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Shape Controllable Preparation of Submicronic Cadmium Tetrazole-Based Metal-Organic Frameworks via Solvothermal or Microwave-Assisted Methods and Their Photocatalytic Studies

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Chinese Journal of Chemistry 2017年第2期35卷 209-216页

作者： Arti Chouhan Guillaume Pilet Stephane Daniele Ashutosh Pandey Department of Chemistry MNNIT Allahabad Allahabad 211004 India LMI UMR CNRS 5615 University Claude Bernard-Lyon 1 69622 Villeurbanne cedex France IRCELYON UMR CNRS 5256 University Claude Bernard-Lyon 1 69626 Villeurbanne cedex France

The paper describes the experiments conducted to create shape controllable preparations of submicronic cad- mium tetrazole-based MOFs. In order to prepare the submicron sized blocks and tubes of bis[5-（2-pyridyltetrazo- lato）]diaquacadmium（II） [（2-PTZ）2Cd（H20）2] MOFs both solvothermal and microwave augmented reaction proce- dures have been followed. Cadmium nitrate tetrahydrate, cyanopyridine and sodium azide were used as reactants in both the conditions without any surfactants or modulators. Subsequently, IR spectroscopy and single-crystal X-ray crystallographic studies were performed on the prepared MOFs. Examinations using scanning electron microscopy and X-ray powder diffraction of the products made by the microwave method showed formation of bundles of reg- ular submicrotubes, as opposed to the submicron-sized irregular blocks of the Cd-MOF obtained through the sol- vothermal method. The fluorescence peak of the sub-microtube MOF was found at 460 nm while the irregu- lar-blocks emitted at 442 nm indicating a red shift for the former. In addition, the relative intensity of the peak at 460 nm was higher in the former, indicating a decrease in the crystallite size. Band gaps of the MOFs calculated by using the Tauc plots were 2.87 and 2.73 eV, respectively. Their photocatalytic performances using methylene blue under UV-vis irradiation have been investigated.

关键词： cadmium microwave synthesis solvothermal synthesis submicrotube photocatalysis

Water extraction kinetics of metals, arsenic and dissolved organic carbon from industrial contaminated poplar leaves

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Journal of Environmental Sciences 2013年第12期25卷 2451-2459页

作者： Muhammad Shahid Tiantian Xiong Maryse Castrec-Rouelle Tibo Leveque Camille Dumat Department of Environmental Sciences COMSATS Institute of Information Technology University of Toulouse INP-ENSATAv of Agrobiopole umr 5245 cnrs-INP-UPS EcoLab umr 7618 BioEmco UPMC-Paris 6

In industrial areas, tree leaves contaminated by metals and metalloids could constitute a secondary source of pollutants. In the present study, water extraction kinetics of inorganic elements （IE： Pb, Zn, Cd, As, Fe and Mn）, dissolved organic carbon, pH and biological activity were studied for industrial contaminated poplar leaves. Moreover, the distribution of the IE through the size fractions of the associated top soil was measured. High quantities ofMn, Zn and As and polysaccharides were released in the solution from the strongly contaminated leaves. The kinetic of release varied with time and metal type. The solution pH decreased while dissolved organic contents increased with time after 30 days. Therefore, these contaminated leaves could constitute a source of more available organic metals and metalloids than the initial inorganic process particles. However, the distribution of the IE through the size fractions of the top soil suggested that a great part of the released IE was adsorbed, reducing in consequence their transfers and bioavailability. It＇s concluded that mobility/boioavailability and speciation of metals and metalloids released from the decomposition of polluted tree leaves depends on soil characteristics, pollutant type and litter composition, with consequences for environmental risk assessment.

关键词： metals and metalloids dissolved organic carbon litter decomposition kinetics speciation water extraction

Surface morphology-optical properties relationship in thermochromic VO_(2) thin films obtained by air oxidation of vanadium nitride

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Journal of Materiomics 2021年第4期7卷 657-664页

作者： A.C.García-Wong D.Pilloud S.Bruyere D.Mangin S.Migot J.F.Pierson F.Capon Institut Jean Lamour(umr cnrs 7198) Universite de Lorraine54000NancyFrance

In this paper,vanadium nitride(VN)thin films have been deposited on Al substrates by reactive magnetron *** VO_(2) films have been obtained by air oxidation of VN samples performed at three temperatures(450,525 and 550℃)at various durations(lower than 50 min).X-ray diffraction and Raman spectrometry of the VN oxidized films indicate that VO_(2) and V2O5 are the only phases produced during the oxidation *** dioxide is the first oxide *** coexists with VN in a long period at 450℃ or suddenly disappears at 525 and 550℃.Whatever the temperature,V2O5 is exclusively detected after the total oxidation of *** oxide is detrimental to the thermochromic performance of *** emissivity-switching properties of the oxidized films were analyzed by infrared camera in the 7.5e13 mm *** comparison among all the samples exhibiting a thermochromic behavior shows that the maximum emissivity switch is independent of the oxidation temperature and the surface morphology of the *** results could open a new strategy in the investigation of VN oxidation as a method to obtain VO_(2),along with an insight into the correlation between surface morphology and optical properties.

关键词： Vanadium dioxide Vanadium nitride Thermochromism Optical properties Air oxidation

An efficient sensitivity analysis for energy performance of building envelope: A continuous derivative based approach

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Building Simulation 2021年第4期14卷 909-930页

作者： Ainagul Jumabekova Julien Berger Aurélie Foucquier umr 5271 cnrs LOCIEUniversity of Grenoble AlpesUniversity of Savoie Mont Blanc73000ChambéryFrance LaSIE La Rochelle UniversityCNRSUMR 735617000La RochelleFrance CEA LITENDTSINESUniversity of Grenoble AlpesF-38000GrenobleFrance

Within the framework of building energy assessment,this article proposes to use a derivative based sensitivity analysis of heat transfer models in a building ***,global and local,estimators are obtained at low computational cost,to evaluate the influence of the parameters on the model *** of these estimators values allows to reduce the number of model unknown parameters by excluding non-significant parameters.A comparison with variance and regression-based methods is carried out and the results highlight the satisfactory accuracy of the continuous-based ***,for the carried investigations the approach is 100 times faster compared to the variance-based methods.A case study applies the method to a real-world building *** sensitivity of the thermal loads to local or global variations of the wall thermal properties is ***,a case study of wall with window is analyzed.

关键词： heat transfer sensitivity analysis continuous derivative based approach parameter estimation problem DuFort-Frankel numerical scheme sensitivity coefficients

Acousto-optically driven lensless single-shot ultrafast optical imaging

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Light(Science & Applications) 2022年第4期11卷 628-643页

作者： Mohamed Touil Said Idlahcen Rezki Becheker Denis Lebrun Claude Roze Ammar Hideur Thomas Godin ORIA CNRS UMR6614-University de Rouen Normandie-INSA Rouen76800 Saint Etienne du RouvrayFrance

Driven by many applications in a wide span of scientifc fields,a myriad of advanced ultrafast imaging techniques have emerged in the last decade,featuring record-high imaging speeds above a trllion-frame-per-second with long sequence *** bringing remarkable insights into various ultrafast phenomena,their application out of a laboratory environment is however limited in most cases,either by the cost,complexity of the operation or by heavy data *** then report a versatile single-shot imaging technique combining sequentially timed lloptical mapping photography(STAMP)with acousto-optics programmable dispersive fhItering(AOPDF)and digital in-line holography(DIH).On the one hand,a high degree of simplicity is reached through the AOPDF,which enables full control over the acquisition parameters via an electrically driven phase and amplitude spectro-temporal tailoring of the imaging ***,contrary to most single-shot techniques,the frame rate,exposure time,and frame intensities can be independently adjusted in a wide range of pulse durations and chirp values without resorting to complex shaping stages,making the system remarkably agile and *** the other hand,the use of DIH,which does not require any reference beam,allows to achieve an even higher technical simplicity by allowing its lensless operation but also for reconstructing the object on a wide depth of field,contrary to classical techniques that only provide images in a single *** imaging speed of the system as well as its flexibility are demonstrated by visualizing ultrashort events on both the picosecond and nanosecond *** virtues and limitations as welll as the potential improvements of this on-demand ultrafast imaging method are critically discussed.

关键词： simplicity resort bringing

Quantitative Mapping of Transient Thermodynamic States in Ultrafast Laser Nanostructuring of Quartz

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Ultrafast Science 2024年第2期4卷 9-18页

作者： H.D.Nguyen A.Tsaturyan S.Sao Joao R.Dwivedi A.Melkonyan C.D’Amico E.Kachan J.P.Colombier G.Kermouche R.Stoian Laboratoire Hubert Curien UMR 5516 CNRSUniversite Jean Monnet42000 Saint EtienneFrance Laboratoire George Friedel UMR 5307 CNRSEcole des Mines de Saint Etienne42000 Saint EtienneFrance

Understanding material structural reaction to light is of utmost importance to advance processing resolution in ultrafast laser volume structuring into the *** thermodynamic pathways are required to quench energy transport in the most rapid manner and to confine the process to nanometer lengths,bypassing optical *** material dynamics under confinement,with in situ access to transient local temperature and density parameters,thus becomes key in understanding the *** report in situ reconstruction of thermodynamic states over the entire matter relaxation path in bulkα-quartz irradiated by ultrafast nondiffractive laser beams using time-resolved qualitative and quantitative optical phase *** dynamics indicate rapid spatially confined crystalline-to-amorphous transition to a hot dense fused silica *** exceeds 20%and the matrix temperature rises to more than 2,000 K in the first *** structural state relaxes in hundreds of *** dispersion and time design of the optical beam to picosecond durations increases the spatial confinement and triggers an extreme nanostructuring process based on nanocavitation that occurs within the amorphizing material,where the low-viscosity phase lowers the mechanical requirements for the *** feature scales of less than a tenth of the optical wavelength are obtained in the *** allows for structural and morphological nanoscale material features under 3D confinement that can engineer optical materials.

关键词： Quartz hundreds qualitative

SURFACE MODIFICATION OF MICROPOROUS POLYPROPYLENE MEMBRANES BY GRAFT POLYMERIZATION OF N,N-DIMETHYLAMINOETHYL METHACRYLATE

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Chinese Journal of Polymer Science 2004年第4期22卷 369-377页

作者：徐志康 Patrick Seta Institute of Polymer Science Zhejiang University Hangzhou 310027 China LMPM UMR 5635 CNRS 34293 Montpellier Cedex 05 France

Surface modification of microporous polypropylene hollow fiber membranes was performed by radical-induced graft polymerization of N,N-dimethylaminoethyl methacrylate (DMAEMA). The influences of temperature, monomer concentration and pre-adsorbed amount of benzoyl peroxide on grafting degree were studied respectively. It was found that the appropriate graft temperature was 75 'C, at which the grafting degree was the highest and the hydrolytic decomposition of DMAEMA the lowest. Scanning electron photomicrography and the average pore diameters of the modified membranes demonstrated that part of the micropores on the membrane surface was plugged by the grafted polyDMAEMA chains, especially at high grafting degree. Contact angle and water swelling experiments showed that a moderate grafting degree could improve the hydrophilicity of the membranes. In the range of 11.3%-12.0% grafting degree, the water swelling percentage reached its maximum (51.1%) and the contact angle reached its minimum (74 degrees). The bovine serum albumin (BSA) adsorption experiment indicated that the grafted polyDMAEMA had a dual effect on protein adsorption. At the first stage, the BSA adsorption decreased with increasing of DMAEMA grafting degree. As the interaction between BSA and polyDMAEMA on membrane surface increased, the BSA adsorption increased with increasing of DMAEMA grafting degree.

关键词： Polypropylene hollow fiber membrane N,N-Dimethylaminiethyl methacrylate Surface modification Graft polymerization BSA adsorption

Theoretical and numerical investigation of HF elastic wave propagation in two-dimensional periodic beam lattices

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Acta Mechanica Sinica 2013年第6期29卷 783-798页

作者： B.Tie B.Y.Tian D.Aubry Laboratory MSSMat(umr-cnrs 8579) Ecole Centrale ParisGrande Voie des Vignes92295 Chatenay-Malabry CedexFrance

The elastic wave propagation phenomena in two-dimensional periodic beam lattices are studied by using the Bloch wave transform. The numerical modeling is applied to the hexagonal and the rectangular beam lattices, in which, both the in-plane （with respect to the lattice plane） and out-of-plane waves are considered. The dispersion relations are obtained by calculating the Bloch eigenfrequencies and eigenmodes. The frequency bandgaps are observed and the influence of the elastic and geometric properties of the primitive cell on the bandgaps is studied. By analyzing the phase and the group velocities of the Bloch wave modes, the anisotropic behaviors and the dispersive characteristics of the hexagonal beam lattice with respect to the wave prop- agation are highlighted in high frequency domains. One im- portant result presented herein is the comparison between the first Bloch wave modes to the membrane and bend- ing/transverse shear wave modes of the classical equivalent homogenized orthotropic plate model of the hexagonal beam lattice. It is shown that, in low frequency ranges, the homog- enized plate model can correctly represent both the in-plane and out-of-plane dynamic behaviors of the beam lattice, its frequency validity domain can be precisely evaluated thanks to the Bloch modal analysis. As another important and original result, we have highlighted the existence of the retro- propagating Bloch wave modes with a negative group veloc- ity, and of the corresponding ＂retro-propagating＂ frequency bands.

关键词： Elastic wave propagation Periodic beam lattice Bloch wave theory Bandgaps Anisotropy Disper- sion relation

SYNCHRONIZED PATH FOLLOWING CONTROL OF MULTIPLE HOMOGENOUS UNDERACTUATED AUVS

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Journal of Systems Science & Complexity 2012年第1期25卷 71-89页

作者： Xianbo XIANG Chao LIU Lionel LAPIERRE Bruno JOUVENCEL School of Naval Architecture and Ocean Engineering Huazhong University of Science and Technology Department of Robotics LIRMM-CNRS-UMIIUMR 5506161 rue AdaMontpellier Cedex 534095France Department of Robotics LIRMM-CNRSUMR 5506161 rue AdaMontpellier Cedex 534095France

This paper addresses the problem of synchronized path following of multiple homogenous underaetuated autonomous underwater vehicles （AUVs）. The dedicated control laws are categorized into two envelopes： One is steering individual underwater vehicle to track along predefined path, and the other is ensuring tracked paths of multiple vehicles to be synchronized, by means of decentralized speed adaption under the constraints of multi-vehicle communication topology. With these two tasks formulation, geometric path following is built on Lyapunov theory and baekstepping techniques, while injecting helmsman behavior into classic individual path following control. Synchronization of path parameters are reached by using a mixture of tools from linear algebra, graph theory and nonlinear control theory. A simple but effective control design on direct inter-vehicle speed adaption with minimized communication variables, enables the multi-AUV systems to be synchronized and stabilized into an invariant manifold, and all speeds converge to desired assignments as a byproduct. Simulation results illustrate the performance of the synchronized path following control laws proposed.

关键词： Path following synchronization underactuated AUVs.