou 350000China Huashi(Fujian)Environment Technology Co.Ltd. Quanzhou362001China SCNU Qingyuan Institute of Science and Technology Innovation Co.Ltd. Qingyuan 511517China Econ Technology Co.Ltd. Yantai 265503China

The existing automated wastewater treatment control systems encounter challenges such as the utilization of specialized testing instruments, equipment repair complications, high operational costs, substantial operational errors, and low detection accuracy. An effective soft measure model offers a viable approach for real-time monitoring and the development of automated control in the wastewater treatment process. Consequently, a novel hybrid deep learning CNN-BNLSTM-Attention (CBNLSMA) model, which incorporates convolutional neural networks (CNN), bidirectional nested long and short-term memory neural networks (BNLSTM), attention mechanisms (AM), and Tree-structure Parzen Estimators (TPE), has been developed for monitoring effluent water quality during the wastewater treatment process. The CBNLSMA model is divided into four stages: the CNN module for feature extraction and data filtering to expedite operations;the BNLSTM module for temporal data’s temporal information extraction;the AM module for model weight reassignment;and the TPE optimization algorithm for the CBNLSMA model’s hyperparameter search optimization. In comparison with other models (TPE-CNN-BNLSTM, TPE-BNLSTM-AM, TPE-CNN-AM, PSO-CBNLSTMA), the CBNLSMA model reduced the RMSE for effluent COD prediction by 25.4%, decreased the MAPE by 32.9%, and enhanced the R2 by 14.9%. For the effluent SS prediction, the CBNLSMA model reduced the RMSE by 26.4%, the MAPE by 21.0%, and improved the R2 by 35.7% compared to other models. The simulation results demonstrate that the proposed CBNLSMA model holds significant potential for real-time effluent quality monitoring, indicating its high potential for automated control in wastewater treatment processes.

关键词： Prediction model Soft measurement CNN-BNLSTM-AM model TPE optimization algorithm

Efficient NO_x abatement by passive adsorption over a Pd-SAPO-34 catalyst prepared by solid-state ion exchange

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Chinese Chemical Letters 2024年第4期35卷 210-213页

作者： Linhui Liu Wuwan Xiong Mingli Fu Junliang Wu zhenguo Li Daiqi Ye Peirong Chen National Engineering Laboratory for VOCs Pollution Control Technology and Equipment Guangdong Provincial Key Laboratory of Atmospheric Environment and Pollution ControlSchool of Environment and EnergySouth China University of TechnologyGuangzhou 510006China National Engineering Laboratory for Mobile Source Emission Control Technology China Automotive Technology&Research Center Co.Ltd.Tianjin 300300China

Palladium-exchanged chabazite(Pd-CHA) zeolites as passive NO_x adsorbers(PNAs) enable efficient purification of nitrogen oxides(NO_x) in cold-start diesel exhausts. Their commercial application, however,is limited by the lack of facile preparation method. Here, high-performance CHA-type Pd-SAPO-34 zeolite was synthesized by a modified solid-state ion exchange(SSIE) method using PdO as Pd precursor,and demonstrated superior PNA performance as compared to Pd-SAPO-34 prepared by conventional wetchemistry strategies. Structural characterization using Raman spectroscopy and X-ray diffraction revealed that the SSIE method avoided water-induced damage to the zeolite framework during Pd loading. Mechanistic investigations on the SSIE process by in situ infrared spectroscopy and X-ray photoelectron spectroscopy disclosed that, while PdO precursor was mainly converted to Pd^(2+) cations coordinated to the zeolite framework by consuming the-OH groups of the zeolite, a portion of PdO could also undergo thermal decomposition to form highly dispersed Pd~0 clusters in the pore channels. This simplified and scalable SSIE method paves a new way for the cost-effective synthesis of defect-free high-performance Pd-SAPO-34 zeolites as PNA catalysts.

关键词： Pd-SAPO-34 Passive NO_x adsorber Pd loading Solid-state ion exchange Pd transformation