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Graphene-anchored sodium single atoms:A highly active and stable catalyst for transesterification reaction

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Nano Research 2024年第6期17卷 4979-4985页

作者： Song-Song Peng Yao Nian xing-Ru Song Xiang-Bin Shao Chen Gu Zhi-Wei xing Shi-Chao Qi Peng Tan You han Xiao-Qin Liu Lin-Bing Sun State Key Laboratory of Materials-Oriented Chemical Engineering Jiangsu National Synergetic Innovation Center for Advanced Materials(SICAM)College of Chemical EngineeringNanjing Tech University30 South Puzhu RoadNanjing 211816China School of Chemical Engineering and Technology Tianjin UniversityTianjin 300072China Haihe Laboratory of Sustainable Chemical Transformations Tianjin 300192China

Solid strong base catalysts have received considerable attention in various organic reactions due to their facile separation,neglectable corrosion,and environmental *** great progress has been made in the preparation of solid strong base catalysts,it is still challenging to avoid basic sites aggregation on support and active sites loss in reaction ***,we report a tandem redox strategy to prepare Na single atoms on graphene,producing a new kind of solid strong base catalyst(Na1/G).The base precursor NaNO_(3)was first reduced to Na2O by graphene(400℃)and successively to single atoms Na anchored on the graphene vacancies(800℃).Owing to the atomically dispersed of basicity,the resultant catalyst presents high activity toward the transesterification of methanol and ethylene carbonate to synthesize dimethyl carbonate(turnover frequency(TOF)value:125.7 h^(−1)),which is much better than the conventional counterpart Na2O/G and various reported solid strong bases(TOF:1.0-90.1 h^(−1)).Furthermore,thanks to the basicity anchored on graphene,the Na1/G catalyst shows excellent durability during *** work may provide a new direction for the development of solid strong base catalysts.

关键词： solid strong base catalyst basic sites redox graphene single Na atoms

Jetting of a near-wall cavitation bubble induced by another tandem bubble

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Journal of Hydrodynamics 2024年第3期36卷 444-456页

作者： Hui han Jing-zhu Wang Jian-lin Huang Peng-bo Bai Yong-gang Chen Yi-wei Wang Key Laboratory for Mechanics in Fluid Solid Coupling Systems Institute of MechanicsChinese Academy of SciencesBeijing100190China School of Engineering Science University of Chinese Academy of SciencesBeijing100049China Guangdong Aerospace Research Academy Guangzhou511458China School of Future Technology University of Chinese Academy of SciencesBeijing100049China Jianghuai Advance Technology Center Hefei230088China

Double bubbles near a rigid wall surface collapse to produce a significant jet impact,with potential applications in surface cleaning and ultrasonic ***,the dynamic behaviors of near-wall bubbles remain *** this study,we investigate the jetting of a near-wall bubble induced by another tandem *** define two dimensionless standoff distances,γ_(1),γ_(2),to represent the distances from the center of the near-wall bubble to the rigid wall and the center of controlling bubble to the center of the near-wall bubble,*** observations reveal three distinct jetting regimes for the near-wall bubble:transferred jetting,double jetting,and directed *** further investigate the jetting mechanism,numerical simulations are conducted using the compressibleInterFoam solver in the open-source framework of OpenFOAM.A detailed analysis shows that the transferred jet flow is caused by the pinch-off resulting from the axial contraction velocity at the lower end of the near-wall bubble being greater than the vertical contraction velocity,leading to a maximum jet velocity of 682.58 m/*** the case of double jetting,intense stretching between the controlling bubble and the wall leads to a pinch-off and a double jetting with a maximum velocity of 1096.29 m/*** directed jet flow is caused by the downward movement of the high-pressure region generated by the premature collapse of the controlling bubble,with the maximum jet velocity reaching 444.62 m/s.

关键词： Jetting of near-wall bubble controlling bubble impact velocity

Pollutant emissions from biomass burning:A review on emission characteristics,environmental impacts,and research perspectives

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Particuology 2024年第2期85卷 296-309页

作者： Ke Jiang Ran xing Zhihan Luo Wenxuan Huang Fan Yi Yatai Men Nan Zhao Zhaofeng Chang jinfeng Zhao bo Pan Guofeng shen College of Urban and Environmental Sciences Peking UniversityBeijing100871China Beijing Key Lab Plant Resources Research and Development Beijing Technology and Business UniversityBeijing100048China College of Ecology and Environment Zhengzhou UniversityZhengzhou450001China Facultyof Environmental Sciences and Engineering Kunming University of Science and TechnologyYunnan Provincial Key Laboratoryof Soil Carbon Sequestration and Pollution ControlKunming650500China Institute of Carbon Neutrality Peking UniversityBeijing100871China

Biomass is one most abundant resource on the earth providing important energies in support of so-cioeconomic development in many *** of biomass fuels comprises to nearly 10%of the total energy from anthropogenic combustion processes:however,as the burning is usually incomplete,this process yields products of incomplete combustion posing consequently significant impacts on air quality,human health,and climate ***,we analyzed spatiotemporal characteristics in intentional and unintentional biomass burning from different sectors,discussed impacts of biomass burning emissions on indoor and outdoor air quality,and consequent influences on human *** global total con-sumption amount of biomass including both natural and anthropogenic sources was approximately 7900 Tg in 2019,with significantly large regional and sectorial discrepancies among ***,anthropogenic biomass burning amounts increased gradually,but notably in some developing countries like China residential consumption of biomass fuels,as one large sector of biomass use,decreased over *** biomass consumption needs to be accurately *** are relatively rich datasets of pollutant emission factors from biomass burning,including laboratory and field tests,but still large variations exit and contribute substantially to the uncertainty in emission *** pri-mary PM2.5,black carbon and organic carbon emissions from biomass burning were about 51,4.6,and 29 Tg,respectively,contributing to nearly 70%,55%,and 90%of the total emission from all sources,and emissions from the residential sector and open fires are major *** carbon emissions from biomass burning attracts growing interests but available studies adopted different methodologies challenging the comparability of those *** burning emissions polluted not only ambient air but more severely indoor air quality,adversely affecting human *** studies that should be emphasiz

关键词： Biomass burning Carbonaceous aerosol Emission Air quality Human health

Multiple factors influencing high-purity indium electrolytic refining

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Chinese Journal of Chemical Engineering 2024年第7期71卷 148-160页

作者： Hong-Qiang Fan Fei Li Hong-xing Zheng Wu-ji Pan Mei-Zhen Wu Yashar Behnamian Ju-bo Peng Dong-Hai Lin State Key Laboratory of Advanced Special Steel&School of Materials Science and Engineering Shanghai UniversityShanghai 200444China Shanghai Engineering Research Center for Integrated Circuits and Advanced Display Materials Shanghai UniversityShanghai 200444China Research&Development Center Yunnan Tin Group(Holding)Limited CompanyKunming 650032China Department of Chemical and Materials Engineering University of AlbertaEdmonton T6G 2V4AlbertaCanada School of Energy and Materials Shanghai Key Laboratory of Engineering Materials Application and EvaluationShanghai Polytechnic UniversityShanghai 201209China

The effects of various contaminants in the electrolytic refinement of indium were investigated using a glow discharge mass spectrometer(GDMS).The effects of several factors such as the indium ion(In3+)concentration,the sodium chloride(NaCl)concentration,the current density,the gelatin concentration,the pH,and the electrode distance,were *** variations in impurity levels concerning gelatin concentration were *** the gelatin and In3+concentration were moderately positively correlated with the Pb *** Sb concentration was associated positively with the NaCl concentration,while the Ti concentration had an adverse correlation with the NaCl *** Bi element content was positively linked to the electrode *** the current density increased,Cu,Pb,and Bi impurities initially rose and then eventually ***,a critical current density of 45 A·m^(-2) was identified in this behavior.

关键词： High-purity indium Electrolysis Multiple factors Electrochemistry Purification

Non-flammable long chain phosphate ester based electrolyte via competitive solventized structures for high-performance lithium metal batteries

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Journal of Energy Chemistry 2024年第10期97卷 156-165页

作者： Li Liao Zhiqiang han Xuanjie Feng Pan Luo Jialin Song Yin Shen Xiaoshuang Luo Xinpeng Li Xuanzhong Wen bo Yu Junchen Chen Bingshu Guo Mingshan Wang Yun Huang Hongmei Zhang Mengmeng Yin Jiangtao Liu Yuanhua Lin xing Li School of New Energy and Materials Southwest Petroleum University Beijing Advanced Innovation Center for Materials Genome Engineering Center for Green Innovation School of Mathematics and Physics University of Science and Technology Beijing State Key Laboratory of Advanced Chemical Power Sources Guizhou Meiling Power Sources Co.Ltd

Safety remains a persistent challenge for high-energy-density lithium metal batteries（LMBs）.The development of safe and non-flammable electrolytes is especially important in harsh conditions such as high ***,a flame-retardant,low-cost and thermally stable long chain phosphate ester based（tributyl phosphate,TBP） electrolyte is reported,which can effectively enhance the cycling stability of highly loaded high-nickel LMBs with high safety through co-solvation *** interfacial compatibility between TBP and electrode is effectively improved using a short-chain ether（glycol dimethyl ether,DME）,and a specially competitive solvation structure is further constructed using lithium borate difluorooxalate（LiDFOB） to form the stable and inorganic-rich electrode *** from the presence of the cathode electrolyte interphase（CEI） and solid electrolyte interphase（SEI） enriched with LiF and LixPOyFz,the electrolyte demonstrates excellent cycling stability assembled using a 50 μm lithium foil anode in combination with a high loading NMC811(15.4 mg cm-2) cathode,with 88% capacity retention after 120 ***,the electrolyte exhibits excellent high-temperature characteristics when used in a 1-Ah pouch cell（N/P=0.26）,and higher thermal runaway temperature（238℃） in the ARC（accelerating rate calorimeter） demonstrating high *** novel electrolyte adopts long-chain phosphate as the main solvent for the first time,and would provide a new idea for the development of extremely high safety and high-temperature electrolytes.

关键词： Battery safety Lithium metal batteries Long chain phosphate ester Non-flammable electrolyte Solvation structure

Two new high-temperature molecular ferroelectrics[1,5-3.2.2-Hdabcn]X(X=ClO_(4)^(-),ReO_(4)^(-))

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Chinese Chemical Letters 2024年第6期35卷 234-238页

作者： Keke han Wenjun Rao Xiuli You Haina Zhang xing Ye Zhenhong Wei Hu Cai School of Chemistry and Chemical Engineering Nanchang UniversityNanchang 330031China Jiangxi Key laboratory of Organic Chemistry Jiangxi Science and Technology Normal UniversityNanchang 330013China

Molecular ferroelectrics have attracted much attention because of their excellent piezoelectricity,mechanical workability,and second harmonic ***,we successfully prepared two molecular ferroelectrics[1,5-3.2.2-Hdabcn]X(X=ClO_(4)^(-),1;ReO_(4)^(-),2)by reactions of a quasi-spherical amine 1,5-diazabicycle[3.2.2]nonane(1.5-3.2.2-dabcn)with HX aqueous *** 1 and 2 undergo hightemperature phase transitions at 381 K(1)and 396 K(2).Before and after the phase transition,they crystallize in the polar point group mm2,and the centrosymmetric point groups mmm and 4/mmm,*** to Aizu rules,these two compounds experience mmm Fmm2 and 4/mmm Fmm2 type ferroelectric phase transitions,*** ferroelectricity of both compounds is well expressed in their polycrystalline film at room temperature with low coercive voltages of 13 V for 1 and 25 V for *** piezoelectric force microscopy(PFM),the 180°anti-parallel ferroelectric domains and the reversible polarization switching can be clearly observed in 1 and *** high-temperature molecular ferroelectric material has great application potential in flexible materials,biomechanics,intelligent wearables and other fields.

关键词： Ferroelectric domains Quasi-spherical amine Phase transition Polarization

Prognostic value of a nomogram model for postoperative liver metastasis of colon cancer

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World Journal of Gastrointestinal Surgery 2024年第4期16卷 1055-1065页

作者： De-Xin Cheng Kang-Di Xu han-bo Liu Yi Liu Department of Interventional Medicine Zhejiang Provincial People’s Hospital(Affiliated People’s HospitalHangzhou Medical College)Hangzhou 310014Zhejiang ProvinceChina General Surgery Cancer CenterDepartment of Vascular SurgeryZhejiang Provincial People’s Hospital(Affiliated People’s HospitalHangzhou Medical College)Hangzhou 310014Zhejiang ProvinceChina

BACKGROUND Colon cancer is one of the most common malignant tumors of the digestive *** metastasis after colon cancer surgery is the primary cause of death in patients with colon *** To construct a novel nomogram model including various factors to predict liver metastasis after colon cancer *** We retrospectively analyzed 242 patients with colon cancer who were admitted and underwent radical resection for colon cancer in Zhejiang Provincial People’s Hospital from December 2019 to December *** were divided into liver metastasis and non-liver metastasis ***,age,and other general and clinicopathological data(preoperative blood routine and biochemical test indexes)were *** risk factors for liver metastasis were analyzed using singlefactor and multifactorial logistic regression.A predictive model was then constructed and evaluated for *** Systemic inflammatory index(SII),C-reactive protein/albumin ratio(CAR),red blood cell distribution width(RDW),alanine aminotransferase,preoperative carcinoembryonic antigen level,and lymphatic metastasis were different between groups(Phan those in extreme cases,indicating that the model is *** Liver metastases after colorectal cancer surgery could be well predicted by a nomogram based on the SII,CAR,and RDW.

关键词： Systemic immunoinflammatory index C-reactive protein/albumin ratio Erythrocyte distribution width Colon cancer Liver metastasis Novel nomogram model

Discovery and characterization of a new hydrothermal field at 2°N on the slow-spreading Carlsberg Ridge

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Journal of Oceanology and Limnology 2024年第4期42卷 1106-1118页

作者： Zhongyan QIU Yejian WANG Xiqiu han Honglin LI xing YU Ruyong CUI Mou LI Xuegang CHEN Jiqiang LIU Key Laboratory of Submarine Geosciences&Second Institute of Oceanography Ministry of Natural ResourcesHangzhou 310012China Qingdao Institute of Marine Geology China Geological SurveyQingdao 266071China School of Earth Science Zhejiang UniversityHangzhou 310027China Ocean College Zhejiang UniversityZhoushan 316021China

A new hydrothermal field(Tianshi)was discovered on the rift valley wall through plume anomaly surveys and geological work conducted in 2012 and 2018 between 2°35′N and 2°43′N of the slow-spreading Carlsberg Ridge(CR).Here,the results of two expeditions conducted to detect and characterize the new hydrothermal field are *** and geochemical data,as well as 14 C ages of a sediment core collected near the field are presented to reveal the hydrothermal *** show that the Tianshi field is a basalt-hosted hydrothermal *** data of the sediments collected near the field indicate a strong hydrothermal contribution,and hydrothermal Fe and Cu fluxes range from 30 to 155 mg/(cm^(2)·ka)and 0.59 to 11.49 mg/(cm^(2)·ka),*** variations in the fluxes of hydrothermal Fe indicate that there have been at least three amplified hydrothermal venting events(H 1,H 2,and H 3)in the Tianshi field over the last 35.2 ka,in 28.6-35.2 ka BP,22.0-27.6 ka BP,and 1.2-11.4 ka BP,*** event H 2 was driven by an increased magmatic production associated with sea level fall during the Last Glacial Maximum,while event H 3 was promoted by tectonic activity associated with a rapid sea level *** study further verified the role of sea level change in modulating hydrothermal activity on mid-ocean ridges.

关键词： plume anomaly sediment core new hydrothermal field hydrothermal history Carlsberg Ridge

Early-stage latent thermal failure of single-crystal Ni-rich layered cathode

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Journal of Energy Chemistry 2024年第9期96卷 578-587页

作者： Xiao han Ruoyu Xu Yan Li Yang Ding Manchen Zhang bo Wang Xiaoxing Ke Manling Sui Pengfei Yan Beijing Key Laboratory of Microstructure and Property of Solids Faculty of Materials and ManufacturingBeijing University of TechnologyBeijing 100124China Watt Laboratory Central Research InstituteHuawei Technologies Co.LTDShenzhen 518129GuangdongChina

High nickel content worsens the thermal stability of layered cathodes for lithium-ion batteries,raising safety concerns for their *** understanding the thermal failure process can offer valuable guidance for material optimization on thermal stability and new opportunities in monitoring battery thermal runaway(TR).Herein,this work comprehensively investigates the thermal failure process of a single-crystal nickel-rich layered cathode and finds that the latent thermal failure starts at∼120℃far below the TR temperature(225℃).During this stage of heat accumulation,sequential structure transition is revealed by atomic resolution electron microscopy,which follows the layered→cation mixing layered→LiMn_(2)O_(4)-type spinel→disordered spinel→rock *** progression occurs as a result of the continuous migration and densification of transition metal *** transition generates gaseous oxygen,initially confined within the isolated closed pores,thereby not showing any thermal failure phenomena at the *** temperature leads to pore growth and coalescence,and eventually to the formation of open pores,causing oxygen gas release and weight loss,which are the typical TR *** highlight that latent thermal instability occurs before the macro-level TR,suggesting that suppressing phase transitions caused by early thermal instability is a crucial direction for material *** findings can also be used for early warning of battery thermal runaway.

关键词： Thermal runaway Nickel-rich layered cathode Transmission electron microscopy Lithium-ion battery Phase transition