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Journal of Earth Science 2015年第6期26卷 785-790页

作者： J.German Rubino Beatriz Quintal Tobias M.Muller Luis Guarracino Ralf Janicke Holger Steeb Klaus Holliger applied and environmental geophysics group Institute of Earth Sciences University of Lausanne Energy Flagship Commonwealth Scientific and Industrial Research Organization CONICET Facultad de Ciencias Astronomicasy Geofisicas Universidad Nacional de La Plata Institute of Mechanics University of Bochum

An important characteristic of fractured rocks is their high seismic attenuation, which so far has been mainly attributed to wave-induced fluid flow（WIFF） between the fractures and the embedding matrix. The influence of fracture connectivity on seismic attenuation has, however, recently, only been investigated. Numerical compressibility and shear tests based on Biot＇s quasi-static poro-elastic equations illustrate that an important manifestation of WIFF arises in the presence of fracture connectivity. The corresponding energy loss, which can be significant for both P- and S-waves, is mainly due to fluid flow within the connected fractures and is sensitive to the permeabilities as well as the lengths and intersection angles of the fractures. Correspondingly, this phenomenon contains valuable information on the governing hydraulic properties of fractured rocks and hence should be accounted for whenever realistic seismic models of such media are needed.

关键词： fractured rocks seismic attenuation WIFF fracture connectivity embedding matrix Biot’s theory

Mercury uptake and effects on growth in Jatropha curcas

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Journal of environmental Sciences 2016年第10期28卷 120-125页

作者： Jose Marrugo-Negrete Jose Durango-Hernandez Jose Pinedo-Hernandez German Enamorado-Montes Sergi Diez University of Cordoba Faculty of Basic Sciences Department of Chemistry Water Applied and Environmental Chemistry Group Monteria Colombia environmental Chemistry Department Institute of Environmental Assessment and Water Research ID█A-CSIC E-08034 Barcelona Spain

The use of metal-accumulating plants for the phytoremediation of contaminated soils is gaining more attention. Mercury （Hg）-contaminated soils from historical gold mines represent a potential risk to human health and the environment. Therefore, Jatropha curcas plant, that has shown its tolerance to these environments, is a species of particular interest to implement phytoremediation techniques in gold mining sites. In this work, the behavior of J. curcas was assessed in different hydroponic cultures fortified with Hg at concentrations of 5, 10, 20, 40, and 80μg Hg/mL （T5, T10, T20, T40 and T80, respectively）. After exposure, plant growth, net photosynthesis, leaf area, and Hg accumulation were determined and variables such as net Hg uptake, effective Hg accumulation, translocation and bioaccumu- lation factors were calculated. Accumulation of Hg in root and leaf tissues increased with respect to the Hg concentrations in the hydroponic culture, with statistically significant differences （p 〈 0.05） among treatments. Moreover, Hg concentration in roots was 7 and 12-fold higher in average than in plant leaves and shoots, respectively. Many effects were found in the development of plants, especially related with loss of biomass and leaf area, with significant growth inhibition related to control values （〉50% with treatment T5）. Moreover, percentage of inhibition was even higher （〉60%） with same treatment for net photosynthesis. Finally, it should be highlighted that for T40 and T80 treatments, plant growth and photosynthesis were almost completely depleted （88%-95%）.

关键词： Jatropha curcasPhytoextractionMercuryHydroponicGrowth inhibition

Comprehensive Approach for Porous Materials Analysis Using a Dedicated Preprocessing Tool for Mass and Heat Transfer Modeling

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Journal of Thermal Science 2018年第5期27卷 479-486页

作者： MADEJSKI Pawel KRAKOWSKA Paulina HABRAT Magdalena PUSKARCZYK Edyta JEDRYCHOWSKI Mariusz Department of Power Systems and environmental Protection Facilities Faculty of Mechanical Engineering and Ro-botics AGH University of Science and TechnologyKraków 30-059 Poland Department of geophysics Faculty of Geology Geophysics and Environmental Protection AGH University of Sci-ence and Technology Kraków 30-059 Poland Department of Geoinformatics and applied Computer Science Faculty of Geology Geophysics and Environmental Protection AGH University of Science and TechnologyKraków 30-059 Poland Department of Condensed Matter Physics Faculty of Physics and Applied Computer Science AGH University of Science and TechnologyKraków 30-059 Poland

The paper presents a comprehensive, newly developed software – poROSE(poROus materials examination SoftwarE) for the qualitative and quantitative assessment of porous materials and analysis methodologies developed by the authors as a solution for emerging challenges. A low porosity rock sample was analyzed and thanks to the developed and implemented methodologies in poROSE software, the main geometrical properties were calculated. A tool was also used in preprocessing part of the computational analysis to prepare a geometrical representation of the porous material. The basic functions as elimination of blind pores in the geometrical model were completed and the geometrical model was exported for CFD software. As a result, it was possible to carry out calculations of the basic properties of the analyzed porous material sample. The developed tool allows to carry out quantitative and qualitative analysis to determine the most important properties characterized porous materials. In presented tool the input data can be images from X-ray computed tomography(CT), scanning electron microscope(SEM) or focused ion beam with scanning electron microscope(FIB-SEM) in grey level. A geometric model developed in the proper format can be used as an input to modeling mass, momentum and heat transfer, as well as, in strength or thermo-strength analysis of any porous materials. In this example, thermal analysis was carried out on the skeleton of rock sample. Moreover, thermal conductivity was estimated using empirical equations.

关键词： porous materials rock software thermal properties preprocessing

Comparison of two projection methods for modeling incompressible flows in MPM

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Journal of Hydrodynamics 2017年第3期29卷 405-412页

作者： Shyamini Kularathna Kenichi Soga Department of Engineering Geotechnical and Environmental Research GroupUniversity of Cambridge Department of Civil and environmental Engineering University of California Berkeley

Material point method（MPM）was originally introduced for large deformation problems in solid mechanics ***,it has been successfully applied to solve a wide range of material ***,previous research has indicated that MPM exhibits numerical instabilities when resolving incompressible flow *** study Chorin＇s projection method in MPM algorithm to simulate material *** projection-type schemes,non-incremental projection and incremental projection,are investigated for their accuracy and stability within *** examples show that the non-incremental projection scheme provides stable results in single phase MPM ***,it avoids artificial pressure oscillations and small time steps that are present in the explicit MPM approach.

关键词： Chorin's projection method material point method(MPM) incompressible flow time step

Numerical simulation of superhalo electrons generated by magnetic reconnection in the solar wind source region

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Research in Astronomy and Astrophysics 2015年第3期15卷 348-362页

作者： Li-Ping Yang Ling-Hua Wang Jian-Sen He Chuan-Yi Tu Shao-Hua Zhang Lei Zhang Xue-Shang Feng School of Earth and Space Sciences Peking University SIGMA Weather group State Key Laboratory for Space Weather Center for Space Science and Applied Research Chinese Academy of Sciences Institute of Geology and geophysics Chinese Academy of Sciences

Superhalo electrons appear to be continuously present in the interplane- tary medium, even during very quiet times, with a power-law spectrum at energies above ～2 keV. Here we numerically investigate the generation of superhalo electrons by magnetic reconnection in the solar wind source region, using magnetohydrody- namics and test particle simulations for both single X-line reconnection and multiple X-line reconnection. We find that the direct current electric field, produced in the mag- netic reconnection region, can accelerate electrons from an initial thermal energy of T ～105 K up to hundreds of keV. After acceleration, some of the accelerated elec- trons, together with the nascent solar wind flow driven by the reconnection, propagate upwards along the newly-opened magnetic field lines into interplanetary space, while the rest move downwards into the lower atmosphere. Similar to the observed superhalo electrons at 1 AU, the flux of upward-traveling accelerated electrons versus energy dis- plays a power-law distribution at ～ 2-100 keV, f（E）～ E^-δ, with a 6 of ～1.5 - 2.4. For single （multiple） X-line reconnection, the spectrum becomes harder （softer） as the anomalous resistivity parameter a （uniform resistivity η） increases. These modeling results suggest that the acceleration in the solar wind source region may contribute to superhalo electrons.

关键词： acceleration of particles -- methods:numerical -- Sun:particle emission-- (Sun:) solar wind -- Sun: transition region

The influence of mining factors on seismic activity during longwall mining of a coal seam

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International Journal of Mining Science and Technology 2021年第3期31卷 429-437页

作者： Łukasz Wojtecki Joanna Kurzeja Małgorzata Knopik Department of Geology and geophysics Central Mining Institute40-166 KatowicePoland Polish Mining group 40-039 KatowicePoland

In this article an attempt to determine the influence of mining factors on the seismic activity during the longwall mining of the upper layer of coal seam no.405/2 in one of the Polish hard coal mines in the Upper Silesian Coal Basin was *** longwall panels were mined in analogous geological conditions and based on the same mining system and ***,there was significant difference with regards to the mining factors,which was reflected in the observed seismic *** tools used in mining seismology were applied to illustrate the aforementioned influence of mining factors,*** frequency-energy distribution,the frequency-magnitude distribution,the 2 D distribution of released seismic energy,the relationship between released seismic energy and the volume of mined coal,the Benioff strain release,and the Gutenberg-Richter(GR)b coefficient distribution(b is the proportion between high and low energy tremors).Concerning the Benioff strain release,a new solution,based on the slope of a fitted line in a moving time window,is proposed.

关键词： Underground coal mining Induced seismicity Seismic statistics Benioff strain release

In vitro assessment of the synergism between extracts of Cocos nucifera husk and some standard antibiotics

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Asian Pacific Journal of Tropical Biomedicine 2017年第4期7卷 306-313页

作者： Taiwo Adesola Akinyele Etinosa Ogbomoede Igbinosa David Ayinde Akinpelu Anthony Ifeanyin Okoh SAMRC Microbial Water Quality Monitoring Centre University of Fort Hare applied and environmental Microbiology Research group Department of Biochemistry and MicrobiologyUniversity of Fort Hare

Objective: To evaluate the interactions between the crude extracts of Cocos nucifera(***) and six front line antibiotics(ampicillin sodium salt, penicillin G sodium,amoxicillin, chloramphenicol, ciprofloxacin and tetracycline hydrochloride), against some bacterial pathogens linked with human ***: The pulverized husk of *** was dissolved in 95% n-hexane and extracted using Soxhlet extraction method and sterile distilled water(aqueous).The antibacterial susceptibility of the crude extracts of *** was tested against environmental and clinical strains(6) obtained from the South African Bureau of Standards(SABS), Vibrio(6) and Listeria pathogens(6).The agar-well diffusion method was used for screening the extracts for their antibacterial *** minimum inhibitory concentration and minimum bactericidal concentration of the extracts were ***-kill assay was used to evaluate bactericidal and/or bacteriostatic *** synergistic effect of the crude extracts and antibiotics was assessed and evaluated by adopting the checkerboard ***: With the time-kill assay, the highest bactericidal activity was observed on Vibrio fluvialis EL041 with a-5.6 ± 0.2 log_(10)CFU/mL decrease in cell density as a result of the combination of the extracts and chloramphenicol at two-fold minimum inhibitory *** using the time-kill assay constituted about 72%, while indifference constituted about 28%.The checkerboard method revealed synergistic interaction in 67% of the combinations, and indifference in 33%.There was no specificity in the observed synergy to a particular class of ***: This investigation suggests the crude extracts of *** to be a potential broad spectrum antimicrobial ***, further study is needed to isolate the pure compounds from these crude extracts.

关键词： Antibacterial Inhibition zone Synergism Indifference Antibiotics Time-kill assay

Crustal reworking and orogenic styles inferred from zircon Hf isotopes:Proterozoic examples from the North Atlantic region

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Geoscience Frontiers 2019年第2期10卷 417-424页

作者： C.J.Spencer C.L.Kirkland A.R.Prave R.A.Strachan V.Pease Earth Dynamics Research group The Institute of Geoscience Research (TIGeR)Department of Applied GeologyCurtin University Centre for Exploration Targeting d Curtin Node Department of Applied GeologyCurtin University Department of Earth and environmental Sciences University of St Andrews School of Earth and environmental Sciences University of Portsmouth Department of Geological Sciences Stockholm University

Zircon Hf evolutionary patterns are powerful tools to investiage magma petrogenesis and crustal evolution. The ^(176)Hf/^(177)Hf isotopic signature of a rock is particularly informative and can be used to derive an estimation of the time when mantle extraction and diagnose closed system reworking where successive samples through time define an Hf evolution array dependant on the source Lu/Hf ratio. However, many magmatic events require new mantle addition as the thermal impetus for melting pre-existing crust. In this situation, rather than simply reflecting reworking, the isotopic signature indicates mixing with contributions from both reworked crust and new radiogenic input. Different geodynamic settings have different propensities for either reworking or addition of new mantle-derived magma. Hence, Hf-time trends carry within them a record, albeit cryptic, of the evolving geodynamic environment as different tectonic configurations recycle and add new crust at different rates, magnitudes, and from different sources. As an example of the difference in apparent Hf evolution slopes, we present Hf-time compilations from three geographically distinct Meso-to Neoproterozoic orogenic belts in the North Atlantic Region whose geodynamic configurations remain a subject of debate. We use the εHf/Ma trajectory to assist in understanding their evolution. The εHf/Ma trajectory of the Sveconorwegian Orogen corresponds to a ^(176)Lu/^(177) Hf ratio of 0.012, which implies a process driven primarily by reworking of preexisting crust that is balanced with input from the depleted mantle resulting in a relatively shallowεHf/Ma slope. The Valhalla Orogen reveals a similar comparatively shallow εHf/Ma path. In stark contrast to these patterns is the steep εHf/Ma trajectory of the Grenville Orogen that requires a mixing process involving a greater contribution of old crust of at least ～ 1.8 Ga age. The degree of reworking required to produce the εHf/Ma trend of the Grenville Orogen is co

关键词： Zircon Hf Crustal evolution Grenville Sveconorwegian Valhalla

A DFT-based Quantum Theoretic QSAR Study of Nitrobenzenes' Toxicity to Tetrahymena Pyriformis

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Chinese Journal of Structural Chemistry 2010年第1期29卷 86-92页

作者：顾云兰陶建清费正皓张根成 Jiangsu Provincial Key Laboratory of Coastal Wetland Bioresources and environmental Protection Institute of Applied Chemistry and Environmental EngineeringYancheng Teachers University

In this study,DFT-B3LYP level of theory with the 6-311G basis set was used to calculate a set of molecular descriptors of 36 *** structure-activity relationship（QSAR） models of the toxicity（pIGC50） of 36 nitrobenzenes were established using some of the following calculated descriptors：HOMO energy（EHOMO）,LUMO energy（ELUMO）,the difference between LUMO and HOMO energy values（ΔE=ELUMO–EHOMO）,average polarizability（P）,dipole moment（μ）,molecular volume（V） and the charge of nitro group（Q-NO2）.The QSAR models obtained by employing stepwise multiple regression techniques are aimed at correlating the structures with their reported experimental toxicity values. Among the models presented in this study, statistically the most significant one is a two-parameter linear equation with the correlation coefficient （R2） of 0.896 and cross-validated correlation coefficient （R2cv） of 0.878. To further validate the predictive ability of the resulting model, external validation was carried out with R2~xt and Q^2,ext values of 0.894, 0.900, 0.909, 0.874, 0.885 and 0.903, respectively. This study also reconstructed the obtained models using AMl-based calculated descriptors to demonstrate the superiority of DFT over AM1 for quantum calculations of mechanical descriptors. The results were discussed in the light of the main factors that influence the toxicity of nitrobenznenes.

关键词： nitrobenzenes toxicity DFT QSAR

Identification of Hydrocarbon Potential of Talhar Shale: Member of Lower Goru Formation Using Well Logs Derived Parameters, Southern Lower Indus Basin, Pakistan

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Journal of Earth Science 2018年第3期29卷 587-593页

作者： Muhsan Ehsan Hanming Gu Malik Muhammad Akhtar Saiq Shakeel Abbasi Zaheen Ullah Institute of geophysics and Geomatics China University of Geosciences Department of Earth and environmental Sciences Bahria University Islamabad School of environmental Studies China University of Geosciences Faculty of Earth Resources China University of Geosciences

Using well logs data only, the evaluation of shale gas hydrocarbon potential of Talhar Shale Member of Lower Goru Formation has been a challenge in Southern Lower Indus Basin in Pakistan. Well logs data analysis is helpful to evaluate the gas potential of source shale rocks. We introduced and applied empirical and graphical method to fulfil this task and derived geochemical parameters from well logs data. The method mentioned is cheap and fast. Talhar Shale has kerogen type Ⅲ and type Ⅱ which are montmorillonite clay and have potential to produce oil and gas. Talhar Shale has better sorption property. Empirical formulas are used to derive parameters, using well logs of porosity, density and uranium. Porosity and volume of kerogen, calculated from density log, give average values of 11.8% and 11.4%. Average value of level of maturity index （LMI） derived from log is 0.54, which indicates that it is at the early stage of maturity. Vitrinite reflectance is between 0.5%-0.55% as calculated by graphical method and empirical formula. Talhar Shale is at onset of oil generation, with main products of oil and gas. It is a good potential source in the study area.

关键词： Talhar Shale kerogen type sorption property thermal maturity vitrinite reflectance(Ro) Southern Lower Indus Basin.