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Non-linear Radical Additions-Coupling Polymerization of Monovinyl Monomers towards Polymer Networks: Theory, Tunability and Heritable Architecture

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Chinese Journal of Polymer Science 2022年第12期40卷 1623-1630,I0008页

作者： li-Mei Ren cheng-lin li Qi Wang MOE Key Laboratory of Macromolecular Synthesis and Functionalization Department of Polymer Science&Engineering Zhejiang UniversityHangzhou 310027China Current address:Zhejiang University-University of Edinburgh Institute Zhejiang University School of Medicineand Key Laboratory of Tissue Engineering and Regenerative Medicine of Zhejiang ProvinceZhejiang University School of MedicineHangzhou 310027China

Exploring new polymerization strategy for current available monomers is a big challenge in polymer science. Here we re-investigate radical polymerization of monovinyl monomer(MVM) initiated by uniform branched polyfunctional initiator(PFI), which is termed non-linear radical additions-coupling polymerization(NLRAs CP). In NLRAs CP, both addition and coupling reactions of radical contribute to the construction of the polymer chains, which leads to continuous growth of branch topology. Theoretical analysis of NLRAs CP predicts that the gelation is determined by the functionality of PFI(a), the extent of initiation of the PFI(q) and the termination factor of radical(φ). NLRAs CPs of styrene and methyl methacrylate promoted by Cu(0)/MeTREN or Mn_(2)(CO)_(10)/visible light were conducted. After the cleavage of incorporated PFI fragment or junctions in the network, the network was transformed to linear chains having almost the same structure as segmental chains in the precursor network. This allows the reverse deducing the network structure from its cleaved products. It has been proven that NLRAs CP includes stepwise initiation of PFI, chain-growth of segmental chains and successive endlinking of macroradicals derived from PFI. The three parameters related to the gelation process, a, q and φ, were adjusted via binary PFI, the feed ratio of [Mn_(2)(CO)_(10)]/[PFI] and addition of non-homopolymerizable comonomer respectively. The minimum values of a and q, and the minimum amount of comonomer required for gelation were determined,which can be applied to estimate φ of various macroradicals. NLRAs CP opens a general and facile strategy for synthesis of a variety of polymer networks with heritable architecture by one-pot polymerization of various MVMs.

关键词： Non-linear radical additions-coupling polymerization Monovinyl monomer Polyfunctional initiator Polymer network Theory

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A Simulation Experiment of a Pipeline Based on Machine Learning for Neutral Hydrogen Intensity Mapping Surveys

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Research in Astronomy and Astrophysics 2022年第11期22卷 61-68页

作者： lin-cheng li Yuan-Gen Wang School of Computer Science and Cyber Engineering Guangzhou UniversityGuangzhou 510006China

We present a simulation experiment of a pipeline based on machine learning algorithms for neutral hydrogen(H I)intensity mapping(IM)surveys with different *** simulation is conducted on H I signals,foreground emission,thermal noise from instruments,strong radio frequency interference(s RFI),and mild RFI(m RFI).We apply the Mini-Batch K-Means algorithm to identify s RFI,and Adam algorithm to remove foregrounds and m *** show that there exists a threshold of the s RFI amplitudes above which the performance of our pipeline enhances *** removing foregrounds and m RFI,the performance of our pipeline is shown to have little dependence on the apertures of *** addition,the results show that there are thresholds of the signal amplitudes from which the performance of our pipeline begins to change *** consider all these thresholds as the edges of the signal amplitude ranges in which our pipeline can function *** work,for the first time,explores the feasibility of applying machine learning algorithms in the pipeline of IM surveys,especially for large surveys with the next-generation telescopes.

关键词： cosmology:observations methods:statistical radio lines:galaxies

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Microstructure and mechanical properties of a new high-strength and high-toughness titanium alloy

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Rare Metals 2023年第1期42卷 281-287页

作者： Dong li Song-Xiao Hui Wen-Jun Ye cheng-lin li State Key Laboratory for Nonferrous Metals and Processes General Research Institute for Nonferrous MetalsBeijing100088China

In order to develop a new titanium alloy with a good combination of strength-ductility-toughness,a nearbeta titanium alloy was designed based on the already widely used Ti-1023 *** avoid beta fleck occurring in the microstructure,the new Ti-Al-Fe-V(Cr,Zr) alloy has been made through decreasing the content of Fe,based on molybdenum equivalency and Bo-Md molecular orbital method(a method for new alloy designing based on the molecular orbital calculating).After primary design computation,Ti-Al-Fe-V(Cr,Zr) alloy was optimized as Ti-3Al-4.5Cr-1Fe-4V-1Zr *** microstructure and tensile properties of this alloy subjected to several commonly used heat treatments were *** results show that the tensile strength of the alloy after solution treated below the β-transus temperature comes between 850 and 1100 MPa,with elongation in the range of 12.5 %-17.0 %.In solution-treated and solution-aged samples,a low-temperature aging at 500 ℃ results in the precipitation of finer α *** the increase in aging temperature,the secondary α phase becomes coarser and decreases in ***,it will lead to the increase in tensile ductility,but reduction in ***,after modulated aging treatment,the alloy can obtain highstrength level with acceptable *** tensile strength of the alloy can achieve 1273 MPa,with an elongation of 11.0 %.At the same time,the fracture toughness(K_(IC)) of the alloy achieves 83.8 MPa·m^(1/2).It is obvious that the newly designed alloy has achieved a good blend of strength-ductility-toughness.

关键词： Beta titanium alloy Microstructure Tensile/toughness property

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An HI intensity mapping survey with a Phased Array Feed

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Research in Astronomy and Astrophysics 2021年第2期21卷 41-51页

作者： lin-cheng li lister Staveley-Smith Jonghwan Rhee National Astronomical Observatories Chinese Academy of SciencesBeijing 100101China School of Astronomy and Space Science University of Chinese Academy of SciencesBeijing 100049China International Centre for Radio Astronomy Research(ICRAR) The University of Western Australia35 Stirling HwyCrawleyWA6009Australia ARC Centre of Excellence for All-sky Astrophysics(CAASTRO) Perth6009Australia ARC Centre of Excellence for All Sky Astrophysics in 3 Dimensions(ASTRO 3D) Perth6009Australia

We report results from a neutral hydrogen(H I)intensity mapping survey conducted with a Phased Array Feed(PAF)on the Parkes *** survey was designed to cover 380 deg^(2)over the redshift range 0.3line was described,with an emphasis on flagging of RFI and correction for signal loss in the data reduction process,particularly due to the foreground subtraction methodology.A cross-correlation signal was detected between the H I intensity maps and the Wiggle Z redshift data,with a mean amplitude of=1.32±0.42 m K(statistical errors only).A future Parkes cryogenic PAF is expected to detect the cross-correlation signal with higher accuracy than previously possible and allow measurement of the cosmic H I density at redshifts up to unity.

关键词： cosmology observation-methods statistical-radio lines galaxy

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Morphology control of magnetic properties in cobalt nanowires

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Rare Metals 2023年第6期42卷 1994-1999页

作者： Huan-Huan Xu Qiong Wu Ming Yue cheng-lin li Hong-Jian li College of Materials Science and Engineering Beijing University of TechnologyBeijing100124China

Cobalt nanowires with different shapes and sizes were synthesized by reduction of carboxylate salts of Co^(Ⅱ) in 1,2-butanediol using a solvothermal chemical *** well-crystallized Co nanowires with hexagonal closepacked(hep) phase are observed and the(002) crystalline direction is along the long axis of nano *** morphology control is strongly dependent on the reaction *** varying the amount of capping agent in proper ranges,the effect of reaction parameters on controlling the size and shape of Co nanowires is *** the amount of capping agent increasing,the aspect ratio of Co nanowires increases ***,the magnetic measurement of cobalt nanowires shows that the coercivity of the Co nanocrystals does not increase with the increase in aspect ratio monotonously,which suggests that the tip shape and micros tructure also play an important role in the magnetization reversal process of the Co nanocrystals,and the aspect ratio plays a much less role as the ratio value exceeds *** further understand the effect of size on the magnetic properties in the Co nanowires,micromagnetic simulations were performed,which confirms that the magnetic properties are barely affected by the aspect ratio larger than *** highest coercivity of624 kA·m^(-1) is obtained for ellipsoid nano wires with a mean length of 200 nm,which also displays a strong magnetic *** a result,the highest energy product of the wires reaches 248 kJ·m^(-3).

关键词： Co nanowires Morphology control Tip shape High energy product

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Preparation and characterization of Fe_2O_3-CeO_2-TiO_2/γ-Al_2O_3 catalyst for degradation dye wastewater

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Journal of Environmental Sciences 2006年第6期18卷 1189-1192页

作者： liU Yan SUN De-zhi cheng lin li Yan-ping School of Municipal and Environmental Engineering Harbin Institute of Technology Harbin 150090 China

In order to develop a catalyst with high activity for catalytic wet oxidation （CWO） process at room temperature and atmospheric pressure, Fe2O3-CeO2-TiO2/γ-Al2O3 catalyst was prepared by consecutive impregnation method and the prepared parameters were optimized. The structure of the catalyst was characterized by BET, XRF, SEM and XPS technologies, and the actual wastewater was used to investigate the catalytic activity of Fe2O3-CeO2-TiO2/γ-Al2O3 in CWO process. The experimental results showed that the prepared catalyst exhibited good catalytic activity when the doping amount of Ti was 1.0 wt% （the weight ratio of Ti to carriers）, and the middle product, Fe2O3-CeO2-TiO2/γ-Al2O3, was calcined in 450℃ for 2 h. The CWO experiment for treating actual dye wastewater indicated that the COD, color and TOC of actual wastewater were decreased by 62.23%, 50.12% and 41.26% in 3 h, respectively, and the ratio of BOD5/COD was increased from 0.19 to 0.30.

关键词： catalytic wet oxidation (CWO) Fe2O3-CeO2-TiO2/γ-Al2O3 catalyst dye wastewater treatment

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The conformity of HI galaxies in ALFALFA-SDSS sample

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Research in Astronomy and Astrophysics 2021年第2期21卷 61-67页

作者： lin-cheng li Bo Qin Jie Wang Jing Wang You-Gang Wang National Astronomical Observatories Chinese Academy of SciencesBeijing 100101China School of Astronomy and Space Science University of Chinese Academy of SciencesBeijing 100049China International Centre for Radio Astronomy Research(ICRAR) The University of Western Australia35 Stirling HwyCrawleyWA6009Australia Department of Astronomy Peking UniversityBeijing 100871China

The conformity effect,indicating the evolution of galaxies is related to its surrounding neighbor galaxies as far as a few Mpc,is an interesting phenomenon in the modeling of galaxy and *** we study the conformity effect of HI galaxies in a matched galaxy sample between SDSS DR7 and ALFALFA *** checking the probability difference for the detected H i galaxies as a function of distance around a normal or an H i galaxy,we find that this effect is significant out to 5 *** also shows a dependence on the stellar mass of galaxies,with the strength the strongest in the stellar mass range of 10^(10)light on the co-evolution of the galaxies and their neighbors in the current galaxy formation models.

关键词： method data analysis-radio lines galaxies-galaxies evolution

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Research progress on hot deformation behavior of high-strength β titanium alloy: flow behavior and constitutive model

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Rare Metals 2022年第5期41卷 1434-1455页

作者： Chang-Min li liang Huang cheng-lin li Song-Xiao Hui Yang Yu Ming-Jie Zhao Shi-Qi Guo Jian-Jun li State Key Laboratory of Materials Processing and Die and Mould Technology School of Materials Science and EngineeringHuazhong University of Science and TechnologyWuhan 430074China School of Power and Mechanical Engineering Wuhan UniversityWuhan 430074China State Key Laboratory of Nonferrous Metals and Processes General Research Institute for Nonferrous MetalsBeijing 100049China

High-strength β titanium alloys represented by near β titanium alloy and metastable β titanium alloy are preferred materials for large-scale load-carrying *** order to achieve the precise regulation of microstructure in the deformation process, massive efforts have been made to study the flow behavior and microstructure evolution of βtitanium alloy in the hot deformation process. This paper reviews the flow behavior of high-strength titanium alloy,including the effects of initial microstructure, deformation process parameters, work hardening, and dynamic softening on flow stress. Furthermore, the effects of deformation process parameters on the apparent activation energy for deformation and strain rate sensitivity coefficient are analyzed. The discontinuous yield phenomenon is discussed,and the constitutive models of flow stress are ***, some microstructural evolution models are reviewed. Finally, the development direction and difficulties of the flow behavior and constitutive model are pointed out.

关键词： High-strengthβtitanium alloy Hot deformation Flow behavior Constitutive model

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Reactor field reconstruction from sparse and movable sensors using Voronoi tessellation-assisted convolutional neural networks

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Nuclear Science and Techniques 2024年第5期35卷 173-185页

作者： He-lin Gong Han li Dunhui Xiao Sibo cheng Paris Elite Institute of Technology Shanghai Jiao Tong UniversityShanghai 200240China School of Mathematical Sciences Tongji UniversityShanghai 200092China Department of Computing Data Science InstituteImperial College LondonLondon SW72AZUK

The aging of operational reactors leads to increased mechanical vibrations in the reactor *** vibration of the incore sensors near their nominal locations is a new problem for neutronic field *** field-reconstruction methods fail to handle spatially moving *** this study,we propose a Voronoi tessellation technique in combination with convolutional neural networks to handle this *** from movable in-core sensors were projected onto the same global field structure using Voronoi tessellation,holding the magnitude and location information of the *** convolutional neural networks were used to learn maps from observations to the global *** proposed method reconstructed multi-physics fields(including fast flux,thermal flux,and power rate)using observations from a single field(such as thermal flux).Numerical tests based on the IAEA benchmark demonstrated the potential of the proposed method in practical engineering applications,particularly within an amplitude of 5 cm around the nominal locations,which led to average relative errors below 5% and 10% in the L_(2) and L_(∞)norms,respectively.

关键词： Voronoi tessellation Field reconstruction Nuclear reactors Reactor physics On-line monitoring

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Functional Optical Fiber Sensors Detecting Imperceptible Physical/Chemical Changes for Smart Batteries

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Nano-Micro Letters 2024年第8期16卷 268-308页

作者： Yiding li li Wang Youzhi Song Wenwei Wang cheng lin Xiangming He Institute of Nuclear and New Energy Technology Tsinghua UniversityBeijing 100084People’s Republic of China National Engineering Research Center of Electric Vehicles Beijing Institute of Technology(BIT)Beijing 100081People’s Republic of China Shenzhen Automotive Research Institute of BIT(Shenzhen Research Institute of National Engineering Research Center of Electric Vehicles) Shenzhen 518118People’s Republic of China

The battery technology progress has been a contradictory process in which performance improvement and hidden risks *** the battery is still a“black box”,thus requiring a deep understanding of its internal *** battery should“sense its internal physical/chemical conditions”,which puts strict requirements on embedded sensing *** paper summarizes the application of advanced optical fiber sensors in lithium-ion batteries and energy storage technologies that may be mass deployed,focuses on the insights of advanced optical fiber sensors into the processes of one-dimensional nano-micro-level battery material structural phase transition,electrolyte degradation,electrode-electrolyte interface dynamics to three-dimensional macro-safety *** paper contributes to understanding how to use optical fiber sensors to achieve“real”and“embedded”*** the inherent advantages of the advanced optical fiber sensor,it helps clarify the battery internal state and reaction mechanism,aiding in the establishment of more detailed *** advancements can promote the development of smart batteries,with significant importance lying in essentially promoting the improvement of system ***,with the help of smart batteries in the future,the importance of consistency can be weakened or even *** application of advanced optical fiber sensors helps comprehensively improve the battery quality,reliability,and life.

关键词： Smart battery Advanced embedded optical fiber sensor Battery internal physical/chemical state Quality-reliability-life characteristic

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