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Double [5]carbohelicene: facile synthesis, chiroptical properties,isomerization study, and lasing application

Science China Chemistry 2025年第1期 233-240页

作者： Peipei Liu yantong Li Meng-Xiang Wu Hao Kang Xiao-Li zhao Lin Xu Linlin Liu Xiaodong Li Junfeng Fang Zhiwei Fang ya Cheng Hai-Bo yang Huakang Yu Xueliang Shi State Key Laboratory of Petroleum Molecular & Process Engineering Shanghai Key Laboratory of Green Chemistry and Chemical ProcessesSchool of Chemistry and Molecular Engineering East China Normal University School of Physics and Optoelectronics South China University of Technology Institute of Polymer Optoelectronic Materials & Devices State Key Laboratory of Luminescent Materials & Devices South China University of Technology School of Physics and Electronic Science Engineering Research Center of Nanophotonics & Advanced Instrument Ministry of EducationEast China Normal University State Key Laboratory of Precision Spectroscopy School of Physics and Electronic Science East China Normal University

Double carbohelicenes have attracted considerable attention due to their aesthetic structures, distinct π-conjugation extension, inherent chirality, and intriguing optical and electronic properties. Herein, the concise de novo synthesis of a new double[5]carbohelicene 1 together with its chiroptical properties, isomerization process and lasing application is presented. 1 was synthesized by a simple protocol involving the formation of a 6,6′-bipentacene as the key intermediate. It is worth noting that1 existed as two diastereomers 1-PP/MM and 1-PM, which were successfully isolated and unambiguously confirmed by Xray crystallography. The optical resolution of the racemic 1-PP/MM was successfully achieved by chiral-phase highperformance liquid chromatography（HPLC）, and 1-PP and 1-MM were characterized by circular dichroism. Interestingly, it was found that 1-PP/MM could be completely isomerized to 1-PM upon heating, and the detailed thermodynamics and kinetics of the isomerization process were systematically investigated. 1-PM exhibited deep-red luminescence with emission maximum at 723 nm and fluorescence quantum yield as high as 32.95%. Consequently, we can showcase the lasing application of 1-PM by doping with epoxy resin to assemble a bottle microlaser spontaneously, which the lasing wavelength is 796.6 nm at a threshold of 0.8 m J cm-2. We believe that our studies, including the facile synthesis methodology, detailed isomerization studies, and lasing application, will shed some light on the design and synthesis of novel carbohelical systems with more functions.

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Nuclear dynamics in multinucleon transfer reactions near Coulomb barrier energies

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Nuclear Science and Techniques 2018年第12期29卷 128-133页

作者： Peng-Hui Chen fei Niu ya-fei Guo zhao-Qing Feng Institute of Modern Physics Chinese Academy of SciencesLanzhou 730000 China University of Chinese Academy of Sciences Beijing 100190China South China University of Technology Guangzhou 510641China

The mechanism of multinucleon transfer reactions has been investigated within the dinuclear system model, in which the sequential nucleon transfer is described by solving a set of microscopically derived master equations. The transfer dynamics in the reaction of^(136)Xe+^(208)Pb near Coulomb barrier energies is thoroughly analyzed. It is found that the total kinetic energies of primary fragments are dissipated from the relative motion energy of two touching nuclei and exhibit a symmetric distribution along the fragment mass. The angular distribution of the projectile-like fragments moves forward with increasing beam energy. However, the target-like fragments exhibit an opposite trend. The shell effect is pronounced due to the fragment yields in multinucleon transfer reactions.

关键词：原子动力学转移反应精力库仑相对运动显微镜子转移原子核

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Mechanism of high temperature reduction on iron carbide preparation with low-grade siderite

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Journal of Iron and Steel Research International 2022年第9期29卷 1357-1367页

作者： Dong Chen ya-nan Lv Wei zhao fei-bao Wu Wei-ang Ying School of Iron and Steel Soochow UniversitySuzhou 215021JiangsuChina Department of Mechanical and Electrical Engineering Suzhou Institute of Industrial TechnologySuzhou 215104JiangsuChina

The carburization roasting followed by magnetic separation is a feasible method to utilize low-grade siderite *** order to enhance the carburization efficiency and separation effciency,high temperature reduction was carried out,and its mechanism was demonstrated by measuring carburization index,phase change,and microstructure under a carbon-sulfur infrared analyzer,an X-ray diffractometer,and a metallurgical *** results show that both the carburization effciency of siderite pellet and the separation efficiency of iron carbide from gangue are very ***,high temperature reduction is a useful way to enhance the carburization efficiency,as it can accelerate the reduction reaction rate and carburization reaction ***,high temperature reduction can improve the growth of iron carbide particle,promote the carburization efficiency,and strengthen the sodium modification reactions,thereby greatly accelerating the separation efficiency of iron carbide and *** the siderite pellets were reduced at 1050℃ for 90 min and carburized at 650℃ for 120 min,the carburization index of carburized pellets reached *** magnetic separation treatment,an electric furnace burden assaying 83.12 wt.%Fe and 6.96 wt.%C was prepared,and the corresponding iron recovery rate was 95.43%.The high temperature reduction is promisingly adopted to promote the utilization of low-grade siderite ores using carburization-magnetic separation technology.

关键词： Siderite High temperature reduction Carburization-Separation Iron carbide

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Income inequality and growth from functional orientation and spatial policy:Case study of Tibet,China

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Journal of Mountain Science 2021年第1期18卷 178-193页

作者： zhao yan-nan FAN Jie WANG ya-fei LIANG Bo ZHANG Lu Institute of Geographic Sciences and Natural Resources Research Chinese Academy of SciencesChaoyang DistrictBeijing 100101China University of Chinese Academy of Sciences Beijing 100049China Beijing Technology and Business University School of International Economics and ManagementBeijing 100048China

Economic inequality and poverty are *** attention has been paid to these issues in recent *** on economic inequality have been characterized by geographical disparities and a lack of consideration of functional *** one of the most typical and featured mountainous areas in Western China,Tibet demonstrates both the necessity and urgency of conducting studies on income inequality and growth *** paper proposes to address these problems by exploring the temporal and geographical variations in income inequality in Tibet,thereby revealing the differences in functional *** Markov chains and panel regression analysis were applied to identify the spatial-temporal dynamics of income *** results of this study show that(1)the overall income inequality in Tibet shows an expanding trend in the period 2005–2010 and a converging trend in the period 2010–2015,and there is a large disparity in income inequality between functional zones;(2)Tibetan farmers and herdsmen may face great difficulties in achieving substantial growth in the near future;(3)frontier counties,cultivated land,and grassland areas have negative impacts on income growth,while cordyceps counties,GDP per capita,agricultural product proportion,transfer payments,the ratio of nonagricultural employment to the total employment,the length of the average schooling year,and the slaughter rate of cattle and sheep have positive impacts;and(4)functional orientation has made great differences to income inequality and its *** light of these results,evidence-based policies have been formulated to boost average household income and narrow income inequality in Tibet.

关键词： Income inequality Markov chains Mechanism Functionalorientation Transfer payment Tibet China

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Variant selection of nanocrystalline a phase in metastableβTB8 titanium alloy via electric pulse treatment

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Rare Metals 2023年第8期42卷 2781-2794页

作者： Shan-Shan Wu ya yang Yuan-Biao Tan Song Xiang ya-Li Zhou Min Ma fei zhao Wei Shi Guizhou Key Laboratory of Materials Mechanical Behavior and Microstructure College of Materials and MetallurgyGuizhou UniversityGuiyang 550025China College of Materials Science and Engineering Hunan University of Science and TechnologyXiangtan 411201China

In this paper,the metastableβTB8 titanium alloy with nanocrystallineαphase is achieved by electric pulse *** morphology evolution and variant selection of nanocrystallineαphase in metastableβTB8titanium alloy were investigated by using scanning electron microscope(SEM),electron backscattered diffraction(EBSD)and transmission electron microscope(TEM)*** results indicated that the morphologies of the nanocrystallineαphase were mainly triangular clusters and needle-like at the pressure of 0 *** increasing pressure from 20 to 50 MPa,the volume fraction of needlelikeαphase decreased,and a large amount of V-shapedαphase formed in the interior ofβ*** on the EBSD data,the parentβphase was reconstructed by MTEX *** the interior of theβgrains,12 variants can form for the samples electric pulse treated at 0 and20 MPa,while only 3 and 6 variants can form for the samples electric pulse treated at 30 and 50 *** the grain boundary of theβgrains,one or more grain boundaryαvariants can be generated for the samples electric pulse treated at different pressures as long as one of the neighborβgrains follows the Burgers orientation relationship.

关键词： TB8 titanium alloy Parentβgrain reconstruction Morphology ofαphase Variant selection

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Establishment and verification of theoretical model for underwater light-sheet Scheimpflug LiDAR system

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Science China Technological Sciences 2025年第1期 54-61页

作者： fei FENG Guojun WU Bo LIU Xu zhao yafeng WU Jinghan XU Xi'an Institute of Optics and Precision Mechanics Chinese Academy of Sciences University of Chinese Academy of Sciences

The Scheimpflug imaging in the air can increase the depth-of-view and has been well studied with an accurate Scheimpflug imaging model. However, there is no corresponding underwater light-sheet Scheimpflug(ULSS) imaging *** a result, imaging accuracy cannot be ensured in the design phase, which mainly relies on the post-calibration. In this paper,the ULSS imaging model is firstly established, which gives the relationship between the pixel number and target distance, as well as that between the target distance and range resolution. A new experimental bracket and an underwater Scheimflug imaging lens were designed and developed. Based on this new device, several experiments were carried out in a pool to study the range resolution of this ULSS LiDAR, by which the correctness of the imaging model was verified. It also shows that the newly designed ULSS LiDAR can achieve a millimeter-level resolution within 8 m.

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Preparation of Titanium-silphenylene-siloxane Hybrid Polymers with High Refractive Index,Transmittance,and Thermal Stability

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Chinese Journal of Polymer Science 2020年第9期38卷 973-982,I0007页

作者： Dong zhao Shu-Xi Shan Meng Zhang Xiao-A Zhang Sheng-Ling Jiang ya-fei Lyu Key Laboratory of Carbon Fiber and Functional Polymers of Ministry of Education College of Materials Science and EngineeringBeijing University of Chemical TechnologyBeijing 100029China

Vinyl-containingtitanium-silphenylene-sioxane oligomers(O1,O2,O3,andO4)withdifferent molar ratios of titanium to silicon were successfully synthesized in high yields by nonhydrolytic sol-gel reaction,and the obtained four oligomers were further crosslinked with methylphenyl hydro-silicone oil(4)to form corresponding polymers(P1,P2,P3,and P4)by hydrosilylation *** structures were characterized with spectroscopic characterization techniques including FTIR,1H-NMR,and Raman *** effect of titanium element on crosslinking behavior,thermal resistance,refractive index,transparency,thermal aging stability,glass transition temperature,and surface properties of the polymers were *** with titanium-free polymer P1,the thermal resistance,refractive index,and thermal aging stability of titanium-silphenylene-siloxane polymers(P2,P3,and P4)were significantly *** titanium-silphenylene-siloxane polymers achieved a high refractive index(n=1.580-1.584)and thermostability(Tsd>500℃).In thermal aging,the polymers exhibited superior performances with high optical transparency(~90%at 450 nm)and exhibited high thermal stability(~84%at 450 nm after thermal aging at 150℃for 120 h).These data indicate that the polymers have potential application in optical materials such as LED encapsulants.

关键词： Titanium-silphenylene-siloxane hybrid polymers High refractive index and transmittance Thermal stability

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Using highly concentrated chloride solutions to leach valuable metals from cathode-active materials in spent lithium-ion batteries

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Rare Metals 2021年第7期40卷 1971-1978页

作者： Ai-fei Yi zhao-Wu Zhu ya-Hui Liu Jian Zhang Hui Su Tao Qi National Engineering Laboratory for Hydrometallurgical Cleaner Production Technology Institute of Process EngineeringChinese Academy of SciencesBeijing 100190China Key Laboratory of Green Process and Engineering Institute of Process EngineeringChinese Academy of SciencesBeijing 100190China School of Chemistry and Chemical Engineering University of Chinese Academy of SciencesBeijing 101407China

This study focused on the extraction of valuable metals from the cathode-active materials in spent lithiumion batteries using a high-concentration chloride *** effects of the concentrations of ammonium chloride(NH4 Cl),hydrochloric acid(HCl),and reductants such as hydrogen peroxide(H_(2)O_(2))and urea(CO(NH_(2))_(2))on metal extraction and chlorine production were studied *** leaching mechanism was analyzed,and a leaching model was *** was found that the addition of solid NH4 Cl to an HCl solution significantly improved the metal extraction capability of the latter and reduced the formation of chlorine gas by 96.0%compared to that only using *** activation energies for leaching Li,Ni,Co,and Mn were determined to be 30.4,38.5,30.6,and 38.2 kJ·mol^(-1),*** study demonstrates an environmentally friendly method for recycling metal resources from cathode-active materials and furthers understanding of how NH4 Cl inhibits chlorine production when leaching with mixed solutions of HCl and NH4 Cl.

关键词： Lithium-ion batteries Hydrochloric acid Ammonium chloride Chlorine gas

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某航空发动机金属密封环优化设计研究

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风机技术 2022年第3期64卷 38-43页

作者：赵亚飞潘晨爽杨滢滢励行根李征中国航发四川燃气涡轮研究院山东大学材料学院上海理工大学宁波天生密封件有限公司

为了满足特殊工况下发动机中的密封要求,对W形金属密封环综合性能进行研究。对W形金属密封环进行参数化建模,采用数值模拟正交试验法,应用ANSYS软件进行W形密封环的密封性能的分析计算,根据多指标数值模拟正交仿真试验计算结果,运用MAT... 详细信息

为了满足特殊工况下发动机中的密封要求,对W形金属密封环综合性能进行研究。对W形金属密封环进行参数化建模,采用数值模拟正交试验法,应用ANSYS软件进行W形密封环的密封性能的分析计算,根据多指标数值模拟正交仿真试验计算结果,运用MATLAB软件建立W形金属密封环关于其主要结构参数的多元线性回归方程。为保证其密封性能,应求得在最大Von-Mises等效应力不超过材料屈服极限条件下,寻找接触应力的最大值。通过C语言程序设计在其各结构参数限定范围内求解其极值,并得到极值对应的结构参数;对优化后的结构进行ANSYS模拟,并对结果进行检验,从而证明了优化设计的可靠性。

关键词： W形金属密封环参数化模型接触应力密封性能优化设计

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Isospin effect in peripheral heavy-ion collisions at Fermi energies

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Chinese Physics C 2018年第12期42卷 132-139页

作者： ya-fei Guo Peng-Hui Chen fei Niu zhao-Qing Feng Institute of Modern Physics Chinese Academy of SciencesLanzhou 730000China University of Chinese Academy of Sciences Beijing 100190China School of Physics and Optoelectronics South China University of TechnologyGuangzhou 510640China

The isospin effect in peripheral heavy-ion collisions was thoroughly investigated within the framework of the Lanzhou quantum molecular dynamics （LQMD） transport model. A coalescence approach was used to recognize the primary fragments formed in nucleus-nucleus collisions. described using the statistical code GEMINI. The production The secondary decay process of these fragments was mechanism and isospin effect of the projectile-like and target-like fragments were analyzed using the combined approach. It was found that the isospin migration from the high-isospin density to the low-density matter occurred in the neutron-rich nuclear reactions, i.e., ^48Ca＋^208Pb, ^86Kr＋^48SCa/^208Pb/^124Sn,^136Xe＋^208Pb, ^124Sn＋^124Sn, and ^136Xe＋^136Xe. A hard symmetry energy was available for creating the neutron-rich fragments, particularly in the medium-mass region. The isospin effect of the neutron-to- proton （n/p） ratio of the complex fragments was reduced when the secondary decay process was included. However, a soft symmetry energy enhanced the n/p ratio of the light particles, particularly at kinetic energies greater than 15 MeV/nucleon.

关键词： symmetry energy nuclear fragmentation reaction neutron-rich nuclei LQMD transport model

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