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Formation mechanism of interface reaction layer between microporous magnesia refractories and molten steel and its effect on steel cleanliness

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Journal of Iron and Steel Research International 2023年第9期30卷 1743-1754页

作者： Wen-wen Zhang Wan Zheng Wen Yan Guang-qiang Li The State Key Laboratory of Refractories and Metallurgy Wuhan University of Science and TechnologyWuhan 430081HubeiChina Key Laboratory for Ferrous Metallurgy and Resources Utilization of Ministry of Education Wuhan University of Science and TechnologyWuhan 430081HubeiChina Hubei Provincial Key Laboratory for New Process of Ironmaking and Steelmaking Wuhan University of Science and TechnologyWuhan 430081HubeiChina

The ceramic filter in continuous casting tundish can effectively improve the cleanliness of high-performance steel by regulating tundish flow field to promote the removal of inclusions and adsorbing or blocking fine inclusions in the molten steel into the *** interaction between microporous magnesia refractories used as tundish filter and molten interstitial-free(IF)steel at 1873 K was investigated to reveal the formation mechanism of their interface layer and its effect on steel cleanliness by laboratory research and thermodynamic *** results show that the magnesium–aluminum spinel layer at the interface between the molten IF steel and the microporous magnesia refractories is formed mainly by the reaction of MgO in the refractory with the[Al]and[O]in the molten steel,significantly reducing the total O content,the size and amount of inclusions of the molten *** addition,the interparticle phases of microporous magnesia refractories at high temperature can adsorb Al_(2)O_(3) and TiO_(2) inclusions in the molten steel into interparticle channels of the refractories to form high melting point spinel,impeding the further penetration of the molten *** a result,the consecutive interface layer of high melting point spinel between microporous magnesia refractories and molten steel can improve the cleanliness of the molten steel by adsorbing inclusions in the molten steel and avoid the direct dissolution of refractories of the tundish ceramic filter immersed in the molten steel,increasing their service life.

关键词： Tundish metallurgy Microporous magnesia refractory Interstitial-free steel Formation mechanism Interface reaction layer Inclusion removal

Covalent organic frameworks catalyzed by organic Lewis acid

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Science China Chemistry 2022年第7期65卷 1315-1320页

作者： Xiangqian Shi Lezhi Yi Hexiang Deng College of Chemistry and Molecular Sciences Wuhan UniversityWuhan 430072China Hubei Yangtze Memory Laboratories Wuhan 430205China Key Laboratory of Biomedical Polymers-Ministry of Education College of Chemistry and Molecular SciencesWuhan UniversityWuhan 430072China

We report the synthesis of covalent organic framework(COF)crystals with organic Lewis acid instead of the conventional use of Br?nsted acid or inorganic Lewis ***,tris(pentafluorophenyl)borane was applied for the growth of seven imine COFs:TAPB-PDA-,TAPB-2,5-DMTA-,TAPB-2,3-DMTA-,TAPT-PDA-,TAPT-2,5-DMTA-,TAPT-2,3-DMTA-COF with hcb topology and varied in functional groups,as well as a new one,COF-820,with sql *** these COFs were obtained at room *** high crystallinity and porosity demonstrate the versatility of the organic Lewis acid as a *** organic Lewis acid was found critical for the production of COF-820,while its absence resulted in the formation of a different COF,4PE-1P-COF,with kgm topology using the same building *** steric effect,typical for organic catalysts,provides a new way to regulate the topology of COFs and their future design.

关键词： covalent organic framework organic lewis acid tris(pentafluorophenyl)borane topology regulation

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Studies on Microwave-assisted Ring-opening Polymerization and Property of Poly(9-phenyl-2,4,8,10-tetraoxaspiro-[5,5]undcane-3-one)

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Chinese Journal of Polymer Science 2016年第11期34卷 1330-1338页

作者： Fan Liu Li-li Mei Zhi-lin Tan 鄢国平 Jun-fang Guo Qiao Zhang Hui Liu Jun Yang School of Material Science and Engineering Wuhan Institute of TechnologyWuhan 430074China

Poly（9-phenyl-2,4,8,10-tetraoxaspiro-[5,5]undcane-3-one）（PPTC） was synthesized by the microwave-assisted ring-opening polymerization （MROP） of a six-membered cyclic carbonate monomer 9-phenyl-2,4,8,10-tetraoxaspiro- [5,5]undcane-3-one （PTC） with tin（Ⅱ） 2-ethylhexanoate （Sn（Oct）2） or aluminum isopropoxide （Al（OiPr）3） as the catalysts. The obtained polycarbonates were further reduced by apalladium/carbonate catalyst （10% Pd/C） to afford partly deprotected polycarbonates containing hydroxyl groups （HPPTC）. These two types of polycarbonates were characterized by ^1H-NMR, Fourier transform infrared spectroscopy （FTIR）, UV, gel permeation chromatography （GPC）, differential scanning calorimetry （DSC）, and automatic contact-angle measurements. The influence of the feed molar ratio of monomer-to-catalyst, the microwave irradiation power and the reaction time on the polymerization was also studied. The experimental results showed that HPPTC possessed significantly higher hydrophilicity and water absorption rate than PPTC.

关键词： Biodegradable polycarbonate Microwave-assisted polymerization Ring-opening polymerization Hydrophilicity.

Integrated sensor based on acoustics-electricity-mechanics coupling effect for wireless passive gas detection

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Nano Research 2023年第2期16卷 3130-3141页

作者： Licheng Zhou Bohui Zhai Zhixiang Hu Mingqi Zhang Long Li Xiangxin Wang Guangzu Zhang Jingting Luo Honglang Li Bingbing Chen Shenglin Jiang Hua-Yao Li Huan Liu School of Optical and Electronic Information Wuhan National Laboratory for OptoelectronicsOptics Valley LaboratoryHuazhong University of Science and TechnologyWuhan 430074China Shenzhen Huazhong university of Science and Technology Research Institute Shenzhen Virtual University ParkShenzhen 518000China Key Laboratory of Optoelectronic Devices and Systems College of Physics and Optoelectronic EngineeringShenzhen UniversityShenzhen 518060China CAS Center for Excellence in Nanoscience National Center for Nanoscience and TechnologyBeijing 100190China School of Energy Science and Engineering Nanjing Tech UniversityNanjing 211816China

Integrated sensor combines multiple sensor functions into a single unit,which has the advantages of miniaturization and better application ***,limited by the sensing platforms of the sensor and the selectivity of the sensitive film,there are still challenges to realize multi-component gas detection in one ***,a principle integration method is proposed to achieve the multi-component gas detection based on the acoustics-electricity-mechanics coupling *** electrical and mechanical properties of the Bi_(2)S_(3)nanobelts materials in different atmospheres indicate the possibility of realizing the principle *** the same time,the surface acoustic wave(SAW)sensor as a multivariable physical transducer can sense both electrical and mechanical *** exposure to 10 ppm NO_(2),NH_(3),and their mixtures,the integrated SAW gas sensor shows a 4.5 kHz positive frequency shift(acoustoelectric effect),an 11 kHz negative frequency shift(mechanics effects),and a reduced 4 kHz negative frequency shift(acoustics-electricity-mechanics coupling effect),***,we realize wireless passive detection of NO_(2)and NH_(3)based on the SAW *** work provides valuable insights that can serve as a guide to the design and fabrication of single sensors offering multi-component gas detection via different gas sensing mechanisms.

关键词： integrated gas sensor bismuth sulfide surface acoustic wave coupling effect wireless passive

Relationship between contact size and static friction:An approach for rigid crystalline surfaces

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Friction 2021年第3期9卷 502-512页

作者： Hao CHEN Xinlei GAO School of Chemical and Environmental Engineering Wuhan Polytechnic UniversityWuhan 430023China

Relationship between contact size(A)and static friction(f)has been studied for rigid crystalline *** built a series of systems with two identical surfaces but different orientations and investigated the effects of the size and shape of the contact area on static *** these systems,there are numerous nontrivial commensurate *** results confirmed that the relationship between A and f was determined by both commensurability and shape of the *** commensurate contacts,f∝A independent of the *** incommensurate contacts,generally f∝A^(0) for regular shapes or f∝A^(1/4) for irregular shapes;however,in very few cases of regular shapes,f∝A^(1/2).Moreover,in above systems,commensurability of a contact can be easily changed by a perturbation of the misfit ***,if the perturbation caused by the lateral force and the deformation of the surface are considered(as is the case in real systems),further research is necessary.

关键词： static friction contact size numeric simulation rigid body

Rastall gravity:accretion disk image in the context of radiation fields and visual transformations compared to Reissner-Nordström black hole

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Chinese Physics C 2024年第4期48卷 174-182页

作者：黄宇翔郭森梁宇崔宇昊蒋青权林恺 School of Physics and Astronomy China West Normal UniversityNanchong 637000China Guangxi Key Laboratory for Relativistic Astrophysics School of Physical Science and TechnologyGuangxi UniversityNanning 530004China Hubei Subsurface Multi-scale Imaging Key Laboratory Institute of Geophysics and GeomaticsChina University of GeosciencesWuhan 430074China

In this study,we investigated the astronomical implications of Rastall gravity,particularly its behavior amidst a radiation field compared to Reissner-Nordström(RN)black *** found a crucial correlation between the dynamics of the accretion disk and the parameters Q and Nr,which properly reflect the influence of spacetime metrics on the disk’s *** electric charge Q causes contraction in the disk’s orbit due to enhanced gravitational effects,while higher Nr values lead to outward expansion,influenced by the attributes of the radiation ***,the charged black holes surrounded by radiation fields exhibit distinct visual disparities from RN black *** decreases and expansion occurs within the innermost stable circular orbit of the accretion disk with rising Nr *** study also reveals the process by which the accretion disk transitions from a conventional disk-like structure to a hat-like form at different observation angles,with the redshift effect gradually ***,the results of the considered Rastall gravity radiation field are consistent with the constraints of the gravitational lensing of the host galaxy on Rastall gravity parameters,thereby enhancing the consistency between theoretical predictions and actual observations.

关键词： Rastall theory optical appearance thin accretion disk

Selective oxidation of benzyl alcohols to benzoic acid catalyzed by eco-friendly cobalt thioporphyrazine catalyst supported on silica-coated magnetic nanospheres

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Journal of Environmental Sciences 2017年第10期29卷 84-90页

作者： Huan Li Lan Cao Changjun Yang Zhehui Zhang Bingguang Zhang Kejian Deng Key Laboratory of Catalysis and Material Sciences of the State Ethnic Affairs Commission & Ministry of Education College of Chemistry and Material Science South-Central University For Nationalities

A novel magnetically recoverable thioporphyrazine catalyst（CoPz（S-Bu）8/SiO2@Fe3O4） was prepared by immobilization of the cobalt octkis（butylthio） porphyrazine complex（CoPz（S-Bu）8） on silica-coated magnetic nanospheres（SiO2@Fe3O4）. The composite CoPz（S-Bu）8/SiO2@Fe3O4appeared to be an active catalyst in the oxidation of benzyl alcohol in aqueous solution using hydrogen peroxide（H2O2） as oxidant under Xe-lamp irradiation,with 36.4% conversion of benzyl alcohol, about 99% selectivity for benzoic acid and turnover number（TON） of 61.7 at ambient temperature. The biomimetic catalyst CoPz（S-Bu）8was supported on the magnetic carrier SiO2@Fe3O4 so as to suspend it in aqueous solution to react with substrates, utilizing its lipophilicity. Meanwhile the CoPz（S-Bu）8can use its unique advantages to control the selectivity of photocatalytic oxidation without the substrate being subjected to deep oxidation. The influence of various reaction parameters on the conversion rate of benzyl alcohol and selectivity of benzoic acid was investigated in detail. Moreover, photocatalytic oxidation of substituted benzyl alcohols was obtained with high conversion and excellent selectivity, specifically conversion close to 70%, selectivity close to 100% and TON of 113.6 for para-position electron-donating groups. The selectivity and eco-friendliness of the biomimetic photocatalyst give it great potential for practical applications.

关键词： Cobalt thioporphyrazine Magnetic nanospheres Composite catalyst Photocatalytic oxidation Substituted benzyl alcohol Benzoic acid

Effect of Conformation on UV-Vis Absorption Spectra of Disazo Reactive Red Dyes

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wuhan university Journal of Natural Sciences 2016年第6期21卷 512-518页

作者： XIE Xiaomei LI Xiaolei LUO Hanhan LEI Kelin LI Wei School of Chemical Engineering and Food Science Hubei University of Arts and Science College of Chemistry and Chemical Engineering Wuhan Textile University

In this study,twenty disazo reactive red dyes with J acid as coupling components were selected,and their ground state geometry were studied with BLYP functional and TZVP basis set. The UV-vis absorption spectra were calculated by time-dependent density functional theory（TDDFT） employing B3 LYP and PBE0 hybrid functionals and TZVP basis set,and the absolute mean errors are 0.094 e V and 0.133 e V for B3 LYP and PBE0,respectively. From the comparison of the calculated λ_（max） of the three conformations of disazo reactive red dye,cis-,trans-,and azo,with that of experimental one,we find out that conformation plays an important role on UV-Vis absorption. Dyes 6 and 8 exist in azo conformation rather than in cis-conformation. ＂Hole-electron＂ distribution analysis reveals that although these λ_（max） arises from different electron transitions,these electron excitations have the same character of local excitation（LE）.

关键词： dye UV-Vis absorption spectrum time-dependent density functional theory(TDDFT)

La-doped PMN-PT transparent ceramics with ultra-high electro-optic effect and its application in optical devices

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Journal of Advanced Ceramics 2023年第7期12卷 1441-1453页

作者： Ming Hu Zhongcan Chang Nan Nie Zhujun Wan Wen Dong Qiuyun Fu School of Integrated Circuits Wuhan National Laboratory for Optoelectronics&Optical Valley LaboratoryHuazhong University of Science and TechnologyWuhan 430074China Research Institute of Huazhong university of Science and Technology in Shenzhen Shenzhen 518000China National Engineering Research Center of Next Generation Internet Access-system Wuhan 430074China

Transparent electro-optic(EO)ceramics of La-doped 0.75Pb(Mg_(1/3)Nb_(2/3))O_(3)-0.25PbTiO_(3)(0.75PMN-0.25PT)were prepared *** transparency of 69%in the near-infrared(IR)wavelength(1550 nm)was achieved at 2 mo1%La doping,meanwhile it shows an extremely high quadratic EO coeficient of 45.4×10^(-16)m^(2)·V^(-2),which s indispensable for applications in EO *** distribution of a polar nanodomain structure of the samples experiences disorder-order-disorder evolution in a La doping *** is found that a parallelly-stacked polar nanodomain structure with an easier and faster polarization switching in the 2 mol%La-doped sample suggests that an ordering distribution of polar nanoregions would be critical to inducing large EO effect,transparency,and piezoelectric response.A triple-cavity tunable optical filter(TOF)with a single transmission peak and a tuning voltage below 30 V in a tuning range of 190-197 THz was designed based on our *** work is believed to bridge the relationship among doping-engineering,EO properties,and polarization behavior,which would guide the further optimization of transparent EO ceramics.

关键词： Pb(Mg_(1/3)Nb_(2/3))O_(3)-PbTiO_(3)(PMN-PT)electro-optic(EO)ceramics transmittance domain reversal polarization tunable optical filter(TOF)