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Chinese Journal of Polymer Science 2016年第12期34卷 1510-1522页

作者： You Lv hao Zhu Min-fang An hao-jun xu Li Zhang 王宗宝 Ningbo Key Laboratory of Specialty Polymers Faculty of Materials Science and Chemical EngineeringNingbo UniversityNingbo 315211China

The multiple endothermic peaks of poly（3-hydroxybutyrate-co-3-hydroxyvalerate）（P（HB-co-HV）） in differential scanning calorimetry （DSC） results, as one representative phenomenon of polymer with unique cocrystallization behavior, were generally considered as the results of melting/recrystallization. In this study, wide angle X-ray diffraction （WAXD） and small angle X-ray scattering （SAXS） experiments were conducted to analyze the phenomena of multiple endothermic peaks in DSC results. The results of these analyses indicated that the multiple endotherms were mainly caused by different lamellae structures. For P（HB-co-HV） with lower HV content, it was comprised of two structures of HV total exclusion and HV partial inclusion in the crystal lamellae. For P（HB-co-HV） with higher HV content, it was also comprised of two structures of HV total inclusion and HV partial inclusion in the crystal lamellae. However, only structure with HV partial inclusion in the crystal lamellae remained existing after first melting peak for all samples.

关键词： P(HB-co-HV) Isodimorphism Multiple endotherms Uniform lamellae Sandwich lamellae.

Structure and Properties of Gel-spun Ultra-high Molecular Weight Polyethylene Fibers with High Gel Solution Concentration

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Chinese Journal of Polymer Science 2017年第4期35卷 524-533页

作者： Min-fang An You Lv hao-jun xu Qun-Gu 王宗宝 Ningbo Key Laboratory of Specialty Polymers Faculty of Materials Science and Chemical Engineering Ningbo University Ningbo 315211 China College of Material Engineering Ningbo University of Technology Ningbo 315211 China

The gel-spun ultra-high molecular weight polyethylene （UHMWPE） fibers were prepared at the industrial production line with different gel solution concentrations of 15 wt%, 18 wt% and 24 wt%. The difference in ultimate structure and mechanical properties of UHMWPE fibers for different gel solution concentrations were analyzed by tensile testing, differential scanning calorimetry （DSC）, wide angle X-ray diffraction （WAXD） and small angle X-ray scattering （SAXS）. With the increase of gel solution concentration, the ultimate mechanical properties of UHMWPE fibers were decreased and the crystallization and orientation of UHMWPE fibers became inferior. Besides, both the average shish length （（Lshsh）） and shish misorientation （B0） of UHMWPE fibers were decreased with the increase of gel solution concentration. In addition, the appropriate increase of spinning temperature led to the further optimization of the ultimate structure and mechanical properties of UHMWPE fibers.

关键词： UHMWPE fibers Gel solution concentration Orientation Crystallization Shish structure

Characterization of Structural Knot Distributions in UHMWPE Fibers

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Chinese Journal of Polymer Science 2016年第5期34卷 606-615页

作者： hao-jun xu Min-fang An You Lv 王宗宝 Qun Gu Ningbo Key Laboratory of Specialty Polymers Faculty of Materials Sctence and Chemical Engineering Ningbo University Ningbo 315211 China College of Material Engineering Ningbo University of Technology Ningbo 315211 China

Microbeam wide-angle X-ray diffraction（WAXD） experiments were carried out at different structural knot positions of SIOC and M4 fibers of ultra-high molecular weight polyethylene（UHMWPE）. The optical microscope images revealed that SIOC fiber had bamboo-like structural knots, and M4 fiber had chaotic distribution of structural knots. WAXD patterns showed the monoclinic unit cell in the whole M4 fiber, but different lamellar orientations in the bamboo joint of SIOC fiber. In addition, small-angle X-ray scattering（SAXS） patterns confirmed that the SIOC fiber contained uniform distribution of shish structures, and differential scanning calorimetry（DSC） measurements showed that its less branched and short chains benefited the orthorhombic-hexagonal phase transformation.

关键词： UHMWPE shish hexagonal calorimetry SAXS lamellar bamboo crystalline chains WAXD

The Influence of Chitin Nanocrystals on Structural Evolution of Ultra-high Molecular Weight Polyethylene/Chitin Nanocrystal Fibers in Hot-drawing Process

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Chinese Journal of Polymer Science 2016年第11期34卷 1373-1385页

作者： Min-fang An hao-jun xu You Lv Li Zhang Qun Gu Feng Tian 王宗宝 Ningbo Key Laboratory of Specialty Polymers Faculty of Materials Science and Chemical Engineering Ningbo University Ningbo 315211 China College of Material Engineering Ningbo University of Technology Ningbo 3151006 China Shanghai Institute of Applied Physics Chinese Academy of Sciences Shanghai 201204 China

Ultra-high molecular weight polyethylene（UHMWPE）/chitin nanocrystal（CNC） fibers were prepared. Compared with the pure UHMWPE fibers, the ultimate tensile strength and Young＇s modulus of UHMWPE/CNC fibers are improved by 15.7% and 49.6%, respectively, with the addition of chitin nanocrystals（CNCs） of 1 wt%. The melting temperature（Tm） of UHMWPE/CNC fibers was higher than that of pure UHMWPE fibers. Pure UHMWPE fibers and UHMWPE/CNC fibers were characterized with respect to crystallinity, orientation and kebab structure by wide-angle X-ray diffraction（WAXD）, small-angle X-ray scattering（SAXS） and scanning electron microscopy（SEM）. It is found that the CNCs act as the shish structure in UHMWPE/CNC fibers and the kebab crystals are grown around the CNCs. There was almost no difference between pure UHMWPE fibers and UHMWPE/CNC fibers in orientation. But the degree of crystallinity of various stages of UHMWPE/CNC fibers was respectively higher than the corresponding stage of pure UHMWPE fibers. Moreover, the addition of 1 wt% CNCs improved the thickness of kebab crystals and accelerated the transformation of kebab to shish.

关键词： UHMWPE shish crystallinity modulus SAXS WAXD drawing melting chitin ultimate

Heat distribution model under hydrogen-rich low-carbon conditions in blast furnace

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Journal of Iron and Steel Research International 2024年第3期31卷 584-594页

作者： Gang Wang jun xu Kun He Zhong-ping Zou hao Bai School of Metallurgy and Ecological Engineering University of Science and Technology BeijingBeijing 100083China CISDI Low-Carbon Blast Furnace Research Office MCC Low-Carbon Technology Research InstituteChongqing 401122China

Low carbon development of blast furnaces is one of the key technological directions in the current development of *** to the differences in the physical and chemical properties of hydrogen and carbon,hydrogen-rich media entering a blast furnace will change the heat distribution,thus affecting the stability of ***,a heat distribution model was proposed to study the temperature distribution in a blast furnace,simultaneously considering gas-solid heat exchange,slag and iron melting,and chemical *** model was used to analyze the temperature distribution of a 2300 m^(3) blast furnace and was verified via comparison with actual production ***,the effects of the injection rate of hydrogen-rich media,H2 concentration,and oxygen enrichment rate of the blast on the temperature distribution were *** indicated that the increase in the injection rate of the hydrogen-rich media decreased the amount of direct reduction and led to an increase in the furnace ***,an increase in the oxygen enrichment rate led to a decrease in the furnace temperature,but could reduce the solid fuel ratio,while the change in H2 concentration had less effect on the temperature *** combination of hydrogen-rich media injection and the increase in the oxygen enrichment rate would help to adjust the temperature distribution to the same level as the conventional blast furnace conditions.

关键词： Heat distribution Blast furnace Low-carbon condition Hydrogen enrichment Calculation model

αDecay in extreme laser fields within a deformed Gamow-like model

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Nuclear Science and Techniques 2024年第2期35卷 131-144页

作者： Qiong Xiao jun-hao Cheng Yang-Yang xu You-Tian Zou jun-Gang Deng Tong-Pu Yu Department of Physics National University of Defense TechnologyChangsha 410073China College of Science China Three Gorges UniversityYichang 443002China

In this study, the effect of extreme laser fields on the α decay process of ground-state even–even nuclei was *** the deformed Gamow-like model, we found that state-of-the-art lasers can cause a slight change in the α decay penetration probability of most nuclei. In addition, we studied the correlation between the rate of change of the α decay penetration probability and angle between the directions of the laser electric field and α particle emission for different nuclei. Based on this correlation, the average effect of extreme laser fields on the half-life of many nuclei with arbitrary α particle emission angles was calculated. The calculations show that the laser suppression and promotion effects on the α decay penetration probability of the nuclei population with completely random α particle-emission directions are not completely *** remainder led to a change in the average penetration probability of the nuclei. Furthermore, the possibility of achieving a higher average rate of change by altering the spatial shape of the laser is explored. We conclude that circularly polarized lasers may be helpful in future experiments to achieve a more significant average rate of change of the α decay half-life of the nuclei population.

关键词： αDecay Deformed Gamow-like model Half-lives Extreme laser field Penetration probability

Span-based joint entity and relation extraction augmented with sequence tagging mechanism

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Science China(Information Sciences) 2024年第5期67卷 84-98页

作者： Bin JI Shasha LI hao xu Jie YU jun MA Huijun LIU Jing YANG College of Computer National University of Defense Technology

Span-based joint extraction simultaneously conducts named entity recognition(NER) and relation extraction(RE) in a text span form. However, since previous span-based models rely on span-level classifications, they cannot benefit from token-level label information, which has been proven advantageous for the task. In this paper, we propose a sequence tagging augmented span-based network(STSN), a spanbased joint model that can make use of token-level label information. In STSN, we construct a core neural architecture by deep stacking multiple attention layers, each of which consists of three basic attention *** the one hand, the core architecture enables our model to learn token-level label information via the sequence tagging mechanism and then uses the information in the span-based joint extraction; on the other hand, it establishes a bi-directional information interaction between NER and RE. Experimental results on three benchmark datasets show that STSN consistently outperforms the strongest baselines in terms of F1,creating new state-of-the-art results.

关键词： joint extraction named entity recognition relation extraction span sequence tagging mechanism

Simulation of the Ecosystem Productivity Responses to Aerosol Diffuse Radiation Fertilization Effects over the Pan-Arctic during 2001–19

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Advances in Atmospheric Sciences 2024年第1期41卷 84-96页

作者： Zhiding ZHANG xu YUE hao ZHOU jun ZHU Yadong LEI Chenguang TIAN Jiangsu Key Laboratory of Atmospheric Environment Monitoring and Pollution Control Collaborative Innovation Center of Atmospheric Environment and Equipment TechnologySchool of Environmental Science and EngineeringNanjing University of Information Science&Technology(NUIST)Nanjing 210044China Climate Change Research Center Institute of Atmospheric Physics(IAP)Chinese Academy of Sciences(CAS)Beijing 100029China University of Chinese Academy of Sciences Beijing 100049China State Key Laboratory of Severe Weather&Key Laboratory of Atmospheric Chemistry of CMA Chinese Academy of Meteorological SciencesBeijing 100081China

The pan-Arctic is confronted with air pollution transported from lower *** have shown that aerosols help increase plant photosynthesis through the diffuse radiation fertilization effects(DRFEs).While such DRFEs have been explored at low to middle latitudes,the aerosol impacts on pan-Arctic ecosystems and the contributions by anthropogenic and natural emission sources remain less ***,we perform regional simulations at 0.2o×0.2ousing a well-validated vegetation model(Yale Interactive terrestrial Biosphere,YIBs)in combination with multi-source of observations to quantify the impacts of aerosol DRFEs on the net primary productivity(NPP)in the pan-Arctic during *** show that aerosol DRFEs increase pan-Arctic NPP by 2.19 Pg C(12.8%)yr^(-1)under clear-sky conditions,in which natural and anthropogenic sources contribute to 8.9% and 3.9%,*** all-sky conditions,such DRFEs are largely dampened by cloud to only 0.26 Pg C(1.24%)yr^(-1),with contributions of 0.65% by natural and 0.59% by anthropogenic *** aerosols cause a positive NPP trend of 0.022% yr^(-1)following the increased fire activities in the *** contrast,anthropogenic aerosols induce a negative trend of-0.01% yr^(-1)due to reduced emissions from the middle *** trends in aerosol DRFEs show a turning point in the year of 2007 with more positive NPP trends by natural aerosols but negative NPP trends by anthropogenic aerosols *** affected by modeling uncertainties,this study suggests a likely increasing impact of aerosols on terrestrial ecosystems in the pan-Arctic under global warming.

关键词： diffuse radiation fertilization effects anthropogenic aerosols natural aerosols pan-Arctic net primary productivity

TRIM21-dependent ultrasmall chiral gold nanoparticles for preventing microglia senescence against Alzheimer's disease

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Science China Chemistry 2024年第4期67卷 1360-1372页

作者： Meiru Lu Changlong hao Liguang xu Feng Yu Jiwei Jiang Yanli Wang jun xu Hua Kuang Chuanlai xu Maozhong Sun International Joint Research Laboratory for Biointerface and Biodetection State Key Laboratory of Food Science and ResourcesSchool of Food Science and TechnologyJiangnan UniversityWuxi 214122China Institute of Life Sciences Jiangsu UniversityZhenjiang 212013China Department of Neurology Beijing Tiantan HospitalCapital Medical UniversityBeijing 100050China National Clinical Research Center for Neurological Diseases Beijing 100070China

Tripartite motif 21(TRIM21)is an E3 ubiquitin ligase that shows great promise for protein degradation through ***,ultrasmall chiral gold nanoparticles(D-or L-NPs)modified by D-or L-glutathione ligands were *** conjugated with an NLR family pyrin domain-containing protein 3(NLRP3)antibody(D-NP-a NLRP3 or L-NP-a NLRP3),DNP-a NLRP3 showed effective delivery efficiency of the antibody into microglia and prevented Aβ-mediated microglia senescence,and p16^(ink4a),a marker of senescence,in the microglia was reduced by 90.3%±7.8% while L-NP-a NLRP3 decreased by 48.01%±3.1%.Mechanistic investigations revealed that the D-NP-a NLRP3((1.5±0.3)×10^(7)M^(-1))exhibited sixteen-fold larger binding affinity to transmembrane glycoprotein SLC3A2 than L-type((9.5±2.7)×10^(5)M^(-1)),which led to a high efficiency of antibody delivery and TRIM21-dependent NLRP3 ***,the blood-brain barrier(BBB)-crossing ability of chiral NP-a NLRP3 as well as NLRP3 degradation was demonstrated in *** APP/PS1 Alzheimer's disease(AD)model mice experiments exhibited a reduction of 89.7%±6.8% for the NLRP3 protein and 84.2±7.5% for p16^(ink4a)following the intravenous administration of D-NP-a NLRP3 once a week for 60 ***,the levels of the AD markers Aβ and phosphorylatedTau in the brains were reduced by 86.2%±8.2% and 81.6%±9.1%;these were 2.1-fold and 1.9-fold higher than those treated with L-NP-a NLRP3,*** studies provide a method to rescue AD-like pathologies and prevent senescence.

关键词： chiral gold nanoparticles amyloid-β NLRP3 TRIM21 senescence Alzheimer's disease

Rational design of metal selenides nanomaterials for alkali metal ion(Li^(+)/Na^(+)/K^(+))batteries:current status and perspectives

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Rare Metals 2024年第5期43卷 1906-1931页

作者： Rui Sun Feng xu Cai-Hong Wang Sheng-jun Lu Yu-Fei Zhang hao-Sen Fan College of Materials Science and Metallurgy Engineering Guizhou UniversityGuiyang550025China School of Chemistry and Chemical Engineering Guangzhou UniversityGuangzhou510006China

Recently,metal selenides have obtained widespread attention as electrode materials for alkali(Li^(+)/Na^(+)/K^(+))batteries due to their promising theoretical capacity and ***,metal selenides,similar to metal oxides and sulfides,also suffer from severe volume explosion during repeated charge/discharge processes,which results in the structure collapse and the following pulverization of electrode ***,it leads to poor cycle stability and influencing their further *** order to solve these issues,some special strategies,including elemental doping,coupling with carbon materials,synthesis of the bimetal selenides with heterostructure,etc.,have been gradually applied to design novel electrode materials with outstanding electrochemical ***,the recent research progress on metal selenides as anodes for alkali ion batteries is summarized,including the regulation of crystal structure,synthesis strategies,modification methods,and electrochemical mechanisms and ***,the challenges of metal selenides and the perspective for future electrode material design are *** is hoped to pave a way for the development of metal selenide electrode materials for the potential applications for alkali metal ion(Li^(+)/Na^(+)/K^(+))batteries.

关键词： Rational design Metal selenides Nanostructure Li^(+) batteries Na^(+) batteries K^(+) batteries