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Hyper-crosslinked Conjugated Microporous Polymers with Increased Micropores Promotes Confining Polymerization for Electromagnetic Absorption Application

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Chinese Journal of Polymer Science 2023年第8期41卷 1305-1316,I0011页

作者： Hao Chen Fang-Yuan Chu Hai-Yan Zhuang Lu Wang zhi-Min Ye Wei Dong zhi-peng xie A-Ming xie School of Mechanical Engineering Nanjing University of Science&TechnologyNanjing 210094China State Key Laboratory for Marine Corrosion and Protection Luoyang Ship Material Research Institute(LSMRI)Xiamen 361100China School of Chemistry and Chemical Engineering Nanjing University of Science&TechnologyNanjing 210094China

Conjugated microporous polymers have excellent skeleton structures but poor electrical conductivity limits their applications in microwave *** solve this problem,a strategy of molecular expansion and confining polymerization is proposed in this work to synthesize conductive hyper-crosslinked conjugated microporous *** topology of the conjugated microporous polymer is changed into a three-dimensional skeleton structure with high specific surface area by using molecular expansion technique,and the controlled growth of polypyrrole in the channel constructs a unique network *** balance of excellent composite backbone structure,proper conductivity,attenuation capability and impedance matching enable the material to exhibit electromagnetic wave absorption *** a result,with low filler loading of 10 wt%,a strongest reflection loss of-52.68 d B and a maximum effective bandwidth of 5.76 ***,CST simulations of the radar scattering cross section have been carried out to verify the excellent material *** study provides new concepts for new conductive polymers and broadens the application of hyper-crosslinked conjugated microporous polymer in the field of electromagnetic wave absorption.

关键词： Hyper-crosslinked conjugated microporous polymer Electromagnetic wave absorbing Molecular expansion Polypyrrole

Injection molding of ultra-fine Si_3N_4 powder for gas-pressure sintering

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International Journal of Minerals,Metallurgy and Materials 2015年第6期22卷 654-659页

作者： Xian-feng Yang Jiang-hong Yang xie-wen Xu Qi-cheng Liu zhi-peng xie Wei Liu College of Physics and Electronics Science Changsha University of Science and Technology School of Materials Science and Engineering Tsinghua University

The ceramic injection molding technique was used in the gas-pressure sintering of ultra-fine Si3N4 powder. The feedstock＇s flowability, debinding rate, defect evolution, and microstructural evolution during production were explored. The results show that the solid volume loading of less than 50vol% and the surfactant mass fraction of 6wt% result in a perfect flowability of feedstock; this feedstock is suitable for injection molding. When the debinding time is 8 h at 40°C, approximately 50% of the wax can be solvent debinded. Defects detected during the preparation are traced to improper injection parameters, mold design, debinding parameters, residual stress, or inhomogeneous composition distribution in the green body. The bulk density, Vickers hardness, and fracture toughness of the gas-pressure-sintered Si3N4 ceramic reach 3.2 g/cm^3, 16.5 GPa, and 7.2 MPa·m^1/2, respectively.

关键词： ceramic materials silicon nitride injection molding sintering near net shaping

A strategy to obtain a high-density and high-strength zirconia ceramic via ceramic injection molding by the modification of oleic acid

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International Journal of Minerals,Metallurgy and Materials 2017年第6期24卷 718-725页

作者： Jia-xin Wen Tian-bin Zhu zhi-peng xie Wen-bin Cao Wei Liu School of Materials Science and Engineering University of Science and Technology Beijing Sate Key Laboratory of New Ceramics and Fine Processing Department of Materials Science and Engineering Tsinghua University School of Electromechanical Engineering Guangdong University of Technology

Despite its unique high efficiency and good environmental compatibility, the water-soluble binder system still encounters problems achieving a desired sintered part via ceramic injection molding because of the poor compatibility and the powder-binder segregation between ceramic powders and binders. The objective of this study was to obtain a sintered part with excellent properties by introducing a small quantity of oleic acid to the surface of zirconia powders before the mixing process. As opposed to many previous investigations that focused only on the rheological behavior and modification mechanism, the sintering behavior and densification process were systematically investigated in this study. With the modified powders, debound parts with a more homogeneous and smaller pore size distribution were fabricated. Also, a higher density and greater flexural strength were achieved in the sintered parts fabricated using the modified powders.

关键词： ceramic materials zirconia injection molding oleic acid sintering

Sintering kinetics involving grain growth and densification of Mg-PSZ nanopowders

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Journal of Iron and Steel Research International 2022年第7期29卷 1138-1144页

作者： Yi-ming She Jie-fu Lang Di An Chao-wei Si Xu-dong Luo zhi-peng xie Jie-gang You School of Materials and Metallurgy University of Science and Technology LiaoningAnshan 114051LiaoningChina Institute of Advanced Structures Beijing Institute of TechnologyBeijing 100081China State Key Lab of New Ceramics and Fine Processing School of Materials Science and EngineeringTsinghua UniversityBeijing 100084China

Sintering kinetics have been found to be effective in judging the evolution of *** using magnesium oxide-partially stabilized zirconia(Mg-PSZ)powder prepared by co-precipitation as raw materials,the evolution of densification and grain growth for Mg-PSZ ceramics were *** results indicated that the densification of samples was mainly controlled by grain boundary diffusion in intermediate sintering *** the sintering process,the grain growth mechanisms included normal grain growth,abnormal grain growth and solid solution drag-controlled grain ***,the apparent activation energy for grain growth of Mg-PSZ ceramics is lower than that of ZrO_(2)–Y_(2)O_(3)ceramics in the solid solution drag-controlled grain grow process,which will cause grain to grow *** sintering kinetics and microstructure of Mg-PSZ ceramics were studied,and the kinetic equation of grain growth at different temperatures was *** results show that the strength difference between Mg-PSZ and yttrium oxide-stabilized zirconia is closely related to the easy grain growth of Mg-PSZ ceramics.

关键词： Magnesium oxide-partially stabilized zirconia Sintering kinetics Grain growth mechanism Densification mechanism Sizing nozzle

Thickness and sp3 bond modulation of（Ti/tetrahedral amorphous carbon）_n multilayer coatings

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Tungsten 2025年第1期7卷 152-160页

作者： zhi-Jun xie Jia-Lin Li Ling Gong Xiang-Li Zhong Hong-Jia Song Jin-Bin Wang National-Provincial Laboratory of Special Function Thin Film Materials School of Materials Science and Engineering Xiangtan University

The durability of wear-resistant tetrahedral amorphous carbon（ta-C） coatings is intimately linked to their thickness and the concentration of *** enhance the lifespan of the coatings,we have prepared a multilayer coating consisting of alternating layers of Ti and ta-C,denoted as（Ti/ta-C）_n,using arc ion plating.A multi-layer structure in conjunction with stage cooling is employed to enhance the thickness and promote *** results indicate that the ID/IGvalue,representing the ratio of the intensity of the D peak to that of the G peak in Raman spectroscopy,decreases from 0.85 when no stage cooling is applied to 0.35 when stage cooling is employed,suggesting an enhancement in the fraction of sp3bonds within the *** obtained（Ti/ta-C）_n multilayer coating without peeling off has a maximum thickness of 1.14 μm,which is almost double that of the ta-C coating single layer *** the same time,the coating has a low coefficient of friction,down to 0.069,and maintains excellent friction properties with a wear rate of 3.4×10-6mm3·N-1·*** results conclusively show that the preparation technology can enhance both thickness and sp3bonding in ta-C coatings,significantly expanding their utility across tools,molds,and precision engineering components.

关键词： Arc ion plating Multilayer structure sp3 bond Ta-C coating Wear resistance

基于DMD的阿达玛变换型近红外光谱仪快速处理系统设计与实现

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光谱学与光谱分析 2025年第1期45卷 133-138页

作者：王硕谢振坤魏志鹏长春理工大学高功率半导体激光国家重点实验室吉林长春130022 长春理工大学中山研究院广东中山528437

数字微镜器件(DMD)的近红外光谱仪,具有波长重复性好、分辨率高和抗振动性好等优点,广泛应用于食品安全和农业生产等领域的研究。随着DMD的微小型近红外光谱仪发展逐渐趋于成熟,仪器的成本和性能仍然是研发的关键。尽管大部分将重点放... 详细信息

数字微镜器件(DMD)的近红外光谱仪,具有波长重复性好、分辨率高和抗振动性好等优点,广泛应用于食品安全和农业生产等领域的研究。随着DMD的微小型近红外光谱仪发展逐渐趋于成熟,仪器的成本和性能仍然是研发的关键。尽管大部分将重点放在了软件开发和检测方法的研究,而仪器硬件的处理速度至关重要。只有确保光谱仪能够快速准确的采集并传输数据,才能有效实现光谱分析。在多数研究中,阿达玛矩阵的生成和解码工作通常由上位机完成,并通过FLASH存储的方式导入模板。这种方式可能会限制采集一幅完整光谱数据的时间效率。为了提高光谱采集速度和信噪比,提出一种高速驱动DMD和快速数据采集的方法,并基于DMD微小型近红外光谱仪设计一套硬件电路系统。采用现场可编辑门阵列(FPGA)和ARM的架构,创新性地实现了奇偶阿达玛模板的生成与解码过程在嵌入式系统底层执行,加快了光谱分析的速度并提高信噪比。通过与市面上DMD型光谱仪对比,研究结果显示,所研发的光谱仪完成单次光谱的采集时间仅需214 ms,相比商用DMD型光谱仪,采集效率提升了4倍。在同等3 s的采集时间内,所研发光谱仪的信噪比为4600,相比商用DMD型光谱仪,信噪比提升了1.5倍。通过所研发的光谱仪对油菜籽样品进行光谱扫描,分析了油菜籽的脂肪、蛋白质和水分的含量,并采用偏最小二乘回归(PLSR)建立了相应的模型。油菜籽脂肪含量的校正相关系数为0.9865、预测相关系数为0.9672;蛋白质含量的校正相关系数为0.9854、预测相关系数系数为0.9636;水分含量的校正相关系数为0.9875、预测相关系数为0.9614。模型评估的结果表明,该光谱仪能够满足油菜籽成分检测的需求,验证该光谱仪在商业领域具有重要的应用价值。

关键词：数字微镜器件近红外光谱仪阿达玛信噪比嵌入式油菜籽

基于遥爪型大分子交联剂的动态化学交联水凝胶的黏弹性质

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功能高分子学报 2018年第3期31卷 241-247页

作者：叶志鹏谢曼青谢家礼赵传壮宁波大学材料科学与化学工程学院宁波市特种高分子材料重点实验室浙江宁波315211

以壳聚糖为主链,以双端苯醛基聚乙二醇(DF-PEG)为交联剂,以希夫碱为动态交联键制备了动态化学交联水凝胶,通过改变大分子交联剂的分子量和浓度调控凝胶网络结构。以旋转流变仪的动态频率扫描和稳态剪切为主要手段,研究了凝胶结构对凝胶... 详细信息

以壳聚糖为主链,以双端苯醛基聚乙二醇(DF-PEG)为交联剂,以希夫碱为动态交联键制备了动态化学交联水凝胶,通过改变大分子交联剂的分子量和浓度调控凝胶网络结构。以旋转流变仪的动态频率扫描和稳态剪切为主要手段,研究了凝胶结构对凝胶模量、松弛时间、剪切增稠程度的影响。结果表明:DF-PEG的分子量和浓度会影响凝胶网络内弹性活性链的密度从而影响模量、松弛时间,而凝胶剪切增稠程度与弹性活性链密度密切相关。

关键词：动态化学交联凝胶遥爪聚合物线性流变非线性流变剪切增稠

STIL enhances the development of lung adenocarcinoma by regulating the glycolysis pathway

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Oncology Research 2025年第1期33卷 123-132页

作者： LEI WANG XIANJIN xie Department of Respiratory Medicine Jen Ching Memorial HospitalSuzhou215300China Department of Respiratory Medicine Shandong Provincial Third HospitalJinan250010China

Background:To investigate SCL/TAL 1 interrupting locus(STIL)’s role and prognostic significance in lung adenocarcinoma(LUAD)progression,we examined STIL and E2 promoter binding factor 1(E2F1)expression and their impacts on LUAD prognosis using Gene Expression Profiling Interactive Analysis(GEPIA).Methods:Functional assays including CCK-8,wound-healing,5-ethynyl-2-deoxyuridine(EdU),Transwell assays,and flow cytometry,elucidated STIL and E2F1’s effects on cell viability,proliferation,apoptosis,and *** set enrichment analysis(GSEA)identified potential pathways,while metabolic assays assessed glucose ***:Our findings reveal that STIL and E2F1 are overexpressed in LUAD,correlating with adverse *** enhances cell proliferation,migration,and invasion,and suppresses apoptosis,activating downstream of *** E2F1 reversed the promotion effect of the STIL overexpression on cell viability and ***,STIL modulates glycolysis,influencing glucose consumption,lactate production,and energy balance in LUAD ***:Our model,incorporating STIL,age,and disease stage,robustly predicts patient prognosis,underscored STIL’s pivotal role in LUAD pathogenesis through metabolic *** comprehensive approach not only confirms STIL’s prognostic value but also highlights its potential as a therapeutic target in LUAD.

关键词： SCL/TAL1 interrupting locus(STIL) Lung adenocarcinoma E2 promoter binding factor 1 Glycolysis

Local-contrastive-learning machine with both generalization and adversarial robustness: A statistical physics analysis

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Science China(Physics,Mechanics & Astronomy) 2025年第1期Mechanics & Astronomy) .卷 109-123页

作者： Mingshan xie Yuchen Wang Haiping Huang PMI Lab School of Physics Sun Yat-sen University Guangdong Provincial Key Laboratory of Magnetoelectric Physics and Devices Sun Yat-sen University

Distinct from human cognitive processing, deep neural networks trained by backpropagation can be easily fooled by adversarial examples. To design a semantically meaningful representation learning, we discard backpropagation, and instead, propose a local contrastive learning, where the representations for the inputs bearing the same label shrink(akin to boson) in hidden layers,while those of different labels repel(akin to fermion). This layer-wise learning is local in nature, being biologically plausible.A statistical mechanics analysis shows that the target fermion-pair-distance is a key parameter. Moreover, the application of this local contrastive learning to MNIST benchmark dataset demonstrates that the adversarial vulnerability of standard perceptron can be greatly mitigated by tuning the target distance, i.e., controlling the geometric separation of prototype manifolds.

关键词： machine learning statistical mechanics adversarial robustness neural networks