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Science China(Technological Sciences) 2024年第2期67卷 597-607页

作者： WU Xiao jiang HongJie LI WangYun LIU ChongYu huang HongFeng LIU ShuHui WEI LiLi School of Material Science and Engineering Guilin University of Technology Guilin 541004China Key Laboratory of New Processing Technology for Nonferrous Metal&Materials Ministry of EducationGuilin University of Technology Guilin 541004China School of Mechanical and Electrical Engineering Guilin University of Electronic TechnologyGuilin 541004China

The NiTip/1060Al composites were prepared using a pre-aging and friction stir method(FSP)to enhance the low-temperature damping performance of the aluminum alloy and accommodate various service *** bonding between NiTi particles and the 1060Al matrix is well established after FSP,and no new phases are formed in the *** phasetransformation peak temperature of NiTip/1060Al composites gradually shifts to lower temperatures with increased aging temperature of NiTi *** room temperature,the 550℃-NiTip/1060Al composite exhibits superior damping performance,with an internal friction value 144%higher than that of the FSP-1060Al ***,at-91℃,the 650℃-NiTip/1060Al composite demonstrates better damping performance,with an internal friction value 158%higher than that of the FSP-1060Al *** NiTip/1060Al composites exhibit the internal friction peak of NiTi phase-transformation in the temperature range from-91℃to 60℃.This characteristic results in significantly better damping performance compared to the FSP-1060Al alloy and other high-damping aluminum matrix composites.

关键词： NiTi particle aluminum matrix composites phase transformation damping behavior friction stir processing

Strong ferroelectric and luminescence properties of 0-3 type 0.8BaTiO_(3)-0.2CaTiO_(3):Pr^(3+)composite ceramics prepared by cold sintering process

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Journal of Advanced Ceramics 2024年第7期13卷 1002-1010页

作者： Xiaocui Rao Xueling Yang Renbing Sun Peng Du Hai jiang Yao huang Laihui Luo Department of Microelectronics Science and Engineering School of Physical Science and TechnologyNingbo UniversityNingbo 315211China College of Materials Science and Engineering Ningbo University of TechnologyNingbo 315016China

0-3 type ferroelectric-phosphor composite ceramics cannot be prepared by the traditional solid-state sintering(SSS)method due to the strong chemical reaction between ferroelectrics and phosphors during high-temperature *** cold sintering process(CSP)may solve this issue by densifying ceramics at ultralow sintering *** this work,dense 0-3 type 0.8BaTiO3-0.2CaTiO3:Pr^(3+)(0.8BT-0.2CT:Pr^(3+))binary composite ceramics were fabricated at an ultralow temperature of 225℃via CSP with the Ba(OH)2·8H2O hydrated *** effects of the Ba(OH)2·8H2O content,sintering temperature,and sintering time on the microstructure and densification of the ceramics were *** density of the composite ceramics prepared by the optimized sintering parameters reaches 89%.Both energy-dispersive X-ray(EDX)spectroscopy and X-ray diffraction(XRD)confirm the existence of BT and CT:Pr^(3+)phases in the prepared ceramics.A strong ferroelectric performance is obtained,and the luminescent properties of CT:Pr^(3+)are preserved for the ***,the 0.8BT-0.2CT:Pr^(3+)composite ceramics prepared by CSP have stronger photoluminescence and photo-stimulated luminescence than their counterparts prepared by cold sintering assistance(CSA)and SSS ***,CSP is a promising method for combining luminescent and ferroelectric properties into 0-3 type composite ceramics.

关键词： single-step densification cold sintering composite ceramics ferroelectric luminescence

Physically modulated phytoplankton production and export at submesoscales in the oligotrophic South China Sea Basin

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Science China Earth Sciences 2024年第8期67卷 2681-2698页

作者： Zhonghua ZHAO Mengdi XU Bangqin huang Wenfang LU Hongshuai QI Feng CAI Yuwu jiang State Key Laboratory of Marine Environmental Science Xiamen UniversityXiamen 361102China College of Ocean and Earth Sciences Xiamen UniversityXiamen 361102China Fujian Provincial Key Laboratory for Coastal Ecology and Environmental Studies Xiamen UniversityXiamen 361102China National Observation and Research Station for the Taiwan Strait Marine Ecosystem Xiamen UniversityXiamen 361102China School of Marine Sciences Sun Yat-Sen UniversitySouthern Marine Science and Engineering Guangdong Laboratory(Zhuhai)Zhuhai 519000China Laboratory of Ocean and Coast Geology Third Institute of OceanographyMinistry of Natural ResourcesXiamen 361005China

Oceanic submesoscales can significantly influence phytoplankton production and export owing to their similar timescales of *** on two-year Biogeochemical Argo(BGC-Argo) observations,this study investigated the development of submesoscale instabilities,particularly symmetric and mixed-layer baroclinic instabilities,and their impacts on biological production and export in the oligotrophic South China Sea *** the northern basin,near-surface winter blooms consistently cooccurred with seasonally deepened mixed ***,significantly stronger and weaker winter blooms were observed over two consecutive winters within the BGC-Argo observation *** the first winter,symmetric-instability-induced upward nutrient entrainment played a crucial role in initiating the strong winter bloom in early December,when the mixed layer was approximately 20–30 m shallower than the *** bloom occurred approximately 20–30 days earlier than that anticipated owing to the contact between the seasonally deepened mixed layer and mesoscale-cyclone-induced uplifted *** symmetric instability also facilitated the export of fixed phytoplankton carbon from the surface to deeper ***,during the second winter,remarkably intense mixed-layer baroclinic instability associated with an intense mesoscale anticyclone led to more significant shoaling of the mixed layer compared to the nutricline,thus increasing the vertical distance between the two *** this condition,upward nutrient injection,phytoplankton bloom,and carbon export were *** contrast,the BGC-Argo float in the central basin revealed significantly inhibited seasonality of phytoplankton biomass and submesoscale instabilities compared to those in the northern basin,primarily owing to the significantly shallower winter mixed layer.

关键词： Submesoscale instability Phytoplankton Nutrient transport BGC-Argo South China Sea

Spatiotemporal characteristics and driving mechanisms of land use/land cover(LULC)changes in the Jinghe River Basin,China

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Journal of Arid Land 2024年第1期16卷 91-109页

作者： WANG Yinping jiang Rengui YANG Mingxiang XIE Jiancang ZHAO yong LI Fawen LU Xixi State Key Laboratory of Eco-hydraulics in Northwest Arid Region of China Xi'an University of TechnologyXi'an 710048China State Key Laboratory of Simulation and Regulation of Water Cycle in River Basin China Institute of Water Resources and Hydropower ResearchBeijing 100038China State Key Laboratory of Hydraulic Engineering Simulation and Safety Tianjin UniversityTianjin 300072China Department of Geography National University of SingaporeSingapore 117570Singapore

Understanding the trajectories and driving mechanisms behind land use/land cover(LULC)changes is essential for effective watershed planning and *** study quantified the net change,exchange,total change,and transfer rate of LULC in the Jinghe River Basin(JRB),China using LULC data from 2000 to *** trajectory analysis,knowledge maps,chord diagrams,and standard deviation ellipse method,we examined the spatiotemporal characteristics of LULC *** further established an index system encompassing natural factors(digital elevation model(DEM),slope,aspect,and curvature),socio-economic factors(gross domestic product(GDP)and population),and accessibility factors(distance from railways,distance from highways,distance from water,and distance from residents)to investigate the driving mechanisms of LULC changes using factor detector and interaction detector in the geographical detector(Geodetector).The key findings indicate that from 2000 to 2020,the JRB experienced significant LULC changes,particularly for farmland,forest,and *** the study period,LULC change trajectories were categorized into stable,early-stage,late-stage,repeated,and continuous change *** the stable change type,the late-stage change type predominated the LULC change trajectories,comprising 83.31% of the total change *** period 2010-2020 witnessed more active LULC changes compared to the period *** LULC changes exhibited a discrete spatial expansion trend during 2000-2020,predominantly extending from southeast to northwest of the *** driving factors on LULC changes included slope,GDP,and distance from *** interaction detection results imply either bilinear or nonlinear enhancement for any two driving factors impacting the LULC changes from 2000 to *** comprehensive understanding of the spatiotemporal characteristics and driving mechanisms of LULC changes offers valuable insights for the planning and sustainable management

关键词： land use/land cover(LULC)changes driving mechanisms trajectory analysis geographical detector(Geodetector) Grain for Green Project Jinghe River Basin

Straw addition increases enzyme activities and microbial carbon metabolism activities in bauxite residue

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Journal of Environmental Sciences 2024年第1期135卷 332-344页

作者： Hao Wu Wei Sun Feng Zhu Yifan jiang Shiwei huang Johnvie Goloran Shengguo Xue School of Minerals Processing and Bioengineering Central South UniversityChangsha 410083China School of Metallurgy and Environment Central South UniversityChangsha 410083China School of Environment and Science Griffith UniversityBrisbaneQLD 4072Australia

Recovery of microbial functions is one of the critical processes in the nutrient cycling of bauxite residue for improving *** is considered to be effective to increase microbial diversity and drive the development of the microbial community,but its effect on microbial carbon metabolism has not been *** present study evaluated the effects of phosphogypsum(PG),straw(SF)and phosphogypsum plus straw(PGSF)on physicochemical properties,enzyme activities,and microbial carbon metabolism activities in bauxite *** 180 days incubation,PG,SF and PGSF treatment significantly reduced the residue pH from 10.85 to 8.64,9.39 and 8.06,*** to CK treatment,SF treatment significantly increased the content of total organic carbon(TOC)and organic carbon fractions(DOC,MBC,EOC,and POC).In addition,straw addition significantly increased glucosidase,cellulose,urease,and alkaline phosphatase by 7.2-9.1 times,5.8-7.1 times,11.1-12.5 times,and 1.1-2.2 times,*** Biolog results showed that straw addition significantly increased microbial metabolic activity(AWCD)and diversity in bauxite *** analysis indicated total nitrogen(TN)and carbon fractions(POC,MBC and DOC)were the most important environmental factors affecting microbial metabolic activity and diversity in bauxite *** findings provided us with a biogeochemical perspective to reveal soil formation in bauxite residue and suggested that nutrient supplement and regulation of salinity-alkalinity benefit the establishment of microbial communities and functions in bauxite residue.

关键词： Bauxite residue Labile organic carbon fractions Enzyme activities Community-level physiological profiles Soil formation in bauxite residue

Preparation and Tribological Properties of Onion-like Carbon/Waterborne Polyurethane Coatings

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China Petroleum Processing & Petrochemical Technology 2024年第2期26卷 108-120页

作者： Fei Xingpeng jiang Wuhao Wen Maosheng Xu yong Hu Kunhong Hu Enzhu Department of Energy Materials and Chemical Engineering Hefei UniversityHefei 230601China Anhui Province Key Laboratory of Critical Friction Pair for Advanced Equipment Hefei 230088China

Rice husk powder was used as a carbon source in a high-temperature carbonization reaction for the production of rice husk ash(RHA).Under the catalysis of ferric nitrate,onion-like carbon(OLC)nanomaterial with a particle size of approximately 200 nm was successfully prepared and incorporated into waterborne polyurethane(WPU).The tribological properties of the coatings were determined using a controlled-atmosphere tribometer(WMT-2E)under dry-friction *** the friction test,the friction mechanism was investigated by characterizing the abrasive spot surfaces of the test samples using 3D laser microscopy and scanning electron microscopy/energy dispersive *** final results demonstrated that the thermal stability of WPU composite coatings containing various concentrations of OLC nanoparticles was significantly enhanced,binding forces between coatings and steel sheets increased,and hardness improved compared to pure WPU *** tests revealed a notable enhancement in the anti-wear properties of WPU coatings due to the presence of OLC ***,the wear rate of the 1.5%OLC/WPU coating was reduced by 45.3%.The coating’s anti-wear mechanism was attributed to the improvement in the mechanical properties of WPU due to OLC,as well as OLC’s participation in the formation of a transfer film under induced friction,which protected the matrix.

关键词： biomass carbon onion-like carbon waterborne polyurethane wear transfer films

Searching for the optimal precondition procedure for mesenchymal stem/stromal cell treatment:Facts and perspectives

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World Journal of Stem Cells 2024年第6期16卷 615-618页

作者： Yu-Dong Zhao yong-Can huang Wei-Shi Li Department of Orthopedic Peking University Third HospitalBeijing 100191China Shenzhen Engineering Laboratory of Orthopaedic Regenerative Technologies Orthopaedic Research CenterPeking University Shenzhen HospitalShenzhen 518036Guangdong ProvinceChina

Mesenchymal stem/stromal cells are potential optimal cell sources for stem cell therapies,and pretreatment has proven to enhance cell vitality and *** a recent publication,Li et al explored a new combination of pretreatment ***,we present an editorial to comment on their work and provide our view on mesenchymal stem/stromal cell precondition.

关键词： Mesenchymal stem cell Precondition Hypoxia Inflammation

Microstructure and room temperature fracture toughness of Nb-Si-based alloys with Sr addition

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Rare Metals 2024年第8期43卷 3904-3912页

作者： yong-Lin huang Li-Na Jia Bin Kong Yue-Ling Guo Na Wang School of Materials Science and Engineering Beihang UniversityBeijing 100191China

Nb-Si-based alloys show great potential to surpass the widely used Ni-based *** element Sr is widely applied in aluminum and magnesium alloys,but reports about the effects of Sr on Nb-Si-based alloys are quite ***,Nb-Si-based alloys with nominal compositions of Nb-15Si-24Ti-4Cr-2Al-2Hf-0/0.05/0.15Sr(at%)were prepared by directional solidification and heat *** microstructural characterization and room temperature fracture toughness of Nb-Si-based alloy were systematically *** show that all these alloys consist of Nb_5Si_3 phase embedded within Nb solid solution(Nb_(ss)) *** Nb_(5)Si_(3) phase becomes refined and more discontinuous after adding minor *** for the fracture toughness,0.05 at% and 0.15 at% Sr additions do not cause significant *** discontinuous and refining mechanism of Sr element was studied,and the analysis of toughness decreasing with Sr addition reveals that the size of Nb_(ss) phase plays a crucial role in determining the fracture toughness.

关键词： Nb-Si alloy Refinement Discontinuous Fracture toughness Nb_(ss)

Screening the optimal Co_(x)/CeO_(2)(110)(x=1–6)catalyst for methane activation in coalbed gas

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International Journal of Coal Science & Technology 2024年第3期11卷 256-271页

作者： Li’nan huang Danyang Li Lei jiang Zhiqiang Li Dong Tian Kongzhai Li Engineering Research Center of Metallurgical Energy Conservation and Emission Reduction Ministry of EducationKunming University of Science and TechnologyKunming650093China Faculty of Metallurgical and Energy Engineering Kunming University of Science and TechnologyKunming650093China State Key Laboratory of Complex Nonferrous Metal Resources Clean Utilization Kunming University of Science and TechnologyKunming650093China

The challenges posed by energy and environmental issues have forced mankind to explore and utilize unconventional energy *** is imperative to convert the abundant coalbed gas(CBG)into high value-added products,i.e.,selective and efficient conversion of methane from *** activation,known as the“holy grail”,poses a challenge to the design and development of *** structural complexity of the active metal on the carrier is of particular *** this work,we have studied the nucleation growth of small Co clusters(up to Co_(6))on the surface of CeO_(2)(110)using density functional theory,from which a stable loaded Co/CeO_(2)(110)structure was selected to investigate the methane activation *** the relatively small size of the selected Co clusters,the obtained Co_(x)/CeO_(2)(110)exhibits interesting *** optimized Co_(5)/CeO_(2)(110)structure was selected as the optimal structure to study the activation mechanism of methane due to its competitive electronic structure,adsorption energy and binding *** energy barriers for the stepwise dissociation of methane to form CH3^(*),CH2^(*),CH^(*),and C^(*)radical fragments are 0.44,0.55,0.31,and 1.20 eV,respectively,indicating that CH^(*)dissociative dehydrogenation is the rate-determining step for the system under investigation *** fundamental study of metal-support interactions based on Co growth on the CeO_(2)(110)surface contributes to the understanding of the essence of Co/CeO_(2) catalysts with promising catalytic *** provides theoretical guidance for better designing the optimal Co/CeO_(2) catalyst for tailored catalytic reactions.

关键词： Co cluster growth Ce-based catalysts Methane activation DFT

Supramolecular polymer-based gel fracturing fluid with a double network applied in ultra-deep hydraulic fracturing

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Petroleum Science 2024年第3期21卷 1875-1888页

作者： yong-Ping huang yong Hu Chang-Long Liu Yi-Ning Wu Chen-Wei Zou Li-Yuan Zhang Ming-Wei Zhao Cai-Li Dai School of Petroleum Engineering China University of Petroleum(East China)Qingdao266580ShandongPR China Shandong Key Laboratory of Oilfield Chemistry China University of Petroleum(East China)Qingdao 266580ShandongPR China SINOPEC Petroleum Exploration and Production Research Institute Beijing102206PR China CNOOC China Co Ltd Tianjin BranchTianjin300459PR China

A gel based on polyacrylamide,exhibiting delayed crosslinking characteristics,emerges as the preferred solution for mitigating degradation under conditions of high temperature and extended shear in ultralong *** viscosity/viscoelasticity of the fracturing fluid was required to maintain excellent proppant suspension properties before *** into account both the cost and the potential damage to reservoirs,polymers with lower concentrations and molecular weights are generally *** this work,the supramolecular action was integrated into the polymer,resulting in significant increases in the viscosity and viscoelasticity of the synthesized supramolecular polymer *** double network gel,which is formed by the combination of the supramolecular polymer system and a small quantity of Zr-crosslinker,effectively resists temperature while minimizing permeability damage to the *** results indicate that the supramolecular polymer system with a molecular weight of(268—380)×10^(4)g/mol can achieve the same viscosity and viscoelasticity at 0.4 wt%due to the supramolecular interaction between polymers,compared to the 0.6 wt%traditional polymer(hydrolyzed polyacrylamide,molecular weight of 1078×10^(4)g/mol).The supramolecular polymer system possessed excellent proppant suspension properties with a 0.55 cm/min sedimentation rate at 0.4 wt%,whereas the0.6 wt%traditional polymer had a rate of 0.57 cm/*** comparison to the traditional gel with a Zrcrosslinker concentration of 0.6 wt%and an elastic modulus of 7.77 Pa,the double network gel with a higher elastic modulus(9.00 Pa)could be formed only at 0.1 wt%Zr-crosslinker,which greatly reduced the amount of residue of the fluid after *** viscosity of the double network gel was66 m Pa s after 2 h shearing,whereas the traditional gel only reached 27 m Pa s.

关键词： Ultra-deep reservoir Gel fracturing fluid Double network Supramolecular polymer system Proppant suspension property