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Chinese Journal of Chemistry 2024年第20期42卷 2459-2465页

作者： Hanxiao yang Ruoqian fan Daheng wen Mengmeng fan Weiwei fang Jiangsu Co-lnnovation Center of Efficient Processing and Utilization of Forest Resources International Innovation Center for Forest Chemicals and MaterialsCollege of Chemical EngineeringNanjing ForestryUniversity159 Longpan RoadNanjingJiangsu 210037China Shanghai Key Laboratory of Molecular Catalysis and Innovative Materials Department of ChemistryFudan UniversityShanghai 200438China

An efficiently catalytic method toward the synthesis of indolin-2-ones featuring an allylic derived C_(3)-quaternary stereocenter via an intramolecular Heck cyclization/Suzuki coupling of N-substituted-N-(2-bromophenyl)acrylamides and organoboron reagents was successfully developed by using a 1,3-bis(2,6-diisopropylphenyl)acenaphthoimidazol-2-ylidene(AnIPr)-ligated oxazoline *** enabled a very broad substrate scope tolerating different functional groups,electronic properties and steric ***,it revealed a great potential to build diverse heterocycle-fused indoline alkaloids via the same intermediate 3-allyl-1,3-dimethylindolin-2-one.

关键词： C3-Allylic quaternary stereocenter 3 3'-Disubstituted oxindoles Domino reaction Indoline alkaloids Molecular diversity Nitrogen heterocycles Organohalides Palladacyclic N-heterocyclic carbene

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低温煤焦油中酚类化合物的提取利用研究

应用化工 2019年第4期48卷 893-896页

作者：闫厚春王利平范雯阳于雪敏李青松中国石油大学(华东)重质油国家重点实验室山东青岛266580

综述了低温煤焦油中酚类物质的组成和基本性质,并且概述了主要的分离技术,重点讲述了多元溶剂萃取、离子液体萃取、络合萃取、柱层析等新工艺。对各种方法的关键技术进行了分析,比较了传统分离法与新工艺之间的差异。提出了溶剂萃取法... 详细信息

综述了低温煤焦油中酚类物质的组成和基本性质,并且概述了主要的分离技术,重点讲述了多元溶剂萃取、离子液体萃取、络合萃取、柱层析等新工艺。对各种方法的关键技术进行了分析,比较了传统分离法与新工艺之间的差异。提出了溶剂萃取法可以作为一种绿色环保的有效方法,易于实现酚类化合物分离技术成本最低化和效率最大化。

关键词：煤焦油酚类化合物分离传统工艺新工艺

Bounded Evaluation:Querying Big Data with Bounded Resources

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International Journal of Automation and computing 2020年第4期17卷 502-526页

作者： yang Cao wen-Fei fan Teng-Fei Yuan University of Edinburgh Edinburg EH89ABUKUniversity of EdinburghEdinburg EH89ABUK Shenzhen Institute of Computing Sciences Shenzhen UniversityShenzhen 518060China Beijing Advanced Innovation Center for Big Data and Brain Computing Beihang UniversityBeijing 100191China

This work aims to reduce queries on big data to computations on small data,and hence make querying big data possible under bounded resources.A query Q is boundedly evaluable when posed on any big dataset D,there exists a fraction DQ of D such that Q(D)=Q(DQ),and the cost of identifying DQ is independent of the size of *** has been shown that with an auxiliary structure known as access schema,many queries in relational algebra(RA)are boundedly evaluable under the set semantics of *** paper extends the theory of bounded evaluation to RAaggr,i.e.,RA extended with aggregation,under the bag semantics.(1)We extend access schema to bag access schema,to help us identify DQ for RAaggr queries Q.(2)While it is undecidable to determine whether an RAaggr query is boundedly evaluable under a bag access schema,we identify special cases that are decidable and practical.(3)In addition,we develop an effective syntax for bounded RAaggr queries,i.e.,a core subclass of boundedly evaluable RAaggr queries without sacrificing their expressive power.(4)Based on the effective syntax,we provide efficient algorithms to check the bounded evaluability of RAaggr queries and to generate query plans for bounded RAaggr queries.(5)As proof of concept,we extend PostgreSQL to support bounded *** experimentally verify that the extended system improves performance by orders of magnitude.

关键词： Bounded evaluation resource-bounded query processing effective syntax access schema boundedness

Investigation of Maxima Assumptions in Modelling Tropical Cyclone- Induced Hazards in the South China Sea

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China Ocean Engineering 2024年第3期38卷 491-504页

作者： wen Ze-guo WANG Fu-ming WAN Jing yang fan School of Civil Engineering Sun Yat-sen University&Southern Marine Science and Engineering Guangdong Laboratory(Zhuhai)Zhuhai 519082China Guangdong Academy of Safety Science and Technology Guangzhou 510060China Guangdong Key Laboratory of Oceanic Civil Engineering Guangzhou 510275China Advanced Energy Science and Technology Guangdong Laboratory(yangjiang Offshore Wind Energy Laboratory) Yangjiang 529500China

The present study aims to examine the suitability of two commonly used assumptions that simplify modelling metoceanconditions for designing offshore wind turbines in the South China Sea (SCS). The first assumption assumes thatjoint N-year extreme wind and wave events can be independently estimated and subsequently combined. The secondone assumes peak wind and waves can be modelled as occurring simultaneously during a tropical cyclone (TC) *** better understand the potential TC activity, a set of 10000 years synthetic TC events are generated. The wind fieldmodel and the Mike 21 spectral wave model are employed to model the TC-induced hazards. Subsequently, theeffect of the assumptions is evaluated by analyzing the peak structural response of both monopile and semisubmersibleoffshore wind turbines during TC events. The results demonstrate that the examined assumptions are generally *** assessing the implications of these assumptions, valuable insights are obtained, which can inform andimprove the modelling of TC-induced hazards in the SCS region.

关键词： tropical cyclone numerical wave modelling hazards offshore wind turbines structural response

Unmanned Aerial Vehicle Inspection Routing and Scheduling for Engineering Management

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Engineering 2024年第5期36卷 223-239页

作者： Lu Zhen Zhiyuan yang Gilbert Laporte wen Yi Tianyi fan School of Management Shanghai UniversityShanghai 200444China Department of Decision Sciences HEC MontréalMontréalQC H3T 2A7Canada School of Management University of BathBath BA27AYUK Department of Building and Real Estate The Hong Kong Polytechnic UniversityHong Kong 999077China

Technological advancements in unmanned aerial vehicles(UAVs)have revolutionized various industries,enabling the widespread adoption of UAV-based *** engineering management,UAV-based inspection has emerged as a highly efficient method for identifying hidden risks in high-risk construction environments,surpassing traditional inspection *** on this foundation,this paper delves into the optimization of UAV inspection routing and scheduling,addressing the complexity introduced by factors such as no-fly zones,monitoring-interval time windows,and multiple monitoring *** tackle this challenging problem,we propose a mixed-integer linear programming(MILP)model that optimizes inspection task assignments,monitoring sequence schedules,and charging *** comprehensive consideration of these factors differentiates our problem from conventional vehicle routing problem(VRP),leading to a mathematically intractable model for commercial solvers in the case of large-scale *** overcome this limitation,we design a tailored variable neighborhood search(VNS)metaheuristic,customizing the algorithm to efficiently solve our *** numerical experiments are conducted to validate the efficacy of our proposed algorithm,demonstrating its scalability for both large-scale and real-scale *** experiments and a case study based on an actual engineering project are also conducted,providing valuable insights for engineering managers to enhance inspection work efficiency.

关键词： Engineering management Unmanned aerial vehicle Inspection routing and scheduling optimization Mixed-integer linear programming model Variable neighborhood search metaheuristic

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中低温煤焦油的加工利用现状

应用化工 2019年第8期48卷 1904-1907页

作者：闫厚春范雯阳崔鹏廖朝辉王理想李青松中国石油大学(华东)重质油国家重点实验室

介绍了中低温煤焦油的物性和组成,综述了目前中低温煤焦油的加工生产路线,重点讲述了精细化工、加氢和生产沥青路线。对各种工艺的关键技术进行了分析,提出了中低温煤焦油加工利用今后应注意的3点方向:改进煤焦油分离工艺,提高精细化工... 详细信息

介绍了中低温煤焦油的物性和组成,综述了目前中低温煤焦油的加工生产路线,重点讲述了精细化工、加氢和生产沥青路线。对各种工艺的关键技术进行了分析,提出了中低温煤焦油加工利用今后应注意的3点方向:改进煤焦油分离工艺,提高精细化工产品附加值;提高催化剂效率,降低生产成本;提高沥青组分的利用率。

关键词：煤焦油加工利用精细化工加氢沥青生产

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针对神木高挥发性煤成形试验研究

煤炭技术 2016年第3期35卷 276-278页

作者：张金山郭振坤荣令坤孙春宝范雯阳内蒙古科技大学矿业研究院内蒙古包头014010

以陕西神木县粉煤为研究对象,通过加入型煤复合黏结剂,探求其冷热强度并分析其原理。采用单因素实验的方法,对比实验数据,找出成形效果比较优越的配方。研究结果表明,合适的复合黏结剂配比可大大提高型煤冷热强度和热稳定性。对于冷强... 详细信息

以陕西神木县粉煤为研究对象,通过加入型煤复合黏结剂,探求其冷热强度并分析其原理。采用单因素实验的方法,对比实验数据,找出成形效果比较优越的配方。研究结果表明,合适的复合黏结剂配比可大大提高型煤冷热强度和热稳定性。对于冷强度来说,黏结性好的黏结剂与相对黏结性差一些的黏结剂比例在2∶1时黏结性最好。而对于热强度来说,黏结性好的黏结剂与相对黏结性差一些的黏结剂比例在4∶1时黏结性最好。

关键词：黏结剂比例冷强度热强度复合

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淀粉黏结剂在型煤中的影响研究

煤炭技术 2017年第2期36卷 314-315页

作者：郭振坤荣令坤张金山范雯阳孟祥甜内蒙古科技大学矿业研究院内蒙古包头014010 煤炭科学技术研究院有限公司装备分院北京100013

以烟煤为原料,改性的淀粉为黏结剂制备型煤。以型煤的冷强度和热稳定性作为性能检测指标,考察淀粉加入量对型煤的影响。利用扫描电镜对型煤进行了表征,分析了淀粉型煤的成型机理。

关键词：型煤淀粉改性扫描电镜

钠基膨润土对气化型煤制备及型煤热解气体的影响研究

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环境工程 2017年第5期35卷 158-161页

作者：郭振坤贾风军荣令坤范雯阳陈政李博内蒙古科技大学矿业研究院内蒙古包头014010 内蒙古科技大学矿业与煤炭学院内蒙古包头014010

以烟煤为原料,钠基膨润土为粘结剂制备气化型煤。以型煤的冷强度、热稳定性、热强度、浸水强度作为性能检测指标,考察了钠基膨润土加入量对型煤质量的影响。利用扫描电镜,红外光谱和热重分析等手段对型煤进行了表征,分析了钠基膨润土型... 详细信息

以烟煤为原料,钠基膨润土为粘结剂制备气化型煤。以型煤的冷强度、热稳定性、热强度、浸水强度作为性能检测指标,考察了钠基膨润土加入量对型煤质量的影响。利用扫描电镜,红外光谱和热重分析等手段对型煤进行了表征,分析了钠基膨润土型煤的成型机理。结果表明:在钠基膨润土加入量为5%时,气化型煤具有较好的强度和热稳定性;钠基膨润土可通过吸附作用与煤粒充分的接触,形成大量的絮凝体结构单元,包裹煤粒进而提高型煤性能,这个过程发生的是物理变化;在热解型煤时加入膨润土,当热解的温度达到461℃时形成较明显的失重速率峰。

关键词：钠基膨润土气化型煤粘结机理温度

Behavior of phosphorus enrichment in dephosphorization slag at low temperature and low basicity

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International Journal of Minerals,Metallurgy and Materials 2021年第1期28卷 66-75页

作者： Ge-fan Ye Jian yang Run-hao Zhang wen-kui yang Han Sun State Key Laboratory of Advanced Special Steel School of Materials Science and EngineeringShanghai UniversityShanghai 200444China

At low basicity and low temperature, the dephosphorization behavior and phosphorus distribution ratio(LP) between slag and molten steel in the double slag and remaining slag process were studied with a 180 t basic oxygen furnace industrial *** dephosphorization slags with different basicities were quantitatively *** the lower basicity range of 0.9–2.59, both LP and dephosphorization ratio were increased as the basicity of dephosphorization slag *** slag consisted of dark gray P-rich, light gray liquid slag,and white Fe-rich *** increasing basicity, not only did the morphologies of different phases in the dephosphorization slag change greatly, but the area fractions and P2O5 content of the P-rich phase also *** transfer route of P during dephosphorization can be deduced as hot metal → liquid slag phase + Fe-rich phase → P-rich phase.

关键词： dephosphorization basicity phosphorus-rich phase slag converter steelmaking