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Effect of Cu promoter on ni-based SBA-15 catalysts for partial oxidation of methane to syngas

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Journal of natural Gas Chemistry 2009年第4期18卷 392-398页

作者： fabien Habimana Xiujin Li Shengfu Ji Bao Lang Daoan Sun Chengyue Li State Key Laboratory of Chemical Resource Engineering Beijing University of Chemical Technology Beijing 100029 China Department of Environmental Engineering Beijing University of Chemical Technology Beijing 100029 China

A series of ni/SBA-15 catalysts with 5wt% to 15wt% ni content as well as a series of 12.5%ni/Cu/SBA-15 catalysts with 1% to 10% copper content were prepared by the impregnation method. The catalytic performance for partial oxidation of methane was investigated in a continuous flow microreactor under atmospheric pressure. The textural and chemical properties of the catalysts were characterized by XRD, TEM, BET and Hz-TPR techniques. The results indicated that the catalysts modified with Cu promoter showed better performance than those without modification. For the 12.5%ni/2.5%/Cu/SBA-15 catalyst, at 850 ℃ the conversion of CH4 reached 97.9% and the selectivity of CO and H2 reached 98.0% and 96.0%, respectively. In XRD patterns of the ni/Cu/SBA-15 catalyst with 7.5 to 10% Cu contents there were CuO characteristic peaks beside niO characteristic peaks. The mesoporous structure of SBA-15 was retained in all of the catalysts. TPR analysis of the catalysts revealed that a strong interaction between ni, Cu promoter and SBA-15 support may be existed. This interaction enhanced significantly the redox properties of the catalysts resulting in the higher catalytic activity.

关键词： Cu promoter ni-based catalyst SBA-15 methane partial oxidation of methane

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Metabolic reprogramming in inflammaging and aging in T cells

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Life Metabolism 2023年第5期2卷 17-24页

作者： Alessio Bevilacqua Ping-Chih Ho fabien Franco Department of Fundamental Oncology University of Lausanne1007 LausanneSwitzerland Ludwig Institute for Cancer Research University of Lausanne1066 EpalingesSwitzerland

Aging represents an emerging challenge for public health due to the declined immune responses against pathogens, weakened vaccination efficacy, and disturbed tissue homeostasis. Metabolic alterations in cellular and systemic levels are also known to be cardinal features of aging. Moreover, cellular metabolism has emerged to provide regulations to guide immune cell behavior via modulations on signaling cascades and epigenetic landscape, and the aberrant aging process in immune cells can lead to inflammaging, a chronic and low-grade inflammation that facilitates aging by perturbing homeostasis in tissues and organs. Here, we review how the metabolic program in T cells is influenced by the aging process and how aged T cells modulate inflammaging. In addition, we discuss the potential approaches to reverse or ameliorate aging by rewiring the metabolic programming of immune cells.

关键词： immunometabolism inflammaging T cells

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Publisher Correction: Finding the semantic similarity in single-particle diffraction images using self-supervised contrastive projection learning

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npj Computational Materials 2023年第1期9卷 1732-1733页

作者： Julian Zimmermann fabien Beguet Daniel Guthruf Bruno Langbehn Daniela Rupp ETH Zürich Zürich Switzerland (GRID:grid.5801.c) (ISNI:0000 0001 2156 2780) Technische Universität Berlin Berlin Germany (GRID:grid.6734.6) (ISNI:0000 0001 2292 8254) ETH Zürich Zürich Switzerland (GRID:grid.5801.c) (ISNI:0000 0001 2156 2780) Max-Born-Institut Berlin Germany (GRID:grid.419569.6) (ISNI:0000 0000 8510 3594)

Correction to:npj Computational Materials https://***/10.1038/s41524-023-00966-0,published online 16 February 2023 The original version of this Article contained several typographical errors in both the PDF and the HTML *** the first paragraph of‘Introduction’,the sentence‘(The phrase was coined by nobel laureate Francis Crick in his book What Mad Pursuit:A personal view of scientific discovery)’duplicated reference *** sentence and brackets have been removed in the corrected version.

关键词： semantic similarity projection

Extraordinary piezoelectric effect induced in two-dimensional rare earth monochalcogenides via reducing system dimensionality

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Journal of Materiomics 2023年第1期9卷 72-81页

作者： neveen I.Atallah Maged El-Kemary fabien Pascale Khaled E.El-Kelany Institute of nanoscience and nanotechnology Kafrelsheikh University33516Kafr el-skiekhEgypt Universite de Lorraine-nancy CNRSLaboratoire de Physique et Chimie TheoriquesUMR 7019Vandoeuvre-les-NancyFrance

Piezoelectricity is pivotal for applications in micro/nanoelectromechanical systems(MEMS/nEMS).Inducing such a property in 2D systems via the reduction of the dimensionality of their corresponding 3D bulk is here *** on DFT theory and Gaussian-type-localized basis sets,the structural,electronic,mechanical,and piezoelectric properties of both 3D and 2D rare earth monochalcogenides RmX(Rm=Tm,Yb,Lu,and X=S,Se,Te)are investigated using the CRYSTAL *** intriguingly,the 2D LuX compounds display a buckled structure,where the Lu and X atoms protrude from the monolayer surface leading to an additional out-of-plane piezoelectric effect;(e_(31)=2104.84,1770.28,1689.79 pC/m,and d31=56.37,49.76,and 147.90 pm/V for LuS,LuSe,and LuTe,respectively).Such piezoelectric response is two orders of magnitude larger than the one of recently reported 2D ferroelectric MXenes,and is nearly thirty times larger than the commonly used Aln and Gan bulk ***,the reduced elastic constants obtained,when compared to other 2D materials,confirm the flexibility and softness of the considered 2D systems.

关键词： 2D materials Rare earth monochalcogenides DFT Gaussian basis CRYSTAL code Piezoelectric effect MEMS/nEMS

Anomaly Detection in Textured Images with a Convolutional neural network for Quality Control of Micrometric Woven Meshes

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Fluid Dynamics & Materials Processing 2022年第6期18卷 1639-1648页

作者： Pierre-Frédéric Villard Maureen Boudart Ioana Ilea fabien Pierre Universitéde Lorraine CnRS Inria LORIA Nancy54000France IUT de Saint-DiéUniversitéde Lorraine Saint-Dié-des-Vosges88100France Technical University of Cluj-napoca Cluj-Napoca400114Romania

Industrial woven meshes are composed of metal materials and are often used in construction,industrial and residential activities or *** objective of this work is defect detection in industrial fabrics in the quality control *** order to overcome the limitations of manual methods,which are often tedious and time-consuming,we propose a strategy that can automatically detect defects in micrometric steel meshes by means of a Convolutional neural *** database used for such a purpose comes from real problem data for anomaly detection in micrometric woven *** detection is performed through supervised classification with a Convolutional neural network using a VGG19 *** define a pipeline and a strategy to tackle the related small amount of *** includes i)augmenting the database with translation,rotation and symmetry,ii)using pre-trained weights and iii)checking the learning curve behaviour through *** obtained results show that,despite the small size of our databases,detection accuracy of 96%was reached.

关键词： Industrial fabrics defects detection deep learning convolutional neural network VGG19

Embedding MSCs in Si-HPMC hydrogel decreased MSC-directed host immune response and increased the regenerative potential of macrophages

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Regenerative Biomaterials 2022年第1期9卷 490-500页

作者： Christelle Demarquay Lara Moussa Gildas Réethorée fabien Milliat Pierre Weiss noëlle Mathieu Human Health Department IRSNFrench Institute for Radiological Protection and Nuclear SafetySERAMEDLRMedFontenay-aux-Roses 92262France Facultéde Chirurgie Dentaire Regenerative Medicine and Skeleton(RMeS)LaboratoryUniversite de NantesNantes 44042France

Embedding mesenchymal stromal cells(MSCs)in biomaterial is a subject of increasing interest in the field of Regenerative *** up the clinical use of MSCs is dependent on the use of non-syngeneic models in accordance with Good Manufacturing Practices(GMP)requirements and on *** this end,in this study,we analyzed the in vivo host immune response following local injection of silanized hydroxypropyl methylcellulose(Si-HPMC)-embedded human MSCs in a rat model developing colorectal damage induced by ionizing *** and lymphocytes from mesenteric lymph nodes were harvested in addition to colonic *** set up tests,using flow cytometry and a live imaging system,to highlight the response to specific antibodies and measure the cytotoxicity of lymphocytes against injected *** demonstrated that Si-HPMC protects MSCs from specific antibodies production and from apoptosis by *** also observed that Si-HPMC does not modify innate immune response infiltrate in vivo,and that in vitro co-culture of Si-HPMC-embedded MSCs impacts macrophage inflammatory response depending on the microenvironment but,more importantly,increases the macrophage regenerative response through Wnt-family and VEGF gene *** study furthers our understanding of the mechanisms involved,with a view to improving the therapeutic benefits of biomaterial-assisted cell therapy by modulating the host immune *** decrease in specific immune response against injected MSCs protected by Si-HPMC also opens up new possibilities for allogeneic clinical use.

关键词： Si-HPMC hydrogel mesenchymal stromal cells host immune response regenerative medicine

An atypical nLR gene confers bacterial wilt susceptibility in Arabidopsis

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Plant Communications 2023年第5期4卷 277-294页

作者： Choghag Demirjian narjes Razavi Gang Yu Baptiste Mayjonade Lu Zhang fabien Lonjon fabien Chardon Se bastien Carrere Je rome Gouzy Ste phane Genin Alberto PMacho Fabrice Roux Richard Berthome fabienne Vailleau LIPME Universite de ToulouseINRAECNRSCastanet-TolosanFrance Shanghai Center for Plant Stress Biology CAS Center for Excellence in Molecular Plant SciencesChinese Academy of SciencesShanghaiChina Universite Paris-Saclay INRAEAgroParisTechInstitut Jean-Pierre Bourgin(IJPB)78000 VersaillesFrance Present address:Department of Cell&Systems Biology University of TorontoTorontoONCanada Present address:Department of Biology NYU12 Waverly PlaceNew YorkNY 10003USA

Quantitative disease resistance(QDR)remains the most prevalent form of plant resistance in crop fields and wild ***-wide association studies(GWAS)have proved to be successful in deciphering the quantitative genetic basis of complex traits such as *** unravel the genetics of QDR to the devastating worldwide bacterial pathogen Ralstonia solanacearum,we performed a GWAS by challenging a highly polymorphic local mapping population of Arabidopsis thaliana with four *** type III effector(T3E)mutants,identified as key pathogenicity determinants after a first screen on an *** core collection of 25 *** most quantitative trait loci(QTLs)were highly specific to the identity of the T3E mutant(ripAC,ripAG,ripAQ,and ripU),we finely mapped a common QTL located on a cluster of nucleotide-binding domain and leucine-rich repeat(nLR)genes that exhibited structural *** functionally validated one of these nLRs as a susceptibility factor in response to ***,named it Bacterial Wilt Susceptibility 1(BWS1),and cloned two alleles that conferred contrasting levels of *** characterization indicated that expression of BWS1 leads to suppression of immunity triggered by different *** *** addition,we showed a direct interaction between BWS1 and RipAC T3E,and BWS1 and SUPPRESSOR OF G2 ALLELE OF skp1(SGT1b),the latter interaction being suppressed by ***,our results highlight a putative role for BWS1 as a quantitative susceptibility factor directly targeted by the T3E RipAC,mediating negative regulation of the SGT1-dependent immune response.

关键词： Ralstonia solanacearum typeⅢeffectors Arabidopsis thaliana GWAS R gene susceptibility

Reflecting petawatt lasers off relativistic plasma mirrors:a realistic path to the Schwinger limit

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High Power Laser Science and Engineering 2021年第1期9卷 56-68页

作者： fabien Quéré Henri Vincenti LIDYL CEA-CNRSUniversitéParis-Saclay91191 Gif-sur-YvetteFrance

The quantum vacuum plays a central role in physics. Quantum electrodynamics(QED) predicts that the properties of the fermionic quantum vacuum can be probed by extremely large electromagnetic fields. The typical field amplitudes required correspond to the onset of the ‘optical breakdown’ of this vacuum, expected at light intensities>4.7×10^(29) W/cm^(2). Approaching this ‘Schwinger limit’ would enable testing of major but still unverified predictions of power lasers. To close this considerable gap, a promising paradigm consists of reflecting these laser beams off a mirror in relativistic motion, to induce a Doppler effect that compresses the light pulse in time down to the attosecond range and converts it to shorter wavelengths, which can then be focused much more tightly than the initial laser light. However, this faces a major experimental hurdle: how to generate such relativistic mirrors? In this article, we explain how this challenge could nowadays be tackled by using so-called ‘relativistic plasma mirrors’. We argue that approaching the Schwinger limit in the coming years by applying this scheme to the latest generation of petawatt-class lasers is a challenging but realistic objective.

关键词： ultraintense laser-matter interaction strong-field quantum electrodynamics plasma mirrors attosecond light pulses

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Knotting ligands to control metal coordination geometry

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Science China Chemistry 2024年

作者： fabien B.L.Cougnon Department of Chemistry and nanoscience Centre University of Jyv?skyl?

Zinc is a metal of particular importance for life [1]. It is the most abundant transition metal in biological systems after iron and contributes both structural and catalytic roles to many cellular processes. The properties of ZnII, unlike those of any other first-row transition metal ions, explain its biological relevance. Due to its filled d-shell orbitals, ZnIIis redox-stable, has a ligand-field energy stabilization of zero and, consequently, no typical coordination number and geometry. Zinc metalloproteins exploit these features to carry a broad range of chemical reactions in mild *** metalloenzymes, unsaturated ZnIIcentres often act as redox-stable Lewis acids. The protein backbone provides a highly preorganized environment around the metal centre and accompanies the changes in coordination geometry occurring as substrate transformation proceeds, thereby modulating the metal reactivity.

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