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material Research Related to Structural Pavement Failure on motorway A32 in the Netherlands

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武汉理工大学学报 2010年第17期32卷 8-17页

作者： houben l j m mOlENAAR A A A ERKENS S m j G Faculty Civil Engineering and Geosciences Delft University of Technology ministry of Traffic Public Works and Water ManagementCentre for Transport and Navigation

In 2008 structural failures occurred on the asphalt pavement,with a hydraulic blast furnace slag base,of the motorway A32 (constructed in 1986～1988) in the Netherlands. Within a few weeks serious depressions occurred,in which the asphalt pavement was full of cracks and the base had a very low stiffness. In 2008 and 2009 the pavement including the base was rehabilitated over a length of 10 *** Dutch ministry of Public Works has initiated an extensive research into the risks of occurrence of this type of unexpected structural damages on the main road network in the Netherlands. Among many other things this research includes material research into the base material of the A32 to find the cause of the structural *** total 130 cores,divided over 26 cross-sections,were drilled from the A32. The cross-sections were divided over 3 areas,with a high and low base stiffness respectively and also at heaves that had grown into the pavement since 1998. In areas with high base stiffness the cores mainly contained bound base material,in areas with low base stiffness mainly granular material and at the heaves it was a mix thereof. Standard (static) and dynamic crushing tests were done on the granular material. Dynamic and monotonic indirect tensile tests and compression tests were performed on the bound material. In all cases no systematic difference was found between the mechanical properties of the blast furnace slag base material from the heavily loaded right traffic lane and the material from the other *** is concluded that the pavement failure on the A32 is introduced by the occurrence of full depth asphalt fatigue cracks in the pavement that was originally designed for 12 years (but was never strengthened) in areas where the base stiffness always has been low or became low through crushing (that also has resulted in the heaves). Penetrated rainwater then has weakened the base and pumping has occurred,resulting into loss of bearing capacity and decrease of vo

关键词： structural failure blast furnace slags base laboratory testing

Emerging role of A-kinase anchoring protein 5 signaling in reward circuit function

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Neural Regeneration Research 2025年第10期20卷 2913-2914页

作者： William j.Flerlage mark l.Dell’Acqua Brian m.Cox Fereshteh S.Nugent Uniformed Services University of the Health Sciences Department of Pharmacology and Molecular TherapeuticsBethesdaMDUSA Department of Pharmacology University of Colorado School of MedicineAnschutz Medical CampusAuroraCOUSA

There is a strong evidence supporting the hypothesis of synaptic dysfunction as a major contributor to neural circuit and network disruption underlying emotional and mood dysregulation in psychiatric disorders(Simmons et al.,2024).Diverse sets of distinct molecular signaling pathways converge on the synapse to regulate synaptogenesis,synaptic function,and synaptic plasticity in brain regions and circuits through complex interactions organized by numerous multivalent protein scaffolds,including the family of proteins known as A-kinase anchoring proteins(AKAPs).

关键词： function supporting

Effect of periodic heat transfer on the transient thermal behavior of a convective-radiative fully wet porous moving trapezoidal fin

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Applied mathematics and mechanics(English Edition) 2023年第4期44卷 653-668页

作者： B.j.GIREESHA m.l.KEERTHI Department of PG Studies and Research in mathematics Kuvempu UniversityShankaraghatta 577451India

A moving trapezoidal profiled convective-radiative porous longitudinal fin wetted in a single-phase fluid is considered in the current *** periodic variation in the fin base temperature is taken into account along with the temperature sensitive thermal conductivity and convective heat transfer *** modeled problem,which is resolved into a non-linear partial differential equation(PDE),is made dimensionless and solved by employing the finite difference method(FDm).The results are displayed through graphs and *** effects of amplitude,frequency of oscillation,wet nature,Peclet number,and other relevant quantities on the distribution of temperature through the fin length and with the dimensionless time are *** is deciphered that the periodic heat transfer gives rise to the wavy nature of the fin thermal profile against *** analysis is beneficial in the design of fin structures for applications like solar collectors,space/airborne applications,and refrigeration industries.

关键词： convection fully wet porous fin trapezoidal profile moving fin unsteady periodic thermal condition

Design and Robust Performance Evaluation of a Fractional Order PID Controller Applied to a DC motor

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IEEE/CAA journal of Automatica Sinica 2017年第2期4卷 304-314页

作者： j.Viola l.Angel j.m.Sebastian Universidad Pontificia Bolivariana Universidad Politecnica de madrid Centre for Automation and Robotics (CAR) UPM-CSIC

This paper proposes a methodology for the quantitative robustness evaluation of PID controllers employed in a DC motor. The robustness analysis is performed employing a 2~3 factorial experimental design for a fractional order proportional integral and derivative controller(FOPID), integer order proportional integral and derivative controller(IOPID)and the Skogestad internal model control controller(SImC). The factors assumed in experiment are the presence of random noise,external disturbances in the system input and variable load. As output variables, the experimental design employs the system step response and the controller action. Practical implementation of FOPID and IOPID controllers uses the mATlAB stateflow toolbox and a NI data acquisition system. Results of the robustness analysis show that the FOPID controller has a better performance and robust stability against the experiment factors.

关键词： Factorial experimental design fractional-order PID controller robustness analysis SImC PID controller

A vacuum nano-casting route to magnetite cores/mesoporous silica shell composites

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Nano-micro letters 2009年第1期1卷 27-29页

作者： l.m.Guo j.l.Shi State Key laboratory of High Performance and Superfine microstructure Shanghai Institute of Ceramics Chinese Academy of Science

Hollow mesoporous silica spheres with magnetite cores(HmSmC) have been fabricated by Vacuum Nano-casting Route. The amount of magnetite cores and saturation magnetization value can be easily adjusted by changing the concentration of iron nitrate solution used in the synthesis procedure. Furthermore, the as-prepared HmSmCs still maintain narrow mesopore distribution, high surface area and large pore volume after the hollow cores of hollow mesoporous silica spheres were filled with magnetite particles. Specially, when the saturation magnetization value of as-prepared HmSmCs reaches 22.0 emu/g, the surface area and pore volume of corresponding HmSmCs are 149 m^2/g and 0.19 cm^3/g, respectively, and the pore size is 2.30 nm. The corresponding samples are characterized by X-ray diffraction, N_2 sorption isotherms, transmission electron microscopy and vibrating-sample magnetometer.

关键词： Hollow mesoporous silica spheres magnetite cores Vacuum nano-casting

Composition and evolution of the continental crust:Retrospect and prospect

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Geoscience Frontiers 2022年第5期13卷 1-15页

作者： j.l.R.Touret m.Santosh j.m.Huizenga Institut de minéralogie Physique des MatériauxCosmochimieSorbonne Universités4 Place JussieuF-75005 ParisFrance 121 Rue de la Réunion 75020 ParisFrance School of Earth Sciences and Resources China University of GeosciencesBeijing 100083China Department of Earth Science University of AdelaideAdelaideSA 5005Australia Faculty of Environmental Sciences and Natural Resource management Norwegian University of Life SciencesP.O.Box 5003NO-1432ÅsNorway EGRU(Economic Geology Research Centre) James Cook UniversityTownsvilleQueensland 4811Australia Department of Geology University of JohannesburgPO Box 524Auckland Park 2006South Africa

Until the middle of the 20th century,the continental crust was considered to be dominantly *** hypothesis was revised after the Second World War when several new studies led to the realization that the continental crust is dominantly made of metamorphic *** rocks were emplaced at peak metamorphic conditions in domains,which can be defined by geophysical *** to medium-grade metamorphic rocks constitute the upper crust,granitic migmatites and intrusive granites occur in the middle crust,and the lower crust,situated between the Conrad and moho discontinuities,comprises charnockites and *** continental crust acquired its final structure during metamorphic episodes associated with mantle upwelling,which mostly occurred in supercontinents prior to their disruption,during which the base of the crust experienced ultrahigh temperatures(>1000℃,ultrahigh temperature granulite-facies metamorphism).Heat is provided by underplating of mantle-derived mafic magmas,as well as by a massive influx of low H_(2)O activity mantle fluids,***-density CO_(2) and highsalinity *** fluids are initially stored in ultrahigh temperature domains,and subsequently infiltrate the lower crust,where they generate anhydrous granulite mineral *** brines can reach upper crustal levels,possibly even the surface,along major shear zones,where granitoids are generated through brine streaming in addition to those formed by dehydration melting in upper crustal levels.

关键词： Brines CO_(2) Continental crust Granulite lower crust

High-temperature granulites and supercontinents

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Geoscience Frontiers 2016年第1期7卷 101-113页

作者： j.l.R.Touret m.Santosh j.m.Huizenga Institut de mineralogie Physique des MateriauxCosmochimie(IMPMC)Sorbonne Universites et UPMC Univ Paris 06UMR CNRS 7590Museum National d'Histoire NaturelleIRD UMR 2064 Place JussieuF-FS005 ParisFrance School of the Earth Sciences and Resources China University of Geosciences(Beijing)29 Xueyuan RoadBeijing 100083China Economic Geology Research Institute(EGRU) College of ScienceTechnology and EngineeringJames Cook UniversityTownsvilleQueensland4811Australia Unit for Environmental Sciences and management North-West UniversityPrivate Bag X60012520South Africa

The formation of continents involves a combination of magmatic and metamorphic processes. These processes become indistinguishable at the crust-mantle interface, where the pressure-temperature（P-T）conditions of（ultra） high-temperature granulites and magmatic rocks are similar. Continents grow laterally, by magmatic activity above oceanic subduction zones（high-pressure metamorphic setting）, and vertically by accumulation of mantle-derived magmas at the base of the crust（high-temperature metamorphic setting）. Both events are separated from each other in time; the vertical accretion postdating lateral growth by several tens of millions of years. Fluid inclusion data indicate that during the high-temperature metamorphic episode the granulite lower crust is invaded by large amounts of low H2O-activity fluids including high-density CO2 and concentrated saline solutions（brines）. These fluids are expelled from the lower crust to higher crustal levels at the end of the high-grade metamorphic event. The final amalgamation of supercontinents corresponds to episodes of ultra-high temperature metamorphism involving large-scale accumulation of these low-water activity fluids in the lower *** accumulation causes tectonic instability, which together with the heat input from the subcontinental lithospheric mantle, leads to the disruption of supercontinents. Thus, the fragmentation of a supercontinent is already programmed at the time of its amalgamation.

关键词： Continents Supercontinents magmatism and metamorphism Fluids Tectonics

Chemically reactive and radiative von Kármán swirling flow due to a rotating disk

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Applied mathematics and mechanics(English Edition) 2018年第9期39卷 1295-1310页

作者： m.KHAN j.AHmED l.AHmAD Department of mathematics Quaid-i-Azam UniversityIslamabad 44000Pakistan Department of Basic Sciences University of Engineering and TechnologyTaxila 47050Pakistan Department of mathematics Shaheed Benazir Bhutto UniversitySheringal Upper Dir 18000Pakistan

A new mathematical model is presented to study the heat and mass transfer characteristics of magnetohydrodynamic(mHD) maxwell fluid flow over a convectively heated stretchable rotating disk. To regulate the fluid temperature at the surface, a simple isothermal model of homogeneous-heterogeneous reactions is employed. The impact of nonlinear thermal radiative heat flux on thermal transport features is studied. The transformed nonlinear system of ordinary differential equations is solved numerically with an efficient method, namely, the Runge-Kutta-Felberg fourth-order and fifth-order(RKF45)integration scheme using the mAPlE software. Achieved results are validated with previous studies in an excellent way. major outcomes reveal that the magnetic flux reduces the velocity components in the radial, angular, and axial directions, and enhances the fluid temperature. Also, the presence of radiative heat flux is to raise the temperature of fluid. Further, the strength of homogeneous-heterogeneous reactions is useful to diminish the concentration of reaction.

关键词： rotating stretchable disk magnetic field nonlinear radiative heat flux homogeneous-heterogeneous chemical reaction

Crystal Growth of[Ca3Al(OH)6·12H2O]2·(SO4)3·2H2O (Ettringite) Studied Under microgravity Conditions

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journal of Wuhan University of Technology(materials Science) 2020年第5期35卷 893-899页

作者： meier m R lEI l Rinkenburger A Plank j Technische Universitat miinchen Chair for Construction Chemistry85747 GarchingLichtenbergstrafie 4Germany

On parabolic flights,the growth of ettringite,[Ca3Al(OH)6·12H2O]2·(SO4)3·2H2O,a major reaction product of cement with water which forms instantaneously,was crystallized under microgravity conditions and *** the experiments,Ca(OH)2/Al2(SO4)3 solutions were combined and reacted for 10?s,followed by immediate filtration of the suspension and subsequent quenching with *** the ettringite crystals,the size,aspect ratios,quantity and morphology were determined and the results were compared with those from identical experiments performed under terrestric *** microgravity,generally smaller crystals (l-2.9 μm) precipitated in larger amount than under normal gravity (l-3.5 μm).The aspect ratios of the crystals grown under terrestric or microgravity condition were comparable at about *** is assumed that the reason for the smaller ettringite crystals is the absence of convection leading to more initial nuclei,but slower crystal growth which is diffusion ***,no preference relative to the ion transport to the different faces of the crystals *** results contribute to the understanding of the mineralization of inorganic salts under microgravity conditions for which hitherto only a handful of examples were reported.

关键词： crystallization ettringite microgravity morphology nucleation