铅在高岭石表面的解吸动力学   总被引：3，自引：0，他引：3  

魏俊峰  吴大清  彭金莲  刁桂仪 《矿物岩石》2002,22(2):5-8

经过酸性条件下（pH=3.1)Pb(Ⅱ）高岭石表面解吸动力学的研究，发现解吸反应与吸附反应动力学相似，也是一个二阶段的过程，即初始的快速解吸之后伴随着一个缓慢的释放过程。在快速解吸阶段，7min内解吸量即已达到41％。吸附铅没有完全解吸，有近38％残留在高岭石表面，即解吸和吸附过程不是完全可逆的。解吸过程可以用扩展Elovich方程、Elovich方程、双常数方程和一级扩散方程较好地似合。  相似文献   

Predicting Terrestrial Flagstone Reservoirs in the Sha-I Member of the Qibei Depression in the Dagang Oilfield     

LEI Huaiyan  LIU Zhihong  XU Maoquan  GUAN Baocong Institute of Oceanography  Environment  Xiamen University  Xiamen  Fujian State Key Laboratory of Gas Geochemistry  Institute of Geology  Chinese Academy of Sciences  Lanzhou  Gansu 《《地质学报》英文版》2004,78(3):701-714

There are few 3-D seismic profiles and drillings in the middle part of the Qibei depression in the Dagang oilfield, and more than 70% of the 2-D seismic profiles were completed before the 1980s. Meanwhile, changes in the terrestrial formations in this region have been large and complex. These factors have made it difficult to predict reservoirs in this area. The purpose of this paper is to establish a methodology for predicting potential gas and oil reservoirs. Our research combines sequence stratigraphy, well-logs, and seismic analysis to elucidate the prediction of flagstone reservoirs in the S1 (Sha-I) Member in the middle of the Qibei depression. Previous research indicates that these rocks were deposited in an environment that had a semiarid, northern subtropical, and warm, humid climate. The objective strata currently consist mainly of lake fades, deeper lake facies, and shore-shallow lake facies. The study reveals that the lower section of the S1 Member is an important objective region for explora  相似文献   

珠江口滨海湿地退化现状、原因及保护对策   总被引：1，自引：0，他引：1  

李团结  马玉  王迪  王爱军  周英 《热带海洋学报》2011,(4)

2007年和2008年秋季对珠江口滨海湿地进行了环境现状综合调查,结果表明,珠江口滨海湿地退化主要表现在4个方面:天然湿地面积减少、湿地生产力不断下降、湿地环境状况持续恶化和湿地景观破碎化。珠江口滨海湿地退化的原因主要为滩涂开发与围填海、污染物排放、养殖污染、海平面上升、过度捕捞、海砂开采和港口码头建设以及水土资源开发等因素。滨海湿地保护与利用对策主要有:制定有关滨海湿地保护的法律法规和湿地保护与利用规划;加强人才队伍建设和滨海湿地有关技术研究;建立滨海湿地动态监测体系;加大滨海湿地保护区建设的力度;加强宣传和教育。  相似文献   

水环境地球物理方法的应用综述   总被引：4，自引：0，他引：4  

杨进  刘庆成  程业勋  王南萍  侯胜利 《地质科技情报》2000,19(2):107-110

给出了水资源调查的环境地球物理方法,通过实例讨论了水环境地球物理方法在地下水资源的勘测、保护和水污染监测方面的应用效果。  相似文献   

林业技术开发试验示范区管理模式、运行机制及政策     

福建省南平市林业技术开发试验示范区 《湿地科学与管理》2000,(1):36-40

<正> 南平林业技术开发试验示范区是在1990年5月南平市政府(原地区行署)与中国林科院签订了长期友好合作,共建技术开发试验区协议的基础上,于1992年8月林业部正式批准成立的。 南平林业技术开发试验示范区的范围为南平市所辖10个县(市、区)行政区域,总面积26031平方公里(263.18万公顷),总人口300万人。山地面积217.28万公顷,有林地  相似文献   

Coupled BEM-FEM Analysis of the Large-Diameter Cylinder Structure System   总被引：2，自引：0，他引：2  

Zhou Xireng  Duan Xudong  Sang Xuezhu Zhang Rui  Dai Jialu Professor  Tianjin University  Tianjin Engineer  Xiamen Port Office  Fujian Lecturer  Tianjin University  Tianjin Senior Engineer  Tianjin Port Office  Tianjin 《中国海洋工程》1992,(2)

A method of coupled BEM-FEM analysis for the elastic spatial structure system is presented. It can be applied to the calculation of the stress and deformation of the large-diamater cylinder structure system and it is suitable for symmetric or non-symmetric structures under the distributed or concentrated load. Numerical examples show that the proposed method and computer program BEFEM are quite efficient in the analysis of the large-diameter cylinder structure problems in ocean engineering.  相似文献   

海水养殖与生态环境关系的研究——Ⅰ.无机氮对浮游植物生长的影响     

李文权  郑爱榕  李淑英 《热带海洋学报》1993,(3)

采用中尺度受控生态实验、小型混养实验和虾池取样测定,研究海水中无机氮、N/P比值和藻类光合作用速率的变化规律,分析了无机氮和溶解有机氮(DON)的相互转化,比较了钙质角毛藻对不同形式无机氮的吸收,探讨了人工养殖海水中无机氮对浮游植物生长的影响。  相似文献   

南沙群岛海域风场特征--卫星散射计观测资料分析   总被引：2，自引：1，他引：2  

郭小钢  靖春生  李立 《热带海洋学报》2003,22(4):18-25

通过对欧空局提供的ERS卫星微波散射计风场资料的再分析，研究了南沙群岛海域的风场特征，主要包括南沙群岛海域的东北季风和西南季风随纬度的变化以及一年中根据风应力特征划分的4个时期的风应力与风应力旋度的分布特征。  相似文献   

A new type of isotopic anomaly in shergottite sulfides     

Heather B. Franz  Nanping Wu  James Farquhar  Anthony J. Irving 《Meteoritics & planetary science》2019,54(12):3036-3051

The isotopic composition and abundance of sulfur in extraterrestrial materials are of interest for constraining models of both planetary and solar system evolution. A previous study that included phase‐specific extraction of sulfur from 27 shergottites found the sulfur isotopic composition of the Martian mantle to be similar to that of terrestrial mid‐ocean ridge basalts, the Moon, and nonmagmatic iron meteorites. However, the presence of positive Δ³³S anomalies in igneous sulfides from several shergottites, indicating incorporation of atmospherically processed sulfur into the subsurface, complicated this interpretation. The current study expands upon the previous work through analyses of 20 additional shergottites, enabling tighter constraints on the isotopic composition of juvenile Martian sulfur. The updated composition (δ³⁴S = ?0.24 ± 0.05‰, Δ³³S = 0.0015 ± 0.0016‰, and Δ³⁶S = 0.039 ± 0.054‰, 2 s.e.m.), representing the weighted mean for all shergottites within the combined population of 47 without significant Δ³³S anomalies, strengthens our earlier result. The presence of sulfur isotopic anomalies in igneous sulfides of some meteorites suggests that their parent magmas may have assimilated crustal material. We observed small negative Δ³³S anomalies in sulfides from two meteorites, NWA 7635 and NWA 11300. Although negative Δ³³S anomalies have been observed in nakhlites and ALH 84001, previous anomalies in shergottites have all shown positive values of Δ³³S. Because NWA 7635 has formation age of 2.4 Ga and is much more ancient than shergottites analyzed previously, this finding expands our perspective on the continuity of Martian atmospheric sulfur photochemistry over geologic time.  相似文献   

高低压中心、槽线识别的初步试验     

袁美英  徐南平  于振东 《气象》1994,20(6):15-19

利用经过截取处理的欧亚范围的欧洲格点数据，通过运算转化为屏幕网格资料，采用逐点追踪方法绘制等压线，运用统计识别法和模糊识别技术，结合实测风场订正，对高低压中心和槽线进行分析识别。试验结果表明，计算机能基本准确的识别出高低压中心及槽线，且速度比人工快得多，从而可做为人工智能工作站的一相接口，并为天气图的客观化和自动化分析作了初步尝试。  相似文献