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High performance thermally conductive biobased polyamide composites for heat resistant triboelectric nanogenerators
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作者 Wenwen Zhang Zekun Zhao +5 位作者 Haiyang Zhang Jiao Gao Jian Liu Zhenhua Zhou Qingbao Guan Zhengwei You 《Science China Chemistry》 2026年第2期918-923,共6页
Triboelectric nanogenerators(TENGs)are a feasible solution to the energy shortage.As a high performance engineering thermoplastic,polyamides(PAs)have often been used as triboelectric materials of TENGs.However,most ex... Triboelectric nanogenerators(TENGs)are a feasible solution to the energy shortage.As a high performance engineering thermoplastic,polyamides(PAs)have often been used as triboelectric materials of TENGs.However,most existing PAs are synthesized from petroleum-based monomers,and their production processes involve greenhouse gas emissions,which conflict with the sustainable development of TENGs.Accordingly,the research on biobased PAs has attracted increasing attention.Herein,heat-resistant semi-aromatic polyamide(HR-PA)was designed and synthesized from terephthalic acid,butylenediamine,and biobased pentanediamine.HR-PA exhibited outstanding thermal properties in terms of glass transition temperature(T_(g)~130℃),melting point(T_(m)~308℃)and initial decomposition temperature at weight loss of 5%(T_(d)^(5wt%)~436℃).The heat-resistant triboelectric nanogenerator(HR-TENG)was fabricated with HR-PA and high thermal conductivity filler hexagonal boron nitride(h-BN).Introduction of h-BN with good thermal dissipation,the resultant HR-TENG possessed excellent electronic output performances at elevated temperatures,for instance,maximum open-circuit voltage(V_(oc))~90 V,short-circuit current(I_(sc))~8.7μA,and shortcircuit charge(Q_(sc))~30 nC at 150℃.Consequently,this work paves the way for developing HR-TENG that can be integrated into firefighting protective clothing systems for real-time physiological health monitoring. 展开更多
关键词 POLYAMIDE biobased hexagonal boron nitride triboelectric nanogenerator
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Bibliometrics-based Research Hotspots and Development Trends in Eco-hydrology of Dammed Rivers
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作者 CHEN Yingyi FENG Mingming +2 位作者 SHI Guoqiang JIANG Mengyu JIANG Ming 《Chinese Geographical Science》 SCIE CSCD 2023年第6期1153-1164,共12页
Water conservation initiatives satisfy the demand for water supply,electricity generation,irrigation,and flood control.While helping humanity,they have also altered the ecosystem of natural rivers,impacted river ecolo... Water conservation initiatives satisfy the demand for water supply,electricity generation,irrigation,and flood control.While helping humanity,they have also altered the ecosystem of natural rivers,impacted river ecology,disrupted river continuity,and jeopardized the existence of aquatic creatures in rivers.Studying the impacts of dam construction on rivers can enhance our knowledge of river ecological and environmental concerns and help sustain the health of river ecosystems,thereby realizing the harmony between humans and water in both theoretical and practical aspects.This study used bibliometrics and constructed an author-keyword 2-mode matrix network using Co-Occurrence software to identify the hotspots and research trend in eco-hydrology of dammed rivers.We identified‘FLOW’‘SEDIMENT’‘QUALITY’and‘MODEL’as the research hotspots in the ecological impact of dammed rivers,and combined the related literatures,we highlight the research progress in the four directions.Then the research shortcomings and prospect were discussed,including strengthening the monitoring and analysis of critical ecological variables,enhancing the hydrological monitoring density for small rivers,strengthening the research of relationship between eutrophication and zooplankton,establishing multiscale approaches,and combining multi-sources information technologies to improve parameter accuracy in the model research. 展开更多
关键词 dammed river ECO-HYDROLOGY BIBLIOMETRICS ecological impact Co-Occurrence software
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Visible to near-infrared photodetector based on organic semiconductor single crystal
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作者 LI Xiang HU Jin-Han +7 位作者 ZHONG Zhi-Peng CHEN Yu-Zhong WANG Zhi-Qiang SONG Miao-Miao WANG Yang ZHANG Lei LI Jian-Feng HUANG Hai 《红外与毫米波学报》 北大核心 2025年第1期46-51,共6页
Organic semiconductor materials have shown unique advantages in the development of optoelectronic devices due to their ease of preparation,low cost,lightweight,and flexibility.In this work,we explored the application ... Organic semiconductor materials have shown unique advantages in the development of optoelectronic devices due to their ease of preparation,low cost,lightweight,and flexibility.In this work,we explored the application of the organic semiconductor Y6-1O single crystal in photodetection devices.Firstly,Y6-1O single crystal material was prepared on a silicon substrate using solution droplet casting method.The optical properties of Y6-1O material were characterized by polarized optical microscopy,fluorescence spectroscopy,etc.,confirming its highly single crystalline performance and emission properties in the near-infrared region.Phototransistors based on Y6-1O materials with different thicknesses were then fabricated and tested.It was found that the devices exhibited good visible to near-infrared photoresponse,with the maximum photoresponse in the near-infrared region at 785 nm.The photocurrent on/off ratio reaches 10^(2),and photoresponsivity reaches 16 mA/W.It was also found that the spectral response of the device could be regulated by gate voltage as well as the material thickness,providing important conditions for optimizing the performance of near-infrared photodetectors.This study not only demonstrates the excellent performance of organic phototransistors based on Y6-1O single crystal material in near-infrared detection but also provides new ideas and directions for the future development of infrared detectors. 展开更多
关键词 near-infrared photodetector organic semiconductor Y6-1O single crystal spectral response
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A Deep Learning-Based Salient Feature-Preserving Algorithm for Mesh Simplification
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作者 Jiming Lan Bo Zeng +2 位作者 Suiqun Li Weihan Zhang Xinyi Shi 《Computers, Materials & Continua》 2025年第5期2865-2888,共24页
The Quadric Error Metrics(QEM)algorithm is a widely used method for mesh simplification;however,it often struggles to preserve high-frequency geometric details,leading to the loss of salient features.To address this l... The Quadric Error Metrics(QEM)algorithm is a widely used method for mesh simplification;however,it often struggles to preserve high-frequency geometric details,leading to the loss of salient features.To address this limitation,we propose the Salient Feature Sampling Points-based QEM(SFSP-QEM)—also referred to as the Deep Learning-Based Salient Feature-Preserving Algorithm for Mesh Simplification—which incorporates a Salient Feature-Preserving Point Sampler(SFSP).This module leverages deep learning techniques to prioritize the preservation of key geometric features during simplification.Experimental results demonstrate that SFSP-QEM significantly outperforms traditional QEM in preserving geometric details.Specifically,for general models from the Stanford 3D Scanning Repository,which represent typical mesh structures used in mesh simplification benchmarks,the Hausdorff distance of simplified models using SFSP-QEM is reduced by an average of 46.58% compared to those simplified using traditional QEM.In customized models such as the Zigong Lantern used in cultural heritage preservation,SFSP-QEM achieves an average reduction of 28.99% in Hausdorff distance.Moreover,the running time of this method is only 6%longer than that of traditional QEM while significantly improving the preservation of geometric details.These results demonstrate that SFSP-QEMis particularly effective for applications requiring high-fidelity simplification while retaining critical features. 展开更多
关键词 Deep learning mesh simplification quadric error metrics(QEM) salient feature preservation point sampling
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Dynamic Characteristic Testing of Wind Turbine Structure Based on Visual Monitoring Data Fusion
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作者 Wenhai Zhao Wanrun Li +2 位作者 Ximei Li Shoutu Li Yongfeng Du 《Structural Durability & Health Monitoring》 2025年第3期593-611,共19页
Addressing the current challenges in transforming pixel displacement into physical displacement in visual monitoring technologies,as well as the inability to achieve precise full-field monitoring,this paper proposes a... Addressing the current challenges in transforming pixel displacement into physical displacement in visual monitoring technologies,as well as the inability to achieve precise full-field monitoring,this paper proposes a method for identifying the structural dynamic characteristics of wind turbines based on visual monitoring data fusion.Firstly,the Lucas-Kanade Tomasi(LKT)optical flow method and a multi-region of interest(ROI)monitoring structure are employed to track pixel displacements,which are subsequently subjected to band pass filtering and resampling operations.Secondly,the actual displacement time history is derived through double integration of the acquired acceleration data and subsequent band pass filtering.The scale factor is obtained by applying the least squares method to compare the visual displacement with the displacement derived from double integration of the acceleration data.Based on this,the multi-point displacement time histories under physical coordinates are obtained using the vision data and the scale factor.Subsequently,when visual monitoring of displacements becomes impossible due to issues such as image blurring or lens occlusion,the structural vibration equation and boundary condition constraints,among other key parameters,are employed to predict the displacements at unknown monitoring points,thereby enabling full-field displacement monitoring and dynamic characteristic testing of the structure.Finally,a small-scale shaking table test was conducted on a simulated wind turbine structure undergoing shutdown to validate the dynamic characteristics of the proposed method through test verification.The research results indicate that the proposed method achieves a time-domain error within the submillimeter range and a frequency-domain accuracy of over 99%,effectively monitoring the full-field structural dynamic characteristics of wind turbines and providing a basis for the condition assessment of wind turbine structures. 展开更多
关键词 Structural health monitoring dynamic characteristics computer vision vibration monitoring data fusion
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Experimental Research Progress and Transformation Strategy Analysis of Dunhuang Medical Prescriptions
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作者 DONG Xiaofei YANG Xiaoyi LI Yingcun 《Chinese Medicine and Culture》 2025年第4期450-466,共17页
Dunhuang medicine is an important part of Dunhuang studies,boasting rich and comprehensive connotations.It records more than 1,000 Dunhuang medical prescriptions,involving internal,external,gynecological,pediatric,Bud... Dunhuang medicine is an important part of Dunhuang studies,boasting rich and comprehensive connotations.It records more than 1,000 Dunhuang medical prescriptions,involving internal,external,gynecological,pediatric,Buddhist,and Daoist medicine,and has demonstrated good clinical effects.However,the mechanism of action of relevant Dunhuang medical prescriptions is still unclear,existing research lacks systematic review and summarization,which has limited their further development.At the same time,the inheritance,innovation,and transformation of Dunhuang medicine are critical issues for the development of Dunhuang medicine,which has important guiding significance for the future development of Dunhuang medicine.Therefore,this study systematically summarizes the experimental research progress of Dunhuang medical prescriptions[except for those contained in Fu Xing Jue Zang Fu Yong Yao Fa Yao(《辅行诀脏腑用药法要》The Guideline to Use Medicines for Zang-fu)],and seven such prescriptions were selected based on three criteria:well-preserved texts,no prior transmission to the outside world,and having extensive research and clinical application over the past decade.The findings indicate that this type of prescription is applicable to a broad spectrum of diseases and has a promising application prospect in health preservation and disease prevention,as it exerts therapeutic effects through multiple targets and pathways.Based on this,specific strategies for the transformation of Dunhuang characteristic prescriptions were proposed from three aspects:inheritance,innovative development,and transformation strategies,aiming to provide insights for the future development of Dunhuang medical prescriptions. 展开更多
关键词 Dunhuang medicine Dunhuang medical prescriptions Development and transformation of Dunhuang medicine Traditional Chinese medicine
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Development of an efficient and expedited cotyledon protoplast-based transient transformation system in Gossypium hirsutum L.
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作者 WANG Zhicheng CAO Shuaiting +6 位作者 CAI Qiuyan GUAN Zhenhui CHENG Hailiang PENG Fanjia LI Yujun ZUO Dongyun SONG Guoli 《Journal of Cotton Research》 2025年第3期352-364,共13页
Background Cotton is an important crop providing the most natural fibers all over the world. The cotton genomics community has utilized whole genome sequencing data to construct an elite gene pool in which functional ... Background Cotton is an important crop providing the most natural fibers all over the world. The cotton genomics community has utilized whole genome sequencing data to construct an elite gene pool in which functional genes are related to agronomic traits. However, the functional validation of these genes is hindered by time-consuming and inefficient genetic transformation methods. Thus, establishing a transient transformation system of high efficiency is necessary for cotton genomics.Results To improve the efficiency of transient transformation, we used the protoplasts isolated from the etiolated cotyledon as recipient. The enzymatic digestion buffer comprised 1.5%(w/v) cellulase, 0.75%(w/v) macerozyme, and 1% hemicellulase, osmotically buffered with 0.4 mol·L^(-1) mannitol. After 5 h of dark incubation at 25℃, uniform cotton protoplasts were successfully isolated with a yield of 4.6 × 10^(6) protoplasts per gram(fresh weight) and 95% viability. We incubated 100 μL protoplasts(2.5 × 10^(5)·m L^(-1)) with 15 μg plasmid in the solution of 0.4 mol·L^(-1) mannitol and 40% PEG 4000 for 15 min, ultimately achieving an optimal transient transfection efficiency of 71.47%.Conclusions This transient system demonstrated effective utility in cellular biology research through successful applications in subcellular localization analyses, bimolecular fluorescence complementation(Bi FC) verification, and prime editing vector validation. Through systematic optimization, we established an efficient and expedited protoplast-based transient transformation system and successfully applied this platform to cotton functional genomics studies. 展开更多
关键词 Cotton Cotyledon protoplast-based transient transformation Prime editing Protoplast isolation Transient expression
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Nonlinear rheological behavior of asphalt based on large amplitude oscillation shear test under different loading,aging,and modification conditions
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作者 Jiaqiu Xu Zijia Wang +3 位作者 Zepeng Fan Junfu Liu Guoyang Lu Dawei Wang 《Journal of Road Engineering》 2025年第1期48-64,共17页
To reveal the effects of environmental and loading conditions, as well as asphalt properties on the nonlinear rheological behavior of asphalt, the large amplitude oscillation shear(LAOS) test was introduced, and the F... To reveal the effects of environmental and loading conditions, as well as asphalt properties on the nonlinear rheological behavior of asphalt, the large amplitude oscillation shear(LAOS) test was introduced, and the Fourier transform rheology, Lissajous curve method, and the LAOS fatigue test have been applied to investigate the nonlinear rheological behavior of asphalt binders. The research results indicate that a decrease in temperature, an increase in shear frequency and strain level, the introduction of polymer modifiers, and the aging effect of asphalt can significantly increase the nonlinearity of asphalt, manifested by the higher relative magnitude of the third harmonic and zero-strain nonlinear coefficient. For the two polymer modifiers selected in this study, the 4%polyurethane modifier exhibits a higher nonlinear lifting effect than the 4% styrene-butadiene-styrene(SBS). The impact of long-term aging on nonlinear viscoelasticity is observably greater than that of short-term aging. The zero-strain nonlinear coefficient estimated based on the average value method can accurately characterize the nonlinear viscoelasticity of asphalt, which can serve as an effective supplement to the relative magnitude of the third harmonic. All asphalts exhibit shear thinning behavior under the test temperature of 24℃, and the decrease in test temperature, the increase in shear rate and strain level, the introduction of modifiers, and the aging effect of asphalt all exacerbate the shear thinning behavior of asphalt. In addition, the fatigue failure process of asphalt materials is accompanied by an increasing degree of nonlinearity. 展开更多
关键词 Nonlinear viscoelasticity Polymer modified asphalt Large amplitude shear oscillation Rheological behavior Shear thinning
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Stock return forecasting based on the proxy variables of category factors
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作者 Yuan Zhao Xue Gong +1 位作者 Weiguo Zhang Weijun Xu 《Financial Innovation》 2025年第1期3181-3228,共48页
Stock return prediction has been in the spotlight because it involves numerous factors.Improving the accuracy of stock return prediction and quantifying the impact of individual factors on forecasting remain challengi... Stock return prediction has been in the spotlight because it involves numerous factors.Improving the accuracy of stock return prediction and quantifying the impact of individual factors on forecasting remain challenging tasks.Motivated by these challenges,we propose a novel forecasting method that entails proxy variables of category factors and the random forest technique.This new method aims to quantify the information and importance of category factors,thereby enhancing the predictability of stock returns.Specifically,we categorize a large set of return predictors into several category factors.We then utilize the importance of the original variables to construct proxy variables for these category factors.Subsequently,we use the proxy variables to build a random forest model for predicting stock returns.Our empirical analysis results demonstrate that the proposed method effectively quantifies the importance of both the original factors and category factors.Furthermore,we find that the fundamental information factor consistently ranks as the most crucial category factor for stock return forecasting.Additionally,the proposed method exhibits a more robust and prominent prediction performance than competing models such as single-category-factor-based random forest models,dimension-reduction,and forecast-combination methods.Most importantly,the proposed method produces forecast results that can assist investors with understanding stock market dynamics and facilitate higher investment returns. 展开更多
关键词 Return prediction Category factors Dimension reduction Random forest
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Lightweight Human Pose Estimation Based on Multi-Attention Mechanism
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作者 LIN Xiao LU Meichen +1 位作者 GAO Mufeng LI Yan 《Journal of Shanghai Jiaotong university(Science)》 2025年第5期899-910,共12页
Human pose estimation has received much attention from the research community because of its wide range of applications.However,current research for pose estimation is usually complex and computationally intensive,esp... Human pose estimation has received much attention from the research community because of its wide range of applications.However,current research for pose estimation is usually complex and computationally intensive,especially the feature loss problems in the feature fusion process.To address the above problems,we propose a lightweight human pose estimation network based on multi-attention mechanism(LMANet).In our method,network parameters can be significantly reduced by lightweighting the bottleneck blocks with depth-wise separable convolution on the high-resolution networks.After that,we also introduce a multi-attention mechanism to improve the model prediction accuracy,and the channel attention module is added in the initial stage of the network to enhance the local cross-channel information interaction.More importantly,we inject spatial crossawareness module in the multi-scale feature fusion stage to reduce the spatial information loss during feature extraction.Extensive experiments on COCO2017 dataset and MPII dataset show that LMANet can guarantee a higher prediction accuracy with fewer network parameters and computational effort.Compared with the highresolution network HRNet,the number of parameters and the computational complexity of the network are reduced by 67%and 73%,respectively. 展开更多
关键词 human pose estimation attention mechanisms multi-scale feature fusion high-resolution networks
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Cross‑sectional anomalies and conditional asset pricing models based on investor sentiment: evidence from the Chinese stock market
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作者 Zhong‑Qiang Zhou Jiajia Wu +1 位作者 Ping Huang Xiong Xiong 《Financial Innovation》 2025年第1期2984-3007,共24页
This study examines a comprehensive set of 30 cross-sectional anomalies in the Chinese A-share market to investigate whether incorporating investor sentiment as conditioning information enhances the explanatory power ... This study examines a comprehensive set of 30 cross-sectional anomalies in the Chinese A-share market to investigate whether incorporating investor sentiment as conditioning information enhances the explanatory power of asset pricing models.Utilizing a long–short portfolio strategy and Fama–MacBeth cross-sectional regression,we find that trading-based anomalies outnumber accounting-based anomalies in the Chinese market.Our results demonstrate that conditional models significantly outperform their unconditional counterparts.Notably,investor sentiment is crucial for capturing the size anomaly when excluding observations from the COVID-19 pandemic period.Additionally,it substantially improves the ability of conditional Fama–French three-factor models to capture individual anomalies and enhances the return–prediction accuracy of conditional CAPMs.We suggest further investigating high-frequency investor sentiment-based conditional models to anticipate stock price fluctuations during extraordinary public health events. 展开更多
关键词 Cross-sectional anomalies Conditional asset pricing Investor sentiment
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我国老年人数字素养现状与提升路径——基于系统文献综述的研究
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作者 张春华 蒋亦璐 《成人教育》 北大核心 2026年第3期23-31,共9页
提升老年人数字素养是构建终身学习体系与包容性数字社会的关键举措。采用系统文献综述法,全面分析我国老年人数字素养的现状、影响因素及提升路径。研究发现,现有研究构建了涵盖能力、情感、分层、协作及实践导向的多维素养框架,但当... 提升老年人数字素养是构建终身学习体系与包容性数字社会的关键举措。采用系统文献综述法,全面分析我国老年人数字素养的现状、影响因素及提升路径。研究发现,现有研究构建了涵盖能力、情感、分层、协作及实践导向的多维素养框架,但当前老年人数字素养整体水平偏低,个体差异显著,且受个体特征与社会因素共同制约。基于生态系统视角,提出“政策引领—教育赋能—社会协同—技术适配—环境保障”五位一体的提升策略。未来应完善社会支持协同机制,聚焦精细化差异干预,建立动态评估体系,并融合智能技术应用,系统推进老年人数字素养教育,推动“年龄友好型”数字社会建设。 展开更多
关键词 老年人 数字素养 系统文献综述 数字素养框架 提升策略
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硅烷偶联剂改性湿固化聚氨酯的微相分离与耐热性研究
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作者 杨隽永 范陶峰 徐飞 《涂料工业》 北大核心 2026年第3期27-35,共9页
【目的】利用硅烷偶联剂改性湿固化聚氨酯,提升材料耐热性,用于潮湿环境文物保护。【方法】以聚醚多元醇(聚乙二醇和聚四亚甲基醚二醇)和脂肪族异氰酸酯(异佛尔酮二异氰酸酯)为前驱物,仲胺基硅烷偶联剂[三甲氧基3-(苯氨基)丙基硅烷]为... 【目的】利用硅烷偶联剂改性湿固化聚氨酯,提升材料耐热性,用于潮湿环境文物保护。【方法】以聚醚多元醇(聚乙二醇和聚四亚甲基醚二醇)和脂肪族异氰酸酯(异佛尔酮二异氰酸酯)为前驱物,仲胺基硅烷偶联剂[三甲氧基3-(苯氨基)丙基硅烷]为有机硅改性剂,合成了部分硅烷封端的有机硅改性湿固化聚氨酯。通过色差仪、紫外-可见分光光度计、傅立叶变换红外光谱仪、热重分析仪和热氧老化测试等方法对合成的聚氨酯薄膜外观、氢键程度和热稳定性进行表征。【结果】硅烷偶联剂改性湿固化聚氨酯薄膜在可见光范围内透光率为85%~89%,色差<0.4,提高硬段/软段质量分数和仲胺基硅烷偶联剂用量可以分别增加和减小其微相分离。通过FWO和KAS方法计算有机硅改性前后的聚氨酯活化能分别为77.33~99.71 kJ/mol和104.02~127.39 kJ/mol,活化能增加27.8%~34.5%,热降解机制符合扩散模型(D_(1),D_(2)和D_(3))和反应级数模型(F_(n)),受热色差变化减小。【结论】制备的硅烷偶联剂改性湿固化聚氨酯具有无色透明的外观,良好的热稳定性,有望应用在潮湿环境出土的脆弱有机质文物保护方面。 展开更多
关键词 湿固化聚氨酯 硅烷偶联剂 微相分离 热重分析 热降解机制
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中国西北生态脆弱区农户清洁能源使用的脆弱性及影响因素
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作者 李玲燕 王萌萌 +1 位作者 夏浩鸣 段蜜蜜 《干旱区地理》 北大核心 2026年第1期164-175,共12页
加快传统固态能源向清洁能源转型是生态脆弱区农村应对气候变化、强化环境治理和促进区域间可持续发展的必然选择,然而,在被动参与清洁能源改革政策时,中国西北生态脆弱区农户作为经济水平相对落后的群体,普遍存在现代清洁能源设备“改... 加快传统固态能源向清洁能源转型是生态脆弱区农村应对气候变化、强化环境治理和促进区域间可持续发展的必然选择,然而,在被动参与清洁能源改革政策时,中国西北生态脆弱区农户作为经济水平相对落后的群体,普遍存在现代清洁能源设备“改而未用”“基本不用”“低水平使用”的脆弱性现象。为此,采用能源转型的逆向思维,对陕西、甘肃、宁夏和青海地区13个县(区),包括180个村庄的2002户农户进行实地调研,建立“暴露度-敏感性-适应能力”模型综合评估农户清洁能源使用的脆弱性,并利用多元Logit回归模型从“经济-社会-家庭”3个层面分析脆弱性影响因素。结果表明:(1)中国西北生态脆弱区农户清洁能源使用的脆弱性处于低、中、高水平的占比分别为26.12%、46.55%、27.33%,且脆弱性空间异质性显著。(2)耕地面积、能源补贴政策、社会网络、年龄、生计类型、家庭规模等因素均显著影响脆弱性。(3)不同生态脆弱区脆弱性影响因素作用效果存在差异。为此,政府应基于不同生态脆弱区农户清洁能源使用的脆弱性特征,立足区域实际情况,实施差异化的能源补贴政策与推广模式等,以巩固清洁能源改革政策成果。 展开更多
关键词 农户 清洁能源持续使用 脆弱性 “暴露度-敏感性-适应能力”模型 生态脆弱区 中国西北
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《本草纲目》“释名”对于出土文献中药物考释的重要价值
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作者 罗琼 翁晓芳 +1 位作者 刘昕 顾漫 《时珍国医国药》 北大核心 2026年第1期170-174,共5页
通过考释马王堆《五十二病方》《养生方》、阜阳《万物》、《武威汉代医简》及新近成都天回汉墓出土《治六十病和齐汤法》等简帛方书中出现的若干药物异名,并与《本草纲目》的“释名”相参证,认为近年来出土的战国秦汉时期简帛方书中所... 通过考释马王堆《五十二病方》《养生方》、阜阳《万物》、《武威汉代医简》及新近成都天回汉墓出土《治六十病和齐汤法》等简帛方书中出现的若干药物异名,并与《本草纲目》的“释名”相参证,认为近年来出土的战国秦汉时期简帛方书中所见的药名,往往是本草典籍所记载的“异名”。李时珍《本草纲目》“释名”中所引证的本草名物训诂资料,为考据这些药名提供了可资借鉴的书证。指出今后在出土医学文献研究中,应重视《本草纲目》的“释名”在出土文献药物考释中的价值,以促进出土医药文献名物考证的系统整理。 展开更多
关键词 李时珍 《本草纲目》释名 出土文献 药物考释
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数据要素市场化能否成为区域协调发展“新引擎”?——基于产业结构升级视角的实证检验
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作者 于孝建 吴浩伟 肖炜麟 《财经理论与实践》 北大核心 2026年第1期116-124,共9页
基于2011-2022年中国31个省(区、市)面板数据,构建四维区域协调发展指标体系与五维数据要素市场化水平评估框架,实证探究数据要素市场化是否能够成为推动区域协调发展的“新引擎”,结果表明:数据要素市场化有效推动区域协调发展,对经济... 基于2011-2022年中国31个省(区、市)面板数据,构建四维区域协调发展指标体系与五维数据要素市场化水平评估框架,实证探究数据要素市场化是否能够成为推动区域协调发展的“新引擎”,结果表明:数据要素市场化有效推动区域协调发展,对经济发展、公共服务、基础设施和人民生活等子系统均产生积极且显著的影响;数据要素市场化的优化配置推动了产业结构的升级,进而提升区域协调发展水平;数据要素市场化对西部和东北地区效应突出,对中部地区因产业嵌入不足而效应不显著。鉴于此,应加速完善数据要素制度体系,深化数据与产业融合,实施区域差异化策略,释放数据要素边际效益。 展开更多
关键词 区域协调发展 数据要素市场化 产业结构升级 数字经济 全国统一大市场
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石灰石-粉煤灰-水泥胶凝体系的水化动力学模型及强度预测
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作者 吴浪 田玉凤 +2 位作者 郭毅 何美美 雷斌 《功能材料》 北大核心 2026年第2期10-18,共9页
石灰石-粉煤灰-水泥(LF^(3))作为一种新型辅助胶凝材料,具备良好的环境适应性和力学性能。然而,当前对其水化机制与强度发展规律的理论研究仍不充分。为此,综合考虑了石灰石、粉煤灰掺料的水化反应和火山灰反应过程,建立了LF^(3)胶凝体... 石灰石-粉煤灰-水泥(LF^(3))作为一种新型辅助胶凝材料,具备良好的环境适应性和力学性能。然而,当前对其水化机制与强度发展规律的理论研究仍不充分。为此,综合考虑了石灰石、粉煤灰掺料的水化反应和火山灰反应过程,建立了LF^(3)胶凝体系的水化动力学模型。模型基于氢氧化钙和铝酸盐反应机制,将水化伴生物(水、氢氧化钙)作为动态输入变量,模拟三元体系水化过程演化。进一步结合Powers强度理论,建立了水化程度驱动下的强度预测模型,并通过文献数据进行参数拟合与准确性验证。结果显示,模型预测强度与实测值相关性良好(R^(2)=0.99,RMSE=1.48 MPa),表明模型具备较强的适用性与泛化能力。研究表明,石灰石有助于提升早期强度,粉煤灰通过火山灰反应增强后期性能,LF^(3)体系整体优于二元复合胶凝材料及普通硅酸盐水泥。不同龄期下最优配比呈现由高石灰石-低粉煤灰向高粉煤灰-低石灰石转变的趋势。为LF^(3)胶凝体系的水化机制揭示与配比优化提供了理论支持,为低碳高性能混凝土设计提供预测工具。 展开更多
关键词 石灰石-粉煤灰-水泥(LF^(3)) 水化动力学 胶凝体系 强度预测
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数字化水平何以赋能新质生产力发展——来自2009-2022年中国285个城市的经验证据
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作者 何立华 谢陆阳 《中南民族大学学报(人文社会科学版)》 北大核心 2026年第1期124-134,186,共12页
加快发展新质生产力是推动高质量发展的内在要求和重要着力点。以“由技术革命性突破、生产要素创新性配置、产业深度转型升级而催生”为线索,基于2009-2022年中国285个地级市的面板数据,使用双向固定效应模型和中介效应模型,探讨数字... 加快发展新质生产力是推动高质量发展的内在要求和重要着力点。以“由技术革命性突破、生产要素创新性配置、产业深度转型升级而催生”为线索,基于2009-2022年中国285个地级市的面板数据,使用双向固定效应模型和中介效应模型,探讨数字化水平对新质生产力发展的影响及作用机制。研究的主要发现有:(1)数字化水平可以促进新质生产力的发展,这一结论在稳健性检验之后仍然成立。(2)产业结构升级和区域创新能力,是数字化水平促进新质生产力发展的重要桥梁,且这一路径支持排他性检验。(3)数字化水平对新质生产力发展的影响具有异质性,东部与中西部存在较大差异。基于以上发现,提出了一系列政策措施和建议。 展开更多
关键词 新质生产力 数字化水平 区域创新能力 产业结构升级
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中国沿海地区专精特新“小巨人”企业创新的空间特征与类型划分
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作者 李博 张晨晨 《地理科学进展》 北大核心 2026年第1期62-76,共15页
研究专精特新“小巨人”企业的创新空间对推动地区因地制宜培育新质生产力具有重要作用。论文基于沿海地区2019—2023年专精特新“小巨人”企业的专利数据,从创新数量和创新质量两个维度对“小巨人”企业的创新水平进行测度,刻画其空间... 研究专精特新“小巨人”企业的创新空间对推动地区因地制宜培育新质生产力具有重要作用。论文基于沿海地区2019—2023年专精特新“小巨人”企业的专利数据,从创新数量和创新质量两个维度对“小巨人”企业的创新水平进行测度,刻画其空间和行业分布特征,并揭示不同城市“小巨人”企业创新发展的类型特点。研究表明:(1)“小巨人”企业的创新数量不断增长,其创新空间呈非均衡性特征,主要以长三角、珠三角和环渤海城市群为集聚核心。创新数量同时具有明显的行业集中性,主要以机械设备制造业、高新技术服务业和高新技术制造业为主。(2)“小巨人”企业创新质量不断上升,创新空间较为均衡;不同行业的创新质量呈上升态势,但存在较大差异。(3)沿海各城市“小巨人”企业的创新发展可分为低数量—低质量、低数量—高质量、高数量—低质量和高数量—高质量4个类别,各类型城市的主导产业也存在差异。研究认为,沿海地区“小巨人”企业的创新发展具有“数量集聚、质量均衡、行业分化”的特征,不同城市应结合自身类型,以“小巨人”企业为抓手,因地制宜发展新质生产力。 展开更多
关键词 专精特新“小巨人”企业 创新数量 创新质量 沿海地区
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磁性壳聚糖基吸附材料的制备及水处理应用进展
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作者 黄瑶瑶 李冉 +7 位作者 陈俊渲 邓金梅 祝彬淏 卢凤兰 冷祯颐 范围 李永强 郑怀礼 《化工进展》 北大核心 2026年第2期923-935,共13页
系统回顾了磁性壳聚糖基吸附材料的制备方法及其在水处理中的应用进展。首先,详细介绍了磁性壳聚糖的多种制备方法,包括交联法、共沉淀法、低共熔溶剂法、分子组装及动态共价键等,并探讨了不同方法对材料结构及性能的影响。其次,重点阐... 系统回顾了磁性壳聚糖基吸附材料的制备方法及其在水处理中的应用进展。首先,详细介绍了磁性壳聚糖的多种制备方法,包括交联法、共沉淀法、低共熔溶剂法、分子组装及动态共价键等,并探讨了不同方法对材料结构及性能的影响。其次,重点阐述了改性磁性壳聚糖基材料的制备策略,如物理改性、化学改性和生物修饰改性等,分析了改性对材料吸附性能的提升作用。在水处理应用方面,本文系统总结了改性磁性壳聚糖基材料对单一种类污染废水(如重金属离子、染料、抗生素及含油废水)的高效吸附分离性能,并进一步探讨了其在重金属-染料、重金属-抗生素等二元复合污染废水及多种复合污染废水中的协同处理效果。此外,还分析了材料在水处理领域的其他应用潜力。通过对比不同制备方法及改性策略的优缺点,研究结果表明磁性壳聚糖基吸附材料因其高吸附容量、易回收性及环境友好性,在水处理领域展现出显著优势。最后,对当前研究的局限性进行了总结,并展望了未来的研究方向,如绿色合成工艺的优化、多功能复合材料的开发及实际工程应用的拓展等,为磁性壳聚糖基吸附材料的进一步研究与应用提供了参考。 展开更多
关键词 吸附 吸附剂 有机化合物 改性制备 磁性壳聚糖基吸附材料 废水处理
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