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挟沙水流引起底床冲淤变化的数值模拟

港工技术 2011年第1期48卷 5-9页

作者：谷汉斌李炎保 D.m.Causon 林鹏智曼彻斯特城市大学数学模型与流动分析中心交通运输部天津水运工程科学研究院天津300456 天津大学建筑工程学院港口工程系天津300072 四川大学水力学与山区河流开发保护国家重点实验室四川成都610065

本模型为垂向二维数学模型,以修正的NS方程为基础,采用粒子Level Set方法和对流扩散方程分别模拟自由水面和悬沙运动,根据底床物质质量平衡的原则计算底床变形,可模拟水流引起的底床冲淤变化。该模型将水流模型扩展到泥沙运动领域,以二... 详细信息

本模型为垂向二维数学模型,以修正的NS方程为基础,采用粒子Level Set方法和对流扩散方程分别模拟自由水面和悬沙运动,根据底床物质质量平衡的原则计算底床变形,可模拟水流引起的底床冲淤变化。该模型将水流模型扩展到泥沙运动领域,以二相流概念简化自由水面边界条件,模拟悬沙、底沙和底床变形;采用固定的笛卡尔坐标,不需重新划分计算网格,可方便地处理流体—泥沙—结构之间的相互作用;并以含沙水流穿越航道挖槽的落淤和在水流作用下管线基础局部冲刷为应用实例,验证其合理性。针对床面变形过程中可能出现泥沙坡面大于泥沙休止角,进而引发滑坡的情况,建议以虚拟时间法进行相应处理。

关键词：挟沙水流垂向二维数学模型悬沙底沙床面变形

Considerations about the occurrence of pollen grains of the Valeriana eichleriana (C. A. muller) Graebner, in sediments of the Upper Quaternary in the state of Rio Grande do Sul, Brazil

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Journal of Geoscientific Research in Northeast Asia 2004年第1期7卷 1-7页

作者： Paulo C.P.Neves Soraia G.Bauermann maria G.Rossoni Jose R.R.Coiro marleni m.Toigo Abdul R.Ashraf Laboratory of Palynology Lutheran University Canoas/RS CEP 92420-280 BrazilLaboratory of Palynology Lutheran University Canoas/RS CEP 92420-280 BrazilLaboratory of Palynology Lutheran University Canoas/RS CEP 92420-280 BrazilLaboratory of Microscopic Electronics Lutheran University Canoas/RS CEP 92420-280 BrazilInstitute of Geosciences Federal University of Rio Grande do Sul CEP 91501-970 BrazilInstitute of Geosciences University of Tuebingen Tuebingen D-72076 Germany

Valeriana eichle riana (C. A. muller) Graebner pollen are described and documented, used optical and scanning eletronic microscopy. We found that the current descriptions available goes this pollen disagree with the general pollinic pattern of the genera. Consequently, we conclude that the previous work in this area have taxonomical errors leading to inappropiate paleoenvironmental interpretations.

关键词： palynology Quaternary Valeriana

中度超重对原发性高血压患者血压昼夜模式、肾功能及钠水排泄的影响

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世界核心医学期刊文摘（心脏病学分册） 2005年第2期1卷 13-14页

作者： Bankir L. Sellin F. maillard m. 王亭忠 INSERm Unité367 Institut du Fer Moulin 17 rue du Fer M oulin 75005 Paris France Dr.

Obesity is a risk factor for arterial hypertension. We studied the relationshi ps between the body mass index(BmI) and the nycthemeral pattern of blood pressur e (BP), renal function and sodium and water excretion (EX) in a group of 25 mode rately hypertensive untreated men (41±2 y, 80±3 kg). Subjects were given a hig h sodium diet (6 g NaCl added to their usual diet, daily EX=200 mmol). On the 7t h day, BP was monitored during 24 h and urine collected in 2 fractions (day=D, 8 :00-22:00 and night=N, 22:00-8:00). Subjects were a posteriori divided into 2 groups according to th e median BmI (26 kg/m2): Group 1, n=12, BmI 23.2±0.6 (mean±SEm) and Group 2, n =13, BmI 29.2±0.5 kg/m2. No difference was observed between the two groups for age, 24 h urine and sodium EX, or systolic and diastolic BP. However, heart rate was significantly higher during N in Group 2 (66±2 vs. 57±2 b/min, p=0.012). Na and water EX were significantly higher during D than during N in Group 1, but lower during D than during N in Group 2. Creatinine clearance was higher in Gro up 2 than in Group 1 especially during N (D+29%, p=0.013; N+49%, pmore than in Group 1, as evaluated from the urine/plasma creatinine ratio (+49%, p=0.019). This ratio was positi vely correlated to BmI during D (r=0.561, p=0.004) but not during N. These resul ts show that the glomerular hyperfiltration associated with overweight is more i ntense at night and that moderately overweight hypertensives have a reduced sodi um and water EX during the day and a compensatory larger EX at night. The reduce d diurnal EX goes along with an increased urine concentration. The nocturnal ris e in EX is concomittant with a rise in heart rate. Given the growing health prob lems linked to obesity and hypertension, these results open a new field for the understanding of the difficulty to excrete sodium in this condition.

关键词：原发性高血压肾功能高盐饮食肌酐清除率常规饮食肾小球高滤过尿量血浆肌酐

The Song of the River

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山东师范大学外国语学院学报（基础英语教育） 2007年第1期9卷 98-98页

作者： m.S.maugham 范海祥

You hear it all along the *** hear it, loud and strong, from the rowers as they urge the junk with its high stern, the mast lashed alongside, down the swift running *** hear it from the trackers, a more breathless chant, as they pull desperately against the current, half a dozen of them perhaps if they are taking up wupan1, a couple of hundred if they are hauling a splendid junk, its square sail set, over a *** the junk, a man stands amidships beating a drum incessantly to guide their efforts, and they pull with all their strength, like men possessed, bent double; and sometimes in the extremity of their travail they crawl on the ground, on all fours, like the beasts of the *** strain, strain fiercely, against the pitiless might of the *** leader goes up and down the line and when he sees one who is not putting all his will into the task he brings down his split bamboo2 on the naked back. Each one must do his utmost or the labour of all is *** still they sing a vehement, eager chant, the chant of the turbulent waters.I do not know how words can describe what there is in it of *** serves to express the straining heart, the breaking muscles, and at the same time the indomitable spirit of man which overcomes the pitiless force of *** the rope may part and the great junk swing back, in the end the rapid will be passed; and at the close of the weary day there is the hearty meal...

关键词：大学英语阅读教学美文赏析英语教育师范院校

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灵丘硐沟银、锰矿床地质特征及成因

山西冶金 1999年第1期22卷 36-38页

作者：孟庆春马小兵冶金部第三地质勘查局地质勘查研究院

硐沟银锰矿床产于长城系高于庄组构造破碎带中,矿床规模中等,主矿体锰平均品位21.54％、银平均品位71.48g/t,是华北唯一优质银锰矿区。作者认为该矿床成矿作用经历了矿源层形成和燕山期成矿两个过程,属中低温热液矿床。

关键词：银、锰矿床地质特征硐沟

Application of Anodic Oxidation with Graphite Electrodes in Pretreated Leachates

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Open Journal of Applied Sciences 2020年第3期10卷 69-77页

作者： T.J.Sanchez-Sanchez H.A.Najera-Aguilar R.F.Gutierrez-Hernandez C.m.Garcia-Lara J.A.Araiza-Aguilar J.A.Bautista-Ramirez J.H.Castanon-Gonzalez Universidad de Ciencias y Artes de Chiapas Tuxtla GutierrezMexico Departmento de Ingenieria Quimica y Bioquimica Tecnologico Nacional de Mexico/IT de TapachulaTapachulaMexico Universidades para el Bienestar Benito Juarez Garcia Villa de AllendeEstado de MexicoMexico Department of Chemical and Biochemical Engineering Tecnologico Nacional de Mexico/IT de Tuxtla GutierrezTuxtla GutierrezMexico

Currently, landfills are the main method used for the final disposal of urban solid waste. The degradation processes that waste goes through in these sites, alongside rainwater that percolates through them, generate highly polluting liquids (leachate). In the treatment of leachate, advanced oxidation processes (AOP) can significantly reduce the concentrations of different pollutants. Due to the high documented potential around AOPs, in this study, the effectiveness of anodic oxidation in the removal of the remaining organic load in leachates pretreated in a biological system was evaluated. Graphite electrodes were used as anode and cathode. The efficiency of anodic oxidation, in terms of the removal of chemical oxygen demand (COD) and color, was evaluated under different current densities (7, 12, 17 and 22 mA/cm2) and pH values (3, 4.5 and 6). Under the best conditions found (22 mA/cm2 and pH of 6) and with an oxidation time of 5 hours, a maximum removal of 68% in COD and 91% in color was achieved, which represented a quality in the final effluent of 271 mg/L and 151 Pt-Co in COD and color, respectively. Therefore, considering that graphite is an economic and widely available material, the results obtained show anodic oxidation, with the use of graphite electrodes, as a technically viable alternative as a final purification stage for pretreated leachates.

关键词： Anodic Oxidation Graphite Electrodes Advanced Oxidation Processes

Experimental evidence of direct penetration of upstream ULF waves from the solar wind into the magnetosphere during the strong magnetic storm of November 9,2004

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Experimental evidence of direct penetration of upstream ULF ...

中国科学院地质与地球物理研究所第十届(2010年度)学术年会

作者： A.m.Du~(a,*),Wen-Yao Xu~a,W.Sun~b a Institute of Geology and Geophysics,Chinese Academy of Sciences,Beijing,China b Geophysical Institute,University of Alaska Fairbanks,AK,USA

Upstream ULF waves were recorded by the ACE satellite,while the Pc5 ULF waves(geomagnetic pulsations) were simultaneously observed by the goes12 satellite in the magnetosphere during the big magnetic storm on November 9,*** spectra showed similar structures with the maximum frequency band around 2.20-2.44 *** upstream ULF waves were highly correlated with the Pc5 waves with a correlation coefficient of 0.82 for a time lag of 28.5 *** the interplanetary and the magnetospheric waves had intense radial components with very large-amplitudeδB/B>40%,which indicated characteristic of the compressional ***,variations of the plasma density were in phase with those in the magnetic field,suggesting that they were essentially magnetosonic *** results demonstrated that upstream magnetosonic waves in the solar wind can directly penetrate into the magnetosphere and cause the Pc5 ULF waves during a big magnetic *** penetration of the magnetosonic waves seems to be occurred merely around the noon sector.

关键词： ULF waves Solar wind-magnetosphere coupling Interplanetary shock

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水电站入流预报之变换函数噪音模型

水电能源科学 1986年第4期 289-298页

作者：罗伯特m.汤姆普斯通基斯W.希伯 A.爱兰迈克牛得

本文研究魁伯克省亚尔堪熔炼化学制品有限公司电力系统的一些电站。对预测三小时流量和控制一个利用天然河川重力的发电厂进行了分析,并对自回归移动一般模型和变换函数噪音模型作了介绍,对最近在两类模型的模型结构识别、参数估算和诊... 详细信息

本文研究魁伯克省亚尔堪熔炼化学制品有限公司电力系统的一些电站。对预测三小时流量和控制一个利用天然河川重力的发电厂进行了分析,并对自回归移动一般模型和变换函数噪音模型作了介绍,对最近在两类模型的模型结构识别、参数估算和诊断检查阶段的进展也作了交代。

关键词： ARmA 变换函数噪音噪声语音

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Umbilical hernia

英国医学杂志中文版 2013年第5期16卷 318-318页

作者： L Barrelo A R Khan m Khabhai J L Brain

A healthy 2 vear old girl presented with an asymptomatic umbilical *** parents are concerned about the appearance and are worried that she will be teased when she goes to *** true umbilical hernia is a defect in the anterior abdominal wall underlying the umbilicus,through which the intestine can *** skin covered defect results from delayed contraction of the fibro muscular umbilical *** closure can occur up to the age of 4 or 5 years,depending on the size of the defect.

关键词：医学会诊临床诊断