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Unique microstructure and thermal insulation property of a novel waste-utilized foam ceramic

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Journal of Materials Science & Technology 2020年第13期47卷 175-179页

作者： F.H.Kuang S.M.Wang C.Gao H.B.Zhang r.K.ren J.l.ren J.Tong Y.M.liu Department of Materials Science and Engineering University of Science&Technology BeijingBeijing 100083China China Building Materials Academy Beijing 100024China China Institute for radiation Protection Taiyuan 030006China

A characteristic CaO-Al2O3-SiO2 based foam ceramic was prepared by melt-foaming with solid wastes as main raw *** similarity to sandwich hole wall microstructure of this novel thermal insulating material was presented and the relationships between this unique microstructure and porosity,density,thermal conductivity and strength were *** the measured and theoretical values with that of the traditional foam ceramic,it can be found that,for the matching of fine skeleton with hole wall,this original sandwich structure can reduce thermal conductivity and increase flexural strength effectively.

关键词： Foam ceramic Density Porosity Strength Thermal conductivity Sandwich structure

Collimated quasi-monochromatic beams of accelerated electrons in the interaction of a weak-contrast intense femtosecond laser pulse with a metal foil

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High Power laser Science and Engineering 2013年第2期1卷 80-87页

作者： Yu.A.Malkov A.N.Stepanov D.A.Yashunin l.P.Pugachev P.r.levashov N.E.Andreev K.Yu.Platonov A.A.Andreev Institute of Applied Physics Russian Academy of Sciences ul. Ulyanova 46 603950 Nizhny Novgorod Russia Joint Institute of High Temperatures Russian Academy of Sciences Izhorskaya ul. 13 125412 Moscow Russia Federal State Unitary Enterprise ‘‘Scientific and Industrial Corporation ‘Vavilov State Optical Institute’’’ Birzhevay liniya 12 St 199034 Petersburg Russia

We demonstrated experimentally the formation of monoenergetic beams of accelerated electrons by focusing femtosecond laser radiation with an intensity of 2×1017W/cm2onto the edge of an aluminum *** electrons had energy distributions peaking in the 0.2–0.8 MeV range with energy spread less than 20%.The acceleration mechanism related to the generation of a plasma wave as a result of self-modulation instability of a laser pulse in a dense plasma formed by a prepulse(arriving 12 ns before the main pulse)is ***-dimensional and two-dimensional Particle in Cell(PIC)simulations of the laser–plasma interaction showed that effective excitation of a plasma wave as well as trapping and acceleration of an electron beam with an energy on the order of 1 MeV may occur in the presence of sharp gradients in plasma density and in the temporal shape of the pulse.

关键词： acceleration of electrons femtosecond laser radiation plasma wave self-modulation instability

MODElING MICrOBUBBlE DYNAMICS IN BIOMEDICAl APPlICATIONS

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Journal of Hydrodynamics 2012年第2期24卷 169-183页

作者： CHAHINE Georges l. HSIAO Chao-Tsung Dynaflow Inc.JessupMaryland 20794USA

Controlling microbubble dynamics to produce desirable biomedical outcomes when and where necessary and avoid deleterious effects requires advanced knowledge, which can be achieved only through a combination of experimental and numerical/ analytical techniques. The present communication presents a multi-physics approach to study the dynamics combining viscous- inviscid effects, liquid and structure dynamics, and multi bubble interaction. While complex numerical tools are developed and used, the study aims at identifying the key parameters influencing the dynamics, which need to be included in simpler models.

关键词： microbubble biological contrast agents thick shell ultrasound

MECHANISM AND KINETICS OF TrANSFOrMATION OF AlUMINA INClUSIONS BY CAlCIUM TrEATMENT

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Acta Metallurgica Sinica(English letters) 2006年第1期19卷 1-8页

作者： Z.J. Han l. liu M. lind l. Holappa Central Iron and Steel research Institute Beijing 100081 China laboratory of Metallurgy Helsinki University of Technology P.O. Box 6200Espoo 02015 Finland

The basic mechanism and kinetics of the transformation process of alumina inclusions in steel was reported when calcium introduced into the steel by wire feeding orpowder injection. To clarify the mechanisms model, experiments were performed by studying reactions between AltOs and CaO in a laboratory furnace and by performing calcium treatments in an 8kg induction furnace for Al deoxidised melt. The phases formed during the reaction between Al2O3 and CaO were examined by SEM-EDS （scanning electron microscope-energy dispersive spectrometer）, and the reaction sequence of Al2O3=〉 CA6=〉 CA2 =〉 CA =〉 CAx（l） was discussed in term of the experimental observations. The kinetics of the reaction of calcium with alumina inclusions were simulated by immersing alumina plates in a Ca treated steel melt in the induction furnace. results were compared with observations of real inclusion transformation. A kinetic model was proposed based on the results.

关键词： mechanism kinetics alumina inclusion transformation

Multi-tissue transcriptomics of a unique monozygotic discordant twin case of severe progressive osseous heteroplasia

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Genes & Diseases 2024年第3期11卷 22-25页

作者： Alberto Gomez-Carballa Maria Jose Curras-Tuala Sara Pischedda Miriam Cebey-lopez Jose Gomez-rial Irene rivero-Cale Jacobo Pardo-seco Xabier Bello Sandra Viz-lasheras Antonio Justicia-Grande Julian Montoto-louzao Alba Camino-Mera Isabel Ferreiros-Vidal Maximo Fraga Jose rAntunez rodolfo Gomez Federico Martinon-Torres Antonio Salas Genetics Vaccines and Infections Research Group(GENVIP)Instituto de Investigacion Sanitaria de SantiagoSantiagode CompostelaGalicia 15706Spain Translational Pediatrics and Infectious Diseases Department of PediatricsHospital Clinico Universitario de Santiago de CompostelaServicio Galego de Saude(SERGAS)Galicia 15706Spain laboratorio de Inmunologia Servicio de Andlisis ClinicosHospital Clinico Universitario de Santiago de CompostelaServicio Galego de Saude(SERGAS)Galicia 15706Spain Unidade de Xenetica Instituto de Ciencias Forenses(INCIFOR)Facultade de MedicinaUniversidade de Santiago de Compostelaand GenPoB Research GroupInstituto de Investigacion SanitariaHospital Clinico Universitario de Santiago de CompostelaServicio Galego de Saude(SERGAS)Galicia 15706Spain Musculoskeletal Pathology Group Instituto de Investigacion Sanitaria de SantiagoServicio Galego de Saude(SERGAS)Santiago de CompostelaGalicia 15706Spain Department of Pathology Hospital Clinico Universitario de Santiago de Compostela(SERGAS)Galicia 15706Spain Unidad Integrada de BiobancosBiomodelos 3D y Modelos Animales IDIS(lnstituto de Investigacion Sanitaria de Santiagode Compostela)Galicia15706Spain Centro de Investigacion Biomedica en red de Enfermedades respiratorias(CIBEr-ES) MadridSpain

Progressive osseous heteroplasia(POH)is an ultra-rare autosomal dominant disabling disorder characterized by heterotopic ossification(HO).It is caused by heterozygous inactivating mutations in the GNAS(guanine nucleotide-binding protein alpha-stimulating activity polypeptide)***,the molecular mechanisms underlying HO remain poorly *** a treatment for POH is not yet available,the identification of the mechanisms driving POH in affected tissues using gene expression may be of great help to underestand the molecular basis of POH and develop new therapeutic approaches.

关键词： stimulating driving asi

Deep Neural Network Driven Automated Underwater Object Detection

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Computers, Materials & Continua 2022年第3期70卷 5251-5267页

作者： Ajisha Mathias Samiappan Dhanalakshmi r.Kumar r.Narayanamoorthi Department of Electronics and Communication Engineering SRMInstitute of Science and TechnologyKattankulathurChennai603203India Department of Electrical and Electronics Engineering SRMInstitute of Science and TechnologyKattankulathurChennai603203India

Object recognition and computer vision techniques for automated object identification are attracting marine biologist’s interest as a quicker and easier tool for estimating the fish abundance in marine ***,the biggest problem posed by unrestricted aquatic imaging is low luminance,turbidity,background ambiguity,and context camouflage,which make traditional approaches rely on their efficiency due to inaccurate detection or elevated false-positive *** address these challenges,we suggest a systemic approach to merge visual features and Gaussian mixture models with You Only look Once(YOlOv3)deep network,a coherent strategy for recognizing fish in challenging underwater *** an image restoration phase,pre-processing based on diffraction correction is primarily applied to *** YOlOv3 based object recognition system is used to identify fish *** objects in the background that are camouflaged are often overlooked by the YOlOv3 model.A proposed Bi-dimensional Empirical Mode Decomposition(BEMD)algorithm,adapted by Gaussian mixture models,and integrating the results of YOlOv3 improves detection efficiency of the proposed automated underwater object detection *** proposed approach was tested on four challenging video datasets,the life Cross language Evaluation Forum(ClEF)benchmark from the F4K data repository,the University of Western Australia(UWA)dataset,the bubble vision dataset and theDeepFish *** accuracy for fish identification is 98.5 percent,96.77 percent,97.99 percent and 95.3 percent respectively for the various datasets which demonstrate the feasibility of our proposed automated underwater object detection method.

关键词： Underwater images diffraction correction marine object recognition gaussian mixture model image restoration YOlO

A photolysis coefficient for characterizing the response of aqueous constituents to photolysis

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Frontiers of Environmental Science & Engineering 2016年第3期10卷 428-437页

作者： David r. HOKANSON Ke lI r. rhodes TrUSSEll Trussell Technologies Inc. Pasadena CA 91101 USA College of Engineering University of Georgia Athens GA 30602 USA

UV photolysis and UV based advanced oxidation processes （AOPs） are gaining more and more attention for drinking water treatment. Quantum yield （Ф） and molar absorption coefficient （ε） are the two critical parameters measuring the effectiveness of photolysis of a compound. The product of the two was proposed as a fundamental measure of a constituent＇s amenability to transformation by photolysis. It was shown that this product, named the photolysis coefficient, kp, can be determined using standard bench tests and captures the properties that govern a constituent＇s transformation when exposed to light. The development showed the photolysis coefficient to be equally useful for microbiological, inorganic and organic constituents. Values of kp calculated by the authors based on quantum yield and molar absorption coefficient data from the literature were summarized. Photolysis coefficients among microorganisms ranged from 8500 to more than 600000 and are far higher than for inorganic and organic compounds, which varied over a range of approximately 10 to 1000 and are much less sensitive to UV photolysis than the microorganisms.

关键词： UV photolysis disinfection advanced oxidation N-nitrosodimethylamine quantum yield absorption coefficient

Density and Seasonal Dynamics of Bemisia tabaci(Gennadius) Mediterranean on Common Crops and Weeds Around Cotton Fields in Northern China

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Journal of Integrative Agriculture 2014年第10期13卷 2211-2220页

作者： ZHANG Xiao-ming YANG Nian-wan WAN Fang-hao Gabor l lvei State Key laboratory for Biology of Plant Diseases and Insect Pests Institute of Plant ProtectionChinese Academy of Agricultural Sciences Department of Agroecology Aarhus UniversityFlakkebjerg Research Centre DK-4200 SlagelseDenmark

The density seasonal dynamics of Bemisia tabaci MED were evaluated over two years in a cotton-growing area in langfang, Hebei Province, northern China on cotton （Gossypium hirsutum l.） and six other co-occurring common plants, common ragweed （Ambrosia artemisiifolia l.）, piemarker （Abutilon theophrasti Medicus）, sunflower （Helianthus annuus l.）, sweet potato （Ipomoea batatas l.）, soybean （Glycine max l.）, and maize （Zea mays l.）. The whitefly species identity was repeatedly tested and confirmed; seasonal dynamics on the various host plants were standardized by the quartile method. B. tabaci MED appeared on weeds （the common ragweed and piemarker） about 10 days earlier than on cotton, or the other cultivated plants. The peak population densities were observed over a span of 2 to 3 weeks on cotton, starting in early （2010） or mid-August （2011）. The common ragweed growing adjacent to cotton supported the highest B. tabaci densities （no. on 100 cm2 leaf surface）, 12-22 fold higher than on cotton itself. Sunflower supported more B. tabaci than the other plants, and about 1.5-2 fold higher than cotton did, Our results indicate that weeds （esp. the common ragweed） around cotton fields could increase the population density of B. tabaci MED on cotton, while sunflower could act as a trap crop for decreasing pest pressure on cotton.

关键词： Bemisia tabaci whitefly cotton sunflower ragweed population dynamics seasonal dynamics quartile method

Effect of densification distribution on the Young's modulus of porous coatings after nano-indentation

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Acta Metallurgica Sinica(English letters) 2012年第5期25卷 383-390页

作者： Xiaojuan l U Ping XIAO Haiyan lI School of Environment Science and Engineering North China Electric Power University Yonghua North Street Baoding 071000 China School of Materials The University of Manchester Manchester M1 7HS UK School of Mechanical Aerospace and Civil Engineering The University of Manchester P.O. Box 88Sackville Street Manchester M60 1QD UK

Nano-indentation of a porous ceramic coating leads to crushing and densification of the coating under the indenter. In this work, finite element simulations of indentation on the porous coating have been carried out to study the effect of the size and dis- tribution of densification on Youngts modulus measured by nano-indentation. Two totally different distribution patterns have been simulated in this work. In the case of gradient densification, the Youngts modulus increased by 8.6% when the densifi- cation has occurred in the maximum influenced area. While the Young^s modulus increased by 2% with a uniformed densification. Examinations of the cross-section of the coatings have suggested that the densification after the indentation is close to the second model. The measured Young＇s modulus could have differed by 2%. The effect of densification on the Young＇s modulus measured by using nano-indentation is strongly dependent on the densification patterns of the porous coating.

关键词： Film Mechanical property Finite element simulation Porosity Electron Microscopy