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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

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

Durable poly(binaphthyl-co-p-terphenyl piperidinium)-based anion exchange membranes with dual side chains

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Journal of Energy Chemistry 2024年第2期89卷 324-335,I0008页

作者： Weiting gao Xuelang gao Qiugen Zhang Aimei Zhu Qinglin Liu Department of Chemical&Biochemical Engineering Fujian Provincial Key Laboratory of Theoretical and Computational ChemistryThe College of Chemistry and Chemical EngineeringXiamen UniversityXiamen 361005FujianChina Department of Chemistry Pohang University of Science and Technology(POSTECH)Pohang 790-784South Korea

Building well-developed ion-conductive highways is highly desirable for anion exchange membranes(AEMs).Grafting side chain is a highly effective approach for constructing a well-defined phaseseparated morphological structure and forming unblocked ion pathways in AEMs for fast ion *** of side chains can further enhance phase separation due to the superhydrophobic nature of fluorine ***,their electronic effect on the alkaline stability of side chains and membranes is rarely ***,fluorine-containing and fluorine-free side chains are introduced into the polyaromatic backbone in proper configuration to investigate the impact of the fluorine terminal group on the stability of the side chains and membrane *** poly(binaphthyl-co-p-terphenyl piperidinium)AEM(QBNp TP)has the highest molecular weight and most dimensional stability due to its favorable backbone arrangement among ortho-and meta-terphenyl based ***,by introducing both a fluorinated piperidinium side chain and a hexane chain into the p-terphenyl-based backbone,the prepared AEM(QBNp TP-QFC)presents an enhanced conductivity(150.6 m S cm^(-1))and a constrained swelling at 80℃.The electronic effect of fluorinated side chains is contemplated by experiments and *** results demonstrate that the presence of strong electro-withdrawing fluorine groups weakens the electronic cloud of adjacent C atoms,increasing OH^(-)attack on the C atom and improving the stability of piperidinium *** QBNp TP-QFC possesses a robust alkaline stability at 80℃(95.3%conductivity retention after testing in 2 M Na OH for 2160 h).An excellent peak power density of 1.44 W cm^(-2)and a remarkable durability at 80℃(4.5%voltage loss after 100 h)can be observed.

关键词： Anion exchange membranes Backbone structure Fluorinated side chain Alkaline stability

On the core entropy of Newton maps

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Science China Mathematics 2024年第1期67卷 77-128页

作者： Yan gao Department of Mathematics Shenzhen UniversityShenzhen 518060China

In this paper,we define the core entropy for postcritically-finite Newton maps and study its continuity within this *** show that the entropy function is not continuous in this family,which is different from the polyn... 详细信息

关键词： core entropy extended Newton graph critical marking polynomial Newton map

Segmental nature of the Red River fault revealed by seismic anisotropy and geological structures

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Science China Earth Sciences 2024年第8期67卷 2423-2443页

作者： Ying LI Yuan gao School of Earth and Space Sciences University of Science and Technology of ChinaHefei 230026China Key Laboratory of Earthquake Prediction Institute of Earthquake ForecastingChina Earthquake AdministrationBeijing 100036China

As the western boundary of the Sichuan-Yunnan block(SYB),the Red River fault(RRF)is a major fault that controls deep crustal movement and deformation in the southeast margin of the Tibetan Plateau and regulates middle-lower crustal *** data suggest that the RRF is segmented and exhibits distinct variations in seismicity,velocity structure and crustal deformation from north to *** anisotropy reveals a complex pattern of lateral spatial and vertical stratified distributions.(1)From the perspective of crustal stratification,in the upper crust,the fast wave polarization in the north segment of the RRF is complex and possibly influenced by the Sanjiang lateral collision zone and adjacent faults with varying *** fast wave polarization in the middle segment is in the NW-SE direction,indicating a localized area of closed down or locked up with consistent *** in the south segment,it presents a disordered pattern,signifying complex deep tectonics and stress conditions at the wedged intersection *** the middle-lower crust in the north and south segments of the RRF,the azimuthal anisotropy is strong and consistent with the spatial strike of the weak zone characterized by low-velocity and *** suggests a connection between the anisotropy and the material migration.(2)In the whole crustal scale,the fast wave directions in two sides of the RRF are consistent with the NW-SE tectonic *** indicates that the RRF,as a large fault potentially cutting through the whole crust,strongly controls the surrounding media.(3)In the lithospheric scale,the fast wave polarizations are oriented nearly E-W and independent of the fault strike,consistent with the low P-and S-wave velocity structures and positive radial anisotropy in the upper *** fast wave directions could be related to lithospheric olivine deformation and asthenospheric *** paper suggests a decoupling of deformation between the crust and the lithospheri

关键词： Red River fault Seismic anisotropy Geological structures Lithosphere Fault segmentation

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 BiologyLink?ping University

Light-emitting diodes(LEDs) have revolutionized the lighting and displays due to their superior energy efficiency. The 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.

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Effect of mesopore spatial distribution of HZSM-5 catalyst on zinc state and product distribution in 1-hexene aromatization

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Chinese Journal of Chemical Engineering 2024年第3期67卷 16-26页

作者： Chenhao Wei Di gao Guohao Zhang Liang Zhao Jinsen gao Chunming Xu The State Key Lab of Heavy Oil Processing China University of Petroleum(Beijing)Beijing 102249China SINOPEC Research Institute of Petroleum Processing Co. Ltd.Beijing 100083China

1-hexene aromatization is a promising technology to convert excess olefin in fluid catalytic cracking(FCC)gasoline to high-value benzene(B),toluene(T),and ***,the increasing market demand of xylene has put forward higher requirements for new generation of *** increasing xylene yield in 1-hexene aromatization,the effect of mesopore structure and spatial distribution on product distribution and Zn loading was *** with different mesopore spatial distribution were prepared by post-treatment of parent HZSM-5 zeolite,including NaOH treatment,tetra-propylammonium hydroxide(TPAOH)treatment,and *** was found the evenly distributed mesopore mainly prolongs the catalyst lifetime by enhancing diffusion properties but reduces the aromatics selectivity,as a result of damage of micropores close to the catalyst *** the selectivity of high-value xylene can be highly promoted when the mesopore is mainly distributed interior the ***,the state of loaded Zn was also affected by mesopores spatial *** the optimized catalyst,the xylene selectivity was enhanced by 12.4%compared with conventional Zn-loaded parent HZSM-5 catalyst at conversion over 99%.It was attributed to the synergy effect of mesopores spatial distribution and optimized acid *** work reveals the role of mesopores in different spatial positions of 1-hexene aromatization catalysts in the reaction process and the influence on metal distribution,as well as their synergistic effect two on the improvement of xylene selectivity,which can improve our understanding of catalyst pore structure and be helpful for the rational design of high-efficient catalyst.

关键词： 1-Hexene aromatization Alkali treatment Xylene selectivity Mesopores Zinc state