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Paleogene integrative stratigraphy and timescale of China

Science China Earth Sciences 2019年第1期62卷 287-309页

作者： Yuanqing WANG Qian LI Bin BAI Xun jin Fangyuan mao jin MENG Key Laboratory of Vertebrate Evolution and Human Origins of Chinese Academy of Sciences Institute of Vertebrate Paleontology and Paleoanthropology Chinese Academy of Sciences CAS Center for Excellence in Life and Paleoenvironment College of Earth Sciences University of Chinese Academy of Sciences American Museum of Natural History

The Paleogene is the first period after the Mesozoic Mass Extinction. Mammals become the dominant group in the terrestrial ecosystem with a rapid radiation, and Asia has been considered to be the origin place of several mammalian *** Paleogene System consists mostly of terrestrial deposits in Asia, especially in East Asia. A well-established regional chronostratigraphic framework is the foundation for understanding both the Paleogene geologic history and evolutionary history of Asia and their relationships. The Paleogene is subdivided into the Paleocene, Eocene and Oligocene in the International Chronostratigraphic Chart. Based on the land mammal ages, the Chinese terrestrial Paleogene can be subdivided into 11 stages:the Shanghuan, Nongshanian and Bayanulanian stages of the Paleocene, the Lingchan, Arshantan, Irdinmanhan, Sharamurunian,Ulangochuian and Baiyinian stages of the Eocene, and the Ulantatalian and Tabenbulukian stages of the Oligocene. These stages have distinctive paleontological characters, with special significance of fossil mammals, which provide a reliable practical *** bases of the Shanghuan, Lingchan, and Ulantatalian stages are coincident respectively with those of the Paleocene, Eocene and Oligocene. The ages for their bases are determined as 66.0, 56.0 and 33.9 Ma, respectively, following that for the corresponding series in the International Chronostratigraphic Chart. For other stages, estimated ages are provided based on available paleomagnetic results.

关键词： Paleogene Correlation Biostratigraphy Magnetostratigraphy Chronostratigraphy

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High transmittance and grain-orientated alumina ceramics fabricated by adding fine template particles

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Journal of Advanced Ceramics 2022年第4期11卷 582-588页

作者： Han chen jin ZHAO Shunzo SHIMAI Xiaojian mao Jian ZHANG Guohong ZHOU Shiwei WANG Na GU Kai ZHENG University of Chinese Academy of Sciences Beijing 100049China Center of Materials Science and Optoelectronics Engineering University of Chinese Academy of SciencesBeijing 100049China State Key Laboratory of High Performance Ceramics and Superfine Microstructure Shanghai Institute of CeramicsChinese Academy of SciencesShanghai 200050China Shandong Guiyuan Advanced Ceramics Co. Ltd.Zibo 255000China

Transparent Al_(2)O_(3) ceramics with grains aligned to the c-axis were prepared by adding platelets with a low aspect ratio into fine equiaxed *** mixed powders were formed into green bodies using spontaneous coagulation casting and sintered by pressureless sintering and hot-isostatic pressure *** potentials and rheological behavior of the slurries,relative densities of green bodies,and orientation and optical properties of sintered bodies were investigated and *** platelet with a high aspect ratio suppressed densification more seriously during sintering than the one with a low aspect *** excellent oriented structure was obtained when 5 wt%platelets with a low aspect ratio were added,and transparent Al_(2)O_(3) ceramics with grains aligned to c-axis were successfully prepared;the in-line transmittance was 78.4%at 600 nm,which is the highest one in the currently reported literature.

关键词： templated grain growth(TGG) orientation transparent alumina

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2023 HP special volume:Synergistic progress of high-pressure physics and chemistry

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Matter and Radiation at Extremes 2024年第6期9卷 1-3页

作者： Ho-Kwang mao Bin chen Huiyang Gou Kuo Li jin Liu Hong Xiao Wenge Yang Center for High Pressure Science and Technology Advanced Research 10 Xibeiwang East RoadHaidianBeijing 100094China Shanghai Key Laboratory MFree Shanghai Advanced Research in Physical SciencesPudongShanghai 201203China Yanshan University Qinhuangdao 066004China

New results presented in the 2023 MRE HP Special Volume clearly demonstrate the cross-disciplinary synergistic progress in high-pressure physics and *** prevalence of pressure-induced crystal chemistry of clathrate-like host-guest cages in borides,^(1,2)nitrides,^(3)and hydrides^(4)has led to exotic compositions and physical properties.

关键词： properties chemistry synergistic

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Enhanced electrochemical CO_(2)reduction coupled with urea oxidation using bifunctional atomically dispersed CuNi catalysts

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Nano Research 2025年第1期18卷 208-216页

作者： Wenjie Wu Haoyang Zhou Ying Liu Yifei Pan Qingqing chen Yu Zhang Junjie mao Wenjie Ma Ping Yu Beijing National Laboratory for Molecular Sciences Key Laboratory of Analytical Chemistry for Living BiosystemsInstitute of ChemistryChinese Academy of Sciences(CAS)Beijing 100190China College of Chemistry and Materials Science Anhui Normal UniversityWuhu 241002China University of Chinese Academy of Sciences Beijing 100049China

The electrochemical conversion of carbon dioxide(CO_(2))into chemical fuels represents a promising approach for addressing global carbon balance ***,this process is hindered by the kinetic limitations of anodic reactions,usually the oxygen evolution reaction,resulting in less efficient production of high value-added ***,we report an integrated electrocatalytic system that couples CO_(2)reduction reaction(CO_(2)RR)with urea oxidation reaction(UOR)using a bifunctional electrocatalyst with atomically dispersed dual-metal CuNi sites anchored on bamboo-like nitrogen-doped carbon nanotubes(CuNi-CNT),which were synthesized through a one-step pyrolysis *** bifunctional CuNi-CNT catalyst exhibits a near 100%CO Faraday efficiency for CO_(2)RR over a wide potential range and outstanding UOR performance with a negatively shifted potential of 210 mV at 10 mA·cm^(-2).In addition,we assemble a two-electrode electrolyzer using bifunctional CuNi-CNT-modified carbon fiber paper electrodes as both cathode and anode,capable of operating at a remarkably low cell voltage of 1.81 V at 10 mA·cm-2,significantly lower than conventional *** study provides a novel avenue to achieving an efficient carbon cycle with reduced electric power consumption.

关键词： electrochemical conversion bimetallic site catalyst bifunctional electrocatalyst carbon dioxide reduction urea oxidation

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Multidimensional hollow SiO_(2)/C nanofibers modified by magnetic nanocrystals for electromagnetic energy conversion and lithium battery storage

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Nano Research 2024年第8期17卷 7301-7314页

作者： chen Han Qi Zheng Juncheng jin Jiajia Zhang Wen-Qiang Cao Kun Xiang Min Zhang mao-Sheng Cao Anhui Provincial Laboratory of Biomimetic Sensor and Detecting Technology College of Materials and Chemical EngineeringWest Anhui UniversityLu’an 237012China School of Materials Science and Engineering Beijing Institute of TechnologyBeijing 100081China Department of Physics Beijing Technology and Business UniversityBeijing 100048China

Multifunctional materials are powerful tools to support the advancement of energy conversion *** with prominent electromagnetic and electrochemical properties can realize the conversion of electromagnetic energy and solve the subsequent storage ***,an electrospinning-thermal reduction method is employed to construct ultrafine nickel nanoparticle modified porous SiO_(2)/C(Ni-SiO_(2)/C)hollow nanofibers as promising materials for applications in both electromagnetic wave absorption(EMA)and lithium-ion ***,when used as an EMA material,the reflection loss(RL)of Ni-SiO_(2)/C can reach−47.8 dB at 15.8 GHz with a matching thickness of 2.2 *** excellent microwave absorption performance can be attributed to the enhanced conduction loss,polarization relaxation,synergistic magnetic loss,and preferred impedance matching,which result from multi-component magnetic/dielectric synergy and the unique interconnected multidimensional hollow ***,the electronic conductivity and electrochemical activity of the samples are significantly enhanced due to the uniform distribution of ultrafine Ni nanoparticles in the amorphous SiO_(2)/C ***,the hierarchical hollow porous structure provides sufficient free space for volume change during lithiation/delithiation ***,the Ni-SiO_(2)/C nanocomposite exhibits a high reversible capacity of 917.6 mAh·g^(−1)at 0.1 A·g^(−1).At a high current density of 2 A·g^(−1),a capacity of 563.9 mAh·g^(−1)can be maintained after 300 *** energy conversion-storage device is designed to store waste electromagnetic energy in the form of useful electrical *** work inspires the development of high-performance bifunctional materials.

关键词： Ni-SiO_(2)/C nanofiber electromagnetic absorption lithium-ion storage electrospinning multidimensional structure

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Twinning behavior of an extruded Mg-Gd-Y-Zn-Zr alloy sheet under tension and compression

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Journal of Rare Earths 2024年第12期42卷 2208-2216页

作者： Jianfen Huang Tao chen Wugui Jiang Longhui mao Zhiyong chen Key Laboratory for Microstructural Control of Metallic Materials of Jiangxi Province (Nanchang Hangkong University) School of Aeronautical Manufacturing Engineering Nanchang Hangkong University School of Materials Science and Engineering Central South University

In this study, twinning behaviors of an extruded Mg-4.7Gd-3.4Y-1.2Zn-0.5Zr(wt%) alloy sheet along different directions extrusion direction(ED), 45°: 45° to ED and transverse direction(TD) under tension and compression were investigated. The results show that:(i) the twinning frequency of the extruded alloy sheet along different directions shows obvious anisotropy under both tension and compression while demonstrating opposite orders of ED > 45°> TD under tension and TD > 45°> ED under compression. Such anisotropic twinning frequencies are both in accord with their average twinning Schmid factor(TSF) orders.(ii) Under both tension and compression, the twinning variants(TVs) with the highest and the second highest TSF are frequently selected with priority. However, the TV selection law under tension has a certain difference from that of compression, which should be related to the TSF distributions of ortho-TV, meta-TV and para-TV under tension and compression.

关键词： magnesium alloy texture twinning behavior anisotropy rare earths

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Luminescence of halophosphate solid-solution Ca5(PO4)3(F0.8Cl0.2)：Eu^2＋,Mn^2＋ for WLED

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Journal of Rare Earths 2018年第11期36卷 1157-1161页

作者： Jiashan mao Hongwei Fang Yonghu chen Department of Physics University of Science and Technology of China Hefei 230026 China The Science and Technology Department of Fujian Province Fuzhou 350003 China

Solid-solution based luminescent materials have been widely explored due to their tunable optical properties in recent years. In this work, instead of more common cation-substitution approach, we investigated the luminescence properties of Eu^2＋ and Mn^2 ＋ co-doped halophosphate solid solution Ca5（PO4）3（F0.8Cl0.2） via anion substitution synthesized by high temperature solid state reaction method. The formation of the solid solution was confirmed by X-ray diffraction （XRD） characterization, which indicates that the introduction of certain proportion of CI will not make significant change on the CaB（PO4）3F lattice, We also studied the energy transfer from Eu^2＋ to Mn^2＋ in the host so as to obtain white light emission via adjusting the doping concentrations of Eu^2＋ and Mn^2＋, The white light emission was achieved through combination of Eu^2＋ blue emission and Mn^2＋ red-orange emission with appropriate proportions. The results suggest that Ca5（PO4）3（F0.8Cl0.2）：0.01Eu^2＋＋,0.18Mn^2＋ could be a potential WLED phosphor working under ultraviolet excitation,

关键词： WLED Rare earth Transition metal Luminescence Energy transfer

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Challenges and Recent Developments of Photoflow-Reversible Deactivation Radical Polymerization(RDRP)

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Chinese Journal of Polymer Science 2021年第9期39卷 1069-1083页

作者： Zhuo-Ran Zhong Yi-Nan chen Yang Zhou mao chen State Key Laboratory of Molecular Engineering of Polymers Department of Macromolecular ScienceFudan UniversityShanghai 200433China

Photo-controlled reversible-deactivation radical polymerizati on(photo-RDRP)has been investigated as a"green"and spatiotem-porally controlling pathway for polymer *** the combination of photo-RDRP and flow chemistry has offered opportunities to increase light intensity and enable uniform light irradiation,problems associated with flow approaches still remain for photoflow-RDRP,which has hindered merging flow polymerization with other cutting-edge ***,we summarize challenges and recent achievements in photoflow-RDRP including the development of(a)droplet/slug-flow to regulate reside nee time distribution,(b)mixing techniques to tailor polymer,(c)polymerization in duced self-assembly,and(d)computer-aided *** hope this work will provide in formative knowledge to people in related fields and stimulate novel ideas to promote polymer synthesis in both academia and industry.

关键词： Controlled radical polymerization RDRP Photopolymerization Flow chemistry Flow polymerization

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Dispersity Regulation in Photo-controlled Radical Polymerization by Merging Aryl Sulfonyl Chloride Initiators and Mixed Disulfide Agents

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Chemical Research in Chinese Universities 2023年第5期39卷 816-821页

作者： ZHANG Lu ZHANG Zexi chen mao Department of Macromolecular Science State Key Laboratory of Molecular Engineering of PolymersFudan UniversityShanghai 200433P.R.China

On-demand regulation of molecular weight distribution(MWD)is crucial to influence the properties of *** this work,we reported an organocatalyzed photo-controlled radical polymerization(photo-CRP)from the tosyl chloride initiator by combining two disulfides as chain transfer *** novel synthetic protocol allows facile access toward well-defined polymers with tunable MWDs and predetermined molecular *** including structural characterization,kinetic investigation and chain-extension polymerization exhibited good chain-growth control for polymers of different *** the easy accessibility of the initiating site(sulfonyl chloride)on many aromatic sources,this work presents a promising avenue to modify such substances with polymers of tailored MWDs,chain lengths and repeating units under metal-free and mild conditions driven by light.

关键词： Reversible deactivation radical polymerization Photo-controlled radical polymerization Organocatalyst Molecular weight distribution Polymer chemistry

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On a Flexible Loan Repayment Method Depending on Borrower's Asset with an Early Termination Clause

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Acta Mathematicae Applicatae Sinica 2024年第2期40卷 557-567页

作者： jin LIANG Jia-qi mao Zhao-ya LIU School of Mathematical Sciences Tongji UniversityShanghai 200092China

Aiming at the problem that the asset’s fluctuation influences the borrower’s repayment ability,a loan with a new and flexible repayment method is designed,which depends on the asset value of the *** repayment method can reduce the loan default probability,but it causes the uncertainty of the pay off *** the repayment term is related to the regular repayment amount in this method,a boundary for the regular repayment amount is set up in order to avoid too long repayment *** will balance the benefit of borrowers and lenders and improve the applicability of this *** establishing a mathematical model of the residual value of the loan,this model can be transformed into an initial-boundary problem of a partial differential *** analytic solution and the expected time to pay off the loan are ***,numerical analysis are shown.

关键词： flexible repayment method repayment ratio early termination clause expected pay off time

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