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Chinese Journal of Polymer Science 2021年第9期39卷 1161-1168页

作者： Dan-Ni Gao Yu-Lai zhao Jing-Yu Cai Lin-xi Hou Long-Qiang xiao Department of Materials-Oriented Chemical Engineering School of Chemical EngineeringFuzhou UniversityFuzhou 350116China Qingyuan Innovation Laboratory Quanzhou 362801China Fujian Key Laboratory of Advanced Manufacturing Technology of Specialty Chemicals Fuzhou UniversityFuzhou 350116China

Reversible chain transfer catalyzed polymerization(RTCP)is a practical and efficient process for the precise synthesis of polymers with special architecture by using simple phenols(2,4,6-trimethylphenol,TMP)or hydrocarbons(xanthene,XT)as efficient ***,alkyl iodide(R-1),which was gen erated from in situ bromine-iodine transformation of alkyl bromide(R-Br)with sodium iodide(Nal),was served as initiator to mediate RTCP with TMP or *** and other functional methacrylates,including GMA,DEAM,DMAEMA and BzMA,were successfully initiated by combining orga no catalysts and azo in itiators to yield polymers with low-polydispersity(M_(w)/M_(n)=1.1-1.5)and ideal mono mer conversions(50%-90%)at moderate *** over,3-armstar polymers were also obtained by this *** high chain-end fidelity of the obtained poly(methyl methacrylate)with iodine as chain-end group(PMMA-I)was confirmed by chain-extension *** en vironme ntally frie ndly initiators and orga no catalysts exhibit powerful polymerization properties toward RTCP,providing a sign ificant method to synthesize functional polymers.

关键词： Reversible chain transfer catalyzed polymerization Organocatalyst Halogen exchange

Fabrication of organically modified oxygen sensing film based on fluorescent quenching

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Chinese Science Bulletin 2007年第2期52卷 188-193页

作者： xiN LingLing xiao LaiLong zhao Li CHEN xi WANG xiaoRu Department of Chemistry and the Key Laboratory of Analytical Sciences of Ministry of Education College of Chemistry and Chemical Engineering Xiamen University Xiamen 361005 China State Key Laboratory of Marine Environmental Science Xiamen University Xiamen 361005 China

An organically modified silicate (ORMOSIL) as a matrix for oxygen-sensitive sensor, in which di-methyldimethoxysilane was selected as an organic modifier in the precursor, is described. The sensing film with tris-(4,7-diphenyl-1,10-phenanthroline) ruthenium(II) as an indicator developed in this paper was characterized by efficient quenching by oxygen. Blue light-emitting diodes (λmax = 475 nm) were employed as light excitation source. The linear range of the dissolved oxygen was from 0.5 to 16 μg/mL. The measured RSD was 2%, the response time (t95) was 60 s, and the determination limit was 0.2 μg/mL. A portable and inexpensive luminescence-based sensor was established and applied to the determina-tion of dissolved oxygen in the surface water.

关键词：改性有机硅钌邻二氮杂菲发光

Tuning the interfacial reaction environment via pH-dependent and induced ions to understand C–N bonds coupling performance in NO3- integrated CO2 reduction to carbon and nitrogen compounds over dual Cu-based N-doped carbon catalyst

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Journal of Energy Chemistry 2025年第1期100卷 273-285页

作者： Tianhang Zhou Chen Shen Zhenghao Wu xingying Lan Yi xiao College of Carbon Neutrality Future Technology State Key Laboratory of Heavy Oil Processing China University of Petroleum (Beijing) Institute of Materials Science TU Darmstadt Department of Chemistry Xi'an Jiaotong-Liverpool University Department of Mechanical and Mechatronics Engineering and Waterloo Institute of Nanotechnology University of Waterloo Waterloo

Dual atomic catalysts （DAC）,particularly copper （Cu2）-based nitrogen （N） doped graphene,show great potential to effectively convert CO2and nitrate （NO3-） into important industrial chemicals such as ethylene,glycol,acetamide,and urea through an efficient catalytical process that involves C–C and C–N ***,the origin of the coupling activity remained unclear,which substantially hinders the rational design of Cu-based catalysts for the N-integrated CO2reduction reaction （CO2RR）.To address this challenge,this work performed advanced density functional theory calculations incorporating explicit solvation based on a Cu2-based N-doped carbon (Cu2N6C10) catalyst for *** calculations are aimed to gain insight into the reaction mechanisms for the synthesis of ethylene,acetamide,and urea via coupling in the interfacial reaction *** to the sluggishness of CO2,the formation of a solvation electric layer by anions （F-,Cl-,Br-,and I-） and cations (Na+,Mg2+,K+,and Ca2+) leads to electron transfer towards the Cu *** process significantly accelerates the reduction of *** results reveal that*CO intermediates play a pivotal role in N-integrated ***,the Cu2-based N-doped carbon catalyst examined in this study has demonstrated the most potential for C–N coupling to *** findings reveal that through the process of a condensation reaction between*CO and NH2OH for urea synthesis,*NO3-is reduced to*NH3,and*CO2to*CCO at dual Cu atom *** dual-site reduction facilitates the synthesis of acetamide through a nucleophilic reaction between NH3and the ketene ***,we found that the I-and Mg2+ions,influenced by pH,were highly effective for acetamide and ammonia synthesis,except when F-and Ca2+were ***,the mechanisms of C–N bond formation were investigated via ab-initio molecular dynamics simulations,and we found that adjusting the micro-environment can change the dominant side reaction,shift

关键词： pH-dependent micro-environments C–N coupling Dual Cu-based nitrogen carbon catalysts Explicit solvation model Ion stabilizer AIMD

Conjecture on the Time Scales of Intramolecular Dynamics and Lyapunov Relaxation

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Chinese Physics Letters 1997年第5期14卷 336-339页

作者： xiE xi-shun HUANG xiao-qin zhao Mei-shan Department of Physics Southeast UniversityNanjing 210096 Department of Physics Nanjing Normal UniversityNanjing 210097 The James fianck Institute The University of ChicagoChicagoIllinois 60637U.S.A.

A dynamical study of intramolecular energy transfer in a realistic polyatomic model molecular system is *** the present study and dynamical information established in the previous research we make the conjecture that ... 详细信息

关键词： dynamical relaxation Lyapunov

Magneto-optic Crystal Polarization Controller Assisted Mode-Locked Fiber Laser

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Chinese Physics Letters 2011年第3期28卷 81-84页

作者： zhao Guang-Zhen GUI Li-Li xiao xiao-Sheng YANG Chang-xi State Key Laboratory of Precision Measurement Technology and Instruments Department of Precision InstrumentsTsinghua UniversityBeijing 100084

We report a passively mode-locked erbium-doped fiber laser based on a compact magneto-optic crystal polarization *** length of the polarization controller consisting of four magneto-optic crystal rotators and two quarter wave-plates is only *** the polarization controller,central wavelength around 1559nm and repetition rate 21.10 MHz mode-locked pulse are *** duration and 3 dB spectrum width are 598.4fs and 6.24nm *** pulse energy is about *** of its small size,low insertion loss,good controllability and negligible dispersion,the magneto-optic crystal polarization controller could be an ideal polarization controller in fiber lasers.

关键词： polarization fiber passive

Control of Macrosegregation Behavior by Applying Final Electromagnetic Stirring for Continuously Cast High Carbon Steel Billet

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Journal of Iron and Steel Research International 2013年第11期20卷 13-20页

作者： xiao Chao ZHANG Jiong-ming LUO Yan-zhao WEI xiao-dong WU Lian WANG Shun-xi State Key Laboratory of Advanced Metallurgy University of Science and Technology Beijing School of Metallurgical and Ecological Engineering University of Science and Technology Beijing

Solidification behavior of continuously cast high carbon steel billets was investigated with an objective of producing high quality billets by determining the optimum final electromagnetic stirring （F-EMS） parameters. Char- acteristics of centerline segregation were analyzed for lots of billet samples collected from the plant through obtaining the carbon concentrations of drill chips, which were correlated with the operating parameters of the caster and stir- rers, but a problem occurred that segregation control results of trial billets with the same casting and stirring param- eters often have drastic fluctuations. An attempt was made to find out the induced reasons of this problem by meas uring the electromagnetic torque, analyzing the secondary dendrite arm spacing （SDAS） and the corresponding cool- ing rate of the typical specimens, and observing the longitudinal profile of etched billet samples. Then a simple dy- namic secondary cooling model was developed based on the solidified shell thickness control mode, by which the maximum carbon segregation index was reduced effectively, and thus the segregation fluctuation problem was basi- cally solved. Finally, the most favourable stirring parameters were determined as the casting speed of 1.65 m/rain, the liquid core thickness of 40 mm, stirring current of 360 A and frequency of 12 Hz.

关键词： F-EMS carbon segregation index SDAS cooling rate stirring parameter

Multiple Dissipative Solitons in a Long-Cavity Normal-Dispersion Mode-Locked Yb-Doped Fiber Laser

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Chinese Physics Letters 2012年第3期29卷 107-110页

作者： zhao Guang-Zhen xiao xiao-Sheng MEI Jia-Wei YANG Chang-xi State Key Laboratory of Precision Measurement Technology and Instruments Department of Precision InstrumentsTsinghua UniversityBeijing 100084

Transitional operations of multiple dissipative solitons in a long-cavity normal-dispersion Yb-doped fiber laser are experimentally *** dissipative solitons,including a stable soliton pair and a soliton triplet are observed by increasing the pump power or adjusting the polarization *** main boundaries of the stable asymmetric soliton and oscillating soliton are found between steady ***,multiple dissipative solitons with greater quantities of solitons are observed with pump power *** experimental results agree well with a previous numerical study of multiple dissipative solitons.

关键词： soliton solitons dissipative

Essentially Commuting Truncated Toeplitz Operators

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Acta Mathematica Sinica,English Series 2024年第10期40卷 2453-2480页

作者： xi zhao Tao YU School of Mathematics and Science Hebei GEO University Shijiazhuang 050031P.R.China School of Mathematical Sciences Dalian University of Technology Dalian 116024P.R.China

A model space is a subspace of the Hardy space which is invariant under the backward shift,and a truncated Toeplitz operator is the compression of a Toeplitz operator on some model *** this paper we prove a necessary ... 详细信息

关键词： Truncated Toeplitz operator model space commutator maximal ideal space compact operator

Investigation of the spike-stall warning method using the blade passing signal

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Science China(Technological Sciences) 2018年第6期61卷 830-842页

作者： zhao JiaYi xi Guang WANG ZhiHeng zhao Yang School of Energy and Power Engineering Xi＇an Jiaotong University Xi ＇an 710049 China

The vaned-diffuser usually brings compressor instability problems under the small flow rate, for instance the spike-type rotating stall phenomenon which restricts the operation range and may cause the trouble of blade fatigue. Since it is difficult to mathematically predict the spike-type stall for its randomness, finding out a practical method to warning this stall precursor appears to be meaningful. The paper explains the relationship between the spike-type precursor and the blade passing irregularity coefficient to analyze whether this coefficient is appropriate for the spike-stall warning inside a centrifugal compressor with the vaned-diffuser. The advanced wireless measurements were conducted on a 1.5 stages test centrifugal compressor to capture the unsteady behavior progressing from the design to stall inception within the region between the impeller trailing edge(TE) and diffuser leading edge(LE). The circumferential distribution of the blade passing irregularity has been quantitatively *** steep increase of the blade passing irregularity at some "special locations", which is responsible for the onset of the spiketype precursor, is highlighted. Also, to further understand the spike precursor inside the diffuser passage corresponding to the circumferential "special location" with maximum irregularity, the high-response transient measurement within this passage is presented. With the help of full-annulus computational fluid dynamics(CFD) simulation and the mathematical model, it is proved that the blade passing irregularity precisely reflects the flow characteristics during the spike precursor, which presents the guidance for this stall warning method.

关键词： centrifugal compressor transient measurement stall warning blade passing irregularity coefficient

Experimental study of dual nano-network, high-temperature resistant aerogel material as an integration of thermal management functions

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Journal of Energy Chemistry 2025年第1期 157-170页

作者： Yueyue xiao Tianke Mao Zun zhao Yuelei Pan Heping Zhang Xudong Cheng State Key Laboratory of Fire Science University of Science and Technology of China

Thermal management system is highly desirable to guarantee the performance and thermal safety of lithium-ion batteries,but it reduces the energy density of battery modules and even is unable to provide highly effective ***,a thermal management function integrated material is presented based on high-temperature resistant aerogel and phase change material and is applied at both charge–discharge process and thermal runaway *** this sandwich structure Paraffin@SiC nanowire/Aerogel sheet （denoted as PA@SAS） system,SiC nanowires endow the middle aerogel sheet （SAS） a dual nano-network *** enhanced mechanical properties of SAS were studied by compressive tests and dynamic mechanical ***,the thermal conductivity of SAS at 600°C is only 0.042 W/（m K）.The surface phase change material layers facilitate temperature uniformity of batteries （surface temperature difference less than 1.82°C） through latent ***,a large-format battery module with four 58 Ah LiNi0.5Co0.2Mn0.3O2LIBs was ***@SAS successfully prevents thermal runaway propagation,yielding a temperature gap of 602°C through the 2 mm-thick cross ***@SAS also exhibits excellent performance in other safety issues such as temperature rise rate,flame heat flux,*** lightweight property and effective insulation performance achieves significant safety enhancement with mass and volume energy density reduction of only 0.79%and 5.4%,*** originality of the present research stems from the micro and macro structure design of the proposed thermal management material and the combination of intrinsic advantages of every *** work provides a reliable design of achieving the integration of thermal management functions into an aerogel composite and improves the thermal safety of lithium-ion batteries.

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