An implementation of rock engineering system for ranking the instability potential of natural slopes in Greek territory. An application in Karditsa County   总被引：1，自引：0，他引：1  

D. Rozos  L. Pyrgiotis  S. Skias  P. Tsagaratos 《Landslides》2008,5(3):261-270

This paper presents an application of rock engineering system (RES) in an attempt to reveal and assess the inherent instability potential of 388 sites where equivalent landslides have been manifested and recorded in the region of Karditsa County, Greece. The main objective has been defining the principal causative and triggering factors responsible for the manifestation of landslide phenomena, quantify their interactions, obtain their weighted coefficients, and calculate the instability index, which refers to the inherent potential instability of each natural slope of the examined region. From the statistical interpretation of the data reported in a well-documented database and concerning the examined failure sites, a clear correlation between the instability index and the area affected by a single landslide event has been revealed. Almost the entire failure sites, 98% of the examined slope sites, exhibit an instability index value over 55, a value which is thought to be a critical threshold for landslide manifestation concerning natural slopes in Karditsa County. It is argued that the presented RES methodology, engaging the selected set of parameters, could be considered as an effective expert's tool for ranking, in an objectively optimal and simple way, the instability potential of natural slopes in Karditsa County, and thus providing a tool for sound zoning landslide hazard.  相似文献   

Contextual Spatiospectral Postreconstruction of Cloud-Contaminated Images   总被引：1，自引：0，他引：1  

Benabdelkader  S. Melgani  F. 《Geoscience and Remote Sensing Letters, IEEE》2008,5(2):204-208

A general method has been proposed recently for the contextual reconstruction of cloud-contaminated areas in multitemporal multispectral images. It is based on the idea of making the prediction process learn from information available in the cloud-free neighborhood of contaminated areas. Though promising, this method does not fully exploit all available information, thus leaving room for further methodological enhancements. This letter presents a postreconstruction methodology for improving the contextual reconstruction process by opportunely capturing spatial and spectral correlations characterizing the considered image. In addition, we propose a solution to a problem that has not yet been addressed in the remote sensing literature, i.e., the generation of an error map beside the reconstructed images to provide end-users with helpful indications about reconstruction reliability. Thorough experiments conducted on a multitemporal sequence of Landsat-7 ETM+ images are reported and discussed.  相似文献   

A New Algorithm for Wind-Vector Retrieval From Scatterometers     

Gohil  B.S. Sarkar  A. Agarwal  V.K. 《Geoscience and Remote Sensing Letters, IEEE》2008,5(3):387-391

A new efficient algorithm for retrieving wind-vector solutions from scatterometers is developed based on a criterion of minimum normalized standard deviation (NSD) of wind speed derived from backscatter measurements using a geophysical model function (GMF). Its performance has been evaluated through simulations using QSCAT-1 GMF and the QuikSCAT observational geometry. The present algorithm, named the NSD algorithm, is found to be computationally more efficient (two to three times) besides being at par with the maximum-likelihood estimator (MLE) algorithm in terms of retrieval skill, retrieval errors, and distribution of solutions, on the basis of simulations as well as comparison of limited QuikSCAT-data-derived winds with National Centers for Environmental Prediction and European Centre for Medium-Range Weather Forecasts model winds. Simulation results and analysis of sample QuikSCAT data are presented.   相似文献   

Assessment of cement’s dust impact on the soil using principal component analysis and GIS   总被引：2，自引：1，他引：1  

Z. Zerrouqi  M. Sbaa Ph.D.  M. Oujidi Ph.D.  M. Elkharmouz  S. Bengamra  A. Zerrouqi 《International Journal of Environmental Science and Technology》2008,5(1):125-134

To evaluate the impact of the cement’s dust emitted by the eastern Moroccan cement factory (Oujda Holcim) and deposited on the soil of the Ain Lahjar commune, 58 samples of soil were collected around the factory on a radius of 3 km approximately. The physicochemical analyses of the upper 3 cm of the soil surface samples correspond to the pH, electrical conductivity, the chlorides and the oxides of Ca, Al, Fe, K, Mn, S and Si which were analyzed by the fluorescence of X-rays. The preliminary results demonstrate that this dust are especially basic and contain a high free lime (43% CaO). The principal component analysis (applied on the 58 samples of soil) allows deducting that the free lime and the sulfur oxide are the tracer elements of this form of pollution. Furthermore, the spatial projection of the factor scores of the principal component analysis using the geographical information system permits to determine the spatial distribution of more polluted areas of soils as well as to estimate their surface (63.3% of the survey zone).  相似文献   

Transient and spatial modeling and simulation of polybrominated diphenyl ethers reaction and transport in air, water and soil   总被引：1，自引：0，他引：1  

M. Mousavi Ph.D.  S. Kiani  S. Lotfi  N. Naeemi  M. Honarmand 《International Journal of Environmental Science and Technology》2008,5(3):323-330

The release of the wastes containing polybrominated diphenyl ethers into the environment is a worldwide major concern. Investigation of spatial and temporal variations of polybrominated diphenyl ethers concentrations due to different factors, especially the transport of these species between air and water as well as between air and soil is the purpose of present research. A model was developed and solved using the methods of finite difference and lines. Simulations were implemented for three dimensions of width, length, and height and also time for the air compartment, whereas for the soil and water compartments, variations were considered only with respect to height and time. Transport between water and soil was disregarded for simplicity at this stage. Vancouver’s landfill was considered as a case study. Lower concentrations in air and higher concentrations in water at the interface show that these pollutants tend to diffuse from air to water. Concentrations of all four pollutants decrease near the interface in soil as time passes, but they are predicted to be almost constant at other levels.  相似文献   

Ability of indigenous Bacillus licheniformis and Bacillus subtilis in microbial enhanced oil recovery   总被引：1，自引：1，他引：0  

S. Haghighat  A. Akhavan Sepahy Ph.D.  M. Mazaheri Assadi Ph.D.  H. Pasdar Ph.D. 《International Journal of Environmental Science and Technology》2008,5(3):385-390

Microbially produced lipopeptide have been isolated and studied for microbial enhanced oil recovery. About 60 gram positive bacteria isolated from soil contaminated with crude oil, near the crude oil storage tank in Tehran Refinery, Tehran, Iran. However, most of these studies have produced lipopeptide by one of the pure-culture microbes isolated in a laboratory. Among the isolates, heamolytic tests revealed two biosurfactant producers. The isolated strains were designated as C2, E1. By using morphological, biochemical and molecular biology tests (16 SrRNA), the strains identified as Bacillus licheniformis and Bacillus subtitlis, respectively. Emulsification activity and measurement of surface tension indicated that, the isolates were high producers of biosurfactant. The product of C2 and E1 is mainly lipopeptide. This product reduce surface tension from 65 to 30 mN/m. Emulsified activity of crude oil was 92% for C2 and 90 % in case of E1. This is the first report of indigenous Bacillus licheniformis and Bacillus subtilis from a soil contaminated with oil in an Iranian refinery with ability to produce biosurfactant.  相似文献   

Modeling study of the effects of the coagulation kernel with van der Waals forces and turbulence on the particle size distribution     

S. Cho M.Sc.  Ph.D.  D. V. Michelangeli M.Sc.  Ph.D. 《International Journal of Environmental Science and Technology》2008,5(1):1-10

In this study, variations in the size distributions due to different assumptions for the coagulation kernel are investigated. In order to evaluate how the coagulation kernel influences the form of the particle size distribution and to describe the process of the Brownian coagulation, the Brownian coagulation kernel, including the van der Waals forces, is compared with the most frequently used coagulation coefficients. Retardation should be considered for interparticle interactions for particles larger than 1μm radius. However, for particle sizes larger than 0.1 μm, the Brownian kernel is not dominant, so the retardation effect can be ignored. The inclusion of the van der Waals forces in the Brownian coagulation kernel caused a faster coagulation process in the small particle size range. Taking account of the turbulent coagulation kernel, the turbulent coagulation kernel becomes more important when the turbulent intensity is higher. The turbulent coagulation kernel affects the large particle size range and ignoring the turbulent coagulation kernel will lead to overestimation of particle number concentration in model simulation. The results of this study indicate that the inclusion of van der Waals forces or the turbulent coagulation kernel in the total coagulation kernel impacts on the modeled particle size distributions and total particle number concentration.  相似文献   

Saraca indica leaf powder for decontamination of Pb: removal, recovery, adsorbent characterization and equilibrium modeling   总被引：5，自引：5，他引：0  

P. Goyal  P. Sharma  S. Srivastava  M. M. Srivastava 《International Journal of Environmental Science and Technology》2008,5(1):27-34

The present study explores the effectiveness of Saraca indica leaf powder, a surplus low value agricultural waste, in removing Pb ions from aqueous solution. The influence of pH, biomass dosage, contact time, particle size and metal concentration on the removal process were investigated. Batch studies indicated that maximum biosorption capacity for Pb was 95.37% at the pH 6.5. The sorption process followed the first order rate kinetics. The adsorption equilibrium data fitted best to both Langmuir and Freundlich isotherms. Morphological changes observed in scanning electron micrographs of untreated and metal treated biomass confirmed the phenomenon of biosorption. Fourier transform infrared spectroscopy of native and exhausted leaf powder confirmed lead biomass interactions responsible for sorption. Acid regeneration was tried for several cycles with a view to recover the sorbed metal ion and also to restore the sorbent to its original state. The findings showed that Saraca indica leaf powder can easily be envisaged as a new, vibrant, low cost biosorbent for metal clean up operations.  相似文献   

Geochemistry of magmatic rocks of the Koksharovka alkaline-ultrabasic massif,primorye, and results of trace-element modeling     

R. A. Oktyabrsky  A. A. Vrzhosek  A. M. Lennikov  T. A. Yasnygina  S. V. Rasskazov  E. Yu. Moskalenko  T. A. Velivetskaya 《Russian Journal of Pacific Geology》2008,2(4):325-335

New geochemical data are presented on the magmatic rocks of the Late Jurassic Koksharovka alkaline-ultrabasic massif, which is associated with deposits of vermiculite, apatite, V-bearing titanomagnetite, and placer isoferroplatinum. The REE geochemistry and strontium, oxygen, and carbon isotopic composition of carbonatites and related ijolites and pyroxenites, together with geological observations, point to the magmatic origin of the Koksharovka carbonatites. The origin of associated magmatic rocks is discussed. Trace element modeling of partial melting of mantle sources was conducted to decipher the genesis of the melts of the Koksharovka carbonatites and host titanite-kaersutite pyroxenites.  相似文献   

Paleomagnetic studies of the Late Mesozoic deformation stage in the southern Primorye region     

S. V. Shipunov  Yu. S. Bretshtein  A. V. Zhuravlev 《Russian Journal of Pacific Geology》2008,2(4):344-353

The analysis of paleomagnetic data available for the southern Primiorye region revealed that the studied objects were magnetized under regional remagnetization presumably during the Late Mesozoic folding and this magnetization can be interpreted as being synfolding. The interpretation is based on the parameter that characterizes the folding completion degree immediately before regional remagnetization. It is shown that the relaxation of Late Mesozoic horizontal stresses was irregular. The obtained estimates of the degree of folding completion are consistent with the available geological data and Talitskii’s model for tectonic deformations.  相似文献