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Structural and Optical Properties and Emerging Applications of Metal Nanomaterials

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Journal of Materials Science & Technology 2008年第4期24卷 433-446页

作者： Tammg y.Olson Department of Chemistry and Biochemistry University of CaliforniaSanta CruzCA 95064USA

Nanomaterials possess intriguing optical properties that depend sensitively on size, shape, and material content of the structures. Controlling such structural characteristics of the nanostructures allows the tailoring of their physical and chemical properties, e.g. optical, electronic, and catalytic, to achieve what is desired lot specific applications of interest. This review will cover the development of various shapes for silver and gold nanomaterials with emphasis on their relation to optical properties. Examples of various modern synthetic methods and characterization techniques are highlighted. The influence of the metal nanomaterial＇s shape and optical absorption on surface enhanced Raman scattering （SERS） and a final note on new emerging applications of metal nanostructures are also discussed.

关键词： Nanomaterial Metal nanostructure Optical properties Size and shape effect

Influence on Microstructure of Micronized Sand as Cement Replacement in Cementitious Materials

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武汉理工大学学报 2010年第17期32卷 152-157页

作者： WANG y yE G Faculty of Civil Engineering and Geosciences Delft University of Technology2006 GA Delft 2600the Netherlands Magnel Lab for Concrete Research Ghent UniversityGhent 9050Belgium

In this study,micronized sand is selected as a kind of filler to partially replace cement in cementitious materials. This filler is considered as chemically inert material,which can not react with water or hydration products,but still indirectly influences the hydration in a positive way. In the experimental program,non-evaporable water test was carried out to determine the degree of hydration of cement paste with and without micronized sands. The influence of different finenesses of sand particles,240 m2/kg,400 m2/kg and 1 300 m2/kg,and different curing ages were investigated. The SEM image analysis was used to characterize the morphological changes of microstructure by the presence of the micronized sand during the cement hydration process. Hydration reaction is enhanced by the use of inert micronized sands. The fineness of micronized sands influences the degree of hydration a lot. The fineness factor has been taken into account in the simulation. There is a clear interface area between sand particle and hydration products.

关键词： micronized sand microstructure fineness cementitious materials

RESEARCH ON FADING CHARACTERISTICS OF ALANINE/ESR DOSIMETERS IN HIGH DOSE RANGE

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Nuclear Science and Techniques 1993年第1期4卷 4-10页

作者：陈丽姝 H.Tachibana y.Haruyama China Institute of Atomic Energy Beijing 102413 China Japanese Atomic Energy Research Institute Takasaki Japan

The present work has dealt extensively and systematically with the fading characteristics of polystyrene-alanine dosimeters irradiated at different dose rates and total doses under various temperatures (10-70 ℃) and stored a period of time in different conditions (5, 25, room temperature, 40 ℃). Detail investigation on this effect in practical irradiation condition is very important. Because it is difficult to correct this effect using correction coefficients so far. So the temperature coefficients and fading rates have been given along with a lot of experimental data to try to make approximation of radical formation or decay behavior.

关键词： Radiation processing dosimetry PS-alanine dosimeter ESR Transfer dosimeter Temperature coefficients Fading behaviour

Construction quality acceptance performance-related specifications for chip seals

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Journal of Traffic and Transportation Engineering(English Edition) 2019年第4期6卷 337-348页

作者： Javon Adams Cassie Castorena y.Richard Kim Department of Civil Construction and Environmental Engineering North Carolina State University

The research described herein details the establishment of a framework for construction quality acceptance performance-related specifications(PRS) for chip seal surface treatments. This paper establishes acceptance quality characteristics(AQCs) and relationships between the AQCs and related chip seal performance measures. This work is a critical step in developing PRS for constructed chip seal treatments and establishing suitable guidelines for the PRS. The main objective of this paper is to determine appropriate test methods to evaluate each defined AQC. The relationships that are established between the AQCs and chip seal performance are used to define performance ranges and threshold values for a particular performance measure. These performance ranges and threshold values then can be used to define pay factors for the constructed chip seal section. The threshold values and pay factors for each AQC described herein are preliminary recommendations and require further validation prior to implementation. However, this research demonstrates how these PRS would be utilized to ensure acceptable chip seal construction quality in the *** developed construction quality acceptance PRS framework uses the percent within limits(PWL) concept to determine whether a chip seal lot passes the PRS threshold values and whether the contractor receives full pay, is subject to a pay penalty, or fails the construction PRS and must correct the chip seal within the first year in service, which constitutes the typical warranty period for contracted chip seal ***, recommendations are made as to the next steps in the development and validation of these construction quality acceptance PRS that are needed for implementation by contractors and state roadway maintenance agencies.

关键词： Performance-related specifications(PRS) Chip seal Construction Quality assurance Percent within limits

ISOTHERMAL PRECISION FORGING PROCESS OF ALUMINUM ALLOy CyLINDRICAL HOUSING

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中国有色金属学会会刊：英文版 1997年第3期7卷 124-127页

作者： Wang, Z Xue, KM Shan, DB Xu, FC Lu, y HARBIN INST TECHNOL SCH MAT SCI & ENGNHARBIN 150001PEOPLES R CHINA

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ＩＳＯＴＨＥＲＭＡＬＰＲＥＣＩＳＩＯＮＦＯＲＧＩＮＧＰＲＯＣＥＳＳＯＦＡＬＵＭＩＮＵＭＡＬＬＯＹＣＹＬＩＮＤＲＩＣＡＬＨＯＵＳＩＮＧ①ＷａｎｇＺｈｅｎ，ＸｕｅＫｅｍｉｎ，ＳｈａｎＤｅｂｉｎ，ＸｕＦｕｃｈａｎｇ，ＬｕＹａｎＳｃｈｏｏｌｏｆＭａｔｅｒｉａ...

关键词： aluminum alloy isothermal precision forging assembled die heating range

Synthesis and characterization of salt-impregnated anodic aluminum oxide composites for low-grade heat storage

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International Journal of Minerals,Metallurgy and Materials 2020年第1期27卷 112-118页

作者： Bengisu yilmaz Behiye yüksel Gökhan Orhan Devrim Aydin Zafer Utlu stanbul University-Cerrahpasa Faculty of EngineeringDepartment of Metallurgy and Materials EngineeringIstanbul 34320Turkey Istanbul Gedik University Department of Mechanical EngineeringIstanbul 34876Turkey Eastern Mediterranean University Faculty of EngineeringDepartment of Mechanical EngineeringMersin 10Turkey

Thermochemical heat storage(THS)systems have recently attracted a lot of attention in research and *** this study,an anodic aluminum oxide(AAO)template,fabricated by a two-step anodization method,was used for the first time as the matrix material for a THS *** salts were studied as thermochemical materials for their suitability in low-grade heat storage application driven by solar energy for an open *** were prepared by absorbing CaCl2,MgCl2,LiCl,LiNO3 and mixtures of these salts under a vacuum in an AAO *** Emission Scanning Electron Microscopy was used to examine the morphology of the produced AAO *** energy storage capacities of the composites were characterized using a differential scanning *** analysis showed that anodized Al plates were suitable matrix materials for THS systems,and composite sorbent prepared with a 1:1 ratio LiCl/LiNO3 salt mixture had the highest energy value among all composites,with an energy density of 468.1 k J·kg-1.

关键词： thermal energy storage salt impregnation thermochemical heat storage anodizing salt in matrix

STUDy OF MICROSTRUCTURES OF DEFORMED Ti-48Al-Mn-Nb ALLOy

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Acta Metallurgica Sinica(English Letters) 1996年第4期9卷 267-271页

作者： D Song,G.y Zeng and X. y Sun (Material Testing Centre, Northeastern University,Shenyang 110006,China )

In the present paper, the microstructures of the two-phase alloy specimens of Ti-48AlMn-Nb, deformed at room temperature, 700℃and 900℃,have been investigated by using an EM400T transmission electron microscope. For specimens deformed at room temperature it is observed that (1/2) [011] superdislocation, normal (1/2) [110] dislocations, stacking fault band and a few twins etc. formed mainly in r-phase and a (1/2) [011] superdislocation preferentially decomposes into two partial dislocations with an antiphase boundary between them, which makes the dislocation difficult to move. The normal (1/2) [110] dislocations move with a long dragging tail behind them and have a low mobility In addition, the existence of a few twins implies a low mobility of (1/6) twin dislocations, which leads to low plasticity of the allow. For samples deformed above 700℃,(1/2) [110] dislocations are in majority in the r-phase and exhibit short and bending dislocation segments without dragging tails,which may have resulted from an increased mobility of (1/2) [110] dislocations due to thermal activation. Meanwhile, (1/2) [011]superdislocation disappears, the mobility of (1/6) dislocations is greatly increased, and thus a lot of twins are produced in r-phase. These make the plasticity of the alloy notably enhanced. The laminated structures in the alloy may be transformed into stacking fault bands during deformation at room temperature and the deformation above 700℃leads to the generation of a great quantity of twins.

关键词： dislocation stacking fault twin TiAl alloy

A Novel Convolutional Neural Network Model for Malaria Cell Images Classification

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Computers, Materials & Continua 2022年第9期72卷 5889-5907页

作者： Esraa Hassan Mahmoud y.Shams Noha A.Hikal Samir Elmougy Faculty of Artificial Intelligence Kafrelsheikh UniversityKafrelsheikh33511Egypt Department of Information Technology Faculty of Computers and InformationMansoura UniversityMansoura35516Egypt Department of Computer Science Faculty of Computers and InformationMansoura UniversityMansoura35516Egypt

Infectious diseases are an imminent danger that faces human beings around the *** is considered a highly contagious *** diagnosis of various diseases,including malaria,was performed manually,but it required a lot of time and had some human ***,there is a need to investigate an efficient and fast automatic diagnosis *** deep learning algorithms can provide a solution in which they can learn complex image patterns and have a rapid improvement in medical image *** study proposed a Convolutional Neural Network(CNN)model to detect malaria automatically.A Malaria Convolutional Neural Network(MCNN)model is proposed in this work to classify the infected *** focuses on detecting infected cells,which aids in the computation of parasitemia,or infection *** proposed model achieved 0.9929,0.9848,0.9859,0.9924,0.0152,0.0141,0.0071,0.9890,0.9894,and 0.9780 in terms of specificity,sensitivity,precision,accuracy,F1-score,and Matthews Correlation Coefficient,respectively.A comparison was carried out between the proposed model and some recent works in the *** comparison demonstrates that the proposed model outperforms the compared works in terms of evaluation metrics.

关键词： Deep learning malaria dataset diagnostic medical approach

Exit problem of stochastic SIR model with limited medical resource

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Theoretical & Applied Mechanics Letters 2023年第1期13卷 8-13页

作者： y.C.Mao X.B.Liu State Key Lab of Mechanics and Control for Mechanical Structures College of Aerospace EngineeringNanjing University of Aeronautics and AstronauticsNanjing 210016China

Nonlinearity and randomness are both the essential attributes for the real world,and the case is the same for the models of infectious diseases,for which the deterministic models can not give a complete picture of the ***,although there has been a lot of work on stochastic epidemic models,most of them focus mainly on qualitative properties,which makes us somewhat ignore the original meaning of the parameter *** this paper we extend the classic susceptible-infectious-removed(SIR)epidemic model by adding a white noise excitation and then we utilize the large deviation theory to quantitatively study the long-term coexistence exit problem with ***,in order to extend the meaning of parameters in the corresponding deterministic system,we tentatively introduce two new thresholds which then prove rational.

关键词： Stochastic epidemic model Stochastic dynamical system Large deviation theory Exit problem