Capability of Pentavalent Arsenic Bioaccumulation and Biovolatilization of Three Fungal Strains under Laboratory Conditions

In order to control and remediate arsenic (As) contaminated soil, sediment or water, fungi are used to investigate their potential accumulation and volatilization of As. In this study, after cultivation for 2 days, the dry weights of mycelia for Trichoderma asperellum, Fusarium oxysporum and Penicillium janthinellum all show an increased trend when the As(V) concentration ranges from 0–50, 0–50, 0–80 mg/L, respectively. When the culture system is loaded with 2500 μg As(V), which represents 50 mg/L As, and cultivated for 5 days, P. janthinellum presents the highest efficiency of 87.0 μg/g for As bioaccumulation, and the order of the efficiency for As bioaccumulation is P. janthinellum > T. asperellum > F. oxysporum. However, the order of the amount of volatilized As is F. oxysporum > P. janthinellum > T. asperellum, and the highest amount of volatilized As is observed for F. oxysporum at 181.0 μg. Thus, the ability of As bioaccumulation and biovolatilization for T. asperellum and P. janthinellum is reported for the first time in this study.     

Love wave tomography in Italy from seismic ambient noise

We estimate Love wave empirical Green's functions from cross-correlations of ambient seismic noise to study the crust and uppermost mantle structure in Italy.Transverse-component ambient noise data from October 2005 through March 2007 recorded at 114 seismic stations from the Istituto Nazionale di Geofisica e Vulcanologia (INGV) national broadband network,the Mediterranean Very Broadband Seismographic Network (MedNet) and the Austrian Central Institute for Meteorology and Geodynamics (ZAMG) yield more than 2 000 Love wave group velocity measurements using the multiple-filter analysis technique.In the short period band (5-20 s),the cross-correlations show clearly one-sided asymmetric feature due to non-uniform noise distribution and high local activities,and in the long period band (20 s) this feature becomes weak owing to more diffusive noise distribution.Based on these measurements,Love wave group velocity dispersion maps in the 8-34 s period band are constructed,then the SH wave velocity structures from the Love wave dispersions are inverted.The final results obtained from Love wave data are overall in good agreement with those from Rayleigh waves.Both Love and Rayleigh wave inversions all reveal that the Po plain basin is resolved with low velocity at shallow depth,and the Tyrrhenian sea is characterized with higher velocity below 8 km due to its thin oceanic crust.     

中小震近场地震动估计中地震动衰减关系的适用性分析

核工程场地设计基准地震动确定中涉及弥散地震的地震动估计，这导致中小震近场地震动估计成为被关注的研究课题。本文基于一些中小震近场地震动记录资料，分析和探讨了国内外多种地震动衰减关系对中小震近场地震动估计的适用性问题，并结合我国几个核工程地震问题研究工作的实践对中小震近场地震动衰减关系确定的思路和原则提出了建议。     

考虑土体固液二相性质的地下管线地震反应研究

本文将管线周围的土体视为固-液二相介质，采用考虑地震过程中土体内孔隙水压力的增长和消散的有效应力分析方法，并以非线性的土体本构模型模拟土体动力特性的改变以及在孔隙水压作用下的变形，以求接近土体的真实地震反应。研究表明随着土体软化程度的不同，受到土体约束的管线应力亦发生相应变化。文中详细研究了地震动峰值、管线直径、行波波速和入射角度等对管线应力的影响。     

Gongzhucuo Massif: An Ever Slightly Depleted Peridotite in the Western Yarlung Zangbo Ophiolitic Belt of Southern Tibet

<正>The Gongzhucuo ophiolite,located near Lake Gongzhu in SW Tibet,occurs in the southern ophiolite sub-belt along the western Yarlung Zangbo suture zone.It is is mainly composed of harzburgitic and lherzolitic upper mantle peridotites,intruded by mafic dikes.The mantle     

伊利石40Ar-39Ar年龄的统计分析与成藏期

为了确定鄂尔多斯盆地苏里格气田的成藏年代,通过提取砂岩储层中的黏土质填隙物,分离分级成 < 0.5、0.5~1.0、1.0~2.0μm的分样品,进行伊利石激光阶段加热40Ar-39Ar定年.等时线年龄是自生伊利石与碎屑伊利石的混合年龄.通过趋势分析和回归分析分别获得极小的趋势年龄和极小的回归年龄,该年龄比较接近自生伊利石年龄.测试结果表明,伊利石的等时线年龄介于160.9~232.0 Ma之间,为自生伊利石与碎屑伊利石的混合年龄.采用数理统计方法获得极小趋势年龄和极小回归年龄分别为151.7 Ma和152.4 Ma,该年龄比较接近自生伊利石年龄,代表了热流体活动和油气成藏时间.      

河北坝上高原小滦河流域古土壤碳库地质成因和稳定性评价

土壤碳库是陆地生态系统中最大的碳库，以往研究主要针对现代土壤碳库，而古土壤的碳库特征研究相对薄弱。本文以河北坝上高原小滦河流域古土壤为研究对象，通过光释光（OSL）年代学、元素地球化学、团聚体分析方法，研究了风成沙地稀疏草地单元和河湖残积灌草混合单元内古土壤碳库特征。结果表明：古土壤形成时代为5. 7~3. 3 ka的全新世温暖期，气候温暖湿润，雨水充足，发育以松和蒿属为主要建群种的针叶林－草原植被。碳库以有机碳（SOC）为主，平均有机碳密度为3. 85 kg/m2，有机碳库储量为153. 1×107 kg。河湖相沉积物微团聚体的含量较高，对古土壤层碳库的物理保护作用较强，碳库稳定性较高；风积相沉积物微团聚体含量相对较低，加速有机碳的分解，碳库稳定性较差。提出不同沉积单元的土地利用保护方式，减少土壤有机碳的分解流失，支撑当地碳达峰、碳中和工作推进。     

Influence Mechanism of Mine Pressure on Coal Seam Gas Emission During Mining

Geotechnical and Geological Engineering - Gas is one of the main factors causing coal mine accidents in China. Understanding the mechanism of the influence of mine pressure on coal seam gas...     

区域地下水流理论的发展历程与教材演变

Tóth提出的区域地下水流理论为盆地尺度地下水循环研究提供了定量分析方法.从4个方面总结区域地下水流理论发展历程,对比国外多本水文地质学教科书对区域地下水流理论的描述情况,系统梳理我国《水文地质学基础》教科书自1986到2018年的4个版本对区域地下水理论描述的演变情况.分析认为,我国《水文地质学基础》教科书对我国学者开展区域地下水流研究发挥了重要的推动作用,最后提出了区域地下水流理论有待解决的科学问题和引导更多青年学生从事该领域研究的建议.