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Are Sc-C and Sc-P Bonds Reactive in Scandium Phosphinoalkylidene Complex？ Insights on a Versatile Reactivity

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Chinese Journal of Chemistry 2018年第10期36卷 904-908页

作者： Weiqing Mao Li Xiang Carlos Alvarez Lamsfus laurent Maron Xuebing Leng Yaofeng Chen State Key Laboratory of Organometallic Chemistry Center for Excellence in Molecular Synthesis Shanghai Institute of Organic Chemistry Univer- sity of Chinese Academy of Sciences Chinese Academy of Sciences 345 Lingling Road Shanghai 200032 China LPCNO CNRS & INSA Universite Paul Sabatier 135 Avenue de Rangueil 31077 Toulouse France

The peculiar electronic structure of scandium phosphinoalkylidene complex [LSc{C（SiMe3）PPh2}THf] （L=[MeC（NDIPP）CHC（NDIPP）Me]-）, DIPP= 2,6-（Pr）2C6H3） leads to an interesting versatile reactivity, which is demonstrated both experimentally and computationally. The complex undergoes [2＋2] cycloaddition reactions with alkynes, and easily activates various X-O bonds such as C-O of propylene oxide, N-O of 3,5-dimethylisoxazole, B-O of pinacolborane and Si-O of triethoxysilane. These reactions occur on the Sc-C bond of the phosphinoalkylidene complex. Interestingly, the Sc-P bond can also be activated as the presence of a Sc-C-P three center π interaction in the complex allows performing C-f activation of 2,6-difluoro- pyridine and 1,2 addition with imine or ketone. The complex also reacts with metal complexes, [（COD）RhCl]2 and （Ph3P）AuCl, to form structural intriguing heterobimetallic complexes.

关键词： alkylidene density functional calculations multiple bonds phosphorus scandium

Risks of temperature extremes over China under 1.5℃ and 2℃ global warming

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Advances in Climate Change Research 2020年第3期11卷 172-184页

作者： SHI Chen JIANG Zhi-Hong ZHU Lian-Hua Xuebin ZHANG YAO Yi-Yi laurent LI Laboratory of Research for Middle-High Latitude Circulation System and East Asian Monsoon Jilin Provincial Key Laboratory of Changbai Mountain Meteorology&Climate ChangeInstitute of Meteorological Sciences of Jilin ProvinceChangchun130062China Key Laboratory of Meteorological Disaster of Ministry of Education Joint International Research Laboratory of Climate and Environment ChangeCollaborative Innovation Center on Forecast and Evaluation of Meteorological DisasterNanjing University of Information Science&TechnologyNanjing210044China School of Mathematics and Statistics Nanjing University of Information Science&TechnologyNanjing210044China Climate Research Division Environment and Climate Change CanadaTorontoOntario M3H 5T4Canada Laboratoire de Météorologie Dynamique CNRSSorbonne UniversitéEcole Normale SupérieureEcole PolytechniqueParis75005France

The Paris Agreement aims to keep global warming to well below 2℃ above pre-industrial levels and to pursue efforts to limit it to 1.5℃,recognizing this will reduce the risks of natural disasters *** changes in the risks of temperature extremes are often associated with changes in the temperature probability distribution,further analysis is still needed to improve understanding of the warm extremes over *** this study,changes in the occurrence probability of temperature extremes and statistic characteristics of the temperature distribution are investigated using the fifth phase of the Coupled Model Intercomparison Project(CMIP5)multimodel simulations from 1861 to *** risks of the once-in-100-year TXx and TNx events are projected to increase by 14.4 and 31.4 times at 1.5℃ ***,the corresponding risks under 2℃ global warming are 23.3 and 50.6,implying that the once-in-100-year TXx and TNx events are expected to occur about every 5 and 2 years over China,*** Tibetan Plateau,Northwest China and south of the Yangtze River are in greater risks suffering hot extremes(both day and night extremes).Changes in the occurrence probability of warm extremes are generally well explained by the combination of the shifts in location and scale parameters in areas with grown variability,i.e.,the Tibetan Plateau for TXx,south of the Yangtze River for both TXx and *** location(scale)parameter leading the risks of once-in-20-year TXx to increase by more than 5(0.25)and 3(0.75)times under 2℃ warming in the Tibetan Plateau and south of the Yangtze River,*** location parameter is more important for regions with decreased variability e.g.,the Tibetan Plateau for TNx,Northwest China for both TXx and TNx,with risks increase by more than 3,6 and 4 times due to changes in location.

关键词： 1.5℃and 2℃global warming Temperature extremes Risk ratios GEV CMIP5

Kinetics of feSe_2 oxidation by ferric iron and its reactivity compared with feS_2

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Science China Chemistry 2014年第9期57卷 1300-1309页

作者： MA Bin NIE Zhe LIU ChunLi KANG MingLiang BARDELLI fabrizio CHEN fanRong CHARLET laurent Beijing National Laboratory for Molecular Sciences Fundamental Science Laboratory on Radiochemistry & Radiation ChemistryCollege of Chemistry and Molecular EngineeringPeking University Sino-french Institute of Nuclear Engineering and Technology Sun Yat-sen University CAS Key Laboratory of Mineralogy and Metallogeny Guangzhou Institute of GeochemistryChinese Academy of Sciences Environmental Geochemistry Group ISTerreUniversity of Grenoble I38041 GrenobleFrance

The mobility and bioavailability of selenium is a major health and environmental issue and a main concern for geological disposal of high-level radioactive waste. Chemically and/or microbially mediated oxidation of insoluble Se-bearing particulate, such as iron selenides, to dissolved and mobile phases controls the transport and distribution of Se in the environment. The oxidation of ferroselite （feSe2） by ferric iron was investigated in anoxic conditions. The redox reaction can be represented by： feSe2 ＋ 2fe3＋ = 2Se^0 ＋ 3fe2＋. Kinetic studies indicated that the reaction can be described by second-order rate law, with rate constants of 0.49±0.01, 0.85±0.02, 1.84±0.04, and 3.29±0.13 L mol^-1 s^-1 at pH 1.62, 1.87, 2.23, and 2.49, respectively. The positive correlation between reaction rate and pH implies that diffusion of fe3＋ oxidant to the mineral surface is the rate-determining step. The strong reactivity of feSe2 towards fe^3＋ suggests that ferric iron may play a significant role in feSe2 oxidation process （e.g., by Se^4＋, 02, etc.） and Se^0 should be the first reaction product. Also, it was shown that the reduction rate of fe^3＋ or Se^4＋ by pyrite （feS2） can be significantly increased in the presence of feSe2, suggesting a stronger reactivity of feSe2 compared with pyrite. The results obtained extend our knowledge about the subtle interaction between Se, pyrite and iron selenides in the environment, and give insight into the transfer of selenium from iron selenides to bio-available selenium （i.e., selenite and selenate） in the Se-rich environment.

关键词： high-level radioactive waste disposal ferroselite oxidative dissolution second-order rate law

Mechanical Properties of Living Adherent Cells :Relationship with Structure and function

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生物医学工程学杂志 2005年第S1期22卷 9-10页

作者： R. fODIL S. féréol E. PLANUS V.M. laurent B. LOUIS D. ISABEY Inserm UMR 651 Fonctions Cellulaire et Moléculaire de l'Appareil Respiratoire et des Vaisseaux Equipe Biomécanique Cellulaire et Respiratoire Faculté de Médecine Créteil 94 010 FranceInserm UMR 651 Fonctions Cellulaire et Moléculaire de l'Appareil Respiratoire et des Vaisseaux Equipe Biomécanique Cellulaire et Respiratoire Faculté de Médecine Créteil 94 010 FranceInserm UMR 651 Fonctions Cellulaire et Moléculaire de l'Appareil Respiratoire et des Vaisseaux Equipe Biomécanique Cellulaire et Respiratoire Faculté de Médecine Créteil 94 010 FranceInserm UMR 651 Fonctions Cellulaire et Moléculaire de l'Appareil Respiratoire et des Vaisseaux Equipe Biomécanique Cellulaire et Respiratoire Faculté de Médecine Créteil 94 010 FranceInserm UMR 651 Fonctions Cellulaire et Moléculaire de l'Appareil Respiratoire et des Vaisseaux Equipe Biomécanique Cellulaire et Respiratoire Faculté de Médecine Créteil 94 010 FranceInserm UMR 651 Fonctions Cellulaire et Moléculaire de l'Appareil Respiratoire et des Vaisseaux Equipe Biomécanique Cellulaire et Respiratoire Faculté de Médecine Créteil 94 010 France

flatness-Based Control in Successive Loops for Unmanned Aerial Vehicles and Micro-Satellites

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Guidance, Navigation and Control 2023年第4期3卷 26-57页

作者： Gerasimos Rigatos Masoud Abbaszadeh Krishna Busawon laurent Dala Unit of Industrial Automation Industrial Systems Institute 26504 Rion Patras Greece Department of ECSE Rensselaer Polytechnic Institute 12065New YorkUSA Nonlinear Control Group University of Northumbria Newcastle NE18STUK Department of Mechanical Engineering University of Northumbria Newcastle NE18ST UK

The control problem for the multivariable and nonlinear dynamics of unmanned aerial vehicles and micro-satellites is solved with the use of a flatness-based control approach which is implemented in successive *** state-space model of(i)unmanned aerial vehicles and(ii)micro-satellites is separated into two subsystems,which are connected between them in cascading *** one of these subsystems can be viewed independently as a differentially flat system and control about it can be performed with inversion of its dynamics as in the case of input–output linearized flat *** state variables of the second subsystem become virtual control inputs for the first *** turn,exogenous control inputs are applied to the first *** whole control method is implemented in two successive loops and its global stability properties are also proven through Lyapunov stability *** validity of the control method is confirmed in two case studies:(a)control and trajectories tracking for the autonomous octocopter,(ii)control of the attitude dynamics of micro-satellites.

关键词： Autonomous octocopter attitude dynamics of micro-satellites multivariable control differential flatness properties flatness-based control in successive loops global stability Lyapunov analysis

Direct palladium/copper oxidative cross-coupling of α-methylstyrene with acrylates

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Science China Chemistry 2010年第9期53卷 1927-1931页

作者： AL-MAKSOUD Walid DJAKOVITCH laurent JAHJAH Mohamad PINEL Catherine Université de Lyon CNRSUMR 5256IRCELYONInstitut de recherches sur la catalyse et l'environnement de Lyon

fully palladium/copper catalytic oxidative cross-coupling of acrylates with α-methylstyrene was performed in a DMSO/AcOH(1:1) mixture at 60℃ in the *** improves previous procedures which employed stoichiometric amounts of copper and *** various acrylates were effectively coupled to α-methylstyrene giving the expected compounds in moderate to good yields(44%-65%) as a mixture of E and Z isomers.

关键词： direct cross-coupling oxidative couplings palladium copper catalytic procedures olefin cross-coupling

Development of a short duration method to assess the envelope thermal performance of multi-family housings

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Building Simulation 2023年第4期16卷 527-545页

作者： Lorena de Carvalho Araujo Simon Thébault laurent Mora Thomas Recht Alain Sempey Patrick Schalbart Michae Cohen CSTB 84 Av.Jean JauresChamps-sur-Marne77420France Bordeaux University 351 Cours de la LiberationTalence33405France MINES ParisTech Centre for Energy Efficiency of Systems5 rue Léon BlumPalaiseau91120France

Building energy efficiency is a key factor in reducing CO_(2) *** this reason,European Union(EU)member states have developed thermal regulations to ensure building thermal *** results are often based on results achieved with building simulation software during the design ***,the actual thermal performance can deviate significantly from the predicted one,and this difference is known as the energy performance *** indicators of the actual thermal performance are a valuable tool to guarantee building *** indicators,including the heat transfer coefficient(HTC)and the heat loss coefficient(HLC),can be estimated by the application of in situ *** multi-family housing and tertiary sector buildings are an important part of the building stock,mature methods to measure their thermal performance are *** paper presents a short-duration method for assessing the HTC in large building typologies using a sampling *** method was applied in a four-storey building model under different conditions to study the limits of the method and to improve indicator bias and *** quality was strongly influenced by the external weather conditions,the temperature variation during the protocol and the heat exchange with the adjacent *** winter conditions and with stable indoor temperatures,the method had a high accuracy when the protocol was applied for half a *** is recommended that the protocol be used over two days to improve indicator quality under less favorable test conditions.

关键词： building envelope thermal performance HTC estimation multi-family housing

A diagnostic protocol designed for determining allergic causes in patients with blood eosinophilia

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Military Medical Research 2017年第4期4卷 181-192页

作者： Jean-françois Magnaval Guy laurent Noemie Gaudré Judith fillaux Antoine Berry Department of Medical Parasitology Faculty of MedicineToulouse University37 aliees Jules-GuesdeToulouseFrance Purpan Center for Pathophysiology INSERM UMR Ulo43CNRS UMR S282Toulouse UniversityToulouseFrance Department of Hematology Toulouse University HospitalsToulouseFrance Cancer Institute Toulouse University and OncopoleToulouseFrance Department of Parasitology and Mycology Toulouse University HospitalsToulouseFrance PharmaDev IRD UMR 152Toulouse UniversityToulouseFrance

Background: Blood eosinophilia is a common laboratory abnormality, and its characterization frequently represents a quandary for primary care physicians. Consequently, in france, specialists and particularly hematologists, often must investigate patients who present with blood eosinophilia that often, but not always, occurs because of allergic causes. Both the Departments of Hematology and Parasitology at Toulouse University Hospitals established a collaboration to rule out allergic causes of eosinophilia, particularly helminthiases, prior to initiating more sophisticated ***: Since 2004, the authors employed the same protocol to investigate eosinophilic outpatients who attended the clinic of Parasitology at Toulouse University Hospitals, and they reported the performance of this diagnostic procedure that was designed to be rapid(no hospitalization required) and only moderately ***: A total of 406 patients who presented with blood eosinophilia greater than 0.5(×10~9, giga cells per litter, G/L) had an allergic etiology in 350(86.2%) cases. Among the remaining 56 subjects, 17 did not undergo a follow-up and 39 were referred to another specialized department, mostly Hematology. However, only 21 patients attended then were subsequently investigated. Non-allergic causes of eosinophilia, including 3 cases of the lymphoid variant of hypereosinophilic syndrome and 2 cases of myeloproliferative disorder, were identified in 14 patients, whereas 7 remained diagnosed as having idiopathic ***: This study underlines the need to investigate patients presenting with even moderate blood eosinophilia. The work-up that was employed appears to be efficient and versatile and may be used by any medical specialist, such as in hematology, infectious disease, or internal medicine departments, who needs to investigate eosinophilic patients and should initially rule out any etiology of allergic eosinophilia.

关键词： Blood eosinophilia Diagnostic protocol Classification Secondary eosinophilias Allergy Helminthiases

Comparison of Data Screening Methods for Evaluating School-Level fitness Patterns in Youth: findings from the NfL PLAY 60 fITNESSGRAM Partnership Project

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Open Journal of Preventive Medicine 2014年第11期4卷 876-886页

作者： Pedro f. saint-Maurice Gregory J. Welk Yang Bai Kelly Allums-featherston Department of Kinesiology Iowa State University Ames USA School of Psychology-CIPsi University of Minho Braga Portugal NfL PLAY 60 fITNESSGRAM® Project The Cooper Institute&reg Dallas USA

Background: There has been a great interest in tracking health-related fitness across the United States. The NfL PLAY 60 fITNESSGRAM Partnership Project (NfL P60fGPP) is a large participatory research network that involves the surveillance of fitness among more than 1000 schools spread throughout the country. fitness data are collected by school staff and therefore these data can vary in quality and representativeness. Therefore, careful screening procedures are needed to ensure that the data can reflect actual patterns in the schools. This study examined the impact of different data screening procedures on outcomes of aerobic fitness (Af) collected from the NfL P60fGPP. Methods: Data were compiled from 149,101 youth from 504 schools and were processed using the established age- and gender-specific Af fITNESSGRAM health-related standards. Data were subjected to three different screening procedures (based on grade size and boy-to-girl ratio per grade). Linear models were computed to obtain unadjusted and adjusted (for age, BMI-Z, and socio-economic status) estimates of % youth in the Healthy fitness Zone (HfZ) in order to determine if, 1) there were differences in % in the HfZ and 2) if differences could be explained by changes in the representativeness of the sample due to the different data screening procedures. Results: Depending on the screening procedure used, the final sample ranged from 96,999 (no screening) to 46,572 youth (most stringent criteria). The proportion of youth achieving appropriate levels of Af ranged from 56% to 61% with unscreened data resulting in consistently lower percentages of youth achieving the standard (P fferences were not explained by possible changes in demographic characteristics as the result of applying different screening criteria. Conclusions: The findings demonstrate the importance of establishing appropriate screening procedures that maximize sample size while also ensuring generalizability of the fin

关键词： Aerobic fitness Assessment Data Reduction Public Health Surveillance