检索结果-南通市图书馆

Effects of Boron Addition on the Microstructure and Mechanical Properties ofγ′‑Strengthened Directionally Solidified CoNi‑Base Superalloy

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Acta Metallurgica Sinica(English Letters) 2024年第8期37卷 1438-1452页

作者： shasha Qu Yingju Li Bingyu Lu Cuiping Wang Yuansheng Yang Institute of Metal Research Chinese Academy of SciencesShenyang 110016China Guangdong Institute of Special Equipment Inspection and Research Foshan 528251China College of Materials and Fujian Provincial key Laboratory of Materials Genome Xiamen UniversityXiamen 361005China

The effects of B addition on microstructure and mechanical properties of aγ′-strengthened CoNi-base superalloy are *** addition of B leads to a substantial increase in the volume fraction of both the eutectic structure and *** CoNi-base alloy shows a high solubility limit for the element *** become noticeable in the area surrounding the eutectic structure after the B level exceeds 0.46 at.%.It is found that the compression property and stress rupture life of the 4W2Ta alloys exhibit an initial rise followed by a subsequent drop as the B content gradually increases from 0.08 to 0.78 at.%.The 4W2Ta0.46B alloy demonstrates the most excellent high-temperature strength and stress rupture life,revealing that a moderate amount of B in the alloy noticeably enhances its mechanical properties by enhancing the grain boundary cohesion.

关键词： CoNi-base superalloy Borides Grain boundary Microstructure Mechanical properties

Predicting PM_(2.5) Concentration in the Yangtze River Delta Region Using Climate System Monitoring Indices and Machine Learning

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Meteorological Research 2024年第2期38卷 249-261页

作者： Jinghui MA Shiquan WAN shasha XU Chanjuan WANG Danni QIU Shanghai Typhoon Institute Shanghai Meteorological ServiceShanghai 200030 key Laboratory of Polar Atmosphere-Ocean-Iice System for Weather and Climate Ministry of EducationDepartment of Atmospheric and Oceanic SciencesFudan UniversityShanghai 200438 Shanghai key Laboratory of Meteorology and Health Shanghai Meteorological ServiceShanghai 200030 Yangzhou Meteorological Office Yangzhou 225001 Department of Physics Yangzhou UniversityYangzhou 225003

Changing meteorological conditions during autumn and winter have considerable impact on air quality in the Yangtze River Delta(YRD)*** climatic factors,such as sea surface temperature and sea ice,together with the atmospheric circulation,directly affect meteorological conditions in the YRD region,thereby modulating the variation in atmospheric PM_(2.5) *** study used the evolutionary modeling machine learning technique to investigate the lag relationship between 144 climate system monitoring indices and autumn/winter PM_(2.5) concentration over 0-12 months in the YRD *** calculating the contribution ratios and lagged correlation coefficients of all indices over the previous 12 months,the top 36 indices were selected for model ***,the nine indices that contributed most to the PM_(2.5) concentration in the YRD region,including the decadal oscillation index of the Atlantic Ocean and the consistent warm ocean temperature index of the entire tropical Indian Ocean,were selected for physical mechanism *** evolutionary model was developed to forecast the average PM_(2.5) concentration in major cities of the YRD in autumn and winter,with a correlation coefficient of *** model testing,the correlation coefficient between the predicted and observed PM_(2.5) concentrations was in the range of 0.73-0.83 and the root-mean-square error was in the range of 9.5-11.6μg m-3,indicating high predictive *** model performed exceptionally well in capturing abnormal changes in PM_(2.5) concentration in the YRD region up to 50 days in advance.

关键词： PM_(2.5)concentration machine learning evolutionary modeling seasonal prediction

SciCN:A Scientific Dataset for Chinese Named Entity Recognition

在线全文

学校读者我要写书评

暂无评论

Computers, Materials & Continua 2024年第3期78卷 4303-4315页

作者： Jing Yang Bin Ji shasha Li Jun Ma Jie Yu College of Computer National University of Defense TechnologyChangsha410073China

Named entity recognition(NER)is a fundamental task of information extraction(IE),and it has attracted considerable research attention in recent *** abundant annotated English NER datasets have significantly promoted the NER research in the English *** contrast,much fewer efforts are made to the Chinese NER research,especially in the scientific domain,due to the scarcity of Chinese NER *** alleviate this problem,we present aChinese scientificNER dataset–SciCN,which contains entity annotations of titles and abstracts derived from 3,500 scientific *** manually annotate a total of 62,059 entities,and these entities are classified into six *** to English scientific NER datasets,SciCN has a larger scale and is more diverse,for it not only contains more paper abstracts but these abstracts are derived from more research *** investigate the properties of SciCN and provide baselines for future research,we adapt a number of previous state-of-theart Chinese NER models to evaluate *** results show that SciCN is more challenging than other Chinese NER *** addition,previous studies have proven the effectiveness of using lexicons to enhance Chinese NER *** by this fact,we provide a scientific domain-specific *** results demonstrate that our lexicon delivers better performance gains than lexicons of other *** hope that the SciCN dataset and the lexicon will enable us to benchmark the NER task regarding the Chinese scientific domain and make progress for future *** dataset and lexicon are available at:https://***/yangjingla/***.

关键词： Named entity recognition dataset scientific information extraction lexicon

Curcumin delivery nanoparticles based on Maillard reaction of Haematococcus pluvialis protein/galactose for alleviating acute alcoholic liver damage

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Food Science and Human Wellness 2024年第5期13卷 2629-2641页

作者： Xinyi Liu Yukun Song shasha Cheng Mingqian Tan School of Food Science and Technology Dalian Polytechnic UniversityDalian 116034China National Engineering Research Center of Seafood Dalian 116034China

The aim of this study is to investigate the feasibility of Maillard reaction products of Haematococcus pluvialis protein and galactose(HPP-GAL)for improving the bioactivities of curcumin(CUR)for alleviating alcoholic liver *** was embedded into HPP-GAL nanoparticles by the self-assembly of hydrogen bonding and hydrophobic interaction with the particle size around 200 ***-GAL enhanced the encapsulation efficiency and loading amount of CUR with the value of(89.21±0.33)%and(0.500±0.004)%,*** stabilities of CUR under strong acid,salt ion stability and ultraviolet irradiation conditions were improved by the ***-GAL-CUR nanoparticles exhibited excellent concentration-dependent in vitro antioxidant activities including DPPH and ABTS scavenging rates,and better protective effect on CUR against gastric acid environment as well as longer release of CUR in simulated intestinal *** addition,the HPPGAL-CUR delivery system possessed liver targeting property due to the existence of GAL,which could effectively alleviate the alcohol-induced liver damage and the inflammation indexes by inhibiting the oxidative ***,HPP-GAL-CUR nanoparticles might be a potential candidate system for the prevention of alcoholic liver damage in the future.

关键词： Haematococcus pluvialis protein Galactose Curcumin nanocarrier Maillard reaction Alcoholic liver damage Liver targeting

Adaptively Enhancing Facial Expression Crucial Regions via a Local Non-local Joint Network

在线全文

学校读者我要写书评

暂无评论

Machine Intelligence Research 2024年第2期21卷 331-348页

作者： Guanghui Shi shasha Mao Shuiping Gou Dandan Yan Licheng Jiao Lin Xiong School of Artificial Intelligence Xidian UniversityXi'an 710000China Applied Research Laboratory Sense TimeXi'an 710000China

Facial expression recognition(FER)is still challenging due to the small interclass discrepancy in facial expression *** view of the significance of facial crucial regions for FER,many existing studies utilize the prior information from some annotated crucial points to improve the performance of ***,it is complicated and time-consuming to manually annotate facial crucial points,especially for vast wild expression *** on this,a local non-local joint network is proposed to adaptively enhance the facial crucial regions in feature learning of FER in this *** the proposed method,two parts are constructed based on facial local and non-local information,where an ensemble of multiple local networks is proposed to extract local features corresponding to multiple facial local regions and a non-local attention network is addressed to explore the significance of each local *** particular,the attention weights obtained by the non-local network are fed into the local part to achieve interactive feedback between the facial global and local ***,the non-local weights corresponding to local regions are gradually updated and higher weights are given to more crucial ***,U-Net is employed to extract the integrated features of deep semantic information and low hierarchical detail information of expression ***,experimental results illustrate that the proposed method achieves more competitive performance than several state-of-the-art methods on five benchmark datasets.

关键词： Facial expression recognition deep neural network multiple network ensemble attention network facial crucial regions

Span-based joint entity and relation extraction augmented with sequence tagging mechanism

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Science China(Information Sciences) 2024年第5期67卷 84-98页

作者： Bin JI shasha LI Hao XU Jie YU Jun MA Huijun LIU Jing YANG College of Computer National University of Defense Technology

Span-based joint extraction simultaneously conducts named entity recognition(NER) and relation extraction(RE) in a text span form. However, since previous span-based models rely on span-level classifications, they cannot benefit from token-level label information, which has been proven advantageous for the task. In this paper, we propose a sequence tagging augmented span-based network(STSN), a spanbased joint model that can make use of token-level label information. In STSN, we construct a core neural architecture by deep stacking multiple attention layers, each of which consists of three basic attention *** the one hand, the core architecture enables our model to learn token-level label information via the sequence tagging mechanism and then uses the information in the span-based joint extraction; on the other hand, it establishes a bi-directional information interaction between NER and RE. Experimental results on three benchmark datasets show that STSN consistently outperforms the strongest baselines in terms of F1,creating new state-of-the-art results.

关键词： joint extraction named entity recognition relation extraction span sequence tagging mechanism

Effect of burial depth of a new tunnel on the seismic response of an existing tunnel

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Earthquake Engineering and Engineering Vibration 2024年第4期23卷 863-882页

作者： Ma Runbo Cao Qikun Lu shasha Zhao Dongxu Zhang Yanan Xu Hong College of Civil Engineering Liaoning Technical UniversityFuxin 123000China key Laboratory of Urban Security and Disaster Engineering of Ministry of Education Beijing University of TechnologyBeijing 100124China

Burial depth is a crucial factor affecting the forces and deformation of tunnels during *** key issue is a lack of understanding of the effect of a change in the buried depth of a single-side tunnel on the seismic response of a double-tunnel *** this study,shaking table tests were designed and performed based on a tunnel under construction in Dalian,*** models were established using the equivalent linear method combined with ABAQUS finite element software to analyze the seismic response of the interacting *** results showed that the amplification coefficient of the soil acceleration did not change evidently with the burial depth of the new tunnel but decreased as the seismic amplitude *** addition,the existing tunnel acceleration,earth pressure,and internal force were hardly affected by the change in the burial depth;for the new tunnel,the acceleration and internal force decreased as the burial depth increased,while the earth pressure *** shows that the earth pressure distribution in a double-tunnel system is relatively complex and mainly concentrated on the arch spandrel and arch springing of the relative ***,when the horizontal clearance between the center of the two tunnels was more than twice the sum of the radius of the outer edges of the two tunnels,the change in the burial depth of the new tunnel had little effect on the existing one,and the tunnel structure was deemed *** results provide a preliminary understanding and reference for the seismic performance of a double-tunnel system.

关键词： burial depth new tunnel existing tunnel seismic response shaking table tests numerical simulations

Control of light-matter interactions in two-dimensional materials with nanoparticle-on-mirror structures

在线全文

学校读者我要写书评

暂无评论

Opto-Electronic Science 2024年第7期3卷 1-19页

作者： shasha Li Yini Fang Jianfang Wang School of Integrated Circuits Sun Yat-sen UniversityShenzhen 518107China Department of Physics The Chinese University of Hong KongShatinHong Kong SAR 999077China

Light–matter interactions in two-dimensional(2D)materials have been the focus of research since the discovery of *** light–matter interaction length in 2D materials is,however,much shorter than that in bulk materials owing to the atomic nature of 2D *** nanostructures are usually integrated with 2D materials to enhance the light–matter interactions,offering great opportunities for both fundamental research and technological ***-on-mirror(NPo M)structures with extremely confined optical fields are highly desired in this *** addition,2D materials provide a good platform for the study of plasmonic fields with subnanometer resolution and quantum plasmonics down to the characteristic length scale of a single atom.A focused and up-to-date review article is highly desired for a timely summary of the progress in this rapidly growing field and to encourage more research efforts in this *** this review,we will first introduce the basic concepts of plasmonic modes in NPo M *** between plasmons and quasi-particles in 2D materials,e.g.,excitons and phonons,from weak to strong coupling and potential applications will then be described in *** phenomena in subnanometer metallic gaps separated by 2D materials,such as quantum tunneling,will also be *** will finally discuss phenomena and physical processes that have not been understood clearly and provide an outlook for future *** believe that the hybrid systems of2D materials and NPo M structures will be a promising research field in the future.

关键词： light-matter interactions nanoparticle-on-mirror structures plasmonic enhancement two-dimensional materials

Unsaturated bi-heterometal clusters in metal-vacancy sites of 2D MoS2 for efficient hydrogen evolution

在线全文

学校读者我要写书评

暂无评论

Carbon Energy 2024年第3期6卷 264-275页

作者： Gonglei Shao Jie Xu shasha Gao Zhang Zhang Song Liu Xu Zhang Zhen Zhou Interdisciplinary Research Center for Sustainable Energy Science and Engineering(IRC4SE2) School of Chemical EngineeringZhengzhou UniversityZhengzhouHenanChina College of Chemistry and Materials Engineering Wenzhou UniversityWenzhouZhejiangChina key Laboratory of Advanced Energy Materials Chemistry(Ministry of Education) College of ChemistryNankai UniversityTianjinChina State key Laboratory of Chemo/Biosensing and Chemometrics Institute of Chemical Biology and Nanomedicine(ICBN)College of Chemistry and Chemical EngineeringHunan UniversityChangshaHunanChina Institute of New Energy Material Chemistry School of Materials Science and EngineeringNankai UniversityTianjinChina

The valence states and coordination structures of doped heterometal atoms in two-dimensional(2D)nanomaterials lack predictable regulation ***,a robust method is proposed to form unsaturated heteroatom clusters via the metal-vacancy restraint mechanism,which can precisely regulate the bonding and valence state of heterometal atoms doped in 2D molybdenum *** unsaturated valence state of heterometal Pt and Ru cluster atoms form a spatial coordination structure with Pt–S and Ru–O–S as catalytically active *** them,the strong binding energy of negatively charged suspended S and O sites for H+,as well as the weak adsorption of positively charged unsaturated heterometal atoms for H*,reduces the energy barrier of the hydrogen evolution reaction proved by theoretical ***,the electrocatalytic hydrogen evolution performance is markedly improved by the ensemble effect of unsaturated heterometal atoms and highlighted with an overpotential of 84 mV and Tafel slope of 68.5 mV dec^(−1).In brief,this metal vacancy-induced valence state regulation of heterometal can manipulate the coordination structure and catalytic activity of heterometal atoms doped in the 2D atomic lattice but not limited to 2D nanomaterials.

关键词： clusters hydrogen evolution reaction metal vacancy MoS2 unsaturated heterometal