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temperature is a cryptic factor shaping the geographical pattern of genetic variation in Ceratophyllum demersum across a subtropical freshwater lake

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Plant Diversity 2024年第5期46卷 630-639页

作者： Yixian Li Xuyao Zhao Manli Xia Xinzeng Wei Hongwei Hou The State Key Laboratory of Freshwater Ecology and Biotechnology The Key Laboratory of Aquatic Biodiversity and Conservation of Chinese Academy of SciencesInstitute of HydrobiologyChinese Academy of SciencesWuhan 430072HubeiChina University of Chinese Academy of Sciences Beijing 100049China Key Laboratory of Aquatic Botany and Watershed Ecology Wuhan Botanical GardenChinese Academy of SciencesWuhan 430074HubeiChina

Macrophyte habitats exhibit remarkable heterogeneity,encompassing the spatial variation of abiotic and biotic components such as changes in water conditions and weather as well as anthropogenic *** factors are thought to be important drivers shaping the genetic and epigenetic variation of aquatic ***,the links among genetic diversity,epigenetic variation,and environmental variables remain largely unclear,especially for clonal aquatic ***,we performed population genetic and epigenetic analyses in conjunction with habitat discrimination to elucidate the environmental factors driving intraspecies genetic and epigenetic variation in hornwort(Ceratophyllum demersum)in a subtropical *** factors were highly correlated with the genetic and epigenetic variation of ***,with temperature being a key driver of the genetic *** temperature was detected to be correlated with greater genetic and epigenetic *** and epigenetic variation were positively driven by water temperature,but were negatively affected by ambient air *** findings indicate that the genetic and epigenetic variation of this clonal aquatic herb is not related to the geographic feature but is instead driven by environmental conditions,and demonstrate the effects of temperature on local genetic and epigenetic variation in aquatic systems.

关键词： Genetic diversity Epigenetic variation temperature Macrophyte Restoration

Room-temperature phonon-coupled single-photon emission in hexagonal boron nitride

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Science China(Physics,Mechanics & Astronomy) 2024年第5期67卷 109-114页

作者： Jia-Min Lai Qing-Hai Tan Feilong Song Haonan Chang Yanpei Lv Xue-Lu Liu Jinghua Teng Weibo Gao Ping-Heng Tan Jun Zhang State Key Laboratory of Superlattices and Microstructures Institute of SemiconductorsChinese Academy of SciencesBeijing100083China Key Laboratory of Magnetic Molecules and Magnetic Information Materials of Ministry of Education&Research Institute of Materials Science Shanxi Normal UniversityTaiyuan 030000China Center of Materials Science and Optoelectronics Engineering University of Chinese Academy of SciencesBeijing 100049China Division of Physics and Applied Physics School of Physical and Mathematical SciencesNanyang Technological UniversitySingapore 637371Singapore Institute of Materials Research and Engineering(IMRE) Agency for ScienceTechnology and Research(A*STAR)Singapore 138634Singapore

Photon-lattice(phonon)coupling is fundamental to light-matter interaction,particularly when it reaches the quantum limit of the phonon-coupled single-photon emission,which holds great potential for quantum manipulation and quantum information ***,we report single defect state-phonon coupling in hexagonal boron nitride(h BN)at room *** ultrabroad spectrum of single-photon emissions can be achieved by selecting the excitation *** photoluminescence excitation spectroscopy,we observe single-phonon-assisted resonance-enhanced single-photon emission,along with multiple phonon replicas that herald the creation of phonon Fock *** also develop a transition model to gain insight into the physical process behind the single defect state-phonon *** work sets the stage for manipulating electron-phonon coupling state with single quantum-level precision at room temperature.

关键词： temperature phonon hexagonal

Bose–Einstein distribution temperature features of quasiparticles around magnetopolaron in Gaussian quantum wells of alkali halogen ions

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Chinese Physics B 2024年第9期33卷 521-526页

作者： Xin Zhang Sarengaowa Shuang Han Ran An Xin-Xue Zhang Xin-Ying Ji Hong-Xu Jiang Xin-Jun Ma Pei-Fang Li Yong Sun College of Physics and Electronic Information Inner Mongolia Minzu UniversityTongliao028000China Institute of Condensed Matter Physics Inner Mongolia Minzu UniversityTongliao 028000China

We have applied strong coupling unitary transformation method combined with Bose–Einstein statistical law to investigate magnetopolaron energy level temperature effects in halogen ion crystal quantum *** obtained results showed that under magnetic field effect,magnetopolaron quasiparticle was formed through the interaction of electrons and surrounding *** the same time,magnetopolaron was influenced by phonon temperature statistical law and important energy level shifts down and binding energy *** revealed that lattice temperature and magnetic field could easily affect magnetopolaron and the above results could play key roles in exploring thermoelectric conversion and conductivity of crystal materials.

关键词： temperature effect quantum well asymmetric Gaussian potential magnetopolaron

Effect of temperature on tribofilm growth and the lubrication of the piston ring-cylinder liner system in two-stroke marine engines

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Friction 2024年第8期12卷 1858-1881页

作者： Xiuyi LYU Jiang HU Yunchuan WANG Jinlu SHENG Xuan MA Tongyang LI Chang GE Xiqun LU Chongqing Jiaotong University Chongqing 400074China Chongqing Metropolitan College of Science and Technology Chongqing 402167China Harbin Engineering University Harbin 150001China Yantai Zhongke Research Institute of Advanced Materials and Green Chemical Engineering Yantai 264006China State Key Laboratory of Solid Lubrication Lanzhou Institute of Chemical PhysicsChinese Academy of SciencesLanzhou 730000China

This study is an optimized extension based on the authors’previous research on the tribo-chemical reaction under constant temperature field of two-stroke internal combustion engines(ICEs).It establishes a coupled analysis model that considers the tribo-chemical reactions,dynamic contact,and interface lubrication of the piston ring-cylinder liner(PRCL)system under transient temperature *** this study,for the first time,the prediction of the tribofilm thickness and its influence on the surface micro-topography(the comprehensive roughness)are coupled in the working temperature field of the PRCL system,forming an effective model framework and providing a model basis and analytical basis for subsequent *** study findings reveal that by incorporating temperature and tribofilm into the simulation model,the average friction deviation throughout the stroke decreases from 8.92%to 0.93%when compared to experimental ***,the deviation during the combustion regime reduces from 39.56%to 7.34%.The proposed coupled model provides a valuable tool for the evaluation of lubrication performance of the PRCL system and supports the analysis software forward design in two-stroke ICEs.

关键词： tribofilm piston ring-cylinder liner(PRCL)system temperature comprehensive roughness two-stroke internal combustion engines(ICEs)

Effect of temperature and Grain Boundary on Void Evolution in Irradiated Copper:A Phase-Field Study

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Acta Metallurgica Sinica(English Letters) 2024年第9期37卷 1621-1632页

作者： Qionghuan Zeng Yiming Chen Zhongsheng Yang Yunhao Huang Zhijun Wang Junjie Li Jincheng Wang tate Key Laboratory of Solidification Processing Northwestern Polytechnical UniversityXi’an710072China Science and Technology On Reactor Fuel and Materials Laboratory Nuclear Power Institute of ChinaChengdu610213China

The continued existence of high-energy radiation in nuclear reactors at high temperatures results in the formation of radiation-induced voids,which will further lead to inevitable swellings of polycrystalline structural components and thus premature failures.A deep understanding of the effect of temperature and grain boundary on void evolution in irradiated copper is significant for preventing this kind of ***,the phase-field method was employed to study void evolution in irradiated copper under different temperatures and grain *** results show that,due to the different sensitivities of point defect production rate and vacancy diffusion rate to temperature changes,both the nucleation-growth rate and the coarsening rate during void evolution increase first and then decrease with increasing temperature;moreover,the nucleation mechanism exhibits site-saturated nucleation at low temperatures while continuous nucleation at high *** presence of grain boundary can accelerate the emergence of void because grain boundaries can absorb more interstitials than *** finer the grain size,the stronger inhibitory effect of grain boundaries on the growth rate of void,due to the formation of void denuded zone near grain *** high temperatures,the growth rate of void in fine grains is significantly reduced due to the increase of vacancy diffusion rate and the enhancement of sink effect of grain boundary on vacancy.

关键词： Void evolution Phase-field method temperature Grain boundary

Role of temperature in tribolayers in fretting wear ofγ-TiAl alloy

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Friction 2024年第5期12卷 939-953页

作者： Yulei YANG Hongfei SHANG Huiping PEI Jimin XU Yi LIANG Minghui PAN School of Mechanical Engineering Nanjing University of Science and TechnologyNanjing210094China State Key Laboratory of Tribology in Advanced Equipment Tsinghua UniversityBeijing100084China Institute of Tribology Hefei University of TechnologyHefei230009China

The formation of tribolayers may play significant influences on fretting *** elevated temperature,the adhesion among wear debris and the increased diffusion rate facilitate the formation of ***,the intensification of oxidation at elevated temperature and the low diffusion rate in oxides may play an adverse *** present study aims to investigate the role of temperature in tribolayers in fretting wear using aγ-TiAl *** electron microscope,energy dispersive spectrometer,Raman spectrometer,transmission electron microscope and nanoindentation were utilized to investigate the wear debris,tribolayers,and wear *** fretting tests showed that,compared with that at room temperature(RT)and 350℃,significant reduction in wear rate and decrease in the fluctuation of friction coefficient occurred at 550 and 750℃.It was further revealed that when temperature raised from room temperature(RT)to 750℃,the oxidation of the wear debris increased slightly and the diffusion coefficients increased prominently,which facilities the formation of well tribo-sintered *** well tribo-sintered tribolayers presented homogenous structure,nanocrystalline grains with excellent mechanical properties,and resulted in the improvement in the fretting wear resistance of theγ-TiAl alloy at 550 and 750℃.

关键词： tribolayer temperature fretting wear γ-TiAl alloy

Adhesion Performances Between Two Orthotropic Solids Influenced by temperature Increment

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Acta Mechanica Solida Sinica 2024年第3期37卷 430-443页

作者： Qing-Hui Luo Yue-Ting Zhou School of Aerospace Engineering and Applied Mechanics Tongji UniversityShanghai200092China

The classical adhesive contact models belong to isothermal adhesion theories,where the effect of temperature on adhesion was ***,a number of experimental results indicated that the adhesion behaviors can be significantly affected by *** this paper,the two-dimensional non-slipping anisothermal adhesion behaviors between two orthotropic elastic cylinders are investigated within the framework of the Johnson-Kendall-Roberts *** stated problem is reduced to the coupled singular integral equations by virtue of the Fourier integral transform,which are solved analytically with the analytical function *** closed-form solutions for the stress fields in the presence of thermoelastic effect are *** stable equilibrium state of contact system is determined by virtue of the Griffith energy *** effect of temperature difference on adhesion behaviors between orthotropic solids is *** is found that the difference between the oscillatory and non-oscillatory solutions increases with increasing the degree of anisotropy of orthotropic *** oscillatory solution cannot be well approximated by the non-oscillatory solution for the orthotropic materials with relatively high anisotropy.

关键词： Adhesive contact Non-slipping JKR model temperature Griffith energy balance

Combined Effect of temperature and Cadmium on Molecular Responses of Hsp70 and P-gp Genes in Crassostrea gigas

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Journal of Ocean University of China 2024年第4期23卷 1115-1120页

作者： HU Fanguang SUN Ming LIU Guangbin JING Yuanyuan CHEN Qun ZHANG Tianwen Marine Science Research Institute of Shandong Province Qingdao 266104China

To evaluate the combined effect of temperature and cadmium on the molecular responses of heat shock protein 70(hsp70)and P-glycoprotein(P-gp)in mantle,digestive gland and gills of Crassostrea gigas,oysters were exposed to combinations of five temperature levels(10,15,20,25,and 30℃)and 10μg L^(-1)cadmium for 21 *** were sampled for mRNA quantification by qPCR,and the results showed that the P-gp gene expression changed significantly after treatment at different temperatures and different treatment *** P-gp gene expression was the highest in the digestive *** with the control group,the P-gp gene expression in cadmium treatment groups at all the different temperatures were significantly higher than the control *** control oysters(kept at 10℃during the whole experiment without cadmium)expressed low levels of hsp70,but the groups treated with cadmium displayed somewhat higher *** present study demonstrated hsp70 and P-gp played an important role in the detoxification of Cd in ***,and confirmed temperature should be considered for the assessment of Cd-induced toxicity in oysters.

关键词： temperature cadmium P-gp hsp70 Crassostrea gigas

Study on the mechanism and law of temperature,humidity and moisture content on the mechanical properties of molded fiber products

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Journal of Bioresources and Bioproducts 2024年第3期9卷 351-368页

作者： Zhiqiang Fu Tong Zhao Hu Wang Jingyi Wei Haozhe Liu Liying Duan Yan Wang Ruixiang Yan School of Light Industry Science and Engineering Tianjin University of Science and TechnologyTianjin 300457China Department of Transportation and Vehicle Engineering Tangshan UniversityTangshan 063000HebeiChina College of Mechanical Engineering Tianjin University of Science and TechnologyTianjin 300457China

The change of temperature, humidity and moisture content (MC) will lead to the change of mechanical properties of molded fiber products (MFP). However, it is difficult to decouple the effects of temperature, humidity and MC on the mechanical properties of MFP, and predict the mechanical properties of MFP during the use. In this study, the laws and mechanism of mechanical properties of MFP with ambient temperature, humidity and MC were studied. The results showed that the direct effect of temperature (20−70 °C) on mechanical properties of MFP was insignificant, and the mechanical properties of MFP were mainly changed by MC. The MC was related to ambient temperature and humidity, and the relationship between the three could be described by the modified Guggenheim-Anderson-de Boer (GAB) model (20−70 °C and 30 %–90 % relative humidity). With the increase of MC, the elastic modulus and fracture strain was increased and decreased linearly, the yield strength and failure strength were presented GaussAmp laws, and the failure strain was presented asymptotic regressed distribution law. Two fracture modes of MFP, brittle fracture and ductile fracture, were revealed by the scanning electron microscopy of the mesoscopic fiber structure of sugarcane bagasse molded fiber products. The mathematical models and the changes of fiber structure were verified by wheat straw molded fiber products and waste paper molded fiber products. This study was contributed to understand the effects and mechanism of the change of temperature, humidity and MC on the mechanical properties of MFP.

关键词： temperature Relative humidity Moisture content Molded fiber products Mechanical properties