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地学前缘 2009年第S1期16卷 217-218页

作者： Omar Saddiqi Fatima Zahra EL Haimer Hassan Ⅱ University CasablancaMoroccoFaculty of Sciences laboratoire géosciences Faculté des SciencesUniversite Hassan Ⅱ An Chock

This work is based on apatite fission-track analysis of samples(mostly granites)from the basement of the Cretaceous-Tertiary Phosphate and ganntour Plateaus, exposed in the Jebilet and Rehamna massifs (Western Meseta,... 详细信息

关键词： thermochronology fission track apatite exhumation Rehamna Jebilet Western Meseta Morocco

Effects of lime treatment on the microstructure and hydraulic conductivity of Héricourt clay

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Journal of Rock Mechanics and geotechnical Engineering 2014年第5期6卷 399-404页

作者： Thanh Danh Tran Yu-Jun Cui Anh Minh Tang Martine Audiguier Roger Cojean Mines ParisTech-Centre de géosciences FontainebleauFrance laboratoire Navier/CERMES Ecole des Ponts ParisTech6 et 8 Avenue Blaise Pascal77455 Marne-la-Vallée Cedex 2France Mines ParisTeche-Centre de géosciences FontainebleauFrance

This study aims at evidencing the effects of lime treatment on the microstructure and hydraulic conductivityof a compacted expansive clay, with emphasis put on the effect of lime hydration and *** this purpose, evolutions of hydraulic conductivity were investigated for both lime-treatedand untreated soil specimens over 7 d after full saturation of the specimens and their microstructureswere observed at the end. Note that for the treated specimen, dry clay powder was mixed with quicklimeprior to compaction in order to study the effect of lime hydration. It is observed that lime hydration andmodification did not affect the intra-aggregate pores but increased the inter-aggregates pores size. Thisincrease gave rise to an increase of hydraulic conductivity. More precisely, the hydraulic conductivity oflime-treated specimen increased progressively during the first 3 d of modification phase and stabilisedduring the next 4 d which correspond to a short period prior to the stabilisation phase. The microstructureobservation showed that stabilisation reactions took place after 7 d. Under the effect of stabilisation,a decreasing hydraulic conductivity can be expected in longer time due to the formation ofcementitious compounds. 2014 Institute of Rock and Soil Mechanics, Chinese Academy of Sciences. Production and hosting byElsevier B.V. All rights reserved.

关键词： Clays Lime hydration Hydraulic conductivity Microstructure Temperature effect

Orbits of Jacobi forms and theta relations

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Science China Mathematics 2025年

作者： Valery gritsenko Haowu Wang laboratoire Paul Painlevé Université de Lille International Laboratory for Mirror Symmetry and Automorphic Forms National Research University Higher School of Economics School of Mathematics and Statistics Wuhan University

Jacobi theta functions with rational characteristics can be viewed as vector-valued Jacobi *** relations usually correspond to different constructions of certain Jacobi forms. From this observation, we extract a new approach, which is called orbits of Jacobi forms, to produce identities on Jacobi theta *** approach not only provides simple proofs of many known theta relations but also produces a large number of new identities, which can be considered as generalizations of Riemann’s theta relations.

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Segmental closure of the Mongol-Okhotsk Ocean:Insight from detrital geochronology in the East Transbaikalia Basin

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geoscience Frontiers 2022年第1期13卷 15-27页

作者： Anastasia V.Arzhannikova Elena I.Demonterova Marc Jolivet Ekaterina A.Mikheeva Alexei V.Ivanov Sergey g.Arzhannikov Valentin B.Khubanov Vadim S.Kamenetsky Institute of the Earth’s Crust Russian Academy of SciencesSiberian BranchIrkutskRussia laboratoire géosciences Rennes CNRS-UMR6118Universitéde RennesRennesFrance geological Institute Russian Academy of SciencesSiberian BranchUlan-UdeRussia

The Late Paleozoic–Early Mesozoic Mongol-Okhotsk Ocean extended between the Siberian and Amur–North China *** timing and modalities of the oceanic closure are widely *** is largely accepted that the ocean closed in a scissor-like manner from southwest to northeast(in modern coordinates),though the timing of this process remains *** studies have shown that both western(West Transbaikalia)and eastern(Dzhagda)parts of the ocean closed almost simultaneously at the Early–Middle Jurassic ***,little information on the key central part of the oceanic suture zone is *** performed U-Pb(LA-ICP-MS)dating of detrital zircon from wellcharacterized stratigraphic sections of the central part of the Mongol-Okhotsk suture *** include the initial marine and final continental sequences of the East Transbaikalia Basin,deposited on the northern Argun-Idemeg terrane *** provide new stratigraphic ages for the marine and continental *** revised chronostratigraphy allows assigning an age of~165–155 Ma,to the collisionrelated flexure of the northern Argun-Idemeg terrane and the development of a peripheral foreland *** collisional process took place 5 to10 million years later than in the western and eastern parts of the *** demonstrate that the northern Argun-Idemeg terrane was the last block to collide with the Siberian continent,challenging the widely supported scissor-like model of closure of the MongolOkhotsk *** segments of the ocean closed independently,depending on the initial shape of the paleo continental margins.

关键词： Detrital zircon U-Pb geochronology Mongol-Okhotsk collision East Transbaikalian Basin

Chemical Availability of Cd, Pb and Zn in Anthropogenically Polluted Soil: Assessing the geochemical Reactivity and Oral Bioaccessibility

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Pedosphere 2017年第3期27卷 616-629页

作者： Christophe WATERLOT Francis DOUAY Aurélie PELFRENE Yncréa Hauts-de-France Laboratoire Génie Civil et géo Environnement (LGCgE)

The most recent in vitro tests used to determine metal bioaccessiblility are generally time-consuming and expensive. This study aimed at determining potential relationships between the concentrations of metals extracted using single-extraction methods and the concentrations of bioaccessible metals assessed by a harmonised in vitro test, the Unified BARgE Method （UBM）. A total number of 27 soil samples were collected from kitchen gardens and lawns with various physicochemical parameters and contamination levels. Significant relationships were obtained between Cd, Pb and Zn extracted in gastric and gastrointestinal phases and using single extractions. The best relationhips were established using acetic and citric acids for Cd, whereas for Pb, citric acid and ethylenedi- aminetetraacetic acid （EDTA） were identified as the best extractants. These relationships were improved by means of a linear multiple regression with a downward stepwise procedure involving agronomic parameters （soil cation exchange capacity and assimilated P）. This method highlighted the fact that the cation exchange capacity and P contents in soils were the two main parameters that controlled the human bioaccessibility of Cd, Pb and Zn in the gastric phase. Besides, the metal concentrations extracted with the acetic and citric acids correlated well with the metal concentrations in the gastric and gastrointestinal phases, suggesting that the bioaceessible metals were mainly in a soluble form, weakly bound to the organic matter and associated with the carbonates and the Fe and Mn oxides/hydroxides in soils.

关键词： gastric phase gastrointestinal phase linear multiple regression single extractant urban soil

Taxonomic and metabolic shifts in the Coorong bacterial metagenome driven by salinity and external inputs

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Journal of Oceanology and Limnology 2018年第6期36卷 2033-2049页

作者： Kelly NEWTON Thomas C.JEFFRIES Renee J.SMITH Justin R.SEYMOUR Laurent SEURONT James g.MITCHELL School of Biological Sciences Flinders University School of Science and Health Western Sydney University Flinders Centre for Innovation in Cancer Flinders University Climate Change Cluster University of Technology Sydney Centre National de la Recherche Scientifi que Laboratoire d'Océanologie et de Géosciences

The Coorong estuary lies at the terminus of Australia's largest river system, the Murray-Darling; both are strongly influenced by human activities; including farming and extensive flow modification. Metagenomic approaches were used to determine the planktonic bacterial community composition and potential metabolic function at two extremes in the Coorong, the river mouth which exhibits marine-like salinity, and the hypersaline upper-reaches of the estuary. Significant shifts in taxa and metabolic function were seen between the two sites. The river mouth exhibited an increase in abundance of R hodobacteriaceae and Alteromonadaceae; families readily able to adapt to change in nutrient conditions; and the potentially pathogenic families B rucellaceae, Enterobacteriaceae and Vibrionaceae. Metabolisms over-represented include motility and chemotaxis, RNA metabolism and membrane transport, all of which are involved in actively searching for and obtaining nutrients. Also over-represented were metabolisms involved in population succession and stress response. An over-representation of taxa and metabolisms indicative of environmental change is reflective of anthropogenically af fected riverine input. In the hypersaline upper reaches of the estuary, the halophilic family Ectothiorhodospiraceae was over-represented, as were the families Flavobacteriaceae, Cytophagaceae and Nocardioidaceae, members of which are able to survive over a wide salinity range. Metabolisms over-represented here were reflective of increased bacterial growth, characteristic of hypersaline environments, and included DNA metabolism, nucleotide and nucleoside synthesis and cell cycle. Coorong metagenomes clustered taxonomically and metabolically with other planktonic metagenomes, but remained an outlier of this group with only 71% and 84% similarity, respectively. This indicates that the Coorong exhibits a unique planktonic bacterial community that is influenced by riverine input at the river mouth and sali

关键词： hypersaline estuary bacteria taxonomy metabolic potential

High resolution facies architecture and digital outcrop modeling of the Sandakan formation sandstone reservoir, Borneo:Implications for reservoir characterization and flow simulation

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geoscience Frontiers 2019年第3期10卷 957-971页

作者： Numair A.Siddiqui Mu.Ramkumar Abdul Hadi A.Rahman Manoj J.Mathew M.Santosh Chow W.Sum David Menier Department of Petroleum geosciences Universiti Teknologi PETRONAS Department of geology Periyar University Institute of Oceanography and Environment Universiti Malaysia Terengganu Department of Earth Sciences University of Adelaide School of Earth Sciences and Resources China University of Geosciences Beijing laboratoire géosciences Océan UMR CNRS 6538Campus de Tohannic

Advances in photogrammetry have eased the acquisition of high-resolution digital information from outcrops, enabling faster, non-destructive data capturing and improved reservoir modeling. geocellular models for flow dynamics with in the virtual outcrop in siliciclastic deposits at different sets of sandstone facies architecture remain, however, a challenge. Digital maps of bedding, lithological contrast, spatial-temporal variations of bedding and permeability characteristics make it more easy to understand flow tortuosity in a particular architecture. An ability to precisely model these properties can improve reservoir characterization and flow modeling at different scales. Here we demonstrate the construction of realistic 2 D sandstone facies based models for a pragmatic simulation of flow dynamics using a combination of digital point clouds dataset acquired from LiDAR and field investigation of the Sandakan Formation, Sabah, ***, we present methods for enhancing the accuracy of outcrop digital datasets for producing high resolution flow simulation. A well-exposed outcrop from the Sandakan Formation, Sabah, northwest Borneo having a lateral extent of 750 m was chosen in order to implement our research approach. Sandstone facies and its connectivity are well constrained by outcrop observations, data from air-permeability measurements, bilinear interpolation of permeability, grid construction and water vector analysis for flow *** proportions were then enumerated in terms of static digital outcrop model(DOM) and facies model based on sandstone facies bedding characteristics. Flow simulation of water vector analysis through each of the four sandstone facies types show persistent spatial correlation of permeability that align with either cross-bedded orientation or straight with more dispersion high quality sandstone(porosity 21.25%-41.2%and permeability 1265.20-5986.25 mD) and moderate quality sandstone(porosity 10.44%-28.75% and permeabili

关键词： Siliciclastic sandstone facies Connectivity Heterogeneity Digital outcrop model Flow dynamics

Electrical model parameters identification of radiofrequency discharge in argon through 1D3V/PIC-MC model

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Plasma Science and Technology 2018年第9期20卷 106-113页

作者： Mohamed MOSTAFAOUI Djilali BENYOUCEF laboratoire génie Electrique et Energies Renouvelables Université Hassiba Benbouali de Chlef

This work represents a contribution to the modeling of a radiofrequency（RF） discharge in argon at low pressure（from 25 to 200 mTorr）.It is started by the validation of the collision cross sections used in the particle model through a comparison between the transport coefficients calculated by these data and the measurements of the transport coefficients already exist in the literature,the particle model is also validated by a comparison between the calculated plasma density and that measured in the *** electrical model proposed in this work consists of replacing the RF discharge by a passive circuit（resistance in series with a capacitor）,where the resistance represents the plasma medium and the obstruction of the passage of the electronic current,and the capacitor represents the sheaths and the appearance of the displacement current in these *** parameters of the electrical model are obtained through particle *** electrical model presented accurately reproduces the current of the discharge,but without considering the phenomenon of *** total harmonic distortion rate follows the variation of the plasma density;its maximum value is 5.75% at 100 mTorr.

关键词： electrical model least square method particle model radiofrequency discharge static parameters identification

geochemical tracing and modeling of surface and deep water–rock interactions in elementary granitic watersheds(Strengbach and Ringelbach CZOs, France)

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Acta geochimica 2017年第3期36卷 363-366页

作者： F.Chabaux D.Viville Y.Lucas J.Ackerer C.Ranchoux C.Bosia M.C.Pierret T.Labasque L.Aquilina R.Wyns C.Lerouge C.Dezaye P.Négreol laboratoire D'Hydrologie et de géochimie de Strasbourg (LHygeS) CNRS Université de Strasbourg 1 Rue Blessig 67084 Strasbourg Cedex France CNRS Géosciences Rennes UMR 6118 Université de Rennesl Campus de Beaulieu 35042 Rennes Cedex France BRgM 3 Avenue Claude Guillemin 45060 Orléans France

From the study of the Strengbach and Ringelbach watersheds we propose to illustrate the interest of combining the geochemical tracing and geochemical modeling approaches on surface and deep borehole waters,to decipher the diversity of the water flow and the associated water–rock interactions in such elementary mountainous catchments. The results point to a clear geochemical typology of waters depending on the water circulations(deep vs. hypodermic) within the substratum.

关键词： Weathering Water pathways U activity ratios Sr isotope ratios Anthropogenic gases(CFC,SF6) CZO

An executive review of sludge pretreatment by sonication

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Journal of Environmental Sciences 2015年第11期27卷 139-153页

作者： Ngoc Tuan Le Carine Julcour-Lebigue Henri Delmas University of Science Vietnam National University Université de Toulouse Laboratoire de Génie Chimique

Ultrasonication（US）, which creates hydro-mechanical shear forces in cavitation, is an advanced technology in sludge pretreatment. However, there are many factors affecting the efficacy of cavitation and ultrasonication disintegration of sludge as a *** objective of this work is to present an extensive review of evaluation approaches of sludge US pretreatment efficiency. Besides, optimization methodologies of related parameters,the differences of optimum values and the similarities of affecting trends on cavitation and sludge pretreatment efficiency were specifically pointed out, including ambient conditions,ultrasonic properties, and sludge characteristics. The research is a prerequisite for optimization of sludge US pretreatment efficiency in lab-scale and practical application. There is not-yet a comprehensive method to evaluate the efficiency of sludge US pretreatment, but some main parameters commonly used for this purpose are degree of sludge disintegration, proteins,particle size reduction, etc. Regarding US parameters, power input PUS, intensity IUS, and frequency FSseem to have significant effects. However, the magnitude of the effect of PUSand probe size in terms of IUShas not been clearly detailed. Investigating very low FSseems interesting but has not yet been taken into consideration. In addition, static pressure effect has been marginally studied only and investigation on the effect of pH prior to US process has been restricted. Their effects therefore should be varied separately and simultaneously with other related parameters, i.e. process conditions, ultrasonic properties, and sludge characteristics, to optimize sludge US pretreatment process.

关键词： Ultrasonic pretreatment Waste activated sludge Sludge disintegration Acoustic frequency Intensity effect Pressure effect