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High-chromium vanadium-titanium magnetite all-pellet integrated burden optimization and softening-melting behavior based on flux pellets

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International Journal of Minerals,Metallurgy and Materials 2024年第3期31卷 498-507页

作者： Bojian Chen Tao Jiang jing Wen Guangdong Yang Tangxia yu Fengxiang Zhu Peng Hu School of Metallurgy Northeastern UniversityShenyang 110819China Key Laboratory for Ecological Metallurgy of Multimetallic Mineral(Ministry of Education) Northeastern UniversityShenyang 110819China Liaoning Key Laboratory for Metallurgical Sensor and Technology Shenyang 110819China State key laboratory of vanadium and titanium resources comprehensive utilization Panzhihua 617000China

High-chromium vanadium-titanium magnetite(HVTM)is a crucial polymetallic-associated resource to be *** allpellet operation is a blast furnace trend that aims to reduce carbon dioxide emissions in the *** referencing the production data of vanadium-titanium magnetite blast furnaces,this study explored the softening-melting behavior of high-chromium vanadium-titanium magnetite and obtained the optimal integrated burden based on flux *** results show that the burden with a composition of 70wt%flux pellets and 30wt%acid pellets exhibits the best softening-melting *** comparison to that of the single burden,the softening-melting characteristic temperature of this burden composition was *** melting interval first increased from 307 to 362℃and then decreased to 282℃.The maximum pressure drop(ΔPmax)decreased from 26.76 to 19.01 *** permeability index(S)dropped from 4643.5 to 2446.8 kPa·℃.The softening-melting properties of the integrated burden were apparently *** acid pellets played a role in withstanding load during the softening *** flux pellets in the integrated burden exhibited a higher slag melting point,which increased the melting temperature during the melting *** slag homogeneity and the TiC produced by over-reduction led to the gas permeability deterioration of the single *** segregation of the flux and acid pellets in the HVTM proportion and basicity mainly led to the better softening-melting properties of the integrated burden.

关键词： high-chromium vanadium-titanium magnetite softening-melting properties all pellets integrated burden flux pellets

A fungal CYP from Beauveria bassiana with promiscuous steroid hydroxylation capabilities

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Chinese Chemical Letters 2024年第5期35卷 218-222页

作者： yu Peng yue Wang Tian-Jiao Chen jing-jing Chen Jin-Ling Yang Ting Gong Ping Zhu State Key Laboratory of Bioactive Substance and function of Natural Medicines NHC Key Laboratory of Biosynthesis of Natural ProductsCAMS Key Laboratory of Enzyme and Biocatalysis of Natural DrugsInstitute of Materia MedicaChinese Academy of Medical Sciences&Peking Union Medical CollegeBeijing 100050China

Hydroxylation of steroid core is critical to the synthesis of steroid *** sp^(3) C-H hydroxylation is challenging through chemical catalysis,alternatively,fungal biotransformation offers a possible solution to this ***,mining and metabolic engineering of cytochrome P450 monooxygenases(CYPs)is usually regarded as a more eco-friendly and efficient ***,we report the mining and identification of a new steroid CYP(CYP68BE1)from Beauveria bassiana by transcriptomics,heterologous expression,in vivo and in vitro functional *** catalytic promiscuity of CYP68BE1 was explored,and CYP68BE1 showed promiscuously and catalytically versatile,which is qualified for monohydroxylation on C11α,C1α,C6βand dihydroxylation on C1β,11αand C6β,11αof six steroids,leading to the production of key steroid intermediates required in the industrial synthesis of some indispensable steroid *** dynamics simulations were performed,revealing the molecular basis of different binding orientations of CYP68BE1 with different *** discovery of CYP68BE1 offers a promising biocatalyst for enriching the steroid structural and functional diversity,which also can be applied to biosynthesize valuable steroid drug intermediates.

关键词： fungal CYPs Steroid hydroxylase Beauveria bassiana Promiscuous biocatalyst Molecular dynamics

MOF-derived Cu embedded into N-doped mesoporous carbon as a robust support of PdAu nanocatalysts for ethanol electrooxidation

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Rare Metals 2024年第3期43卷 1083-1094页

作者： yu-fu Huang Peng Wu Jun-Ping Tang Jian Yang jing Li Shuai Chen Xue-Ling Zhao ChengChen Bin-Wei Zhang Yan-yun Ma Wei-Heng Shi Dong-Hai Lin Shi-Gang Sun School of Energy and Materials Shanghai Engineering Research Center of Advanced Thermal Functional MaterialsShanghai Key Laboratory of Engineering Materials Application and EvaluationShanghai Polytechnic UniversityShanghai201209China State Key Laboratory of Physical Chemistry of Solid Surfaces Department of ChemistryCollege of Chemistry and Chemical EngineeringXiamen UniversityXiamen361005China School of Chemistry and Chemical Engineering Chongqing UniversityChongqing401331China Center of Advanced Energy Technology and Electrochemistry Institute of Advanced Interdisciplinary StudiesChongqing UniversityChongqing400044China Institute of functional Nano&Soft Materials(fuNSOM) Jiangsu Key Laboratory for Carbon-Based Functional Materials&DevicesSoochow UniversitySuzhou215123China Department of Materials Science and Engineering Drexel UniversityPhiladelphiaPA19104USA

Metal-organic frameworks(MOFs)h ave attracted widespread attention due to their large surface area and porous *** designing the nanostructures of MOFs to promote their application in ethanol electrooxidation is still a ***,a novel Cu-NCNs(Cu-nitrogen-doped carbon nanotubes)support was synthesized by pyrolysis of melamine(MEL)and Cu-ZIF-8 together,and then,Pd-Au nanoalloys were loaded by sodium borohydride reduction method to prepare PdAu@Cu-NCNs *** generating mesoporous carbon with high specific surface area and favorable electron and mass transport can be used as a potential excellent carrier for PdAu *** addition,the balance of catalyst composition and surface structure was tuned by controlling the content of Pd and ***,the best-performed Pd_(2)Au_(2)@Cu-NCN-1000-2(where 1000 means the carrier calcination temperature,and 2 means the calcination constant temperature time)catalyst exhibits better long-term stability and electrochemical activity for ethanol oxidation in alkaline media(4.80 A·mg^(-1)),which is 5.05 times higher than that of commercial Pd/C(0.95 A·mg^(-1)).Therefore,this work is beneficial to further promoting the application of MOFs in direct ethanol fuel cells(DEFCs)and can be used as inspiration for the design of more efficient catalyst support structures.

关键词： Metal-organic frameworks(MOFs) N-doped Mesoporous carbon PdAu Ethanol electrooxidation

Understanding livelihood vulnerability:a perspective from Western Sichuan’s ethnic rural settings

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Journal of Mountain Science 2024年第2期21卷 380-396页

作者： yu Yongqian jing Zheng WANG Yan QIU Xiaoping YANG Xueting XU yun School of Geography and Resource Science Sichuan Normal UniversityChengdu 610101China Key Laboratory of land Resources Evaluation and Monitoring in Southwest Ministry of EducationSichuan Normal UniversityChengdu 610101China Sichuan County Economic Development Research Center Mianyang Normal UniversityMianyang 621000China Institute of Mountain Hazards and Environment Chinese Academy of SciencesChengdu 610041China

To explore the livelihood status and key influencing factors of rural households in the minority areas,we collected flat data from 284 rural households in 32 villages across 12 counties of Western Sichuan from 2021 to *** conducted participatory household survey on the livelihood status of the rural households and try to identify the key factors to influence their livelihood vulnerability using multiple linear *** results showed that:the livelihood situation of the rural households is relatively *** vulnerability varies significantly with the income levels,education levels,and income *** vulnerability of farm households,categorized from low to high livelihood types,follows the sequence:non-agricultural dominant households,non-agricultural households,agricultural dominant households,and pure agricultural *** degree of damage to the natural environment,education costs,loan opportunities,the proportion of agricultural income to annual household income,and the presence of sick people in the household have significant positive effects on the livelihood vulnerability index(LVI)of rural households;while help from relatives and friends,net income per capita,household size,household education,agricultural land area,participation in industrial organizations,number of livestock,purchase of commercial houses,drinking water source,and self-supply of food have significant negative *** on the findings,we believe that local rural households operate in a complex livelihood system and recommend continuous interventions targeting key influences to provide empirical research support for areas facing similar situations.

关键词： Livelihood Vulnerability Rural households Ethnic areas

GraphFlow+:Exploiting Conversation Flow in Conversational Machine Comprehension with Graph Neural Networks

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Machine Intelligence Research 2024年第2期21卷 272-282页

作者： jing Hu Lingfei Wu yu Chen Po Hu Mohammed J.Zaki School of Computer Science Central China Normal UniversityWuhan 430079China Pinterest San Francisco 94016USA Meta Mountain View 94039USA Rensselaer Polytechnic Institute Troy 12180USA

The conversation machine comprehension(MC)task aims to answer questions in the multi-turn conversation for a single ***,recent approaches don’t exploit information from historical conversations effectively,which results in some references and ellipsis in the current question cannot be *** addition,these methods do not consider the rich semantic relationships between words when reasoning about the passage *** this paper,we propose a novel model GraphFlow+,which constructs a context graph for each conversation turn and uses a unique recurrent graph neural network(GNN)to model the temporal dependencies between the context graphs of each ***,we exploit three different ways to construct text graphs,including the dynamic graph,static graph,and hybrid graph that combines the *** experiments on CoQA,QuAC and DoQA show that the GraphFlow+model can outperform the state-of-the-art approaches.

关键词： Conversational machine comprehension(MC) reading comprehension question answering graph neural networks(GNNs) natural language processing(NLP)

Robust tantalum tuned perovskite oxygen electrode for reversible protonic ceramic electrochemical cells

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Rare Metals 2024年第7期43卷 3055-3065页

作者： yu-Shi Feng yu Shen Fang Wang Chuan Tian Qin-Yi Hu Qian Duan jing-Wei Li Di Bao School of Materials Science and Engineering Changchun University of Science and Technology Zhongshan Institute of Changchun University of Science and Technology State Key Laboratory of Rare Earth Resource Utilization Changchun Institute of Applied Chemistry Chinese Academy of Sciences Key Laboratory of Preparation and Applications of Environmental Friendly Materials Ministry of EducationJilin Normal University

Perovskite oxides with diverse composition and structure have exhibited grand advances in boosting the oxygen reduction and evolution reaction（ORR/OER）,which are essential for the reversible protonic ceramic electrochemical cell（R-PCEC） toward the sustainable hydrogen production and ***,enhancement of their activity and stability remains ***,we develop the Ta-regulated BaCo0.7Fe0.3O3-δperovskite oxygen electrode(Ba(Co0.7Fe0.3)1-xTaxO3-δ)with abundant oxygen defects and achieve the simultaneous enhancement in the electrocatalytic activity and stability toward ORR and ***-fabricated R-PCEC with(Ba(Co0.7Fe0.3)0.9Ta0.1O3-δ)（BCFT10） oxygen electrode performs high power density of 1.47 W·cm-2at 650℃ in fuel cell mode,and the current density is up to-2.11 A·cm-2at 1.4 V at 650℃ in electrolysis mode,as well as the good stability in both the fuel cell and electrolysis ***,the cell also demonstrates a stable cycling operation between fuel cell and electrolysis mode,suggesting a great potential of BCFT10 as oxygen electrode material for R-PCECs.

关键词： Reversible protonic ceramic electrochemical cells Perovskite oxide Oxygen electrode Ta element doping Oxygen defects

Rheological study of methane gas hydrates in the presence of micron-sized sand particle

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Chinese Journal of Chemical Engineering 2024年第6期70卷 149-161页

作者： Bohui Shi Shangfei Song yuchuan Chen Shunkang fu Lihao Liu Xinyao Yang Haihao Wu Guangjin Chen jing Gong National Engineering Research Center of Oil and Gas Pipeline Transportation Safety MOE Key Laboratory of Petroleum EngineeringBeijing Key Laboratory of Urban Oil and Gas Distribution TechnologyChina University of Petroleum-BeijingBeijing 102249China China's Oil and Gas Exploration and Development Company(CNODC) Beijing 100034China China National Petroleum Corporation Mozambique LDA MaputoMozambique PipeChina West East Pipeline Company Shanghai 200122China

Natural gas hydrates,intricate crystalline structures formed by water molecules and small gas molecules,have emerged as a significant and globally impactful clean energy ***,their commercial exploitation faces challenges,particularly operational disruptions caused by sand-related *** the rheological properties of hydrate slurry,especially in the presence of micron-sized sand particles,is imperative for ensuring the flow assurance of subsea hydrate *** study extensively investigates the rheological properties of sand-containing hydrate *** findings reveal that these slurries exhibit non-Newtonian fluid characteristics,including yield stress,thixotropy,and shear-thinning ***-like elastic features are observed in sand-containing hydrate slurries before yielding,transitioning to viscous behavior after *** with a minimal amount of sand,both static yield stress and yield strain experience substantial changes,correlating with the increase in sand *** research conclusively establishes the thixotropic nature of sand-hydrate slurries,where the viscosity decay rate is directly influenced by the shear *** insights aim to contribute comprehensively to the development of effective flow assurance strategies,ensuring the safe and stable operation of subsea hydrate exploitation.

关键词： Natural gas hydrate production Sand-containing hydrate slurries Yield stress Thixotropy Shear-thinning behavior

Efficient removal of Cr(VI) by polydopamine-modified lignin from aqueous solution: Batch and XAFS studies

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Water Science and Engineering 2024年第1期17卷 51-61页

作者： Xiao-jie Guo Wei-kang fu jing-yuan Ma Bo-jun Xi Chen Wang Meng-yao Guan College of Materials and Environmental Engineering Hangzhou Dianzi UniversityHangzhou 310018China College of Textile and Garment Shaoxing UniversityShaoxing 312000China Shanghai Synchrotron Radiation Facility Shanghai Advanced Research InstituteChinese Academy of SciencesShanghai 201204China

Lignocellulose has the potential to become a bio-based adsorbent due to its biodegradability and *** this study,a novel polydopamine functionalized-lignin(lignin@PDA),prepared via self-polymerization of dopamine(PDA)on lignin,was used as a bio-based adsorbent for rapid scavenging of hexavalent chromium(Cr(VI)).The morphology,functional groups,crystalline structure,and chemical composition of lignin@PDA were characterized with a scanning electron microscope-energy dispersive spectrometer,Fourier transform infrared spectroscopy,X-ray diffraction,and X-ray photoelectron *** Cr(VI)adsorption process of lignin@PDA was studied using batch experiments as a function of pH,ionic strength,adsorbent dose,and contact time at room *** adsorption rate of lignin@PDA was five times greater than that of the unmodified lignin,with a maximum adsorption capacity of 102.6 mg/g in an acidic *** adsorption of Cr(VI)on lignin@PDA fit the pseudo-secondorder equation and the Freundlich model,indicating that the adsorption process was mainly dominated by chemisorption and surface *** thermodynamic parameters showed that adsorption of Cr(VI)on lignin@PDA was an endothermic and spontaneous *** X-ray absorption fine structure results showed that sorption and reduction of Cr(VI)into Cr(II)occurred simultaneously on ***,PDA coating not only improved the reactivity of lignin but also promoted the complete reduction of Cr(VI)by *** to these results,polydopamine functionalized-lignin is a promising bio-based adsorbent for immobilization of Cr(VI)from wastewater.

关键词： Lignin Polydopamine Hexavalent chromium EXAFS Adsorption mechanism

Span-based joint entity and relation extraction augmented with sequence tagging mechanism

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Science China(Information Sciences) 2024年第5期67卷 84-98页

作者： Bin JI Shasha LI Hao XU Jie yu Jun MA Huijun LIU jing YANG College of Computer National University of Defense Technology

Span-based joint extraction simultaneously conducts named entity recognition(NER) and relation extraction(RE) in a text span form. However, since previous span-based models rely on span-level classifications, they cannot benefit from token-level label information, which has been proven advantageous for the task. In this paper, we propose a sequence tagging augmented span-based network(STSN), a spanbased joint model that can make use of token-level label information. In STSN, we construct a core neural architecture by deep stacking multiple attention layers, each of which consists of three basic attention *** the one hand, the core architecture enables our model to learn token-level label information via the sequence tagging mechanism and then uses the information in the span-based joint extraction; on the other hand, it establishes a bi-directional information interaction between NER and RE. Experimental results on three benchmark datasets show that STSN consistently outperforms the strongest baselines in terms of F1,creating new state-of-the-art results.

关键词： joint extraction named entity recognition relation extraction span sequence tagging mechanism