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Hybrid modeling for carbon monoxide gas-phase catalytic coupling to synthesize dimethyl oxalate process

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Chinese Journal of Chemical Engineering 2024年第6期70卷 234-250页

作者： Shida Gao Cuimei Bo Chao Jiang Quanling Zhang Genke yang Jian chu Ningbo Artificial Intelligence Institute Shanghai Jiao Tong UniversityNingbo 315012China Department of Automation Shanghai Jiao Tong UniversityShanghai 200240China Key Laboratory of Industrial Internet+Safety Production of Hazardous Chemical Ministry of Emergency ManagementNanjing Tech UniversityNanjing 211816China

Ethylene glycol(EG)plays a pivotal role as a primary raw material in the polyester industry,and the syngas-to-EG route has become a significant technical route in *** carbon monoxide(CO)gas-phase catalytic coupling to synthesize dimethyl oxalate(DMO)is a crucial process in the syngas-to-EG route,whereby the composition of the reactor outlet exerts influence on the ultimate quality of the EG product and the energy consumption during the subsequent separation ***,measuring product quality in real time or establishing accurate dynamic mechanism models is *** effectively model the DMO synthesis process,this study proposes a hybrid modeling strategy that integrates process mechanisms and data-driven *** CO gas-phase catalytic coupling mechanism model is developed based on intrinsic kinetics and material balance,while a long short-term memory(LSTM)neural network is employed to predict the macroscopic reaction rate by leveraging temporal relationships derived from archived *** proposed model is trained semi-supervised to accommodate limited-label data scenarios,leveraging historical *** integrating these predictions with the mechanism model,the hybrid modeling approach provides reliable and interpretable forecasts of mass *** investigations unequivocally validate the superiority of the proposed hybrid modeling approach over conventional data-driven models(DDMs)and other hybrid modeling techniques.

关键词： Carbon monoxide Dynamic modeling Hybrid model Reaction kinetics Semi-supervised learning

Genesis of the Jianbeigou Gold Deposit on the Southern Margin of the North China Craton: Insights from Fluid Inclusions, H-O-S Isotopes, and Pyrite in situ Trace Element Analyses

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Acta Geologica Sinica(English Edition) 2024年第4期98卷 969-991页

作者： LI Fengchun ZENG Qingdong ZHU Rixiang chu Shaoxiong XIE Wei YU bing WU Jinjian LI Xinghui Key Laboratory of Mineral Resources Institute of Geology and GeophysicsChinese Academy of SciencesBeijing 100029China Innovation Academy for Earth Science Chinese Academy of SciencesBeijing 100029China College of Earth and Planetary Sciences University of Chinese Academy of SciencesBeijing 100049China State Key Laboratory of Lithospheric Evolution Institute of Geology and GeophysicsChinese Academy of SciencesBeijing 100029China School of Earth Science and Engineering Hebei University of EngineeringHandanHebei 056038China

The Jianbeigou gold deposit is a typical lode gold deposit in the Qinling metallogenic belt, located on the southern margin of the North China Craton. Three stages of the hydrothermal process can be distinguished, including the quartz ± pyrite, quartz-polymetallic sulfide, and quartz-carbonate ± pyrite stages. From the early to late stages, the homogenization temperatures of primary fluid inclusions are 281–362°C, 227–331°C, and 149–261°C, respectively. The corresponding salinities estimated for these fluids are 3.9–9.9 wt%, 0.4–9.4 wt%, and 0.7–7.2 wt% Na Cl equiv. Combined with laser Raman spectroscopy data, the ore-forming fluid belongs to a H_(2)O-CO_(2)-Na Cl ± CH_4 system with medium–low temperature and salinity. The δ~(18)Ofluid and δD values for the quartz veins are-1.0‰ to 6.0‰ and-105‰ to-84‰, respectively, which indicates that the ore-forming fluid is of mixed source, mainly derived from magma, with a contribution from meteoric water. Pyrite has been identified into three generations based on mineral paragenetic sequencing, including Py1, Py2, and Py3. The pyrites have δ~(34)S sulfur isotopic compositions from three stages between 3.7‰ and 8.4‰, indicating that sulfur mainly originated from magma. Te, Bi, Sb, and Cu contents in pyrite were all high and showed a strong correlation with Au concentrations. Native gold and the Au-Ag-Bi telluride minerals were formed concurrently, and the As concentration was low and decoupled from the Au content. Therefore, Te, Bi, Sb and other low-melting point chalcophile elements play an important role for gold mineralization in arsenic-deficient ore-forming fluid. Combined with the geological setting, evolution of pyrite, and ore-fluids geochemistry, we propose that the Jianbeigou deposit can be classified as a magmatic–hydrothermal lode gold deposit. Gold mineralization on the southern margin of the North China Craton is related to Early Cretaceous magmatism and formed in an extensional setting.

关键词： ore genesis H-O-S isotopes fluid inclusions in-situ trace element Jianbeigou gold deposit

Asymmetric Zn-N4 atomic sites embedded hollow fibers as stable Zn anode for high-performance Zn-ion hybrid capacitor

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Journal of Energy Chemistry 2024年第10期97卷 460-469页

作者： Yukun Liu bing Li Jin Wang Caiyun Li Hongrui yang yang Song Sen Zhang Chao Deng Key Laboratory for Photonic and Electronic Bandgap Materials Ministry of Education College of Physics and Electronic Engineering Harbin Normal University College of Material Science and Chemical Engineering Harbin Engineering University

Zn based electrochemical energy storage systems（EES） have attracted tremendous interests owing to their low cost and high intrinsic ***,the uncontrolled growth of Zn dendrites and the side reactions of Zn metal anodes（ZMAs） severely restrict their *** address these issues,we design the asymmetric Zn-N4atomic sites embedded hollow fibers（AS-IHF） as the flexible host for stable *** introducing different nitrogen resources in the synthesis,two kinds of coordination,i,***-N（pyridinic） and Zn-N（pyrrolic）,are introduced in the Zn-N4atomic module *** asymmetric Zn-N4module with regulated micro-environment facilitates the superior zincophilic features and promotes the Zn ***,the highly porous structure of the hollow fiber effectively reduces local current density,homogenize Zn ion flux,and alleviate structure *** the advantages endow the high efficiency and good stability for Zn plating/*** theoretical and experimental results demonstrate the high reversibility,low nucleation overpotential,and dendritefree behavior of the AS-IHF@Zn anode,which afford the high stability in high-rate and long-term ***,the solid-state Zn-ion hybrid capacitor（ZIHC） based on AS-IHF@Zn anode shows the high flexibility,reliability,and superior long-term cycling capability in a wide-range of temperatures（-20-25℃）.Therefore,the present work not only gives a new strategy for modulating local environments of single atomic sites,but also propels the development of flexible power sources for diverse electronics.

关键词： Asymmetric coordination Dendrite free behavior Single atomic sites Zincophilic sites Zn-ion hybrid capacitor

Simulation of Dynamic Recrystallization in 7075 Aluminum Alloy Using Cellular Automaton

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Journal of Wuhan University of Technology(Materials Science) 2024年第2期39卷 425-435页

作者：赵晓东 SHI Dongxing 李亚杰 QIN Fengming chu Zhibing yang Xiaorong School of Materials Science and Engineering Taiyuan University of Science and TechnologyTaiyuan 030024China

The evolution of microstructure during hot deformation is key to achieving good mechanical properties in aluminum *** have developed a cellular automaton(CA) based model to simulate the microstructural evolution in 7075 aluminum alloy during hot *** compression tests were conducted to obtain material parameters for 7075 aluminum alloy,leading to the establishment of models for dislocation density,nucleation of recrystallized grains,and grain *** these aspects with grain topological deformation,our CA model effectively predicts flow stress,dynamic recrystallization(DRX) volume fraction,and average grain size under diverse deformation conditions.A systematic comparison was made between electron back scattered diffraction(EBSD) maps and CA model simulated under different deformation temperatures(573 to 723 K),strain rates(0.001 to 1 s^(-1)),and strain amounts(30% to 70%).These analyses indicate that large strain,high temperature,and low strain rate facilitate dynamic recrystallization and grain *** results from the CA model show good accuracy and predictive capability,with experimental error within 10%.

关键词： cellular automaton dynamic recrystallization 7075 aluminum alloy hot compression

Flexible,efficient,and accurate tests for epidemics

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Science China Mathematics 2024年第8期67卷 1881-1898页

作者： Linjiajie Fang bing-Yi Jing Shen Ling Qiyue Wang Qing yang Data Science and Analytics Thrust The Hong Kong University of Science and TechnologyHong KongChina Department of Statistics and Data Science Southern University of Science and TechnologyShenzhen 518055China Department of Mathematics and Statistics Dalhousie UniversityHalifaxNS B 3H 4R 2Canada Department of Mathematics The Hong Kong University of Science and TechnologyHong KongChina

Group testing involves discovering a small subset of distinguished subjects from a large population while efficiently reducing the total number of *** has been widely used for industrial testing,information technology,and biology,especially epidemic ***,in reality,are noisy for the presence of false *** tests are accurate but time-consuming,while others are cheaper but less *** which test to use is constrained by various considerations,such as availability,cost,accuracy,and *** this paper,we propose flexible,efficient,and accurate tests(FEATs).FEATs are based on group testing with simple but careful designs by incorporating ideas such as close contact cliques and repeated *** could dramatically improve the efficiency or accuracy of existing *** example,for accurate but slow tests,the FEAT can improve efficiency multiple times without compromising *** the other hand,for fast but inaccurate tests,the FEAT can sharply reduce the false-negative rate(FNR)and significantly increase *** justifications are *** point out some scenarios where the FEAT can be effectively employed.

关键词： epidemiology control blood testing testing efficiency testing accuracy

Ultra reliability and massive connectivity provision in integrated internet of military things(IoMT)based on tactical datalink

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Defence Technology（防务技术） 2024年第3期33卷 386-398页

作者： Li bing Yating Gu Lanke Hu Li Bowen yang Lihua Jue Wang Yue Yin Northwestern Polytechnical University Xi'an 710072China China Academy of Information and Communications Technology Beijing 100191China China Intelligent and Connected Vehicles(Beijing)Research Institute Co. LtdBeijing 100176China The 20th Research Institute of China Electronic Technology Group Corporation Xi’an 710068China Xidian University Xi'an 710071China

One of the major challenges arising in internet of military things(IoMT)is accommodating massive connectivity while providing guaranteed quality of service(QoS)in terms of ultra-high *** this regard,this paper presents a class of code-domain nonorthogonal multiple accesses(NOMAs)for uplink ultra reliable networking of massive IoMT based on tactical datalink such as Link-16 and joint tactical information distribution system(JTIDS).In the considered scenario,a satellite equipped with Nr antennas servers K devices including vehicles,drones,ships,sensors,handset radios,*** coded modulation,a special form of multiple input multiple output(MIMO)-NOMA is *** discussion starts with evaluating the output signal to interference-plus-noise(SINR)of receiver filter,leading to the unveiling of a closed-form expression for overloading systems as the number of users is significantly larger than the number of devices admitted such that massive connectivity is *** expression allows for the development of simple yet successful interference suppression based on power allocation and phase shaping techniques that maximizes the sum rate since it is equivalent to fixed-point programming as can be *** proposed design is exemplified by nonlinear modulation schemes such as minimum shift keying(MSK)and Gaussian MSK(GMSK),two pivotal modulation formats in IoMT standards such as Link-16 and *** results show that near capacity performance is ***,the performance is obtained using simple forward error corrections(FECs)of higher coding rate than existing schemes do,while the transmit power is reduced by 6 *** proposed design finds wide applications not only in IoMT but also in deep space communications,where ultra reliability and massive connectivity is a keen concern.

关键词： Satellite network Deep space communications Internet of military things Non-orthogonal multiple access MIMO Link-16 JITDS

Weighted Linear Loss Large Margin Distribution Machine for Pattern Classification

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Chinese Journal of Electronics 2024年第3期33卷 753-765页

作者： Ling LIU Maoxiang chu Rongfen GONG Liming LIU Yonghui yang School of Electronic and Information Engineering University of Science and Technology Liaoning

Compared with support vector machine,large margin distribution machine(LDM) has better generalization *** central idea of LDM is to maximize the margin mean and minimize the margin variance *** the computational complexity of LDM is *** order to reduce the computational complexity of LDM,a weighted linear loss LDM(WLLDM) is *** framework of WLLDM is built based on LDM and the weighted linear *** weighted linear loss is adopted instead of the hinge loss in *** modification can transform the quadratic programming problem into a simple linear equation,resulting in lower computational ***,WLLDM has the potential to deal with large-scale *** WLLDM is similar in principle to the LDM algorithm,which can optimize the margin distribution and achieve better generalization *** WLLDM algorithm is compared with other models by conducting experiments on different *** results show that the proposed WLLDM has better generalization performance and faster training speed.

关键词： Training Support vector machines Pattern classification Transforms Fasteners Mathematical models Vectors

Biomineralization and mineralization using microfluidics:A comparison study

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Journal of Rock Mechanics and Geotechnical Engineering 2024年第2期16卷 661-669页

作者： yang Xiao Xiang He Guoliang Ma Chang Zhao Jian chu Hanlong Liu Key Laboratory of New Technology for Construction of Cities in Mountain Area Chongqing UniversityChongqing400045China State Key Laboratory of Coal Mine Disaster Dynamics and Control Chongqing UniversityChongqing400045China School of Civil Engineering Chongqing UniversityChongqing400045China School of Civil and Environmental Engineering Nanyang Technological UniversitySingapore

Biomineralization through microbial process has attracted great attention in the field of geotechnical engineering due to its ability to bind granular materials,clog pores,and seal *** minerals formed by biomineralization are generally the same as that by mineralization,their mechanical behaviors show a significant *** study aims to figure out the differences between biomineralization and mineralization processes by visualizing and tracking the formation of minerals using *** biomineralization and mineralization processes occurred in the Y-shaped sandcontaining microchip that mimics the underground sand *** from different areas in the reaction microchannel of microchips were captured to directly compare the distribution of *** size and numbers from different reaction times were measured to quantify the differences between biomineralization and mineralization processes in terms of crystal *** showed that the crystals were precipitated in a faster and more uncontrollable manner in the mineralization process than that in the biomineralization process,given that those two processes presented similar precipitation *** addition,a more heterogeneous distribution of crystals was observed during the biomineralization *** precipitation behaviors were further explained by the classical nucleation crystal growth *** present microfluidic tests could advance the understanding of biomineralization and provide new insight into the optimization of biocementation technology.

关键词： Microbially induced carbonate precipitation (MICP) Biocementation Crystal Calcium carbonate Nucleation

Quantitative contributions of climate change and human activities to vegetation dynamics in the Zoige Plateau from 2001 to 2020

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Journal of Mountain Science 2024年第9期21卷 3031-3046页

作者： GAO bing LIU Enqin yang yang yang Man YAO yang GUAN Lei FENG Yiwen College of Geography and Planning Chengdu University of TechnologyChengdu 610059China Key Laboratory of Smart Earth Beijing 100029China Sichuan Provincial Soil and Water Conservation Ecological Environment Monitoring Station Chengdu 610041China College of Earth and Planetary Sciences Chengdu University of TechnologyChengdu 610059China

Climate change and human activities such as overgrazing and rapid development of tourism simultaneously affected the vegetation of the Zoige ***,the spatiotemporal variations of vegetation and the relative contributions of climate change and human activities to these vegetation dynamics remain ***,clarifying how and why the vegetation on the Zoige Plateau changed can provide a scientific basis for the sustainable development of the ***,we investigate NDVI trends using the Normalized Difference Vegetation Index(NDVI)as an indicator of vegetation greenness and distinguish the relative effects of climate changes and human activities on vegetation changes by utilizing residual trend analysis and the *** find a tendency of vegetation greening from 2001 to 2020,with significant greening accounting for 21.44%of the entire ***,browning area expanded rapidly after *** temperatures are the primary driver of vegetation changes in the Zoige *** variations and human activities were responsible for 65.57%and 34.43%of vegetation greening,and 39.14%and 60.86%of vegetation browning,respectively,with browning concentrated along the Yellow,Black and White *** to 2001-2010,the inhibitory effect of human activity and climate fluctuations on vegetation grew dramatically between 2011 and 2020.

关键词： Vegetation change Climate change Residual trend analysis Geodetector Human activities Zoige plateau