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NOVEL SYNTHESIS OF LONG MULTI-BLOCK HETEROPOLYMER CHAINS WITH AN ORDERED SEQUENCE AND CONTROLLABLE BLOCK LENGTHS

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Chinese Journal of Polymer Science 2001年第5期19卷 451-454页

作者： Chi Wu Zuo-wei Xie Guang-zhao Zhang guo-fu zi Department of Chemistry, The Chinese University of Hong Kong Shatin, N.T., Hong Kong China Chinese Univ Hong Kong Dept Chem Shatin Hong Kong Peoples R China

It had very long been a dream in polymer science to synthesize long multi-block polymer chains with an orderedchain sequence and controllable block lengths. Using ionic or living free radical polymerization or furnishing each end ofpolymer blocks with a reactive functional group, one can only prepare heteropolymer chains with few long blocks, such asdiblock and triblock copolymers. The most plausible result so far was a pentablock copolymer. Recently, using a combinationof polymer physics and synthetic chemistry, we have invented self-assembly assisted polycondensation (SAAP). Thiscommunication reports the results of using this novel. method to connect 10-100 triblock polymer chains together to formlong multi-block heteropolymer chains with an ordered sequence and controllable block lengths.

关键词： multi-block copolymer self assembly self assembly assisted polypolymerization novel polymer synthesis

Thermodynamic and experimental study of high-temperature roasting of blast furnace gas ash for recovery of metallic zinc and iron

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Journal of Iron and Steel Research International 2024年第1期31卷 108-120页

作者： zi-han Wang Jing guo Han-jie guo Bin Li School of Metallurgical Engineering University of Science and Technology BeijingBeijing100083China School of Metallurgical Engineering Xi’an University of Architecture and TechnologyXi’an710055ShaanxiChina

A high-temperature reduction roasting method was used to achieve metallic iron and zinc recovery from blast furnace gas ash(BFA).The reduction processes for Zn-containing and Fe-containing oxides were analyzed in detail by using ther-modynamic equilibrium calculation and the principle of minimum free *** results showed that the main reaction in the system is the reduction of ZnFe_(2)_(4)and iron *** the full temperature range,iron oxides were more easily reduced than zinc *** of the amount of CO contained in the system,the reduction of ZnO to Zn was difficult to proceed below the boiling point(906℃)of *** the reduction temperature is below 906℃,the reduction process of zinc ferrate was ZnFe_(2)_(4)→ZnO;when the reduction temperature is above 906℃,its reduction process becomed ZnFe_(2)_(4)→ZnO→Zn(g).The metallization and dezincification rates of the BFA gradually increased with increasing reaction *** the C/O ratio increased,the metallization and dezincification rates first increased and then *** effect of reduction time on BFA reduction was similar to that of reaction temperature.

关键词： Blast furnace gas ash Thermodynamics zinc removal Iron reduction High-temperature reduction roasting Integrated utilization

Asymmetric Trimethylsilylcyanation of Benzaldebyde Catalyzed by Novel Ti(Ⅳ)-Chiral Schiff Base Complexes

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Chinese Chemical Letters 1997年第12期8卷 0-0页

作者： guo fu zi Cheng Lie YIN(Department of Chemistry, Beijing Normal University, Beijing, 100875)

Benzaldehyde has been trimethylsilylcyanated with a catalyst prepared in situ from titanium tetraisopropoxide and chiral Schiff bases. Cyanohydrin is obtalned in moderate ***

关键词： Asymmetric Trimethylsilylcyanation of Benzaldebyde Catalyzed by Novel Ti Chiral Schiff Base Complexes Base

Evolution of copper species during heat treatment and its effect on CO oxidation reaction on CuCeZrO_(y) catalyst synthesized by a facile solvent-free route

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Journal of Rare Earths 2024年第4期42卷 660-667页

作者： Guangying fu Dongsen Mao Jun Yu Qiangsheng guo School of Chemical and Environmental Engineering Shanghai Institute of TechnologyShanghai21418 China The ZeoMat Group Qingdao Institute of Bioenergy and Bioprocess TechnologyCASQingdao26611China

Several ternary oxides CuCeZrO_(y)(CCZ)were synthesized by a facile grinding method followed by calcination at high temperatures,and used as catalysts for CO oxidation at low *** influences of calcination temperature(400-600℃)on the physicochemical properties of the assynthesized ternary oxides were investigated by thermogravimetric analysis/differential scanning calorimetry(TGA/DSC),X-ray diffraction(XRD),transmission electron microscopy(TEM),Raman,inductively coupled plasma-optical emission spectrometry(ICP-OES),N_(2) adsorption,H_(2)-temperature programmed reduction(H_(2)-TPR),and X-ray photoelectron spectroscopy(XPS)*** results show that the increase in calcination temperature from 400 to 500℃is conducive to the high dispersion of CuOx on catalyst surface and the incorporation of Cu species into the support to form the Cu-Ce-Zr-O solid *** raising of calcination temperature from 500 to 600℃,however,leads to the segregation of Cu species from the solid solution to aggregate on support surface and growth of highly dispersed CuOx *** highest catalytic activity is acquired over the CCZ calcined at 500℃,which can be ascribed to the largest contents of Cu+species and oxygen vacancies owing to the formation of the maximum amount of Cu-Ce-Zr-O solid solution.

关键词： CuCeZrO_(y)catalyst co oxidation Calcination temperature Grinding method Oxalate precursor Rare earths

Carbon nanofibers embedded with Fe-Co alloy nanoparticles via electrospinning as lightweight high-performance electromagnetic wave absorbers

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Rare Metals 2024年第6期43卷 2769-2783页

作者： Wen-Jun Cai Jian-guo Jiang zi-Dong Zhang zi-Xuan Liu Lu-JieZhang Zhen-Kun Long Ke Bi Key Laboratory for Liquid-Solid Structural Evolution and Processing of Materials(Ministry of Education) Shandong UniversityJinan 250061China School of Materials Science and Engineering Shandong UniversityJinan 250061China Energy Institute Qilu University of Technology(Shandong Academy of Sciences)Jinan 250014China State Key Laboratory of Information Photonics and Optical Communications School of ScienceBeijing University of Posts and TelecommunicationsBeijing 100876China

As a lot of electromagnetic pollution and interference issues have emerged,to overcome electromagnetic interference,prevent electromagnetic hazards,and develop new high-performance electromagnetic wave(EMW)absorbers have become a significant task in the field of materials *** this paper,a three-dimensional(3D)carbon nanofibers network with core-shell structure,embedded with varied molar ratios of iron and cobalt(4:0,3:1,2:2,1:3,0:4),was effectively synthesized(Fe/Co@C-CNFs)via *** phase,microstructure,magnetic and EMW absorption properties were *** is discovered that Fe/Co@C-CNFs doped with iron:cobalt=1:1 have excellent EMW absorption *** the matching thickness is 1.08 mm,the minimum reflection loss(RL)value is-18.66 dB,while the maximum effective absorption bandwidth(EAB)reaches 4.2 GHz(13.9-18 GHz)at a thickness of 1.22 *** is owing to the absorbers'superior impedance matching and multiple reflections as well as the conductivity,dielectric,and magnetic losses of carbon nanofibers embedded with Fe-Co alloy *** addition,the radar cross section(RCS)of the absorbers has been calculated by CST Studio Suite,showing that the absorbing coating can effectively reduce the RCS at various angles,especially for Fe/Co@C-CNFs doped with iron:cobalt=1:*** findings not only provide new insights for the preparation of light-weight and high-performance electromagnetic wave absorbers,but also contribute to energy storage and conversion.

关键词： Electromagnetic wave(EMW)absorbers Fe/Co@C-CNFs Core-shell structure EMW absorbing mechanism Radar cross section(RCS)

Correlation between longitudinal crack occurrence and mold heat transfer in continuous casting based on process data mining

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Journal of Iron and Steel Research International 2024年第5期31卷 1139-1152页

作者： Zhi-qiang Peng zi-bing Hou Kai Yi Kun-hui guo Dong-wei guo Guang-hua Wen College of Materials Science and Engineering Chongqing UniversityChongqing400044China Chongqing Key Laboratory of Vanadium-Titanium Metallurgy and New Materials Chongqing UniversityChongqing400044China

The correlation between the longitudinal crack occurrence and integrated heat transfer of the mold with data mining methods was ***,three kinds of support vector machine models based on principal component analysis with different input features were established to explore the effect of integrated heat transfer on the accuracy of the prediction model for the longitudinal *** results show that the accuracy was improved while features including mean and standard deviation of integrated heat transfer were ***,the difference in integrated heat transfer between defect and normal samples under the same process parameters was quantitatively *** with normal samples,the temperature difference of cooling water for defect samples decreased by 0.65%,and the temperature difference fluctuation increased by 31.1%.Finally,the literature data were used to provide support for the quantitative correlation according to defect formation mechanism.A new criterion for the prediction of longitudinal crack and a discovering method for correlation between product quality and process parameters in the manufacturing industry have been provided.

关键词： Continuous casting slab Longitudinal surface crack Heat transfer Data mining Quantitative correlation

Antibonding orbital tailor and stress relief engineering for FeS2 complex toward superior sodium storage

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Rare Metals 2024年第10期43卷 5048-5059页

作者： You-Bin Zhang Zhen-guo Qi fu-Sheng Liu guo-Hui Qin State Key Laboratory Base for Eco-Chemical Engineering College of Chemical EngineeringQingdao University of Science and Technology Shandong Synergetic Innovation Center of Ecological and Chemical Engineering

The sluggish kinetics behaviors and vast volume variations of Na+hosts to FeS2anode involved intercalation,and conversion reactions plague its applicability of sodium-ion batteries （SIBs）.Here,a significantly expedited kinetics via cation intercalation and considerably relieved stress accumulation by constructing the concave scaffold protector are approached for *** Mn2+intercalation into FeS2,a new stable Mn–FeS2was generated with distorted coordination;elevated antibonding orbital occupancy and lowed d band center to the release of more free Na+were achieved,which was further encapsulated by hollow bowl-like carbon spheres （BC）This cation intercalation and concave morphology strategies confer Mn–FeS2@BC significantly enhanced electron ion transport kinetics via reversed electron transfer to FeS2fast desolvation kinetics,and evidently depressed structural deformation during Na+insertion and ***,Mn–FeS2@BC delivers the longevity and stable Na+storage capacity in both half and full cell ***,Mn–FeS2@BC also displays excellen adaptability in a wider temperature *** work proposes new views into the deep regulation of electrochemical performance of transition metal anodes via intercalation chemistry and concave engineering.

关键词： Concave engineering FeS2 Intercalation chemistry Sodium capture

Spherical Polyelectrolyte Brush Nanoreactor:Preparation of Hollow TiO_(2) Nanospheres and Characterization by Small Angle X-Ray Scattering

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Chinese Journal of Polymer Science 2024年第9期42卷 1393-1400,I0009页

作者： Yu-Hua Zhang zi-Yu Zhang Xin Liu En-Guang Ma Jiang-Tao guo Li Li Xu-Hong guo State Key Laboratory of Chemical Engineering East China University of Science and TechnologyShanghai200237China Shandong Provincial Key Laboratory of Monocrystalline Silicon Semiconductor Materials and Technology College of Chemistry and Chemical EngineeringDezhou UniversityDezhou253023China Institute of Bast Fiber Crops&Center of Southern Economic Crops Chinese Academy of Agricultural SciencesChangsha410205China

Titanium dioxide(TiO_(2))hollow nanoparticles present significant potential for photocatalytic applications while their straightforward preparation with precise structure control is still *** work reports the approach to preparing tunable hollow TiO_(2) nanospheres by utilization of spherical polyelectrolyte brushes(SPB)as nanoreactors and *** the preparation,the evolution of the structure was characterized by small angle X-ray scattering(SAXS),and in combination with dynamic light scattering and transmission electron *** formation of TiO_(2) shell within the brush(SPB@TiO_(2))is confirmed by the significant increase of the electron density,and its internal structure has been analyzed by fitting SAXS data,which can be influenced by Titanium precursors and ammonia *** calcining SPB@TiO_(2) in a muffle furnace,hollow TiO_(2) nanospheres are produced,and their transition to the anatase crystal form is triggered,as confirmed by X-ray diffraction *** the advantages of their hollow structure,these TiO_(2) nanospheres exhibit exceptional catalytic degradation efficiency of methylene blue(MB),tetracycline(TC),and 2,4-dichlorophenoxyacetic acid(2,4-D),and also demonstrate excellent recyclability.

关键词： Spherical polyelectrolyte brush Nanoreactor Hollow titanium dioxide X-ray scattering

Investigation of Maxima Assumptions in Modelling Tropical Cyclone- Induced Hazards in the South China Sea

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China Ocean Engineering 2024年第3期38卷 491-504页

作者： WEN Ze-guo WANG fu-ming WAN Jing YANG Fan School of Civil Engineering Sun Yat-sen University&Southern Marine Science and Engineering Guangdong Laboratory(Zhuhai)Zhuhai 519082China Guangdong Academy of Safety Science and Technology Guangzhou 510060China Guangdong Key Laboratory of Oceanic Civil Engineering Guangzhou 510275China Advanced Energy Science and Technology Guangdong Laboratory(Yangjiang Offshore Wind Energy Laboratory) Yangjiang 529500China

The present study aims to examine the suitability of two commonly used assumptions that simplify modelling metoceanconditions for designing offshore wind turbines in the South China Sea (SCS). The first assumption assumes thatjoint N-year extreme wind and wave events can be independently estimated and subsequently combined. The secondone assumes peak wind and waves can be modelled as occurring simultaneously during a tropical cyclone (TC) *** better understand the potential TC activity, a set of 10000 years synthetic TC events are generated. The wind fieldmodel and the Mike 21 spectral wave model are employed to model the TC-induced hazards. Subsequently, theeffect of the assumptions is evaluated by analyzing the peak structural response of both monopile and semisubmersibleoffshore wind turbines during TC events. The results demonstrate that the examined assumptions are generally *** assessing the implications of these assumptions, valuable insights are obtained, which can inform andimprove the modelling of TC-induced hazards in the SCS region.

关键词： tropical cyclone numerical wave modelling hazards offshore wind turbines structural response