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Elevated CO_(2) increases soil redox potential by promoting root radial oxygen loss in paddy field

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Journal of Environmental Sciences 2024年第2期136卷 11-20页

作者： Jie Li Han Zhang Wenyi Xie Cheng Liu Xiaoyu Liu Xuhui Zhang Lianqing Li Genxing Pan Institute of Resource Ecosystem and Environment of AgricultureNanjing Agricultural UniversityNanjing 210095China College of Agriculture Nanjing Agricultural UniversityNanjing 210095China

Soil redox potential(Eh)plays an important role in the biogeochemical cycling of soil *** its effect soil process and nutrients'availability under elevated atmospheric CO_(2) concentration and warming has seldom been ***,in this study,a field experiment was used to elucidate the effect of elevated CO_(2) concentration and warming on soil Eh,redox-sensitive elements and root radial oxygen loss(ROL).We hypothesized elevated CO_(2) and warming could alter soil Eh by promoting or inhibiting *** found that soil Eh in the rhizosphere was significantly higher than that of *** CO_(2) enhanced soil Eh by 11.5%,which corresponded to a significant decrease in soil Fe^(2+)and Mn^(2+)*** elevated CO_(2),the concentration of Fe^(2+)and Mn^(2+)decreased by 14.7%and 13.7%,*** also found that elevated CO_(2) altered rice root aerenchyma structure and promoted rice root *** elevated CO_(2),rice root ROL increased by 79.5%and 112.2%for Yangdao 6 and Changyou 5,*** had no effect on soil Eh and rice root *** warming increased the concentration of Mn^(2+)and SO_(4)^(2-)by 4.9%and 19.3%,*** was a significant interaction between elevated CO_(2) and warming on Fe^(2+)and Mn^(2+).Under elevated CO_(2),warming had no effect on the concentration of Fe^(2+)but decreased Mn^(2+)concentration *** study demonstrated that elevated atmospheric CO_(2) in the future could increase soil Eh by promoting rice root ROL,which will alter some soil nutrients'availability,such as Fe^(2+)and Mn^(2+).

关键词： Atmospheric CO_(2)enrichment Global warming Soil redox potential FACE Rice root aerenchyma

Dynamic Crosslinked Phosphorescent Poly(vinyl alcohol)-Terpyridine Films with Enhanced Mechanical Properties and Tunable Shape Memory

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Chinese Journal of Polymer Science 2024年第10期42卷 1595-1601,I0015页

作者： Meng Wei Wei-Hao Feng Chen Yu Zhen-Yi Jiang Guang-Qiang Yin Wei Lu Tao Chen Key Laboratory of Advanced Marine Materials Ningbo Institute of Materials Technology and EngineeringChinese Academy of SciencesNingbo315201China School of Chemical Sciences University of Chinese Academy of SciencesBeijing100049China School of Materials Science and Chemical Engineering Ningbo UniversityNingbo315211China

Achieving versatile room temperature phosphorescence(RTP)materials,especially with tunable mechanical properties and shape memory is attractive and essential but rarely ***,a strategy was reported to realize multi-functional RTP films with multicolor fluorescence,ultralong afterglow,adjustable mechanical properties,and shape memory through the synergistic dynamic interaction of lanthanide(Ln~Ⅲ)-terpyridine coordination,borate ester bonds,and hydrogen bondings in a poly(vinyl alcohol)(PVA)*** varying the amount of borax,the mechanical properties of the films could be finely controlled due to the change of crosslinking degree of dynamic borate ester bonds in *** assembly and disassembly of borate ester bonds upon the trigger of borax and acid were applied as reversible linkage to achieve programmable shape memory *** addition,the films displayed both fascinating multicolor fluorescence and ultralong afterglow characteristics due to the presence of Ln III doping and confinement of terpyridine in *** study provides a new avenue to impart modulable mechanical strength and shape memory to RTP materials.

关键词： Room temperature phosphorescence materials Dynamic bonds Multicolor fluorescent Tunable mechanical properties Shape memory

An efficient scheme for accelerating the calculation of stacking fault energy in multi-principal element alloys

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Journal of Materials Science & Technology 2024年第8期175卷 204-211页

作者： Haoran Sun Zhigang Ding Hao Sun Junjun Zhou Ji-Chang Ren Qingmiao Hu Wei Liu School of Materials Science and Engineering Nanjing University of Science and TechnologyNanjing 210094China State Key Laboratory of Rare Earth Resource Utilization Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun 130022China Shenyang National Laboratory for Materials Science Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China

We present the High-Throughput Computing and Statistical Analysis(HCSA)scheme,which efficiently and accurately predicts the stacking fault energies(SFEs)of multi-principal element alloys(MPEAs).Our approach estimates the SFE of a single complex supercell by averaging numerous SFEs from small supercells,resulting in superior accuracy compared to traditional density functional theory(DFT)*** validate our scheme,we applied it to NiFe and Ni_(10)Co_(60)Cr_(25)W_(5)alloys,achieving an SFE error of only 11%,in contrast to the 45%error obtained from traditional DFT calculations for *** observed a strong correlation between the average SFEs of samples with the same valence electron concentration as that of the experimental *** scheme provides an efficient and reliable tool for predicting SFEs in MPEAs and holds the potential to significantly accelerate materials design and discovery processes.

关键词： Multi-principal element alloys Stacking fault energy Density functional theory High-throughput calculation

Atmospheric environment monitoring technology and equipment in China:A review and outlook

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Journal of Environmental Sciences 2023年第1期123卷 41-53页

作者： Youwen Sun Ting Yang Huaqiao Gui Xin Li Weigang Wang Jun Duan Shushuai Mao Hao Yin Bin Zhou Jianlei Lang Haijin Zhou Cheng Liu Pinhua Xie Key Laboratory of Environmental Optics and Technology Anhui Institute of Optics and Fine MechanicsHFIPSChinese Academy of SciencesHefei 230031China Department of Precision Machinery and Precision Instrumentation University of Science and Technology of ChinaHefei 230026China State Key Laboratory of Atmospheric Boundary Layer Physics and Atmospheric Chemistry Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing 100029China State Key Joint Laboratory of Environmental Simulation and Pollution Control College of Environmental Sciences and EngineeringPeking UniversityBeijing 100871China State Key Laboratory for Structural Chemistry of Unstable and Stable Species Institute of ChemistryChinese Academy of SciencesBeijing 100190China Key Laboratory of Beijing on Regional Air Pollution Control College of Environmental&Energy EngineeringBeijing University of TechnologyBeijing 100124China Shanghai Key Laboratory of Atmospheric Particle Pollution and Prevention(LAP3) Department of Environmental Science and EngineeringFudan UniversityShanghai 200438China Center for Excellence in Regional Atmospheric Environment Institute of Urban EnvironmentChinese Academy of SciencesXiamen 361021China Key Laboratory of Precision Scientific Instrumentation of Anhui Higher Education Institutes University of Science and Technology of ChinaHefei 230026China Anhui Province Key Laboratory of Polar Environment and Global Change University of Science and Technology of ChinaHefei 230026China

Accurate monitoring of the atmospheric environment and its evolution are important for understanding the sources,chemical mechanisms,and transport processes of air pollution and carbon emissions in China,and for regulatory and control *** study gives an overview of atmospheric environment monitoring technology and equipment in China and summarizes the major achievements obtained in recent *** has made great progress in the development of atmospheric environment monitoring technology and equipment with decades of *** manufacturing level of atmospheric environment monitoring equipment and the quality of products have steadily improved,and a technical&production system that can meet the requirements of routine monitoring activities has been *** is expected that domestic atmospheric environment monitoring technology and equipment will be able to meet future demands for routine monitoring activities in China and provide scientific assistance for addressing air pollution problems.

关键词： Atmospheric pollution Atmospheric environment Atmospheric monitoring Environmental instrument

Determination of global geodetic parameters using satellite laser ranging to Galileo,GLONASS,and BeiDou satellites

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Satellite Navigation 2024年第1期5卷 240-257页

作者： Xingxing Li Jiaqing Lou Yongqiang Yuan Jiaqi Wu Keke Zhang School of Geodesy and Geomatics Wuhan University129 Luoyu RoadWuhan430079HubeiChina

The new Global Navigation Satellite System(GNSS)satellites,including GLONASS,Galileo,and BeiDou system,are equipped with Laser Retroreflector Arrays(LRA)to support Satellite Laser Ranging(SLR)tracking,which contributes to the estimation of global geodetic *** this study,we estimate the global geodetic parameters using the SLR observations to GNSS satellites and also investigate the effects of different data processing strategies on the estimated Earth Rotation Parameters(ERP),geocenter motion,and terrestrial *** results indicate that setting range bias parameters for each satellite-station pair can effectively account for the satellite-specific biases induced by LRAs,leading to smaller Root Mean Square Errors(RMSE)of the post-fit SLR ***,estimating the range biases for each satellite-station pair improves the accuracy of the estimated station coordinates and *** also examine the impact of different arc lengths on the estimates of ERP,geocenter motion,and terrestrial *** results show that extending arc length can significantly reduce the formal error of *** 7-day strategy produces the smallest RMSEs of 473 microarcseconds and 495 microarcseconds for the estimated X-and Y-component of pole coordinates,and 52 microseconds for length-of-day,***,the estimated geocenter motion is less affected by the arc length,even the shortest 1-day arc strategy can capture the seasonal variations of geocenter motion in Z *** scale estimation,extending the arc length notably improves the accuracy of the estimated station coordinates and scale,but this advantage becomes less noticeable in longer *** 7-day solution also obtains the closet scale results compared to ITRF2014,with the RMSE of 2.10×10^(–9).

关键词： Satellite laser ranging GNSS Geodetic parameters Earth rotation parameters Geocenter motion Terrestrial scale

Multi-GNSS products and services at iGMAS Wuhan Innovation Application Center:strategy and evaluation

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Satellite Navigation 2022年第3期3卷 106-124,I0004页

作者： Xingxing Li Qingyun Wang Jiaqi Wu Yongqiang Yuan Yun Xiong Xuewen Gong Zhilu Wu School of Geodesy and Geomatics Wuhan University129 Luoyu RoadWuhan430079China

Over the past years the International Global Navigation Satellite System(GNSS)Monitoring and Assessment System(iGMAS)Wuhan Innovation Application Center(IAC)dedicated to exploring the potential of multi-GNSS signals and providing a set of products and *** contribution summarizes the strategies,achievements,and innovations of multi-GNSS orbit/clock/bias determination in iGMAS Wuhan *** the precise products and Real-Time Services(RTS)are evaluated and *** precise orbit and clock products have comparable accuracy with the precise products of the International GNSS Service(IGS)and *** multi-frequency code and phase bias products for Global Positioning System(GPS),BeiDou Navigation Satellite System(BDS),Galileo navigation satellite system(Galileo),and GLObal NAvigation Satellite System(GLONASS)are provided to support multi-GNSS and multi-frequency Precise Point Positioning(PPP)Ambiguity Resolution(AR).Compared with dual-frequency PPP AR,the time to first fix of triple-frequency solution is improved by 30%.For RTS,the proposed orbit prediction strategy improves the three dimensional accuracy of predicted orbit by 1 *** multi-thread strategy and high-performance matrix library are employed to accelerate the real-time orbit and clock *** results with respect to the IGS precise products show the high accuracy of RTS orbits and clocks,4–9 cm and 0.1–0.2 ns,*** real-time satellite corrections,real-time PPP solutions achieve satisfactory performance with horizontal and vertical positioning errors within 2 and 4 cm,respectively,and convergence time of 16.97 min.

关键词： iGMAS Wuhan Innovation Application Center GREAT software Precise orbit determination Precise clock estimation Observation-specific bias Precise point positioning Real-time service

Anomalous thermal expansion and enhanced magnetocaloric effect in<001>-textured Mn_(x)Fe_(5-x)Si_(3) alloys

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Rare Metals 2024年第5期43卷 2263-2274页

作者： Yong Gong Xue-Fei Miao Tapas Samanta Chris Taake Jun Liu Feng-Jiao Qian Yan-Yan Shao Yu-Jing Zhang Qing-Yong Ren Luana Caron Feng Xu MIIT Key Laboratory of Advanced Metallic and Intermetallic Materials Technology School of Materials Science and EngineeringNanjing University of Science and TechnologyNanjing210094China Department of Physics Bielefeld University33501BielefeldGermany College of Physics Nanjing University of Aeronautics and AstronauticsNanjing210016China Institute of High Energy Physics Chinese Academy of SciencesBeijing100049China Spallation Neutron Source Science Center Dongguan523803China Guangdong-Hong Kong-Macao Joint Laboratory for Neutron Scattering Science and Technology Dongguan523803China Department of Physics Bielefeld University33501BielefeldGermany Helmholtz-Zentrum Berlin für Materialien und Energie12489BerlinGermany

The development of zero and negative therma expansion(i.e.,ZTE and NTE)materials is of crucial importance to the control of undesirable thermal expansion for high-precision *** the present work,ZTE and NTE were obtained in directionally-solidified Mn_(x)Fe_(5-x)Si_(3)alloys with a strongtexture,in striking contrast to positive thermal expansion in their isotropic counterparts Magnetometry and in-situ X-ray diffraction(XRD)measurements were performed to uncover the origin of the anomalous thermal *** measurements indicate a strong easy-plane magnetocrystalline anisotropy in the textured samples,where the magnetic moments are aligned within the ab plane of the hexagonal structure Temperature-dependent XRD on the x=1 sample reveals a ZTE character in the ab plane that is coupled to a ferromagnetic *** a result,the macroscopic ZTE(~0.22×10^(-6)K^(-1))in the x=1 sample can be attributed to the microscopic magneto volume effect within the ab plane,which is realized by the introduction of the-textured ***,the competition between antiferromagnetic and ferromagnetic exchange coupling leads to NTE in textured x=1.5 and 2 ***,textured x=1 sample displays enhanced magnetocaloric properties as compared to the conventional counterparts with randomly-oriented *** this work demonstrates a new strategy toward the exploration of anomalous thermal expansion properties as well as the enhancement of magnetocaloric properties for materials with a strong magnetocrystalline anisotropy.

关键词： MnFeySis Magnetocaloric effect Magnetic phase transition Negative thermal expansion

Tree ring derived summer temperature variability over the past millennium in the western Himalayas of northern Pakistan

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Frontiers of Earth Science 2023年第4期17卷 1026-1036页

作者： Fayaz ASAD Haifeng ZHU Tabassum YASEEN Ru HUANG Mukund Palat RAO Department of Botany Bacha Khan University CharsaddaKhyber Dakhtun Khaw 24420Pakistan State Key Laboratory of Tibetan Plateau Earth System Resources and Environment(TPESRE)Institute of Tibetan Plateau ResearchChinese Academy of SciencesBeijing 100101China China Pakistan Joint Research Center on Earth Sciences CAS-HECIslamabad 45320Pakistan Centre de Recerca Ecològica i Aplicacions Forestals Barcelona 08193Spain Department of Plant Science University of California Davis(UC Davis)95616CaliforniaUSA Tree Ring Laboratory Lamont-Doherty Earth ObservatoryColumbia UniversityNY 10964USA

Long-term high resolution climate proxies are essential for understanding climate variability particularly,in regions such as the western Himalayas of northern Pakistan,where few long-term climate records are *** standard dendrochronological methods,an 1132-year(882 to 2013 C.E.)tree-ring chronology of Juniperus excelsa *** was established from the western Himalayas,northern Pakistan(WHNP).Tree growth was negatively and significantly(r=-0.65)correlated with the growing season(June-July)mean temperature,and positively and weakly(r=0.22)associated with *** inverse relationship of tree radial growth with temperature and positive association with precipitation demonstrated that forest growth is sensitive to high temperature related *** a reliable STD chronology and robust reconstruction model,a 928-year(1086 to 2013 C.E.)mean temperature reconstruction was developed for the WHNP using the substantial negative correlation between the summer temperature and standard tree ring-width *** to statistical validation,the reconstruction accounted for 41.6% of the climatic variation for the period of 1956-2013 *** *** extreme-warm periods occurred in 1093 C.E.(29.42℃)and extreme cold periods in 1088 C.E.(26.99℃)observed during the past 928 *** reconstruction's multi-taper method(MTM)spectral analysis reveals significant(p<0.05)2-3-year and 63.8-year *** the 2-3-year cycle occurred within the range of ENSO variation,which indicates that ENSO had an impact on the regional temperature in our studied area.

关键词： tree rings Juniperus excelsa dendrochronology reconstruction western Himalaya

Recent advances in the application of computational fluid dynamics in the development of rotary blood pumps

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Medicine in Novel Technology and Devices 2022年第4期16卷 237-249页

作者： Peng Wu Artificial Organ Technology Lab School of Mechanical and Electric EngineeringSoochow UniversitySuzhouJiangsuChina

In recent years,ventricular assist devices(VADs,also known as blood pumps)have gradually entered clinical practice and provide effective treatment for heart failure ***,adverse events related to mechanical blood damage in patients receiving the VAD treatment,were often reported and have become a major concern during the development of VADs,limiting their clinical and economic *** with bench and in-vivo testing,computational fluid dynamics(CFD)is flexible and inexpensive,offering the possibility to predict hemodynamics and mechanical blood damage in a purely numerical ***,CFD has become an important tool for the design,optimization and evaluation of blood *** stringent requirements of blood pumps require high fidelity ***,this article reviews the current state of the art in high-fidelity methodologies for simulating blood flow and blood damage for the development and evaluation of rotary blood pumps;design and optimization methods of rotatory blood pumps using CFD,as well as future challenges.

关键词： Computational fluid dynamics Blood pump Turbulence Hemodynamics Hemolysis Platelet activation Thrombosis Design and optimization