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Atmospheric and Oceanic Science Letters 2024年第4期17卷 58-64页

作者： yueqi gao Siyu Wang Zhaolei Zhang Wenxuan Yu Shuai Wang Shengqiang Zhu Peng Wang Yan Li Yele Sun Hongliang Zhang Shanghai Key Laboratory of Atmospheric Particle Pollution and Prevention Department of Environmental Science&EngineeringFudan UniversityShanghaiChina Department of Atmospheric and Oceanic Sciences Fudan UniversityShanghaiChina Shanghai Key Laboratory of Ocean-land-atmosphere Boundary Dynamics and Climate Change ShanghaiChina IRDR ICoE on Risk Interconnectivity and Governance on Weather/Climate Extremes Impact and Public Health Fudan UniversityShanghaiChina State Key Laboratory of Atmospheric Boundary Layer Physics and Atmospheric Chemistry Institute of Atmospheric PhysicsChinese Academy of SciencesBeijingChina College of Earth and Planetary Sciences University of Chinese Academy of SciencesBeijingChina Institute of Eco-Chongming ShanghaiChina

自2013年起中国空气质量虽改善,但华北平原(NCP)重污染仍存在且二次污染加剧,而人们对其成因和变化了解有限.本研究利用2018-2022年数据,借助CMAQ模型探讨此污染响应.结果显示,在2018-2022年间,PM_(2.5)浓度显著下降31%-37%,O_(3)和NO_... 详细信息

自2013年起中国空气质量虽改善,但华北平原(NCP)重污染仍存在且二次污染加剧,而人们对其成因和变化了解有限.本研究利用2018-2022年数据,借助CMAQ模型探讨此污染响应.结果显示,在2018-2022年间,PM_(2.5)浓度显著下降31%-37%,O_(3)和NO_(2)的年下降速率分别为1%和0.5%SIA和SOA也显著减少,每年分别减少9%和6%PM_(2.5)主要因排放减少而下降,而O_(3)则受气象影响而波动.硫酸盐和铵下降的主因是减排,而硝酸盐对气象变化敏感排放和气象变化对SOA的总体减少同样重要,但人为SOA对排放控制敏感生物SOA易受气象变化影响.研究强调了控制人为排放对缓解NCP地区夏季二次污染的重要性.

关键词： PM_(2.5) 二次污染物人为排放气象华北平原

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他克莫司的分离提纯研究

中国抗生素杂志 2024年第2期49卷 175-180页

作者：王圆超赵辉王月谷岩翡高月麒李晓露微生物药物国家工程研究中心石家庄市微生物药物技术创新中心华北制药集团新药研究开发有限责任公司石家庄052165 华北制药华胜有限公司石家庄052160

目的开发一种他克莫司的分离提纯工艺。方法采用离子交换树脂脱色除杂、纳滤、结晶等手段得到高质量的他克莫司粗粉,再经反相色谱硅胶层析、复合溶液结晶,得到符合USP标准的他克莫司精粉。结果优选的脱色树脂为D002,所得他克莫司粗... 详细信息

目的开发一种他克莫司的分离提纯工艺。方法采用离子交换树脂脱色除杂、纳滤、结晶等手段得到高质量的他克莫司粗粉,再经反相色谱硅胶层析、复合溶液结晶,得到符合USP标准的他克莫司精粉。结果优选的脱色树脂为D002,所得他克莫司粗粉效价大于800μg/mg,二氢他克莫司含量小于4%;该粗粉经UniSil C8Ultra Plus层析纯化,精粉含量大于99.5%,最大单杂小于0.1%。结论该工艺操作简单、能耗低、收率高,适于他克莫司的产业化应用。

关键词：他克莫司分离提纯离子交换树脂层析结晶

Highly dispersed nickel boosts catalysis by Cu/SiO_(2) in the hydrogenation of CO_(2)-derived ethylene carbonate to methanol and ethylene glycol

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Chinese Journal of Chemical Engineering 2022年第3期35卷 77-85页

作者： Youwei Yang Jingyu Zhang yueqi gao Busha Assaba Fayisa Antai Li Shouying Huang Jing Lv Yue Wang Xinbin Ma Key Laboratory for Green Chemical Technology of Ministry of Education Collaborative Innovation Center of Chemical Science and EngineeringSchool of Chemical Engineering and TechnologyTianjin UniversityTianjin 300072China Joint School of National University of Singapore and Tianjin University International Campus of Tianjin UniversityFuzhou 350207China

The efficient hydrogenation of CO_(2)-derived ethylene carbonate(EC)to yield methanol(MeOH)and ethylene glycol(EG)is a key process for indirect conversion of CO_(2)to ***,a high H_(2)/EC molar ratio during the hydrogenation process(usually as 180-300)is generally required to achieve good catalytic performance,resulting in high cost and energy consumption for H_(2)circulation in the promising industrial ***,we prepared a series of Ni-modified Cu/SiO_(2)catalysts and explored the effects of synthesis methods and Ni contents on catalytic performance under different H_(2)/EC molar *** Cu/SiO_(2)catalyst with 0.2%(mass)Ni loading prepared by co-ammonia evaporation method exhibited above 99%conversion of EC,91%and 98%selectivity to MeOH and EG respectively at H_(2)/EC ratio of *** no significant deactivation was observed within 140 h at a lower H_(2)/EC of *** is demonstrated that a few of Ni addition could not only promote Cu dispersion and increase surface Cu^(+) species due to the strong interaction between Cu and Ni species,but also form uniformly-dispersed CuNi alloy species and thus enhance the adsorption and dissociation of H_(2).But the excess Ni species would aggregate and segregate to cover partial surface of Cu nanoparticles,leading to a significantly drop of catalytic performance in EC *** insights may provide guidance for further design of catalysts for the ester hydrogenation reactions.

关键词： Cu-based catalyst Ethylene carbonate Methanol Hydrogenation Carbon dioxide

Pt-modulated Cu/SiO_(2) catalysts for efficient hydrogenation of CO_(2)-derived ethylene carbonate to methanol and ethylene glycol

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Chinese Journal of Chemical Engineering 2022年第1期35卷 366-373页

作者： Busha Assaba Fayisa Yushan Xi Youwei Yang yueqi gao Antai Li Mei-Yan Wang Jing Lv Shouying Huang Yue Wang Xinbin Ma Key Laboratory for Green Chemical Technology of Ministry of Education Collaborative Innovation Center of Chemical Science and EngineeringSchool of Chemical Engineering and TechnologyTianjin UniversityTianjin 300072China Zhejiang Institute of Tianjin University Ningbo 315201China Joint School of National University of Singapore and Tianjin University International Campus of Tianjin UniversityFuzhou 350207China

Copper-based catalysts were widely used in the heterogeneous selective hydrogenation of ethylene carbonate(EC),a key step in the indirect conversion of CO_(2) to ***,a high H_(2)/EC molar ratio in feed is required to achieve favorable activity and the methanol selectivity still needs to be ***,we fabricated a series of Pt-modulated Cu/SiO_(2) catalysts and investigated their catalytic performance for hydrogenation of EC in a fixed bed *** modulating the Pt amount,the optimal 0.2Pt-Cu/SiO_(2) catalyst exhibited the highest catalytic performance with99%EC conversion,over 98%selectivity to ethylene glycol and 95.8%selectivity to methanol at the H_(2)/EC ratio as low as 60 in *** addition,0.2Pt-Cu/SiO_(2) catalyst showed excellent stability for 150 h on stream over different H_(2)/EC ratios of *** is demonstrated a proper amount of Pt could significantly lower the H_(2)/EC molar ratio,promote the reducibility and dispersion of copper,and also enhance surface density of Cu+*** could be due to the strong interaction of Cu and Pt induced by formation of alloyed Pt single atoms on the Cu ***,a relatively higher amount of Pt would deteriorate the catalytic activity,which could be due to the surface coverage and aggregation of active *** findings may enlighten some fundamental insights for further design of Cu-based catalysts for the hydrogenation of carbon–oxygen bonds.

关键词： CO_(2) Ethylene carbonate Hydrogenation Pt-Cu/SiO_(2)catalyst Ethylene glycol Methanol

基于行波效应的大跨度钢-混凝土组合拱桥地震响应分析

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公路交通技术 2015年第1期31卷 45-50页

作者：高月琪招商局重庆交通科研设计院有限公司重庆400067

研究大跨度结构的地震响应时,有必要考虑地震波的行波效应。针对一种特殊的钢-混凝土组合拱桥进行地震响应研究。以重庆市万县长江大桥为建模依据,使用大型通用有限元软件sap2000建立跨径为420 m的钢-混凝土组合拱桥计算模型,并对该模... 详细信息

研究大跨度结构的地震响应时,有必要考虑地震波的行波效应。针对一种特殊的钢-混凝土组合拱桥进行地震响应研究。以重庆市万县长江大桥为建模依据,使用大型通用有限元软件sap2000建立跨径为420 m的钢-混凝土组合拱桥计算模型,并对该模型多种激励状态进行分析。在一致激励状态下进行几何非线性时程分析,并基于多点激振理论和相对位移法,采用7种不同的时差对计算模型进行行波效应下的地震响应分析。对比研究表明行波效应对大跨度桥梁结构地震响应有很大影响。

关键词：大跨度钢混组合拱桥非线性时程分析行波效应 sap2000

Application Strategy of Carbon Fiber Composite Materials in Bridge Reconstruction Project

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Journal of Architectural Research and Development 2021年第1期5卷 1-3页

作者： yueqi gao China Merchants Chongqing Communications Technology Research&Design Institute CO .LTD.Chongqing 400067China

Initially,the materials used in the process of bridge construction were mainly wood,stone,etc.,and gradually the concrete,steel and other types of special materials currently in-use were *** the current vigorous development of science,technology and social economy in China,the development of bridge projects has also been accelerated to a large *** recent years,China has not only studied on how to strengthen the performance of concrete,steel and other materials in bridge projects,but also the performance of the recently developed smart,nano-,fibrous and other types of *** paper focuses on the application strategy of carbon fiber composite materials in bridge reconstruction projects to serve as a reference.

关键词： Carbon fiber Composite material Bridge reconstruction

Design and Construction Strategy of Arched Continuous Rigid-frame Bridge

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Journal of World Architecture 2021年第1期5卷 5-7页

作者： yueqi gao CMCU Engineering CO. Ltd.Chongqing 400067China

With the current rapid development of urbanization in China,people's living standards have been greatly *** the context of such a development background,the requirements for road traffic are getting more stringent,especially for bridge *** arched continuous rigid-frame bridge was developed under this social *** advantage of the bridge lies in the design of a bridge model that integrates various functions such as transportation,landscape,and *** on the above,this paper first refers to the case to analyze the design and construction strategy of the arched continuous rigid-frame bridge,in hope of providing a valuable reference for relevant personnel.

关键词： Arch Continuous steel structure Bridge design Construction

Record-high efficiency perovskite LEDs achieved by accelerating radiative recombination

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Science China Materials 2024年第9期67卷 3039-3040页

作者： Feng gao Department of Physics Chemistry and BiologyLinköping UniversityLinköping58183Sweden

Light-emitting diodes(LEDs)have revolutionized the lighting and displays due to their superior energy *** increasing demand for more efficient and brighter thin-film LEDs in flat-panel displays and solid-state lighting applications has driven extensive research into perovskite materials,which show great promise for high brightness and efficiency.

关键词： lighting radiative high

Stress tensor determination by modified hydraulic tests on pre-existing fractures:Method and stress constraints

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Journal of Rock Mechanics and Geotechnical Engineering 2024年第5期16卷 1637-1648页

作者： Guiyun gao Chenghu Wang Ke gao National Institute of Natural Hazards Ministry of Emergency Management of ChinaBeijing100085China Beijing Engineering Research Center of Earthquake Observation Beijing100085China Key Laboratory of Compound and Chained Natural Hazards Dynamics Ministry of Emergency Management of ChinaBeijing100085China Department of Earth and Space Sciences Southern University of Science and TechnologyShenzhen518055China

The hydraulic testing of pre-existing fractures(HTPF)is one of the most promising in situ stress measurement methods,particularly for three-dimensional stress tensor ***,the stress tensor determination based on the HTPF method requires at least six tests or a minimum of 14-15 tests(under different conditions)for reliable *** this study,we modified the HTPF method by considering the shear stress on each pre-existing fracture,which increased the number of equations for the stress tensor determination and decreased the number of tests *** shear stresses were attributed to different fractures by random sampling;therefore,the stress tensors were obtained by searching for the optimal solution using the least squares criterion based on the Monte Carlo ***,we constrained the stress tensor based on the tensile strength criterion,compressive strength criterion,and vertical stress *** inverted stress tensors were presented and analyzed based on the tensorial nature of the stress using the Euclidean mean stress *** stress-measurement campaigns in Weifang(Shandong Province,China)and Mercantour road tunnel(France)were implemented to highlight the validity and efficiency of the modified HTPF(M-HTPF)*** results showed that the M-HTPF method can be applied for stress tensor inversion using only three to four tests on pre-existing fractures,neglecting the stress *** inversion results were confined to relatively small distribution dispersions and were significantly reliable and stable due to the shear stresses on the fractures and the stress constraints *** M-HTPF method is highly feasible and efficient for complete stress tensor determination in a single borehole.

关键词： Stress tensor Hydraulic tests on pre-existing fractures Mean stress Stress constraint Hydraulic fracturing

Thermal and mechanical behavior of casting copper alloy wheel during wheel and belt continuous casting process

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China Foundry 2024年第1期21卷 82-90页

作者： Kun gao Yan Peng School of Mechanical Engineering Yanshan UniversityQinhuangdao 066004HebeiChina

To investigate the thermal and mechanical behavior of casting wheel,a two-dimensional thermoelastic-plastic finite element model was used to predict the temperature,stress and distortion distribution of the casting wheel during the wheel and belt continuous casting *** effects of grinding thickness and casting speed on the thermal and mechanical behaviors of the center of the hot face of the casting wheel were discussed in *** each rotation,the casting wheel passes through four different spray *** results show that the temperature distribution of the casting wheel in different spray zones is similar,the temperature of the hot face is the highest and the temperature reaches the peak in the spray zoneⅢ.The stress and distortion depend on the temperature distribution,and the maximum stress and distortion of the hot face are 358.2 MPa and 1.82 mm,*** temperature at the center of the hot face decreases with increasing grinding thickness and increases with increasing casting speed.

关键词： casting wheel finite element model grinding thickness casting speed hot face spray zones