检索结果-南通市图书馆

Acta Metallurgica Sinica(English Letters) 2024年第8期37卷 1411-1420页

作者： J.X.Cai B.M.Shi n.Li Y.Liu z.G.zhang Y.n.zan Q.z.Wang B.L.Xiao z.Y.Ma Shi‑Changxu Innovation Center for Advanced Materials Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China Key Laboratory of nuclear Materials and Safety Assessment Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China nuclear Equipment Division Beijing Institute of Nuclear EngineeringChina Nuclear Power Engineering Co.Ltd.Beijing 100840China Department of Materials Science School of Mechanical EngineeringShenyang UniversityShenyang 110044China

B_(4)C/Al composites are widely utilized as neutron absorbing materials for the storage and transportation of spent nuclear *** order to improve the high-temperature mechanical properties of B_(4)C/Al composites,in-situ nano-Al_(2)O_(3)was introduced utilizing oxide on Al powder *** this study,the Al_(2)O_(3)content was adjusted by utilizing spheroid Al powder with varying diameters,thereby investigating the impact of Al_(2)O_(3)content on the tensile properties of(B_(4)C+Al_(2)O_(3))/Al *** was found that the pinning effect of Al_(2)O_(3)on the grain boundaries could hinder the recovery of dislocations and lead to dislocation accumulation at high *** the result,with the increase in Al_(2)O_(3)content and the decrease in grain size,the high-temperature strength of the composites increased *** finest Al powder used in this investigation had a diameter of 1.4μm,whereas the resultant composite exhibited a maximum strength of 251 MPa at room temperature and 133 MPa at 350℃,surpassing that of traditional B_(4)C/Al composites.

关键词： Al matrix composites neutron absorbing materials (B_(4)C+Al_(2)O_(3))/Al composites High-temperature strength

Distinct Electrical and Mechanical Responses of a Cu-10Fe Composite Prepared by Hot-Pressed Sintering and Post Treatment

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2期37卷 255-265页

作者： X.Y.Yue S.Y.Peng X.zhang C.n.He Y.z.Tian Key Laboratory for Anisotropy and Texture of Materials(Ministry of Education) School of Materials Science and EngineeringNortheastern UniversityShenyang110819China School of Materials Science and Engineering and Tianjin Key Laboratory of Composite and Functional Materials Tianjin UniversityTianjin300350China Research Centre for Metallic Wires Northeastern UniversityShenyang110819China

A Cu-10wt%Fe composite was prepared through hot-pressed sintering,and the material was subsequently solution *** hot-pressed sintered and solution treated materials were rolled and *** precipitation behavior and performance changes were systematically studied by using scanning electron microscopy and transmission electron *** contrast to the hot-pressed sintered specimen,the solution treatment significantly affects the thermal stability and properties of the Cu-10wt%Fe *** Cu-10wt%Fe composite was prepared after solid solution,cold rolling and aging at 773 K for 1 h,and it obtained excellent tensile strength of 494 MPa,uniform elongation of 16.3%,electrical conductivity of 51.1%IACS and softening temperature of 838 *** for the distinct difference in thermal stability and properties between hot-pressed sintered and solution treated specimens were *** findings provide a theoretical basis for designing high-performance Cu-based in-situ composites by post treatment.

关键词： Cu-Fe composite Hot-pressed sintering Thermal stability Strength Electrical conductivity

PUnet: A Semi-Supervised Anomaly Detection Model for network Anomaly Detection Based on Positive Unlabeled Data

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Computers, Materials and Continua 2024年第1期81卷 327-343页

作者： Long G. zhang z. Faculty of Computing Harbin Institute of Technology Harbin 150000 China

network anomaly detection plays a vital role in safeguarding network security. However, the existing network anomaly detection task is typically based on the one-class zero-positive scenario. This approach is susceptible to overfitting during the training process due to discrepancies in data distribution between the training set and the test set. This phenomenon is known as prediction drift. Additionally, the rarity of anomaly data, often masked by normal data, further complicates network anomaly detection. To address these challenges, we propose the PUnet network, which ingeniously combines the strengths of traditional machine learning and deep learning techniques for anomaly detection. Specifically, PUnet employs a reconstruction-based autoencoder to pre-train normal data, enabling the network to capture potential features and correlations within the data. Subsequently, PUnet integrates a sampling algorithm to construct a pseudo-label candidate set among the outliers based on the reconstruction loss of the samples. This approach effectively mitigates the prediction drift problem by incorporating abnormal samples. Furthermore, PUnet utilizes the CatBoost classifier for anomaly detection to tackle potential data imbalance issues within the candidate set. Extensive experimental evaluations demonstrate that PUnet effectively resolves the prediction drift and data imbalance problems, significantly outperforming competing methods. © 2024 The Authors. Published by Tech Science Press.

关键词： candidate set CatBoost network anomaly detection representation learning

Precipitation of multi-type nano-quasicrystals in a Mg-zn-Y alloy

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 Magnesium and Alloys 2024年第3期12卷 997-1008页

作者： W.z.Wang X.z.zhou L.F.zhang H.Q.Ye z.Q.Yang Shenyang national Laboratory for Materials Science Institute of Metal ResearchChinese Academy of ScienceShenyang 110016China Ji Hua Laboratory Foshan 528251China Foshan University Foshan 528231China

Mg-6zn-1Y(at.%)ribbons with strengthening precipitates of multi-type nanoquasicrystals were prepared by melt-spinning followed by aging *** evolution of the rapidly solidified ribbons during isothermal aging was comprehensively studied using various electron microscopy *** new kinds of decagonal quasicrystals were formed in aged ribbons,in addition to precipitation of nanometer icosahedral ***-resolution observations reveal that both decagonal quasicrystals can be modeled by quasiperiodic tiling with decagonal clusters of 2.5 nm in diameter,but overlap of neighboring clusters in both decagonal quasicrystals is different from the Gummelt model observed in other quasicrystals.A shell composed of complex Laves Mg-zn domains was formed surrounding each decagonal quasicrystal precipitate upon prolonged *** addition,all kinds of nanoprecipitates exhibit excellent structure and size stability at 573 *** findings may have implications for not only fundamental studies about quasicrystals,but also microstructural manipulation of high-performance Mg alloys.

关键词： Quasicrystal Mg alloys Rapid solidification Scanning-transmission electron microscopy.

The new era of cardiovascular research:revolution.zing cardiovascular research with 3D models in a dish

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Medical Review 2024年第1期4卷 68-85页

作者： Yuan Yang Hao Yang Fedir n.Kiskin Joe z.zhang Institute of neurological and Psychiatric Disorders Shenzhen Bay LaboratoryShenzhenGuangdong ProvinceChina Institute of neurological and Psychiatric Disorders Shenzhen Bay LaboratoryShenzhen 518132Guangdong ProvinceChina

Cardiovascular research has heavily relied on studies using patient samples and animal ***,patient studies often miss the data from the crucial early stage of cardiovascular diseases,as obtaining primary tissues at this stage is *** animal models can offer some insights into disease mechanisms,although they usually do not fully recapitulate the phenotype of cardiovascular diseases and their *** recent years,a promising breakthrough has emerged in the form of in vitro three-dimensional(3D)cardiovascular models utilizing human pluripotent stem *** innovative models recreate the intricate 3D structure of the human heart and vessels within a controlled *** advancement is pivotal as it addresses the existing gaps in cardiovascular research,allowing scientists to study different stages of cardiovascular diseases and specific drug responses using human-origin *** this review,we first outline various approaches employed to generate these *** then comprehensively discuss their applications in studying cardiovascular diseases by providing insights into molecular and cellular changes associated with cardiovascular condi***,we highlight the potential of these 3D models serving as a platform for drug testing to assess drug efficacy and *** their immense potential,challenges persist,particularly in maintaining the complex structure of 3D heart and vessel models and ensuring their function is comparable to real ***,overcoming these challenges could revolution.ze cardiovascular *** has the potential to offer comprehensive mechanistic insights into human-specific disease processes,ultimately expediting the development of personalized therapies.

关键词： pluripotent stem cells three-dimensional(3D)models cardiac microtissues cardiac organoids vessel organoids organ-on-a-chip

Rational design of AgGaS/znS/znS quantum dots with a near-unity photoluminescence quantum yield via double shelling scheme

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 Materials Science & Technology 2024年第2期169卷 235-242页

作者： H.X.Lu H.Liu z.z.Fu Y.Y.Chen H.Q.Dai z.Hu W.L.zhang R.Q.Guo Institute for Electric Light Sources School of Information Science and TechnologyFudan UniversityShanghai 200433China Institute of Future Lighting Academy for Engineering and TechnologyFudan UniversityShanghai 200433China Yiwu Research Institute of Fudan University YiwuZhejiang 322000China zhongshan-Fudan Joint Innovation Center Zhongshan 528437China

In this study,a two-step method was used to synthesize highly luminescent AgGaS/znS/znS quantum dots(QDs).In the first step,an inner znS shell was formed via a one-pot method,which resulted in a smaller lattice mismatch between the AgGaS core and the outer znS shell,thereby facilitating the formation of a thick outer *** the two-step shelling process,the synthesized AgGaS/znS/znS QDs showed an excellent photoluminescence quantum yield(PLQY)of 96.4%with a peak wavelength of 508 nm,repre-senting the highest PLQY reported thus far for AgGaS ***,the effect of halogen ions in.zn precursors on the shelling process was *** was proposed that the capacity of halogen ions to coordinate with the QDs influenced the balance between.zn cation diffusion and znS shelling ***,the znS shelling reaction was dominant when.znCl_(2)was employed,while zn cation diffusion was the dominant process under the I^(−)-rich *** work provides insights into the interfacial restructuring during the znS shelling and offers a clear map for the tailored synthesis of core/shell QDs.

关键词： AgGaS Quantum dots Photoluminescence Core/shell Alloyed core/shell interface

In situ digital testing method for quality assessment of soft soil improvement with polyurethane

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 Rock Mechanics and Geotechnical Engineering 2024年第5期16卷 1732-1748页

作者： X.F.Wang C.J.Wang W.V.Yue z.J.zhang z.Q.Yue Department of Civil Engineering China University of Geosciences (Beijing)BeijingChina Department of Water Science and Engineering Zhengzhou UniversityZhengzhouChina Department of Geotechnical Engineering Tongji UniversityShanghaiChina Department of Civil Engineering The University of Hong KongChina

This study purposes an in situ testing method on quality assessment of soil *** drilling data includes the spatial distribution and in situ strength of untreated and treated soil along three different drillholes measured by on-site drilling monitoring *** factual drilling data can characterize the degree of soil improvement by penetration injection with permeable *** from on-site drilling monitoring shows that the linear zones represent constant drilling speeds shown in the plot of drill bit advancement *** drilling time,which indicates the spatial distributions of soil *** soil profile at the study site is composed of four layers,which includes fill,untreated silty clay,treated silty clay,and mucky *** results of soil profile are verified by the parallel site *** constant drilling speeds profile the coring-resistant strength of drilled *** comparing with the untreated silty clay,the constant drilling speeds of the treated silty clay have been decreased by 13.0-62.8%.Two drilling-speed-based indices of 61.2%and 65.6%are proposed to assess the decreased average drilling speed and the increased in situ strength of treated silty *** tests,*** compressive strength(UCS)test,have been performed with core sample to investigate and characterize in situ strength by comparing that with drilling *** show that the average predicted strengths of treated silty clay are 2.4-6.9 times higher than the average measured strength of untreated silty *** UCS-based indices of 374.5%and 344.2%verified the quality assessment(QA)results by this new in situ *** method provides a cost-effective tool for quality assessment of soil improvement by utilizing the digital drilling data.

关键词： Drilling process monitoring system Hydraulic rotary drilling process Constant drilling speed Soil improvement Quality assessment

Symmetry quantification and segmentation in STEM imaging through zernike moments

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Chinese Physics B 2024年第8期33卷 39-48页

作者： Jiadong Dan Cheng zhang 赵晓续 n.Duane Loh Department of Biological Sciences National University of SingaporeSingapore Center for Bioimaging Sciences(CBIS) National University of SingaporeSingapore Department of Physics National University of SingaporeSingapore School of Materials Science and Engineering Peking UniversityBeijing 100871China

We present a method using zernike moments for quantifying rotational and reflectional symmetries in scanning transmission electron microscopy(STEM)images,aimed at improving structural analysis of materials at the atomic *** technique is effective against common imaging noises and is potentially suited for low-dose imaging and identifying quantum *** showcase its utility in the unsupervised segmentation of polytypes in a twisted bilayer TaS_(2),enabling accurate differentiation of structural phases and monitoring transitions caused by electron beam *** approach enhances the analysis of structural variations in crystalline materials,marking a notable advancement in the characterization of structures in materials science.

关键词： scanning transmission electron microscopy(STEM) symmetry segmentation

Research on Fine-Grained RecognitionMethod for Sensitive Information in Social networks Based on CLIP

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Computers, Materials and Continua 2024年第1期81卷 1565-1580页

作者： zhang M. Shan F. Liu M. Wang z. School of Computer Science Zhongyuan University of Technology Zhengzhou 450007 China Henan Key Laboratory of Cyberspace Situation Awareness Zhengzhou 450001 China

With the emergence and development of social networks, people can stay in touch with friends, family, and colleaguesmore quickly and conveniently, regardless of their location. This ubiquitous digital internet environment has also ledtolarge-scaledisclosureof personal *** tothe complexity andsubtletyof sensitive information, traditional sensitive information identification technologies cannot thoroughly address the characteristics of each piece of data, thus weakening the deep connections between text and images. In this context, this paper adopts the CLIP model as a modality discriminator. By using comparative learning between sensitive image descriptions and images, the similarity between the images and the sensitive descriptions is obtained to determine whether the images contain sensitive information. This provides the basis for identifying sensitive information using different modalities. Specifically, if the original data does not contain sensitive information, only single-modality text-sensitive information identification is performed; if the original data contains sensitive information, multimodality sensitive information identification is conducted. This approach allows for differentiated processing of each piece of data, thereby achieving more accurate sensitive information identification. The aforementioned modality discriminator can address the limitations of existing sensitive information identification technologies, making the identification of sensitive information from the original data more appropriate and precise. © 2024 The Authors. Published by Tech Science Press.

关键词： Deep learning multi-modal fusion sensitive information recognition social networks