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Investigation of KTiOPO4 nanocrystals by means of second-harmonic light emission

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Chinese Optics Letters 2008年第1期6卷 64-67页

作者： Chunyuan Zhou Loc Le Xuan Abdallah Slablab Nicolas Sandeau Sophie Brasselet dominique Chauvat jean-Francois Roch Laboratoire de Photonique Quantique et Moléculaire ENS Cachan UMR CNRS 8537 61 avenue du President Wilson 94235 Cachan Cedex France

The finding of nonlinear nanometric-sized probes is of key importance for the development of nonlinear microscopy in physical as well as biological sciences. We isolate nonlinear KTiOPO4 nanocrystals and study them by second-harmonic generation microscopy （SHGM） and atomic force microscopy （AFM） independently. With both polarization analysis and defocused imaging of the emitted second harmonic field, we extract the Euler angles of the crystalline axes of a single nanocrystal. A balanced coherent optical homodyne detection shows the coherent nature of the nanocrystal nonlinear emission and allows a phase measurement of the emitted second-harmonic field. These features make the KTiOPO4 nanocrystal a good candidate for a vectorial probe of electromagnetic near fields.

关键词： KTiOPO4 谐波光发射物理学

Computational design for 4D printing of topology optimized multi-material active composites

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npj Computational Materials 2023年第1期9卷 2342-2350页

作者： Darshan Athinarayanarao Romaric Prod’hon dominique Chamoret H.Jerry Qi Mahdi Bodaghi jean-Claude André Frédéric Demoly ICB UMR 6303 CNRS Univ.Bourgogne Franche-ComtéUTBM90010 BelfortFrance The George W.Woodruff School of Mechanical Engineering Georgia Institute of TechnologyAtlantaGA 30332USA Department of Engineering School of Science and TechnologyNottingham Trent UniversityNottingham NG118NSUK LRGP UMR 7274 CNRS University of LorraineNancyFrance

Recent efforts on design for four-dimensional(4D)printing have considered the spatial arrangement of smart materials and energy *** development of multifunctional structures and their desired mechanical/actuation performances require tackling 4D printing from a multi-material design *** the materials distributions there is an opportunity to increase the spectrum of design concepts with computational *** main goal being to achieve the“best”distribution of material properties in a voxelized structure,a computational framework that consists of a finite element analysis-based evolutionary algorithm is *** fuses the advantages of optimizing both the materials distribution and material layout within a design space via topology optimization to solve the inverse design problem of finding an optimal design to achieve a target shape change by integrating void *** results demonstrate the efficacy of the proposed method in providing a highly capable tool for the design of 4D-printed active composites.

关键词： composites printing topology

Line-field confocal optical coherence tomography for three-dimensional skin imaging

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Frontiers of Optoelectronics 2020年第4期13卷 381-392页

作者： Jonas OGIEN Anthony DAURES Maxime CAZALAS jean-Luc perrot Arnaud DUBOIS DAMAE Medical Paris 75013.France CHU St-Etienne Service DermatologieSaint-Etienne 42055France Universite Paris-Saclay Institut d'Optique Graduate SchoolCNRSLaboratoire Charles FabryPalaiseau 91127France

This paper reports on the latest advances in line-field confocal optical cohere nee tomography(LC-OCT),a recently invented imaging technology that now allows the generation of either horizontal(x×y)section images at an adjustable depth or vertical(x×z)section images at an adjustable lateral position,as well as thre dimensional *** both two-dimensional imaging modes,images are acquired in real-time,with real-time control of the depth and lateral ***-dimensional(x×y×z)images are acquired from a stack of horizontal section *** device is in the form of a portable *** handle of the probe has a button and a scroll wheel allowing the user to control the imaging *** a supercontinuum laser as a broadband light source and a high numerical microscope objective,an isotropic spatial resolution of^1|im is *** field of view of the three-dimensional images is 1.2 mm×0.5 mm×0.5 mm(x×y×z).Images of skin tissues are presented to demonstrate the potential of the technology in dermatology.

关键词： optical coherence tomography(OCT) microscopy three-dimensional imaging dennatology

Microstructure and anisotropic swelling behaviour of compacted bentonite/sand mixture

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Journal of Rock Mechanics and Geotechnical Engineering 2014年第2期6卷 126-132页

作者： Simona Saba jean-dominique Barnichon Yu-Jun Cui Anh Minh Tang Pierre Delage Ecole des Ponts ParisTech Laboratoire Navier Institut de Radioprotection et de Surete Nucleaire(IRSN)

Pre-compacted elements （disks, tutus） of bentonite/sand mixture are candidate materials for sealing plugs of radioactive waste disposal. Choice of this material is mainly based on its swelling capacity allowing all gaps in the system to be sealed, and on its low permeability. When emplaced in the gallery, these elements will start to absorb water from the host rock and swell. Thereby, a swelling pressure will develop in the radial direction against the host rock and in the axial direction against the support structure. In this work, the swelling pressure of a small scale compacted disk of bentonite and sand was experimentally studied in both radial and axial directions. Different swelling kinetics were identified for different dry densities and along different directions. As a rule, the swelling pressure starts increasing quickly, reaches a peak value, decreases a little and finally stabilises. For some dry densities, higher peaks were observed in the radial direction than in the axial direction. The presence of peaks is related to the microstructure change and to the collapse of macro- pores. In parallel to the mechanical tests, microstructure investigation at the sample scale was conducted using microfocus X-ray computed tomography （BCT）. Image observation showed a denser structure in the centre and a looser one in the border, which was also confirmed by image analysis. This structure heterogeneity in the radial direction and the occurrence of macro-pores close to the radial boundary of the sample can explain the large peaks observed in the radial swelling pressure evolution. Another interesting result is the higher anisotropy found at lower bentonite dry densities, which was also analysed by means ofμCT observation of a sample at low bentonite dry density after the end of test. It was found that the macro-pores, especially those between sand grains, were not filled by swelled bentonite, which preserved the anisotropic microstructure caused by uniaxial compression

关键词： Bentonite/sand mixture Nuclear waste disposal Anisotropy Swelling pressure Microstructure Microfocus X-ray computed tomography(μCT)

Accounting for anisotropic effects in the prediction of the hydro-mechanical response of a ventilated tunnel in an argillaceous rock

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Journal of Rock Mechanics and Geotechnical Engineering 2013年第2期5卷 97-109页

作者： Alain Millard Alex Bond Shigeo Nakama Chengyuan Zhang jean-dominique Barnichon Benoit Garitte Commissariatà l'Energie Atomique et aux Energies Alternatives Gif-sur-Yvette France Quintessa Ltd. Chadwick House Birchwood Park Warrington Cheshire WA3 6AE UK Japan Atomic Energy Agency Tokai Japan Insititute of Rock and Soil Mechanics Chinese Academy of Sciences Institute for Nuclear Radioprotection and Safety Fontenay-aux-roses France Universidad Politécnica de Catalunya Barcelona Spain

In order to investigate the hydro-mechanical （HM） and chemical perturbations induced in an argillaceous formation by forced ventilation during the operational period of a nuclear waste repository, a specific experiment has been performed in a tunnel, at Mont Terri Underground Research Laboratory （URL） in Switzerland. This experiment has been selected in the international project DECOVALEX for model vali- dation and the numerical simulation of this ventilation experiment （VE） is the object of the present paper. Since the argillaceous rock exhibits anisotropic properties, particular attention is given to the evaluation of the effects of various anisotropic features on the predicted results. In situ measurements such as relative humidity （RH）, global water mass extracted, pore water pressure, water content, and relative displace- ments are compared to predictions using both isotropic and anisotropic parameters. Water permeability anisotropy is shown to be the most influencing parameter by far, whereas in situ stress anisotropy has an effect only during the excavation phase. The anisotropy for mechanical parameterization has also some influence, in particular through HM couplings. These HM couplings have the potential to be very significant in terms of providing confidence in describing the experimental observation, and should be considered for further investigation.

关键词： Hydro-mechanical (HM) coupling Numerical modelling Anisotropy Mont Terri Underground Research Laboratory (URL) Ventilation experiment (VE) Argillite

From Farming to Engineering： The Microbiota and Allergic Diseases

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Engineering 2017年第1期3卷 98-109页

作者： dominique Angèle Vuitton jean-Charles Dalphin University Bourgogne Franche-Comte Besancon 25030 France Anergology Network of Franche-Comte Besancon 25030 France

The steady increase of lgE-dependent allergic diseases after the Second World War is a unique phenomenon in the history of humankind. Numerous cross-sectional studies, comprehensive longitudinal cohort studies of children living in various types of environment, and mechanistic experimental studies have pointed to the disappearance of ＂protective factors＂ related to major changes in lifestyle and environment. A common unifying concept is that of the immunoregulatory role of the gut microbiota. This review focuses on the protection against allergic disorders that is provided by the farming environment and by exposure to microbial diversity. It also questions whether and how microbial bioengineering will be able in the future to restore an interplay that was beneficial to the proper immunological development of children in the past and that was irreversibly disrupted by changes in lifestyle. The protective ＂farming environment＂ includes independent and additional influences： contact with animals, stay in barns/stables, and consumption of unprocessed milk and milk products, by mothers during pregnancy and by children in early life. More than the overall quanti- ty of microbes, the biodiversity of the farm microbial environment appears to be crucial for this protection, as does the biodiversity of the gut microbiota that it may provide. Use of conventional probiotics, especially various species or strains of Lactobacillus and Bifidobacterium, has not fulfilled the expectations of allergists and pediatricians to prevent allergy. Among the specific organisms present in cowsheds that could be used for prevention, Acinetobacter （A.） lwoffii F78, Lactococcus （ L.） lactis G121, and Staphylococcus （S.） sciuri W620 seem to be the most promising, based on experimental studies in mouse models of allergic respiratory diseases. However, the development of a new generation of probiotics based on very productive research on the farming environment faces several obstacles that cannot b

关键词： Allergy Farming Microbial biodiversity Immune regulation Microbiota Translational research

Antiplasmodial activity of traditional polyherbal remedy from Odisha, India:Their potential for prophylactic use

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Asian Pacific Journal of Tropical Biomedicine 2015年第12期5卷 982-986页

作者： Prakash Bangalore Nagendrappa jean-Francois Franetich Frederick Gay Audrey Lorthiois Padma Venkatasubramanian dominique Mazier Institute of Trans-Disciplinary Health Sciences and Technology Foundation for Revitalisation of Local Health Traditions Manipal University Cimi-Paris (UPMC UMRS CR7 Inserm U1135 CNRS ERL 8255) AP-HP Pitié-Salpêtrière Hospital Group

Objective:To evaluate the potential prophylactic activity of traditional polyherbal remedy against ***:A traditional polyherbal remedy against malaria from Odisha,India was evaluated for its potential prophylactic activity using in vitro hepatic cell lines assay and the murine malaria system Plasmodium yoelii yoelii/Anopheles ***:The polyherbal extract inhibited the Plasmodium yoelii hepatic stages in vitro(IC500.74 mg/m L),a therapeutic index of *** mice treated with the aqueous extract(2 000 mg/kg/day),peak parasitaemia values were 81%lower in the experimental2.35%±0.14%as compared to controls 12.62%±0.52%(P<0.001),suggesting significant prophylactic ***:The observations provide a proof of concept for a traditional malaria prophylactic remedy used by tribal populations in India.

关键词： Polyherbal remedy Plasmodium Malaria prophylaxis Antiplasmodial activity

Interest of molecular functionalization for electrochemical storage

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Nano Research 2017年第12期10卷 4175-4200页

作者： Bihag Anothumakkool dominique Guyomard Joel Gaubicher Lenaic Madec Institut des Materiaux jean Rouxel (IMN) Universite de Nantes CNRS 2 rue de la Houssiniere BP32229 44322 Nantes Cedex 3 France IPREM-ECP CNRS UMR 5254 Universite de Pau Helioparc Pau Pyrenees 2 av. PierreAngot 64053 Pau Cedex 9 France Reseau sur le Stockage Electrochimique de I'Energie (RS2E) CNRS FR3459 33 Rue Saint Leu 80039 Amiens Cedex France

Despite great interests in electrochemical energy storage systems for numerous applications, considerable challenges remain to be overcome. Among the various approaches to improving the stability, safety, performance, and cost of these systems, molecular functionalization has recently been proved an attractive method that allows the tuning of material surface reactivity while retaining the properties of the bulk material. For this purpose, the reduction of aryldiazonium salt, which is a versatile method, is considered suitable; it forms robust covalent bonds with the material surface, however, with the formation of multilayer structures and sp3 defects （for carbon substrate） that can be detrimental to the electronic conductivity. Alternatively, non-covalent molecular functionalization based on π-π interactions using aromatic ring units has been proposed. In this review, the various advances in molecular functionalization concerning the current limitations in lithium-ion batteries and electrochemical capacitors are discussed. According to the targeted applications and required properties, both covalent and non-covalent functionalizafion methods have proved to be very efficient and versatile. Fundamental aspects to achieve a better understanding of the funcfionalization reactions as well as molecular layer properties and their effects on the electrochemical performance are also discussed. Finally, perspectives are proposed for future implementation of molecular functionalization in the field of electrochemical storage.

关键词： electrochemical storage molecularfunctionalization covalent diazoniumchemistry non-covalent π-π interactions

Diagnosis of Lead Pollution of Surface Waters of a River: Case of the Djiri River in the Republic of Congo

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Journal of Water Resource and Protection 2021年第3期13卷 173-189页

作者： Roch Corneille Ngoubou jean Bienvenu Dinga dominique Nganga Faculty of Sciences and Techniques Doctoral Training in Environmental Geosciences (University Marien NGOUABI) Brazzaville Congo Laboratory of Physico-Chemical Analysis of the Institute for Research in Exact and Natural Sciences Scientific Research Brazzaville Congo

This research work focuses on the physico-chemical analysis of surface water from the Djiri River with the aim of preventing the population against possible water pollution. The analysis of samples taken from the Djiri river revealed the presence of lead in these waters at levels exceeding the WHO guideline values: an average annual pollution (0.93 mg/l) which is visibly higher than the value. WHO guide (0.01 mg/l) in situ data from the Djiri River revealed a significant drop in flow between the 2016 period characterized by a divergence index of 0.82344, thus highlighting a hydrological situation for which national hydrological stakeholders will absolutely have to implement measures, remedial measures or mechanisms to protect this river against possible disappearance by elimination of lead in the water.

关键词： Metallic Pollution Water Quality Standards Indicators and Degree of Pollution