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Cleaner production of 3.5 valent vanadium electrolyte from ammonium metavanadate by ammonia reduction-sulfuric acid dissolution method

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Tungsten 2024年第3期6卷 555-560页

作者： cheng Wang lan-Jie Li Hao Du College of Chemical Engineering University of Chinese Academy of Sciences Institute of Process Engineering National Engineering Research Center of Green Recycling for Strategic Metal Resources Chinese Academy of Sciences Hesteel Group Company Limited

The vanadium redox flow battery(VRFB) has been widely used in large-scale energy storage areas due to the advantages of long lifespan and high safety. However, the high preparation cost of vanadium electrolyte limits ... 详细信息

关键词： Ammonia

A unified pre-training and adaptation framework for combinatorial optimization on graphs

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Science China Mathematics 2024年第6期67卷 1439-1456页

作者： Ruibin Zeng Minglong Lei Lingfeng Niu lan cheng School of Computer Science and Technology University of Chinese Academy of SciencesBeijing100049China Faculty of Information Technology Beijing University of TechnologyBeijing100124China School of Economics and Management University of Chinese Academy of SciencesBeijing100190China School of Mathematics and Statistics Central South UniversityChangsha410075China

Combinatorial optimization(CO)on graphs is a classic topic that has been extensively studied across many scientific and industrial ***,solving CO problems on graphs through learning methods has attracted great *** deep learning methods,e.g.,graph neural networks(GNNs),have been used to effectively assist the process of solving ***,current frameworks based on GNNs are mainly designed for certain CO problems,thereby failing to consider their transferable and generalizable abilities among different COs on ***,simply using original graphs to model COs only captures the direct correlations among objects,which does not consider the mathematical logicality and properties of *** this paper,we propose a unified pre-training and adaptation framework for COs on graphs with the help of the maximum satisfiability(Max-SAT)*** first use Max-SAT to bridge different COs on graphs since they can be converted to Max-SAT problems represented by standard formulas and clauses with logical *** we further design a pre-training and domain adaptation framework to extract the transferable and generalizable features so that different COs can benefit from *** the pre-training stage,Max-SAT instances are generated to initialize the parameters of the *** the fine-tuning stage,instances from CO and Max-SAT problems are used for adaptation so that the transferable ability can be further *** experiments on several datasets show that features extracted by our framework exhibit superior transferability and Max-SAT can boost the ability to solve COs on graphs.

关键词： combinatorial optimization graph neural networks domain adaptation maximum satisfiability problem

Modifications in aroma characteristics of'Merlot'dry red wines aged in American,French and Slovakian oak barrels with different toasting degrees

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Food Science and Human Wellness 2024年第1期13卷 381-391页

作者： Haocheng Lu Binhao cheng Yibin lan Changqing Duan Fei He Center for Viticulture and Enology College of Food Science and Nutritional EngineeringChina Agricultural UniversityBeijing 100083China Key Laboratory of Viticulture and Enology Ministry of Agriculture and Rural AffairsBeijing 100083China

Aging in oak barrels is widely used in enology which could bring flavor changes and aromatic complexity to *** the present study,the aroma compounds were analyzed from the‘Merlot’dry red wines,which were fermented in two types of fermenters(stainless steel tank and rotated oak barrel)and aged in six types of oak barrels(three geographic origins×two toasting degrees)for different time(0,3,6 and 9 months,respectively).Results showed that 30 volatiles were associated with barrels and increased during oak *** fermenters could influence the intensities of the toast,leathery,smoky,fruity,floral and caramel *** concentration of whisky lactone,eugenol,cis-isoeugenol,and the intensities of the toast and spicy aromas were highest in the wines aged in American oak and were lowest in the wines aged in French oak *** concentrations of guaiacol,syringol,trans-isoeugenol,furfural alcohol,vanilla,cis-whisky lactone enabled the medium toasting barrels to be distinguished from the light toasting *** compounds originating from the barrels could be used to distinguish the types of different barrels,but the other general grape-derived and fermentation-derived volatiles could *** fermenters,oak species and toasting degrees of the barrels all had significant effects on the aroma profiles of the aged‘Merlot’dry red wines,but the influence of the geographic origin was not obvious.

关键词： Wine Aroma Oak Barrel Oak species Toasting degrees Geographic origin Aging

Structured Multi-Head Attention Stock Index Prediction Method Based Adaptive Public Opinion Sentiment Vector

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Computers, Materials & Continua 2024年第1期78卷 1503-1523页

作者： cheng Zhao Zhe Peng Xuefeng lan Yuefeng Cen Zuxin Wang School of Economics Zhejiang University of TechnologyHangzhouChina College of Management Zhejiang University of TechnologyHangzhouChina Informatization Office Zhejiang University of TechnologyHangzhouChina School of Information and Electronic Engineering Zhejiang University of Science&TechnologyHangzhouChina School of Economics and Management Universiti Putra MalaysiaDaerah PetalingNegeri SelangorMalaysia

The present study examines the impact of short-term public opinion sentiment on the secondary market,with a focus on the potential for such sentiment to cause dramatic stock price fluctuations and increase investment *** quantification of investment sentiment indicators and the persistent analysis of their impact has been a complex and significant area of *** this paper,a structured multi-head attention stock index prediction method based adaptive public opinion sentiment vector is *** proposedmethod utilizes an innovative approach to transform numerous investor comments on social platforms over time into public opinion sentiment vectors expressing complex *** then analyzes the continuous impact of these vectors on the market through the use of aggregating techniques and public opinion data via a structured multi-head attention *** experimental results demonstrate that the public opinion sentiment vector can provide more comprehensive feedback on market sentiment than traditional sentiment polarity ***,the multi-head attention mechanism is shown to improve prediction accuracy through attention convergence on each type of input information *** absolute percentage error(MAPE)of the proposedmethod is 0.463%,a reduction of 0.294% compared to the benchmark attention ***,the market backtesting results indicate that the return was 24.560%,an improvement of 8.202% compared to the benchmark *** results suggest that themarket trading strategy based on thismethod has the potential to improve trading profits.

关键词： Public opinion sentiment structured multi-head attention stock index prediction deep learning

Effect of multiple coulomb scattering on the beam tests of silicon pixel detectors

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Nuclear Science and Techniques 2024年第4期35卷 200-207页

作者： lan-Kun Li Ming-Yi Dong Ze Gao Liang-cheng-Long Jin Shu-Jun Zhao School of Physics and Microelectronics Zhengzhou UniversityZhengzhou 450001China State Key Laboratory of Particle Detection and Electronics(Institute of High Energy Physics CAS)Beijing 100049China University of Chinese Academy of Science Beijing 100049China University of South China Hengyang 421001China

In the research and development of new silicon pixel detectors,a collimated monoenergetic charged-particle test beam equipped with a high-resolution pixel-beam telescope is crucial for prototype verification and performance *** the beam energy is low,the effect of multiple Coulomb scattering on the measured resolution of the Device Under Test(DUT)must be considered to accurately evaluate the performance of the pixel chips and *** study aimed to investigate the effect of multiple Coulomb scattering on the measured resolution,particularly at low beam *** were conducted using Allpix^(2) to study the effects of multiple Coulomb scattering under different beam energies,material budgets,and telescope *** simulations also provided the minimum energy at which the effect of multiple Coulomb scattering could be *** with the results of a five-layer detector system tested with an electron beam at DESY,the simulation results were consistent with the beam test results,confirming the reliability of the simulations.

关键词： Silicon Pixel Detectors Beam Telescope Multiple Coulomb Scattering Spatial Resolution

Preparation and Thermal Stability of AlMoON Based Solar Selective Absorption Coating

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Journal of Wuhan University of Technology(Materials Science) 2024年第4期39卷 854-862页

作者：闵捷 YUAN Wenxu CHEN Yufei lan Yapeng YAN Mengdi LIU Hanze cheng Xudong 代路 Hubei Provincial Key Laboratory of Green Materials for Light Industry Hubei University of TechnologyWuhan 430068China Col-laborative Innovation Center of Green Light-weight Materials and Processing Hubei University of TechnologyWuhan 430068China School of Materials and Chemical Engineering Hubei University of TechnologyWuhan 430068China School of Industrial Design Hu-bei University of TechnologyWuhan 430068China State Key Laboratory of Advanced Technology for Materials Synthesis and Process-ing Wuhan University of TechnologyWuhan 430070China Science and Technology on Thermal Energy and Power Laboratory Wuhan Second Ship Design&Research InstituteWuhan 430205China

AlMoON based solar selective absorption coatings were deposited on stainless steel substrate by magnetron *** coatings included infrared reflection layer Mo,absorption layer AlMoN,absorption layer AlMoON and antireflection layer AlMoO from bottom to *** surface of the deposited coatings is flat without obvious *** absorptivity and emissivity are 0.896 and 0.09,respectively,and the quality factor is *** heat treatment at 500℃-36 h,the surface roughness of the coating increases,a small number of cracks and other defects appear,and the broken part is still attached to the coating surface.A certain degree of element diffusion occurs in the coatings,resulting in the decline of the optical properties of the *** absorptivity and emissivity are 0.883 and 0.131,respectively,the quality factor is 7.06,and the PC value is *** coatings do not fail under this condition and have certain thermal stability.

关键词： AlMoON coating preparation thermal stability

Interface Design Strategy for GNS/AZ91 Composites with Semi-Coherent Structure

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Acta Metallurgica Sinica(English Letters) 2024年第3期37卷 467-483页

作者： Jing-Peng Xiong Yi-Qi Zeng Jin-Long Liu Wei-cheng Wang lan Luo Yong Liu Key Laboratory of Lightweight and High Strength Structural Materials of Jiangxi Province School of Advanced ManufacturingNanchang UniversityNanchang 330031China School of Physics and Materials Science Nanchang UniversityNanchang 330031China

The interfacial structure plays an important role in the mechanical properties of magnesium matrix composite(MMCs)reinforced with graphene nanosheet(GNS)due to their poor wettability with the Mg *** interface design strategy was proposed to form the semi-coherent interfacial structure with superior bonding *** lattice mismatch and interfacial bonding strength between Mg/rare earth oxide/carbon were utilized as key characteristics to evaluate the interfacial *** oxide(La2O3)was selected as the intermediate candidate due to its low lattice mismatch and high interfacial bonding *** identify the interfacial structure of Mg/La2O3/graphene,first-principles calculations were conducted to calculate the ideal work of separation and electronic structure of the *** demonstrated the presence of strong ionic and covalent interactions at the interface,which theoretically verified the strong interfacial bonding strength among Mg/La2O3/graphene *** experimentally validate the interface strength,MMCs with the interface structure of Mg/La2O3/GNS were *** formation of in-situ La2O3 led to the successful attainment of semi-coherent structures between Mg/La2O3 and La2O3/GNS,resulting in high strength and good ductility of the ***,this work proposes a new approach to interface design in MMCs with an enhancement of mechanical properties.

关键词： Interface design strategy Magnesium matrix composite Graphene nanosheets Semi-coherent interface Mechanical properties

NO_(x) reduction against alkali poisoning over Ce(SO_(4))_(2)-V_(2)O_(5)/TiO_(2) catalysts by constructing the Ce^(4+)-SO_(4)^(2−)pair sites

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Chinese Chemical Letters 2024年第5期35卷 355-360页

作者： Shuangxi Li Huijun Yu Tianwei lan Liyi Shi Danhong cheng Lupeng Han Dengsong Zhang State Key Laboratory of Advanced Special Steel School of Materials Science and EngineeringInternational Joint Laboratory of Catalytic ChemistryCollege of SciencesShanghai UniversityShanghai 200444China

Commercial V_(2)O_(5)-based catalysts have been successfully applied in NH_(3) selective catalytic reduction(NH_(3)-SCR)of NO_(x) from power stations,but their poor alkali-resistance restrains the wider application in nonelectrical *** this study,NO_(x) reduction against alkali poisoning over V_(2)O_(5)/TiO_(2) is greatly improved via Ce(SO_(4))_(2) *** has been originally demonstrated that Ce^(4+)-SO_(4)^(2−)pair sites play crucial roles in improving NO_(x) reduction against alkali poisoning over V_(2)O_(5)/TiO_(2) *** strong interaction between V species and Ce sites of Ce^(4+)-SO_(4)^(2−)pairs triggers the reaction between NH_(4)^(+) species and gaseous NO via Eley-Rideal(E-R)reaction *** K-poisoning,the SO_(4)^(2−)sites of Ce^(4+)-SO_(4)^(2−)pairs as protective sites strongly bond with K and thus maintain the high reaction efficiency via the E-R reaction *** work demonstrates an effective strategy to enhance NO_(x) reduction against alkali poisoning over catalysts via constructing Ce^(4+)-SO_(4)^(2−)pair sites,contributing to developing alkali-resistant SCR catalysts for practical application in nonelectrical industries.

关键词： Air pollution control Selective catalytic reduction NOx reduction Alkali poisoning Ce(SO_(4))_(2)

Numerical investigation on ball-sealers transport and diversion performance in shale gas horizontal well based on semi-resolved CFDDEM

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PARTICUOLOGY 2024年第10期93卷 137-153页

作者： Huang, Yinjian Zhao, Jinzhou Ren, lan Lin, Ran Wu, Jianfa Shen, cheng Wu, Jianjun Li, Bing Southwest Petr Univ Natl Key Lab Oil & Gas Reservoir Geol & Exploitat Chengdu 610500 Peoples R China Tianfu Yongxing Lab Chengdu 610213 Peoples R China PetroChina Southwest Oil & Gas Field Co Shale Gas Res Inst Chengdu 610056 Peoples R China PetroChina Coalbed Methane Co Ltd Xian 710082 Peoples R China

In the staged multi-cluster fracturing of shale gas horizontal wells, ball sealers are used to ensure uniform fluid distribution among clusters, a strategy that is both cost-effective and operationally beneficial. Despite these advantages, comprehending the ball sealers' dynamics within the wellbore and their plugging behavior at perforations is still challenging. This complexity results in prediction difficulties regarding their diversion efficiency. To address this, our study utilized a semi-resolved CFD-DEM model based on kernel approximation to simulate the behavior of medium-sized ball sealers in single and multiple cluster scenarios. Our findings from a single cluster scenario reveal that the plugging probability is co-determined by velocity gradients in the fluid ingestion area near the perforation, backflow region, and inertial forces of the ball sealers. As the critical flow rate is achieved, the plugging probability negatively correlated with fluid viscosity and displacement, and positively correlated with the perforation flow ratio (PFR), the difference in particle-fluid density, ball sealer 's diameter, and the ball sealer 's offset from the pipeline center. Temporary plugging control efficiency was used to evaluate the flow balance effect among multiple clusters. The results indicate that an increased number of ball sealers enhances the fault tolerance during the temporary plugging process. Nevertheless, excessive ball sealers might undermine the temporary plugging control efficiency, as perforations with lower fluid inflow rates are unexpectedly plugging. Higher differences in fluid injection rates between clusters led to increased efficiency in temporary plugging control. Premature deployment of ball sealers cannot effectively plug perforations with marginally higher fluid inflow rates, but instead accidently plug intermediate clusters with lower fluid inflow rates. These findings offer a theoretical basis for optimizing the design of ball sealers. (c

关键词： Gas shale Horizontal wells Ball sealer Semi-resolved CFD-DEM Diversion DEM SIMULATION PARTICLES FLOW MODEL EFFICIENCY