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Macroscopic,thermodynamic,kinetic and microscopic study of nitric acid pickling of Elektron 21(EV31A)magnesium alloy

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Journal of Magnesium and Alloys 2014年第4期2卷 363-376页

作者： Benjamin Mouls Laurent Arurault pierre-louis taberna Corine Bonningue Universitéde Toulouse CIRIMATUPS/INPT/CNRS118 route de Narbonne 31062Toulouse Cedex 9France

The study of pickling of the EL21T6 substrate in a nitric acid bath firstly provided knowledge of the influence of the different experimental parameters(concentration of acid,temperature and stirring of the solution)in relation to the etching *** experimental part led to the choice of standard pickling(T_(bath)=25℃,moderate stirring(250 rpm),[HNO_(3)]=1.20 mol/L,duration of 2 min)so as to obtain constant removal of material,even after several uses of the pickling *** observations also confirmed that in these operating conditions,pickling concerns both the grains of the matrix and the precipitates of type Mg3(Nd,Gd),leading to uniform removal of material from the *** from a number of assumptions,thermodynamic and chemical kinetic studies then allowed a pickling mechanism to be proposed and led to obtaining values for the corresponding kinetic parameters(order of reaction,constant of mean rate,activation energy)to be obtained.

关键词： Magnesium alloy Elektron 21 Pickling Nitric acid Chemical kinetic Thermodynamic

Molten Salt-Shielded Synthesis(MS^(3))of MXenes in Air

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Energy & Environmental Materials 2023年第2期6卷 159-164页

作者： Jinjin Chen Qianqian Jin Youbing Li Hui Shao Pengcheng Liu Ying Liu pierre-louis taberna Qing Huang Zifeng Lin Patrice Simon College of Materials Science and Engineering Sichuan UniversityChengdu 610065China Materials Science and Engineering Research Center Guangxi University of Science and TechnologyLiuzhou 545006China Engineering Laboratory of Advanced Energy Materials Ningbo Institute of Materials Technology and EngineeringChinese Academy of SciencesNingbo 315201China Qianwan Institute of CNiTECH Zhongchuangyi RoadHangzhou Bay DistrictNingbo 315336China CIRIMAT Universit´e de ToulouseCNRSToulouse 31400France R´eseau sur le Stockage Electrochimique de l’Energie(RS2E)FR CNRS no 3459 Engineering Research Center of Alternative Energy Materials&Devices Ministry of EducationChina

MXenes are two-dimensional transition metal carbides and/or nitrides with unique physiochemical properties and have attracted extensive interest in numerous ***,current MXene synthesis methods are limited by hazardous synthesis conditions,high production costs,or difficulty in largescale ***,a general,safe,cost-effective,and scalable synthesis method for MXenes is ***,we report the fast synthesis of MXenes in the open air using a molten salt-shielded synthesis(MS^(3))method,which uses Lewis-acid salts as etchants and a low-melting-point eutectic salt mixture as the reaction medium and shield to prevent MXene oxidation at high *** and nitride MXenes,including Ti_(3)C_(2)T_(x),Ti_(2)CT_(x),Ti_(3)CNT_(x),and Ti_(4)N_(3)T_(x),were successfully synthesized using the MS^(3) *** also present the flexibility of the MS^(3) method by scaling the etching process to large batches of 20 and 60 g of Ti_(3)AlC_(2) MAX precursor in one *** used as negative electrodes,the prepared MS^(3)-MXenes delivered excellent electrochemical properties for high-rate Li-ion storage.

关键词： carbides lithium-ion storage molten salt synthesis MXene nitrides

Cavity optomechanics with directionally squeezed light

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Science China(Physics,Mechanics & Astronomy) 2024年第6期67卷 181-182页

作者： pierre Meystre Department of Physics and College of Optical Sciences University of ArizonaTucson 85721USA

It is well understood that the Heisenberg uncertainty principle imposes a fundamental limit on the precision of quantum *** way to get around this difficulty is to exploit quantum states that minimize the uncertainty on the observable of interest,increasing in the process the uncertainty on the conjugate *** states of the electromagnetic field.

关键词： field observable quantum

Decomposition mechanisms of nuclear-grade cationic exchange resin by advanced oxidation processes:Statistical molecular fragmentation model and DFT calculations

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Journal of Environmental Sciences 2024年第1期135卷 433-448页

作者： Xiang Meng pierre Désesquelles Lejin Xu Department of Nuclear Engineering and Technology School of Energy and Power EngineeringHuazhong University of Science&TechnologyWuhan 430074China CNRS Laboratoire de Physique des Gaz et des PlasmasUniversitéParis-SaclayOrsay 91405France State Key Laboratory of Coal Combustion School of Energy and Power EngineeringHuazhong University of Science and TechnologyWuhan 430074China

The treatment and disposal of radioactive waste are presently facing great *** ion exchange resins have become a focus of attention due to their high production and serious environmental *** this paper,a simplified model of cationic exchange resin is proposed,and the degradation processes of cationic resin monomer initiated by hydroxyl radicals(·OH)are clarified by combining statistical molecular fragmentation(SMF)model and density functional theory(DFT)*** prediction of active sites indicates that the S-O bonds and the C-S bond of the sulfonic group are more likely to react during the *** meta-position of the sulfonic group on the benzene ring is the most active site,and the benzene ring without the sulfonic group has a certain *** C11-C14 and C17-C20 bonds,on the carbon skeleton,are the most easily *** is also found that dihydroxy addition and elimination reactions play a major role in the process of desulfonation,carbon skeleton cleavage and benzene ring *** decomposition mechanisms found through the combination of physical models and chemical calculations,provide theoretical guidance for the treatment of complex polycyclic aromatic hydrocarbons.

关键词： Cationic exchange resin Statistical molecular fragmentation model Density functional theory Hydroxyl radical Decomposition mechanism

A spotlight on dosage and subject selection for effective neuroprotection: exploring the central role of mitochondria

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Neural Regeneration Research 2025年第4期20卷 1081-1082页

作者： John Mitrofanis Jonathan Stone Michael R.Hamblin pierre Magistretti Alim-louis Benabid Glen Jeffery Fonds Clinatec UniversitéGrenoble AlpesGrenobleFrance School of Medical Science University of SydneySydneyAustralia Faculty of Health Sciences University of JohannesburgJohannesburgSouth Africa King Abdullah University of Science and Technology ThuwalSaudi Arabia Institute of Ophthalmology University College LondonLondonUK

Neurons are notoriously vulnerable cell *** the slightest change in their internal and/or external environments will cause much distress and dysfunction,leading often to their death.A range of pathological conditions,including stroke,head trauma,and neurodegenerative disease,can generate stress in neurons,affecting their survival and proper *** most neural pathologies,mitochondria become dysfunctional and this plays a pivotal role in the process of cell *** challenge over the last few decades has been to develop effective interventions that improve neuronal homeostasis under pathological *** interventions,often referred to as disease-modifying or neuroprotective,have,however,proved frustratingly elusive,at both preclinical and,in particular,clinical *** this perspective,we highlight two factors that we feel are key to the development of effective neuroprotective *** are:firstly,the choice of dose of intervention and method of application,and secondly,the selection of subjects,whether they be patients or the animal model.

关键词： protective dosage distress

Developing biophilic intermediate spaces for Arctic housing:Optimizing the thermal,visual,and energy performance

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Building Simulation 2024年第6期17卷 857-875页

作者： Tarlan Abazari AndréPotvin louis Gosselin Claude MH Demers GRAP(Groupe de recherche en ambiance physiques) School of ArchitectureLaval UniversityQuébecCanada Department of Mechanical Engineering Faculty of Science and EngineeringLaval UniversityQuébecCanada

Connecting occupants to the outdoor environment and incorporating biophilic design principles are challenging in extreme Arctic climatic *** Arctic housing models do not provide efficient thermal and daylight transitions which are essential for the well-being and cultural needs of their *** address these challenges,this research develops free-running biophilic intermediate spaces,integrated into an existing Arctic housing *** simulation methods are employed to optimize the primary and secondary architectural design variables for 26 case studies of intermediate *** variables include volume,transparency ratio,and *** variables include materials and physical ***,Daylight Factor/Autonomy,and Energy Use are evaluated as performance *** reveal that free-running intermediate spaces with 6 meters depth and a transparency ratio above 50%provide efficient indoor–outdoor transitions regarding thermal,visual,and energy *** architectural configurations contribute to an approximately 5%reduction in energy consumption within the housing unit compared to the *** side windows prevents the risk of overheating during the summer by reducing the average indoor temperature of intermediate spaces by 7°C but increases the overall energy *** a potential alternative to double-glazing,polycarbonate sheets enable efficient thermal performance by increasing the average indoor temperature of intermediate spaces by approximately 15°C during the cold Arctic *** polycarbonate sheets results in a 16.6%reduction in energy consumption compared to using double-glazing material in intermediate space,and a 26%reduction from the *** outcomes contribute to efficient indoor–outdoor connections and energy efficiency in Arctic housing.

关键词： Arctic housing intermediate spaces biophilic design positive thermal transitions daylight availability energy efficiency

Scanning transmission electron microscopy and atom probe tomography analysis of non-stoichiometry long-period-stacking-ordered structures in Mg-Ni-Y/Sm alloys

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Journal of Magnesium and Alloys 2024年第3期12卷 954-965页

作者： Yimeng Chen Manuel Legrée Jean-louis Bobet Alexander Kvit CAMECA Instruments Inc MadisonWI 53711USA ICMCB Universitéde BordeauxPessacCEDEX 33608France NIAC&Materials Science Department University of WisconsinMadisonWI 53706USA

The long-period-stacking-ordered(LPSO)structure affects the mechanical,corrosion and hydrolysis properties of Mg *** current work employs high angle annular dark field-scanning transmission electron microscopy(HAADF-STEM)and atom probe tomography(APT)to investigate the structural and local chemical information of LPSO phases formed in Mg-Ni-Y/Sm ternary alloys after extended isothermal *** on the alloying elements and their concentrations,Mg-Ni-Y/Sm develops a two-phase LPSO+α-Mg structure in which the LPSO phase contains defects,hybrid LPSO structure,and Mg ***-STEM and APT indicate non-stoichiometric LPSO with incomplete Ni_(6)(Y/Sm)_(8) *** addition,the APT quantitatively determines the local composition of LPSO and confirms the presence of Ni within the Mg bonding *** results provide insight into a better understanding of the structure and hydrolysis properties of LPSO-Mg alloys.

关键词： Magnesium alloys Long-range ordering Atom probe tomography(APT) STEM HAADF Hydrolysis properties.

Re-evaluation of recent research on metabolic utilization of energy in poultry: Recommendations for a net energy system for broilers

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Animal Nutrition 2024年第1期16卷 62-72页

作者： Jean Noblet Aye-Cho Tay-Zar Shu-Biao Wu Pairat Srichana pierre Cozannet pierre-Andre Geraert Mingan Choct INRAE Charoen Pokphand Foods Public Company Limited (CPF) School of Environmental and Rural Science University of New England Adisseo France S.A.S.

Different energy systems have been proposed for energy evaluation of feeds for domestic animals. The oldest and most commonly used systems take into account the fecal energy loss to obtain digestible energy(DE), and fecal, urinary and fermentation gases energy losses to calculate metabolizable energy(ME). In the case of ruminants and pigs, the net energy(NE) system, which takes into account the heat increment associated with the metabolic utilization of ME, has progressively replaced the DE and ME systems over the last 50 years. For poultry, apparent ME(AME) is used exclusively and NE is not yet used widely. The present paper considers some important methodological points for measuring NE in poultry feeds and summarizes the available knowledge on NE systems for poultry. NE prediction equations based on a common analysis of three recent studies representing a total of 50 complete and balanced diets fed to broilers are proposed; these equations including the AME content and easily available chemical indicators have been validated on another set of 30 diets. The equations are applicable to both ingredients and complete diets. They rely primarily on an accurate and reliable AME value which then represents the first limiting predictor of NE value. Our analysis indicates that NE would be a better predictor of broiler performance than AME and that the hierarchy between feeds is dependent on the energy system with a higher energy value for fat and a lower energy value for protein in an NE system. Practical considerations for implementing such an NE system from the commonly used AME or AMEn(AME adjusted for zero nitrogen balance) systems are presented. In conclusion, there is sufficient information to allow the implementation of the NE concept in order to improve the accuracy of feed formulation in poultry.

关键词： Poultry Feed evaluation Net energy Energy system

The importance of increasing primary vaccinations against COVID-19 in Europe

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Infectious Disease Modelling 2024年第1期9卷 1-9页

作者： pierre-Yves Boelle Eugenio Valdano Sorbonne Universite INSERMInstitut Pierre Louis d’Epidemiologie et de Sante PubliqueF75012ParisFrance

In the European Union,mass vaccination against COVID-19 staved off the strict restrictions that had characterized early epidemic ***,vaccination campaigns are focusing on booster doses,and primary vaccinations have all but ***,52 million European adults are *** investigated if reaching the still unvaccinated population in future vaccination campaigns would substantially decrease the current burden of COVID-19,which is *** focused on vaccination homophily,whereby those who are unvaccinated are mostly in contact with other unvaccinated,making COVID-19 circulation *** quantified vaccination homophily and estimated its impact on COVID-19 *** used an online survey of 1,055,286 people from 22 European countries during early *** computed vaccination homophily as the association between reported vaccination status and perceived vaccination uptake among one's own social contacts,using a case-referent design and a hierarchical logistic *** used this information in an analysis of the COVID-19 reproduction ratio to determine the impact of vaccine homophily in *** homophily was present and strong everywhere:the average odds ratio of being vaccinated for a 10-percentage-point increase in coverage among contacts was 1.66(95%CI=(1.60,1.72)).Homophily was positively associated with the strictness of COVID-19-related restrictions in 2020(Pearson=0.49,P=.03).In the countries studied,12%-to-18%of the reproduction ratio would be attributable to vaccine *** vaccination homophily may curb the reproduction ratio substantially even to the point of preventing recurrent epidemic *** addition to boosting those already vaccinated,increasing primary vaccination should remain a high priority in future vaccination campaigns,to reduce vaccination homophily:this combined strategy may decrease COVID-19 burden.

关键词： COVID-19 Vaccination campaign Reproduction ratio Vaccination homophily Survey Europe