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Acta Mechanica Solida Sinica 2014年第4期27卷 373-382页

作者： Quanwei Zhan Tao Suo Cunxian Wang Kui Xie Zhongbin Tang Institute of UAV research Northwestern Polytechnical University School of Aeronautics Northwestern Polytechnical University Department of Mechanical Engineering The Johns Hopkins University 3400 N. Charles StreetBaltimore MD 21218 USA China Electronics Technology Group Corporation No.38 Research Institute

In the present work, we explore the strain hardening behaviors as well as the effect of temperature on the plastic deformation of ultrafine grained aluminum. The temperature sensitivity is determined and compared with that of coarse grained material. The results indicate that the flow stress of ultrafine grained aluminum displays enhanced sensitivity to temperature. The reduction in activation volume is suggested to be the major reason for the enhanced temperature sensitivity as grain size is refined into the sub-micrometer regime. Finally, a phenomenological constitutive model is proposed to describe the post-yield response of ultrafine grained aluminum.

关键词： ultrafine grained aluminum compressive behavior temperature sensitivity strain hardening behavior constitutive relation

Effect of Polymer Matrix on temperature sensitivity of temperature Sensitive Paints

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Chinese Journal of Polymer Science 2015年第10期33卷 1351-1358页

作者： Zhi-dong Wang Xiao-zhong Qu 金毕青 Yi Shi 刘治田金熹高 School of Material Science and Engineering Wuhan Institute of Technology State Key Laboratory of Polymer Physics and Chemistry Institute of Chemistry Chinese Academy of Sciences University of Chinese Academy of Sciences

The thermal quenching behaviors of the temperature sensitivity paints （TSP） composed of europium（III） thenoyltrifluoroacetonate （EuTTA） and Eu-phenanthrene complex （Eu-2） in polystyrene （PS）, polymethylmethacrylate （PMMA） and epoxy resin （EP） were investigated. It is found that both the emission intensity and temperature sensitivity were not only affected by the luminescence probes, but also by the polymer matrix. The interaction between probes and matrix results in the alteration of both the non-radiation decay rate and the activation energy of the non-radiative process for the thermal quenching process, i.e. larger activation energy of the non-radiative process shows higher temperature sensitivity and less emission intensity. Therefore, it was confirmed that the temperature sensitivity and luminescent intensity of TSP depended not only on the luminescence probes but also on the polymer matrix.

关键词： temperature sensitive paints Europium complex Thermal quenching Polymer matrix temperature sensitivity

Nucleoprotein phosphorylation site(Y385)mutation confers temperature sensitivity to influenza A virus due to impaired nucleoprotein oligomerization at a lower temperature

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Science China(Life Sciences) 2021年第4期64卷 633-643页

作者： Weinan Zheng Liang Cui Minghui Li Yun Li Wenhui Fan Limin Yang Jing Li Lei Sun Wenjun Liu CAS Key Laboralory of Pathogenic Microbiology and Immumology Institute of MicrobiologyChinese Academy of SciencesBejing 100101China University of Chinese Academy of Sciences Bejing 100101China State Key Laboratory for Conservation and Urilization of Subtropical Agro-Bioresourses&Laboratory of Animal Infectious Diseases College of Animal Sciences and Veterinary MedicineGuangxi UniversitNanning 530004China Instinute of Microbiology Center for Biosafety Mega-ScienceChinese Academy of SciencesBeijing 100101China

Mutations in viral proteins can lead to the cold adaption of influenza A virus and the cold-adapted virus is an important vaccination ***,we identify a novel strain of influenza A virus with cold sensitivity conferred by a mutation at a phosphorylation site within the nucleoprotein(NP).The highly conserved tyrosine 385 residue(Y385)of NP was identified as a phosphorylation site by mass *** constructive NP phosphorylation mimicked by Y385 E mutation was fatal for virus replication,while the continuous Y385 dephosphorylation mimicked by Y385 F mutation had little impact on virus replication in ***,the Y385 F virus showed much lower replicative capacity in turbinates of mice compared with the wild type ***,the replication of Y385 F virus was significantly reduced in both A549 and MDCK cells grown at 33℃,when compared to that at 37℃.These results indicated that the Y385 F mutation led to cold sensitivity of *** further found that the cold sensitivity of Y385 F virus could be attributed to diminished NP oligomerization rather than any changes in intracellular *** together,these findings suggest that the phosphorylation of NP may be a critical factor that regulates the temperature sensitivity of influenza A virus.

关键词： influenza A virus nucleoprotein phosphorylation dephosphorylation temperature sensitivity

Comparing the temperature sensitivity of organic matter decomposition in oxic and oxygen-deprived soils

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Soil Ecology Letters 2024年第1期6卷 29-32页

作者： Zhenhui Jiang Xin Wang Ting Liu Xiaojuan Feng State Key Laboratory of Vegetation and Environmental Change Institute of BotanyChinese Academy of SciencesBeiing 100093China University of Chinese Academy of Sciences Bejing 100049China State Key Laboratory of Subtropical Silviculture Zhejiang A&F UniversityHangzhou 311300China Henan Key Laboratory of Ecological Environment Protection and Restoration of Yellow River Basin Yellow River Institute of Hydraulic ResearchZhengzhou 450003China

No consistent variation was found in soil respiration Q10 under various O2 *** C quality had a strong effect on Q10 in oxic soils.N limitation had a large impact on Q10 in soils under O2 *** studies on the temperature sensitivity(Q10)of soil organic matter(SOM)decomposition mainly focus on aerobic ***,varia-tions and determinants of Q10 in oxygen(O2)-deprived soils remain *** we incubated three grassland soils under oxic,suboxic,and anoxic conditions subjected to varying temperatures to compare variations in Q10 in relation to changing *** consistent variation was found in Q10 under various O2 *** analysis of edaphic properties demon-strated that substrate carbon quality showed a strong influence on Q10 in oxic soils,whereas nitrogen limitation played a more important role in suboxic and anoxic *** results suggest that substrate carbon quality and nitrogen limitation may play roles of varying importance in determining the temperature sensitivity of SOM decomposition under various O2 conditions.

关键词： oxygen-limited conditions temperature sensitivity soil respiration carbon substrate nitrogen limitation

Thermal sensitivity of photonic crystal fibers in opto-electronic oscillators

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The Journal of China Universities of Posts and Telecommunications 2009年第4期16卷 1-6页

作者： Afshin S. Daryoush Deptartment of ECE Drexel University

Stable opto-electronic oscillators （OEOs） are realized using long fiber delay lines and changes in the index of refraction of high quality factor delay line results in temperature sensitivity of OEOs. temperature sensitivity of various OEOs is measured to compare index of refraction variation of standard （SMF-28） and photonic crystal fiber （PCF）. Both hollow-core （HC） and solid-core （SC） versions of PCF are quantified. SC-PCF exhibited a factor of three reductions in the rate of index of refraction change （about ＋4.7 ppm/℃） with temperature over SMF-28 （about 12 ppm/℃） based OEO. Although HC-PCF have a greater attenuation per unit length, but those fibers have demonstrated a negative rate of change （about - 0.6 ppm/℃） in the effective index of refraction with temperature and prospect of thermal stability in the OEO using passive techniques is great when a combination of HC-PCF and SMF-28 are employed as fiber delay lines.

关键词： opto-electronie oscillators frequency stability phase noise temperature sensitivity photonic crystal fiber hollow and solid core PCF

The effects of climate warming on microbe-mediated mechanisms of sediment carbon emission

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Journal of Environmental Sciences 2023年第7期129卷 16-29页

作者： Weiwei Lü Haoyu Ren Wanchang Ding He Li Xin Yao Xia Jiang College of Water Sciences Beijing Normal UniversityBeijing 100875China State Key Laboratory of Environmental Criteria and Risk Assessment National Engineering Laboratory of Lake Water Pollution Control and Ecological Restoration TechnologyChinese Research Academy of Environmental SciencesBeijing 100012China School of Environment and Planning University of LiaochengLiaocheng 252000China

Due to significant differences in biotic and abiotic properties of soils compared to those of sediments,the predicted underlying microbe-mediated mechanisms of soil carbon emissions in response to warming may not be applicable for estimating similar emissions from inlandwater *** addressed this issue by incubating different types of sediments,(including lake,small river,and pond sediments)collected from 36 sites across the Yangtze River basin,under short-term experimentalwarming to explore the effects of climatewarming on sediment carbon emission and the underlying microbe-mediated *** results indicated that under climate warming Cc emissions were affected more than CH_(4) emissions,and that pond sediments may yield a greater relative contribution of CO_(2) to total carbon emissions than lake and river ***-induced CO_(2) and CH_(4) increases involve different microbe-mediated mechanisms;Warming-induced sediment CO_(2) emissions were predicted to be directly positively driven by microbial community network modularity,which was significantly negatively affected by the quality and quantity of organic carbon and warming-induced variations in dissolved oxygen,Conversely,warminginduced sediment CH_(4) emissionswere predicted to be directly positively driven bymicrobial community network complexity,which was significantly negatively affected by warminginduced variations in *** findings suggest that biotic and abiotic drivers for sediment CO_(2) and CH_(4) emissions in response to climate warming should be considered separately when predicting sediment organic carbon decomposition dynamics resulting from climate change.

关键词： Inland water sediments temperature sensitivity Carbon emission Microbe-mediated mechanism Short-term experimental warming

Compact temperature-insensitive modulator based on a silicon microring assistant Mach-Zehnder interferometer

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Chinese Physics B 2012年第12期21卷 250-257页

作者：张雪键冯雪张登科黄翊东 State Key Laboratory of Integrated Optoelectronics Department of Electronic EngineeringTsinghua University

On the silicon-on-insulator platform, an ultra compact temperature-insensitive modulator based on a cascaded microring assistant Mach-Zehnder interferometer is proposed and demonstrated with numerical simulation. According to the calculated results, the tolerated variation of ambient temperature can be as high as 134 ℃ while the footprint of such a silicon modulator is only 340 μm2.

关键词： integrated modulator temperature sensitivity microring Mach-Zehnder interferometer

Experimental study on the influence of temperature cycle on low-rank coal permeability

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Science China(Technological Sciences) 2020年第6期63卷 1055-1065页

作者： ZOU JunPeng JIAO YuYong RATHNAWEERA T D WANG Hao Faculty of Engineering China University of GeosciencesWuhan 430074China Department of Civil Engineering Monash UniversityMelbourne VIC 3800Australia State Key Laboratory of Geomechanics and Geotechnical Engineering Institute of Rock and Soil MechanicsChinese Academy of SciencesWuhan 430071China

The formation temperature is a key factor affecting coalbed methane(CBM)migration in *** the prediction of CBM production and prevention of mine gas disasters require the understanding on the controlling mechanism of temperature on coal *** experimentally examined the evolution of permeability for natural low-rank coal samples under various stresses and cyclic temperature *** permeability and intrinsic permeability decrease significantly when the temperature increases and they only partially recover after the temperature *** permeability loss decreases greatly with the increasing number of temperature *** permeability loss due to the rising temperature and the irreversible permeability loss for a whole temperature cycle decrease prominently with increasing confining *** impacts of swelling/shrinking of coal matrix,roughness of surface,pore compressibility and weakly bound water in coal on temperature sensitivity of coal permeability are investigated.

关键词： low-rank coal permeability temperature cycle temperature sensitivity

Long-term thinning decreases the contribution of heterotrophic respiration to soil respiration in subalpine plantations

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Journal of Forestry Research 2024年第3期35卷 189-204页

作者： Longfei Chen Zhibin He Wenzhi Zhao Xi Zhu Qin Shen Mingdan Song Zhengpeng Li Junqia Kong Shuping Yang Yuan Gao Northwest Institute of Eco-Environment and Resources Chinese Academy of SciencesLanzhou 730000People's Republic of China State Forestry Administration Key Laboratory of Forest Resources and Environmental Management Beijing Forestry UniversityBeijing 100083People's Republic of China Academy of Agriculture and Forestry Sciences Qinghai UniversityXining 810000People's Republic of China College of Landscape Architecture Zhejiang A&F UniversityHangzhou 310000People's Republic of China

Interest in the dynamics of soil respiration(R_(S))in subalpine forest ecosystems is increasing due to their high soil carbon density and potential sensitivity to environmental ***,as a principal silvicultural practice,the long-term impacts of thinning on R_(S) and its heterotrophic and autotrophic respiration components(R_(h) and Ra,respectively)in subalpine plantations are poorly understood,espe-cially in winter.A 3-year field observation was carried out with consideration of winter CO_(2) efflux in middle-aged sub-alpine spruce plantations in northwestern China.A trench-ing method was used to explore the long-term impacts of thinning on Rs,Rn and R_(a).Seventeen years after thinning,mean annual Rs,Rn and R_(a) increased,while the contribu-tion of R_(h) to R_(s) decreased with thinning *** significantly decreased winter R,because of the reduction in R_(n) but had no significant effect on *** temperature sensitivity(Q_(10))of R_(h) and R_(a) also increased with thinning intensity,with lower Q_(10) values for R_(h)(2.1-2.6)than for Ra(2.4-2.8).The results revealed the explanatory variables and pathways related to R_(n) and R_(a) *** increased soil moisture and nitrate nitrogen(NO_(3)^(-)-N),and the enhanced nitrogen and water availability promoted R_(h) and R_(a) by improving fine root biomass and microbial *** results highlight the positive roles of NO_(3)^(-)-N in stimulating R_(s) components following long-term ***,applications of nitrogen fertilizer are not recommended while thinning subalpine spruce plantations from the perspective of reducing soil CO_(2) *** increased Q_(10) values of R_(s) components indicate that a large increase in soil CO_(2) emissions would be expected following thinning because of more pronounced climate warming in alpineregions.

关键词： Heterotrophic respiration Autotrophic respiration Long-term thinning impacts Cold seasons Subalpine plantations temperature sensitivity

Soil temperature and moisture sensitivities of soil CO_2 efflux before and after tillage in a wheat field of Loess Plateau,China

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Journal of Environmental Sciences 2011年第1期23卷 79-86页

作者： Hongxing Zhang Xiaoke Wang Zongwei Feng Junzhu Pang Fei Lu Zhiyun Ouyang Hua Zheng Wenzhao Liu Dafeng Hui State Key Laboratory of Urban and Regional Ecology Research Center for Eco-Environmental Sciences Chinese Academy of Sciences Beijing 100085 China Institute of Soil and Water Conservation Chinese Academy of Sciences and Ministry of Water Resources Shaanxi 722400 China Department of Biological Sciences Tennessee State University 3500 John A. Merritt Blvd. Nashville TN 37209 USA

As a conventional farming practice, tillage has lasted for thousands of years in Loess Plateau, China. Although recent studies show that tillage is a prominent culprit to soil carbon loss in croplands, few studies have investigated the influences of tillage on the responses of soil CO2 efflux （SCE） to soil temperature and moisture. Using a multi-channel automated CO2 efflux chamber system, we measured SCE in situ continuously before and after the conventional tillage in a rain fed wheat field of Loess Plateau, China. The changes in soil temperature and moisture sensitivities of SCE, denoted by the Q10 value and linear regression slope respectively, were compared in the same range of soil temperature and moisture before and after the tillage. The results showed that, after the tillage, SCE increased by 1.2-2.2 times; the soil temperature sensitivity increased by 36.1%-37.5%; and the soil moisture sensitivity increased by 140%-166%. Thus, the tillage-induced increase in SCE might partially be attributed to the increases in temperature and moisture sensitivity of SCE.

关键词： soil CO2 efflux Loess Plateau moisture sensitivity temperature sensitivity tillage wheat field