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Journal of Environmental Sciences 2016年第3期28卷 59-68页

作者： Hicham Zaitan Marie Hélène Manero Héctor Valdés Laboratoire de Chirmie de la Matiere Condensee(LCMC) Faculte des Sciences et TechniquesUniversite Sidi Mohamed Ben AbdellahB.P.2202FesMaroc Universite de Toulouse INPTUPSLaboratoire de Genie Chimique4Allee Emile MonsoF-31030 ToulouseFrance CNRS Laboratoire de Genie ChimiqueF-31030 ToulouseFrance Laboratorio de Tecnologias Limpias(F.Ingenieria) Universidad Catolica de la Santisima ConcepcionAlonso de Ribera 2850ConcepcionChile

In this study,a hydrophobic synthetic zeolite,namely ZSM-5 is chosen as an adsorbent/catalyst for toluene *** results showed that toluene adsorption onto ZSM-5 was favourable,following a Langmuir adsorption isotherm ***-5 zeolite was regenerated using gaseous ozone at low *** toluene was oxidised,releasing mainly CO_2 and H_*** of oxidation by-products such as acetic acid and acetaldehyde were formed and remained adsorbed after the oxidativate regeneration with *** four successive cycles of adsorption/ozonation,the adsorption efficiency was not affected（92%-99%）.These results showed that volatile organic compound（VOC）removal by adsorption onto ZSM-5 zeolite followed by ozone regeneration could be used as a promising hybrid process for the control of VOC emissions in terms of efficiency.

关键词： Adsorption Ozone Toluene VOCs Zeolite

The Use of Rank Histograms and MVL Diagrams to Characterize Ensemble Evolution in Weather Forecasting

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Advances in Atmospheric Sciences 2010年第6期27卷 1425-1437页

作者： Jorge A.REVELLI Miguel A.RODRIGUEZ Horacio S.WIO Instituto de Fisica de Cantabria (UC and CSIC) Avda.de los Castross/nE-39005 SantanderSpain

Rank Histograms are suitable tools to assess the quality of ensembles within an ensemble prediction system or framework. By counting the rank of a given variable in the ensemble, we are basically making a sample analysis, which does not allow us to distinguish if the origin of its variability is external noise or comes from chaotic sources. The recently introduced Mean to Variance Logarithmic （MVL） Diagram accounts for the spatial variability, being very sensitive to the spatial localization produced by infinitesimal perturbations of spatiotemporal chaotic systems. By using as a benchmark a simple model subject to noise, we show the distinct information given by Rank Histograms and MVL Diagrams. Hence, the main effects of the external noise can be visualized in a graphic. From the MVL diagram we clearly observe a reduction of the amplitude growth rate and of the spatial localization （chaos suppression）, while from the Rank Histogram we observe changes in the reliability of the ensemble. We conclude that in a complex framework including spatiotemporal chaos and noise, both provide a more complete forecasting picture.

关键词： rank histogram MVL diagram ensemble evolution noise space-time chaos forecasting

Preparation and characteristics of a recycled cement-based superhydrophobic coating with dirt pickup resistance

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Science China(Technological Sciences) 2015年第6期58卷 1096-1104页

作者： GUO LiPing SUN Wei YU Tao FENG MuZai School of Materials Science and Engineering Southeast University Collaborative Innovation Center for Advanced civil Engineering Materials Jiangsu Key Laboratory of Construction Materials Wuxi Communication Engineering Co. Ltd. department of civil Environmental and Architectural Engineering The University of Kansas

We introduce a low-cost and effective technique that can transform waste cement-based dust into a superhydrophobic coating with dirt pickup resistance. An organic-inorganic hybrid superhydrophobic coating is prepared by the sol-gel method using methyltriethoxysilane as a precursor and waste cement-based dust as a film-forming material. Orthogonal experiments and a comprehensive scoring method were used to optimize the composition and production technologies. Our results show that this superhydrophobic organic-inorganic hybrid coating has an average static contact angle of 151.65° and low water adhesion. Related tests reveal that the dirt pickup resistance, washing resistance and film-substrate cohesion of this coating are also outstanding. The multi-scale physical and chemical mechanisms behind the properties of the coating are investigated. This recycled cement-based coating can be used as the external cover of engineering structures to protect them from corrosion.

关键词： recycled cement-based coating superhydrophobicity dirt pickup resistance washing resistance film-substrate cohesion multi-scale mechanisms

Hepatitis B Virus Genotype H and Environmental Factors Associated to the Low Prevalence of Hepatocellular Carcinoma in Mexico

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Journal of Cancer Therapy 2013年第2期4卷 367-376页

作者： Sonia Roman Nora Alma Fierro Laura E. Moreno-Luna Arturo Panduro department of Molecular Biology in Medicine Hospital Civil de Guadalajara Fray Antonio Alcalde Centro Universitario de Ciencias de la Salud Universidad de Guadalajara Guadalajara Mexico

Purpose: Hepatocellular carcinoma (HCC) is a leading health problem worldwide. Any agent causing chronic liver damage and cirrhosis is a risk factor for HCC. Genetic and environmental factors may be responsible for regional variations in the occurrence of HCC worldwide. The aim of this review was to describe the risk factors that may be contributing to low prevalence of HCC in the Mexican population. Methods: An electronic systematic search was conducted in four databases to retrieve studies on hepatocellular carcinoma inMexico. Results: Eighteen publications gave a total of 1042 HCC cases with a percentage that ranged from 0.25% to 1.87%. Cirrhosis was registered in 7 studies while the main etiologies were: HCV (66%), HBV (11%) and alcoholism (6.6%). Conclusions: In the last 50 years, the studies performed inMexicohave shown a very low incidence and/or mortality rate of HCC. These findings contrast from those reported in high endemic regions, such asAsia, where viral hepatitis and HCC are prevalent. One significant difference is the predominance of HBV genotype H in Mexico and HBV/B and C in Asia. InMexico, high endemic areas of HBV infection have been detected, mainly among the native population;however, infection seems to resolve very quickly, due to a prominent immunological response among the population. Other factors are that patients with liver cirrhosis die prematurely before that HCC can be detected. Furthermore, an environmental factor that may exert a protective effect against HCC, in spite of the high consumption of potentially aflatoxin-contaminated food products, is the neutralization of these substances by alkaline treatment. This study shows that genetic and environmental factors associated to HCC among the Mexican population are different from others reported worldwide.

关键词： HBV Genotype H HCV Alcoholism Aflatoxins Cirrhosis Nixtamalization

Vinyl sulfonyl chemistry-driven unidirectional transport of a macrocycle through a[2]rotaxane

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Organic Chemistry Frontiers 2022年第3期9卷 633-642页

作者： Arthur H.G.David Pablo García-Cerezo Araceli G.Campaña Francisco Santoyo-González Victor Blanco departamento de Química Orgánica Facultad de CienciasUnidad de Excelencia de Química Aplicada a Biomedicina y Medioambiente(UEQ)Universidad de Granada(UGR)Avda.Fuente Nueva S/N18071 GranadaSpain

By applying a combination of the coupling-and-decoupling(CAD)chemistry of the vinyl sulfonate group with the click thia-Michael addition to the vinyl sulfone group(MAVS)we performed the irreversible unidirectional transportation of the ring through the linear component in a[2]rotaxane by a chemically and pHdriven flashing energy ratchet mechanism.

关键词： mechanism unidirectional chemistry

Dynamic properties of polyurethane foam adhesive-reinforced gravels

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Science China(Technological Sciences) 2021年第3期64卷 535-547页

作者： LIU Ping MENG MinQiang XIAO Yang LIU HanLong YANG Gui School of civil Engineering Ludong UniversityYantai 264025China School of civil Engineering Chongqing UniversityChongqing 400045China Key Laboratory of New Technology for Construction of Cities in Mountain Area Chongqing UniversityChongqing 400045China College of civil and Transportation Engineering Hohai UniversityNanjing 210098China Key Laboratory of Ministry of Education for Geomechanics and Embankment Engineering Hohai UniversityNanjing 210098China

Polyurethane foam adhesive(PFA)has been introduced as an alternative stabilizer in geotechnical applications because PFA can improve the engineering characteristics of soil by filling the pore space and generating adhesive bonding among the ***,the dynamic properties of PFA-reinforced soils are not well *** analyze the dynamic characteristics of PFA-reinforced gravels,a series of cyclic triaxial tests were carried out to investigate the shear modulus and damping ratio of PFA-reinforced gravels,and to determine the corresponding effects of the PFA content,confining pressure,consolidation stress ratio and loading *** results showed that the shear modulus increased,and the damping ratio decreased as the PFA content,confining pressure and consolidation stress ratio *** contrast,the effect of the loading frequency,which ranged from 0.05 to 1 Hz,was negligible.A modified hyperbolic empirical model can consider the effect of the PFA content on the maximum shear modulus and predict the relationship between the normalized shear modulus and the normalized shear strain was ***,the upper and lower bounds of the damping ratio were also proposed.

关键词： polyurethane foam adhesive gravel shear modulus damping ratio cyclic triaxial test

Field validation of UHPC layer in negative moment region of steel-concrete composite continuous girder bridge

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Frontiers of Structural and civil Engineering 2022年第6期16卷 744-761页

作者： Minghong QIU Xudong SHAO Weiye HU Yanping ZHU Husam H.HUSSEIN Yaobei HE Qiongwei LIU Key Laboratory for Wind and Bridge Engineering of Hunan Province College of Civil EngineeringHunan UniversityChangsha 410082China Zhejiang Provincial Institute of Communications Planning Design and Research Co.Ltd.Hangzhou 310013China department of civil Architectural and Environmental EngineeringMissouri University of Science and TechnologyRollaMO 65401USA department of civil Engineering Ohio UniversityAthensOH 45701-2979USA

Improving the cracking resistance of steel-normal concrete(NC)composite beams in the negative moment region is one of the main tasks in designing continuous composite beam(CCB)bridges due to the low tensile strength of the NC deck at pier *** study proposed an innovative structural configuration for the negative bending moment region in a steel-concrete CCB bridge with the aid of ultrahigh performance concrete(UHPC)*** order to investigate the feasibility and effectiveness of this new UHPC jointed structure in the negative bending moment region,field load testing was conducted on a newly built full-scale *** newly designed structural configuration was described in detail regarding the structural characteristics(cracking resistance,economy,durability,and constructability).In the field investigation,strains on the surface of the concrete bridge deck,rebar,and steel beam in the negative bending moment region,as well as mid-span deflection,were measured under different load ***,a finite element model for the four-span superstructure of the full-scale bridge was established and validated by the field test *** simulated results in terms of strains and mid-span deflection showed moderate consistency with the test *** field test and the finite element model results demonstrated that the new configuration with the UHPC layer provided an effective alternative for the negative bending moment region of the composite beam.

关键词： field test steel-concrete composite beam continuous girder bridge negative bending moment region ultrahigh performance concrete

Macroscopic and microscopic fracture features of concrete used in coal mine under chlorine salt erosion

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International Journal of Mining Science and Technology 2016年第3期26卷 455-459页

作者： Li Bing Yin Huiguang Mao Xianbiao Li Yan Zhang Lianying Liu Ruixue Qiu Peitao State Key Laboratory of Geomechanics and deep Underground Engineering China University of Mining & Technology School of civil Engineering Xuzhou Institute of Technology School of Mechanics & civil Engineering China University of Mining & Technology

The microscopic morphology and pore structure characteristics of concrete with composite admixtures(fly ash and mineral powder) after chlorine salt erosion were analyzed via scanning electron microscopy(SEM) and mercury injection porosimetry(MIP), providing the basis for the design and maintenance of concrete shafts in coal mines. The above-mentioned characteristics were compared with the macroscopic characteristic of concrete fractures under uniaxial compression. The results show that the macroscopic fracture characteristics of concrete under uniaxial compression change from longitudinal split fracture and oblique section shear fracture to conjugate cant fracture, and the degree of breakage *** cracks, cement paste cracks, spherical surface cracks, and aggregate cracks appear in concrete under uniaxial compression. In the early stages of corrosion, the original cracks which are obvious are repaired. When the corrosion becomes more serious, cement paste cracks appear, and the number of harmful holes increases while the number of harmless holes decreases. This study also reveals the relationship between the macroscopic properties and microscopic structure of concrete under chloride salt erosion. Finally, the paper preliminarily discussed the relationship between the macroscopic properties and mesoscopic characteristics of concrete under chlorine salt erosion.

关键词： Concrete Chlorine salt erosion Mesoscopic characteristic Damage fracture

On an isotropic porous solid cylinder:the analytical solution and sensitivity analysis of the pressure

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Applied Mathematics and Mechanics(English Edition) 2024年第9期45卷 1499-1522页

作者： H.ASGHARI L.MILLER R.PENTA J.MERODIO departamento de Matematica Aplicada a las TIC ETS de Ingenieria de Sistemas InformaticosUniversidad Politecnica de MadridMadrid 28031Spain School of Mathematics and Statistics University of GlasgowGlasgow G128QQU.K.

Within this work,we perform a sensitivity analysis to determine the influence of the material input parameters on the pressure in an isotropic porous solid *** provide a step-by-step guide to obtain the analytical solution for a porous isotropic elastic cylinder in terms of the pressure,stresses,and elastic *** obtain the solution by performing a Laplace transform on the governing equations,which are those of Biot's poroelasticity in cylindrical polar *** enforce radial boundary conditions and obtain the solution in the Laplace transformed domain before reverting back to the time *** sensitivity analysis is then carried out,considering only the derived pressure *** analysis finds that the time t,Biot's modulus M,and Poisson's ratio ν have the highest influence on the pressure whereas the initial value of pressure P_(0) plays a very little role.

关键词： sensitivity analysis Laplace transform cylindrical polar coordinate Biot's modulus cylinder

Unsuitable use of spin and pseudospin symmetries with a pseudoscalar Cornell potential

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Chinese Physics B 2014年第9期23卷 60-61页

作者： L.B.Castro A.S.de Castro departamento de Física CFM Universidade Federal de Santa Catarina departamento de Física Universidade Federal do Maranho Campus Universtitrio do Bacanga departamento de Física e Química Campus de Guaratinguet Universidade Estadual Paulista

The concepts of spin and pseudospin symmetries has been used as mere rhetorics to decorate the pseudoscalar potential [Chin. Phys. B 22 090301 （2013）]. It is also pointed out that a more complete analysis of the bou... 详细信息

关键词： Dirac equation pseudoscalar Comell potential spin symmetry pseudospin symmetry