检索结果-南通市图书馆

Phase equilibrium data prediction and process optimizationin butadiene extraction process

Chinese Journal of Chemical engineering 2024年第7期71卷 1-12页

作者： Baowei Niu Yanjie Yi Yuwen Wei Fuzhen Zhang Lili Wang Li Xia Xiaoyan Sun Shuguang Xiang Institute of Process System engineering College of Chemical EngineeringQingdao University of Science and TechnologyQingdao 266042China

In response to the lack of reliable physical parameters in the process simulation of the butadiene extraction,a large amount of phase equilibrium data were collected in the context of the actual process of butadiene production by *** accuracy of five prediction methods,UNIFAC(UNIQUAC Functional-group Activity Coefficients),UNIFAC-LL,UNIFAC-LBY,UNIFAC-DMD and COSMO-RS,applied to the butadiene extraction process was verified using partial phase equilibrium *** results showed that the UNIFAC-DMD method had the highest accuracy in predicting phase equilibrium data for the missing ***-RS-predicted multiple systems showed good accuracy,and a large number of missing phase equilibrium data were estimated using the UNIFAC-DMD method and COSMO-RS *** predicted phase equilibrium data were checked for *** NRTL-RK(non-Random Two Liquid-Redlich-Kwong Equation of State)and UNIQUAC thermodynamic models were used to correlate the phase equilibrium *** device simulations were used to verify the accuracy of the thermodynamic model applied to the butadiene extraction *** simulation results showed that the average deviations of the simulated results using the correlated thermodynamic model from the actual values were less than 2%compared to that using the commercial simulation software,Aspen Plus and its *** average deviation was much smaller than that of the simulations using the Aspen Plus database(>10%),indicating that the obtained phase equilibrium data are highly accurate and *** best phase equilibrium data and thermodynamic model parameters for butadiene extraction are *** improves the accuracy and reliability of the design,optimization and control of the process,and provides a basis and guarantee for developing a more environmentally friendly and economical butadiene extraction process.

关键词： Butadiene extraction Phase equilibrium data Prediction methods Thermodynamic modeling Process simulation

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Deep Reinforcement Learning-Based Task Offloading and Service Migrating Policies in Service Caching-Assisted Mobile Edge Computing

引用

China Communications 2024年第4期21卷 88-103页

作者： Ke Hongchang Wang Hui Sun Hongbin Halvin Yang School of Computer technology and engineering Changchun Institute of TechnologyChangchun 130012China college of Computer Science and engineering Changchun University of TechnologyChangchun 130012China Department of Electronic and Electrical engineering University College LondonLondonUK

Emerging mobile edge computing(MEC)is considered a feasible solution for offloading the computation-intensive request tasks generated from mobile wireless equipment(MWE)with limited computational resources and *** to the homogeneity of request tasks from one MWE during a longterm time period,it is vital to predeploy the particular service cachings required by the request tasks at the MEC *** this paper,we model a service caching-assisted MEC framework that takes into account the constraint on the number of service cachings hosted by each edge server and the migration of request tasks from the current edge server to another edge server with service caching required by ***,we propose a multiagent deep reinforcement learning-based computation offloading and task migrating decision-making scheme(MBOMS)to minimize the long-term average weighted *** proposed MBOMS can learn the near-optimal offloading and migrating decision-making policy by centralized training and decentralized *** and comprehensive simulation results reveal that our proposed MBOMS can converge well after training and outperforms the other five baseline algorithms.

关键词： deep reinforcement learning mobile edge computing service caching service migrating

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Consumer-branch Connectivity Identification of Low Voltage Distribution Networks Based on Data-driven Approach

引用

Protection and Control of Modern Power Systems 2024年第4期9卷 69-82页

作者： Yongjun Zhang Yingqi Yi Wenyang Deng Siliang Liu Lai Zhou Kaidong Lin Yongzhi Cai the School of Electric Power engineering and Guangdong Key Laboratory of Clean Energy technology South China Uni-versity of TechnologyGuangzhou 510641China the School of Elec-tric Power engineering South China University of TechnologyGuangzhou 510641China the Guangzhou Panyu vocational and technical college Guangzhou 511483China the metrology Center Guangdong Power Company Grid Qingyuan 511500China

Accurate topological information is crucial in supporting the coordinated operational requirements of source-load-storage in low-voltage distribution *** coverage of smart meters provides a database for low-voltage topology identification(LVTI).However,because of electricity theft,power line commu-nication crosstalk,and interruption of communication,the measurement data may be *** can seriously affect the performance of LVTI ***,this paper defines hidden errors and proposes an LVTI method based on layer-by-layer stepwise *** the first step,a multi-linear regression model is developed for consumer-branch connectivity identification based on the energy conservation *** the second step,a significance factor based on the t-test is proposed to modify the identification results by considering the hidden *** the third step,the regression model and significance threshold parameters are iteratively updated layer by layer to improve the recall rate of the final identification ***,simulations of a test system with 63 users are carried out,and the practical application results show that the proposed method can guarantee over 90%precision under the influence of hidden errors.

关键词： Data driven hidden error linear re-gression low voltage distribution network topology identification

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Bifunctional core–shell co-catalyst for boosting photocatalytic CO_(2) reduction to CH_(4)

引用

Nano Research 2024年第3期17卷 1259-1266页

作者： Fangxu Dai Mingming Zhang Jishu Han Zhenjiang Li Shouhua Feng Jun Xing Lei Wang Key Laboratory of Eco-chemical engineering Ministry of EducationCollege of Chemistry and Molecular EngineeringQingdao University of Science and TechnologyQingdao 266042China college of Materials Science and engineering Qingdao University of Science and TechnologyQingdao 266042China college of Environment and Safety engineering Qingdao University of Science and TechnologyShandong Engineering Research Center for Marine Environment Corrosion and Safety ProtectionQingdao 266042China

Solar-light-driven CO_(2) reduction CO to CH_(4) and C2H6 is a complex process involving multiple elementary reactions and energy ***,achieving high CH_(4) activity and selectivity remains a significant ***,we integrate bifunctional Cu2O and Cu-MOF(MOF=metal-organic framework)core–shell co-catalysts(Cu2O@Cu-MOF)with semiconductor TiO_(2).Experiments and theoretical calculations demonstrate that Cu2O(Cu+facilitates charge separation)and Cu-MOF(Cu2+improves the CO_(2) adsorption and activation)in the core–shell structure have a synergistic effect on photocatalytic CO_(2) reduction,reducing the formation barrier of the key intermediate*COOH and**** photocatalyst exhibits high CH_(4) yield(366.0μmol·g^(-1)·h^(-1)),efficient electron transfer(3283μmol·g^(-1)·h^(-1))and hydrocarbon selectivity(95.5%),which represents the highest activity of Cu-MOF-based catalysts in photocatalytic CO_(2) reduction *** work provides a strategy for designing efficient photocatalysts from the perspective of precise regulation of components.

关键词： bifunctional co-catalyst core–shell photocatalytic CO_(2)reduction

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Cooperative control for heterogeneous multi-agent systems: progress, applications, and challenges

引用

Science China(Information Sciences) 2024年第5期67卷 318-320页

作者： Bing YAN Peng SHI Jonathon CHAMBERS School of Electrical and Mechanical engineering Faculty of Science Engineering and TechnologyThe University of Adelaide School of engineering College of Science and Engineering University of Leicester

Cooperative control for heterogeneous multi-agent systems(MASs) is a critical and rapidly evolving field in modern automation and robotics. Characterized by the integration of agents with diverse capabilities and func... 详细信息

关键词： Multi agent systems

来源：

同方期刊数据库评论

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Pyrolysis technologies for biochar production in waste management:a review

引用

Clean Energy 2024年第4期8卷 61-78页

作者： Kavan Kumar V NLPanwar Department of Renewable Energy engineering College of Technology and EngineeringMPUATUdaipurRajasthan 313001India

Pyrolysis is a thermal conversion process in the absence of air to derive energy components from the ***-energy technologies will play a major role in addressing future challenges related to environmental safety and energy *** of the many easily available renewable energy sources is biomass-an organic material that is thought to be *** technology is a thermochemical process that can be used to produce useful products from biomass,such as biochar,bio-oil and combustible pyrolysis *** structure and relative product yield are impacted by the pyrolysis method *** article evaluates different approaches for biomass ***,slow and advanced pyrolysis methods using various pyrolyser reactors have been studied in the literature and are provided to increase the variety and use of these methods in upcoming studies and re*** pyrolysis can lead to increased ecological well-being,as it increases the amount of biochar produced using auger and rotary-kiln *** pyrolysis,mainly in fluidized-bed reactors with bubbling and rotating circulation,can be used to obtain *** pyrolysis methods offer a good probability of yielding great prosperity for specific *** selection of a pyrolysis process is based on the required output in terms of solid,liquid and gaseous fuels,and the parameter plays a crucial role in the pyrolysis performance.

关键词： biomass thermochemical process slow pyrolysis fast pyrolysis and advanced pyrolysis

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Macro-micro behaviors and failure mechanism of frozen weakly cemented mudstone

引用

Journal of Rock Mechanics and Geotechnical engineering 2024年第4期16卷 1337-1347页

作者： Xianzhou Lyu Jijie Du Hao Fu Dawei Lyu Weiming Wang college of Earth Science and engineering Shandong University of Science and TechnologyQingdao266590China college of Civil engineering and Architecture Shandong University of Science and TechnologyQingdao266590China

Understanding the mechanical properties and multiscale failure mechanism of frozen soft rock is an important prerequisite for the construction safety of tunnels,artificially frozen ground and other infrastructure in cold *** this study,the triaxial compression test are performed on mudstone in the weakly cemented soft rock strata in the mining area of western China,and the mechanical characteristics and failure mechanism of weakly cemented mudstone are systematically investigated under the combined action of freezing and ***,the quantitative relationship between the microstructural parameters and the macroscopic strength and deformation parameters is established based on fractal ***,the failure mechanism of frozen weakly cemented mudstone is revealed on both micro- and *** results show that temperature and confining pressure significantly affects the elastic modulus and peak strength of weakly cemented *** decreasing temperature,the compressive strength increases,while the corresponding peak strain decreases *** the deformation curve,the plastic deformation stage is shortened,and the brittle fracture feature at the post-peak stage is more prominent,and the elastic modulus correspondingly increases with decreasing *** low-temperature conditions,most of the weakly cemented mudstone undergoes microscopic shear failure along the main fracture *** micro-fracture morphology characteristics of weakly cemented mudstone under different temperatures are quantified via the fractal dimension,and an approximately exponential relationship can be obtained among the fractal dimension and the temperature,compressive strength and elastic modulus.

关键词： Weakly cemented mudstone Artificial freezing Mechanical properties Linkage destruction mechanism Fractal dimension

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Hydrochemical insights on the signatures and genesis of water resources in a high-altitude city on the Qinghai-Xizang Plateau, South-west China

引用

Frontiers of Environmental Science & engineering 2024年第7期18卷 123-140页

作者： Jiutan Liu Kexin Lou Zongjun Gao Menghan Tan college of Earth Science and engineering Shandong University of Science and TechnologyQingdao 266590China

Water resources have crucial implications for the steady development of the urban social *** study investigated the hydrochemical signatures and genesis of water resources in the urban area of Lhasa City(UALC).To this end,several analyses,such as ion ratio analysis and correlation analysis,were performed by comprehensively applying mathematical statistics and integrated hydrochemical *** results show relatively low concentrations of major ions in the groundwater and surface water(GSW)of the *** primary anions and cations are HCO3-and Ca2+,reflecting the HCOg-Ca water ***,groundwater exhibits higher concentrations of key chemical components compared to surface *** are weakly alkaline,with pH values of 7.78 and 7.61,respectively,and they have low salinity with average concentrations of total dissolved solids being 190.74 and 112.17 mg/L,*** inputs have minimal influence on the hydrochemical features of GSw,whereas rock weathering is the dominant controlling ***,cation *** a significant *** influencing their hydrochemical *** to the isotope analysis(H and 180),the primary source of recharge for GSW is atmospheric precipitation,with some input from melted ice and ***,GSW samples from the UALC show relatively similar 2H and 18O isotopic compositions,indicating the existence of a discernible hydraulic connection linking the two water *** research findings can serve as a valuable scientific reference and foundation for the sustainable development,effective utilization,and proper safeguarding of regional water resources in high-altitude areas.

关键词： Groundwater and surface water Hydrochemical features Genesis mechanism Water quality Urban area of Lhasa City

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Optical detection method of discharge mode transition of inductively coupled plasma in an atmosphere-breathing electric propulsion system

引用

Chinese Journal of Aeronautics 2024年第10期37卷 172-183页

作者： Yuxuan ZHONG Yu ZHANG Jianjun WU Peng ZHENG college of Aerospace Science and engineering National University of Defense TechnologyChangsha 410073China

Plasma discharge stability is an important problem in atmosphere-breathing electric propulsion system when maintaining long-term missions at ultra-low earth *** paper designed an inductively coupled plasma source to imitate the ionization *** effect of inflow rate and Radio Frequency(RF)power on the plasma discharge mode transition is experimentally studied.A discharge mode detection method is proposed,which determines the discharge mode by identifying the morphology of the plasma *** using the method,the discharge mode transition is quantified and a control model based on the parameter sensitivity is *** verify the method,the spectra are measured and the electron temperature spatial distribution is *** the method has been proven *** results show that the inductively coupled discharge contains capacitive components affected by the mass flow rate and the radio frequency *** plasma characteristics can be maintained stably by controlling the radio frequency power when the mass flow rate randomly changes in a certain *** is demonstrated that the application of detection method effectively identifies the discharge mode,which is a promising active control method for the plasma discharge mode.

关键词： Atmosphere-breathing electric propulsion Inductively coupled plasma Discharge mode transition Optical diagnosis Ultra-low earth orbit

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Six million Q factor micro fused silica shell resonator with teeth-like tines released by femtosecond laser-assisted chemical etching

引用

Science China(Technological Sciences) 2024年第6期67卷 1923-1932页

作者： ZHAO Tao SHI Yan LU Kun XI Xiang WU XueZhong XIAO DingBang college of Intelligence Science and engineering National University of Defense TechnologyChangsha410073China

The quality factor(Q factor)is a crucial performance parameter for *** this paper,a novel release method for highquality micro fused silica shell resonators with teeth-like tines with good surface morphology is *** method is based on femtosecond laser-assisted chemical ***,the optimal energy range of femtosecond laser modification is obtained through mechanism ***,the optimal parameters for a straight line and arc pattern are determined by optimizing the average output power,processing speed,and processing *** results demonstrate why edge breakage in rounded corners is easy under different ***,according to these conclusions,the processing is performed on a micro fused silica shell resonator with a Q factor exceeding 6 *** addition,subsurface damage is rare throughout the fabrication process,and the surface roughness of the released cross section reaches the nanometer *** improved Q factor helps suppress mechanical thermal noise and reduce zero bias and zero bias drift,constituting the primary method for enhancing the performance of the resonant gyroscope.

关键词： micro hemispherical resonator fused silica laser-assisted chemical etching quality factor

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

欢迎您,

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案：

请选择收藏分类：

通借通还

欢迎您,

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：