会泽铅锌矿床中自然锑的发现及伴生元素的分布特征

文章对会泽铅锌矿床的主要矿体进行了系统观察、采样，对其矿石进行了岩矿鉴定、化学分析(包括部分单矿物)和电子探针分析，并对其成矿作用做了探讨。首次在矿石中发现了自然锑，初步查明整个矿床中Ag，Cd，Ge，Cu，Sb等伴生元素的平均含量(wB／10^-6)分别为121．77、660．99、62．10、203．78和169．87，认为它们是晚成矿阶段形成的。     

大埋深条件下降雨入渗补给的初步分析

运用SWAP模型对太行山山前平原--河北省栾城县田间土壤水分运动进行了数值模拟.从土水势及土壤含水量等方面,初步分析了降雨灌溉入渗补给条件下土壤水分运动的规律.通过分析和讨论,探求了大埋深条件下降雨入渗过程,初步揭示了降雨入渗对地下水位变化的影响.     

Theory and application for retrieval and fusion of spatial and temporal quantitative information from complex natural environment

This paper briefly presents the research progress of the State Major Basic Research Project 2001CB309400, “Theory and Application for Retrieval and Fusion of Spatial and Temporal Quantitative Information from Complex Natural Environment”. Based on the rapid advancement of synthetic aperture radar (SAR) imagery technology, information theory of fully polarimetric scattering and applications in polarimetric SAR remote sensing are developed. To promote the modeling of passive microwave remote sensing, the vector (polarized) radiative transfer theory (VRT) of complex natural media such as inhomogeneous, multi-layered and 3-dimensional VRT is developed. With these theoretical progresses, data validation and retrieval algorithms for some typical events and characteristic parameters of earth terrain surfaces, atmosphere, and oceans from operational and experimental remote sensing satellites are studied. Employing remote sensing, radiative transfer simulation, geographic information systems (GIS), land hydrological process, and data assimilation, the Chinese land data assimilation system (CLDAS) is established. Towards the future development of China’s microwave meteorological satellites, employing remote sensing data of currently available SSM/I (special sensor microwave/imager), AMSU (advanced microwave sounding unit), MTI (microwave temperature imager), etc., with ground-based measurements, several operational algorithms and databases for atmospheric precipitation, water vapor and liquid water in clouds, and other hydrological/hydrological applications are developed. To advance China’s SAR and InSAR (interferometric SAR) technologies, the image processing and analysis of ERS (European remote sensing), Radarsat SAR, and Chinese SAR, etc., the software platforms are accomplished. Based on the researches of multi-information fusion, some simulations, identification, and information extractions of the targets from complex background clutter scenes are studied. Some experiments of radio wave propagation in anomalous atmospheric status are also carried out. Translated from Advances in Earth Science, 2007, 22(2): 111–125 [译自: 地球科学进展]     

Focal mechanisms of recent earthquakes in the Southern Korean Peninsula

We evaluate the stress field in and around the southern Korean Peninsula with focal mechanism solutions, using the data collected from 71 earthquakes ( M_L = 1.9–5.2) between 1999 and 2004. For this, the hypocentres were relocated and well-constrained fault plane solutions were obtained from the data set of 1270 clear P -wave polarities and 46 SH / P amplitude ratios. The focal mechanism solutions indicate that the prevailing faulting types in South Korea are strike-slip-dominant-oblique-slip faultings with minor reverse-slip component. The maximum principal stresses (σ₁) estimated from fault-slip inversion analysis of the focal mechanism solutions show a similar orientation with E–W trend (269°–275°) and low-angle plunge (10°–25°) for all tectonic provinces in South Korea, consistent with the E–W trending maximum horizontal stress (σ_Hmax) of the Amurian microplate reported from in situ stress measurements and earthquake focal mechanisms. The directions of the intermediate (σ₂) and minimum (σ₃) principal stresses of the Gyeongsang Basin are, however, about 90 deg off from those of the other tectonic provinces on a common σ₂–σ₃ plane, suggesting a permutation of σ₂ and σ₃. Our results incorporated with those from the kinematic studies of the Quaternary faults imply that NNW- to NE-striking faults (dextral strike-slip or oblique-slip with a reverse-slip component) are highly likely to generate earthquakes in South Korea.     

Nonlinear seismic response analysis of arch dam-foundation systems- part II opening and closing contact joints

A time-domain method for the analysis of arch dam-foundation rock dynamic interaction during earthquake was proposed, and the dynamic relaxation technique was adopted to obtain the initial static response for dynamic analysis by [Du et al. (2005). The paper has been contributed to Bulletin of earthquake engineering]. In this paper, a nonlinear explicit method in time domain considering the opening and closing effect of contact joints on arch dam during earthquake is further proposed by introducing the dynamic contact force model into the method. The simulation accuracy of dynamic contact force model is verified by comparing its calculation result and test result of scale model on shaking table. Finally, the influence of joints on the seismic response of Xiaowan arch dam is studied by the proposed method and some conclusions are given.     

Paleoenvironment evolution of the East Philippine Sea recorded in the new-type ferromanganese crust since the terminal Late Miocene

From systemic research of microstructure, geochemistry, uranium-series and 10Be isotope dating on a new-type deepwater ferromanganese crust from the East Philippine Sea, the paleoenvironment evolu-tion of the target area since the terminal Late Miocene was recovered. The vertical section changes of microstructure and chemical composition are consistent in the studied crust, which indicate three major accretion periods and corresponding paleoenvironment evolution of the crust. The bottom crust zone was formed in the terminal Late Miocene (5.6 Ma) with loose microstructure, high detritus content and high growth rate. Reductions of mineral element content, accretion rate and positive Ce-anomaly degree at 4.6 Ma indicate temporal warming, which went against the crust accretion and finally formed an accretion gap in the terminal Middle Pliocene (2.8―2.7 Ma). The more active Antarctic bottom sea-waters in the Late Pliocene (2.7 Ma) facilitated the fast transfer to the top pure crust zone. Hereafter, with the further apart of volcanic source and the keeping increase of eolian material (1.0 Ma), although surrounding conditions were still favorable, mineral element content still shows an obvious reducing trend. It thereby offers new carrier and data for the unclear paleoceanographic research of the target area since the terminal Late Miocene.     

Cleaning Using CO2‐Based Solvents

Cleaning with hierarchy of CO₂‐based solvents is advantageous from an environmental point of view because CO₂ is non‐flammable, virtually inert, and abundant. After cleaning, the only waste stuffs generated are the contaminants that are removed from the cleaned parts. The technology is especially well suited for precision cleaning applications in which parts have intricate geometries or for applications in which parts are sensitive to water or high temperature. This review will first introduce aqueous cleaning concepts and mechanism, which is helpful to understand how to design cleaning systems using high pressure CO₂. Recent microelectronic processes for cleaning and rising of circuit wafers using CO₂‐based solvents are the main focus of the review. Additional cleaning topics include dry cleaning, separation of dyestuffs, and extraction of contaminations from soils and regeneration of catalysts.