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Comparative studies on Y(Ⅲ)and dy(Ⅲ)extraction from hydrochloric and nitric acids by Cyanex 572 as a novel extractant

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Journal of Rare Earths 2018年第12期36卷 1342-1350页

作者： N.E.El-Hefny m.S.Gasser Sh.Sh.Emam W.H.mahmoud H.F.Aly Hot Laboratories Centre Atomic Energy Authority Faculty of Science Ain Shams University

Extraction of Y(III) and dy(III) from hydrochloric and nitric acids by Cy-572 in kerosene was studied. The factors affecting the extraction were separately investigated. The stoichiometry of the extracted species was deduced on the basis of slope analysis method. Evaluation of extraction equilibrium and stripping investigation was studied as well as saponification effect of Cy-572. The composition of the extracted metal species in the organic phase was found to be [mA·(HA)] for Y(III) or dy(III) in both media.1.0 mol/L HCI is the best stripping agent for each metal ion from the studied acidic media in one *** Cy-572 does not exhibit any selectivity towards the extraction of Y(III) or dy(III) from both HCI and HNOsolutions. Based on the obtained results, the data were compared and the separation feasibility between lanthanides and Y(III) in the two media was discussed.

关键词： Extraction Cyanex-572 Yttrium Lanthanides Separation factor Saponification

Effect of self-weight consolidation on a hydro-sedimentological model for the Río de la Plata estuary

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International Journal of Sediment Research 2019年第5期34卷 444-454页

作者： Pablo Santoro mónica Fossati Pablo Tassi Nicolas Huybrechts Damien Pham Van Bang Ismael Piedra-Cueva Instituto de mecánica de los Fluidos e Ingeniería Ambiental Facultad de Ingeniería Universidad de la República Université Paris-Est Laboratory for Hydraulics Saint-Venant (ENPC-EDF/R& D-CEREMA) Electricity of France R&D Department Sorbonne Universités Université de Technologie de Compiègne FRE UTC-CNRS 3023 Roberval Centre de Recherche Royallieu Cerema Direction Technique Eau Mer et Fleuves Institut National de la Recherche Scientifique Centre-Eau Terre Environnement

The effect of the consolidation process on the morphodynamics and fine sediment dynamics of the Río de la Plata estuary is explored through a circulation-wave-sediment transport model. The consolidation model is calibrated based on settling column experimental data. Different simulations are done in order to initialize the mud layer distribution and to investigate the impact of different erosion parameter assumptions on the modeled sediment dynamics. Finally a two-year simulation is done with and without the consolidation process and realistic hydrodynamic forcings. Considering the consolidation process, the model correctly reproduces measured vertical density profiles in the montevideo Bay access channel. The simulated suspended sediment dynamics behavior in montevideo Bay with the consolidation process provides a more realistic deposition pattern in regard to the dredging activities.

关键词： Cohesive sediment Self-weight consolidation morphodynamics Numerical modeling

链球菌蛋白对人肝癌Bel-7402细胞的增殖抑制作用及其分子机制

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中国组织工程研究与临床康复 2007年第43期11卷 8733-8736页

作者：李彦芹郑群王艳李卫红朱俊平平国玲范东瀛张力平首都医科大学病原生物学系北京市100069 首都医科大学细胞生物学系北京市100069

目的:从分子水平观察链球菌蛋白质对人肝癌Bel-7402细胞的生长增殖的抑制作用。方法:实验于2005-10/2006-11在首都医科大学病原生物学系实验室完成。①链球菌32080株购自中国医学细菌保藏管理中心,人肝癌Bel-7402细胞株由首都医科大学... 详细信息

目的:从分子水平观察链球菌蛋白质对人肝癌Bel-7402细胞的生长增殖的抑制作用。方法:实验于2005-10/2006-11在首都医科大学病原生物学系实验室完成。①链球菌32080株购自中国医学细菌保藏管理中心,人肝癌Bel-7402细胞株由首都医科大学细胞生物学系惠赠。②常规培养链球菌并按照Winters方法提取细菌蛋白。③用0,10,20,100mg/L细菌蛋白作用于单层培养的Bel-7402细胞24,48,72h,采用mTT法检测链球菌蛋白对细胞的增殖抑制作用。④Bel-7402细胞经10mg/L或50mg/L细菌蛋白分别作用48,72h后,流式细胞术检测细菌蛋白对癌细胞生长周期时相分布。⑤Bel-7402细胞经50mg/L的细菌蛋白分别作用24,48,72h后,Annexin-v PI双染法检测Bel-7402细胞凋亡率。⑥用50mg/L的链球菌蛋白分别作用于Bel-7402细胞0,24,48,72h后,Western Blot检测链球菌蛋白对Bel-7402细胞凋亡相关蛋白的影响。结果:①链球菌蛋白对Bel-7402细胞的抑制作用:链球菌蛋白能显著抑制人肝癌Bel-7402细胞增殖,100mg/L细菌蛋白作用于细胞24,48,72h的抑制率分别为15.6%,35.6%,50%,呈剂量和时间依赖关系。②细菌蛋白对肝癌细胞生长周期时相分布及细胞凋亡率的影响:经链球菌蛋白(10,50mg/L)作用后,G2/m期Bel-7402细胞比率较正常对照组增加,差异有显著性(Pmg/L链球菌蛋白作用后,实验组Bel-7402细胞凋亡率明显高于对照组细胞(Pmg/L链球菌蛋白分别作用24,48,72h后,细胞色素C的释放逐渐增多,Procaspase-3及Bcl-2蛋白水平降低。结论:链球菌32080株蛋白对人肝癌Bel-7402细胞的生长抑制作用存在着剂量和时间依赖性,并能将细胞的生长周期阻滞于G2/m期,诱导细胞凋亡,影响Bcl-2,procaspase-3和细胞色素C等重要的凋亡相关蛋白水平。

关键词：链球菌细胞凋亡人肝癌Bel-7402细胞流式细胞术

Ambient noise H/V spectral ratio in site effects estimation in Fateh jang area, Pakistan

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Earthquake Science 2015年第1期28卷 87-95页

作者： S.m.Talha Qadri Bushra Nawaz S.H.Sajjad Riaz Ahmad Sheikh Department of Earth Sciences University of Sargodha College of Earth and Environmental Sciences University of the Punjab

Local geology or local site effect is a crucial component while conducting seismic risk assessment studies. Investigations made by utilization of ambient noise are an effective tool for local site estimation. The present study is conducted to perform site response analysis at 13 different sites within urban settlements of Fateh jang area （Pakistan）. The aim of this study was achieved by utilizing Nakamura method or H/V spectral ratio method. Some important local site parameters, e.g., the fundamental fre- quencies f0 of soft sediments, amplitudes A0 of corre- sponding H/V spectral ratios, and alluvium thicknesses over 13 sites within the study area, were measured and analyzed. The results show that the study area reflects low fundamental frequency fo. The fundamental frequencies of the sediments are highly variable and lie in a range of 0.6-13.0 Hz. Similarly, amplification factors at these sites are in the range of 2.0-4.0.

关键词： Local site effectspectral ratios Fundamentalfactor Alluvium thickness Ambient noise H/Vfrequency Amplification

microbial Activity Indices: Sensitive Soil Quality Indicators for Trace metal Stress

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Pedosphere 2005年第4期15卷 409-416页

作者： LI Yong-Tao T. BECQUER2 C. QUANTIN m. BENEDETTI P. LAVELLE DAI Jun College of Natural Resources and Environment South China Agricutrual University Guangzhou 510642 （China） UmR 137 Biodiversité et Fonctionnement des Sols Institut de Recherche Pour le Déueloppement （France） Université Paris Sud XI fre Orsay Terre 2566 Bat 504 91405 Cedex （France） UmR-CNRS 7047 Lab. de Géochimie et Métallogénie/Université Pierre et Marie Curie （France）

Physicochemical properties, total and DTPA （diethylenetriaminepentaacetic acid）-extractable Cu, Zn, Pb and Cd contents, microbial biomass carbon （C） content and the organic C mineralization rate of the soils in a long-term trace metal-contaminated paddy region of Guangdong, China were determined to assess the sensitivity of microbial indices to moderately metal-contaminated paddy soils. The mean contents of total Cu, Zn, Pb and Cd were 251, 250, 171, and 2.4 mg kg^-1 respectively. DTPA-extractable metals were correlated positively and significantly with total metals, CEC, and organic C （except for DTPA-extractable Cd）, while they were negatively and highly significantly correlated with pH, totall Fe and mn. metal stress resulted in relatively low ratios of microbial biomass C to organic C and in remarkable inhibition of the microbial metabolic quotient and C mineralization rate, which eventually led to increases in soil organic C and C/N. moreover, microbial respiratory activity showed a stronger correlation to DTPA-extractable metals than to total metal content. Likewise, in the acid paddy soils some “linked” microbial activity indices, such as metabolic quotient and ratios of basal respiration to organic C, especially during initial incubation, were found to be more sensitive indicators of soil trace metal contamination than microbial biomass C or basal respiration alone.

关键词： availability indication microbial characteristics trace metals

Band-gap engineering of La1-xNdxAlO3(x = 0,0.25,0.50,0.75,1)perovskite using density functional theory：A modified Becke Johnson potential study

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Chinese Physics B 2016年第6期25卷 376-382页

作者： Sandeep D P Rai A Shankar m P Ghimire Anup Pradhan Sakhya T P Sinha R Khenata S Bin Omran R K Thapa Department of Physics Mizoram University Aizawl-796004 India Department of Physics Pachhunga University College Aizawl-796001 India Department of Physics University of North Bengal Darjeeling-734013 India IFW Dresden e. V. P. O. Box 270116 D-01171 Dresden Germany Department of Physics Bose Institute 93/1 Acharya Prafulla Chandra Road Kolkata 700009 India Laboratoire de Physique Quantique et de modelisation mathematique (LPQ3m) Department de Technologie Universite de Mascara 29000 Mascara Algerie Algeria Department of Physics and Astronomy College of Science King Saud University P. O: Box 2455 Riyadh 11451 Saudi Arabia

The structural,electronic,and magnetic properties of the Nd-doped Rare earth aluminate,La1-xNdxAlO3（x = 0%to 100%） alloys are studied using the full potential linearized augmented plane wave（FP-LAPW） method within the density functional *** effects of the Nd substitution in La AlO3 are studied using the supercell *** computed electronic structure with the modified Becke–Johnson（m BJ） potential based approximation indicates that the La1-xNdxAlO3 alloys may possess half-metallic（Hm） behaviors when doped with Nd of a finite density of states at the Fermi level（EF）.The direct and indirect band gaps are studied each as a function of x which is the concentration of Nddoped La *** calculated magnetic moments in the La1-xNdxAlO3 alloys are found to arise mainly from the Nd-4f state.A probable half-metallic nature is suggested for each of these systems with supportive integral magnetic moments and highly spin-polarized electronic structures in these doped systems at *** observed decrease of the band gap with the increase in the concentration of Nd doping in La AlO3 is a suitable technique for harnessing useful spintronic and magnetic devices.

关键词： density functional theory rare earth aluminates perovskites electronic structures

Statistical modeling of total crash frequency at highway intersections

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Journal of Traffic and Transportation Engineering(English Edition) 2016年第2期3卷 166-171页

作者： Arash m.Roshandeh Bismark R.D.K.Agbelie Yongdoo Lee Department of Engineering and Public works City of AlpharettaGA 30009USA School of Civil Engineering Purdue UniversityWest LafayetteIN 47907USA Department of Civil and Environmental Engineering The Pennsylvania State UniversityUniversity ParkPA16802USA

Intersection-related crashes are associated with high proportion of accidents involving drivers, occupants, pedestrians, and cyclists. In general, the purpose of intersection safety analysis is to determine the impact of safety-related variables on pedestrians, cyclists and vehicles, so as to facilitate the design of effective and efficient countermeasure strategies to improve safety at intersections. This study investigates the effects of traffic, environ- mental, intersection geometric and pavement-related characteristics on total crash fre- quencies at intersections. A random-parameter Poisson model was used with crash data from 357 signalized intersections in Chicago from 2004 to 2010. The results indicate that out of the identified factors, evening peak period traffic volume, pavement condition, and unlighted intersections have the greatest effects on crash frequencies. Overall, the results seek to suggest that, in order to improve effective highway-related safety countermeasures at intersections, significant attention must be focused on ensuring that pavements are adequately maintained and intersections should be well lighted. It needs to be mentioned that, projects could be implemented at and around the study intersections during the study period （7 years）, which could affect the crash frequency over the time. This is an important variable which could be a part of the future studies to investigate the impacts of safety related works at intersections and their marginal effects on crash frequency at signalized intersections.

关键词： Total crash frequency Random-parameter count model Intersection Defected pavement

NIR emitting terephthalates(SmxdyyGd1-x-y)2(tph)3(H2O)4 for luminescence thermometry in the physiological range

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Journal of Rare Earths 2020年第5期38卷 492-497页

作者： Anastasia V.Orlova Vladislava Yu.Kozhevnikova Leonid S.Lepnev Alexander S.Goloveshkin Irina m.Le-Deigen Valentina V.Utochnikova m.V.Lomonosov moscow State University 1/3 Leninskye GoryMoscow119991Russian Federation P.N.Lebedev Physical Institute Leninsky prosp.531J9991MoscowRussian Federation A.N.Nesmeyanov Institute of Organoelement Compounds Russian Academy of SciencesVavilova St.28119991MoscowRussian Federation EVOLED Ltd. 1A-24 Puskina ielaRiga LV-1050Latvia

The first luminescence thermometer based on coordination compound of samarium and dysprosium is repo *** luminescence intensity and high signal resolution are reached thanks to the concentration quenching reduction due to the use of the trimetallic complexes of *** best thermometric properties in a wide temperature range among the studied systems are demonstrated by(Sm0.2dy0.15Gd0.65)2(tph)3(H2O)*** sensitivity reaches 0.5%/K in visible range and 1.2%/K in NIR range at low temperatures and 0.5%/K and 0.8%/K in physiological range.

关键词： Luminescence Lanthanides Carboxylates Thermometry NIR range Rare earths

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用于研究生物小分子碎裂的新装置(英文)

ImP & HIRFL Annual Report 2009年 197-197页

作者：李斌 R.Brédy S.martin Université Lyon 1 CNRSLASI M UMR557943 Bvd.Du.11 Novembre 1918F-69622 VilleurbanneFrance

In radiotherapy,the damage of DNA molecules is not only induced by direct impact of the primary high-energy particles,but also by low energy secondary species such as radicals,ions,and secondary electrons,etc.,generat...

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