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Chinese Physics B 2013年第3期22卷 117-121页

作者： e.Maghsoodi H.Hassanabadi S.Zarrinkamar Physics Department Shahrood University of TechnologyShahroodIran Department of Basic Sciences Garmsar BranchIslamic Azad UniversityGarmsarIran

exact analytical solutions of the Dirac equation are reported for the Poschl-Teller double-ring-shaped Coulomb *** radial,polar,and azimuthal parts of the Dirac equation are solved using the Nikiforov-Uvarov method,an... 详细信息

关键词： Dirac equation Poschl-Teller double-ring-shaped Coulomb potential Nikiforov-Uvarov method

Accuracy Assessment of Alos W3d30, Aster Gdem and Srtm30 Dem: A Case Study of Nigeria, West Africa

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Journal of Geographic Information System 2019年第2期11卷 111-123页

作者： O. I. Apeh v. N. Uzodinma e. S. ebinne e. C. Moka e. U. Onah Department of Geoinformatics & Surveying University of Nigeria Enugu Campus Nigeria

Digital elevation Models (DeMs) depict the configuration of the earth surface and are being applied in many areas in earth and environmental sciences. In this study, the accuracy of the Advanced Land Observing Satellite World 3D Digital Surface Model version 2.1 (ALOS W3D30), the Shuttle Radar Topography Mission Digital elevation Model version 3.0 (SRTM30) and the Advanced Space borne Thermal emission and Reflection Radiometer Global DeM version 2.0 (ASTeR GDeM2) was statistically assessed using high accuracy GPS survey data. Root-Mean-Square errors of ~5.40 m, ~7.47 m and ~20.03 m were obtained for ALOS W3D30, SRTM30 and ASTeR GDeM2 respectively. In further analyses, we discovered that ALOS W3D30 and SRTM30 were much more accurate in regions where the height intervals were within 201 m - 400 m and >801 m. ALOS W3D30 proved to be the most accurate DeM that best represents the topography of the earth’s surface and could be used for some earth and environmental applications in Nigeria. We recommend that this study should serve as a guide in the use of any of these DeMs for earth and environmental applications in Nigeria.

关键词： ALOS W3D30 ASTeR GDeM2 SRTM30 Nigeria DeMs Accuracy Assessment Root-Mean-Square error

Mode filtering based on ponderomotive force nonlinearity in a plasma filled rectangular waveguide

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Plasma Science and Technology 2017年第10期19卷 70-74页

作者： H SOBHANI H R SABOUHI S FeILI e DADAR Young Researchers and elite Club Qom Branch Islamic Azad University Department of electrical engineering Hormoz Branch Islamic Azad University Department of Physics Shahid Bahonar University Faculty of economic Mofid University

Here a new scheme for mode filtering is proposed. Based on the ponderomotive force effect,propagation of the microwave dual-mode through a plasma-filled metallic rectangular waveguide is investigated. To excite the Te_（20） mode in a rectangular waveguide, the existence of fundamental modes is unavoidable. To filter the destructive mode（Te_（10））, the waveguide is filled with a collisional plasma. Based on the coupling effect, the energy of this destructive Te_（10） mode is transferred to the Te_（20） mode. The proposed structure acts like a mode convertor. The Te_（10） mode become more attenuated and instead the Te_（20） mode is amplified. The plasma filled rectangular waveguide acts as a mode filtering tool.

关键词： mode filtering mode convertor collisional plasma ponderomotive force

安徽主要粮食作物天气指数保险模型研究与应用

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中国农业气象 2024年第5期45卷 562-570页

作者：杨太明曹雯高锷孙喜波许莹刘园沈光斌安徽省农村综合经济信息中心合肥230031 国元农业保险股份有限公司合肥230031 中国渔业互助保险社北京100080 中国农业科学院农业环境与可持续发展研究所北京100081

气象灾害是农业生产面临的主要风险之一,给农业安全生产带来巨大损失。农业保险是农业保障体系的重要组成部分,是有效分散农业风险或弥补灾害损失的重要救灾手段之一。20世纪90年代后期出现的天气指数保险,因其客观、标准化和流通性强... 详细信息

气象灾害是农业生产面临的主要风险之一,给农业安全生产带来巨大损失。农业保险是农业保障体系的重要组成部分,是有效分散农业风险或弥补灾害损失的重要救灾手段之一。20世纪90年代后期出现的天气指数保险,因其客观、标准化和流通性强等特点在全球引起广泛关注、研究与应用。本文在回顾了国内外天气指数保险技术的发展历程基础上,详细分析了天气指数保险与传统农业保险的差异,以及各自的优势与劣势;以安徽粮食作物(冬小麦、一季中稻、夏玉米)生长过程中特定农业气象灾害的天气指数保险为例,介绍天气指数模型研制与产品开发。通过天气指数农业保险产品在安徽多年实践应用,探索天气指数模型的改进方法,以降低基差风险;并对天气指数保险未来发展进行探讨与展望。

关键词：天气指数保险农业灾害风险评估气候变化

重度主动脉瓣狭窄伴冠状动脉中度狭窄病人新型CT指标测量研究

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国际医学放射学杂志 2024年第5期 623-624页

作者： M.C.Langenbach I.L.Langenbach B.Foldyna v.Mauri K.Klein S.Macherey-Meyer 苗彦许振华

目的冠状动脉疾病（CAD）常与严重主动脉瓣狭窄（AS）并存。经导管主动脉瓣置换术（TAvR）前行CT血管成像（CTA）虽可排除此类病人的CAD阻塞性病变，但对于

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Cosmology with an effective Λ-Term in Lyra Manifold

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Chinese Physics Letters 2013年第11期30卷 215-219页

作者： v.K.Shchigolev Department of Theoretical Physics Ulyanovsk State UniversityUlyanovsk 432000Russia

A cosmological model in Lyra's geometry is studied under the assumption that an effective cosmological term appears in the field equations as the result of interaction between the displacement vector field and an auxiliaryΛ*** exact solutions to the model equations are obtained and preliminarily studied for the simplest cases in order to illustrate how such a model works.

关键词： equations exact auxiliary

The Main Types of the Urals Mafic-Ultramafic Complexes

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Acta Geologica Sinica(english edition) 2016年第S1期90卷 239-240页

作者： SHMeLev v.R. Institute of Geology and Geochemistry

The mafic-ultramafic complexes and associated formationsare wide spread within the Ural folded belt,which is located on the boundary of the east european plate and West Siberian sedimentary *** main

关键词： The Main Types of the Urals Mafic-Ultramafic Complexes

Full-Annulus Simulation of the Surge Inception in a Transonic Centrifugal Compressor

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Journal of Thermal Science 2015年第5期24卷 442-451页

作者： I.Trébinjac e.Benichou N.Buffaz Laboratoire de Mécanique des Fluides et d’Acoustique UMR CNRS 5509 Ecole Centrale de Lyon UCBLyon I INSA 36 av. Guy de Collongue 69134 Ecully Cedex France Turbomeca groupe Safran 64511 Bordes France

Full annulus simulations of the flow which develops in a transonic centrifugal compressor are performed at two stable operating points （peak efficiency and near surge） and during the path to surge. At stable conditions, the flow field properties are analyzed by comparisons with experimental data and numerical simulations using a phase lagged approach previously carried out. Regarding the stage overall performance, an excellent agreement is obtained between the numerical results （both with time lagged approach and full-annulus calculation） and the ex- periments. From the full-annnlus simulations, the change in flow pattern from peak efficiency to surge is found to be perfectly similar to that obtained from the simulations using the time lagged approach. In particular, pro- vided that the operating point is stable, the flow proves to be chorochronic. The full-annulus simulations were continued after a unique small change in the throttle law applied at the exit of the numerical domain. The mass flow, pressure ratio and efficiency then significantly drop all the more the time progresses. The simulation becomes unstable and the surge inception well underway. The path to surge is found to be due to the enlargement of the boundary layer separation on the suction side of the diffuser vanes in accordance with the conclusions drawn from the chorochronic simulations and experiments. But as the time progresses, the flow loses its chorochronic character. Stall cells rotating at around 7% of the rotor speed develop and lead to surge in around 5 revolutions.

关键词： centrifugal compressor surge transonic rotating stall full-annulus simulation URANS

Sortilins in the blood-brain barrier:impact on barrier integrity

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Neural Regeneration Research 2023年第3期18卷 549-550页

作者： Andrea e.Toth Morten S.Nielsen Department of Biomedicine Faculty of HealthAarhus UniversityAarhusDenmark

Sortilin was discovered in 1997 by Petersen and his *** single transmembrane receptor was isolated as a 95 kDa membrane glycoprotein by receptor-associated protein affinity chromatography and therefore initially named *** cDNA library screening revealed sequence homology between the luminal segment of gp95/sortilin and the yeast vacuolar sorting protein 10 protein(vps10p)domain(Petersen et al.,1997).The vps10p domain was first identified in the Saccharomyces cerevisiae protein vps10p that directs lysosomal enzymes from the Golgi to the vacuole(Marcusson et al.,1994).

关键词： al. Petersen Sortilin

Fluoride removal by Al,Ti,and Fe hydroxides and coexisting ion effect

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Journal of environmental Sciences 2017年第7期29卷 190-195页

作者： Jianfeng Zhang Timothy e.Brutus Jiemin Cheng Xiaoguang Meng School of environmental and Municipal engineering Xi'an University of Architecture and TechnologyXi'an 710055China Center for environmental Systems Stevens Institute of TechnologyHobokenNJ 07030USA College of Geography and environment Shandong Normal UniversityJinan 250014China

Batch experiments were conducted to evaluate fluoride removal by Al,Fe,and Ti-based coagulants and adsorbents,as well as the effects of coexisting ions and formation of aluminum–fluoride complexes on fluoride removal by co-precipitation with alum（Al_2（SO_4）_3·18H_2O）.Aluminum sulfate was more efficient than the other coagulants for fluoride removal in the pH range between 6 and ***-crystalline TiO_2 was more effective for fluoride removal than Al and Fe hydroxides in a pH range of 3–*** anions in water decreased the removal of fluoride in the order：phosphate（2.5 mg/L）〉 arsenate（0.1 mg/L）〉 bicarbonate（200 mg/L）〉sulfate（100 mg/L） = nitrate（100 mg/L）〉 silicate（10 mg/L） at a pH of *** effect of silicate became more significant at pH 〉 *** and magnesium improved the removal of ***-potential measurements determined that the adsorption of fluoride shifted the PZC of Al（OH）_3 precipitates from 8.9 to 8.4,indicating the chemical adsorption of fluoride at the *** presence of fluoride in solution significantly increased the soluble aluminum concentration at pH 〈 6.5.A visual MINTeQ modeling study indicated that the increased aluminum solubility was caused by the formation of AlF^（2＋）,AlF^（＋2）,and AlF_*** AlF_x complexes decreased the removal of fluoride during co-precipitation with aluminum sulfate.

关键词： Fluoride removal Co-precipitation Aluminum sulfate Anion effect