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Detection of CO2 and O2 by iron loaded LTL zeolite films

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Frontiers of Chemical Science and Engineering 2018年第1期12卷 94-102页

作者： Veselina Georgieva Richard Retoux Valerie Ruaux Valentin Valtchev Svetlana Mintova laboratoire Catalyse et Spectrochimie (LCS) ENSICAEN CNRS Normandy University 14000 Caen France laboratoire de Cristallographie et Sciences des Matériaux (CRISMAT) ENSICAEN CNRS Normandy University 14000 Caen France

Detection of oxygen and carbon dioxide is important in the field of chemical and biosensors for atmosphere and biosystem monitoring and fermentation processes. The present study reports on the preparation of zeolite films doped with iron nanoparticles for detection of CO2 and O2 in gas phase. Pure nanosized LTL type zeolite with monomodal particle size distribution loaded with iron （Fe-LTL） was prepared under hydrothermal condition from colloidal precursor suspensions. The zeolite was loaded with iron to different levels by ion exchange. The Fe-LTL suspensions were used for preparation of thin films on silicon wafers via spin coating method. The reduction of the iron in the zeolite films was carried out under H2 flow （50% H2 in Ar） at 300 ℃. The presence of iron nanoparticles is proved by in situ ultra-violet-visible spectroscopy. The properties of the films including surface roughness, thickness, porosity, and mechanical stability were studied. In addition, the loading and distribution of iron in the zeolite films were investigated. The Fe-LTL zeolite films were used to detect O2 and CO2 in a concentration dependent mode, followed by IR spectroscopy. The changes in the IR bands at 855 and 642 cm^-1 （Fe O-H and Fe-O bending vibrations） and at 2363 and 2333 cm^-1 （CO2 asymmetric stretching） corresponding to the presence of O2 and CO2, respectively, were evaluated. The response to O2 and CO2 was instant, which was attributed to great accessibility of the iron in the nanosized zeolite crystals. The saturation of the Fe-LTL films with CO2 and O2 at each concentration was reached within less than a minute. The Fe-LTL films detected both oxygen and carbon dioxide in contrast, to the pure LTL zeolite film.

关键词： zeolite films detection of CO2 and O2 adsorption

Ductile deformation within Upper Himalaya Crystalline Sequence and geological implications,in Nyalam area,Southern Tibet

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Chinese Science Bulletin 2012年第26期57卷 3469-3481页

作者： LIU XiaoBing LIU XiaoHan LELOUP P.H. MAHEO G. PAQUetTE J.L. ZHANG XinGang ZHOU XueJun Key Laboratory of Continental Collision and Plateau UpliftInstitute of Tibetan Plateau ResearchChinese Academy of SciencesBeijing 100085China laboratoire des sciences de la terre de Lyon TerrePlanktesEnvironementCNRS UMR 5276Universitd Lyonl-ENS LyonVilleurbanne69622France Graduate University of Chinese Academy of Scienees Beijing 100049China laboratoire magmas et volcans CNRS UMR 6524Universite Blaise PascalClermont-Ferrand63038France

The South Tibet Detachment System(STDS) is a flat normal fault that separates the Upper Himalaya Crystalline Sequence(UHCS) below from the Tethyan Sedimentary Sequence(TSS) *** of deformations related to the STDS is critical to understand the mechanism and evolution of the Himalaya collision *** Nyalam detachment(ND)(～86°E) locates in the middle portion of STDS(81°-89°E).Dating of deformed leucocratic dykes that are most probably syntectonic at different depth beneath the ND,allow us to constrain the timing of deformation.(1) Dyke T11N37 located ～3500 m structurally below the ND emplaced at 27.4± 0.2 Ma;(2) Dyke T11N32 located ～1400 m structurally below the ND emplaced at 22.0±0.3 Ma;(3) T11N25 located within the top to the north STD shear zone,～150 m structurally below the ND,emplaced at 17.1±0.2 *** ND footwall cooling history and T11N25 deformation temperature,we indicate a probable onset of top to the north deformation at ～16 Ma at this *** results show an upward younging of the probable timing of onset of the deformation at different structural distance below the *** then propose a new model for deformation migration below the ND with deformation starting by pure shear deformation at depth prior to ～27.5 Ma that migrates upward at a rate of ～ 0.3 mm/a until ～18 Ma when deformation switches to top to the north shearing in the South Tibet Detachment shear zone(STDsz).As deformation on the ND stops at 14-13 Ma this would imply that significant top to the North motion would be limited to less than 5 Ma and would jeopardize the importance of lower channel flow.

关键词：喜马拉雅碰撞带塑性变形聂拉木地区西藏南部地质意义序列结晶藏南拆离系

Complex dynamics of an archetypal self-excited SD oscillator driven by moving belt friction

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Chinese Physics B 2016年第1期25卷 480-488页

作者：李志新曹庆杰 Léger Alain School of Astronautics Harbin Institute of Technology laboratoire de Mécanique et d'Acoustique CNRS

We propose an archetypal self-excited system driven by moving belt friction, which is constructed with the smooth and discontinuous （SD） oscillator proposed by the Cao et al. and the classical moving belt. The moving belt friction is modeled as the Coulomb friction to formulate the mathematical model of the proposed self-excited SD oscillator. The equilibrium states of the unperturbed system are obtained to show the complex equilibrium bifurcations. Phase portraits are depicted to present the hyperbolic structure transition, the multiple stick regions, and the friction-induced asymmetry phenomena. The numerical simulations are carried out to demonstrate the friction-induced vibration of multiple stick-slip phenomena and the stick-slip chaos in the perturbed self-excited system. The results presented here provide an opportunity for us to get insight into the mechanism of the complex friction-induced nonlinear dynamics in mechanical engineering and geography.

关键词： self-excited smooth and discontinuous (SD) oscillator multiple stick regions friction-inducedasymmetry stick-slip chaos

Anomalous elasticity of talc at high pressures:Implications for subduction systems

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Geoscience Frontiers 2022年第4期13卷 34-47页

作者： Ye Peng Mainak Mookherjee Andreas Hermann Geeth Manthilake David Mainprice Earth Materials Laboratory Department of EarthOceanand Atmospheric SciencesFlorida State UniversityTallahasseeFL 32306USA Centre for Science at Extreme Conditions and SUPA School of Physics and AstronomyThe University of EdinburghEdinburgh EH93FDUK laboratoire magmas et volcans cnrs IRDOPGCUniversitéClermont Auvergne63000 Clermont-FerrandFrance Geosciences Montpellier UMR CNRS 5243Universitéde MontpellierMontpellier 34095France

Talc is a layered hydrous silicate mineral that plays a vital role in transporting water into Earth’s interior and is crucial for explaining geophysical observations in subduction zone *** this study,we explored the structure,equation of state,and elasticity of both triclinic and monoclinic talc under high pressures up to 18 GPa using first principles simulations based on density functional theory corrected for dispersive *** results indicate that principal components of the full elastic constant tensor C_(11) and C_(22),shear components C_(66),and several off-diagonal components show anomalous pressure *** non-monotonic pressure dependence of elastic constant components is likely related to the structural changes and is often manifested in a polytypic transition from a low-pressure polytype talc-I to a high-pressure polytype talc-Ⅱ.The polytypic transition of talc occurs at pressures within its thermodynamic ***,the bulk and shear elastic moduli show no anomalous *** study also shows that talc has low velocity,extremely high anisotropy,and anomalously high V_(P)/V_(S) ratio,thus making it a potential candidate mineral phase that could readily explain unusually high V_(P)/V_(S) ratio and large shear wave splitting delays as observed from seismological studies in many subduction systems.

关键词： Talc Elasticity Seismic anisotropy Hydrous minerals Subduction zone

Citric Acid-Enhanced Electroremediation of Toxic Metal-Contaminated Dredged Sediments： Effect of Open/Closed Orifice Condition, Electric Potential and Surfactant

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Pedosphere 2018年第1期28卷 35-43页

作者： Yue SONG Ahmed BENAMAR Salim MEZAZIGH Huaqing WANG laboratoire Ondes et Milieux Complexes UMR CNRS 6294 Universite du Havre 76600 Le Havre France laboratoire Morphodynamique Continentale et Cotiere UMR CNRS 6143 Universite de Caen 14000 Caen France

Citric acid(CA), a widely used eco-friendly electrolyte, can be employed as an agent for enhancing toxic metal(TM) removal from contaminated dredged sediment using electrokinetic(EK) technology. In this study, dredged harbor sediments co-contaminated by TMs were subjected to enhanced EK treatment using a mixture of chelating agent(CA) and surfactant as an additive in the processing fluids. Several control conditions that may influence the efficiency of TM removal were tested, including open/closed sediment chamber orifices, electric potential gradients(0.5, 1.0, and 1.5 V cm^(-1)), and electrolyte surfactant. Tween 20(4 mmol L-1) was used as a surfactant within the electrolyte to investigate the extent of TM removal in sediment with high organic matter content. The results showed that an open orifice led to a greater electro-osmotic flow(EOF) with moderate TM removal. In contrast, a closed orifice with a nonionic surfactant electrolyte allowed the highest removal of TMs from the matrix. Moreover, increasing the electric potential gradient led to a higher EOF under the open orifice condition, but no significant increase in TM removal was observed owing to a higher accumulation of TMs in the middle of the matrix, caused by the opposite direction of EOF and electro-migration of metal-citrate complexes.

关键词： electric potential electrokinetic remediation electro-migration electro-osmotic flow electro-osmotic permeability metal-citrate complex

Rotating instability in the vaneless diffuser of a radial flow pump

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Journal of Thermal Science 2008年第4期17卷 368-374页

作者： A.Dazin O.Coutier-Delgosha P.Dupont S.Coudert G.Caignaert G.Bois laboratoire de Mécanique de Lille(UMR cnrs 8107) Arts et Métiers ParisTech laboratoire de Mécanique de Lille Ecole Centrale de Lille laboratoire de Mécanique de Lille CNRS

The paper refers to the behavior of a vaneless diffuser of a radial flow pump in partial flow operating conditions. Some experimental data have been obtained using 2D/2C PIV and unsteady pressure measurements within the diffuser, in various operating conditions. The experimental results at the lower flow rate are compared with two-dimensional numerical calculations.

关键词： Vaneless diffuser Radial flow pump Instability Particle Image Velocimetry Pressure measurements 2D calculations.

Ar^+/Ar, O_2^+/O_2 and N_2^+/N_2 Elastic Momentum Collision Cross Sections: Calculation and Validation Using the Semi-Classical Model

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Plasma Science and Technology 2014年第6期16卷 588-592页

作者： Djilali BENYOUCEF Mohammed YOUSFI laboratoire Génie Electrique et Energies Renouvelables Chlef University Universitéde Toulouse LAPLACE UMR CNRS

The aim of this paper is to obtain relevant sets of collision cross sections of the parent ions in low pressure discharges in argon, oxygen, and nitrogen, i.e., Ar＋ in Ar, O2＋ in O2 and N2＋ in N2. These ion data are first discussed and then validated from comparisons between the calculated transport coefficients and those measured in the literature. The elastic momentum transfer collision cross sections are determined from a semi-classical approximation for the phase shift calculation based on a 12-6-4 inter-particle potential while ion transport coefficients are determined versus the reduced electric field from Monte Carlo simulations.

关键词： inter-particle interaction potentials phase shift JWKB (Jeffreys WentzelKramers Brillouin) momentum collision cross sections Monte Carlo simulation ion trans-port coefficient

Swarm Theory, Hydraulic Fracturing, and the Emergence of Natural Spacing within Dyke Swarms

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Acta Geologica Sinica(English Edition) 2016年第S1期90卷 141-142页

作者： Andrew P.BUNGER Thierry MENAND Alexander CRUDEN ZHANG Xi Henry HALLS Department of Civil and Environmental Engineering University of Pittsburgh Department of Chemical and Petroleum Engineering University of Pittsburgh laboratoire magmas et volcans Université Blaise Pascal–CNRS–IRD OPGC School of Geosciences Monash University CSIRO Energy Department of Chemical and Physical Sciences University of Toronto at Mississauga

Like all swarming behavior in Nature,the selforganization expressed by the emergence of a natural spacing among a swarm’s members should be considered its most fundamental characteristic,and grasping the

关键词： Swarm Theory Hydraulic Fracturing

The allometry of number of feathers in birds changes seasonally

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Chinese Birds 2015年第1期6卷 1-5页

作者： Anders Pape Mller laboratoire d’Ecologie Systématique et Evolution CNRS UMR 8079Université Paris-Sud

Background: Feathers are a defining feature of birds with multiple functions such as flight, insulation, protection against predation and signaling. Feathers are lost during the annual molt while the rate of such loss at other times of the year and its fitness consequences remain poorly ***: I used information on the number and the mass of feathers for 160 individuals belonging to 85 species of birds in general linear mixed models to analyze allometry of feathers and to investigate possible factors explaining variation in the number of feathers. A phylogenetic effect was assessed by quantifying the random effect of ***: The total mass of feathers increased isometrically with body mass, while the total number of feathers and the mean mass of feathers showed negative allometry. Negative allometry implied that small-sized species had relatively many small feathers. There was a negative association between the number of feathers and migration distance. The total number of feathers initially increased during fall and winter, consistent with individuals growing more feathers later during the year or with individuals with fewer feathers selectively disappearing from the population. In contrast, the number of feathers decreased from winter through spring and ***: These findings suggest that thermoregulation has affected the evolution of the number and the size of feathers, there is selection against feather loss, and that the number of feathers varies across seasons.

关键词： Feather loss Molt Number of feathers Predation Thermoregulation