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Rare Metals 2017年第11期36卷 858-864页

作者： Jin-Long Li Gang-Yi Cai Hua-Sheng Zhong Yong-Xin Wang Jian-Min Chen key laboratory of Marine materials and application Technologies Zhejiang Key Laboratory of Marine Materials and Protection Technologies Ningbo Institute of Materials Technologies and Engineering Chinese Academy of Sciences School of Mechanical and Electrical Engineering Henan University of Technology

TiCN coatings incorporated with Ti buffer layer were deposited on Ti6A14V alloy by arc ion plating. The carbon content in TiCN coatings was varied by controlling flow rates of C2H2 in reactive gas. The Ti/TiCN coatings have a typical structure of columnar crystal with a total thickness of about 2 pro. The elements of Ti, C and N are present as TiN and TiC in TiCN coatings. A little free carbon appears with carbon content increasing in TiCN coatings. For the TiCN coatings, the hardness, friction coefficient and wear rate decrease with the increase in carbon content. In seawater, both friction coefficient and wear rate have an obvious decrease at lower carbon content compared with those in atmosphere. However, the friction coefficient and wear rate only have a slight decrease, while the carbon content reaches or exceeds 10 at% in Ti/TiCN coatings.

关键词： Ti/TiCN coatings Arc ion plating Hardness Seawater Wear

Recent progress on photoactive nonprecious transition-metal complexes

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Science China Chemistry 2025年第1期 46-95页

作者： Zhong-Liang Gong Hong-Jie Zhang Yan Cheng Jianxun Liu Yuhan Ai Yaqin Li Zhihui Feng Qiong Zhang Shaolong Gong Yong Chen Chang-Jiang Yao Yuan-Yuan Zhu Liang-Jin Xu Yu-Wu Zhong CAS key laboratory of Photochemistry Institute of Chemistry Chinese Academy of Sciences State key laboratory of Structural Cemistry Fujian Institute of Research on the Structure of Matter Chinese Academy of Sciences School of Chemistry and Chemical Engineering Anhui Key Laboratory of Advanced Catalytic Materials and Reaction EngineeringHefei University of Technology State key laboratory of Explosion Science and Safety Protection School of Mechatronical Engineering Beijing Institute of Technology College of Chemistry and Molecular Sciences Hubei Key Lab on Organic and Polymeric Optoelectronic Materials Wuhan University School of Chemistry and Chemical Engineering Anhui University key laboratory of Photochemical Conversion and Optoelectronic materials & CAS-HKU Joint laboratory on New materials Technical Institute of Physics and Chemistry Chinese Academy of Sciences

Photoactive complexes of nonprecious transition metals, mainly including those in the first-row and partially the second-row of the Periodic table of elements, have received increasing attention in view of their low cost and long-term sustainability. They are recognized as promising alternatives to noble transition metal complex congeners that have been extensively studied in optoelectronic devices, artificial photosynthesis, photocatalysis, biodiagnostics, and therapeutics, etc. This review is devoted to a comprehensive summary on the classical and recent advances on photoactive nonprecious transition metal complexes, including photoactive Zr, V, Cr, Mo, and W complexes, Mn complexes and hybrids, Fe, Co, Ni, and Cu complexes, and Zn and Cd complexes and hybrids. A particular focus is given on the molecular design, modulation of photophysical and photochemical properties, and applications of the representative and lately-developed nonprecious metal complexes. In addition, a perspective on the future development in this field is provided at the end of this review.

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SYNTHESIS AND CHARACTERIZATION OF POLY[(METHYLSILYLENE ETHYNYLENEPHENYLENEETHYNYLENE)-CO-(DIMETHYLSILYLENE ETHYNYLENEPHENYLENEETHYNYLENE)]S

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Chinese Journal of Polymer Science 2010年第2期28卷 199-207页

作者：黄发荣 key laboratory for Specially Functional polymeric materials and Related technology of the Ministry of Education East China University of Science and Technology

A series of poly[（methylsilylene ethynylenephenyleneethynylene）-co-（dimethylsilylene ethynylenephenyleneethynylene）]s were synthesized by the incorporation of various ratios of methylsilylene to dimethylsilylene units into the polymer chain backbone. The resultant copolymers were soluble in a variety of common organic solvents at room temperature. The copolymers were characterized by FT-IR, ^1H-NMR, GPC, rheological analysis, differential scanning calorimetry （DSC） and thermogravimetric analysis （TGA）. The results showed that the copolymers exhibited good processability and cured at low temperatures like 200℃. The curing reactions involved in hydrosilylation of Si-H and alkyne groups and the polymerization of alkynes. Td5 （5% weight loss） of the cured copolymers ranged from 629℃ to 686℃, and the decomposition residues of cured copolymers at 1000℃ ranged from 88.1% to 90.9% under nitrogen. Thermal stability of the copolymers increased with the introduction of methylsilylene traits into polymer chains. The cured copolymers were sintered at 1450℃, and the results of X-ray diffraction analysis showed that β-SIC was formed in the sintered products.

关键词： Silicon-containing arylacetylene resin Polymer with methylsilylene and dimethysilyene units mdiethynylbenzene Thermally stable polymer High performance resin.

Toughening of Poly(propylene carbonate) by Carbon Dioxide Copolymer Poly(urethane-amine) via Hydrogen Bonding Interaction

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Chinese Journal of Polymer Science 2015年第6期33卷 838-849页

作者：顾林 Qing-yun Wu 余海斌 key laboratory of Marine New materials and application technology Zhejiang Key Laboratory of Marine Materials and Protective TechnologiesNingbo Institute of Materials Technology and EngineeringChinese Academy of Sciences Department of Polymer Science and Engineering Faculty of Materials Science and Chemical EngineeringNingbo University

A carbon dioxide copolymer poly（urethane-amine）（PUA） was blended with poly（propylene carbonate）（PPC） in order to improve the toughness and flexibility of PPC without sacrificing other mechanical properties. Compared with pure PPC, the PPC/PUA blend with 5 wt% PUA loading showed a 400% increase in elongation at break, whilst the corresponding yielding strength remained as high as 33.5 MPa and Young＇s modulus showed slightly decrease. The intermolecular hydrogen bonding interaction in PPC/PUA blends was comfirmed by FTIR, 2D IR and XPS spectra analysis, and finely dispersed particulate structure of PUA in PPC was observed in the SEM images, which provided good evidence for the toughening mechanism of PPC.

关键词： Carbon dioxide copolymer Blend Toughening Poly(propylene carbonate) Poly(urethane-amine).

Helical supramolecular nanorods via sequential meticulous tailoring of noncovalent interaction and light irradiation

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Science China Chemistry 2022年第9期65卷 1749-1757页

作者： Zhenghui Liu Yuan Yao Xinfeng Tao Jie Wei Shaoliang Lin Shanghai key laboratory of Advanced polymeric materials Key Laboratory for Ultrafine Materials of Ministry of EducationSchool of Materials Science and EngineeringEast China University of Science and TechnologyShanghai 200237China

Polymers are widely recognized to entail random conformations in good solvent governed by the need for achieving the highest entropy to reach thermodynamic *** this context,it remains grand challenging to directly arrange them into ordered conformation as building blocks for further self-assembling into hierarchal ***,we report a simple yet viable strategy to progressively assemble rationally designed azobenzene-containing alternating copolymer(i.e.,poly(binaphthylspacer-azobenzene-alt-hexaethylene glycol),denoting P(BNPSAzo-alt-EG_(6))_(24))into helical supramolecular ***,P(BNPSAzo-alt-EG_(6))_(24) chains in good solvent are firstly self-assembled into helical single molecular micelles in good solvent via intramolecular π-π interaction between binaphthyl groups as well as between azobenzene ***,by simply introducing water into the solution that is allowed to dwell for a certain period of time,single molecular micelles are selfassembled into well-defined ***,these isotropic vesicles could be further transformed into anisotropic helical supramolecular nanorods with enhanced aggregate-induced emission(AIE)capability driven by repeated,light-triggered cistrans isomerization of azobenzene moieties with the retention of π-π interacted binaphthyl *** study highlights a facile route to yielding morphology-rich,functional assemblies from a single polymer via judiciously exploiting non-covalent interaction and light of different wavelength as highly effective trigger in a non-invasive manner for potential applications in controlled release and fluorescent labelling.

关键词： alternating polymer conformational organization assembly chirality transmission light response azobenzene

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An unconventional phase field modeling of domains formation and evolution in tetragonal ferroelectrics

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Science China(Technological Sciences) 2016年第7期59卷 1059-1064页

作者： ZHOU YouGang PENG JinLin PAN Kai LIU YunYa key laboratory of Low Dimensional materials and application technology of Ministry of Education and Key Laboratory of Materials Design and Preparation Technology of Hunan Province School of Materials Science and Engineering Xiangtan University

based on characteristic functions of variants, we developed an unconventional phase field modeling for investigating domains formation and evolution in tetragonal ferroelectrics. In order to develop this computational approach, we constructed the anisotropy energy of tetragonal variants, which is used instead of Landau-Devonshire potential in the conventional phase field method, resulting in that much fewer parameters are needed for simulations. This approach is advantageous in simulations of emerging ferroelectric materials. We employ it to study the formation and evolution of domains in tetragonal barium titanate single crystal, as well as the nonlinear behaviors under cyclical stress and electric field loading. A multi-rank laminated ferroelectric domain pattern, 90° domain switching accompanied by polarization rotation, and 180° domain switching accompanied by move of domain wall are predicted. It is found that the speed of 90° domain switching is slower than that of 180° domain switching, due to both polarization and transformation strain changed in 90° domain switching. It also suggests that large strain actuation can be generated in single crystal ferroelectrics via combined electromechanical loading inducing 90° domain switching. The good agreement between simulation results and experimental measurements is observed.

关键词： phase field simulation ferroelectric domains formation and evolution ferroelectric materials

Chemical Recycling of Poly(ethylene furanoate)into Value-added Poly(ethylene-co-isosorbide furanoate)

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Chinese Journal of Polymer Science 2023年第10期41卷 1533-1542页

作者： Jing Li Sheng Wang Huan-Jun Lu Ying-Jia Lan Xiao-Hong Li Ying-Feng Tu Jiangsu Engineering laboratory of Novel Functional polymeric materials State and Local Joint Engineering Laboratory for Novel Functional Polymeric MaterialsCollege of ChemistryChemical Engineering and Materials ScienceSoochow UniversitySuzhou215123China Jiangsu key laboratory for Micro and Nano Heat Fluid Flow technology and Energy application School of Physical Science and TechnologySuzhou University of Science and TechnologySuzhou215009China

We present here a novel strategy for the chemical recycling of bio-based poly(ethylene furanoate)s(PEF)to value-added high-performance bio-based poly(ethylene-co-isosorbide furanoate)(PEIF)copolyesters by the combination of cyclodepolymerization method with rapid cascade polycondensation-coupling ring-opening polymerization(PROP).The solution cyclodepolymerization of commercially available PEF affords cyclic oligo(ethylene 2,5-furandicarboxylate)s(COEFs),and the effects of reaction conditions on the yield of COEFs were *** copolyesters with different isosorbide(IS)contents were synthesized via the cascade PROP of COEFs with IS,which show significant enhanced glass transition *** melt spinning,PEIF fibers with different orientation factors were prepared,with excellent thermal stability and mechanical *** obtained PEIF fibers can lift a weight∼25000 times higher than its *** PEIF fibers are stable under ambient conditions but are biodegradable following the“surface erosion”*** sustainable value-added biodegradable PEIF fibers offer a solution to the environmentally friendly fibers.

关键词： bio-based Chemical recycling Fiber PROP Sustainable

Phase constitution and microstructure of Ce–Fe–B strip-casting alloy

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Chinese Physics B 2014年第10期23卷 508-512页

作者：严长江郭帅陈仁杰李东闫阿儒 key laboratory of Magnetic materials and Devices Ningbo Institute of Material Technology and EngineeringChinese Academy of Sciences zhejiang Province key laboratory of Magnetic materials and application technology Ningbo Institute of Material Technology and EngineeringChinese Academy of Sciences

The strip-casting technique plays an important role in fabricating high coercivity sintered magnet. In this paper, we investigate the phase constitution and the microstructure of rapidly solidified Ce-Fe-B alloy fabricated by strip-casting. We find that the Ce2FelgB phase coexists with Fe, Fe2B, and CeFe2 phases in the Ce-Fe-B strips. The eutectic stucture consisting of Fe and Fe2B is encased in Ce2Fe14B grains, which is blocked by the CeFe2 grains at triple junctions, indicating that the microstructure of Ce-Fe-B strip is characteristic of a peritectic solidification. Thermal analysis indicates that the large supercooling of Ce2Fe14B results in the residual Fe and Fe2B. The microstructural optimization in Ce-Fe-B strips without Fe and Fe2B could be achieved by a heat treatment of 1000 ℃.

关键词： magnetic material Ce-Fe-B microstructure rapid solidification

Enhanced energy storage behaviors in free-standing antiferroelectric Pb(Zr_(0.95)Ti_(0.05))O_3 thin membranes

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Chinese Physics B 2016年第8期25卷 388-392页

作者：左正笏詹清峰陈斌杨华礼刘宜伟刘鲁萍谢亚丽李润伟 key laboratory of Magnetic materials and Devices Ningbo Institute of Material Technology and EngineeringChinese Academy of Sciences zhejiang Province key laboratory of Magnetic materials and application technology Ningbo Institute of Material Technology and Engineering Chinese Academy of Sciences

Free-standing antiferroelectric Pb（Zr0.95Ti0.05O3（PZT（95/5）） thin film is fabricated on 200-nm-thick Pt foil by using pulsed laser deposition.X-ray diffraction patterns indicate that free-standing PZT（95/5） film possesses an α-axis preferred *** critical electric field for the 300-nm-thick free-standing PZT（95/5） film transiting from antiferroelectric to ferroelectric phases is increased to 770 kV/cm,but its saturation polarization remains almost unchanged as compared with that of the substrate-clamped PZT（95/5） *** energy storage density and energy efficiency of the substrate-clamped PZT（95/5） film are 6.49 J/cm^3 and 54.5%,*** contrast,after removing the substrate,the energy storage density and energy efficiency of the free-standing PZT（95/5） film are enhanced up to 17.45 J/cm^3 and 67.9%,respectively.

关键词： antiferroelectric films freestanding energy storage

Effects of Nd-Ga intergranular addition on microstructure and magnetic properties of heavy-rare-earth-free Nd-Fe-B sintered magnets

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Journal of Rare Earths 2022年第6期40卷 924-929,I0003页

作者： Jinhao Zhu Guangfei Ding Lei Jin Zhehuan Jin Bo Zheng Shuai Guo Renjie Chen Aru Yan CAS key laboratory of Magnetic materials and Devices and Zhejiang Province Key Laboratory of Magnetic Materials and Application TechnologyNingbo Institute of Materials Technology and EngineeringChinese Academy of SciencesNingbo 315201China University of Chinese Academy of Sciences Beijing 100049China

In this study,we propose an approach of grain boundary modification that can significantly increase the coercivity of the B-lean Nd-Fe-B sintered magnets by intergranular addition of *** coercivity is substantially enhanced from 1.51 to 2.04 T through optimizing the microstructure and adjusting the phase composition for the grain boundary phase in the annealed *** matrix grains are covered by a continuous thin grain boundary phase accompanying the formation of intermetallic Nd_(6)Fe_(13)Ga *** analysis of magnetic behaviors above Curie temperature confirms that the grain boundary phase of annealed Nd-Ga doped magnets appears to be non-ferromagnetic,facilitating the intergrain exchange *** observation in grain boundary area indicates that some surface of the matrix grain is dissolved in the formation process of the Nd_(6)Fe_(13)Ga *** gives rise to a decrease in the proportion of matrix grains and saturation magnetization of the *** detailed relationship between magnetic properties and microstructure is discussed based on these results.

关键词： Nd-Fe-B sintered Magnet Magnetic properties Grain boundary Microstructures Rare earths