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Simplified approach for design of raft foundations against fault *** i:free-field

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Earthquake Engineering and Engineering Vibration 2008年第2期7卷 147-163页

作者： i. Anastasopoulos N. Gerolymos G. Gazetas M. f. Bransb School of Civil Engineering National Technical University of AthensGreece Civil LecturerEngineeringUniversity of DundeeScotlandUK School of Civil Engineering National Technical University of AthensGreece Civil Engineering University of DundeeScotlandUK

Over the past few decades, earthquake engineering research mainly focused on the effects of strong seismic shaking. After the 1999 earthquakes in Turkey and Taiwan, and thanks to numerous cases where fault rupture caused substantial damage to structures, the importance of faulting-induced deformation has re-emerged. This paper, along with its companion （Part Ⅱ）, exploits parametric results of finite element analyses and centrifuge model testing in developing a four-step semi-analytical approach for analysis of dip-slip （normal and thrust） fault rupture propagation through sand, its emergence on the ground surface, and its interaction with raft foundations. The present paper （Part Ⅰ） focuses on the effects of faulting in the absence of a structure （i.e., in the free-field）. The semi-analytical approach comprises two-steps： the first deals with the rupture path and the estimation of the location of fault outcropping, and the second with the tectonically- induced displacement profile at the ground surface. in both cases, simple mechanical analogues are used to derive simplified semi-analytical expressions. Centrifuge model test data, in combination with parametric results from nonlinear finite element analyses, are utilized for model calibration. The derived semi-analytical expressions are shown to compare reasonably well with more rigorous experimental and theoretical data, thus providing a useful tool for a first estimation of near-fault seismic hazard.

关键词： fault rupture semi-analytical expression soil-structure interaction earthquake

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Study of Sintering Behaviour and Electrical Conductivity of Cr-Zn-fe-O System

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Journal of Materials Science & Technology 1999年第1期15卷 79-82页

作者： Hanna, A.A. Khalil, M.Sh. Saleh, H.i. Ali, A.f. inorganic Chemistry Department National Research Centre Dokki Cairo Egypt

A series of chemical composition based on Cr, fe and O with Zn as a partially substituting ion has been prepared in the general formula Zn//xCr//1// minus //xfe//2O by coprecipitation method using NH//4OH as the precipitating agent at pH equals 10.3. The prepared samples were identified by both thermal analysis (DTA and TGA) and X-ray diffraction. it was found that no single phase is obtained for any of the studied compositions but a mixture of different phases is observed, depending on the molar percentage of zinc ion substitution as well as on the sintering temperature. The temperature dependence of the electrical conductivity, sigma , of the prepared samples is plotted between 25 and 680 degree C. it was observed that the electrical conductivity increases with temperature for both samples with x equals 0.00 and 0.80 Zn ion content while it is nearly temperature independent for samples with intermediate Zn concentration x equals 0.2 and 0.5 mol fraction. The activation energy, E//a, calculated from the linear relation, lg sigma -1000/T for the final mixtures (sintered at 1300 degree C) was calculated. (Edited author abstract) 16 Refs.

关键词： Chromium compounds

Viscous flow simulations through *** progressive cavity pumps

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Petroleum Science 2020年第3期17卷 768-780页

作者： f.M.El-Abd E.M.Wahba i.G.Adam Mechanical Engineering Department Faculty of EngineeringAlexandria UniversityAlexandriaEgypt

Computational fluid dynamics(CfD)simulations of multi-lobe progressive cavity(PC)pumps are limited in the literature due to the geometric complexity of the pump,which places numerous restrictions on the grid generation *** present study attempts to alleviate such restrictions by developing a detailed numerical procedure for the numerical simulations of multi-lobe progressive cavity *** profile equations for the multi-lobe configuration at any section at each instant of rotation are presented.A structured grid generation method is developed to generate mesh files required for CfD simulations of multi-lobe PC *** from the present procedure are validated against single-lobe PC pump numerical results available in the ***,a numerical parametric study is carried out to investigate the effect of the number of lobes,the stator pitch,the circular fillet and clearance on the volumetric efficiency of PC pumps with viscous oils.

关键词： Progressive cavity pump Structured grid generation Computational fluid dynamics

Phase composition,conductivity,and sensor properties of cerium-doped indium oxide

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Nano Materials Science 2024年第2期6卷 193-200页

作者： M.i.ikim G.N.Gerasimov V.f.Gromov O.J.ilegbusi L.i.Trakhtenberg N.N.Semenov federal Research Center for Chemical Physics of RAS MoscowRussia University of Central florida OrlandoFLUSA Moscow institute of Physics and Technology(State University) DolgoprudnyMoscow RegionRussia Lomonosov Moscow State University MoscowRussia

The hydrothermal synthesis of in_(2)O_(3)and CeO_(2)–in_(2)O_(3)is investigated as well as the properties of sensor layers based on these *** the synthesis of in_(2)O_(3),intermediate products in(OH)_(3)and inOOH are formed,which are the precursors of stable cubic(c-in_(2)O_(3))and metastable rhombohedral(rh-in_(2)O_(3))phases,respectively.A transition from c-in_(2)O_(3)to rh-in_(2)O_(3)is observed with the addition of CeO_(2).The introduction of cerium into rh-in_(2)O_(3)results in a decrease in the sensor response to hydrogen,while it increases in composites based on c-in_(2)O_(3).The data on the sensor activity of the composites correlate with XPS results in which CeO_(2)causes a decrease in the concentrations of chemisorbed oxygen and oxygen vacancies in rh-in_(2)O_(3).The reverse situation is observed in composites based on c-in_(2)O_(3).Compared to in_(2)O_(3)and CeO_(2)–in_(2)O_(3)obtained by other methods,the synthesized composites demonstrate maximum response to H_(2)at low temperatures by 70–100℃,and have short response time(0.2–0.5 s),short recovery time(6–7 s),and long-term stability.A model is proposed for the dependence of sensitivity on the direction of electron transfer between in_(2)O_(3)and CeO_(2).

关键词： Cerium oxide indium oxide Nanocomposite Hydrothermal method Cubic phase Rhombohedral phase Sensor response Conductivity Hydrogen Response/recovery time

Transverse approach between real world concentrations of SO_2, NO_2, BTEX, aldehyde emissions and corrosion in the Grand Mare tunnel

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Journal of Environmental Sciences 2012年第7期24卷 1240-1250页

作者： i. Ameur-Bouddabbous J. Kasperek A. Barbier f. Harel B. Hannoyer GPM-UMR 6634 CNRS. UfR Science and Technology University of Rouen BP 12 76801 Saint Etienne du Rouvray Cedex France LCAE Chemistry Department Science Faculty of Tunis Campus Universitaire 2092 El Manar Tunis Tunisie DiRNO Rue de Verdun 76160 Darnetal France

With regard to automotive traffic, a tunnel-type semi enclosed atmosphere is characterized by a higher concentration of gaseous pollutants than on urban traffic roads and highlights the gaseous effluent species having an impact on material degradation. Therefore, a transverse approach between air quality and its consequences upon the longevity of materials is necessary, implying better knowledge of tunnel atmosphere and a better understanding of material degradation inside a tunnel for operating administration. Gaseous pollutant measurements carried out in a road tunnel in Rouen （Normandy） give the real world traffic concentrations of experimental exposure conditions. The sampling campaigns, achieved in summer and winter include SO2, NO2, BTEX and aldehyde analyses. Effluent profiles in the upward and downward tubes have been established. The current work shows that SO2, NO〉 formaldehyde, acetaldehyde, propanal and butanal must be considered in the degradation process of materials in a stuffy environment. As regards NO,, its concentration depends on the modification of the automotive fleet. The total aldehyde concentrations indicate no particular trend between the two bores. formaldehyde, acetaldehyde, propanal, butanal and acrolein species are the most abundant species emitted by vehicles and represent 90% to 95% of the total aldehyde emissions.

关键词： SO2 tunnel study aldehydes NO2 BTEX atmospheric corrosion

increasing the performance of anaerobic digestion:Pilot scale experimental study for thermal hydrolysis of mixed sludge

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frontiers of Environmental Science & Engineering 2010年第2期4卷 135-141页

作者： S.i.PEREZ-ELViRA M.fDZ-POLANCO f.fDZ-POLANCO Department of Chemical Engineering and Environmental Technology University of ValladolidValladolid 47011Spain

The performance of a pilot plant operation combining thermal hydrolysis(170℃,30 min)and anaerobic digestion(AD)was studied,determining the main properties for samples of fresh mixed sludge,hydrolyzed sludge,and digested sludge,in order to quantify the thermal pretreatment performance(disintegration,solubilisation,and dewaterability)and its impact on the anaerobic digestion performance(biodegradability,volatile solids reduction,and digester rheology)and end product characteristics(dewaterability,sanitation,organic and nitrogen content).The disintegration achieved during the thermal treatment enhances the sludge centrifugation,allowing a 70%higher total solids concentration in the feed to anaerobic *** digestion of this sludge generates 40%more biogas in half the time,due to the higher solids removal compared to a conventional *** waste generated can be dewatered by centrifugation to 7%dry solids without polymer addition,and is pathogen free.

关键词： anaerobic digestion(AD) biogas performance sludge thermal hydrolysis

Angular Differential Cross-Section for ionization of Helium in C^6＋ ion Collision

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Chinese Physics Letters 2004年第7期21卷 1258-1261页

作者： A.C.Gagyi-Palffy i.f.Barna L.Gulyas K.Tokesi DepartmentofTheoreticalPhysics UniversityofBucharestRomania Max-Planck-instituteforPhysicsofComplexSystems NothnitzerStr.38O1187DresdenGermany instituteofNuclearResearch HungarianAcademyofScience(ATOMKI)1-1-4001DebrecenPOBox51Hungary

With the help of the density operator, the angular differential cross-section for ionization of helium is calculated within the framework of the one-centre atomic-orbital close-coupling method. We consider a naked C6+ ion as projectile with an energy of 2.5MeV/a.u. Our result agrees well with the experimental data and the other theoretical calculations such as the first Born approximation, various Distorted Wave models and the classical trajectory Monte Carlo simulation.

关键词： Monte Carlo methods

Assessing the Sustainability of Underground Space Usage——A Toolkit for Testing Possible Urban futures

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Journal of Mountain Science 2011年第2期8卷 211-222页

作者： D.V.L.HUNT i.JEffERSON C.D.f.ROGERS The University of Birmingham

A description of the future as it might be without forecasts, predictions and trend analysis can be referred to as a 'future scenario'. An abundance of scenarios literature exists in which numerous pictures have been painted of changed future worlds. However, upon closer inspection it becomes apparent that virtually all of this literature refers to changes occurring above ground, ignoring the inevitable consequences (or opportunities) for sustainable use of underground space, not least in densely populated urban areas, some of which may be underlain by complex geological conditions. This paper reports on the development (to date) of an 'Urban futures' (Uf) toolkit for sub-surface environments (including infrastructure and utilities) which, through use of 'key' questions 'sustainable' indicators and a 'contextual' narrative, allows for better definition and measured performance of underground space in the UK, both today and in the future. The toolkit explores possible uses for underground space within 4 plausible and well-cited future scenarios (i.e. New Sustainability Paradigm, fortress World, Market forces and Policy Reform). This forms part of a much larger generic toolkit which the Uf research team are developing for exploring possible future scenarios over a range of UK urban regeneration case study areas.

关键词： urban futures toolkit underground space sustainability

Epistasis and Maternal Effect in Resistance to Puccinia coronata ***. avenae Eriks in Oats(Avena sp.)

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Agricultural Sciences in China 2010年第10期9卷 1462-1466页

作者： Bnejdi f Hammami i Allagui M B Saadoun M el Gazzah M Laboratoire de Génétique et Biométrie faculté des Sciences de Tunis Université Tunis institut National de la Recherche Agronomique de Tunisie(iNRAT) Rue Hadi Karray

The objective of this paper was to investigate the mode of heredity for resistance in oats （Avena sp.） to crown rust caused by Puccinia coronata Cda. f. sp. avenae Eriks, Eight generations of 2 crosses were used to estimate genetic effects and narrow-sense heritability （NSH）. Separate generation means analysis （GMA） indicated a complex gene action controlling this trait with additive, dominance, epistatic and maternal effects （ME）. The genetic model which assumed no epistasis and no ME did not accurately describe the resistance to P. coronata. in both crosses, the digenic epistatic model with ME was sufficient to explain variation in generation means for isolate CRec58 and isolate CRec46. Additive dominance and epistatic components were negative in most cases, suggesting that gene effects contributed more to the resistance than to the susceptibility. The estimated values of NSH were 15-99% depending upon the cross and isolates. The results indicated that appropriate choice of maternal parent and recurrent selection would increase resistance to crown rust in oats.

关键词： epistasis heritability maternal effect resistance