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comparative Orotomy of the Archean Superior,North china,and Phanerozoic Altaid Orogenic Systems Architecture

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Acta Geologica Sinica(English Edition) 2024年第S01期98卷 33-35页

作者： T.m.KUSKY A.m.c.ŞENGÖr center for Global Tectonics School of Earth Sciences and State Key Laboratory for Geological Processes and Mineral ResourcesChina University of GeosciencesWuhan 430074China Eurasia Institute of Earth Sciences Istanbul Technical University34469IstanbulTürkiye Department of Geology Faculty of MinesIstanbul Technical University34469IstanbulTürkiye

Geological maps encode vast amounts of data about rock types,ages,chemistry,orogenic architecture and deep-time history or different tectonic units,yet these are often difficult to extract because of the way different geologists portray their results at various *** understand orogenesis in 4D,it is essential to uniformly integrate map data,together with geophysical data and deep geochemical mapping(Wang et al.,2023).

关键词： Archean comparative tectonics orotomy Superior craton Altaids North china craton

Effects of concurrent grain boundary and surface segregation on the final stage of sintering: the case of Lanthanum doped yttriastabilized zirconia

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journal of materials Science & Technology 2017年第3期33卷 251-260页

作者： m.m.Gong S.Dey L.j.Wu c.H.chang H.Li r.H.r.castro F.Liu State Key Laboratory of Solidification Processing Northwestern Polytechnical University Xi＇an 710072 China Department of materials Science ＆ Engineering University of California Davis CA 95616 USA

Dopants play a critical role in tailoring the microstructure during sintering of compacts. These dopants may form solid solution within the bulk, and/or segregate to the grain boundaries（GBs） and the solidvapor interfaces（free surfaces）, each causing a distinct energetic scenario governing mass transports during densification and grain growth. In this work, the forces controlling the dopant distribution, in particular the possibility of concurrent segregation at both surfaces and GBs, are discussed based on the respective enthalpy of segregation. An equation is derived based on the minimum Gibbs energy of the system to determine enthalpy of segregation from experimental interface energy data, and the results applied to depict the role of La as a dopant on the interface energetics of yttria stabilized zirconia during its final stage of sintering. It is shown that La substantially decreases both GB and surface energies（differently）as sintering progresses, dynamically affecting its driving forces, and consequent grain growth and densification in this stage.

关键词： Grain boundary(GB) segregation Surface segregation Enthalpy of segregation GB energy Surface energy

Potential contribution of combined Atmospheric ca^(2+) and mg^(2+) Wet Deposition Within the continental U.S. to Soil Inorganic carbon Sequestration

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Pedosphere 2013年第6期23卷 808-814页

作者： E.A.mIKHAILOVA m.A.GODDArD c.j.POST m.A.ScHLAUTmAN j.m.GALBrAITH School of Agricultural Forestand Environmental SciencesClemson University Department of Environmental Engineering and Earth Sciences Clemson University Department of crop and Soil Environmental Sciences Virginia Tech

Soil inorganic carbon （SIc） stocks continuously change from the formation of pedogenic carbonates, a process requiring inputs of ca2＋ and mg2＋ ions. This study ranked the soil orders in terms of potential inorganic carbon sequestration resulting from wet ca2＋ and mg2＋ deposition from 1994 to 2003 within the continental United States. The analysis revealed that average annual atmospheric wet deposition of ca2＋ and mg2＋ was the highest in the central midwest-Great Plains region, likely due to soil particle input from loess-derived soils. The soil orders receiving the highest total average annual atmospheric wet ca2＋ and mg2＋ deposition, expressed as potential inorganic carbon formation （barring losses from erosion and leaching）, were： 1） mollisols （1.1 × 10^8 kg c）, 2） Alfisols （8.4 × 10^7 kg c）, 3） Entisols （3.8 × 10^7 kg c）, and 4） Aridisols （2.8 × 10^7 kg c）. In terms of area-normalized result, the soil orders were ranked： 1） Histosols （73 kg c km-2）, 2） Alfisols and Vertisols （64 kg c km-2）, 3） mollisols （62 kg c km-2）, and 4） Spodosols （52 kg c kin-2）. The results of this study provide an estimate of potential soil inorganic carbon sequestration as a result of atmospheric wet ca2＋ and mg2＋ deposition, and this information may be useful in assessing dynamic nature of soil inorganic carbon pools.

关键词： calcite carbon cycle dolomite pedogenic

main α relaxation and slow β relaxation processes in a La30ce30Al15co25 metallic glass

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journal of materials Science & Technology 2019年第6期35卷 982-986页

作者： j.c. Qiao Y.H. chen r. casalini j.m. Pelletier Y. Yao School of mechanics Civil Engineering and Architecture Northwestern Polytechnical University Xi'an 710072 China chemistry Division Naval Research Laboratory Code 6120 Washington DC 20375-5342 United States Universite de Lyon MATEIS UMR CNRS5510 Bat. B. Pascal INSA-Lyon F-69621 Villeurbanne cedex France

Dynamic relaxation processes are fundamental to understand the mechanical and physical properties of metallic glasses. In the current work, mechanical relaxations in a La30ce30Al15co25 bulk metallic glass were probed by dynamic mechanical analysis. In contrast to many metallic glasses, La30ce30Al15co25 metallic glass shows a pronounced slow β relaxation peak. Physical aging below the glass transition temperature Tgleads to an increase of the apparent activation energy and a decrease of the slow β relaxation magnitude. The correlation between the slow β relaxation and the main α relaxation is discussed.

关键词： mechanical relaxation Dynamic mechanical relaxation α relaxation β relaxation Physical aging

Non-axisymmetric Homann stagnation-point flow of Walter’s B nanofluid over a cylindrical disk

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Applied mathematics and mechanics(English Edition) 2020年第5期41卷 725-740页

作者： m.KHAN m.SArFrAZ j.AHmED L.AHmAD c.FETEcAU Department of mathematics Quaid-i-Azam UniversityTaxila 47050Pakistan Department of Basic Sciences University of Engineering and TechnologySheringal Upper Dir 18000Pakistan Department of mathematics Shaheed Benazir Bhutto UniversitySheringal Upper Dir 18000Pakistan Academy of romanian Scientists Bucuresti 050094Romania

The study of non-axisymmetric Homann stagnation-point flow of Walter’s B nanofluid along with magnetohydrodynamic(mHD) and non-linear rosseland thermal radiation over a cylindrical disk in the existence of the time-independent free stream is considered. m.reover, the notable impacts of thermophoresis and Brownian motion are analyzed by Buongiorno’s model. The momentum, energy, and concentration equations are converted into the dimensionless coupled ordinary differential equations via similarity transformations, which are later num.rically solved by altering the values of the pertinent parameters. The num.rical and asymptotic solutions for the large shear-to-strain rate ratio γ =a/bfor the parameters of the displacement thicknesses and the wall-shear stress are computed by perturbative expansion and analyzed. Furtherm.re, the technique bvp4c in mATLAB is deployed as an efficient method to analyze the calculations for the non-dimensional velocities, temperature, displacement thickness, and concentration profiles. It is observed that the two-dimensional displacement thickness parameters α andβ are reduced due to the viscoelasticity and magnetic field effects. m.reover, when the shear-to-strain rate ratio approaches infinity, α is closer to its asymptotic value, while βand the three-dimensional displacement thickness parameter δ1 show the opposite *** outcomes of the viscoelasticity and the magnetic field on the skin friction are also determined. It is concluded that ■ reaches its asymptotic behavior when the shearto-strain rate ratio approaches infinity. meanwhile, ■ shows different results.

关键词： Walter’s B fluid cylindrical disk nanofluid magnetic field non-linear thermal radiation stagnation-point flow

Evolution of microstructure in semi-solid slurries of rheocast aluminum alloy

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Transactions of Nonferrous metals Society of china 2010年第9期20卷 1649-1655页

作者： r.cANYOOK S.PETSUT S.WISUTmETHA NGOON m.c.FLEmINGS j.WANNASIN Department of mining and materials Engineering Faculty of EngineeringPrince of Songkla University Department of mechanical Engineering Faculty of EngineeringPrince of Songkla University Department of materials Science and Engineering Massachusetts Institute of Technology

Semi-solid metal processing is being developed in die casting applications to give several cost benefits. To efficiently apply this em.rging technology, it is important to understand the evolution of microstructure in semi-solid slurries for the control of the theological behavior in semi-solid state. An experimental apparatus was developed which can capture the grain structure at different times at early stages to understand how the semi-solid structure evolves. In this technique, semi-solid slurry was produced by injecting fine gas bubbles into the melt through a graphite diffuser during solidification. Then, a copper quenching mold was used to draw some semi-solid slurry into a thin channel. The semi-solid slurry was then rapidly frozen in the channel giving the microstructure of the slurry at the desired time. Samples of semi-solid 356 aluminum alloy were taken at different gas injection times of 1, 5, 10, 15, 20, 30, 35, 40, and 45 s. Analysis of the microstructure suggests that the fragmentation by remelting mechanism should be responsible for the formation of globular structure in this rheocasting process.

关键词： microstructure evolution rheocasting rapid quenching method 356 aluminum alloy gas induced semi-solid (GISS) formation mechanism

Visualising data distributions with kernel density estimation and reduced chi-squared statistic

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Geoscience Frontiers 2017年第6期8卷 1247-1252页

作者： c.j.Spencer c.Yakymchuk m.Ghaznavi Earth Dynamics research Group The Institute of Geoscience ResearchDepartment of Applied GeologyCurtin UniversityPerthAustralia Department of Earth and Environmental Sciences University of WaterlooWaterlooCanada David r.cheriton School of computer Science University of WaterlooWaterlooCanada

The application of frequency distribution statistics to data provides objective means to assess the nature of the data distribution and viability of num.rical models that are used to visualize and interpret *** commonly used tools are the kernel density estimation and reduced chi-squared statistic used in combination with a weighted *** to the wide applicability of these tools,we present a java-based computer application called KDX to facilitate the visualization of data and the utilization of these num.rical tools.

关键词： Data visualisation Kernel density estimation reduced chi-squared statistic mean square weighted deviation Geostatistics

Soil Organic carbon Pools Under Switchgrass Grown as a Bioenergy crop compared to Other conventional crops

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Pedosphere 2013年第4期23卷 409-416页

作者： F.G.DOU F.m.HONS W.r.OcUmPAUGH j.c.rEAD m.A.HUSSEY j.P.mUIr Texas A&m AgriLife research &Extension center at Beaumont Department of Soil and crop Sciences Texas A&M University Texas A&m AgriLife research Station at Beeville Texas A&m AgriLife research and Extension center at Dallas Texas A&m AgriLife research and Extension center at Stephenville

Switchgrass （Panicum virgaturn L.） has been proposed as a sustainable bioenergy crop because of its high yield potential, adap- tation to m.rginal sites, and tolerance to water and nutrient limitations. A better understanding of the potential effects of biomass energy crop production practices on soil biological properties and organic matter dynamics is critical to its production. Our objective was to evaluate changes in c pools under a warm-season perennial switchgrass in different soils compared to typically-grown crops col- lected at college Station, Dallas, and Stephenville, TX in February 2001. Sampling depths were 0-5, 5-15, and 15-30 cm. Switchgrass increased soil organic c （SOc）, soil microbial biomass c （SmBc）, mineralizable c, and particulate organic matter c （POm-c） com- pared to conventional cropping systems. Soil c concentrations were in the order： long-term coastal bermudagrass [cynodon dactylon （L.） Pers.] 〉 switchgrass or kleingrass （Panicum coloratura L.） planted in 1992 〉 switchgrass 1997 〉 conventional cropping systems. Soil c concentrations tended to increase with increasing clay content. Greater microbial biomass c followed the order of Dallas 〉 college Station 〉 Stephenville, and ranged from approximately 180 mg c kg-1 soil at Stephenville to 1 900 mg c kg-1 soil at Dallas. Particulate organic c was m.re sensitive than other fractions to management, increasing as much as 6-fold under long-term coastal bermudagrass compared to conventional cropping systems. Our study indicated that conversion of conventional cropping systems into switchgrass production can sequestrate m.re SOc and im.rove soil biological properties in the southern USA.

关键词： cropping systems particulate organic c perennial grasses soil microbial biomass c soil mineralizable c

Structural effects induced by dialysis-based purification of carbon nanomaterials

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Nano materials Science 2024年第4期6卷 475-483页

作者： A.D.Veloso A.m.Ferraria A.m.Botelho do rego A.S.Viana A.j.S.Fernandes A.j.Fielding r.A.Videira m.c.Oliveira cQ-Vr and chemistry Department University of Tras-os-Montes e Alto Douro5000-801Vila RealPortugal BSIrG iBB-Institute for Bioengineering and BiosciencesDepartment of Chemical Engineeringand Associate Laboratory i4HB-Institute for Health and BioeconomyInstituto Superior TecnicoUniversidade de Lisboa1049-001LisbonPortugal centro de Química Estrutural Institute of Molecular SciencesDepartamento de Química e BioquímicaFaculdade de Ci^enciasUniversidade de LisboaCampo Grande1749-016LisboaPortugal I3N and Physics Department University of AveiroCampus de Santiago3810-193AveiroPortugal Faculty of Science Pharmacy and Biomolecular SchoolLiverpool John Moores UniversityUnited Kingdom rEQUImTE/LAQV Laboratorio de FarmacognosiaDepartamento de QuímicaFaculdade de FarmaciaUniversidade do Porto4050-313PortoPortugal

Dialysis plays a crucial role in the purification of nanomaterials but its impact on the structural properties of carbon nanomaterials was never ***,a carbon-based nanomaterial generated electrochemically in potassium phosphate buffer,was characterized before and after dialysis against pure *** is shown that dialysis affects the size of the carbon domains,structural organization,surface functionalization,oxidation degree of carbon,and grade of ***,dialysis drives the nanomaterial organization from discrete roundish carbon domains,with sizes ranging from 70 to 160 nm,towards linear stacking structures of small nanoparticles(m).In parallel,alcohol and ether(epoxide)surface groups evolve into m.re oxidized carbon groups(e.g.,ketone and ester groups).Investigation of the as-prepared nanomaterial by electron paramagnetic resonance(EPr)revealed a resonance signal consistent with carbon-oxygen centred ***,this study brings to light the selective affinity of the carbon nanomaterial under study to capture Na^(+)ions,a property greatly enhanced by the dialysis process,and its high ability to trap oxygen,particularly before *** findings open new perspectives for the application of carbon-based nanomaterials and raise awareness of the importance of structural changes that can occur during the purification of carbon-based nanomaterials.

关键词： Nanocarbon Surface functionalization Nmr XPS Hydrophilic carbon Paramagnetic