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On the Fractal Mechanism of Interrelation Between the Genesis, Size and Composition of Atmospheric Particulate Matters in different Regions of the earth

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Atmospheric and Climate Sciences 2011年第3期1卷 120-133页

作者： Vitaliy d Rusov Radomir Ilic Radojko Jacimovic Vladimir N Pavlovich Yuriy A Bondarchuk Vladimir N. Vaschenko Tatiana N Zelentsova Margarita e Beglaryan elena P Linnik Vladimir P Smolyar Sergey I Kosenko Alla A Gudyma Odessa National Polytechnic University Shevchenko av. 1 65044 Odessa Ukraine

experimental data from the National Air Surveillance Network of Japan from 1974 to 1996 and from inde-pendent measurements performed simultaneously in the regions of Ljubljana (Slovenia), Odessa (Ukraine) and the Ukrainian “Academician Vernadsky” Antarctic station (64o15W;65o15S), where the air elemental composition was determined by the standard method of atmospheric particulate matter (PM) collection on nucleopore filters and subsequent neutron activation analysis, were analyzed. Comparative analysis of dif-ferent pairs of atmospheric PM element concentration data sets, measured in different regions of the earth, revealed a stable linear (on a logarithmic scale) correlation, showing a power law increase of every atmos-pheric PM element mass and simultaneously the cause of this increase – fractal nature of atmospheric PM genesis. Within the framework of multifractal geometry we show that the mass (volume) of atmospheric PM elemental components has a log normal distribution, which on a logarithmic scale with respect to the random variable (elemental component mass) is identical to normal distribution. This means that the parameters of two-dimensional normal distribution with respect to corresponding atmospheric PM-multifractal elemental components measured in different regions, are a priory connected by equations of direct and inverse linear regression, and the experimental manifestation of this fact is the linear correlation between the concentra-tions of the same elemental components in different sets of experimental atmospheric PM data.

关键词： Atmospheric aerosols Multifractal Neutron activation analysis South Pole Ukrainian Antarctic station

Lange Q&A Radiography examination

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2012年

作者： Saia, d.A.

ISBN: (纸本)9780071787215

1400+ Q&As and a test-simulating Cd deliver unmatched preparation for the radiography certification/recertification exam 4 STAR dOOdY'S ReVIeW! "This is an excellent resource for radiography student interns to use to prepare for the national registry. It poses a series of questions from each integral portion of radiography and covers all the units thoroughly...This is a wonderful resource for students to use to fully prepare for the exam...This is the best book around to prepare interns for the exam."--doody's Review Service LANGe Q&A: Radiography examination, 9e provides radiography students and recertifying radiographers with more than 1,400 registry-style questions with detailed answer explanations. Questions are organized by topic area for focused study and the book also includes two comprehensive practice *** ninth edition includes the ARRT examination content to be implemented in January 2012. Also new is coverage of computed tomography (CT) technology within the chapters on radiation protection, equipment, procedures, and CT imaging. Also included is an exam-simulating Cd containing two complete practice exams. Features Sections include Patient Care,Radiographic Procedures,Radiation Protection,Image Production and evaluation, andequipment Operation and Maintenance Written by an author with more than 35 years teaching experience each question includes detailed explanation of correct and incorrect answer options Companion Cd features one complete practice exam

关键词： Radiography Technology Radiologic examination Questions

来源：畅想之星图书光盘版（南... 评论

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喷头在风中性能的模拟

节水灌溉 1988年第1期 48-52页

作者： e.d伏里斯 R.d伏恩伯纳斯 R.H.米格耳森付元海河南省商丘地区水利局

灌溉系统的均匀度对于灌溉效率、农作物产量和经济效益都至关重要。而风对均匀度则具有强烈的影响。本文介绍了模拟喷灌系统在风中运行的方法。给出了描述水滴在空中运动的公式,使得从喷头喷出的水滴的运动轨迹可用数学方法计算出来。... 详细信息

灌溉系统的均匀度对于灌溉效率、农作物产量和经济效益都至关重要。而风对均匀度则具有强烈的影响。本文介绍了模拟喷灌系统在风中运行的方法。给出了描述水滴在空中运动的公式,使得从喷头喷出的水滴的运动轨迹可用数学方法计算出来。而根据各个计算结果就可预测喷水的图形。利用其喷洒水滴大小的组成来预测喷头周围的喷水图形。将这样水量分布图形进行叠加,其结果就代表一个非连续移动系统的灌水状态。然后即可计算出均匀系数,将预测的和实测的灌水图形进行比较,证实了模型的合理性。并对单喷头和多喷头的试验作了比较,这种模拟系统看来是预报在风中喷灌性能的有效工具。使用这类模型,可以改进喷头的设计。然而风向的变化会影响预报的精度。

关键词：摇臂式喷头水滴周围网格喷水初速度风速运动速度(体育) 喷灌系统克里斯琴森水流量雨筒

Palaeobiogeographical constraints on the distribution of foraminifers and rugose corals in the Carboniferous Tindouf Basin,South Morocco

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Journal of Palaeogeography 2013年第1期2卷 1-18页

作者： Ian d.Somerville Pedro Cózar Ismail Said daniel Vachard Paula Medina-Varea Sergio Rodríguez UCd School of Geological Sciences University College DublinBelfield dpto.de Geología Sedimentariay Cambio Ambiental Instituto de Geociencias (CSICUCM)c/José Antonio Novais28040-Madrid Spain dpto.de Paleontología Facultad de Ciencias Geológicas Universidad Complutense de Madridc/José Antonio Novais 228040-MadridSpain Université de Lille 1 UMR 8217 du CNRS:GéosystèmesBatiment SN 559655 Villeneuve d'Ascq France dpto.de Geología Sedimentariay Cambio Ambiental Instituto de Geociencias (CSICUCM)c/José Antonio Novais28040-MadridSpain dpto.de Paleontología Facultad de Ciencias GeológicasUniversidad Complutense de Madridc/José Antonio Novais 228040-MadridSpain

The northern flank of the Tindouf Syncline in southern Morocco exhibits a continuous, well exposed Carboniferous succession with limestones of Late Asbian to early Bashkirian age containing rich and diverse foraminiferal and rugose coral assemblages. Analysis of these assemblages provides new data on the relatively poorly known Saharan basins. The palaeobiogeographical relationship of the Tindouf Basin with other Palaeotethyan basins is complex. Although there is a predominance of cosmopolitan taxa for the Palaeotethys, it is recognized that there was an influence of basins from NW europe, such as the UK and Ireland. Some taxa are recorded in both NW europe and Tindouf without any characteristic contributions from intermediate basins in northern Morocco. The neighbouring Béchar Basin in Algeria presents distinct assemblages. The bulk of the data analyzed suggest that this sector of the western Palaeotethys can be subdivided into four palaeobiogeographical subprovinces: the Atlantic Subprovince (UK, Ireland, N France and Belgium), the Mediterranean Subprovince (Pyrenees, Montagne Noire, Betic Cordillera, Rif (N Morocco) and Balearic Islands), and the Saharan Subprovince (Béchar, Reggan, Ahnet-Mouydir and Tindouf). In between, mobile belts of mixed faunal assemblage characteristics are observed (e.g., SW Spain and Central Meseta) forming the West peri-Gondwanan *** of the Tindouf Basin faunas shows that, as in other Saharan basins, there is a high diversity and abundance of foraminiferal taxa, with a higher proportion of survivors and longer stratigraphic ranges; these features also are mirrored by rugose corals. This emphasizes the longevity of the carbonate platform in a tropical setting, where periodic transgressions introduced new assemblages, and oceanic currents are interpreted as one of the main controlling factors for the distribution of the taxa in these subprovinces. Moreover, not only were water temperatures on the platform higher, but also

关键词： Carboniferous palaeobiogeography new subprovinces foraminifers rugose corals Tindouf Basin North Africa

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涡流发生器对水翼流动分离的控制作用研究

工程热物理学报 2018年第1期39卷 92-97页

作者：车邦祥 Likhachev d S 曹琳琳邱宁初宁吴大转浙江大学化工机械研究所杭州310027

流动分离是引起水翼升阻比下降、诱发振动和噪声的重要原因。本文将涡流发生器应用于水翼,实验研究了涡流发生器对水翼上流动分离的抑制作用。通过在NACA0015翼型前缘设置一列微型涡流发生器,测试了不同来流速度下,水翼吸力面的压力分... 详细信息

流动分离是引起水翼升阻比下降、诱发振动和噪声的重要原因。本文将涡流发生器应用于水翼,实验研究了涡流发生器对水翼上流动分离的抑制作用。通过在NACA0015翼型前缘设置一列微型涡流发生器,测试了不同来流速度下,水翼吸力面的压力分布。实验结果发现,涡流发生器应用于水翼时,可增大近壁面流体动量,从而延迟甚至抑制流动分离的产生。类似于空气中作用,涡流发生器的高度对其控制流动分离的效果影响很大,当高度相对边界层厚度较小时,涡流发生器能较好地抑制流动分离。然而随着高度增加,对效果的影响却是非线性的,其原因还有待于进一步深入研究。

关键词：涡流发生器水翼流动分离流动控制实验研究

MeCHANISM OF SeCONdARY M_(23)C_6 PReCIPITATION AROUNd MC IN A COBALT-BASe SUPeRALLOY

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Acta Metallurgica Sinica(english Letters) 1999年第2期12卷 155-159页

作者： W.H. Jiang X.d. Yao H.R. Guan and Z.Q. Hu(1) department of Superalloys, Institute of Metal Research, The Chinese Academy of Sciences, Shenyang 110015, China2) department of Metal Materials engineering, Shenyang Polytechnic University) Shenyang 110023, Chi Inst of Metal Research the Chinese Acad of Sciences Shenyang China

Secondary M23C6 precipitation around primary MC carbide in a directionally solidified cobalt-base saperalloy was investigated duriny aging at 850℃. The results show that it was closely related to the decomposition of the MC. Two mechanisms were suggested,i.e. the in situ reaction, MC+γ→M23C6+C, and the direct reaction, M+C→M23C6,in which MC acted as a carbon source.

关键词： cobalt-base superalloy secondary precipitation carbide aging

Shielding AZ91d-1%Ca from corrosion through ultrasound melt treatment:A study for stent design

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Journal of Magnesium and Alloys 2023年第8期11卷 2901-2915页

作者： I.V.Gomes M.Pacheco M.Nienaber S.C.Neves d.Mei A.Barros R.L.Reis J.L.Alves H.Puga CMeMS–UMinho University of MinhoGuimarãesPortugal LABBeLS–Associate Laboratory BragaGuimarãesPortugal B's Research Group-Research Institute on Biomaterials Biodegradables and BiomimeticsUniversity of MinhoHeadquarters of the European Institute of Excellence on Tissue Engineering and Regenerative MedicineAvepark-Parque de Ciência e TecnologiaBarco GuimarãesPortugal ICVS/3B's-PT Government Associate Laboratory BragaGuimarãesPortugal Institute of Material and Process design Helmholtz-Zentrum HereonGeesthacht 21502Germany School of Materials Science and engineering&Henan Key Laboratory of Advanced Magnesium Alloy Zhengzhou UniversityZhengzhou 450001China

Magnesium-based materials show great potential for producing biodegradable stents,but their high corrosion rates are a *** study investigates whether ultrasound melt treatment can change the corrosion response of an extruded AZ91d-1.0%Ca(wt.%)in earle's Balanced Salt Solution by tailoring the intermetallics'morphology in the as-extruded *** results showed that the wires from ultrasound-treated ingots corroded faster than non-treated ones in immersion for up to 6 *** trend shifted for longer periods,and ultrasound-treated material showed lower corrosion rates and uniform corrosion,while the non-treated material displayed localized corrosion *** testing of the wires demonstrated that immersion in eBSS lowered the tensile strength and elongation at fracture due to material degradation,regardless of the processing ***,this decline was sharper in the non-treated *** findings suggest that ultrasound melt processing can be a promising method for improving the corrosion resistance of magnesium-based materials,paving the way for their use in manufacturing biodegradable stents.

关键词： Magnesium Ultrasound treatment Stent Corrosion Mechanical properties

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利用电磁波法监测流动流体

国外地质勘探技术 1984年第8期 17-22页

作者： R.J.Lytle d.L.Lager e.F.Lame J.d.Salysbury J.T.Okade. 王蕴华

前言当人们把流体泵入大地时,希望知道流体的速率(Attewel and Formex,1976)。例如,在油贮工程及关于化学废品贮藏的水文学研究中是重要的资料。目前这些测定受到均匀流速假设的限制。这个假设可能是错误的。譬如,一个共同的困难是可能... 详细信息

前言当人们把流体泵入大地时,希望知道流体的速率(Attewel and Formex,1976)。例如,在油贮工程及关于化学废品贮藏的水文学研究中是重要的资料。目前这些测定受到均匀流速假设的限制。这个假设可能是错误的。譬如,一个共同的困难是可能存在一个主要流动方向,或者流速可能与流体所占有的空间有关(参看

关键词：流体发射机电导率天然电子设备电性相位移

effects of Five Years Adoption of No-Tillage Systems for Vegetables Crops in Soil Organic Matter Contents

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Agricultural Sciences 2018年第1期9卷 117-128页

作者： Carlos e. P. Lima ítalo M. R. Guedes Juscimar da Silva Flávia A. Alcantara Nuno R. Madeira Agnaldo d. F. Carvalho Mariana R. Fontenelle embrapa Hortaliç as CNPH Brasília Brazil

Vegetables productions systems are done normally with intense soil tillage causing a strong decline of soil quality. Use of conservation systems can be an alternative to recover this quality. In order to evaluate the effects of such systems on soil organic matter, an experiment has been conducted in randomized blocks design and factorial scheme 3 × 2: three soil management systems (no-tillage;reduced tillage and conventional tillage) and two cover crops (maize single;and intercropping maize with gray velvet bean—Stizolobium niveum);and repeated measures over time. Soil samples were collected before the implementation of the experiment and at the end of each crop cycle until the fifth crop cycle. Carbon associated with humic substances is also determined in 0 - 5 cm, 5 - 10 cm and 10 - 30 cm at the end of the last crop cycle. The SOM content was higher in RT (48.34 g·kg-1) than in the CT (39.48 g·kg-1) at the end of the fifth crop cycle. SOM content in NT (44.92 g·kg-1) was statistically equal to RT and CT, during the same period. In 0 - 5 cm, carbon contents associated to the humic substances present the same behavior of SOM contents in 0 - 10 cm. Probably these results are associated with the capacity of each system to improve superficial contents of SOM stable fractions. It follows that the conservation systems used are alternatives to the cultivation vegetables in order to improve soil organic matter contents.

关键词： No-Tillage Reduced Tillage Soil Conservation Soil Management