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Determination of Element Levels of Lagoon from Townships near Cocody City Abidjan Côte D’Ivoire Using Energy Dispersive X-Ray Fluorescence 被引量:1
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作者 Alfred Djoman Djama Agbo Koudou Djagouri +1 位作者 Jean-Claude Olkalé Brigui Konin Pierre-Claver Kakou 《World Journal of Nuclear Science and Technology》 2021年第2期109-118,共10页
Eight water bottles from Ebrie lagoon with pollution potency were studied using nuclear chemistry technique and Energy dispersive X-ray fluorescence. This pollution is characterized by pH and conductivity parameters, ... Eight water bottles from Ebrie lagoon with pollution potency were studied using nuclear chemistry technique and Energy dispersive X-ray fluorescence. This pollution is characterized by pH and conductivity parameters, concentrations average in mg/L of metals such Fe (0.731), Mn (0.345), Cr (0.070), Cu (0.014) and concentrations of nutrients known to be pollutants and toxic for living or-ganisms. These heavy metals are dangerous to the lives, the local inhabitants and also a threat to aquatic life since this water is essential for the economical town, Abidjan. According to the Manganese concentration average (0.345 mg) values that higher than WHO (0.05 mg) value, the main likely source of pollu-tants is anthropogenic, industrial and agricultural. This study also shows the use of materials and lubricants near the lagoon that pollute this water. 展开更多
关键词 Ebrie Lagoon POLLUTION Heavy Metals energy dispersive X-Ray Fluorescence
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Alpha-actinin expression at different differentiating time points from temporal lobe cerebral cortex neural stem cells to neuron-like cells using energy dispersive X-ray analysis
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作者 Bo Yu Hua Li +3 位作者 Zhe Du Yang Hong Meng Sang Yuxiu Shi 《Neural Regeneration Research》 SCIE CAS CSCD 2009年第4期265-270,共6页
BACKGROUND: Alpha-actinin ( a -actinin) plays a key role in neuronal growth cone migration during directional differentiation from neural stem cells (NSCs) to neurons. OBJECTIVE: To detect in situ microdistribut... BACKGROUND: Alpha-actinin ( a -actinin) plays a key role in neuronal growth cone migration during directional differentiation from neural stem cells (NSCs) to neurons. OBJECTIVE: To detect in situ microdistribution and quantitative expression of a -actinin during directional differentiation of NSCs to neurons in the temporal lobe cerebral cortex of neonatal rats. DESIGN, TIME AND SETTING: Between January 2006 and December 2008, culture and directional differentiation of NSCs were performed at Department of Histology and Embryology, Preclinical Medical College, China Medical University. Immune electron microscopy was performed at Department of Histology and Embryology and Department of Electron Micrology, Preclinical Medical College, China Medical University. Spectrum analysis was performed at Laboratory of Electron Microscopy, Mental Research Institute, Chinese Academy of Sciences. MATERIALS: Basic fibroblast growth factor, epidermal growth factor, brain-derived nerve growth factor, type-1 insulin like growth factor, and a -actinin antibody were provided by Gibco BRL, USA; rabbit-anti-rat nestin monoclonal antibody, rabbit-anti-rat neuron specific enolase polyclonal antibody, and EDAX-9100 energy dispersive X-ray analysis were provided by PHILIPS Company, Netherlands. METHODS: NSCs, following primary and passage culture, were differentiated with serum culture medium (DMEM/F12 + 10% fetal bovine serum + 2 ng/mL brain-derived nerve growth factor + 2 ng/mL type-1 insulin like growth factor). MAIN OUTCOME MEASURES: Expression of a -actinin in neuron-like cells was quantitatively and qualitatively detected with immunocytochemistry using energy dispersive X-ray analysis. RESULTS: Immunocytochemistry, combined with electron microscopy, indicated that positive α -actinin expression was like a spheroid particle with high electron density. In addition, the expression was gradually concentrated from the nuclear edge to the cytoplasm and expanded into developing neurites, during differentiation of neural stem cells to neurons. Conversely, energy dispersive X-ray analysis indicated that the more mature the neural differentiation was, and the greater the expression of α -actinin. CONCLUSION: The gradual increase of α -actinin expression is related to growth, development, and maturity of differentiated neuron-like cells, in neonatal rat frontal lobe cortex, at different differentiating time points of NSCs to neurons. 展开更多
关键词 energy dispersive X-ray analysis a -actinin neural stem cells directional differentiation NEURONS
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Energy Dispersive X-Ray Spectroscopy of the Sohnari Member of Laki Formation from Southern Indus Basin of Pakistan
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作者 Muhammad Asif Noonari Surih Sibaghatullah Jagirani +5 位作者 Huafeng Tang Asghar A. A. D. Hakro Ali Ghulam Sahito Kaleemullah Jagirani Shahid Ali Shaikh Muhammad Dodo Jagirani 《Open Journal of Geology》 2021年第6期183-196,共14页
This study determines the geochemical and depositional environment analysis of the sediments of the Sohnari Member of the Laki Formation, Northern Kirthar Fold Belt of Pakistan. The Energy-Dispersive-X-Ray Spectroscop... This study determines the geochemical and depositional environment analysis of the sediments of the Sohnari Member of the Laki Formation, Northern Kirthar Fold Belt of Pakistan. The Energy-Dispersive-X-Ray Spectroscopy (EDS) technique is used for the detection of major elements and the effects of shifting depositional climatic conditions of six representative samples which were acquired from the Sohnari Member of the Laki Formation at Lakhra area, Sindh, Pakistan. The sedimentological studies clarify that the sediments the Sonahri Member are relatively immature and most migrated in clastic mode. The availability of Silica shows that the Member was formed due to biochemical precipitation and detrital mode and was deposited at a fast rate of sediment deposition under the fluvio-deltaic depositional system. This is also deduced that the rapid rate of sediment deposition might be created a reducing atmosphere and allowing for the mineralization of sulphur. 展开更多
关键词 energy dispersive X-Ray Spectroscopy GEOCHEMISTRY Sohnari Member the Laki Formation Northern Kirthar Fold Belt of Pakistan
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Energy-dispersive X-ray Spectroscopy for the Quantitative Analysis of Pyrite Thin Specimens
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作者 LUO Tingting GUO Yi +4 位作者 DENG Zhao LIU Xiaoqing SUN Zhenya QI Yanyuan YANG Meijun 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS CSCD 2023年第6期1304-1310,共7页
To explore ways to improve the accuracy of quantitative analysis of samples in the micrometer to nanometer range of magnitudes,we adopted analytical transmission electron microscopy(AEM/EDS)for qualitative and quantit... To explore ways to improve the accuracy of quantitative analysis of samples in the micrometer to nanometer range of magnitudes,we adopted analytical transmission electron microscopy(AEM/EDS)for qualitative and quantitative analysis of pyrite materials.Additionally,the k factor of pyrite is calculated experimentally.To develop an appropriate non-standard quantitative analysis model for pyrite materials,the experimentally calculated k factor is compared with that estimated from the non-standard quantitative analytical model of the instrument software.The experimental findings demonstrate that the EDS attached to a TEM can be employed for precise quantitative analysis of micro-and nanoscale regions of pyrite materials.Furthermore,it serves as a reference for improving the results of the EDS quantitative analysis of other sulfides. 展开更多
关键词 analytical transmission electron microscopy(AEM) energy dispersive X-ray spectroscopy(EDS) PYRITE thin specimen quantitative analysis
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Variations in Wave Energy and Amplitudes along the Energy Dispersion Paths of Nonstationary Barotropic Rossby Waves 被引量:2
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作者 Yaokun LI Jiping CHAO Yanyan KANG 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2021年第1期49-64,共16页
The variations in the wave energy and the amplitude along the energy dispersion paths of the barotropic Rossby waves in zonally symmetric basic flow are studied by solving the wave energy equation,which expresses that... The variations in the wave energy and the amplitude along the energy dispersion paths of the barotropic Rossby waves in zonally symmetric basic flow are studied by solving the wave energy equation,which expresses that the wave energy variability is determined by the divergence of the group velocity and the energy budget from the basic flow.The results suggest that both the wave energy and the amplitude of a leading wave increase significantly in the propagating region that is located south of the jet axis and enclosed by a southern critical line and a northern turning latitude.The leading wave gains the barotropic energy from the basic flow by eddy activities.The amplitude continuously climbs up a peak at the turning latitude due to increasing wave energy and enlarging horizontal scale(shrinking total wavenumber).Both the wave energy and the amplitude eventually decrease when the trailing wave continuously approaches southward to the critical line.The trailing wave decays and its energy is continuously absorbed by the basic flow.Furthermore,both the wave energy and the amplitude oscillate with a limited range in the propagating region that is located near the jet axis and enclosed by two turning latitudes.Both the leading and trailing waves neither develop nor decay significantly.The jet works as a waveguide to allow the waves to propagate a long distance. 展开更多
关键词 barotropic Rossby waves energy dispersion wave ray theory wave energy AMPLITUDE
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Variations in Amplitudes and Wave Energy along the Energy Dispersion Paths for Rossby Waves in the Quasigeostrophic Barotropic Model
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作者 Yaokun LI Jiping CHAO Yanyan KANG 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2022年第6期876-888,共13页
Variations in wave energy and amplitude for Rossby waves are investigated by solving the wave energy equation for the quasigeostrophic barotropic potential vorticity model.The results suggest that compared with rays i... Variations in wave energy and amplitude for Rossby waves are investigated by solving the wave energy equation for the quasigeostrophic barotropic potential vorticity model.The results suggest that compared with rays in the nondivergent barotropic model,rays in the divergent model can have enhanced meridional and zonal propagation,accompanied by a more dramatic variability in both wave energy and amplitude,which is caused by introducing the divergence effect of the free surface in the quasigeostrophic model.For rays propagating in a region enclosed by a turning latitude and a critical latitude,the wave energy approaches the maximum value inside the region,while the amplitude approaches the maximum at the turning latitude.Waves can develop when both the wave energy and amplitude increase.For rays propagating in a region enclosed by two turning latitudes,the wave energy approaches the minimum value at one turning latitude and the maximum value at the other latitude,while the total wavenumber approaches the maximum value inside the region.The resulting amplitude increases if the total wavenumber decreases or the wave energy increases more significantly and decreases if the total wavenumber increases or the wave energy decreases more significantly.The matched roles of the energy from the basic flow and the divergence of the group velocity contribute to the slightly oscillating wave energy,which causes a slightly oscillating amplitude as well as the slightly oscillating total wavenumber. 展开更多
关键词 Rossby waves quasigeostrophic barotropic model energy dispersion wave energy AMPLITUDE
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Three-dimensional Global Scale Permanent-wave Solutions of the Nonlinear Quasigeostrophic Potential Vorticity Equation and Energy Dispersion
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作者 H.L. Kuo (Department of Geophysical Sciences, University of Chicago, Chicago, IL 60637) 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 1995年第4期387-404,共18页
The three-dimensional nonlinear quasi-geostrophic potential vorticity equation is reduced to a linear form in the stream function in spherical coordinates for the permanent wave solutions consisting of zonal wavenumbe... The three-dimensional nonlinear quasi-geostrophic potential vorticity equation is reduced to a linear form in the stream function in spherical coordinates for the permanent wave solutions consisting of zonal wavenumbers from 0 to n and rn vertical components with a given degree n.This equation is solved by treating the coefficient of the Coriolis parameter square in the equation as the eigenvalue both for sinusoidal and hyperbolic variations in vertical direction. It is found that these solutions can represent the observed long term flow patterns at the surface and aloft over the globe closely. In addition, the sinusoidal vertical solutions with large eigenvalue G are trapped in low latitude,and the scales of these trapped modes are longer than 10 deg. lat. even for the top layer of the ocean and hence they are much larger than that given by the equatorial β-plane solutions.Therefore such baroclinic disturbances in the ocean can easily interact with those in the atmosphere.Solutions of the shallow water potential vorticity equation are treated in a similar manner but with the effective depth H=RT/g taken as limited within a small range for the atmosphere.The propagation of the flow energy of the wave packet consisting of more than one degree is found to be along the great circle around the globe both for barotropic and for baroclinic flows in the atmosphere. 展开更多
关键词 Finite amplitude potential vorticity solution General circulation Global scale energy dispersion
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Dispersion Energy in a Molecule Composed of Two Anisotropic Vibrating Dipoles
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作者 FAN Hong-Yi TANG Xu-Bing 《Communications in Theoretical Physics》 SCIE CAS CSCD 2006年第2X期209-212,共4页
For the first time, we derive the dispersion energy for a molecule which involves the anisotropic dipole interaction by virtue of the invariant eigen-operator method, which greatly simplifies the usual calculation if ... For the first time, we derive the dispersion energy for a molecule which involves the anisotropic dipole interaction by virtue of the invariant eigen-operator method, which greatly simplifies the usual calculation if one uses the Schroedinger equation. 展开更多
关键词 invariant eigen-operator dispersion energy anisotropic vibrating dipoles
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Tropical Cyclone Energy Dispersion and Possible Self- Maintenance Mechanism of the Synoptic- Scale Wave Trains
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作者 周霞琼 葛旭阳 《气象与环境科学》 2015年第1期14-25,共12页
The interaction between tropical cyclone(TC)and the large-scale mean flows such as the inter-tropical convergence zone(ITCZ)is investigated using a three-dimensional primitive equation model.Once a TC develops in the ... The interaction between tropical cyclone(TC)and the large-scale mean flows such as the inter-tropical convergence zone(ITCZ)is investigated using a three-dimensional primitive equation model.Once a TC develops in the vicinity of the ITCZ region where satisfies both barotropic and baroclinic instabilities,the southeastward energy dispersion from the TC may disturb the ITCZ and thus help its breakdown.Cumulus convection can be organized in the region of cyclonic circulation,and the interaction between convective heating and the perturbation circulation may enhance the development of the waves,leading to the generation of a new tropical cyclone to the east.While the TC moves to the high latitude,the ITCZ will reform.Though repeating of this process,a synoptic-scale wave train oriented in the northwest-southeast direction can be generated and self-maintained.The results suggest that the mutual interaction among the low-frequency background flow,wave train pattern and TCs provides a possible mechanism for the origin of the summer synoptic scale wave train pattern over the western North Pacific. 展开更多
关键词 tropical cyclone energy dispersion MECHANISM
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Gap States of ZnO Thin Films by New Methods:Optical Spectroscopy,Optical Conductivity and Optical Dispersion Energy
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作者 Vali Dalouji Shahram Solaymani +3 位作者 Laya Dejam Seyed Mohammad Elahi TSahar Rezaee Dariush Mehrparvar 《Chinese Physics Letters》 SCIE CAS CSCD 2018年第2期107-110,共4页
The optical reflectance and transmittance spectra in the wavelength range of 300-2500 nm are used to compute the absorption coefficient of zinc oxide films annealed at different post-annealing temperatures 400, 500 an... The optical reflectance and transmittance spectra in the wavelength range of 300-2500 nm are used to compute the absorption coefficient of zinc oxide films annealed at different post-annealing temperatures 400, 500 and 600°C.The values of the cross point between the curves of the real and imaginary parts of the optical conductivity ɑ_1 and ɑ_1 with energy axis of films exhibit values that correspond to optical gaps and are about 3.25-3.3 eV. The maxima of peaks in plots dR/dλ and dT/dλ versus wavelength of films exhibit optical gaps at about 3.12-3.25 eV.The values of the fundamental indirect band gap obtained from the Tauc model are at about 3.14-3.2 eV. It can be seen that films annealed at 600°C have the minimum indirect optical band gap at about 3.15 eV. The films annealed at 600°C have Urbach's energy minimum of 1.38 eV and hence have minimum disorder. The dispersion energy d of films annealed at 500°C has the minimum value of 43 eV. 展开更多
关键词 ZN Gap States of ZnO Thin Films by New Methods:Optical Spectroscopy Optical Conductivity and Optical Dispersion energy OC
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Frost Resistance of Pervious Concrete Mixed with Waste Glass Powder
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作者 AN Baofeng LI Qiong +4 位作者 QIAO Hongxia SU Rui WANG Xi WANG Chaoqun JIAO Daowei 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS CSCD 2024年第5期1325-1336,共12页
The contents of waste glass powder(WGP)(0%,10%,15%,20%,25%)and water-binder ratio(W/C)(0.24,0.26,0.28)were used as influencing factors,and the quality loss rate(Δm)and compressive strength loss rate(Δfc)were used as... The contents of waste glass powder(WGP)(0%,10%,15%,20%,25%)and water-binder ratio(W/C)(0.24,0.26,0.28)were used as influencing factors,and the quality loss rate(Δm)and compressive strength loss rate(Δfc)were used as characterization parameters.The Ca/Si ratio and main element contents of C-S-H gels with different WGP content were investigated by energy dispersive spectrometry(EDS).The pore structure evolution characteristics of WGP composite cementing materials were investigated by low field nuclear magnetic resonance(NMR).UsingΔfc as the index of frost resistance degradation and Weibull function,the frost resistance degradation of glass doped pervious concrete(WGP-PC)was modeled.The results show that,with WGP,for the same number of cycles,Δm andΔfc decrease and increase with the increase of WGP.Under the same WGP content,Δm andΔfc decrease first and then increase with the increase of W/C.After 100 freeze-thaw cycles,the samples with WGP content of 20%and W/C of 0.26 have the best freeze-resistance.Microscopic tests show that with the increase of WGP content,the Ca/Si ratio of C-S-H gel decreases at first and then increases with the increase of WGP content.The extreme value of Ca/Si is 2.36 when WGP is added by 20%.The pore volume of hardened paste with 20%WGP content decreased by 18.6%compared with that of cement system without WGP.The overall compactness of the specimen was improved.On the basis of the test data,a life prediction model was established according to Weibull function.The experiment showed thatΔfc could be used as a durability degradation index,and the slope of the reliability curve became gentle after WGP was added,which reduced the damage degradation rate of PC.W/C was 0.26.It's about 5000 hours. 展开更多
关键词 pervious concrete glass powder frost resistance energy dispersive analysis test low field nuclear magnetic resonance instrument life prediction
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Process mineralogy and characteristic associations of iron and phosphorus-based minerals on oolitic hematite 被引量:10
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作者 罗立群 张汉泉 《Journal of Central South University》 SCIE EI CAS CSCD 2017年第9期1959-1967,共9页
The chemical compositions,mineralogical characteristics,as well as dissemination of iron-and phosphorus-based minerals were studied for the E’xi oolitic hematite from western Hubei Province in China by using chemical... The chemical compositions,mineralogical characteristics,as well as dissemination of iron-and phosphorus-based minerals were studied for the E’xi oolitic hematite from western Hubei Province in China by using chemical analysis,optical microscope,electron probe micro-analyzer(EPMA)and energy dispersive spectroscopy(EDS).It is found that this kind of oolitic hematite ore contains 47.71%TFe,10.96%SiO_2,as well as 0.874%P,with hematite as the dominant Fe-bearing minerals,and quartz,chamosite,illite and cellophane as main gangue minerals.The microscope examination showed that the ore has an oolitic structure,with some ooids principally formed by a series of concentric layers of hematite collophanite around nucleus that is hematite in the association with collophanite.Based on the EPMA and EDS analysis,it can be known that some ooids are primarily composed of hematite and collophanite.The separation can be achieved through fine grinding for those collophanite laminae with a higher P content.However,the dissemination of two minerals at the interface will result in the difficulty in effective separation.Besides,some ooids are made of chamosite with some nucleus formed of quartz,which is principally finely disseminated with hematite.In view of the close association and dissemination of iron-and phosphorus-based minerals in the ooids,it is found that the process of stage-grindings and stage-separations can be adopted to effectively increase the iron recovery and decrease the P content in the concentrate to some extent. 展开更多
关键词 oolitic hematite process mineralogy dissemination of iron- and phosphorus-based minerals electron probe micro-analyzer(EPMA) energy dispersive spectroscopy (EDS)
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New approaches to characterizing urban air particles in central London 被引量:6
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作者 A.W.Mackay X.Long +1 位作者 N.L.Rose R.W.Battarbee 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 1999年第3期367-372,共6页
Atmospheric particles in central London during July 1996 have been apportioned to sources by two complimentary techniques: (1) morphological characteristics, determined using high power light microscopy; (2) chemical... Atmospheric particles in central London during July 1996 have been apportioned to sources by two complimentary techniques: (1) morphological characteristics, determined using high power light microscopy; (2) chemical composition determined by energy dispersive spectroscopy. During the study period, the majority of particles were found to be either biological in origin, or from vehicle related combustion processes. Trends in the latter group of particles are explored further. Numbers of particles per cubic metre were determined at an hourly resolution over a period of six days, and were found to be significantly correlated with other traffic pollutants such as benzene and 1,3 butadiene, although there is no relationship with mass of PM10 as measured by a nearby UK Government monitoring station. We suggest in this paper that numbers of particles from car exhausts are more representative of traffic pollution than current estimates which use monitoring by mass. 展开更多
关键词 urban air pollution PARTICULATES LONDON PM10s high power microscopy energy dispersive spectroscopy.
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Analysis of precipitation in a Cu-Cr-Zr alloy 被引量:5
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作者 Zhao Mei Lin Guobiao +1 位作者 wang Zidong Zhang Maokui 《China Foundry》 SCIE CAS 2008年第4期268-271,共4页
Precipites in Cu-0.42%Cr-0.21%Zr alloy were analyzed by using scanning electron microscope (SEM), energy dispersive X-ray spectroscopy (EDXS) and transmission electron microscope (TEM). After the solid solution ... Precipites in Cu-0.42%Cr-0.21%Zr alloy were analyzed by using scanning electron microscope (SEM), energy dispersive X-ray spectroscopy (EDXS) and transmission electron microscope (TEM). After the solid solution was performed at 980℃ for 2 h, water-quenched and aged at 450℃ for 20 h, the precipite had a bimodal distribution of precipitate size. The coarse precipitates are pure Cr and Cu5Zr, the dispersed fine precipitate is CrCu2(Zr, Mg) and pure Cr ranging from 1 to 50 nm. The coarse phases formed during solidification and were left undissolved during solid solution. The fine precipitates are the hardening precipitates that form due to decomposition of the supersaturated solid solution during aging. 展开更多
关键词 Cu-Cr-Zr alloy MICROSTRUCTURE precipite energy dispersive X-ray spectroscopy
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Rapid Biosynthesis of Silver Nanoparticles Using Cymbopogan Citratus (Lemongrass) and its Antimicrobial Activity 被引量:4
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作者 Shalaka A.Masurkar Pratik R.Chaudhari +1 位作者 Vrishali B.Shidore Suresh P.Kamble 《Nano-Micro Letters》 SCIE EI CAS 2011年第3期189-194,共6页
The present study deals with the rapid green synthesis of silver nanoparticles using fresh leaves of Cymbopogan Citratus(Lemongrass). Silver nanoparticles were formed within 8~10 minutes by microwave irradiation usin... The present study deals with the rapid green synthesis of silver nanoparticles using fresh leaves of Cymbopogan Citratus(Lemongrass). Silver nanoparticles were formed within 8~10 minutes by microwave irradiation using aqueous solution of Ag NO3(1 m M) with fresh leaves extract of Cymbopogan Citratus. The synthesized silver nanoparticles were characterized by using UV-visible spectrophotometer analysis, nanoparticle tracking analyzer, transmission electron microscope and energy dispersive X-ray spectra. The antibacterial activity of these nanoparticles was studied against multiple drug resistant hospital isolates of E.coli, S.aureus,P.mirabilis and hospital isolates of S. typhi, K.pnuemoniae. Also, the antifungal activity of these nanoparticles was studied against C.albicans(hospital isolate) and A.niger(NCIM 616). The synergistic effect of silver nanoparticles along with antibiotics was also studied against multiple drug resistant hospital isolates and found to be effective. The extracellular synthesis of Silver nanoparticles using leaves of Cymbopogan Citratus appears to be rapid and eco-friendly. 展开更多
关键词 Green synthesis Cymbopogan Citratus Nanoparticle tracking analyzer Transmission electron microscope energy dispersive X-ray spectra
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Mechanism of cement-stabilized soil polluted by magnesium sulfate 被引量:3
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作者 韩鹏举 王帅 +1 位作者 陈幼佳 白晓红 《Journal of Central South University》 SCIE EI CAS CSCD 2015年第5期1869-1877,共9页
In order to simulate and study the mechanism of cement stabilized soils polluted by different contents of magnesium sulfate(MS), a series of tests were conducted on the cemented soil samples, including unconfined comp... In order to simulate and study the mechanism of cement stabilized soils polluted by different contents of magnesium sulfate(MS), a series of tests were conducted on the cemented soil samples, including unconfined compression strength(UCS) tests of blocks, X-ray diffraction(XRD) phase analysis of powder samples, microstructure by scanning electronic microscopy(SEM),element composition by energy dispersive spectrometry(EDS), and pore distribution analysis by Image Processed Plus 6.0(IPP 6.0)software. The UCS test results show that UCS of cemented soils reaches the peak value when the MS content is 4.5 g/kg. While, the UCS for Sample MS4 having the MS content of 18.0 g/kg is the lowest among all tested samples. Based on the EDS analysis results,Sample MS4 has the greater contents for the three elements, oxygen(O), magnesium(Mg) and sulfur(S), than Sample MS1. From the XRD phase analysis, C-A-S-H(3Ca O·Al2O3·3Ca SO4·32H2O and 3Ca O·Al2O3·Ca SO4·18H2O), M-A-H(Mg O·Al2O3·H2O), M-S-H(Mg O·Si O2·H2O), Mg(OH)2 and Ca SO4 phase diffraction peaks are obviously intense due to the chemical action associated with the MS. The pore distribution analysis shows that the hydrated products change the distribution of cemented soil pores and the pores with average diameter(AD) of 2-50 μm play a key role in terms of the whole structure of cemented soil. The microscopic structure of the cemented soil with MS exhibits the intertwined and embedded characteristics between the cement and granular soils from the SEM images of cemented soils. The microstructure analysis shows that the magnesium sulfate acts as the additive, which is beneficial to the soil strength when the MS content is low(i.e., Sample MS2). However, higher MS amount involving a chemical action makes samples crystallize and expand, which is adverse to the UCS of cemented soils(i.e., Sample MS4). 展开更多
关键词 unconfined compression strength(UCS) magnesium sulphate(MS) X-ray diffraction(XRD) microstructure energy dispersive spectrometer(EDS)
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Determination of Water Diffusion Coefficients and Dynamics in Adhesive/Carbon Fiber Reinforced Epoxy Resin Composite Joints 被引量:3
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作者 WANG Chao WANG zhi +1 位作者 WANG Jing SU Tao 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2007年第4期474-478,共5页
To determinate the water diffusion coefficients and dynamics in adhesive/carben fiber reinforced epoxy resin composite joints, energy dispersive X-ray spectroscopy analysis(EDX) is used to establish the content chan... To determinate the water diffusion coefficients and dynamics in adhesive/carben fiber reinforced epoxy resin composite joints, energy dispersive X-ray spectroscopy analysis(EDX) is used to establish the content change of oxy- gen in the adhesive in adhesive/carbon fther reinforced epoxy resin composite joints. As water is made up of oxygen and hydrogen, the water diffusion coefficients and dynamics in adhesive/carben fiber reinforced epoxy resin composite joints can be obtained from the change in the content of oxygen in the adhesive during humidity aging, via EDX analy-sis. The authors have calculated the water diffusion coefficients and dynamics in the adhesive/carbon fiber reinforced epoxy resin composite joints with the aid of beth energy dispersive X-ray spectroscopy and elemental analysis. The de- termined results with EDX analysis are almost the same as those determined with elemental analysis and the results al- so show that the durability of the adhesive/carbon fther reinforced epoxy resin composite joints subjected to silane cou- pling agent treatment is better than those subjected to sand paper burnishing treatment and chemical oxidation treat- ment. 展开更多
关键词 Diffusion coefficient DYNAMICS energy dispersive X-ray spectroscopy Elemental analysis Adhesive/ carbon fiber reinforced epoxy resin composites joint
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Mechanism research on arsenic removal from arsenopyrite ore during a sintering process 被引量:2
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作者 Ri-jin Cheng Hong-wei Ni +2 位作者 Hua Zhang Xiao-kun Zhang Si-cheng Bai 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2017年第4期353-359,共7页
The mechanism of arsenic removal during a sintering process was investigated through experiments with a sintering pot and arsenic-bearing iron ore containing arsenopyrite; the corresponding chemical properties of the ... The mechanism of arsenic removal during a sintering process was investigated through experiments with a sintering pot and arsenic-bearing iron ore containing arsenopyrite; the corresponding chemical properties of the sinter were determined by inductively coupled plasma atomic emission spectrometry (ICP-AES), X-ray diffraction (XRD), and scanning electron microscopy (SEM) coupled with energy-dispersive X-ray spectroscopy (EDS). The experimental results revealed that the reaction of arsenic removal is mainly related to the oxygen atmosphere and temperature. During the sintering process, arsenic could be removed in the ignition layer, the sinter layer, and the combustion zone. A portion of FeAsS reacted with excess oxygen to generate FeAsO4, and the rest of the FeAsS reacted with oxygen to generate As2O3(g) and SO2(g). A portion of As2O3(g) mixed with Al2O3or CaO, which resulted in the formation of arsenates such as AlAsO4and Ca3(AsO4)2, leading to arsenic residues in sintering products. The FeAsS component in the blending ore was difficult to decompose in the preliminary heating zone, the dry zone, or the bottom layer because of the relatively low temperatures; however, As2O3(g) that originated from the high-temperature zone could react with metal oxides, resulting in the formation of arsenate residues. © 2017, University of Science and Technology Beijing and Springer-Verlag Berlin Heidelberg. 展开更多
关键词 ARSENIC Atmospheric temperature Atomic emission spectroscopy BLENDING energy dispersive spectroscopy Ignition Inductively coupled plasma Iron ore sinter Iron ores Mechanisms Oxygen Pollution control Scanning electron microscopy Sulfur dioxide X ray diffraction X ray spectroscopy
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Effect of Cu on Microstructures of Manganese Steel by EDXA and SEM 被引量:2
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作者 Xinhua CHEN Junhua DONG Enhou HAN Wei KE 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2007年第3期307-311,共5页
In order to investigate the distribution of Cu and Mg, and the effect of Cu on the microstructure of steels, manganese steels containing various Cu contents were annealed at 1260, 1100 and 1000℃, respectively, for I ... In order to investigate the distribution of Cu and Mg, and the effect of Cu on the microstructure of steels, manganese steels containing various Cu contents were annealed at 1260, 1100 and 1000℃, respectively, for I h and subsequently cooled to room temperature in the furnace to simulate the pre-rolling anneal. The results indicate that Cu is not microscopically segregated in the annealed steels. The scanning electron microscopy (SEM) observation shows that the main microstructure consist of ferrite and pearlite; the percentage of pearlite in the steels increases with increasing Cu content. The grain size reduces with the decrease of the annealing temperature. The results of energy dispersive X-ray analysis (EDXA) suggest that Cu content in pearlite is higher than that in ferrite, demonstrating that the microstructure-segregation of Cu occurred. However, the cast specimens show that Cu content in MnS and S-rich phases is high. In addition, Cu of 0.2%-0.4% could improve the distribution of MnS and S-rich inclusions. The optimal Cu content in steels and the optimal annealing temperature between 1100-1200℃ were determined. 展开更多
关键词 Manganese steels Copper-alloying ANNEALING energy dispersive X-ray analysis (EDXA) Scanning electron microscopy (SEM)
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Property changes of anchor grout calcined ginger nuts admixed with fly ash and quartz sand after accelerated ageing tests 被引量:2
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作者 ZHANG Jing-ke ZHANG Li-xiang +3 位作者 ZHAO Lin-yi LIU Dun GUO Qing-lin PEI Qiang-qiang 《Journal of Central South University》 SCIE EI CAS CSCD 2019年第11期3114-3125,共12页
Calcined ginger nuts admixed by fly ash and quartz sand (CGN-(F+S)) has been validated to be basically compatible to earthen sites as an anchor grout. Accelerated ageing tests including water stability test, temperatu... Calcined ginger nuts admixed by fly ash and quartz sand (CGN-(F+S)) has been validated to be basically compatible to earthen sites as an anchor grout. Accelerated ageing tests including water stability test, temperature and humidity cycling test, soundness test and alkali resistance test are conducted with the objective to further research the property changes of CGN-(F+S) grout. Density, surface hardness, water penetration capacity, water permeability capacity, soluble salt, scanning electron microscopy (SEM) images and energy dispersive spectrometry (EDS) spectrum of these samples have been tested after accelerated ageing tests. The results show that densities of samples decrease, surface hardness, water penetration capacity and water permeability capacity of samples increase generally. Besides, soluble salt analysis, SEM and EDS results well corroborate the changes. Based on the results it can be concluded that property changes are most serious after temperature and humidity cycling test, followed by water stability, soundness and alkali resistance test in sequence. But in general, CGN-(F+S) still has good durability. 展开更多
关键词 CGN-(F+S) grout accelerated ageing tests physical property change chemical property change scanning electron microscopy energy dispersive spectrometry
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