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721.
1936年灵山63/4级地震极震区烈度分布及发震构造 总被引:3,自引:0,他引:3
根据现场调查材料,对1936年4月1日广西灵山6 3/4级地震震中区烈度进行评定并绘制了等震线图。图中烈度Ⅸ、Ⅷ度区呈“T”形,两长轴方向与区内NEE及NNW方向断裂吻合。据此认为该震的发震构造为NEE和NNW两组断裂,6 3/4级地震系两组断裂共轭破裂的结果。又据低烈值沿NEE方向衰减较慢,认为NEE组断裂同时起控震构造作用。 相似文献
722.
Electrochemical Characterization of the Surface of Activated Carbon Used in Water Treatment Plants. We tried to measure electrochemically those properties of activated carbons which are important for using them for water purification. A success was achieved with the electrochemical immersion potential Ui which is found to be a function of concentration of functional surface groups on the carbon surface. However, the expected direct proportionality for inert surfaces between BET surface area and amount of charge measured in recharge processes has not been observed. 相似文献
723.
Serkan Sayin Fatih Ozcan Mustafa Yilmaz Ali Tor Shahabuddin Memon Yunus Cengeloglu 《洁净——土壤、空气、水》2010,38(7):639-648
In this study, 5,17‐bis‐[(4‐benzylpiperidine)methyl]‐25,26,27,28‐tetrahydroxy‐calix[4]arene ( 3 ) has been prepared by the treatment of calix[4]arene with a secondary amine (4‐benzylpiperidine) and formaldehyde by means of Mannich reaction. The prepared Mannich base ( 3 ) has been grafted onto [3‐(2,3‐epoxypropoxy)‐propyl]‐trimethoxysilane‐modified Fe3O4 magnetite nanoparticles (EPPTMS‐MN) in order to obtain 5,17‐bis‐[(4‐benzylpiperidine)methyl]‐25,26,27,28‐tetrahydroxy calix[4]arene‐grafted EPPTMS‐MN (BP‐calix[4]arene‐grafted Fe3O4). All new compounds were characterized by a combination of FTIR and 1H‐NMR analyses. The morphology of the magnetic nanoparticles was examined by transmission electron microscopy. Moreover, the studies regarding the removal of arsenate and dichromate ions from the aqueous solutions were also carried out by using 5,17‐bis‐[(4‐benzylpiperidine)methyl]‐25,26,27,28‐tetrahydroxy‐calix[4]arene in liquid–liquid extraction and BP‐calix[4]arene‐grafted Fe3O4 ( 4 ) in solid–liquid extraction experiments. The extraction results indicated that 3 is protonated at proton‐switchable binding sites in acidic conditions. Hence, facilitating binding of arsenate and dichromate is resulted from both electrostatic interactions and hydrogen bonding. To understand the selectivity of 3 , the retention of dichromate anions in the presence of Cl−, NO, and SO anions at pH 1.5 was also examined. 相似文献
724.
利用河北怀来4井1990年至2002年的水汞观测资料,对怀来4井汞量异常进行了分析,分析结果显示,怀来4井水汞异常与地震的对应率较好,1990年以来,其异常对于测点监测范围的有感地震及中小地震和距离测点较远的范围内发生的5.0级以上地震有很高的对应率。 相似文献
725.
用VLF、EH4和CSAMT方法寻找隐伏矿--以赤峰柴胡栏子金矿床为例 总被引:25,自引:9,他引:25
VLF、EH4和CSAMT均为基于电磁原理的地球物理手段,但它们在探测深度、测量精度和野外操作的复杂程度上有较大的差异.因而不同探测目标和精度要求,尽可能使用不同的方法或方法组合.VLF一般用于矿区及外围的地球物理扫面,以快速确定和发现覆盖层(不超过50~60 m)之下矿化构造系统的空间展布和基本规模.CSAMT具有探测深度大(>2000m)、工作效率高和抗干扰能力强等特点,一般用于确定矿化系统的深部的宏观几何形态和产状变化.EH4是这三种方法中对地下地质结构解析度最高、有效探测深度适中(800~1 200m)的一种地球物理测深方法,它可以解析较为精确地探测矿体的三维形态、规模、产状变化和细部结构但采集数据时对近场电磁干扰要求较高.这三种地球物理方法在赤峰柴胡栏子金矿区的联合应用,为寻找覆盖层之下隐伏矿体取得了良好的效果. 相似文献
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729.
The characterization of refractory organic substances (ROS) is very complicated because of their heterogeneous structure. Size-exclusion chromatography with continuous detection of dissolved nitrogen (LC-DN), dissolved organic carbon (LC-DOC), and UV-absorbance (LC-UV) is a very useful analytical tool for the characterization of changes of ROS in natural aquatic systems and in technological treatment. The effect of natural, oxidative, and biochemical processes on formation and removal of ROS is described. Additionally the role of hydrolysable carbohydrates in the composition of ROS is presented. 相似文献
730.
P. Gruszka 《洁净——土壤、空气、水》1999,27(5):374-382
The river Odra estuary belongs to those water bodies in the Baltic Sea area which are most exposed to immigration of alien species. Non-indigenous species that have appeared in the Szczecin Lagoon (i.a. Dreissena polymorpha, Potamopyrgus antipodarum, Corophium curvispinum) and in the Pomeranian Bay (Cordylophora caspia, Mya arenaria, Balanus improvisus, Acartia tonsa) in historical time and which now are dominant components of animal communities there as well as other and less abundant (or less common) alien species in the estuary (e.g. Branchiura sowerbyi, Eriocheir sinensis, Orconectes limosus) are presented. In addition, other newcomers – Marenzelleria viridis, Gammarus tigrinus, and Pontogammarus robustoides – found in the estuary in the recent ten years are described. The significance of the sea and inland water transport in the region for introduction of non-indigenous species is discussed against the background of the distribution pattern of these recently introduced polychaete and gammarid species. 相似文献