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ON THE IDENTIFICATION OF RESIDUAL ImPACT PROPERTIES OF mATERIALS By ACOUSTO-ULTRASONICS——A PATTERN RECOGNITION APPROACH

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Acta mechanica Sinica 1995年第1期11卷 34-43页

作者： G.J.molina y.m.Haddad Dept.of mechanical Engineering University of OttawaOttawaCanada K1N 6N5

This paper deals with the application of Acousto-ultrasonics,in con- junction with Pattern Recognition and Classification techniques,to the identification of residual impact properties of a class of polymeric material,namely,Polyvinylchlo- ride(PVC).PVC specimens of different low-energy repeated impact damage states are processed by Acousto-ultrasonics(AU)to retrieve AU signals in the form of dig- italized *** AU signals are grouped as distinct classes,each pertaining to a known level of repeated impact *** features of these AU signals are used to build Pattern Recognition(PR)*** classifiers are used to identify unknown damage states in other PVC specimens by classifying the re- trieved AU signals as belonging to one of the *** obtained results indicate that Acousto-ultrasonics in combination with Pattern Recognition and Classification techniques can be used for the quantitative non-destructive identification of damage states in PVC specimens of unknown low-energy repeated impact conditions.

关键词： pattern recognition acousto-ultrasonics impact damage quantitative non-destructive examination

Nanotexturing and Wettability Ageing of Polypropylene Surfaces modified by Oxygen Capacitively Coupled Radio Frequency Plasma

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Journal of materials Science & Technology 2014年第10期30卷 965-972页

作者： y.P.Li m.K.Lei Surface Engineering Laboratory School of Materials Science and EngineeringDalian University of Technology

Polypropylene （PP） was treated by an oxygen capacitively coupled radio frequency plasma （CCP） under a radio frequency （RF） power of 200 W for exposure time of 1, 5, and 10 rain. The ageing process of the plasma- treated PP was studied at an ageing temperature of 90 ~C during an ageing time up to 25 h. The formation of the nanotextures with different geometry and aspect ratio and the grafting of large number of oxygen- containing groups were achieved on as-treated PP surfaces under the oxygen CCP treatment for the increased exposure time. The hydrophilicity on the as-treated PP surfaces with the stable nanotextures was rapidly depressed during the ageing process at 90 ℃ due to the restructuring of chemical composition. The surface restructuring rate was dependent on the aspect ratio and the oxygen-containing groups on the nanotextured PP with increasing exposure time. The hydrophobic over-recovery to high hydrophobicity and superhydrophobicity were observed on the post-aged surfaces with the stable nanofibrils from as-treated hydrophilic surfaces. The superhydrophobicity with the low water adhesion was achieved on the post-aged surfaces preserving the nanofibrils with high aspect ratio and large distance due to the decrease of the oxygen-containing groups after the surface restructuring.

关键词： Polypropylene Plasma nanotexturing Ageing Surface restructuring Superhydrophobicity

Optical Constant and Electrical Resistivity of Annealed Sn3Sb2S6 Thin Films

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Acta metallurgica Sinica(English Letters) 2016年第3期29卷 287-294页

作者： y.Fadhli A.Rabhi m.Kanzari Laboratoire de Photovoltaique et materiaux Semi-conducteurs-ENIT BP 37 Le belvedere 1002 Tunis Tunisia Laboratoire de Photovoltaiques et materiaux Semi-conducteurs-ENIT-IPEITunis montfleury Universite de Tunis Tunis Tunisia

In this study,we report the annealing effects on the physical properties of Sn_3Sb_2S_6 thin ***_3Sb_2S_6 thin films were prepared onto non-heated glass substrates via thermal evaporation *** as-deposited films were annealed in air for 1 h in the temperature range from 100 to 300 °C.X-ray diffraction results show that the crystallinity of the thin films increased after *** microstructure parameters crystallite size,dislocation density,lattice strain and stacking fault probability were *** optical properties were obtained from the analysis of the experimental recorded transmittance and reflectance spectral data over the wavelength range 300–1800 *** absorption coefficient（10~5cm^（-1）） reached to the visible and near-IR spectral range.A decrease in optical band gap from 1.92 to 1.71 e V by increasing the air annealing temperature was *** energy E_o and dispersion energy E_d of the films after annealing were estimated according to the model of Wemple–Di Domenico single ***–Fan model was applied to determine the electron free carrier susceptibility and the ratio of carrier concentration to the effective *** layers annealed at temperatures 〉150 ℃ undergo abrupt changes in their electrical properties and exhibit a resistive hysteresis *** properties confer to the material interest perspectives for its application in diverse advanced technologies such as photovoltaic applications and optical storage.

关键词： Thin films Sn_3Sb_2S_6 Optical constants Resistivity Hysteresis

Effect of post-bond heat treatment on the microstructure and high temperature mechanical property of a TLP bonded γ'-strengthened co-based single crystal superalloy

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Journal of materials Science & Technology 2021年第21期80卷 244-258页

作者： S.y.Wang y.Sun C.y.Cui X.F.Sun y.Z Zhou y.m.ma H.L.An Institute of metal Research Chinese Academy of SciencesShenyang 110016China School of materials Science and Engineering University of Science and Technology of ChinaHefei 230026China Harbin Welding Institute China Academy of Machinery Science and TechnologyHarbin 150028China

Post-bond heat treatment(PBHT) applied to a transient liquid phase(TLP) bonding joint is an effective approach to remove the brittle borides and improve its ***,we proposed two types of PBHT strategies to obtain a TLP bonded γ'-strengthened Co-based single crystal superalloy,and the microstructural characteristics and tensile properties of the two heat treated joints were compared to identify the optimal PBHT *** evolution of the brittle boride in the joint after the PBHT was studied by using in-situ *** experimental results allowed to provide a theoretic model to quantitatively evaluate the distribution of the brittle phase after the optimal PBHT and analyze the joint fractures to understand the failure *** obtained results revealed that a post-bond solid solution treatment performed to the joint at a high temperature(over 1275℃) could decrease the area fraction of the boride from 7.2 % to 1.4 % and increase the elongation from 1.9 % to 7.8 %.This work emphasizes the relevance of solid solution temperature when a PBHT strategy is applied.

关键词： Transient liquid phase(TLP) γ'-strengthened co-based single crystal superalloy Heat treatment sequence Brittle boride Tensile property

Coupled pile soil interaction analysis in undrained condition

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Journal of Central South University 2013年第5期20卷 1376-1383页

作者： m.y.Fattah F.A.Salman y.J.Al-Shakarchi A.m.Raheem Building and Construction Engineering Department University of Technology Department of Civil Engineering Faculty of EngineeringUniversity of Malaya Department of Civil Engineering College of EngineeringUniversity of Baghdad Department of Civil Engineering College of EngineeringUniversity of Kirkuk

The effective stress method is developed to predict the axial capacity of piles in clay. The effective stress state changes due to the resulting pore pressure change and therefore, the strength and stiffness of the soil will change. In this work, the finite element method is utilized as a tool for the analysis of pile-soil systems in undrained condition. The computer program CRISP was developed to suit the problem requirements. CRISP uses the finite element technique and allows predictions to be made of ground deformation using critical state theories. Eight-node isoparametric element was added to the program in addition to the slip element. A pile loading problem was solved in which the pile-soil system is analyzed in undrained condition. The pile is modelled as elastic-plastic material, while the soil is assumed to follow the modified Cam clay model. During undrained loading condition, the settlement values increase by 22% when slip elements are used. The surface settlement increases by about three times when the load is doubled and the surface settlement at all points increases when using slip elements due to the mode of motion which allows smooth movement of the adjacent soil with respect to the pile. The vertical displacement increases as the distance decreases from the pile and negligible values are obtained beyond 10D (where D is the pile diameter) from the center of the pile and these values are slightly increased when slip elements are used. The vertical effective stress along a section at a distance D from the pile center is approximately the same for all load increments and lower values of effective vertical stress can be obtained when slip elements are used.

关键词： pile finite element coupled analysis undrained condition

Spray deposited yttrium incorporated TiO_(2) photoelectrode for efficient photoelectrocatalytic degradation of organic pollutants

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Journal of Rare Earths 2023年第12期41卷 1929-1937,I0004页

作者： N.A.Narewadikar R.S.Pedanekar V.G.Parale H.H.park K.y.Rajpure Electrochemical materials Laboratory Department of PhysicsShivaji UniversityKolhapur46004India Department of materials Science and Engineering Yonsei University Seoul037322South Korea

This work presents result on yttrium-doped titanium dioxide(yTO) thin films using a cost-effective spray pyrolysis technique for the photoelectrocatalytic degradation of phthalic acid(PA) and benzoic acid(BA).The physicochemical properties of yTO thin films were studied using X-ray diffraction,Raman spectroscopy,X-ray photoelectron spectroscopy,field-emission scanning electron microscopy,UV-vis spectroscopy,*** obtained results confirm the presence of yttrium in the host *** band bending and flat band positions were studied using mott-Schottky *** film with 1% doping amount shows the highest degradation efficiency for both the model pollutants compared to TiO_(2).The stability of 1% yTO film confirms excellent performance analyzed by recycling tests using a UV-vis *** results highlight the significance of rare earth metal doping in TiO_(2)for improved photoelectrocatalytic degradation efficiency.

关键词： Doping Organic pollutant Spray pyrolysis Thin film TiO_(2) Rare earths

Impact of Zika virus non-structural protein mutations on hippocampal damage

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Neural Regeneration Research 2025年第8期20卷 2307-2308页

作者： Larissa m.G.Cassiano Roney S.Coimbra Neurogenômica/Imunopatologia Instituto RenéRachouFiocruzBelo HorizonteBrazil Departamento de Bioquímica e Imunologia Instituto de Ciências BiológicasUniversidade Federal de Minas GeraisBelo HorizonteBrazil

The Zika virus(ZIKV),a member of the Flaviviridae family,attracted worldwide attention for its connection to severe neurological effects,notably microcephaly in newborns,first reported during the 2015 epidemic in ***,its impact goes beyond fetal and neonatal abnormalities,also affecting the central nervous system(CNS)in both children and adults,leading to enduring cognitive and behavioral impairments.

关键词： damage fetal neonatal

Contamination of Harvested Organs in Root Crops Grown on Chlordecone-Polluted Soils

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Pedosphere 2012年第4期22卷 562-571页

作者： y. m. CABIDOCHE m. LESUEUR-JANNOyER Research Unit 1321 Agrosystèmes Tropicaux INRA Duclos 97170 Petit-Bourg (France) Ple de Recherche Agro-Environnementale de martinique CIRAD Petit-Morne BP 214 97285 Lamentin (France) UR103 Fonctionnement Agroécologique et Performances des Systèmes de Culture Horticoles CIRAD TA B-103/PS4 Bd de la Lironde 34389 Montpellier Cedex 5 (France)

Chlordecone, one of the most persistent organochlorine pesticides, was applied between 1972 and 1993 in banana fields in the French West Indies, which results in long-term pollution of soils and contamination of waters, aquatic biota, and crops. As human exposure to chlordecone is mainly due to food contamination, early research was focused on chlordecone transfer to crops. Field trials were conducted to investigate chlordecone contamination of yam, sweet potato, turnip, and radish grown on a Ferralic Nitisol polluted by chlordecone. We also carried out trials on yam, courgette, and tomato under greenhouse conditions with homogenized Andosol and Nitisol, polluted by chlordecone to various extents. Our results indicated that i) all tubers were contaminated in accordance with the chlordecone content of the soils; ii) the plant contamination capacity of the Nitisol was greater than that of the Andosol; and iii) whatever the soil type, tuber contamination was related to the soil volumetric content of dissolved chlordecone. Nevertheless, no tubers showed sufficient chlordecone uptake for efficient soil decontamination by means of plant extraction. Soil contact accounted for most of the root crop contamination, which was inversely proportional to the tuber size. Internal transfer might also increase root crop contamination when the root central cylinder contained raw sap flow, as in the case of turnip or radish. Courgette fruits showed high contamination without soil contact. Thus, further research is needed to explore the pattern of both below- and aboveground plant chlordecone contamination and assess the hypothesis of its correlation with sap flow. Finally, we used our results to build a decisionmaking tool for farmers, relating soil pollution with the maximal contamination of the harvested organs to predict crop contamination and thus assisting farmers in making crop choices at planting in order to conform with the European Union's regulations.

关键词： crop contamination fruit organochlorine pesticide soil pollution tuberbidoche. y. m. and Lesueur-Jannover. m. 2012. Contamination of harvested organs in

Quantum correlations and entanglement in coupled optomechanical resonators with photon hopping via Gaussian interferometric power analysis

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Chinese Physics B 2024年第5期33卷 204-211页

作者： y.Lahlou B.maroufi m.Daoud LPHE-mS Department of PhysicsFaculty of SciencesMohammed V UniversityRabatMorocco LPmS Department of PhysicsFaculty of SciencesIbn Tofail UniversityKénitraMorocco

Quantum correlations that surpass entanglement are of great importance in the realms of quantum information processing and quantum ***,for quantum systems prepared in pure states,it is difficult to differentiate between quantum entanglement and quantum ***,this indistinguishability is no longer holds for mixed *** contribute to a better understanding of this differentiation,we have explored a simple model for both generating and measuring these quantum *** study concerns two macroscopic mechanical resonators placed in separate Fabry–Pérot cavities,coupled through the photon hopping *** system offers a comprehensively way to investigate and quantify quantum correlations beyond entanglement between these mechanical *** key ingredient in analyzing quantum correlation in this system is the global covariance *** forms the basis for computing two essential metrics:the logarithmic negativity(E_(N)^(m))and the Gaussian interferometric power(P_(G)^(m)).These metrics provide the tools to measure the degree of quantum entanglement and quantum correlations,*** study reveals that the Gaussian interferometric power(P_(G)^(m))proves to be a more suitable metric for characterizing quantum correlations among the mechanical modes in an optomechanical quantum system,particularly in scenarios featuring resilient photon hopping.

关键词： quantum correlations entanglement Gaussian interferometric power logarithmic negativity optomechanics photon hopping