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Impact of Hard Segment Structures on Fatigue Threshold of Casting Polyurethane Using Cutting Method

Chinese Journal of Polymer science 2025年第2期43卷 303-315页

作者： Guang-Zhi Jin Le-Hang Chen Yu-Zhen Gong Peng Li Run-Guo Wang Fan-Zhu Li Yong-Lai Lu State Key Laboratory of Organic-Inorganic Composites Beijing University of Chemical TechnologyBeijing100029China Engineering Research Center of Elastomer Materials Energy Conservation and Resources Ministry of EducationBeijing100029China Key Laboratory of Carbon Fiber and Functional polymers Beijing University of Chemical TechnologyBeijing100029China Center of Advanced Elastomer Materials College of Material Science and EngineeringBeijing University of Chemical TechnologyBeijing100029China

The fatigue resistance of casting polyurethane(CPU)is crucial in various sectors,such as construction,healthcare,and the automotive *** its importance,no studies have reported on the fatigue threshold of *** study employed an advanced Intrinsic Strength Analyzer(ISA)to evaluate the fatigue threshold of CPUs,systematically exploring the effects of three types of isocyanates(PPDI,NDI,TDI)that contribute to hard segment structures based on the cutting *** multiple advanced characterization techniques(XRD,TEM,DSC,AFM),the results indicate that PPDI-based polyurethane exhibits the highest fatigue threshold(182.89 J/m^(2))due to a highest phase separation and a densely packed spherulitic structure,although the hydrogen bonding degree is the lowest(48.3%).Conversely,NDI-based polyurethane,despite having the high hydrogen bonding degree(53.6%),exhibits moderate fatigue performance(122.52 J/m^(2)),likely due to a more scattered ***-based polyurethane,with the highest hydrogen bonding degree(59.1%)but absence of spherulitic structure,shows the lowest fatigue threshold(46.43 J/m^(2)).Compared to common rubbers(NR,NBR,EPDM,BR),the superior fatigue performance of CPU is attributed to its well-organized microstructure,polyurethane possesses a higher fatigue threshold due to its high phase separation degree and orderly and dense spherulitic structure which enhances energy dissipation and reduces crack propagation.

关键词： Casting polyurethane Fatigue threshold Cutting method Hard segment structures materials characterization

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Poly(alkyl-biphenyl pyridinium)anion exchange membranes with a hydrophobic side chain for mono-/divalent anion separation

Industrial Chemistry & Materials

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Industrial Chemistry & materials 2023年第1期1卷 129-139页

作者： Hongxin Yang Noor Ul Afsar Qian Chen Xiaolin Ge Xingya Li Liang Ge Tongwen Xu Anhui Provincial Engineering Laboratory of Functional Membrane Materials and Technology Department of Applied ChemistrySchool of Chemistry and Materials ScienceUniversity of Science and Technology of ChinaHefei 230026PR China Applied Engineering Technology Research Center for Functional Membranes Institute of Advanced TechnologyUniversity of Science and Technology of ChinaHefei230088PR China

A series of poly(alkyl-biphenyl pyridinium)anion exchange membranes(AEMs)with a hydrophobic side chain were prepared for mono-/divalent anion separation using electrodialysis(ED).A poly(alkyl-biphenyl pyridinium)polymer was synthesized via superacid-catalyzed polymerization,and then quaternization was conducted using Menshutkin reactions with *** obtained quaternized product had excellent solubility in common organic solvents,making it flexible to form homogeneous membranes by a solution casting *** introduction of a hydrophobic side chain resulted in a microphase separation structure in the membrane,which is favorable to the active transport of Cl−(higher Cl−flux of up to 3.37 mol m−2 h−1 at a 10 mA cm−2 current density)compared with that of SO42−ions giving a high permselectivity of 11.9 in a mixed salt(NaCl/Na2SO4)*** addition,the prepared membrane exhibited excellent alkaline stability in successive ED *** showed an OH−flux of up to 3.6 mol m−2 h−1 with a permselectivity of 361.2 between OH−and WO42−,which is much higher than that of Neosepta ACS *** ED results manifest that the poly(alkyl-biphenyl pyridinium)AEMs can be promising candidates for practical mono-/divalent anion separation in industry.

关键词： Superacid-catalyzed polymerization Anion exchange membrane Mono-/divalent anion separation Electrodialysis Permselectivity

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Abnormal low-field M-type magnetoresistance in hexagonal noncollinear ferromagnetic MnFeGe alloy

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Rare Metals 2022年第8期41卷 2680-2687页

作者： Jia-Xuan Tang Pei-Hao Wang Yu-Rong You Ya-Dong Wang Zhan Xu Zhi-Peng Hou Hong-Guo Zhang Gui-Zhou Xu Feng Xu MIIT Key Laboratory of Advanced Metallic and Internetallic Materials Technology School of Materials Science and EngineeringNanjing University of Science and TechnologyNanjing210094China Guangdong Provincial Key Laboratory of Quantum Engineering and Quantum Materials South China Academy of Advanced OptoelectronicsSouth China Normal UniversityGuangzhou510006China Faculty of Materials and Manufacturing Key Laboratory of Advanced Functional MaterialsMinistry of Education of ChinaBeijing University of TechnologyBeijing100124China

The new magnetic degree of freedom provided by the noncollinear structure plays an important role in the development of spintronic *** this work,we conducted a systematic study on the magnetic and electrical transport properties of the hexagonal noncollinear ferromagnetic MnFeGe *** Hall effect and moderate magnetoresistance(MR)were observed below the Curie temperature(~200 K)of MnFeGe,in both bulk and thin-film ***,the perpendicular MR in all samples firstly grows,then quasi-linearly descends with magnetic field increasing,making an irregular M-type MR in the low-field *** is speculated that the abnormal MR is related to the magnetic domain change,and combined with micromagnetic simulations,the labyrinth domain and sparse bubble formation are verified to exist in *** work offers an understanding of the lowfield-positive MR in a ferromagnet,as well as raises the possibility of magnetic bubble formation in this noncollinear system.

关键词： M-type magnetoresistance Noncollinear MnFeGe Skyrmionic bubbles

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Metalphthalocyanine frameworks grown on TiO_(2)nanotubes for synergistically and efficiently electrocatalyzing urea production from CO_(2)and nitrate

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science China Chemistry 2023年第5期66卷 1417-1424页

作者： Ning Li Hui Gao Zhixin Liu Qianjun Zhi Bowen Li Lei Gong Baotong Chen Tao Yang Kang Wang Peng Jin Jianzhuang Jiang Beijing Advanced Innovation Center for Materials Genome Engineering Beijing Key Laboratory for Science and Application of Functional Molecular and Crystalline MaterialsDepartment of Chemistry and Chemical EngineeringSchool of Chemistry and Biological EngineeringUniversity of Science and Technology BeijingBeijing 100083China School of Materials Science and Engineering Hebei University of TechnologyTianjin 300130China Innovation Research Institute for Carbon Neutrality University of Science and Technology BeijingBeijing 100083China

Electrocatalytic synthesis of urea from CO_(2)and NO_(3)^(-)under ambient conditions provides an appealing alternative to the traditional energy-intensive urea synthetic *** active and selective electrocatalysts for efficient urea production are therefore urgently desired owing to the unsatisfactory performance of the thus far reported ***,a phthalocyaninebased(Pc-based)covalent organic framework(COF),namely Co Pc-COF,fabricated from the nucleophilic substitution reaction of hexadecafluorophthalocyaninato cobalt with octahydroxylphthalocyanine cobalt,in situ grew on the surface of multilayered Ti O_(2)nanotubes(NTs),generating the Co Pc-COF@Ti O_(2)NTs *** X-ray diffraction analysis in combination with electron microscopy measurements discloses the uniform coating of crystalline Co Pc-COF on the multilayered Ti O_(2)NTs in Co Pc-COF@Ti O_(2)***,electrochemical tests reveal the superior electrocatalytic activity of Co Pc-COF@Ti O_(2)NTs towards urea production from CO_(2)and NO3-with a record-high yield of 1,205μg h^(-1)cm^(-2)and an outstanding Faraday efficiency of 49%at-0.6 V versus reversible hydrogen electrode due to the significant synergistic catalysis *** situ attenuated total reflection infrared spectroscopic investigation and theoretical calculations unveil the efficient C–N coupling reaction between*CO intermediate derived from CO_(2)on Co Pc moieties and*NH2intermediate formed from NO_(3)^(-)on Ti O_(2)NTs during the urea formation process over Co Pc-COF@Ti O_(2)*** work should be helpful towards designing and fabricating high-performance electrocatalysts for sustainable synthesis of urea through efficient synergistic effect of multiactive centers.

关键词： covalent organic frameworks phthalocyanine TiO_(2) electrocatalytic urea synthesis C–N bond coupling

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Bifunctional optical probe based on La_(3)Mg_(2)SbO_(9):Mn^(4+)phosphors for temperature and pressure sensing

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Journal of materials science & technology 2024年第27期194卷 98-109页

作者： Zhanglin Chen Songmo Du Fei Li Shijia Zhang Shuo Zhao Zhaobo Tian Jie Zhang Xuanyi Yuan Guanghua Liu Kexin Chen State Key Laboratory of New Ceramics&Fine Processing School of Materials Science and EngineeringTsinghua UniversityBeijing 100084China School of Microelectronics Southern University of Science and TechnologyShenzhen 518055China Advanced Ceramics and Structures Center Yongjiang LaboratoryNingbo 315021China Beijing Key Laboratory of Optoelectronic Functional Materials&Micro-nano Devices Department of PhysicsRenmin University of ChinaBeijing 100872China

Photoluminescent materials,serving as optical probes,constitute a significant medium for reliable re-mote sensing of fundamental state parameters such as temperature and ***,we report a novel Mn^(4+)-activated perovskite-type La_(3) Mg2 SbO9 phosphor(LMS:Mn^(4+))for bifunctional application in both thermometry and *** excitation with 341 nm,LMS:Mn^(4+)(0.7%Mn^(4+))emits a bright narrow-band red light peaking at 705 nm with an FWHM(full width at half maximum)of 32 *** a thermometer,when the temperature surpasses 298 K,non-radiative transitions from the ^(2)Eg excited state lead to a sharp decrease in decay lifetimes with increasing *** allows for lifetime-based luminescence thermometry with a relative sensitivity of 2.52%K^(−1) at 391 ***,LMS:Mn^(4+)was processed into a temperature-sensing coating and its non-contact thermometry functionality was *** manometry applications,the LMS:Mn^(4+)probe experiences substantial pressure-dependent redshift with a sensitivity of 1.20 nm GPa^(−1) in the testing range of 9.48 GPa,which is about 3.3 times that of conventional ruby ***,its FWHM consistently remains below 37 nm,which con-tributes to a high reliability of pressure *** above results indicate that the LMS:Mn^(4+)constitutes a promising bifunctional luminescence probe material in thermometry and manometry.

关键词： Perovskite Phosphors Thermometry Manometry

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Platinum modification of metallic cobalt defect sites for efficient electrocatalytic oxidation of 5-hydroxymethylfurfural

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Journal of Energy Chemistry 2025年第2期101卷 463-473,I0010页

作者： Haoyu Zhan Baixue Cheng Yankun Lu Danning Xing Xingshuai Lv Huining Huang Thomas Frauenheim Tao Wang Peng Zhou State Key Laboratory of Bio-fibers and Eco-textiles College of Materials Science and EngineeringCollaborative Innovation Center of Shandong Marine Biobased Fibers and Ecological TextilesInstitute of Marine Biobased MaterialsQingdao UniversityQingdao 266071ShandongChina Shandong Institute of Advanced Technology Jinan 250100ShandongChina College of Chemistry and Chemical Engineering Ocean University of ChinaQingdao 266100ShandongChina Tianjin Key Laboratory of Advanced Functional Porous Materials Institute for New Energy Materials & Low-Carbon TechnologiesSchoolof Materials Science and Engineering Tianjin University of TechnologyTianjin 300384China School of Science Constructor UniversityBremen 28759Germany Beijing Computational Science Research Center Beijing 100193China College of Chemistry and Molecular Engineering Qingdao University of Science and TechnologyQingdao 266042ShandongChina

Co_(3)O_(4)possesses both direct and indirect oxidation effects and is considered as a promising catalyst for the oxidation of 5-hydroxymethylfurfural(HMF).However,the enrichment and activation effects of Co_(3)O_(4)on OH-and HMF are weak,which limits its further *** defect engineering can regulate the electronic structure,optimize the adsorption of intermediates,and improve the catalytic activity by breaking the symmetry of the material,which is rarely involved in the upgrading of *** this work,we prepare Co_(3)O_(4)with metal defects and load the precious metal platinum at the defect sites(PtVco).The results of in-situ characterizatio ns,electrochemical measurements,and theoretical calculations indicate that the reduction of Co-Co coordination number and the formation of Pt-Co bond induce the decrease of electron filling in the antibonding orbitals of Co *** resulting upward shift of the d-band center of Co combined with the characteristic adsorption of Pt species synergically enhances the enrichment and activation of organic molecules and OH species,thus exhibiting excellent HMF oxidation activity(including a lower onset potential(1.14 V)and 19 times higher current density than pure Co_(3)O_(4)at 1.35 V).In summary,this work explores the adsorption enhancement mechanism of metal defect sites modified by precious metal in detail,provides a new option for improving the HMF oxidation activity of cobalt-based materials,broadens the application field of metal defect based materials,and gives an innovative guidance for the functional utilization of metal defect sites in biomass conversion.

关键词： Electrocatalysis Biomass upgrading Metallic defect Coordination environment Adsorption enhancement

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In situ preparation of Ag@AgCl/Bio-veins composites and their photocatalytic activity and recyclability

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Frontiers of Chemical science and Engineering 2023年第7期17卷 906-917页

作者： Min Zou Chao Tan Zhengqiu Yuan Ming Wu Jian Jian Lei Zhang Yan Zhang Zhou Ma Hu Zhou School of Resource&Environment and Safety Engineering Hunan University of Science and TechnologyXiangtan 411201China Key Laboratory of Theoretical Organic Chemistry and Functional Molecules Ministry of EducationFunctional Film Materials Engineering Research Center of Hunan ProvinceHunan Provincial Key Laboratory of Advanced Materials for New Energy Storage and ConversionSchool of Chemistry and Chemical EngineeringHunan University of Science and TechnologyXiangtan 411201China School of Information and Electrical Engineering Hunan University of Science and TechnologyXiangtan 411201China

The industrial application of nano-photocatalysts in wastewater treatment has been severely restricted for a long time due to their difficult separation,poor reusability,and low *** this work,a facile strategy was proposed to enhance the photocatalytic activity and recovery performance of Ag@AgCl *** veins(Bio-veins)with a unique 3D porous construction were used as carriers for the in-situ growth of Ag@AgCl *** electron microscopy results showed that the Ag@AgCl nanoparticles were uniformly loaded on the surface and interior of the Bio-veins,and the size of the Ag@AgCl nanoparticles immobilized on the Bio-veins(50–300 nm)was significantly smaller than Ag@AgCl obtained by the co-precipitation method(1–3μm).The Bio-veins played a vital role in the photocatalysis reaction *** degradation efficiency of the Ag@AgCl/Bio-veins(CI4)was up to 3.50 times as high as pure Ag@***,the composites also exhibited excellent recyclability and stability under both visible and solar *** work provided a suitable strategy for nano-photocatalysts for practical application and may also offer new possibilities for the high-value utilization of biomass materials.

关键词： Ag@AgCl biological veins photocatalytic activity recyclability

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Meter-Scale Thin-Walled Structure with Lattice Infill for Fuel Tank Supporting Component of Satellite:Multiscale Design and Experimental Verification

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Computer Modeling in Engineering & sciences 2024年第1期138卷 201-220页

作者： Xiaoyu Zhang Huizhong Zeng Shaohui Zhang Yan Zhang Mi Xiao Liping Liu Hao Zhou Hongyou Chai Liang Gao Beijing Key Laboratory of Lightweight Multi-Functional Composite Materials and Structures Beijing Institute of TechnologyBeijing100081China Beijing Key Laboratory of Intelligent Space Robotic Systems Technology and Applications Beijing Institute of Spacecraft System EngineeringChina Academy of Space TechnologyBeijing100094China Key Laboratory of Metallurgical Equipment and Control Technology Ministry of EducationWuhan University of Science and TechnologyWuhan430081China State Key Laboratory of Digital Manufacturing Equipment and Technology Huazhong University of Science and TechnologyWuhan430074China

Lightweight thin-walled structures with lattice infill are widely desired in satellite for their high stiffness-to-weight ratio and superior buckling strength resulting fromthe sandwich *** structures can be fabricated bymetallic additive manufacturing technique,such as selective laser melting(SLM).However,the maximum dimensions of actual structures are usually in a sub-meter scale,which results in restrictions on their appliance in aerospace and other *** this work,a meter-scale thin-walled structure with lattice infill is designed for the fuel tank supporting component of the satellite by integrating a self-supporting lattice into the thickness optimization of the *** designed structure is fabricated by SLM of AlSi10Mg and cold metal transfer welding ***-static mechanical tests and vibration tests are both conducted to verify the mechanical strength of the designed large-scale lattice thin-walled *** experimental results indicate that themeter-scale thin-walled structure with lattice infill could meet the dimension and lightweight requirements of most spacecrafts.

关键词： Thin-walled structure lattice infill supporting component selective laser melting satellite

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Efficient wide-bandgap perovskite solar cells with open-circuit voltage deficit below 0.4 V via hole-selective interface engineering

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science China Chemistry 2024年第6期67卷 2102-2110页

作者： Xiaoyu Ji Shuo Zhang Furong Yu Huidong Zhang Liqing Zhan Yue Hu Wei-Hong Zhu Yongzhen Wu Key Laboratory for Advanced Materials and Joint International Research Laboratory of Precision Chemistry and Molecular Engineering Shanghai Key Laboratory of Functional Materials ChemistryFrontiers Science Center for Materiobiology and Dynamic ChemistryInstitute of Fine ChemicalsSchool of Chemistry and Molecular EngineeringEast China University of Science and TechnologyShanghai200237China School of Chemistry University of EdinburghKing’s BuildingsEdinburghEH93FJUK

Wide-bandgap mixed-halide perovskite solar cells(WBG-PSCs)are promising top cells for efficient tandem photovoltaics to achieve high power conversion efficiency(PCE)at low ***,the open-circuit voltage(V_(OC))of WBG-PSCs is still unsatisfactory as the V_(OC)-deficit is generally larger than 0.45 ***,we report a buried interface engineering strategy that substantially improves the V_(OC)of WBG-PSCs by inserting amphiphilic molecular hole-selective materials featuring with a cyanovinyl phosphonic acid(CPA)anchoring group between the perovskite and *** assembly and redistribution of CPA-based amphiphilic molecules at the perovskite-substrate buried interface not only promotes the growth of a low-defect crystalline perovskite thin film,but also suppresses the photo-induced halide phase *** energy level alignment between wide-bandgap perovskite and the hole-selective layer is further improved by modulating the substituents on the triphenylamine donor moiety(methoxyls for MPA-CPA,methyls for Me PA-CPA,and bare TPA-CPA).Using a 1.68 e V bandgap perovskite,the Me PA-CPA-based devices achieved an unprecedentedly high V_(OC)of 1.29 V and PCE of 22.3%under standard AM 1.5 *** V_(OC)-deficit(<0.40 V)is the lowest value reported for *** work not only provides an effective approach to decreasing the V_(OC)-deficit of WBG-PSCs,but also confirms the importance of energy level alignment at the charge-selective layers in PSCs.

关键词： cyanovinyl phosphonic acid energy level alignment hole-selective material open-circuit voltage wide-bandgap perovskite

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CO electroreduction:What can we learn from its parent reaction,CO_(2) electroreduction?

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escience 2023年第6期3卷 1-8页

作者： Xue Ding Jie Zhang Yanguang Li Institute of Functional Nano and Soft Materials(FUNSOM) Soochow UniversitySuzhou 215123China Jiangsu Key Laboratory for Advanced Negative Carbon Technologies Soochow UniversitySuzhou 215123China Macao Institute of Materials Science and Engineering(MIMSE) MUST-SUDA Joint Research Center for Advanced Functional MaterialsMacao University of Science and TechnologyMacao999078China

The CO electroreduction reaction(CORR)represents an important piece of the decarbonization puzzle and is heavily inspired by research on the CO_(2) electroreduction reaction(CO_(2)RR).Compared to its parent reaction,CORR circumvents the(bi)carbonate issue that plagues CO_(2)RR,potentially enabling greater stability and selectivity toward C2þproducts,particularly *** its unique potential,CORR still suffers from unsatisfactory *** this perspective article,we aim to provide a concise and informative overview of CORR and its close connection with CO_(2)*** start by briefly presenting the two reactions’similarities and differences,then discussing several catalyst design *** is followed by highlights of the latest results on device integration and ***,we offer our thoughts about possible future research opportunities that could render this technology a practical reality.

关键词： CO electroreduction CO_(2)electroreduction Catalysts Devices

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