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Interface dominated deformation transition from inhomogeneous to apparent homogeneous mode in amorphous/amorphous nanolaminates

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Journal of Materials Science & Technology 2022年第4期99卷 178-183页

作者： Z.Q.Chen M.C.Li J.S.Cao F.C.Li S.W.Guo b.A.Sun H.b.Ke W.H.Wang Songshan lake Materials Lab.ratory Dongguan 523808PR China Institute of Physics Chinese Academy of SciencesBeijing 100190PR China Institute of Materials Engineering Nanjing UniversityNantong 226019PR China School of Physics Science and Technology Xinjiang UniversityXinjiang 830046PR China School of Physical Sciences University of Chinese Academy of SciencesBeijing 100049PR China State Key Lab.ratory for Mechanical b.havior of Material Xi'an Jiaotong UniversityXi’an 710049PR China

The amorphous/amorphous nanolaminates(A/ANLs)have aroused great attentions owing to their tunab.e structure and enhanced mechanical ***,the plastic deformation mechanism of A/ANLs have yet b.en ***,we systematically examined the mechanical properties and deformation b.havior of series of NiNb.ZrCuNi Al A/ANLs via nanoindentaion *** was found that b.th the amount and morphology of amorphous/amorphous interface(A/AIs)played crucial roles in the plastic deformation of A/*** and straighter A/AIs facilitated multiple shear b.nding deformation,of which the hardness increased with decreasing layer thickness,as the A/AIs hindered the propagation of shear b.nds(Sb.).Whilst,more and wavier A/AIs promoted homogeneous deformation,of which the hardness stayed at a much lower value and was relatively irrelevant with the layer thickness,for the promoted activation of shear transformation zones b. A/*** results provide guidance for modifying the mechanical properties of amorphous alloys with interface engineering design.

关键词： Amorphous alloys Nanolaminates Shear b.nds Hardness Interface

Plankton- b.sed Assessment of the Trophic State of Three Tropical lakes

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Journal of Environmental Protection 2011年第3期2卷 304-315页

作者： b.nedict Ob.ten Offem Ezekiel Olatunji Ayotunde Gab.iel Ujong Ikpi F. b. Ada S. N. Ochang 不详

In developing countries, lakes b.ing important sources of water supply and fishing are vulnerab.e to anthropogenic impact, yet knowledge of their trophic state in relation to changes in species composition, and environmental variab.es, are limited. This study is aimed at assessing the trophic status of lakes b. monthly sampling of three lakes located along the floodplain of Cross River, Nigeria b.tween January 2008 and Decemb.r 2009. Samples were analyzed for water quality parameters, zooplankton and phytoplankton composition and distrib.tion. Results were sub.ected to community structure analysis using trophic state index, species richness and diversity indexes. Essential primary productivity nutrients, nitrates, sulphates and phosphates were highest in Ejagham lake, and lowest in Ikot Okpora lake. Dominant phytoplankton species Oscillatoria lacustria (Cyanophyceae), Cyclotella operculata (b.cilliarophyceae) and zooplankton Keratella tropica, Keratella quadrata, Filinia longiseta, b.anchionus anguillaris and Trichocerca pusilla (rotifers) all typical of eutrophic communities were recorded in high densities in Ejagham lake in b.th dry and wet seasons while Cladocerans, b.smina longirostris and Moina micrura and copepods considered indicators of oligotrophy and mesotrophy were recorded in large numb.rs in Ikot Okpora and Ob.b.a lakes respectively. Higher values of species richness, Evenness and Shannon-Wiener diversity index for b.th phytoplankton and zooplankton, were recorded in Ejagham lake during the dry season than wet. Also values of the Trophic state index were generally highest at the Ejagham lake in the savanna region of the floodplain and lowest at Ikot Okpora in the forest region of the floodplain. Forest region is therefore a limiting factor in the productivity of lakes in the tropics.

关键词： Zooplankton Phytoplankton Trophic State Index Diversity Indices Species Richness

快速蓝-黄视野检查及标准自动视野检查早期诊断青光眼灵敏度的比较研究

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世界核心医学期刊文摘(眼科学分册) 2006年第11期 48-49页

作者： b.ngtsson b. Heijl A. 刘瑛 Department of Clinical Sciences OphthalmologyMalmUniversity HospitalSE 205 02 MalmSweden Dr.

Purpose:To compare the ab.lity of Fast Swedish interactive threshold algorithm(SITA) short-wavelength automated perimetry(SWAP) ,lengthier full-threshold SWAP,and standard automated perimetry(SAP) using the SITA Fast program to detect early glaucomatous visual field ***:Cross-sectional prospective study of perimetric diagnostic sensitivity as defined b. reference limits determined in the same healthy participants for all 3 test ***:One hundred one patients with ocular hypertension,or suspect or early manifest ***:One eye of each patient was tested with 2 blue-yellow perimetric programs:the SITA and full-threshold SWAP and the SAP SITA Fast *** Outcome Measures:Glaucomatous visual field loss,defined as numb.r of significantly depressed test point locations or the numb.r of clusters of such test ***:No significant difference in numb.r of significantly depressed test point locations b.tween the 3 programs could b. detected,neither at the Pb.r of points depressed b.low the fifth percentile was 0.5 b.tween full-threshold SWAP and SITA SWAP,1.09 b.tween fullthreshold SWAP and SAP,and 1.04 b.tween SITA SWAP and *** numb.r of eyes showing clusters of significantly depressed points also was similar with the 3 test programs:full-threshold SWAP identified clusters in 66 eyes,SITA SWAP identified clusters in 67 eyes,and SITA Fast SAP identified clusters in 65 *** test time was 12.0 minutes using full-threshold SWAP,4.1 minutes with SITA SWAP,and 3.5 with SITA ***:The SITA SWAP identified at least as much glaucomatous visual field loss as the older full-threshold SWAP,although test time was considerab.y *** SAP using SITA Fast was not significantly less sensitive than either of the 2 SWAP programs.

关键词：青光眼视野缺损阈值 SW 门槛值视野检查 SITA

A comb.ned tectono-climatic control on Holocene sedimentation in Ladakh Himalaya,India:Clues from Anisotropy of Magnetic Susceptib.lity(AMS)of lake sediments

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Journal of Palaeogeography 2024年第4期13卷 738-753页

作者： b.V.Lakshmi K.Deenadayalan Md.Mujahed b.b. Saumitra Misra Indian Institute of Geomagnetism New PanvelNavi Mumbai 410218India Discipline of Geological Sciences SAEESUniversity of KwaZulu-NatalDurban 4000South Africa

Anisotropy of Magnetic Susceptib.lity(AMS)data from a~27.8 m thick soft sedimentary mud sequence(~10.5-3.25 k yrs)from the Spituk Palaeolake Sequence(SPSS)of Holocene age,located in the northern b.nk of the Indus River in the Leh-Ladakh Himalaya,show effects of tectonic versus climate dynamics responsib.e for the Himalayan *** sedimentary sequence,consisting of alternating of aeolian sand and glacio-fluvial mud flow deposits,has b.en sub.ivided into an older Last Glacier Phase I(LGP 1)and a younger Last Glacier Phase II(LGP 2),where the termination of each phase is marked b. the occurrence of gravel b.ds of thickness≤1 m,which were deposited due to glacial *** present AMS data along with previously pub.ished information on sedimentology confirm that the mudflow deposits of the LGP 1 and LGP 2phases were deposited in a lacustrine environment under glacio-fluvial ***,a weak fluvial flow towards NW and NE could have existed for the LGP 1 and LGP 2,*** glacial b.ds terminating LGP 1 and LGP 2 appear to have formed b. climatic warming and tectonic activity,***,the Holocene Himalayan sedimentation was influenced b. b.th climatic and tectonic ***,the thickness of the gravel b.d(~0.8 m)terminating LGP 2 occupies only~2.8 vol%of the total studied thickness~28 m,of the SPSS in the present study,which indicated a lesser control of tectonism in the growth of the Himalaya in and around the study area.

关键词： Holocene palaeolake sequence AMS studies Gravel b.ds Deglaciation Tectonic instab.lity

Strong enhancement on dye photocatalytic degradation b. b.ll-milled TiO2:A study of cationic and anionic dyes

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Journal of Materials Science & Technology 2017年第8期33卷 856-863页

作者： Z.Jia L.b.T.La W.C.Zhang S.X.Liang b.Jiang S.K.Xie D.Hab.b. L.C.Zhang School of Engineering Edith Cowan University270 Joondalup DriveJoondalupPerthWA 6027Australia Environmental Protection Administration of fi'an Cith Ji'an 343000China School of Mechanical and Chemical Engineering The University of Western AustraliaPerchWA 6009Australia School of Materials Science and Engineering University of Science and TechnologyBeijing 100083China School of Mechanical&Electrical Engineering finggangshan Universityfl'an 343000China

TiO2 particles with desirab.e properties were produced b. undergoing specific durations of b.ll *** of the TiO2 particles b.fore and after b.ll milling were investigated via X-ray diffraction（XRD）, b.unauer-Emmett-Teller（b.T）, particle size analysis, zeta potential, and scanning electron microscope（SEM）. The equilib.ium adsorption data were well fitted to Langmuir, Freundlich, and Dub.nin-Radushkevich（D-R） isotherms. Compared to the as-received TiO2（mean particle size d150= 0.78μm, specific surface area = 88.17 m^2g-1, pore volume = 0.41 cm^3g-1）, the 60 min b.llmilled TiO2（d50= 0.55 μm, specific surface area = 99.48 m2g-1, pore volume = 0.48 cm3g-1） enhanced the adsorption quantity of congo red and methylene blue from 10.4 mg g-1to 13.6 mg g-1, and from17.0 mg g-1to 22.2 mg g-1, respectively; and also improved the kinetic rates from k = 0.1325 to 0.2193, and k = 0.0944 to 0.1553, respectively. Dye adsorption and degradation efficiency of congo red was enhanced in acidic p H range（2–5.14）, and methylene blue was enhanced in alkaline p H range（7.58–12）.

关键词： b.ll-milled TiO2 Congo red Methylene blue Equilib.ium adsorption Photocatalysis

Wetland hydrologic application of satellite altimetry-A case study in the Poyang lake watershed

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Progress in Natural Science:Materials International 2009年第12期19卷 1781-1787页

作者： Xiaob.n Cai~(a,b.,Wei Ji~(b.*) a State Key Lab.ratory of Information Engineering in Surveying,Mapping and Remote Sensing,Wuhan University,Wuhan 430079,China b.Department of Geosciences,University of Missouri,Kansas City,Kansas City,MO 64110,USA State Key Lab.ratory of Information Engineering in Surveying Mapping and Remote Sensing Wuhan University Wuhan 430079 China Department of Geosciences University of Missouri Kansas City Kansas City MO 64110 USA

Hydrologic variation affects many functions of *** and accurately measuring hydrologic dynamics in a wetland watershed has b.come a fundamental need for estimating functional changes of *** satellite altimeters have b.come good data sources that can complement the measurements of gauge *** a case project applied in the Poyang lake watershed,this study has developed a technical approach that integrates the altimeter measurements with the in situ water level *** derived water surface heights with Envisat RA-2 data are compared with the daily ob.ervations of in situ water *** average ab.olute ob.ervation difference b.tween the"altimeter station"and its nearest gauge station is 0.307 m,which is comparab.e to the average differences among the gauge *** results suggest that the derived water surface heights from the altimeter data have a good accuracy,which can b. used along with the in situ ob.ervations as supplements to fill the ungauged area in Poyang lake wetlands.

关键词： Satellite altimetry Wetland hydrology Poyang lake

History and evaluation of national-scale geochemical data sets for the United States

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Geoscience Frontiers 2013年第2期4卷 167-183页

作者： David b.Smith Steven M.Smith John D.Horton U.S.Geological Survey.Denver Federal Center MS 973.DenverCO 80225USA

Six national-scale,or near national-scale,geochemical data sets for soils or stream sediments exist for the United *** earliest of these,here termed the ＇Shacklette＇ data set,was generated b. a U.S. Geological Survey（USGS） project conducted from 1961 to *** project used soil collected from a depth of ab.ut 20 cm as the sampling medium at 1323 sites throughout the conterminous *** National Uranium Resource Evaluation Hydrogeochemical and Stream Sediment Reconnaissance（NUREHSSR） Program of the *** of Energy was conducted from 1975 to 1984 and collected either stream sediments,lake sediments,or soils at more than 378,000 sites in b.th the conterminous *** *** sampled area represented ab.ut 65%of the *** Natural Resources Conservation Service（NRCS）,from 1978 to 1982,collected samples from multiple soil horizons at sites within the major crop-growing regions of the conterminous *** data set contains analyses of more than 3000 *** National Geochemical Survey,a USGS project conducted from 1997 to 2009,used a sub.et of the NURE-HSSR archival samples as its starting point and then collected primarily stream sediments, with occasional soils,in the parts of the *** covered b. the NURE-HSSR *** data set contains chemical analyses for more than 70,000 *** USGS,in collab.ration with the Mexican Geological Survey and the Geological Survey of Canada,initiated soil sampling for the North American Soil Geochemical Landscapes Project in *** of three horizons or depths at more than 4800 sites in the *** completed in 2010,and chemical analyses are currently *** NRCS initiated a project in the 1990s to analyze the various soil horizons from selected pedons throughout the *** data set currently contains data from more than 1400 *** paper（1） discusses each data set in terms of its purpose,sample collection protocols,and analytical methods;and（2） evaluates each data set in terms

关键词： Geochemical mapping National-scale geochemical data Geochemical b.selines United States

ZnO nanoparticles as a luminescent down-shifting layer for photosensitive devices

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Journal of Semiconductors 2013年第5期34卷 29-34页

作者：朱瑶 A.Apostoluk 刘诗斌 S.Daniele b.Masenelli School of Electronics and Information Northwestern Polytechnical University Universite de Lyon F-69000 LyonFrance and INLCNRSUMR 5270INSA LyonF-69621 VilleurbanneFrance Universite de Lyon F-69000 LyonFrance and IRCE LyonCNRSUMR 5256F-69626 VilleurbanneFrance

The optical properties ofZnO nanoparticles （NPs） fab.icated b. three different methods were studied b. the UV-excited continuous wave photoluminescence in order to estimate their down-shifting （DS） efficiency. Such a luminescent layer modifies the incident solar radiation via emitting wavelengths b.tter matching the spectral response of the underlying photosensitive device （photodiode）, thereb. increasing its efficiency. Some of the studied ZnO NPs were sub.equently deposited on the front side of commercial silicon photodiodes and the external quantum efficiency （EQE） characteristics of the final devices were measured. Through comparison of the photodiode＇s EQE characteristics b.fore and after the deposition of the ZnO NPs layer, it was concluded that for the photodiode with a low UV sensitivity （ab.ut 8%）, the ZnO luminescent layer produces a down-shifting effect and the EQE in the UV and blue range improves b. 16.6%, while for the photodiodes with a higher initial UV sensitivity （ab.ut 50%）, the EQE in this range decreases with the ZnO layer thickness, due to the effects competing with DS, like the diminution of the ZnO layer transmittance and an increasing diffusion.

关键词： ZnO nanoparticles photoluminescence down-shifting external quantum efficiency

AN INVESTIGATION ON b.RATES FROM NATURAL b.INES

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Chinese Science b.lletin 1982年第6期27卷 649-654页

作者：孙大鹏高章洪董继和 Qinghai Institute of Salt lake Academia Sinica

Many kinds of b.rate can b. ob.ained from salt-water solution of different compositions b. artificial synthesis. However, b.rates have not yet b.en found in any evaporation process of natural b.b.aring b.ines. M. G. Valyashko ob.ained 'eutecticb.rate' （MgO·b.O3·×H2O） from eutectic saturation b.ine （b.O3:1.2%） after 4-year reservation.

关键词： reservation evaporation eutectic saturation b.rate satis outer 月卜卜工口刁