The Relationship between the Rise Width and the Full Width of-λ-ray Burst Pulses and Its Implications     

Rui-Jing Lu Yi-Ping Qin Ting-Feng Yi 《中国天文和天体物理学报》2006,6(1):52-60

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An analytical assessment on the impact of covers on the onset of air convection in mine wastes     

Ning Lu 《国际地质力学数值与分析法杂志》2001,25(4):347-364

If a mine waste pile is left open, an active chemical reaction of oxidation is often found due to the commonly high content of pyritic materials. The oxidation of pyrites is an exothermic process and the released heat will promote the flow of fresh oxygen from the surrounding atmosphere into the waste dump. As a result, oxidation reaction will accelerate and temperature within the dump can increase to as high as 60°C above the ambient temperature. The oxidation process also releases sulphuric acid and hydrogen ions into ground water to cause water contamination. Low‐permeability covers such as clay liners have been recently proposed to abate the oxidation process in mine wastes. The effectiveness of using low‐permeability materials to cover mine wastes in order to suppress the pyrite oxidation is examined. By conducting the theoretical analysis of the onset of convective air flow within waste rocks, the conditions under which soil gas flow is significant are identified. By comparing the results with previous field measurements and theoretical analysis for the uncovered conditions, it is shown that low‐permeability covers can effectively suppress soil gas flow and slow down the pyrite oxidation process in mine wastes. Copyright © 2001 John Wiley & Sons, Ltd.  相似文献   

Orbital Elements of 2004 Perseid Meteoroids Perturbed by Jupiter     

Josep Maria Trigo-Rodriguez  Jeremie Vaubaillon  José Luís Ortiz  Alberto Castro-Tirado  Jordi Llorca  Esko Lyytinen  Martin Jelínek  Antonio de Ugarte Postigo  Pablo Santos Sanz  Francisco J. Aceituno Castro  Albert Sánchez Caso  Antonio Bernal González  Juan Pastor Erades  Francisco Ocaña 《Earth, Moon, and Planets》2005,97(3-4):269-278

Jupiter and Saturn produce important gravitational impulses on meteoroids released by comet 109P/Swift-Tuttle. The meteoroids from this comet once released follow retrograde orbits that during their periodic approaches to these planets (within 1.6 and 0.9 A.U., respectively) are impulsed gaining orbital energy. This perturbation effect is translated into a net inward shift in the node of the perturbed meteoroids. Such geometry with Jupiter occurred in 2004 over a meteoroid trail ejected by this comet during the 1862 A.D. return of the comet to perihelion. In order to study the predicted outburst produced by one-revolution meteoroids, the Spanish Photographic Meteor Network (SPMN) performed an extensive campaign. As a part of this observational effort here are presented 10 accurate meteoroid orbits. We discuss their origin by comparing them with the theoretical orbital elements of the dust trails intercepting the Earth during the 2004 Perseid return.  相似文献   

AN OVERVIEW ON THE URBAN-RURAL INTERACTION IN THE PAST 50 YEARS IN CHINA   总被引：4，自引：0，他引：4  

LU Qi  ZHAN Jin-yan  LEE Kang-won 《中国地理科学(英文版)》2001,11(3):193-200

１ＩＮＴＲＯＤＵＣＴＩＯＮＢｙｄｅｆｉｎｉｔｉｏｎｕｒｂａｎｉｚａｔｉｏｎｉｓｔｈｅｐｒｏｃｅｓｓｏｆｒｕｒａｌａｒｅａｓｃｈａｎｇｉｎｇｉｎｔｏｕｒｂａｎａｒｅａｓｉｎｎａｔｕｒｅｆｏｒａｓｏｃｉ-ｅｔｙｉｔｉｓａｎａｔｕｒａｌｌｙｈｉｓｔｏｒｉｃａｌｐｒｏｃｅｓｓｏｆｔｈｅｔｒａｎｓｉｔｉｏｎｆｒｏｍａｔｒａｄｉｔｉｏｎａｌｒｕｒａｌｏｒａｇｒｉｃｕｌｔｕｒａｌｓｏｃｉｅｔｙｔｏａｍｏｄｅｒｎｉｚｅｄｕｒｂａｎｓｏｃｉｅｔｙＧＡＯ１９９１．Ｉｎｂｒｉｅｆｉｔｒｅｐｒｅｓｅｎｔｓａ…  相似文献   

南极长城站地区气象要素的中期振荡特征   总被引：2，自引：0，他引：2       下载免费PDF全文

陆龙骅  卞林根  张永萍 《极地研究》1989,1(4):12-20

本文用多维谱分析的方法研究了1985年1月-1987年12月南极长城站地面气象要素的谱特征。该地区的气象要素与北半球一样,也普遍存在3-5天、准一周、准二周和3-4周振荡周期。在长城站所在的乔治王岛地区,从地面到平流层中下部,气压系统都存在着显著的准二周振荡,这种振荡是由上往下传播的。无论冬、夏季,准二周和准一周振荡都是由西往东传播的,而扰动的南北传播方向则与季节及振荡周期长度有关。南极地区的中期振荡特征与500hPa极地涡旋的活动和强度变化有密切关系。  相似文献   

天鹅座X-1硬X射线的能量谱     

马宇蒨  李光华  张承模  钱跃民  肖谦益  陆柱国  吴枚  戴长江  李惕碚  顾逸东  张希元 《中国天文和天体物理学报》1989,(4)

1985年9月22日,我们用空间硬X射线望远镜HAPI-2,在我国的高空气球上,对天鹅座X-1进行了观测,望远镜几何面积为140cm~2,观测能区20—200keV,空间定向精度±0.2°。获得的硬X射线能谱陡,总辐射能流LX～1.0×1~(37)erg/sec,低于常规态。本文将介绍望远镜的性能和观测过程,能谱分析的结果,并对当时天鹅座X-1可能的“态”进行讨论。  相似文献   

中小地形对局地天气气候的影响     

Lu Jinghua Chen Gangyi 《成都信息工程学院学报》1989,(1)

本文采用地形活动坐标系,研究在二维运动条件下地形对局地天气气候的影响。指出:地形对气流的影响不仅与地形高度z有关,而且与地形的坡度α,下垫面的热力分布,近地层大气稳定度г,垂直交换系数k以及基流v等诸因素密切相关。其中下垫面温差,地形坡度和基流尤为重要。  相似文献   

A review on the Arctic research using CiteSpace          下载免费PDF全文

Wang Li  Yang Linsheng  Huang Jixia  Jinmei Lu 《极地研究》1988,31(3):346

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黄河下游泥沙输移数值模拟   总被引：2，自引：0，他引：2  

励强  徐小惠 《地理研究》1989,8(2):55-63

本文从数学模型入手,探讨黄河下游在多年平均来水来沙条件下,泥沙输移与泥沙淤积的特性,得出黄河下游泥沙沿程淤积分布不均匀主要是由于粗沙、中沙沿程淤积不均匀造成的,如果使来沙减少42.6%,黄河下游可望达到冲淤平衡.  相似文献   

21cm波段太阳爆发中的精细结构     

龚元芳  吕松泉  尚琼珍  胡汉明  施硕彪  李琼英 《中国天文和天体物理学报》1989,(1)

本文简要介绍了云南天文台新建立的21cm波段快速(不中断采样)记录系统,及使用该系统观测到的快速尖峰事件。系统得到的太阳分米波段爆发中不同时间尺度的精细结构与Stu-rroch等提出的太阳耀斑中能量释放的模式相一致。  相似文献