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基于一步法制备的高拉伸性二硫键交联环氧化天然橡胶
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作者 刘杰 翟荣洋 +3 位作者 孙鹏 郭小仟 雷巍巍 施德安 《高分子材料科学与工程》 北大核心 2025年第5期47-57,共11页
目前,受共价交联点对橡胶分子链运动的限制,采用硫磺、过氧化物等硫化剂制备的橡胶存在断裂伸长率低的问题,难以应用于高度拉伸或高韧性需求的场合。文中通过一步法在橡胶中引入键能居于共价键和氢键之间的脂肪族二硫键作为交联剂,制备... 目前,受共价交联点对橡胶分子链运动的限制,采用硫磺、过氧化物等硫化剂制备的橡胶存在断裂伸长率低的问题,难以应用于高度拉伸或高韧性需求的场合。文中通过一步法在橡胶中引入键能居于共价键和氢键之间的脂肪族二硫键作为交联剂,制备了二硫键交联的环氧化天然橡胶体系,研究了二硫键含量与环氧化天然橡胶物理力学性能之间的关系。研究表明,随二硫键交联剂含量增加,橡胶交联密度和弹性模量增大,溶胀比降低。同时,随二硫键交联点含量增加,抗蠕变能力增强,应力松弛变慢。加入1.8 phr小分子交联剂,橡胶拉伸强度达4.88 MPa,断裂伸长率达1065%。加入2.8 phr小分子交联剂,橡胶拉伸强度达5.29 MPa,断裂伸长率达842%。经过3次重复加工后,橡胶的拉伸强度均可达到3 MPa左右,断裂伸长率接近300%。 展开更多
关键词 环氧化天然橡胶 脂肪族二硫键 一步法 高拉伸性
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基于刚性基团与多重氢键协同的高强韧自修复环氧化天然橡胶
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作者 刘杰 孙鹏 +4 位作者 郭小仟 雷巍巍 吴河生 黄湘 施德安 《高分子学报》 北大核心 2025年第12期2381-2395,共15页
氢键由于具有动态属性在自修复橡胶弹性体领域广泛应用.目前报道的单一氢键交联自修复橡胶受限于氢键的低结合能,普遍存在拉伸强度较低(通常低于3 MPa)的问题.尽管氢键/共价键双网络结构可在一定程度上提高拉伸强度,但共价键的引入会削... 氢键由于具有动态属性在自修复橡胶弹性体领域广泛应用.目前报道的单一氢键交联自修复橡胶受限于氢键的低结合能,普遍存在拉伸强度较低(通常低于3 MPa)的问题.尽管氢键/共价键双网络结构可在一定程度上提高拉伸强度,但共价键的引入会削弱材料的自修复能力和可再加工性.本工作通过在环氧化天然橡胶(ENR)中引入含刚性基团的多重氢键交联点,系统研究了该类交联点含量对ENR物理机械性能、自修复性能及抗裂纹性能的影响.结果表明,该橡胶材料的断裂伸长率可超过1200%,拉伸强度可达10.38 MPa,断裂能达46.26 MJ/m^(3),并具备一定的自修复能力.此外,该类氢键交联结构还显著提升了ENR的抗裂纹性能.本工作不仅为高强韧自修复弹性体的设计提供了新思路,而且为抗裂纹材料的发展提供了参考. 展开更多
关键词 环氧化天然橡胶 氢键 刚性基团 高强度高韧性 自修复
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弹性体裂纹扩展表征方法的研究进展
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作者 郭小仟 黄湘 +3 位作者 吴河生 孙鹏 雷巍巍 刘杰 《高分子材料科学与工程》 北大核心 2025年第7期172-180,共9页
如何预测和表征弹性体裂纹扩展是弹性体领域的重要问题。文中对弹性体裂纹扩展表征方法和抗裂纹能力提升策略进行了总结,对各裂纹扩展表征方法的适用材料进行了归纳,并探讨了断裂基本功的影响因素,对预制裂纹缺口的选择提供了方案。结... 如何预测和表征弹性体裂纹扩展是弹性体领域的重要问题。文中对弹性体裂纹扩展表征方法和抗裂纹能力提升策略进行了总结,对各裂纹扩展表征方法的适用材料进行了归纳,并探讨了断裂基本功的影响因素,对预制裂纹缺口的选择提供了方案。结合刚性材料的表征方法,进一步对弹性体裂纹研究提出展望,以期为后续弹性体研究提供借鉴。 展开更多
关键词 弹性体 裂纹扩展 断裂基本功
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The Ce-modified biochar for efficient removal of methylene blue dye:Kinetics,isotherms and reusability studies 被引量:1
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作者 Shuaishuai Zhang Xinan sun +3 位作者 Qingwen Luo Lin Chi peng sun Lianke Zhang 《Chinese Journal of Chemical Engineering》 2025年第1期57-65,共9页
Exploring modification methods for enhancing the adsorption performance of biochar-based adsorbents for effective removal of methylene blue(MB),biochar-loaded CeO_(2)nanoparticles(Ce/BC)were synthesized by pomelo peel... Exploring modification methods for enhancing the adsorption performance of biochar-based adsorbents for effective removal of methylene blue(MB),biochar-loaded CeO_(2)nanoparticles(Ce/BC)were synthesized by pomelo peels through co-precipitation combined with the pyrolysis method.Ce/BC showed a higher specific surface area and disorder degree than that of BC.The 0.5Ce/BC(mass ratio of Ce(NO_(3))_(3)·6H_(2)O/BC=0.5/1)showed the best performance to adsorption of MB solution at different reaction conditions(MB concentration,Ce/BC composites dosage,and initial pH).Adsorption kinetics and equilibrium isotherms were well-described with a pseudo-first-order equation and Langmuir model,respectively.In addition,the maximum adsorption capacity of 0.5Ce/BC for MB was 105.68 mg·g^(-1)at 328 K.The strong adsorption was attributed to multi-interactions including pore filling,π-πinteractions,electrostatic interaction,and hydrogen bonding between the composites and MB.This work demonstrated that the modified pomelo peels biochar,as a green promising material with cost-effectiveness,exhibited a great potential for broad application prospectively to dyeing-contaminated wastewater treatment. 展开更多
关键词 CeO_(2) BIOCHAR Methylene blue ADSORPTION Stability
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Full conjugated poly(1,4-phenyldiazo porphyrin cobalt)covalent organic framework with D-π-A structure enhancing bifunctional oxygen catalytic performance 被引量:1
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作者 Yanqiong Zhuang Yinggang sun +4 位作者 Likai Wang peng sun Jigang Wang penghao Zhang Zhongfang Li 《Journal of Energy Chemistry》 2025年第5期214-224,共11页
Fully conjugated covalent organic frameworks(COFs)are widely used in electrocatalysis.The COF with-ph-NH_(2)edge poly(1,4-phenyldiazo porphyrin cobalt)(A-PpazoPorCo)is synthesized by adjusting the molar ratio of the r... Fully conjugated covalent organic frameworks(COFs)are widely used in electrocatalysis.The COF with-ph-NH_(2)edge poly(1,4-phenyldiazo porphyrin cobalt)(A-PpazoPorCo)is synthesized by adjusting the molar ratio of the reaction material,and exhibits high delocalization energy to significantly enhance thermal stability.The nitrogen in the azo bond improves the adsorption capacity for ORR and OER catalytic intermediates,while the-ph-NH_(2)group further increases the electron cloud density at the Co-N_(4)center in A-PpazoPorCo.Density functional theory(DFT)calculations reveal that the strong electron-donating-ph-NH_(2)groups and the electron-donating azo bonds form an electron donor-π-electron acceptor(D-π-A)structure,which further enhances the electron cloud density.The strongπ-πinteraction between A-PpazoPorCo and three-dimensional graphene(3D-G)significantly boosts the oxygen catalytic performance of the A-PpazoPorCo/3D-G.The catalytic ORR half-wave potential(E_(1/2))of A-PpazoPorCo/3D-G can reach 0.880 V vs.RHE.The total overpotential(ΔE=E_(j=10)-E_(1/2))is 0.617 V,demonstrating excellent bifunctional oxygen catalytic performance.The efficient oxygen catalytic performance indicates that A-PpazoPorCo/3D-G has the potential for application in fuel cells cathodes and overall water splitting anodes. 展开更多
关键词 Bifunctional oxygen reaction catalyst Fully conjugated COFs Azo-bridged porphyrin cobalt Electron donor groups π-πinteraction
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Image Super-Resolution Reconstruction Based on the DSSTU-Net Model 被引量:1
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作者 Bonan Yu Taiping Mo +2 位作者 Qi Ma Qiumei Li peng sun 《Computers, Materials & Continua》 2025年第4期1057-1078,共22页
Super-resolution(SR)reconstruction addresses the challenge of enhancing image resolution,which is critical in domains such as medical imaging,remote sensing,and computational photography.High-quality image reconstruct... Super-resolution(SR)reconstruction addresses the challenge of enhancing image resolution,which is critical in domains such as medical imaging,remote sensing,and computational photography.High-quality image reconstruction is essential for enhancing visual details and improving the accuracy of subsequent tasks.Traditional methods,including interpolation techniques and basic CNNs,often fail to recover fine textures and detailed structures,particularly in complex or high-frequency regions.In this paper,we present Deep Supervised Swin Transformer U-Net(DSSTU-Net),a novel architecture designed to improve image SR by integrating Residual Swin Transformer Blocks(RSTB)and Deep Supervision(DS)mechanisms into the U-Net framework.DSSTU-Net leverages the Swin Transformer’s multi-scale attention capabilities for robust feature extraction,while DS at various stages of the network ensures better gradient propagation and refined feature learning.The ST block introduces a hierarchical self-attention mechanism,allowing the model to capture both local and global context,which is crucial for high-quality SR tasks.Moreover,DS applied at multiple layers in the decoder enables direct supervision on intermediate feature maps,accelerating convergence and improving performance.The DSSTU-Net architecture was rigorously evaluated on the DIV2K,LSDIR,SET5,and SET14 datasets,demonstrating its superior ability to generate high-quality images.Furthermore,the potential applications of this model extend beyond image enhancement,with promising use cases in medical imaging,satellite imagery,and industrial inspection,where high-quality image reconstruction plays a crucial role in accurate diagnostics and operational efficiency.This work provides a reference method for future research on advanced image restoration techniques. 展开更多
关键词 SR DSSTU-Net RSTB DS
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全共轭酞菁配合物类催化剂的制备及催化氧反应双功能性能提升
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作者 庄延琼 孙迎港 +1 位作者 孙鹏 李忠芳 《化学进展》 北大核心 2025年第9期1290-1300,共11页
酞菁过渡金属大环配合物已广泛应用于能量转化与储存等相关的电化学反应过程,包括催化氧还原反应(ORR)和析氧反应(OER)等,其良好的催化氧反应双功能性能引起了广泛关注。本文主要综述了金属酞菁类催化剂的制备方法及当前研究进展,综述... 酞菁过渡金属大环配合物已广泛应用于能量转化与储存等相关的电化学反应过程,包括催化氧还原反应(ORR)和析氧反应(OER)等,其良好的催化氧反应双功能性能引起了广泛关注。本文主要综述了金属酞菁类催化剂的制备方法及当前研究进展,综述了影响金属酞菁类催化剂性能的因素,如:金属酞菁的结构、载体、中心金属离子及双金属离子的协同效应和边缘修饰基团的影响等。分析了全共轭结构对其热稳定性和催化性能提升的影响;聚合金属酞菁配合物和三维石墨烯的π-π相互作用有利于提高催化活性和耐久性;两种金属之间的协同效应和边缘修饰的供电子基团可以提升催化性能。 展开更多
关键词 催化氧反应双功能催化剂 过渡金属大环配合物 全共轭COFs Π-Π相互作用 协同效应 边缘修饰基团的影响
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Comparing the Effect of CHL Background on Chinese Receptive Vocabulary Breadth Between Indonesian and Thai CS/FL Learners:A Mixed-Methods Study
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作者 Haiwei Zhang peng sun +1 位作者 Winda Widiawati Yaowaluk Bianglae 《Chinese Journal of Applied Linguistics》 2025年第2期241-265,321,共26页
The advantage of Chinese-as-a-heritage-language(CHL)learners in acquiring Chinese has been widely recognized.However,it is still unclear whether the effect of CHL background on Chinese receptive vocabulary breadth var... The advantage of Chinese-as-a-heritage-language(CHL)learners in acquiring Chinese has been widely recognized.However,it is still unclear whether the effect of CHL background on Chinese receptive vocabulary breadth varies across different countries.To address this gap,the present study recruited 232 Chinese language learners(half were CHL learners)from Indonesia and Thailand and administered a Chinese vocabulary proficiency test.The results of regression analysis revealed an interaction effect between country and CHL background on vocabulary breadth,with the contribution of CHL background to vocabulary breadth more robust in the Indonesian group than that in the Thai group.Interviews were then conducted to explore the factors that might influence such an interaction effect.Analysis of the interview data found that the influencing factors could be categorized into four themes,including individual differences,family background,Chinese language education and socio-cultural factors.The overall results were discussed within the framework of ecological system theory,and pedagogical implications for CHL learners were proposed. 展开更多
关键词 Chinese as a heritage language Chinese as a second/foreign language vocabulary breadth vocabulary size Thailand Indonesia
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Combination of Astragalus−Salvia and Ophiopogon−Dendrobium herb pairs alleviates Sjögren’s Syndrome via inhibiting the JAK1/STAT3 and PI3K/AKT pathways in NOD/Ltj mice
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作者 peng sun Lili Zhu +6 位作者 Yang Yu Sijing Hu Mengyi Shan Xuan Zhao Xinchang Wang Qiaoyan Zhang Luping Qin 《Chinese Journal of Natural Medicines》 2025年第6期733-741,共9页
Sjögren’s syndrome(SS)is an autoimmune disease characterized primarily by oral and periocular dryness.Astragalus-Salvia(AS)and Ophiopogon-Dendrobium(OD)represent two frequently utilized herb pairs in SS treatmen... Sjögren’s syndrome(SS)is an autoimmune disease characterized primarily by oral and periocular dryness.Astragalus-Salvia(AS)and Ophiopogon-Dendrobium(OD)represent two frequently utilized herb pairs in SS treatment.While the combination of AS-OD herb pairs demonstrates clinical efficacy in alleviating SS symptoms,its underlying mechanism remains unclear.This investigation sought to assess the therapeutic effects and elucidate the potential mechanisms of AS-OD in non-obese diabetic(NOD)/Ltj mice with SS.The study utilized NOD/Ltj mice as SS models,administering AS-OD treatment for 10 weeks at doses of 113.1,226.2,and 339.3 mg·d−1·20 g−1.Results demonstrated that AS-OD improved SS symptoms,evidenced by enhanced salivary flow rate,decreased anti-SSA/Ro and anti-SSB/La antibody levels,increased swimming duration,and reduced lactate(LA)and blood urea nitrogen(BUN)levels in NOD/Ltj mice.AS-OD reduced lymphocyte infiltration,enhanced Aquaporin-5(AQP5)expression in the submandibular gland,decreased inflammatory cytokine levels in the submandibular gland,and reduced the T helper type 17/regulatory T lymphocyte(Th17/Treg)cell ratio in the spleen.Transcriptomic and proteomic analyses indicated AS-OD’s involvement in regulating phosphatidylinositol-3-kinase/protein kinase B(PI3K/AKT)and Janus kinase 3/signal transducer and activator of transcription 3(JAK1/STAT3)pathways,with inhibitory effects validated in both NOD/Ltj mice submandibular gland and A-253 cells.Furthermore,AS-OD enhanced cell viability and reduced A-253 cell apoptosis through the PI3K/AKT pathway.In A-253 cells,AS-OD reduced inflammatory cytokine levels,CXC chemokine ligand 9/10(CXCL9/10),and T-cell chemotaxis by inhibiting the JAK1/STAT3 pathway.AS-OD mitigates SS by suppressing inflammation and immune responses through the PI3K/AKT and JAK1/STAT3 pathways. 展开更多
关键词 Sjgren’s syndrome Astragalus-Salvia herb pair Ophiopogon-Dendrobium herb pair CXCL9 and CXCL10 JAK1/STAT3 PI3K/AKT
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Occurrence,characteristics and removal of microplastics in wastewater treatment plants with different treatment processes
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作者 Yiting Lian Xianwei Wang +2 位作者 peng sun Hua Wang Chengran Fang 《Chinese Journal of Chemical Engineering》 2025年第9期316-326,共11页
The abundance of microplastics(MPs)in wastewater from three wastewater treatment plants(WWTPs)were determined in Hangzhou,Zhejiang Province,China.The MPs abundance was 140-350 particles per litre in the influent and 1... The abundance of microplastics(MPs)in wastewater from three wastewater treatment plants(WWTPs)were determined in Hangzhou,Zhejiang Province,China.The MPs abundance was 140-350 particles per litre in the influent and 10-30 particles per litre in the effluent.Four shapes of MPs in the influent were observed,while mainly only debris was left in the effluent.The percentage of small(<100μm),medium(100-500μm),and large-sized(≥500μm)plastics in the raw leachate of the three WWTPs were 54.3%,8.6%,and 37.1%,28.6%,64.3%,and 7.1%,and 41.4%,24.1%,and 34.5%,respectively.Mainly only the size of≤100μm was left in the effluent of all.The removal efficiencies of MPs in a range of 78.6%to 96.6%were achieved.Polypropylene,polystyrene,polyethylene,polyethylene terephthalate and polyvinyl chloride were the main types and detected in all wastewater samples,accounting for over 75%of all types.The plastic components contained in different industrial wastewater were more complex.The distribution of MPs was significantly positively correlated with most conventional indicators such as chemical oxygen demead,ammonia nitrogen,and total phosphorus,but not with heavy metals.Similar wastewater,different treatment processes,or similar processes but different wastewater(industrial wastewater proportion varied)could all lead to differences in MPs removal.The MPs abundance measured in this experiment was similar to some previous studies,but relatively high.The three WWTPs can discharge up to 6.0×10^(-8)-1.8×10^(-9) plastics of MPs per day,which poses potential ecological risks.This study indicates that the source control of MPs and optimizing the process design of existing WWTPs are crucial for preventing and controlling MPs pollution. 展开更多
关键词 Microplastics ABUNDANCE Removal efficiency Wastewater treatment plant Treatment process
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P2-type low-cost and moisture-stable cathode for sodium-ion batteries
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作者 Xuan Wang peng sun +2 位作者 Siteng Yuan Lu Yue Yufeng Zhao 《Chinese Chemical Letters》 2025年第5期679-684,共6页
Mn-based P2-type oxides are considered as promising cathodes for Na-ion batteries;however,they face significant challenges,including structural degradation when charged at high cutoff voltages and structural changes u... Mn-based P2-type oxides are considered as promising cathodes for Na-ion batteries;however,they face significant challenges,including structural degradation when charged at high cutoff voltages and structural changes upon storing in a humid atmosphere.In response to these issues,we have designed an oxide with co-doping of Cu and Al which can balance both cost and structural stability.The redox reaction of Cu^(2+/3+)can provide certain charge compensation,and the introduction of Al can further suppress the Jahn-Teller effect of Mn,thereby achieving superior long-term cycling performance.The ex-situ XRD testing indicates that Cu/Al co-doping can effectively suppress the phase transition of P2-O2 at high voltage,thereby explaining the improvement in electrochemical performance.DFT calculations reveal a high chemical tolerance to moisture,with lower adsorption energy for H_(2)O compared to pure Na_(0.67)Cu_(0.25)Mn_(0.75)O_(2).A representative Na_(0.67)Cu_(0.20)Al_(0.05)Mn_(0.75)O_(2)cathode demonstrates impressive reversible capacities of 148.7 mAh/g at 0.2 C,along with a remarkable capacity retention of 79.1%(2 C,500 cycles). 展开更多
关键词 Cathode material P2 phase Moisture sensitivity LOW-COST Sodium-ion batteries
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GB/T 1236中的B型试验装置便捷测量研究
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作者 刘基照 任刚 +3 位作者 宋亮 陈健勇 孙鹏 汪义玲 《风机技术》 2025年第6期91-96,共6页
现行通风机性能试验标准GB/T 1236中的B型试验装置在使用时由于有多测点和多工况的要求,行业内普遍存在操作不便、测量效率低等问题。因此,在基于业内常见做法分析的基础上,对该装置的毕托管段、节流机构及采集气路部分进行了研究,并提... 现行通风机性能试验标准GB/T 1236中的B型试验装置在使用时由于有多测点和多工况的要求,行业内普遍存在操作不便、测量效率低等问题。因此,在基于业内常见做法分析的基础上,对该装置的毕托管段、节流机构及采集气路部分进行了研究,并提出相应的改进措施。通过改进的B型试验装置在某一空调机组气动性能测量的应用实例,证明该改进能实现同一风道截面上所有测点压力数据的同时采集和试验工况的电动调节,且减少数据记录和处理工作量,凸显其便捷性优点。 展开更多
关键词 B型试验装置 毕托管段 节流机构 同时采集 电动调节
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Carbon Dots-Modified Hollow Mesoporous Photonic Crystal Materials for Sensitivityand Selectivity-Enhanced Sensing of Chloroform Vapor
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作者 Junchen Liu Ji Liu +9 位作者 Zhipeng Li Liupeng Zhao Tianshuang Wang Xu Yan Fangmeng Liu Xiaomin Li Qin Li peng sun Geyu Lu Dongyuan Zhao 《Nano-Micro Letters》 2025年第4期381-398,共18页
Chloroform and other volatile organic pollutants have garnered widespread attention from the public and researchers,because of their potential harm to the respiratory system,nervous system,skin,and eyes.However,resear... Chloroform and other volatile organic pollutants have garnered widespread attention from the public and researchers,because of their potential harm to the respiratory system,nervous system,skin,and eyes.However,research on chloroform vapor sensing is still in its early stages,primarily due to the lack of specific recognition motif.Here we report a mesoporous photonic crystal sensor incorporating carbon dots-based nanoreceptor(HMSS@CDs-PCs)for enhanced chloroform sensing.The colloidal PC packed with hollow mesoporous silica spheres provides an interconnected ordered macro-meso-hierarchical porous structure,ideal for rapid gas sensing utilizing the photonic bandgap shift as the readout signal.The as-synthesized CDs with pyridinic-N-oxide functional groups adsorbed in the hollow mesoporous silica spheres are found to not only serve as the chloroform adsorption sites,but also a molecular glue that prevents crack formation in the colloidal PC.The sensitivity of HMSS@CDs-PCs sensor is 0.79 nm ppm^(-1)and an impressively low limit of detection is 3.22 ppm,which are the best reported values in fast-response chloroform vapor sensor without multi-signal assistance.The positive response time is 7.5 s and the negative response time 9 s.Furthermore,relatively stable sensing can be maintained within a relative humidity of 20%-85%RH and temperature of 25-55℃.This study demonstrates that HMSS@CDs-PCs sensors have practical application potential in indoor and outdoor chloroform vapor detection. 展开更多
关键词 Carbon dots Photonic crystal sensors Sensitivity-enhanced sensing Selectivity-enhanced sensing Chloroform vapor sensing
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Microstructure evolution and strengthening mechanism of electron beam welded dual-phase Mg-8Li-3Al-2Zn-0.5Y alloy
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作者 Lingfan Yi Jiaxin Yu +9 位作者 Lianmei Wu Yangyang Xu Yuchuan Huang peng sun Qi Li Wenxia Hu Fei Li Yuyan Tang Guohua Wu Wencai Liu 《Journal of Magnesium and Alloys》 2025年第11期5404-5420,共17页
Nearly undamaged joints of electron beam welded(EBW)dual-phase Mg-8Li-3Al-2Zn-0.5Y alloy were achieved with joint coefficients exceeding 95%.All specimens were fractured at the base metal(BM),implying a significant de... Nearly undamaged joints of electron beam welded(EBW)dual-phase Mg-8Li-3Al-2Zn-0.5Y alloy were achieved with joint coefficients exceeding 95%.All specimens were fractured at the base metal(BM),implying a significant departure from conventional fracture modes of welded joints.The fusion zone(FZ)consists of ultrafine acicular α-Mg and equiaxed β-Li,with grain sizes reduced by approximately 90% and 80%,respectively,compared to the base metal.This results in a significant increase in microhardness of about 40%.A unique multiphase mixture was observed in the heat-affected zone(HAZ),which mainly consists of lamellar eutectoid structures,fine precipitates zone,and numerous fine Mg_(3)(Al,Zn)particles.This mixture was transformed from typical Li(Al,Zn)(a common softening phase)undergoing atomic diffusion and solid-state phase transformation during welding.It introduces a synergistic strengthening effect,making the heat-affected zone no longer the weakest part of the joint.This study provides valuable insights into the electron beam welding technology for Mg-Li alloys and offers theoretical support for manufacturing high-quality joints. 展开更多
关键词 Electron beam welding Mg-8Li-3Al-2Zn-0.5Y Microstructure evolution Mechanical properties Strengthening mechanism
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Comparative experimental study of bisphenol A degradation via sulfate radical and electron transfer mechanisms in persulfate-activated advanced oxidation processes
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作者 Jian Fan Jia-long Li +4 位作者 Bing-qian Deng Jie-xin Wang Wen-bin An Yu-mei Li peng sun 《Water Science and Engineering》 2025年第3期288-300,共13页
Addressing the growing challenge of water contamination,this study comparatively evaluated a persulfate(PDS)system activated by nonradical nitrogen-doped carbon nanotubes(N-CNTs)versus a PDS system activated by radica... Addressing the growing challenge of water contamination,this study comparatively evaluated a persulfate(PDS)system activated by nonradical nitrogen-doped carbon nanotubes(N-CNTs)versus a PDS system activated by radical-based iron(Fe^(2+)),both used for the degradation of bisphenol A(BPA).The N-CNTs/PDS system,driven by the electron transfer mechanism,achieved remarkable 90.9%BPA removal within 30 min at high BPA concentrations,significantly outperforming the Fe^(2+)/PDS system,which attained only 38.9%removal.The N-CNTs/PDS system maintained robust degradation efficiency across a wide range of BPA concentrations and exhibited a high degree of resilience in diverse water matrices.By directly abstracting electrons from BPA molecules,the N-CNTs/PDS system effectively minimised oxidant wastage and mitigated the risk of secondary pollution,ensuring efficient utilisation of active sites on N-CNTs and sustaining a high catalytic rate.The formation of the N-CNTs-PDS^(*)complex significantly enhanced BPA degradation and mineralisation,thereby optimising PDS consumption.These findings highlight the unparalleled advantages of the N-CNTs/PDS system in managing complex wastewater,offering a promising and innovative solution for treating complex industrial wastewater and advancing environmental remediation efforts. 展开更多
关键词 Bisphenol A degradation Advanced oxidation processes(AOPs) Electron transfer mechanism Nitrogen-doped carbon nanotubes Water environment adaptability
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Facile synthesis copper-modified titania(Cu/TiO_(2))nanoparticles for high-efficiency Congo red adsorption
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作者 Shuaishuai Zhang Qingwen Luo +3 位作者 Xinan sun Lin Chi peng sun Lianke Zhang 《Chinese Journal of Chemical Engineering》 2025年第5期87-94,共8页
Pure TiO_(2)and copper-modified titania(Cu/TiO_(2))nanoparticles were synthesized through sol gel combined with the pyrolysis method for the removal of Congo red(CR)in wastewater treatment.Surface morphology and struc... Pure TiO_(2)and copper-modified titania(Cu/TiO_(2))nanoparticles were synthesized through sol gel combined with the pyrolysis method for the removal of Congo red(CR)in wastewater treatment.Surface morphology and structural evaluation utilized XRD,TEM,Raman,FTIR and BET techniques.Cu/TiO_(2)showed rich defects and a higher specific surface area than that of TiO_(2).The 1Cu/TiO_(2)(molar ratio Cu/TiO_(2)of 1/100)showed the best performance to adsorption of CR solution at different reaction conditions(contact duration,CR concentration,adsorbent dose,temperature,and initial pH).Adsorption kinetics and equilibrium isotherms were well-described with a pseudo-second-order kinetics and Freundlich model,respectively.The negative ΔG indicates stable adsorption of CR on the Cu/TiO_(2)surface.The adsorption efficiency only decreases by 6%after 5 cycles of adsorption regeneration.The successful synthesis of Cu/TiO_(2)offers a new possibility to address the problems related to CR dye from aqueous solutions. 展开更多
关键词 Cu/TiO_(2)nanoparticles Congo red Adsorption behavior Stability
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Innovative rotary swaging method drives high performance of n-type Bi_(2)(Te,Se)_(3)thermoelectrics
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作者 Liya Miao Xiang Lu +11 位作者 Qiang Zhang Xiaojian Tan Lidong Chen Kaikai Pang Ruyuan Li Qianqian sun Min Wang peng sun Jiehua Wu Guoqiang Liu Zhenlun Song Jun Jiang 《Journal of Materials Science & Technology》 2025年第20期114-122,共9页
The thermoelectric transport of n-type Bi_(2)Te_(3) heavily depends on grain alignment,causing perfor-mance limitations that severely restrict the demand for low-grade waste heat recovery.Here,the n-type Bi_(2)Te_(2.7... The thermoelectric transport of n-type Bi_(2)Te_(3) heavily depends on grain alignment,causing perfor-mance limitations that severely restrict the demand for low-grade waste heat recovery.Here,the n-type Bi_(2)Te_(2.7)Se_(0.3) material with a certain textured structure is prepared by an innovative rotary swag-ing method.It is found that various defects including Te vacancies,dislocations,and grain boundaries significantly strengthen the phonon scattering.With an obviously suppressed thermal conductivity and well-maintained carrier mobility,the obtained rods extending up to several tens of centimeters achieve a peak ZT of 1.2 at 450 K and an average ZT of 1.0(300-550 K),with Vickers hardness and compressive strength increased to 0.42 GPa and 52.6 MPa,respectively.Moreover,the assembled 17-pair thermoelec-tric module achieves a competitive conversion efficiency of up to 6.3% and a high output power of 0.93 W at a temperature difference of 250 K.This study develops an effective strategy for synergistically en-hancing the thermoelectric and mechanical properties of n-type Bi_(2)(Te,Se)_(3). 展开更多
关键词 Bi_(2)(TeSe)_(3) Rotary swaging Evolutionary microstructure Thermoelectric module
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Ti_(3)C_(2)T_(x) Composite Aerogels Enable Pressure Sensors for Dialect Speech Recognition Assisted by Deep Learning
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作者 Yanan Xiao He Li +8 位作者 Tianyi Gu Xiaoteng Jia Shixiang sun Yong Liu Bin Wang He Tian peng sun Fangmeng Liu Geyu Lu 《Nano-Micro Letters》 2025年第5期1-15,共15页
Wearable pressure sensors capable of adhering comfortably to the skin hold great promise in sound detection.However,current intelligent speech assistants based on pressure sensors can only recognize standard languages... Wearable pressure sensors capable of adhering comfortably to the skin hold great promise in sound detection.However,current intelligent speech assistants based on pressure sensors can only recognize standard languages,which hampers effective communication for non-standard language people.Here,we prepare an ultralight Ti_(3)C_(2)T_(x)MXene/chitosan/polyvinylidene difluoride composite aerogel with a detection range of 6.25 Pa-1200 k Pa,rapid response/recovery time,and low hysteresis(13.69%).The wearable aerogel pressure sensor can detect speech information through the throat muscle vibrations without any interference,allowing for accurate recognition of six dialects(96.2%accuracy)and seven different words(96.6%accuracy)with the assistance of convolutional neural networks.This work represents a significant step forward in silent speech recognition for human–machine interaction and physiological signal monitoring. 展开更多
关键词 Pressure sensor Wearable sensor Ti_(3)C_(2)T_(x) composite aerogel Dialect speech recognition
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Programmable Hierarchical Kirigami Through Controlling Local Cuts
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作者 Han Pan peng sun +1 位作者 Lu Dai Rui Xiao 《Acta Mechanica Solida Sinica》 2025年第5期825-833,共9页
Kirigami,through introducing cuts into a thin sheet,can greatly improve the stretchability of structures and also generate complex patterns,showing potentials in various applications.Interestingly,even with the same c... Kirigami,through introducing cuts into a thin sheet,can greatly improve the stretchability of structures and also generate complex patterns,showing potentials in various applications.Interestingly,even with the same cutting pattern,the mechanical response of kirigami metamaterials can exhibit significant differences depending on the cutting angles in respect to the loading direction.In this work,we investigate the structural deformation of kirigami metamaterials with square domains and varied cutting angles of 0°and 45°.We further introduce a second level of cutting on the basis of the first cutting pattern.By combining experiments and finite element simulations,it is found that,compared to the commonly used 0°cuts,the two-level kirigami metamaterials with 45°cuts exhibit a unique alternating arrangement phenomenon of expanded/unexpanded states in the loading process,which also results in distinct stress–strain response.Through tuning the cutting patterns of metamaterials with 45°cuts,precise control of the rotation of the kirigami unit is realized,leading to kirigami metamaterials with encryption properties.The current work demonstrates the programmability of structural deformation in hierarchical kirigami metamaterials through controlling the local cutting modes. 展开更多
关键词 Kirigami metamaterials Hierarchical cuts Programmable structure Buckling instability
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Clinical Observation on the Management of Gestational Heart Failure and Delivery Outcomes
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作者 Hongjie Li Chenxi Li +8 位作者 peng sun Yuxing Zhai Li Wang Jie Cui Yanlin Mu Jiebing Han Wei Yuan Xinmei Hu Dapan Liang 《Journal of Clinical and Nursing Research》 2025年第1期231-235,共5页
Objective: This study focuses on the clinical observation of the impact of different treatment methods for gestational heart failure on delivery outcomes. Method: A total of 160 pregnant women with heart failure admit... Objective: This study focuses on the clinical observation of the impact of different treatment methods for gestational heart failure on delivery outcomes. Method: A total of 160 pregnant women with heart failure admitted to our hospital between October 2020 and October 2021 were selected as the study subjects. They were categorized based on delivery mode, delivery timing, heart failure control time, and cardiac function status. The delivery outcomes of the different groups were then compared. Result: In terms of delivery methods, the rate of neonatal asphyxia was higher following vaginal delivery than cesarean section. Regarding delivery timing, the neonatal mortality rate was lower for cesarean sections performed at 32-36 + 6 weeks compared to those conducted at 37-39 + 6 weeks. With respect to heart failure control time, the rates of neonatal asphyxia and pulmonary hyaline membrane disease were lower in the ≤ 48- hour group than in the > 48-hour group. From the perspective of cardiac function status, patients with cardiac function I- II exhibited relatively lower rates of neonatal asphyxia and perinatal mortality compared to those with cardiac function III-IV. The observed differences were statistically significant (P < 0.05). Conclusion: For patients with gestational heart failure, cesarean section is the recommended mode of delivery, with the optimal timing being between 32 and 36+6 weeks of pregnancy. During cesarean section, the timing of delivery should be carefully selected based on the mother’s cardiac function status. 展开更多
关键词 PREGNANCY Heart failure management Delivery method Clinical observation
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