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

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Science China Chemistry 2025年第1期 233-240页

作者： Peipei Liu ya.tong Li Meng-Xiang Wu Hao Kang Xiao-Li Zhao Lin Xu Linlin Liu Xiaodong Li Junfeng Fang Zhiwei Fang ya.Cheng Hai-bo ya.g 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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Structural engineering of high-entropy alloys for advanced electrocatalytic reactions

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Tungsten 2025年第1期 1-31页

作者： qiao Xie Ying-Jie Yu Hai-Jun Zhang ya.Ping Deng Wen Lei The State Key Laboratory of Refractories and Metallurgy Wuhan University of Science and Technology Department of Chemical Engineering Waterloo Institute for Sustainable Energy Waterloo Institute for Nanotechnology University of Waterloo

High-entropy alloys(HEAs) have emerged as promising candidates to replace traditional precious metal catalysts,owing to their unique chemical and physical *** review commences by revisiting the fundamental concepts of HEAs,including their synthesis methods and structural control strategies in *** underscores the critical role of meticulously manipulating both macroscopic and microscopic structures of the HEAs to optimize their catalytic performance.A deep understanding of the structure-activity relationship in HEAs across various configurations is pivotal in developing more effective *** review methodically encapsulates the research progress of structural control strategies for HEAs in achieving efficient energy conversion,with the aim of gaining a better understanding of the relationship between structure and *** review concludes by summarizing the current achievements and challenges,and suggestions for potential future directions of HEAs in the fields of energy conversion and environmental purification.

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Quantitative Research on Dissolving of Nb in High Nb Microalloyed Steels during Reheating

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Journal of Iron and Steel Research International 2014年第6期21卷 596-599页

作者： ya.bin CAO Fu-ren XIAO Gui-ying qiao bo LIAO School of Materials Science and Engineering Shijiazhuang Tiedao University Key Laboratory of Metastable Materials Science and Technology College of Materials Science and EngineeringYanshan University School of Environmental and Chemical Engineering Yanshan University

The accurate prediction of soluble Nb content during reheating is helpful for the design of chemical compo sition and reheating parameters for Nb-containing steels. The dissolution behavior of Nb in high Nb mieroailoyed steels was investigated. The results show that Nh does not entirely dissolve for high Nb microalloyed steels containing Ti after holding at 1 300 ℃ for 3 h. The soluble Nb content increases with the decrease of C content and/or the increase of Nb content in steels. Moreover, an expression has been established to describe the amount evolution of soluble Nb in high Nb microalloyed steels during reheating and the validity of this expression has also been verified by experiment.

关键词： quantitative research high Nb microalloyed steel dissolving soluble Nb modeling

Effect of Nb Solute and NbC Precipitates on Dynamic or Static Recrystallization in Nb Steels

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Journal of Iron and Steel Research International 2012年第11期19卷 52-56页

作者： XIAO Fu-ren CAO ya.bin qiao Gui-ying ZHANG Xiao-bing LIAO bo Key Laboratory of Metastable Materials Science and Technology College of Materials Science and EngineeringYanshan UniversityQinhuangdao 066004HebeiChina School of Environmental and Chemical Engineering Yanshan UniversityQinhuangdao 066004HebeiChina Jiangsu Shagang Group Co Ltd Zhangjiagang215625JiangsuChina

Nb is often considered to be a powerful alloying element for controlling the recrystaUization process in mi- croalloyed high strength steels. However, Nb can be presented either as solute in solution, where it is thought to ex- hibit a strong solute drag effect, or as NbC precipitates, which are thought to be effective at pinning grain bounda- ries. Therefore, it is very important to quantitatively measure Nb in solution or in NbC precipitates. A quantitative analysis method of Nb in solution and in precipitates was proposed. The test procedure involved chemical dissolution, filtration and inductively coupled plasma atomic emission spectroscopic （ICP-AES） analysis. The amount of Nb in solution in Nb-microallyed steels under different treatment conditions was evaluated. The results show that the niobium and carbon contents in steels have a great effect on niobium dissolution kinetics. The solute Nb is more effective to retard dynamic recrystallization, while the NbC precipitates are more effective to inhibit static recrystaltization. The results may help to comprehend effect of Nb in steels, and provide some guides in the design of new high strength Nb-bearing steels.

关键词： Nh microalloyed steel solution precipitation quantitative analysis recrystallization

Study on the flow field uniformity of hydro-floating ship lift combined type hydraulic-driven system based on the residual energy theory

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Journal of Hydrodynamics 2022年第6期34卷 1156-1161页

作者： bo Wu ya.an Hu Shu Xue State Key Laboratory of Water Resources and Hydropower Engineering Science Wuhan UniversityWuhan430072China State Key Laboratory of Hydrology-Water Resources and Hydraulic Engineering Nanjing Hydraulic Research InstituteNanjing210029China Key Laboratory of Transport Technology in Navigation Building Construction Nanjing Hydraulic Research InstituteNanjing210029China

The hydro-floating ship lift originally invented in China is a major innovation in the field of navigation *** shaft water levels synchronization of its unique hydraulic-driven system plays a crucial role in reducing the torque of the synchronous shafts and ensuring the safety and stability operation of the ship *** study aims to investigate the muti-shaft water level synchronization and the flow velocity uniformity of the combined type hydraulic-driven *** on the theory of residual energy,a new index m2 proposed in this study is more suitable for evaluating the flow velocity uniformity of the combined hydraulic-driven ***,the critical value of m2=75 is calculated via the results of the scaled physical mode test as the threshold of water flow uniformity,and it provides a basis for determining the reasonable height of the pressure stabilizing chamber.

关键词： Hydro-floating ship lift water levels synchronism residual energy velocity distribution uniformity coefficient

Neurotrophin signaling and visceral hypersensitivity

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Frontiers in Biology 2014年第3期9卷 216-224页

作者： Li-ya.qiao Department of Physiology and Biophysics School of Medicine Virginia Commonwealth University Richmond VA 23298 USA

Neurotrophin family are traditionally recognized for their nerve growth promoting function and are recently identified as crucial factors in regulating neuronal activity in the central and peripheral nervous systems. The family members including nerve growth factor （NGF）, brain-derived neurotrophic factor （BDNF）, and neurotrophin-3 （NT-3） are reported to have distinct roles in the development and maintenance of sensory phenotypes in normal states and in the modulation of sensory activity in disease. This paper highlights receptor tyrosine kinase （Trk） -mediated signal transduction by which neurotrophins regulate neuronal activity in the visceral sensory reflex pathways with emphasis on the distinct roles of NGF and BDNF signaling in physiologic and pathophysiological processes. Viscero-visceral cross-organ sensitization exists widely in human diseases. The role of neurotrophins in mediating neural cross talk and interaction in primary afferent neurons in the dorsal root ganglia （DRG） and neurotrophin signal transduction in the context of cross-organ sensitization are also discussed.

关键词： neurotrophin signal transduction visceral hypersensitivity cross-sensitization

Design of low-energy transfer from lunar orbit to asteroid in the Sun-Earth-Moon system

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Acta Mechanica Sinica 2014年第6期30卷 966-972页

作者： ya.Min Wang Dong qiao Ping-Yuan Cui School of Aerospace Engineering Beijing Institute of Technology Key Laboratory of Dynamics and Control of Flight Vehicle Ministry of Education

Asteroid exploration trajectories which start from a lunar orbit are investigated in this *** is assumed that the probe departs from lunar orbit and returns to the vicinity of Earth,then escapes from the Earth by performing a perigee maneuver.A low-energy transfer in Sun-EarthMoon system is ***,the feasible region of lowenergy transfer from lunar orbit to perigee within 5 000 km height above the Earth surface in Sun-Earth-Moon system is calculated and *** transfer types are found,i.e.,large maneuver and fast transfers,small maneuver and fast transfers,and disordered and slow *** of feasibility trajectories belong to the first two ***,the lowenergy trajectory leg from lunar orbit to perigee and a heliocentric trajectory leg from perigee to asteroid are patched by a perigee *** optimal full-transfer trajectory is obtained by exploiting the differential evolution ***,taking 4179 Toutatis asteroid as the target,some low-energy transfer trajectories are obtained and analyzed.

关键词： Lunar orbit Asteroid exploration Low-energy transfer Sun-Earth-Moon system

SYNTHESES,CHARACTERIZATION AND ETHYLENE POLYMERIZATION OF HALF-SANDWICH GROUP IV METAL COMPLEXES WITH TRIDENTATE [O,N,S] LIGANDS

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Chinese Journal of Polymer Science 2013年第5期31卷 760-768页

作者： ya.lin qiao Ping Hu 金国新 State Key Laboratory of Molecular Engineering of Polymers Department of ChemistryFudan University

A series of half-sandwich group IV metal complexes with tridentate monoanionic phenoxy-imine arylsulfide [O-NS] ligand [2-Bu^t4-Me-6-（（2-（SC6H5）C6H4N = CHC6H2O）]- （La） and dianionic phenoxy-amine arylsulfide [O-N-S] ligand [2-Bu^t4-Me-6-（（2-（SC6H5）C6H4N-CH2C6H2O）]2- （Lb） have been synthesized and characterized. Lb was obtained easily in high yield by reduction of ligand La with excess LiAlH4 in cool diethyl ether. Half-sandwich Group Ⅳ metal complexes CpTi[O-NS]Cl2 （1a）, CpZr[O-NS]Cl2 （1b）, CpTi[O-N-S]Cl （2a）, CpZr[O-N-S]Cl （2b） and CpZr[O-N-S]Cl （2c） were synthesized by the reactions of La and Lb with CpTiCl3, CpZrCl3 and Cp ZrCl3, and characterized by IR, ^1H-NMR, ^13C-NMR and elemental analysis. In addition, an X-ray structure analysis was performed on ligand Lb. The title Group IV half-sandwich bearing tridentate [O,N,S] ligands show good catalytic activities for ethylene polymerization in the presence of methylaluminoxane （MAO） as co-catalyst up to 1.58 × 10^7 ***-Zr-1.h-1. The good catalytic activities can be maintained even at high temperatures such as 100 ℃ exhibiting the excellent thermal stability for these half-sandwich metal pre-catalysts.

关键词： Half-sandwich group IV metal complexes Tridentate dianionic ligands Phenoxy-imine arylsulfide ligands Catalyst Ethylene polymerization

Characterization of the fracture compressibility and its permeability for shale under the effects of proppant embedment and compaction:A preliminary study

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Petroleum Science 2022年第3期19卷 1125-1138页

作者： Jian-Hua Li bo-bo Li qiao-Yun Cheng Zheng Gao Guangdong Provincial Key Laboratory of Deep Earth Sciences and Geothermal Energy Exploitation and Utilization Institute of Deep Earth Sciences and Green EnergyCollege of Civil and Transportation EngineeringShenzhen UniversityShenzhen518060GuangdongChina Shenzhen Key Laboratory of Deep Underground Engineering Sciences and Green Energy Shenzhen UniversityShenzhen518060GuangdongChina College of Mining Guizhou UniversityGuiyang550025GuizhouChina Guizhou Key Laboratory of Comprehensive Utilization of Non-metallic Mineral Resources Guiyang550025GuizhouChina National&Local Joint Laboratory of Engineering for Effective Utilization of Regional Mineral Resources from Karst Areas Guizhou UniversityGuiyang550025GuizhouChina

Hydraulic fracturing technology plays a key role in improving the recovery rate of shale *** improvement of permeability in relation to hydraulic fracturing depends on changes brought about by the proppant on the fracture structure in *** it is of great significance to describe the microscopic changes during this process by means of an accurate theoretical *** this study,based on the heterogeneity of shale fracture and the compaction and embedment of a proppant,we proposed a permeability model to examine the combined effects of a proppant and stress to describe the change mechanism in ***,changes in fracture width and porosity were considered,and a calculation model of fracture compressibility under proppant compaction and embedment was *** difference from previous studies is that the compressibility and permeability of supported fractures can be further quantified and analyzed by this ***,its rationality was verified by publicly released test *** results show that,the compressive effect of stress and the embedding of proppant both have a negative impact on shale permeability.

关键词： Shale Fracture compressibility Permeability Hydraulic fracturing Proppant embedment