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Solvent switching and purification of colloidal nano- particles through water/oil Interfaces within a density gradient

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Nano Research 2014年第11期7卷 1670-1679页

作者： Yun Kuang Sha Song Xiaofei liu Minglin li zhao cai liang Luo Xiaoming Sun State Key Laboratory of Chemical Resource Engineering Beijing University of Chemical Technology Beijing 100029 China

Traditional post-treatment of colloidal nanoparticles （NPs） usually involves repeated centrifugation-wash-sonication processes to separate NPs from the original synthetic environment; however, such separation processes have either high energy cost or low efficiency and tend to cause aggregation. Here we show a general and scalable colloid post-processing technique based on density gradient centrifugation through water/oil interfaces. Such a one-step technique can switch the solvent in a colloid at almost any concentration without aggregation, and meanwhile purify colloidal nanoparticles by separating them from by-products and environmental impurities. Droplet sedimentation was shown to be the mechanism of this one-step concentration/purification process, and mathematical modeling was established to quantify the accumulation and sedimentation velocities of different NPs.

关键词： density gradient water/oil interface solvent switching purification

Photocatalytic Activities of Amorphous TiO_2-Cr Thin Films Prepared by Magnetron Sputtering

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Journal of Wuhan University of Technology(Materials Science) 2008年第5期23卷 610-616页

作者：黄佳木 College of Materials Science and Engineering Chongqing University

Chrome-doped titanium oxide films were prepared by reactive magnetron sputtering method. The films deposited on glass slides at room temperature were investigated by atom force microscope, X-ray diffractometer, X-ray photoelectron spectroscopy, UV-Vis spectrophotometer, the photoluminescence （PL） and ellipse polarization apparatus. The results indicate that TiO2-Cr film exists in the form of amorphous. The prepared films possess a band gap of less than 3.20 eV, and a new absorption peak. The films, irradiated for 5 h under UV light, exhibit excellent photocatalytic activities with the optimum decomposition rate at 98.5% for methylene blue. Consequently, the thickness threshold on these films is 114 nm, at which the rate of photodegradation is 95% in 5 h. When the thickness is over 114 nm, the rate of photodegradation becomes stable. This result is completely different from that of crystalloid TiO2 thin film.

关键词： amorphous TiO2 magnetron sputtering TiO2-Cr thin films photocatalysis threshold

Storage time affects the level and diagnostic efficacy of plasma biomarkers for neurodegenerative diseases

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Neural Regeneration Research 2025年第8期20卷 2373-2381页

作者： lifang zhao Mingkai Zhang Qimeng li Xuemin Wang Jie Lu Ying Han Yanning cai Department of Clinical Biobank Xuanwu HospitalCapital Medical UniversityBeijingChina Beijing Geriatric Medical Research Center BeijingChina Department of Neurology Xuanwu HospitalCapital Medical UniversityBeijingChina Department of Radiology and Nuclear Medicine Xuanwu HospitalCapital Medical UniversityBeijingChina Beijing Key Laboratory of Magnetic Resonance Imaging and Brain Informatics BeijingChina Key Laboratory of Neurodegenerative diseases Ministry of EducationBeijingChina School of Biomedical Engineering Hainan UniversityHaikouHainan ProvinceChina Center of Alzheimer’s Disease Beijing Institute for Brain DisordersBeijingChina National Clinical Research Center for Geriatric Diseases BeijingChina Institute of Biomedical Engineering Shenzhen Bay LaboratoryGaoke Innovation CenterShenzhenGuangdong ProvinceChina Department of Neurobiology Xuanwu HospitalCapital Medical UniversityBeijingChina

Several promising plasma biomarker proteins,such as amyloid-β(Aβ),tau,neurofilament light chain,and glial fibrillary acidic protein,are widely used for the diagnosis of neurodegenerative ***,little is known about the long-term stability of these biomarker proteins in plasma samples stored at-80°*** aimed to explore how storage time would affect the diagnostic accuracy of these biomarkers using a large *** samples from 229 cognitively unimpaired individuals,encompassing healthy controls and those experiencing subjective cognitive decline,as well as 99 patients with cognitive impairment,comprising those with mild cognitive impairment and dementia,were acquired from the Sino Longitudinal Study on Cognitive Decline *** samples were stored at-80°C for up to 6 years before being used in this *** results showed that plasma levels of Aβ42,Aβ40,neurofilament light chain,and glial fibrillary acidic protein were not significantly correlated with sample storage ***,the level of total tau showed a negative correlation with sample storage ***,in individuals without cognitive impairment,plasma levels of total protein and tau phosphorylated protein threonine 181(p-tau181)also showed a negative correlation with sample storage *** was not observed in individuals with cognitive ***,we speculate that the diagnostic accuracy of plasma p-tau181 and the p-tau181 to total tau ratio may be influenced by sample storage ***,caution is advised when using these plasma biomarkers for the identification of neurodegenerative diseases,such as Alzheimer's ***,in cohort studies,it is important to consider the impact of storage time on the overall results.

关键词： Alzheimer’s disease amyloid-β diagnostic ability glial fibrillary acidic protein neurodegeneration neurofilament light chain plasma biomarkers single molecule array storage time tau

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费氏易史献考实

周易研究 2016年第5期 48-56页

作者：李才朝山东大学儒学高等研究院山东济南250100

费直解《易》的方法与思路谨遵孔学之旧,或为孔学正宗,但也走向了僵化不前。郑玄、王弼等"传其学"实际上是效慕其朴实的解经作风,汲取其"以《彖》《象》《系辞》十篇文言解说上下经"的思路。而费氏本为古文,绝无可疑。刘向校《易》、班... 详细信息

费直解《易》的方法与思路谨遵孔学之旧,或为孔学正宗,但也走向了僵化不前。郑玄、王弼等"传其学"实际上是效慕其朴实的解经作风,汲取其"以《彖》《象》《系辞》十篇文言解说上下经"的思路。而费氏本为古文,绝无可疑。刘向校《易》、班固录《易》,皆指示西汉传《易》的主流,其文本是同源的;而"本以古字,号古文易"是专就费直传学而言,并不以王璜传学为中心意,后世学者对古文易之疑多系误读史献而起。

关键词：费直易学古文今文

A Cross Attention Transformer-Mixed Feedback Video Recommendation Algorithm Based on DIEN

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Computers, Materials & Continua 2025年第1期82卷 977-996页

作者： Jianwei Zhang Zhishang zhao Zengyu cai Yuan Feng liang Zhu Yahui Sun College of Software Engineering Zhengzhou University of Light IndustryZhengzhou450000China Faculty of Information Engineering Xuchang Vocational Technical CollegeXuchang461000China College of Computer Science and Technology Zhengzhou University of Light IndustryZhengzhou450000China College of Electronics and Information Zhengzhou University of Light IndustryZhengzhou450000China

The rapid development of short video platforms poses new challenges for traditional recommendation *** systems typically depend on two types of user behavior feedback to construct user interest profiles:explicit feedback(interactive behavior),which significantly influences users’short-term interests,and implicit feedback(viewing time),which substantially affects their long-term ***,the previous model fails to distinguish between these two feedback methods,leading it to predict only the overall preferences of users based on extensive historical behavior ***,it cannot differentiate between users’long-term and shortterm interests,resulting in low accuracy in describing users’interest states and predicting the evolution of their *** paper introduces a video recommendationmodel calledCAT-MFRec(CrossAttention Transformer-Mixed Feedback Recommendation)designed to differentiate between explicit and implicit user feedback within the DIEN(Deep Interest Evolution Network)*** study emphasizes the separate learning of the two types of behavioral feedback,effectively integrating them through the cross-attention ***,it leverages the long sequence dependence capabilities of Transformer technology to accurately construct user interest profiles and predict the evolution of user *** results indicate that CAT-MF Rec significantly outperforms existing recommendation methods across various performance *** advancement offers new theoretical and practical insights for the development of video recommendations,particularly in addressing complex and dynamic user behavior patterns.

关键词： Video recommendation user interest cross-attention transformer

Moment Redistribution Effect of the Continuous Glass Fiber Reinforced Polymer-Concrete Composite Slabs Based on Static Loading Experiment

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Structural Durability & Health Monitoring 2025年第1期19卷 105-123页

作者： zhao-Jun Zhang Wen-Wei Wang Jing-Shui Zhen Bo-Cheng li De-Cheng cai Yang-Yang Du Hui Huang Offshore Oil Engineering Co.Ltd. Tianjin300461China Department of Bridge Engineering School of TransportationSoutheast UniversityNanjing211189China

This study aimed to investigate the moment redistribution in continuous glass fiber reinforced polymer(GFRP)-concrete composite slabs caused by concrete cracking and steel bar yielding in the negative bending moment *** experimental bending moment redistribution test was conducted on continuous GFRP-concrete composite slabs,and a calculation method based on the conjugate beam method was *** composite slabs were formed by combining GFRP profiles with a concrete layer and supported on steel beams to create two-span continuous composite slab *** methods,epoxy resin bonding,and stud connection,were used to connect the composite slabs with the steel *** experimental findings showed that the specimen connected with epoxy resin exhibited two moments redistribution phenomena during the loading process:concrete cracking and steel bar yielding at the internal *** contrast,the composite slab connected with steel beams by studs exhibited only one-moment redistribution phenomenon throughout the loading *** the concrete at the internal support cracked,the bending moment decreased in the internal support section and increased in the midspan *** the steel bars yielded,the bending moment further decreased in the internal support section and increased in the mid-span *** GFRP profiles do not experience cracking,there was no significant decrease in the bending moment of the mid-span *** test specimens experienced compressive failure of concrete at the mid-span *** results showed good agreement between the calculated and experimental values of bending moments in the mid-span section and internal support *** proposed model can effectively predict the moment redistribution behavior of continuous GFRP-concrete composite slabs.

关键词： Moment redistribution GFRP-concrete composite slabs bending moment experimental study analysis model

Decision making module based on stochastic magnetic tunnel junctions

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Science China(Physics,Mechanics & Astronomy) 2025年第1期Mechanics & Astronomy) .卷 202-209页

作者： Yifan Miao li zhao Yajun Zhang Zhe Yuan Center for Advanced Quantum Studies and Department of Physics Beijing Normal University Institute for Nanoelectric Devices and Quantum Computing Fudan University Interdisciplinary Center for Theoretical Physics and Information Sciences Fudan University

In biological neural systems, noise is ubiquitous but does not affect the correct decisions made in the complex cognitive ***-making in biological neural system is typically achieved by accumulating input information over a period of *** by recent developments in neurosciences, we design a decision-making module based on spintronic devices, utilizing superparamagnetic tunnel junctions as artificial neurons. The feasibility of this decision-making module is verified through circuit simulations. Taking a multi-layer perceptron as an example, the module significantly improves the accuracy of the perceptron in the handwritten digit recognition task. Furthermore, the spintronic decision-making module offers advantages over the conventional pooling methods, such as adaptive decision time, high performance and the absence of analog-to-digital conversion. The decision-making module is flexible to be integrated into artificial neural networks and provides a general yet effective solution to enhance performance against device noise.

关键词： neuromorphic computing spintronics magnetic tunnel junction neural networks

Gradient maturation experiment on hairs implies taphonomic changes in fossil hairs

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Science China Earth Sciences 2025年第1期68卷 62-73页

作者： Xin li Yibo ZHOU Tao zhao Xingjian HE Yanhong PAN State Key Laboratory for Mineral Deposits Research Center for Critical Earth Material Cycling Centre for Research and Education on Biological Evolution and Environment and Frontiers Science School of Earth Sciences and Engineering Nanjing University Institute of Palaeontology Yunnan Key Laboratory of Earth System Science Yunnan Key Laboratory for PalaeobiologyYunnan University

Mammalian hair, as a key feature related to endothermy, physical protection, and camouflage, has a long geohistorical record that dates back even to the Mesozoic. However, the limited information on the taphonomy of hair hinders the understanding of its evolutionary significance in deep time. To address this, we conducted taphonomic experiments to simulate the transformation process of black hair. The changes in the morphological structure, microscopic characteristics, and chemical composition of hair during the simulated fossilization process were documented by scanning electron microscopy, Fourier transform infrared(FTIR) spectroscopy, and Raman spectroscopy. Our results revealed that damage to the morphology of hair began at a mild temperature(150–175°C), and hair transformed into a fluid-like mass at a relatively high temperature(200°C). In addition, the morphological structure of melanosomes had relatively greater preservation potential than keratins did, and the microscopic features of melanosomes were persistently stable. The Raman and FTIR spectra indicated that the characteristic melanin and keratin peaks changed as the temperature increased. Although the chemical signals were not lost completely, the variations in the characteristic amide bands in the FTIR spectra indicate that the keratins severely degraded at high temperatures(>200°C), whereas the characteristic melanin bands in the Raman spectra suggested that melanin signals were still recognizable, even at high temperatures(>200°C). These results were confirmed by principal component analysis(PCA) and principal component analysis linear discriminant analysis(PCA–LDA). In addition, the Raman signals of all the samples in the simulated experiments were distinguished from the signals of common geological carbonaceous materials(humic acid), which suggested that Raman spectroscopy can be used to detect melanin in fossils.

关键词： Mammalian hair Melanin Keratin Fossilization Experimental taphonomy

IDSSCNN-XgBoost:Improved Dual-Stream Shallow Convolutional Neural Network Based on Extreme Gradient Boosting Algorithm for Micro Expression Recognition

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Computers, Materials & Continua 2025年第1期82卷 729-749页

作者： Adnan Ahmad zhao li Irfan Tariq Zhengran He School of Information Science and Engineering Southeast UniversityNanjing210016China

Micro-expressions(ME)recognition is a complex task that requires advanced techniques to extract informative features fromfacial *** deep neural networks(DNNs)with convolutional structures have been ***,unlike DNNs,shallow convolutional neural networks often outperform deeper models in mitigating overfitting,particularly with small ***,many of these methods rely on a single feature for recognition,resulting in an insufficient ability to extract highly effective *** address this limitation,in this paper,an Improved Dual-stream Shallow Convolutional Neural Network based on an Extreme Gradient Boosting Algorithm(IDSSCNN-XgBoost)is introduced for ME *** proposed method utilizes a dual-stream architecture where motion vectors(temporal features)are extracted using Optical Flow TV-L1 and amplify subtle changes(spatial features)via EulerianVideoMagnification(EVM).These features are processed by IDSSCNN,with an attention mechanism applied to refine the extracted effective *** outputs are then fused,concatenated,and classified using the XgBoost *** comprehensive approach significantly improves recognition accuracy by leveraging the strengths of both temporal and spatial information,supported by the robust classification power of *** proposed method is evaluated on three publicly available ME databases named Chinese Academy of Sciences Micro-expression Database(CASMEII),Spontaneous Micro-Expression Database(SMICHS),and Spontaneous Actions and Micro-Movements(SAMM).Experimental results indicate that the proposed model can achieve outstanding results compared to recent *** accuracy results are 79.01%,69.22%,and 68.99%on CASMEII,SMIC-HS,and SAMM,and the F1-score are 75.47%,68.91%,and 63.84%,*** proposed method has the advantage of operational efficiency and less computational time.

关键词： ME recognition dual stream shallow convolutional neural network euler video magnification TV-L1 XgBoost