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Nighttime sap flow of Acacia mangium and its implications for nighttime transpiration and stem water storage

Journal of plant Ecology 2012年第3期5卷 294-304页

作者： Hua Wang ping Zhao Dirk Hölscher Quan Wang ping Lu Xi A.Cai xiao p.zeng South China Institute of Botany Chinese Academy of SciencesGuangzhou 510650China Institute of Forestry and pomology Beijing Academy of Agriculture and Forestry SciencesBeijing 100093China Research Center for Eco-Environmental Sciences Chinese Academy of SciencesBeijing 100085China Department of Tropical Silviculture and Forest Ecology University of Göttingen37077 GöttingenGermany Faculty of Agriculture Shizuoka UniversityShizuoka 422-8529Japan Energy Resources of Australia Ltd GPO Box 2394DarwinNorthern Territory0801Australia

Aims Nighttime sap flow of trees may indicate transpiration and/or recharge of stem water storage at *** paper deals with the water use of Acacia mangium at night in the hilly lands of subtropical South *** primary goal was to reveal and understand the nature of nighttime sap flow and its functional *** Granier’s thermal dissipation method was used to determine the nighttime sap flux of *** exchange system was used to estimate nighttime leaf transpiration and stomatal conductance of studied *** Findings Nighttimesap flowwas substantial and showed seasonal variation similar to the patterns of daytime sap flowin *** nighttime sap flow was higher in the less precipitation year of 2004(1122.4 mm)than in the more precipitation year of 2005(1342.5 mm)since more daytime transpiration and low soil water availability in the relatively dry 2004 can be the cause of more nighttime sap *** vapor pressure deficit and air temperature were significantly correlated with nighttime sap flow,they could only explain a small fraction of the variance in nighttime sap *** total accumulated water loss(E_(L))by transpiration of canopy leaves was only;2.6–8.5%of the total nighttime sap flow(E_(t))during the nights of July 17–18 and 18–19,***,it is likely that the nighttime sap flow was mainly used for refillingwater in the *** stem diameter at breast height,basal area and sapwood area explained much more variance of nighttime water recharge than environmental factors and other tree form features,such as tree height,stem length below the branch,and canopy *** contribution of nighttime water recharge to the total transpiration ranged from 14.7 to 30.3%depending on different DBH class and was considerably higher in the dry season compared to the wet season.

关键词： heat dissipation method nighttime sap flow nighttime leaf transpiration stem water recharge

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Cigarette Use and Secondhand Smoke Exposure Among Secondary School Students—China,2023

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China CDC weekly 2024年第22期6卷 509-515页

作者： Xinying zeng Shiwei Liu Lin xiao Tobacco Control Office Chinese Center for Disease Control and PreventionBeijingChina

What is already known about this topic?In 2021,the prevalence of experimental and current cigarette use among secondary school students in China stood at 16.7%and 4.7%,***,39.9%of these students were exposed to secondhand smoke at *** is added by this report?In comparison to 2021,the prevalence of current cigarette use remained unchanged at 4.2%in 2023,whereas experimental use declined to 13.7%.Notably,rates were significantly higher among vocational senior high school(VSHS)students relative to their peers in senior high school(SHS)and junior high school(JHS).Furthermore,exposure to secondhand smoke in schools decreased to 35.4%in 2023 from previously recorded levels,with more pronounced reductions observed in JHS and SHS populations and no notable change among VSHS *** are the implications for public health practice?Targeted tobacco control policies are imperative for secondary school students,including the establishment of smoke-free school ***,it is crucial to pay close attention to the needs of VSHS students.

关键词： smoke unchanged senior

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Constructing Built-In Electric Fields with Semiconductor Junctions and Schottky Junctions Based on Mo-MXene/Mo-Metal Sulfides for Electromagnetic Response

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Nano-Micro Letters 2024年第10期16卷 453-473页

作者： xiaojun zeng xiao Jiang Ya Ning Yanfeng Gao Renchao Che School of Materials Science and Engineering Jingdezhen Ceramic UniversityJingdezhen 333403People's Republic of China School of Materials Science and Engineering Shanghai UniversityShanghai 200444People's Republic of China Laboratory of Advanced Materials Shanghai Key Lab of Molecular Catalysis and Innovative MaterialsAcademy for Engineering and TechnologyFudan UniversityShanghai 200438People's Republic of China Zhejiang Laboratory Hangzhou 311100People's Republic of China

The exploration of novel multivariate heterostructures has emerged as a pivotal strategy for developing high-performance electromagnetic wave(EMW)absorption ***,the loss mechanism in traditional heterostructures is relatively simple,guided by empirical observations,and is not *** this work,we presented a novel semiconductor-semiconductor-metal heterostructure sys-tem,Mo-MXene/Mo-metal sulfides(metal=Sn,Fe,Mn,Co,Ni,Zn,and Cu),including semiconductor junctions and Mott-Schottky *** skillfully combining these distinct functional components(Mo-MXene,MoS_(2),metal sulfides),we can engineer a multiple heterogeneous interface with superior absorption capabilities,broad effective absorption bandwidths,and ultrathin matching *** successful establishment of semiconductor-semiconductor-metal heterostructures gives rise to a built-in electric field that intensifies electron transfer,as confirmed by density functional theory,which collaborates with multiple dielectric polarization mechanisms to substantially amplify EMW *** detailed a successful synthesis of a series of Mo-MXene/Mo-metal sulfides featuring both semiconductor-semiconductor and semiconductor-metal *** achievements were most pronounced in Mo-MXene/Mo-Sn sulfide,which achieved remarkable reflection loss values of-70.6 dB at a matching thickness of only 1.885 *** cross-section calculations indicate that these MXene/Mo-metal sulfides have tremendous potential in practical military stealth *** work marks a departure from conventional component design limitations and presents a novel pathway for the creation of advanced MXene-based composites with potent EMW absorption capabilities.

关键词： Semiconductor-semiconductor-metal heterostructure Semiconductor junctions Mott-Schottky junctions Built-in electric field Electromagnetic wave absorption

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Achieving structurally stable O3-type layered oxide cathodes through site-specific cation-anion co-substitution for sodium-ion batteries

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Journal of Energy Chemistry 2024年第6期93卷 411-418,I0011页

作者： Yihao Shen Chen Cheng xiao Xia Lei Wang Xi Zhou pan zeng Jianrong zeng Liang Zhang Institute of Functional Nano&Soft Materials(FUNSOM) Soochow UniversitySuzhou 215123JiangsuChina Institute for Advanced Study School of Mechanical EngineeringChengdu UniversityChengdu 610106SichuanChina Shanghai Synchrotron Radiation Facility Shanghai Advanced Research InstituteChinese Academy of SciencesShanghai 201204China Shanghai Institute of Applied physics Chinese Academy of SciencesShanghai 201800China Jiangsu Key Laboratory of Advanced Negative Carbon Technologies Soochow UniversitySuzhou 215123JiangsuChina

O3-type layered oxides have garnered great attention as cathode materials for sodium-ion batteries because of their abundant reserves and high theoretical ***,challenges persist in the form of uncontrollable phase transitions and intricate Na^(+)diffusion pathways during cycling,resulting in compromised structural stability and reduced capacity over *** study introduces a special approach employing site-specific Ca/F co-substitution within the layered structure of O_(3)-NaNi_(0.5)Mn_(0.5)O_(2) to effectively address these ***,the strategically site-specific doping of Ca into Na sites and F into O sites not only expands the Na^(+)diffusion pathways but also orchestrates a mild phase transition by suppressing the Na^(+)/vacancy ordering and providing strong metal-oxygen bonding strength,*** as-synthesized Na_(0.95)Ca_(0.05)Ni_(0.5)Mn_(0.5)O_(1.95)F_(0.05)(NNMO-CaF)exhibits a mild O3→O3+O'3→p3 phase transition with minimized interlayer distance variation,leading to enhanced structural integrity and stability over extended *** a result,NNMO-CaF delivers a high specific capacity of 119.5 mA h g^(-1)at a current density of 120 mA g^(-1)with a capacity retention of 87.1%after 100 *** study presents a promising strategy to mitigate the challenges posed by multiple phase transitions and augment Na^(+)diffusion kinetics,thus paving the way for high-performance layered cathode materials in sodium-ion batteries.

关键词： Sodium-ion batteries O3-type layered oxides Site-specific co-doping phase transition

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Optically levitated micro gyroscopes with an MHz rotational vaterite rotor

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Microsystems & Nanoengineering 2024年第3期10卷 219-227页

作者： Kai zeng Xiangming Xu Yulie Wu Xuezhong Wu Dingbang xiao College of Intelligence Science and Technology National University of Defense TechnologyChangsha 410073China College of Information and Communication National University of Defense TechnologyWuhan 430000China Key Laboratory of Satellite Navigation Technology National University of Defense TechnologyChangsha 410073China

The field of levitated optomechanics has experienced significant advancements in manipulating the translational and rotational dynamics of optically levitated particles and exploring their sensing *** concept of using optically levitated particles as gyroscopes to measure angular motion has long been explored but has not yet been proven either theoretically or *** this study,we present the first rotor gyroscope based on optically levitated high-speed rotating *** gyroscope is composed of a micrometer-size ellipsoidal vaterite particle that is driven to rotate at MHz frequencies in a vacuum *** an external angular velocity is input,the optical axis deviates from its initial position,resulting in changes in the frequency and amplitude of the rotational *** analyzing these changes,the angular velocity of the input can be accurately detected,making it the smallest rotor gyroscope in the *** angular rate bias instability of the gyroscope is measured to be 0.08°/s and can be further improved to as low as 10^(−9)°/h theoretically by cooling the motion and increasing the angular moment of the levitated *** work opens a new application paradigm for levitated optomechanical systems and may pave the way for the development of quantum rotor gyroscopes.

关键词： particles rotational angular

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Impact wear properties of dissimilar joints between bainitic frogs and pearlite rails

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Journal of Iron and Steel Research International 2024年第1期31卷 275-287页

作者： pin-yong zeng Chun-guang Zuo xiao-yu Zhang Wei Li Tribology Research Institute Southwest Jiaotong UniversityChengdu610031SichuanChina

The impact wear behavior and damage mechanism of dissimilar welded joints between U26Mn frog and U75 V rail before and after normalizing treatment were studied by cyclic impact *** experiment indicated that the impact wear volume of the joints increased with the increasing number of impact *** main wear mechanisms include pitting wear,mild fatigue wear,delamination wear,and fatigue wear,and plastic deformation was the primary impact wear *** them,fatigue wear had the greatest influence on wear volume,while other wear mechanisms had limited *** impact wear resistance of the base material was better than that of the heat-affected *** treatment was beneficial to improving the impact wear resistance of welded joints owing to its effect to promote pearlite recovery,grain refinement,and uniform distribution of *** martensite generated in the rail welded joints aggravated the impact wear damage to the materials,which should be avoided.

关键词： Dissimilar welded joint Impact wear Bainitic steel Damage mechanism Wear rate

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The Trend of Smoking-Related Cognition and Its Association with Smoking Behaviors Among Junior High School Students—China,2013–2021

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China CDC weekly 2024年第22期6卷 503-508页

作者： Wenzhao Liu Xinying zeng Qi Su Lin xiao Shiwei Liu Tobacco Control Office Chinese Center for Disease Control and PreventionBeijingChina

What is already known about this topic?In 2013,31.61%of students perceived quitting smoking as difficult,61.73%considered smoking less attractive,and 73.89%believed that secondhand smoke is definitely harmful to *** is added by this report?The percentage of students who perceived quitting smoking as difficult increased from 31.61%in 2013 to 38.83%in 2021,while the percentage of students who found smoking less attractive rose from 61.73%to 69.40%.Conversely,there was a decrease in the percentage of students who perceived secondhand smoke as harmful,from 73.89%to 68.46%.An increased awareness of the hazards of secondhand smoke was associated with a reduction in smoking *** are the implications for public health practice?It is imperative to enhance health education efforts that aim to raise awareness of the hazards of secondhand smoke.

关键词： smoke attractive Junior

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Multicolor circularly polarized phosphorescence of axially chiral binuclear platinum(Ⅱ) complexes

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Science China Chemistry 2024年第11期67卷 3757-3766页

作者： Jintong Song Rui zeng Hui xiao Hailiang Ni Zong-Xiang Xu Haifeng Xiang College of Chemistry and Materials Science Sichuan Normal University Department of Chemistry Southern University of Science and Technology College of Chemistry Sichuan University

D-A charge transfer, including through-bond charge transfer and through-space charge transfer between two different electron donors（D） and electron acceptors（A）, is a fundamental and powerful tool to tune the optical properties of organic dyes. Herein,we demonstrate a unique strategy to tune phosphorescence and circularly polarized luminescence properties of axially chiral binuclear pt（Ⅱ） complexes through long-range charge transfer, even though these molecules have two totally identical segments on either side of the chiral core. The presence of axial chirality would break not only the symmetry of molecular structure and π-conjugation system but also the symmetry of charge distribution for long-range charge transfer. These binaphthyl-based pt（Ⅱ）complexes bearing coordinated atoms far away from chiral axis exhibit no pt-pt interactions but colorful concentrationdependent phosphorescence with quantum yield up to 86.4% and could be applied as emitters in highly efficient solutionprocessed organic light-emitting diodes to achieve luminance, luminance efficiency, power efficiency, external quantum efficiency, and asymmetry factor up to 8.94 × 10～3cd m-2, 41.9 cd A-1, 18.8 lm W-1, 12.6% and 2.98 × 10-3, respectively. Therefore,the present work affords a new and simple way to utilize the inherently asymmetric advantage of chirality for the design of D-Abased organic dyes.

关键词： pt(II) complexes organic light-emitting diodes circularly polarized phosphorescence axial chirality

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Treg Immunomodulation Contributes to the Anti-atherosclerotic Effects of Huxin Formula in ApoE^(-/-)Mice

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Chinese Journal of Integrative Medicine 2024年第10期30卷 896-905页

作者： OU xiao-min CAI Jing HU xiao-yue zeng Qiao-huang LAN Tao-hua JIANG Wei The Second Clinical College of Guangzhou University of Chinese Medicine Guangzhou510405China Department of Cardiology Guangdong Provincial Hospital of Chinese Medicinethe Second Affiliated Hospital of Guangzhou University of Chinese MedicineGuangzhou510020China Guangdong provincial Key Laboratory of Chinese Medicine for prevention and Treatment of Refractory Chronic Diseases Guangzhou510020China

Objective:To explore the effects of Huxin formula(HXF)in curtailing atherosclerosis and its underlying ***:According to random number table method,24 specific pathogen free male ApoE^(-/-)mice were randomly divided into model group,HXF low-dose(HXF-L)group(8.4 g/kg daily),HXF high-dose(HXF-H)group(16.8 g/kg daily),and pravastatin(8 mg/kg daily)group in ExperimentⅠ(n=6 per group).C57BL/6J mice served as the control group(n=6).ApoE^(-/-)mice in HXF-L,HXF-H,pravastatin groups were fed a Western diet and administered continuously by gavage for 12 weeks,while C57BL/6J mice in the control group were fed conventional lab mouse chow for 12 ***,Tregs were depleted by weekly intraperitoneal injection of purified anti-mouse CD25 antibody(pC61,250μg per mouse)for 4 weeks in ExperimentⅡ(n=6 per group).Oil Red O and Masson staining were used to evaluate the plaque area and aortic root *** CD4^(+)CD25^(+)Foxp3^(+)Treg counts in the lymph nodes and spleen cells were detected using flow cytometric *** transforming growth factor-β1(TGF-β1),interleukin(IL)-10,and IL-6 serum levels were examined by MILLIpLEX?MAp *** real-time reverse transcription pCR(qRT-pCR)and Western blot were utilized to assess the expression of TGF-βmRNA and protein in the *** expression of CD4^(+)T lymphocytes,macrophages and smooth muscle cells in the aortic root were detected by immunofluorescence ***:HXF reduced plaque area in ApoE^(-/-)mice(pph nodes and spleen cells(ppponse via elevating IL-10 and TGF-β1 serum levels(ppoE^(-/-)mice(p>0.05).Also,HXF upregulated the expression of TGF-βmRNA and protein in the aorta(pphocytes,macrophages and smooth muscle cells in aortic root plaque(ppletion of Tregs with CD25

关键词： atherosclerosis Huxin Formula Tregs immune responses inflammation

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prediction of suitable water content in granulation of sintering mixture based on Litster's model

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Journal of Iron and Steel Research International 2024年第3期31卷 552-560页

作者： Fang-lei Dai xiao-hui Fan xiao-xian Huang Xu-ling Chen Min Gan Zhi-yun Ji zeng-qing Sun School of Minerals processing and Bioengineering Central South UniversityChangsha 410083HunanChina

Suitable water content plays a decisive role in the granulation of sintering ***,a method was proposed to predict the suitable water content for effective granulation on the basis of Litster's granulation *** granulation effectiveness of a sintering mixture was predicted by the model,with the allowance error of±10%.The effects of the water absorption properties,particle size composition and content of adhesive particles on the suitable water content were *** results showed that the allowable error of prediction was within±0.5%compared to the experimentally determined suitable water *** an increase in adhesive powder content of mixtures with higher water absorption,the suitable water content increased to achieve similar granulation ***,as the amount of concentrates increased,the suitable water content first increased and then remained *** influence of the water absorption characteristics of the adhesive particles on the suitable water content was less than that of their particle size composition in the mixture.

关键词： Adhesive particle Sintering mixture Granulation effectiveness Suitable water content

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