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Reprocessible Epoxy Networks with Tunable Physical Properties:Synthesis,Stress Relaxation and Recyclability

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Chinese Journal of Polymer Science 2018年第5期36卷 641-648页

作者： Jia-Hui Chen Xu-Pei An Yi-Dong Li Ming Wang jian-bing zeng School of Chemistry and Chemical Engineering Southwest University

In order to extend the application of epoxy vitrimer, 1,4-cyclohexanedicarboxylic acid（CHDA） was used as a co-curing agent and structure modifier for sebacic acid（SA） cured diglycidyl ether of bisphenol A（DGEBA） epoxy vitrimer to tailor the mechanical properties of epoxy vitrimers with 1,5,7-triazabicylo[4.4.0]dec-5-ene（TBD） as a transesterification catalyst. The glass transition temperature（Tg） of vitrimer increased gradually with the increase in CHDA content. Vitrimers behaved from elastomer to tough and hard plastics were successfully achieved by varying the feed ratio of CHDA to SA. Both the Young＇s modulus and storage modulus increased apparently with the increase in CHDA content. Stress relaxation measurement indicated that more prominent stress relaxation occurred at elevated temperatures and the stress relaxation decreased with the increase of CHDA content due to the reduced mobility of the vitrimer backbone. The vitrimers showed excellent recyclability as evidenced by the unchanged gel fraction and mechanical properties after compression molded for several times. With tunable mechanical properties, the epoxy vitrimers may find extensive potential applications.

关键词： Epoxy vitrimer Mechanical properties Stress-relaxation Recyclability

Unlocking the Potential of Poly(butylene succinate)through Incorporation of Vitrimeric Network Based on Dynamic Imine Bonds

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Chinese Journal of Polymer Science 2024年第10期42卷 1414-1424,I0006页

作者： Shan-Song Wu Hui-Juan Lu Yi-Dong Li Shui-Dong Zhang jian-bing zeng Chongqing Key Laboratory of Soft-Matter Material Manufacturing School of Chemistry and Chemical EngineeringSouthwest UniversityChongqing400715China School of Mechanical and Automotive Engineering South China University of TechnologyGuangzhou510640China

Poly(butylene succinate)(PBS)exhibits many advantages,such as renewability,biodegradability,and impressive thermal and mechanical properties,but is limited by the low melt viscosity and strength resulted from the linear *** address this,vitrimeric network was introduced to synthesize PBS vitrimers(PBSVs)based on dynamic imine bonds through melt polymerization of hydroxyl-terminated PBS with vanillin derived imine containing compound and hexamethylene diisocyanate using trimethylolpropane as a crosslinking *** with different crosslinking degrees were synthesized through changing the content of the crosslinking *** effect of crosslinking degree on the thermal,theological,mechanical properties,and stress relaxation behavior of the PBSVs was studied in *** results demonstrated that the melt viscosity,melt strength,and heat resistance were enhanced substantially without obvious depression in crystallizability,thermal stability,and mechanical properties through increasing crosslinking *** addition,the PBSVs exhibit thermal reprocessability with mechanical properties recovered by more than 90%even after processing for three ***,PBSV with improved melt properties shows significantly improved foamability compared to commercial *** research contributes to the advancement of polymer technology by successfully developing PBS vitrimers with improved properties,showcasing their potential applications in sustainable and biodegradable materials.

关键词： Poly(butylene succinate) Vitrimer Imine bonds Foamability

Selective fusion in adolescent idiopathic scoliosis

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Chinese Medical Journal 2008年第15期121卷 1456-1461页

作者： WANG Ting XU jian-guang zeng bing-fang Department of Orthopedics Sixth People's Hospital Affiliated to Shanghai Jiao Tong University Shanghai 200233 China

Despite the continual evolution in the surgical treatment of adolescent idiopathic scoliosis （AIS）,the goals of surgery remain to correct and stabilize the deformity in three dimensions, to maintain equilibrium of the shoulders and trunk, and to leave as many mobile spinal segments as possible. The essence is to fuse the smallest possible number of vertebrae to maintain maximum residual mobility, but end with corrected and well-balanced spine. Selective fusion is termed when both the main thoracic and thoracolumbar/lumbar （TL/L） curves deviate completely from the midline （Figure 1）, but only the major curve （the largest Cobb measurement） is fused, leaving the minor curve unfused and mobile. For the single curve, such as thoracic, thoracolumbar, or lumbar curve, there are fewer differences of opinion amongst spinal surgeons regarding the selection of the fusion level than the surgical approach. However, the choice of fusion levels in some types of curves, such as double curves and triple controversy issue. If the fusion is incorrect, it curvature deterioration, curves remains a difficult and decision to perform selective may result in postoperative shoulder imbalance, trunk decompensation, or even produce new deformity, an early revision by extending the fusion or reducing the correction may need. The non-selective approach rarely leads to early troubles that require a second procedure and is often perceived as being safer in the short-term. But it may be more difficult in the long-term as distal degeneration is more likely. This raises the question：＂Is it better to be safe in the short-term or take a chance avoiding later degenerative problems with a shorter motion-sparing fusion？＂ Thus, the aim of selective fusion is to identify the compensatory curves （minor curve） that will straighten spontaneously after correcting and fusing the major curve, thereby avoid the fusion of these flexible compensatory curves.

关键词： adolescent idiopathic scoliosis selective fusion surgery

A nuclide identification method ofγspectrum and model building based on the transformer

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Nuclear Science and Techniques 2025年第1期36卷 80-93页

作者： Fei Li Chu-Yang Luo Ying-Zi Wen Sheng Lv Feng Cheng Guo-Qiang zeng jian-Feng jiang bing-Hai Li College of Nuclear Technology and Automation Engineering Chengdu University of TechnologyChengdu 610000China Applied Nuclear Technology in Geosciences Key Laboratory of Sichuan Province Chengdu 610000China Department of Physics Universitat Politècnica de CatalunyaBarcelona 08028Spain Airborne Survey and Remote Sensing Center of Nuclear Industry Shijiazhuang 050000China Hebei Key Laboratory of Airborne Detection and Remote Sensing Technology Shijiazhuang 050000China

In current neural network algorithms for nuclide identification in high-background,poor-resolution detectors,traditional network paradigms including back-propagation networks,convolutional neural networks,recurrent neural networks,etc.,have been limited in research on γ spectrum analysis because of their inherent mathematical *** is difficult to make progress in terms of training data requirements and prediction *** contrast to traditional network paradigms,network models based on the transformer structure have the characteristics of parallel computing,position encoding,and deep stacking,which have enabled good performance in natural language processing tasks in recent ***,in this paper,a transformer-based neural network (TBNN) model is proposed to achieve nuclide identification for the first ***,the Geant4 program was used to generate the basic single-nuclide energy spectrum through Monte Carlo simulations.A multi-nuclide energy spectrum database was established for neural network training using random matrices of γ-ray energy,activity,and *** on the encoder–decoder structure,a network topology based on the transformer was built,transforming the 1024-channel energy spectrum data into a 32×32 energy spectrum sequence as the model *** experiments and adjustments of model parameters,including the learning rate of the TBNN model,number of attention heads,and number of network stacking layers,the overall recognition rate reached 98.7%.Additionally,this database was used for training AI models such as back-propagation networks,convolutional neural networks,residual networks,and long shortterm memory neural networks,with overall recognition rates of 92.8%,95.3%,96.3%,and 96.6%,*** indicates that the TBNN model exhibited better nuclide identification among these AI models,providing an important reference and theoretical basis for the practical application of transformers in the qualitative and quantitativ

关键词： Nuclide identification Neural network Transformer

Rational design of sustainable polyurethanes from castor oil: towards simultaneous reinforcement and toughening

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Science China Materials 2018年第7期61卷 993-1000页

作者： Xu-Pei An Jia-Hui Chen Yi-Dong Li jiang Zhu jian-bing zeng School of Chemistry and Chemical Engineering Southwest University Chongqing 400715 China College of Materials and Chemical Engineering Chongqing University of Arts and Sciences Chongqing 402160 China

Sustainable polyurethanes prepared from castor oil and diisocyanates show very low strength and toughness, due to the highly cross-linked and flexible structure. Herein, we report a new strategy to simultaneously reinforce and toughen castor oil-based polyurethane via incorporating a stiff component （isosorbide, IS） to enhance network stiffness and reduce crosslink density. The crosslinking degree de- creases while the strength, moduli, ductility and heat re- sistance significantly increase accordingly with increasing IS content. The tensile behaviors are tunable over a broad range （either as elastomers or as plastics） depending on the com- positions. The polyurethanes show excellent thermal stability with onset decomposition temperature higher than 280℃. The investigation provides a new hint for future design and fab- rication of high performance sustainable polymers from other vegetable oils.

关键词： sustainable polyurethane castor oil isosorbide crosslink density mechanical property

Flexible and wake-up free Hf_(0.5)Zr_(0.5)O_(2) ferroelectric thin films with ultra-low operation voltage and high polarization

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Journal of Advanced Ceramics 2024年第11期13卷 1844-1851页

作者： Jun-Hui Wang Tian-Peng Duan Jia-Jia Liao Zhi-Peng Wang Xin-Ran Huang Shi-Jie Jia Ke-Yu Bao Yu-Xin Fan bing-jian zeng Li-Mei jiang Min Liao Yi-Chun Zhou Qiong Yang Jie jiang School of Advanced Materials and Nanotechnology Xidian UniversityXi’an 710126China School of Materials Science and Engineering Xiangtan UniversityXiangtan 411105China Guangzhou Institute of Technology Xidian UniversityGuangzhou 510555China

Flexible and transparent hafnium oxide-based ferroelectric films are attracting widespread attention because of the increasing demand for wearable electronic ***,the ultra-low voltage operation with robust and stable ferroelectricity,which is a prerequisite for portable device applications,has not been realized ***,we report flexible Hf_(0.5)Zr_(0.5)O_(2) ferroelectric films with a saturation voltage of only 1.3/3 V and remanent polarization(2Pr)of 38/60µC·cm^(2).Negligible wake-up effect and superior stability resistance to compressive/tensile stress and high temperature up to 150°C are also *** polarization switching dynamics under bending are investigated based on the switching current measurement,suggesting that the intrinsic switching speeds keep almost constant at different bending *** addition,there is a negative correlation between the activation field and the compressive or tensile stress,which is due to the lowered energy barrier induced by the in-plane strain applied to the[111]-oriented hexagonal *** work sheds light on the application of flexible,stable,and HfO2-based ferroelectric thin films with ultra-low consumption.

关键词： flexible ferroelectrics Hf_(0.5)Zr_(0.5)O_(2) ultra-low voltage operation reliability

Irreversible electroporation combined with anti-programmed cell death protein 1 therapy promotes tumor antigen-specific CD8+T cell response

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World Journal of Gastrointestinal Oncology 2025年第3期17卷 237-245页

作者： Yang-Yang Ma Xiao-Hua Wang jian-Ying zeng Ji-bing Chen Li-Zhi Niu Guangzhou Fuda Cancer Hospital Guangzhou 510665Guangdong ProvinceChina Department of Oncology Guangzhou Fuda Cancer HospitalGuangzhou 510665Guangdong ProvinceChina

BACKGROUND Irreversible electroporation(IRE)is a novel local tumor ablation approach with the potential to activate the host’s immune ***,this approach is insufficient to prevent cancer progression,and complementary approaches are required for effective *** To assess the immunomodulatory effects and mechanism of IRE combined antiprogrammed cell death protein 1(PD-1)treatment in subcutaneous pancreatic cancer *** C57BL-6 tumor-bearing mice were randomly divided into four groups:Control group;IRE group;anti-PD-1 group;and IRE+anti-PD-1 ***-infiltrating T,B,and natural killer cell levels and plasma concentrations of T helper type 1 cytokines(interleukin-2,interferon-γ,and tumor necrosis factor-α)were ***-time PCR was used to determine the expression of CD8(marker of CD8+T cells)in tumor tissues of the mice of all groups at different points of *** growth curves of tumors were *** The results demonstrated that the IRE+anti-PD-1 group exhibited significantly higher percentages of T lymphocyte infiltration,including CD4+and CD8+T cells compared with the control ***,the IRE+anti-PD-1 group showed increased infiltration of natural killer and B cells,elevated cytokine levels,and higher CD8 mRNA *** volume was significantly reduced in the IRE+anti-PD-1 group,indicating a more pronounced therapeutic *** The combination of IRE and anti-PD-1 therapy promotes CD8+T cell immunity responses,leading to a more effective reduction in tumor volume and improved therapeutic outcomes,which provides a new direction for ablation and immunotherapy of pancreatic cancer.

关键词： Irreversible electroporation Pancreatic cancer Programmed cell death protein 1 blockade CD8+T cell Anticancer immunity

Fully bio-based,highly toughened and heat-resistant poly(L-lactide) ternary blends via dynamic vulcanization with poly(D-lactide) and unsaturated bioelastomer

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Science China Materials 2017年第10期60卷 1008-1022页

作者： Wan-Jie Si Xu-Pei An jian-bing zeng Yu-Kun Chen Yu-Zhong Wang School of Chemistry and Chemical Engineering Southwest University Chongqing 400715 China Key Laboratory of Polymer Processing Engineering Ministry of Education South China University of Technology Guangzhou 510641 China Center for Degradable and Flame-Retardant Polymeric Materials College of Chemistry State Key Laboratory of Polymer Materials Engineering National Engineering Laboratory of Eco-Friendly Polymeric Materials （Sichuan） Sichuan University Chengdu 610064 China

Inherent brittleness and low heat resistance are the two major obstacles that hinder the wide applications of poly（L-lactide）（PLLA）. In this study,we report a fully biobased,highly toughened and heat-resistant PLLA ternary blend,which was prepared by dynamic vulcanization of PLLA with poly（D-lactide）（PDLA） and an unsaturated bioelastomer（UBE）. The results indicated that during dynamic vulcanization PDLA cocrystallized with PLLA to form stereocomplex（SC） crystallites,which not only enhanced the molecular entanglement but also accelerated the crystallization rate of PLLA matrix. With increase in the content of PDLA,the matrix molecular entanglement increased while phase-separation was enhanced,which enabled the impact strength to increase first and then decrease. The ternary blends containing 10 wt.% PDLA showed the highest impact strength. The presence of SC crystallites makes it possible to achieve a fully sustainable PLLA/VUB/PDLA ternary blend with highly crystalline matrix under conventional injection molding,due to the high nucleation efficiency of SC towards crystallization of PLLA. The highly crystalline ternary blend showed excellent heat resistance and better impact toughness than high impact polystyrene.

关键词： poly(L-lactide) poly(D-lactide) dynamic vulcanization toughness heat resistance

Influence of heat treatment on microstructure of a newβ-solidifyingγ-TiAl alloy

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Journal of Iron and Steel Research International 2025年第1期32卷 239-248页

作者： Li Quan Xiao-bing Li Peng Xue Jun-jie Hao Kun Qian Bo Chen jian-zhong Li Kui Liu School of Metallurgy Northeastern UniversityShenyang110819LiaoningChina Department of Materials Science and Technology Ji Hua LaboratoryFoshan528200GuangdongChina

The high strength and stability of the full-lamellar structure guarantee the industrial application of theβ-solidifyingγ-TiAl ***,it is a huge challenge to design an alloy with good hot-deformability as well as the full-lamellar *** low-cost Ti-42.5Al-2Mn-0.4Mo-0.1B-0.1C(at.%)alloy was designed,which undergoes bothβandαsingle-phase region during the *** is found that the full-lamellar structure can be obtained by the solution heat treatment at 1230℃ for 20 min and then aging treatment at 800℃ for 3 ***,a new microstructure,namely,the pearlitic-like microstructure(PM)induced by theα_(2)/γ→βo+γcellular reaction was observed when the aging temperature is increased to above 800℃.The volume fraction of the PM is gradually increased from 0%to 25.5%,65%,and 94%according to elevated aging temperature from 800 to 900,1000,and 1050℃,*** mechanism of the reducedα_(2)/γlamellae and PM formation was discussed regarding the heterogeneous distribution ofβstabilizing elements and the interface energy stored inα_(2)/γlamellae.

关键词： β-γ-TiAl Alloy design Two-step heat treatment Full-lamellar structure Cellular reaction