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Journal of Iron and Steel Research International 2023年第10期30卷 1939-1951页

作者： Xue-feng Bai Yan-hui Sun hui-bin Wu Collaborative Innovation Center of Steel Technology University of Science and Technology BeijingBeijing100083China

Submerged entry nozzle(SEN)clogging during continuous casting of Ti-stabilized ultra-pure ferritic stainless(Ti-UPFS)steels was systematically investigated via cross-sectional analysis and acid dissolution *** SEN deposit profile was characterized as occurring in three major layers:(1)an eroded refractory layer;(2)an initial adhesive layer comprised an Al_(2)O_(3)-ZrO_(2) composite sub-layer and a dense Al_(2)O_(3)-based deposit sub-layer;and(3)a porous multiphase deposit layer mainly consisting of MgO·Al_(2)O_(3),CaO-Al_(2)O_(3),and *** MgO·Al_(2)O_(3)-rich inclusions did not adhere directly to the eroded refractory but were entrapped during the deposit *** of inclusion characterization in the tundish revealed that the MgO·Al2O3-rich particles present in the tundish served as the primary source of clogging ***,a novel cavity-induced adhesion model by circular approximation was established to explain the effects of complex inclusion characteristics and refractory material type on adhesion force.A high number of small MgO·Al_(2)O_(3) inclusions were expected to accelerate the buildup of clogging *** the modification of MgO·Al_(2)O_(3)-rich inclusions in the size range of 2-4μm by Ca treatment was crucial to minimizing the risk of SEN clogging during the continuous casting of Ti-UPFS steels.

关键词： Ti-stabilized ultra-pure ferritic stainless steel Submerged entry nozzle clogging MgO·Al_(2)O_(3)-rich inclusion Adhesion Continuous casting

Interleukin-17 SNPs and serum levels increase ulcerative colitis risk: A metaanalysis

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World Journal of Gastroenterology 2014年第42期20卷 15899-15909页

作者： Juan li Hao Tian hui-Jun Jiang bin Han Department of Gastroenterology the Third Affiliated Hospital of Liaoning Medical University Department of Infectious Diseases the First Affiliated Hospital of Liaoning Medical University

AIM: To investigate the associations of interleukin-17 (IL-17) genetic polymorphisms and serum levels with ulcerative colitis (UC) risk.

关键词： Ulcerative colitis Interleukin-17 Polymorphism Serum Meta-analysis

Construction of Ni single-atom coordinated with doped N and S elements for mild hydrogenation of methyl acrylate to methyl propionate

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Nano Research 2025年第1期18卷 217-224页

作者： Taolue Sun Chen Jian Gang Wang hui Zhao Guoliang Zhang Zengxi li Chunshan li State Key Laboratory of Mesoscience and Engineering CAS Key Laboratory of Green Process and EngineeringBeijing Key Laboratory of Ionic Liquids Clean ProcessInstitute of Process EngineeringChinese Academy of SciencesBeijing 100190China School of Chemical Engineering University of Chinese Academy of SciencesBeijing 100049China huizhou Institute of Green Energy and Advanced Materials Huizhou 516081China Advanced Energy Science and Technology Guangdong Laboratory Huizhou 516081China

Although the nickel-based catalyst is able toexhibit comparative catalytic activity to noble metal formethyl acrylate hydrogenation,it requires strict reactioncondition,which can be improved by regulation ofcoordination *** this study,we constructed akind of Ni single-atom coordinated with N and S(Ni-NSC)through the pyrolysis of organic Ni-based precursors at600℃.The existence and fine structure of Ni single-atom were confirmed by the spherical electron microscopicobservation in combination with the X-ray absorption spectroscopy(XAS)*** addition,the catalytichydrogenation assessment suggested that the as-prepared Ni-NSC catalyst exhibited higher activity and stability than theNi/NSC supported catalyst prepared by incipient wetness impregnation *** remarkable catalytic activity was dueto the high dispersion and density of Ni single-atom and weak adsorption energy of intermediates on these Ni sites.

关键词： methyl acrylate mild hydrogenation Ni single-atom coordination environment adsorption energy

Reduced Graphene Oxide Mediated SnO_2 Nanocrystals for Enhanced Gas-sensing Properties

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Journal of Materials Science & Technology 2013年第2期29卷 157-160页

作者： Yanhong Chang Yunfeng Yao bin Wang hui Luo Tianyi li linjie Zhi School of Civil and Environmental Engineering University of Science and Technology Beijing National Center for Nanoscience and Technology School of Chemical and Biological Engineering University of Science and Technology Beijing

SnO2-reduced graphene oxide （SnO2-rGO） composites were prepared via a hydro-thermal reaction of graphene oxide （GO） and SnCI2·2H2O in the mixed solvent of ethylene glycol and water. During the redox reaction, GO was reduced to rGO while Sn2＋ was oxidized to Sn02, uniformly depositing on the surface of rGO sheets. The composites were characterized by X-ray diffraction （XRD）, scanning electron microscopy （SEM）, thermogravimetric analysis （TGA）, infrared spectra analysis （IR） and transmission electron microscopy （TEM）, respectively, and their gas sensing properties were further investigated. Compared with pure SnO2 nanoparticles, the as-prepared SnO2-rGO gas sensor and response-recovery time to ethanol and H2S at responding and low cost SnO2-rGO gas sensor could showed much better gas sensing behavior in sensitivity ow concentrations. Overall, the highly sensitive, quick- be potentially applied in environmental monitoring area.

关键词： SnO2-rGO Gas sensor Sensitivity Response-recovery time

High-temperature mechanical properties and deformation behavior of high Nb containing TiAl alloys fabricated by spark plasma sintering

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International Journal of Minerals,Metallurgy and Materials 2012年第4期19卷 354-359页

作者： Xin Lu li-hua Zhao Lang-ping Zhu bin Zhang Xuan-hui Qu State Key Laboratory for Advanced Metals end Materials School of Materials Science and Engineering University of Science and Technology Beijing Beijing 100083China School of Metallurgical and Ecological Engineering University of Science and Technology Beijing Beijing 100083 China Beijing Institute of Aeronautical Materials Beijing 100095 China

A high Nb containing TiA1 alloy was prepared from the pre-alloyed powder of Ti-45Al-8.5Nb-0.2B-0.2W-0.02Y （at%） by spark plasma sintering （SPS）. Its high-temperature mechanical properties and compressive deformation behavior were investigated in a temperature range of 700 to 1050℃ and a strain rate range of 0.002 to 0.2 s 1. The results show that the high-temperature mechanical properties of the high Nb containing TiA1 alloy are sensitive to deformation temperature and strain rate, and the sensitivity to strain rate tends to rise with the deformation temperature increasing. The hot workability of the alloy is good at temperatures higher than 900℃, while fracture occurs at lower temperatures. The flow curves of the samples compressed at or above 900℃ exhibit obvious flow softening after the peak stress. Un- der the deformation condition of 900-1050℃ and 0.002-0.2 s 1, the interrelations of peak flow stress, strain rate, and deformation tempera- ture follow the Arrhenius＇ equation modified by a hyperbolic sine function with a stress exponent of 5.99 and an apparent activation energy of 441.2 ***-1.

关键词： titanium-aluminum alloys spark plasma sintering (SPS) mechanical properties deformation activation energy

Synthesis and Characterization of Heteropoly Coordination Compounds Containing Optical ligands

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Chemical Research in Chinese Universities 2001年第1期17卷 117-120页

作者： MA hui yuan WANG Xiao guang ZHOU Bai bin ZHOU Hong li Department of Chemistry Harbin Normal University Harbin 150080P.R.China

Heteropoly coordination compounds containing optical ligands were synthesized and chracterized. Ultraviolet and ESR spectra were used to chracterize structures and test optical activity of heteropolyanions. Phase transfer for heteropolyanions wase obtained by adding equal volumes of traheptylammonium bromide (THA) in benzene under vigrous stirring until heteropolyanions transferred from the aqueous solution to the benzene solution of THA.

关键词： Keggin structure Dawson structure Optical active ligand

Study on coexistence between DCS1800 and TDD-LTE systems in multi-mode terminals

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The Journal of China Universities of Posts and Telecommunications 2014年第6期21卷 24-29页

作者： ZHENG Zhi-hui ZHAO Cheng-lin li bin TAO Hong-bo School of Telecommunication Engineering Beijing University of Posts and Telecommunications The State Radio Monitoring Center Testing Center

It＇s well known that the mobile stations will comprise a wide range of radio access technologies（RAT）, providing user with flexible and efficient access to multi-media service and high data rate communications. Although much work has been done for coexistence analysis between different systems base stations（BS）, most of them have not addressed the interference within multi-mode terminal. Hence, for filling the gap, The authors in the article present coexistence studyies of digital cellular system at 1 800 MHz（DCS1800） and time division duplex long term evolution（TDD-LTE） network in multi-mode terminal with multi-service provisioning. A new system model for coexistence was introduced and how deterministic analysis can be done within the terminal was explained. The interference evaluation model was given based on relations between reference sensitivity and signal-to-noise ratio（SNR）, which is also deduced. The system simulation methodology was provided and assumption used in simulation was given. Simulation results were shown with different system parameters. Numeric results indicate that multi-mode terminal is mainly affected by local interference. The minimum antenna isolation required for a health system operation was provided.

关键词： TDD-LTE systems coexistence analysis multi-mode terminal deterministic analysis sensitivity degradation

Tuning the Electrically Conductive Network of Grafted Nanoparticles in Polymer Nanocomposites by the Shear Field

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Chinese Journal of Polymer Science 2020年第12期38卷 1426-1434页

作者： Yan-Long Luo Xiao hui Duan bin li Xin-ling Chen Yang Yang Gao li-Qun Zhang Cllege of Science Nanjing Forestry UniversityNanjing 210037 China KeyLaboratoryof Bejing Ciy on Preparation and Pocessing of Novel Polmer Materials Bejing University ofChemical TechnologyBejing 100029China State Key Laboratory of Organic-lnorganic Composites Bejing Universityof Chemical Technology Bejing 10029China School of Chemical Engneering and Technology.Sun Yat sen University Zhuhai 519082 China

Contolling the formation of the conductive network in the polymer nanocomposites(PNCs)is very meaningful to enhance their electrical *** this work,we investigated the effect of grafted nanoparticles(NPs)on the conductive probability of PNCs in the quiescent state as well as under the shear field via a coarse grained molecular dynamics *** is found that the smallest percolation threshold is realized at the moderate grafting density,the moderate length of grafted chains or the moderate interaction between grafted chains and free *** to it,the dispersion state of NPs varies from the contact aggregation to the uniform *** analyzing the connection mode among NPs,the probabilty of NPs which connect three other ones reaches the maximum value at their moderate dispersion state which is responsible for the optimal conductive *** addition,the main cluster size is characterized to better understand the conductive network which is consistent with the percolation *** is interesting to find that the percolation threshold is smaller under the shear field than under the quiescent *** shear field induces more NPs which connect three other *** benefits the formation of the new conductive ***,the anisotropy of the conductive probability is reduced with increasing the grafting *** summary,this work provides a clear picture on how the conductive network of grafted NPs evolves under the shear field.

关键词： Conductive network Grafted nanoparticles Molecular dynamics simulation

Multilevel structured carbon film as cathode host for li-S batteries with superhigh-areal-capacity

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Nano Research 2021年第5期14卷 1273-1279页

作者： bin He Wen-Cui li Zhi-Yuan Chen Lei Shi Yu Zhang Ji-li Xia An-hui Lu State Key Laboratory of Fine Chemicals School of Chemical EngineeringDalian University of TechnologyDalian116024China

The commercialization of lithium-sulfur (li-S) battery could be accelerated by designing advanced sulfur cathode with high sulfur utilization and stable cycle life at a high sulfur loading. To allow the energy density of li-S batteries comparable to that of commercial li-ion batteries, the areal capacity of sulfur cathode should be above 4 mA·h·cm−2. In general, a high sulfur loading often causes rapid capacity fading by slowing electron/ion transport kinetics, catastrophic shuttle effect and even cracking the electrodes. To address this issue, herein, a multilevel structured carbon film is built by covering highly conductive CNTs and hollow carbon nanofiber together with carbon layer via chemical vapor deposition. The self-standing carbon film exhibits well-interweaved conductive network, hollow fibrous structure and abundant N, O co-doped active sites, which combine the merits of high electronic conductivity (1200·S·m−1), high porosity and polar characteristic in one host. Benefiting from this attractive multilevel structure, the obtained sulfur cathode based on the carbon film host shows an ultra-high areal capacity of 8.9 mA·h·cm−2 at 0.2 C with outstanding cyclability over 60 cycles. This work shed light on designing advanced sulfur host for li-S batteries with high areal capacity and high cycle stability, and might make a contribution to the commercialization of li-S batteries.

关键词： multilevel structure carbon film sulfur host conductivity areal capacity

Chain Flexibility and Connectivity:The Uniqueness of Polymer Crystallization

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Chinese Journal of Polymer Science 2023年第1期41卷 7-13页

作者： liang-bin li National Synchrotron Radiation Laboratory CAS Key Laboratory of Soft Matter ChemistryAnhui Provincial Engineering Laboratory of Advanced Functional Polymer FilmUniversity of Science and Technology of ChinaHefei230026China

Theory of polymer crystallization is listed as one of the top ten current challenges in polymer *** the uniqueness of polymer crystallization should be the first step to search for the roadmap for targeting this *** flexibility and connectivity are two peculiar characteristics of polymers,which differentiate their dynamics and structures from that of small *** uniqueness of polymer crystallization must also stem from these two peculiar characteristics,which,however,has not been attracted significant attention.A local structure order may be essential in assisting the transformation of flexible chain to rigid segment with conformational *** entanglement pressure and entanglement free energy may help to understand how entanglement affect nucleation in polymer network and why the interlamellar amorphous layer always accompany the formation of crystal *** recommendations will be given for future study.

关键词： Polymer crystallization Chain flexibility Chain connectivity Nucleation