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Wettability,reactivity,and interface structure in Mg/Ni system

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journal of Magnesium and Alloys 2024年第2期12卷 659-672页

作者： S.Terlicka N.Sobczak Ł.Maj p.Darłak j.j.Sobczak Institute of Metallurgy and Materials Science Polish Academy of Sciences25 Reymonta Str.KrakowPoland Faculty of Foundry Engineering AGH University23 Reymonta Str.KrakowPoland

The sessile drop method was applied to the experimental investigation of the wetting and spreading behaviors of liquid Mg drops on pure Ni substrates.For comparison,the experiments were performed in two variants:(1)using the Capillary purification(Cp)procedure,which allows the non-contact heating and squeezing of a pure oxide-free Mg drop;(2)by classical Contact Heating(CH)procedure.The high-temperature tests were performed under isothermal conditions(Cp:760℃for 30 s;CH:715℃for 300 s)using Ar+5 wt%H_(2) atmosphere.During the sessile drop tests,images of the Mg/Ni couples were recorded by CCD cameras(57 fps),which were then applied to calculate the contact angles of metal/substrate couples.Scanning and transmission electron microscopy analyses,both coupled with energy-dispersive X-ray spectroscopy,were used for detailed structural characterization of the solidified couples.It was found that an oxide-free Mg drop obtained by the Cp procedure showed a wetting phenomenon on the Ni substrate(an average contact angleθpreading and good wetting over the Ni substrate(θ_((Cp))~20°in 5 s)to form a final contact angle ofθ_(f(Cp))~18°.In contrast,a different wetting behavior was observed for the CH procedure,where the unavoidable primary oxide film on the Mg surface blocked the spreading of liquid Mg showing apparently non-wetting behavior after 300 s contact at the test temperature.However,in both cases,the deep craters formed in the Ni substrates under the Mg drops and significant change in the structure of initially pure Mg drops to Mg-Ni alloys suggest a strong dissolution of Ni in liquid Mg and apparent values of the final contact angles measured for the Mg/Ni system.

关键词： Magnesium-based alloys Sessile drop tests Capillary purification procedure Wettability Reactivity Contact angle

Drought events influence nutrient canopy exchanges and green leaf partitioning during senescence in a deciduous forest

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Forest Ecosystems 2024年第1期11卷 110-119页

作者： j.Touche C.Calvaruso p.De Donato M.-p.Turpault INRAE BEFF-54000NancyFrance UMR 7359 GeoRessourcesFaculte des Sciences-Campus des Aiguillettes54506Vandoeuvre Les NancyFrance EcoSustain Environmental Engineering OfficeResearch and DevelopmentKanfen57330France

The increase in the frequency and intensity of drought events expected in the coming decades in Western Europe may disturb forest biogeochemical cycles and create nutrient deficiencies in trees.One possible origin of nutrient deficiency is the disturbance of the partitioning of the green leaf pool during the leaf senescence period between resorption,foliar leaching and senesced leaves.However,the effects of drought events on this partitioning and the consequences for the maintenance of tree nutrition are poorly documented.An experiment in a beech forest in Meuse(France)was conducted to assess the effect of drought events on nutrient canopy exchanges and on the partitioning of the green leaf pool during the leaf senescence period.The aim was to identify potential nutritional consequences of droughts for trees.Monitoring nutrient dynamics,including resorption,chemistry of green and senesced leaves,foliar absorption and leaching in mature beech stands from 2012 to 2019 allowed us to compare the nutrient exchanges for three nondry and three dry years(i.e.,with an intense drought event during the growing season).During dry years,we observed a decrease by almost a third of the potassium(K)partitioning to resorption(i.***.resorption efficiency),thus reducing the K reserve in trees for the next growing season.This result suggests that with the increased drought frequency and intensity expected for the coming decades,there will be a risk of potassium deficiency in trees,as already observed in a rainfall exclusion experiment on the same study site.Reduced foliar leaching and higher parititioning to the senesced leaves for K and phosphorus(p)were also observed.In addition,a slight increase in nitrogen(N)resorption efficiency occurred during dry years which is more likely to improve tree nutrition.The calcium(Ca)negative resorption decreased,with no apparent consequence in our study site.Our results show that nutrient exchanges in the canopy and the partitioning of the green leaf pool can be modified by drought events,and may

关键词： Natural drought Beech forest Canopy Resorption Foliar leaching Senesced leaves Nutrition

Examining the“revisability”benefit of hip resurfacing arthroplasty

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World journal of Orthopedics 2024年第6期15卷 554-559页

作者： jose George Adam j Taylor Thomas p Schmalzried Department of Orthopedics Harbor UCLA Medical CenterTorranceCA 90509United States

BACKGROUND Hip resurfacing arthroplasty(HRA)is an alternative to total hip arthroplasty(THA)that is typically reserved for young active patients because it preserves bone.However,the benefits of HRA only hold true if conversion THA after failed HRA provides acceptable outcomes.AIM To compare patient reported outcomes for conversion THA after HRA failure to primary THA.METHODS A retrospective review of 36 patients(37 hips)that underwent conversion THA for failed HRA between October 2006 and May 2019 by a single surgeon was performed.patient reported outcomes[modified Harris Hip Score(mHHS),University of California Los Angeles(UCLA)activity score]were obtained via an email-based responder-anonymous survey.Outcomes were compared to normative data of a primary THA cohort with similar demographics.Subgroup analysis was performed comparing outcomes of conversion THA for adverse local tissue reaction(ALTR)vs all other causes for failure.RESULTS The study group had a lower mHHS than the control group(81.7±13.8 vs 90.2±11.6,pps had similar UCLA activity levels(7.5±2.3 vs 7.2±1.6,p=0.51).patients that underwent conversion for non-ATLR causes had similar mHHS(85.2±11.5 vs 90.2±11.6,p=0.11)and higher UCLA activity levels(8.5±1.8 vs 7.2±1.6,ppared to the control group.patients that underwent conversion for ATLR had worse mHHS(77.1±14.5 vs 90.2±11.6,pp=0.05)when compared to the control group.CONCLUSION patient outcomes equivalent to primary THA can be achieved following HRA conversion to THA.However,inferior outcomes were demonstrated for ALTR-related HRA failure.patient selection and perhaps further studies examining alternative HRA bearing surfaces should be considered.

关键词： Total hip arthroplasty Hip resurfacing arthroplasty Conversion total hip arthroplasty Adverse local tissue reaction patient reported outcome measures

Laser-induced graphene-coated wearable smart textile electrodes for biopotentials signal monitoring

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Frontiers of Materials Science 2024年第1期18卷 95-111页

作者： C.M.Vidhya Yogita Maithani Sakshi Kapoor j.p.Singh Department of physics Indian Institute of Technology DelhiHauz KhasNew Delhi 110016India

This paper describes how to produce a wearable dry electrode at a reasonable cost and how to use it for the monitoring of biopotentials in electrocardiography.Smart textiles in wearable technologies have made a great advancement in the health care management and living standards of humans.Graphene was manufactured using the low-cost single-step process,laser ablation of polyimide,a commercial polymer.Graphene dispersions were made using solvent isopropyl alcohol which has low boiling point,nontoxicity,and environmental friendliness.After successive coating of the graphene dispersion on the cotton fabric to make it conductive,the sheet resistance of the resulting fabric dropped to 3% of its initial value.The laser-induced graphene(LIG)cotton dry electrodes thus manufactured are comparable to Ag/AgCl wet electrodes in terms of the skin-to-electrode impedance,measuring between 78.0 and 7.2 kΩ for the frequency between 40 Hz and 1 kHz.The LIG cotton electrode displayed a signal-to-noise ratio of 20.17 dB.Due to its comfort,simplicity,and good performance over a longer period of time,the textile electrode appears suited for medical applications.

关键词： biopotential electrocardiogram electromyogram flexible electrode textile porous graphene

Outcomes following minimally invasive dorsal cheilectomy for hallux rigidus:A systematic review

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World journal of Orthopedics 2024年第6期15卷 585-592页

作者： Katherine Esser james j Butler Mackenzie Roof Nathaniel p Mercer Michael C Harrington Alan p Samsonov Andrew j Rosenbaum john G Kennedy Department of Orthopaedic Surgery University of Toledo Medical Center University of Toledo College of Medicine and Life SciencesToledoOH 43614United States Department of Orthopedic Surgery NYU Langone HealthNew YorkNY 10002United States Department of Orthopedic Surgery Albany Medical CenterAlbanyNY 12208United States

BACKGROUND Cheilectomy of the 1^(st)metatarsophalangeal joint(MTpj)is one of the most common procedures for the management of hallux rigidus.However,there is no consensus regarding outcomes following minimally invasive dorsal cheilectomy(MIDC)for the management of hallux rigidus.AIM To evaluate outcomes following MIDC for the management of hallux rigidus.METHODS During November 2023,the pubMed,EMBASE and Cochrane Library databases were systematically reviewed to identify clinical studies examining outcomes following MIDC for the management of hallux rigidus.RESULTS Six studies were included.In total,348 patients(370 feet)underwent MIDC for hallux rigidus at a weighted mean follow-up of 37.9±16.5 months.The distribution of patients by Coughlin and Shurna's classification was recorded in 4 studies as follows:Ⅰ(58 patients,27.1%),Ⅱ(112 patients,52.3%),Ⅲ(44 patients,20.6%).Three studies performed an additional 1^(st)MTpj arthroscopy and debridement following MIDC.Retained intra-articular bone debris was observed in 100%of patients in 1 study.The weighted mean American orthopedic foot and ankle society score improved from a preoperative score of 68.9±3.2 to a postoperative score of 87.1.The complication rate was 8.4%,the most common of which was persistent joint pain and stiffness.Thirty-two failures(8.7%)were observed.Thirty-three secondary procedures(8.9%)were performed at a weighted mean time of 8.6±3.2 months following the index procedure.CONCLUSION This systematic review demonstrated improvements in subjective clinical outcomes together with a moderate complication rate following MIDC for the management of hallux rigidus at short-term follow-up.A moderate reoperation rate at short-term follow-up was recorded.The marked heterogeneity between included studies and paucity of high quality comparative studies limits the generation of any robust conclusions.

关键词： Minimally invasive dorsal cheilectomy Hallux rigidus The first metatarsophalangeal joint Cheilectomy Minimally invasive surgery

Impact of device resistances in the performance of graphene‑based terahertz photodetectors

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Frontiers of Optoelectronics 2024年第2期17卷 87-97页

作者： O.Castelló Sofía M.López Baptista K.Watanabe T.Taniguchi E.Diez j.E.Velázquez-pérez Y.M.Meziani j.M.Caridad j.A.Delgado-Notario Department of Applied physics University of Salamanca37008 SalamancaSpain Unidad de Excelencia en Luz y Materia Estructurada(LUMES) University of Salamanca37008 SalamancaSpain Research Center for Electronic and Optical Materials National Institute for Materials Science1-1 NamikiTsukuba 305-0044Japan Research Center for Materials Nanoarchitectonics National Institute for Materials Science1-1 NamikiTsukuba 305-0044Japan Nanotechnology Group USAL-NanolabUniversity of Salamanca37008 SalamancaSpain

In recent years,graphene field-effect-transistors(GFETs)have demonstrated an outstanding potential for terahertz(THz)photodetection due to their fast response and high-sensitivity.Such features are essential to enable emerging THz applications,including 6G wireless communications,quantum information,bioimaging and security.However,the overall performance of these photodetectors may be utterly compromised by the impact of internal resistances presented in the device,so-called access or parasitic resistances.In this work,we provide a detailed study of the influence of internal device resistances in the photoresponse of high-mobility dual-gate GFET detectors.Such dual-gate architectures allow us to fine tune(decrease)the internal resistance of the device by an order of magnitude and consequently demonstrate an improved responsivity and noise-equivalent-power values of the photodetector,respectively.Our results can be well understood by a series resistance model,as shown by the excellent agreement found between the experimental data and theoretical calculations.These findings are therefore relevant to understand and improve the overall performance of existing high-mobility graphene photodetectors.

关键词： Graphene THz photodetector Field-effect transistor plasmonic

HDpairFinder:A data processing platform for hydrogen/deuterium isotopic labeling-based nontargeted analysis of trace-level amino-containing chemicals in environmental water

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journal of Environmental Sciences 2024年第2期136卷 583-593页

作者： Tingting Zhao Kristin Carroll Caley B.Craven Nicholas j.p.Wawryk Shipei Xing jian Guo Xing-Fang Li Tao Huan Department of Chemistry Faculty of ScienceUniversity of British ColumbiaVancouver Campus2036 Main MallVancouverBritish ColumbiaV6T 1Z1Canada Division of Analytical and Environmental Toxicology Department of Laboratory Medicine and PathologyFaculty of Medicine and DentistryUniversity of AlbertaEdmontonAlberta T6G 2G3Canada

The combination of hydrogen/deuterium(H/D)formaldehyde-based isotopic methyl labeling with solid-phase extraction and high-performance liquid chromatography–high resolution mass spectrometry(HpLC-HRMS)is a powerful analytical solution for nontargeted analysis of trace-level amino-containing chemicals in water samples.Given the huge amount of chemical information generated in HpLC-HRMS analysis,identifying all possible H/Dlabeled amino chemicals presents a significant challenge in data processing.To address this,we designed a streamlined data processing pipeline that can automatically extract H/D-labeled amino chemicals from the raw HpLC-HRMS data with high accuracy and efficiency.First,we developed a cross-correlation algorithm to correct the retention time shift resulting from deuterium isotopic effects,which enables reliable pairing of H-and D-labeled peaks.Second,we implemented several bioinformatic solutions to remove false chemical features generated by in-source fragmentation,salt adduction,and natural13C isotopes.Third,we used a data mining strategy to construct the AMINES library that consists of over 38,000 structure-disjointed primary and secondary amines to facilitate putative compound annotation.Finally,we integrated these modules into a freely available R program,HDpairFinder.R.The rationale of each module was justified and its performance tested using experimental H/D-labeled chemical standards and authentic water samples.We further demonstrated the application of HDpairFinder to effectively extract N-containing contaminants,thus enabling the monitoring of changes of primary and secondary N-compounds in authentic water samples.HDpairFinder is a reliable bioinformatic tool for rapid processing of H/D isotopic methyl labeling-based nontargeted analysis of water samples,and will facilitate a better understanding of N-containing chemical compounds in water.

关键词： Isotope labeling Nontargeted analysis Reactive N-compounds HpLC-HRMS Source water

Background removal from global auroral images:Data-driven dayglow modeling

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Earth and planetary physics 2024年第1期8卷 247-257页

作者： A.Ohma M.Madelaire K.M.Laundal j.p.Reistad S.M.Hatch S.Gasparini S.j.Walker Birkeland Centre for Space Science Department of Physics and TechnologyUniversity of BergenBergenNorway

Global images of auroras obtained by cameras on spacecraft are a key tool for studying the near-Earth environment.However,the cameras are sensitive not only to auroral emissions produced by precipitating particles,but also to dayglow emissions produced by photoelectrons induced by sunlight.Nightglow emissions and scattered sunlight can contribute to the background signal.To fully utilize such images in space science,background contamination must be removed to isolate the auroral signal.Here we outline a data-driven approach to modeling the background intensity in multiple images by formulating linear inverse problems based on B-splines and spherical harmonics.The approach is robust,flexible,and iteratively deselects outliers,such as auroral emissions.The final model is smooth across the terminator and accounts for slow temporal variations and large-scale asymmetries in the dayglow.We demonstrate the model by using the three far ultraviolet cameras on the Imager for Magnetopause-to-Aurora Global Exploration(IMAGE)mission.The method can be applied to historical missions and is relevant for upcoming missions,such as the Solar wind Magnetosphere Ionosphere Link Explorer(SMILE)mission.

关键词： aurora dayglow modeling global auroral images far ultraviolet images dayglow removal

Collisionless shock acceleration of protons in a plasma slab produced in a gas jet by the collision of two laser-driven hydrodynamic shockwaves

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Matter and Radiation at Extremes 2024年第2期9卷 12-25页

作者： j.-R.Marquès L.Lancia p.Loiseau p.Forestier-Colleoni M.Tarisien E.Atukpor V.Bagnoud C.Brabetz F.Consoli j.Domange F.Hannachi p.Nicolaï M.Salvadori B.Zielbauer LULI CNRSÉcole PolytechniqueCEASorbonne UniversitéInstitut Polytechnique de Paris91128 Palaiseau CedexFrance CEA DAMDIF91297 Arpajon CedexFrance Universitéparis-Saclay CEALMCE91680 Bruyères-le-ChatelFrance CENBG CNRS-IN2P3Universitéde Bordeaux33175 Gradignan CedexFrance GSI Helmholtzzentrum für Schwerionenforschung GmbH Planckstraße 164291 DarmstadtGermany University of Darmstadt Schloßgartenstr.764289 DarmstadtGermany ENEA Fusion and Technologies for Nuclear Safety Department C.R.FrascatiVia Enrico Fermi 45FrascatiRomeItaly CELIA Universitéde Bordeaux–CNRS–CEA33405 TalenceFrance Universitéparis-Saclay CEALIDYL91191 Gif-sur-YvetteFrance

We have recently proposed a new technique of plasma tailoring by laser-driven hydrodynamic shockwaves generated on both sides of a gas jet[Marquès et al.,phys.plasmas 28,023103(2021)].In a continuation of this numerical work,we study experimentally the influence of the tailoring on proton acceleration driven by a high-intensity picosecond laser in three cases:without tailoring,by tailoring only the entrance side of the picosecond laser,and by tailoring both sides of the gas jet.Without tailoring,the acceleration is transverse to the laser axis,with a low-energy exponential spectrum,produced by Coulomb explosion.When the front side of the gas jet is tailored,a forward acceleration appears,which is significantly enhanced when both the front and back sides of the plasma are tailored.This forward acceleration produces higher-energy protons,with a peaked spectrum,and is in good agreement with the mechanism of collisionless shock acceleration(CSA).The spatiotemporal evolution of the plasma profile is characterized by optical shadowgraphy of a probe beam.The refraction and absorption of this beam are simulated by post-processing 3D hydrodynamic simulations of the plasma tailoring.Comparison with the experimental results allows estimation of the thickness and near-critical density of the plasma slab produced by tailoring both sides of the gas jet.These parameters are in good agreement with those required for CSA.

关键词： acceleration hydrodynamic collision