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[CO_2]和温度增加的相互作用对植物生长的影响 被引量:15
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作者 杨金艳 杨万勤 王开运 《应用与环境生物学报》 CAS CSCD 2002年第3期319-324,共6页
The global environment is changing with increasing temperature and atmospheric carbon dioxide concentration. Because the two factors are concomitant and the rise of global carbon dioxide concentration will affect all ... The global environment is changing with increasing temperature and atmospheric carbon dioxide concentration. Because the two factors are concomitant and the rise of global carbon dioxide concentration will affect all biomass across the full global range of temperatures, we review the theory regarding and observations on the effects of temperature and carbon dioxide concentration interactions onplant carbon balance, growth, development, biomass accumulation and yield. Although there are sound theoretical reasons for expecting a large stimulation of net CO 2 assimilation rates by increased \[CO 2 \] at higher temperatures, this does not necessarily mean that the pattern of biomass and yield responses to increasing \[CO 2 \] and temperature are determined by this response. This paper reviews the interactions between the effects of \[CO 2 \] and different temperatures on plants. There is little unequivocal evidence for large differences in response to \[CO 2 \] at different temperatures, as studies are confounded by the different responses of the species adapted and acclimated to different temperatures, and the interspecific difference in growth form and development pattern. It is coueluded that stress we should the importance of initiation and expansion of meristems and organs and the balance between assimilate supply and sink activity in determining the growth response to increasing \[CO 2 \] and temperature. Tab 1 , Ref 展开更多
关键词 [CO2] 温度增加 相互作用 植物 生长
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开顶式气室原位模拟温度和CO_2浓度升高在早稻上的应用效果 被引量:21
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作者 万运帆 游松财 +4 位作者 李玉娥 王斌 高清竹 秦晓波 刘硕 《农业工程学报》 EI CAS CSCD 北大核心 2014年第5期123-130,共8页
该研究针对气候变化模拟中自由大气CO2浓度增加和红外增温技术投入及运行成本高、波动大,而全封闭的环境模拟室对作物生长环境改变大的不利因素,对传统的开顶式气室(open-top chamber,OTC)系统加以改进,采用将 OTC 外部空气抽入... 该研究针对气候变化模拟中自由大气CO2浓度增加和红外增温技术投入及运行成本高、波动大,而全封闭的环境模拟室对作物生长环境改变大的不利因素,对传统的开顶式气室(open-top chamber,OTC)系统加以改进,采用将 OTC 外部空气抽入内部交换过程中自动控制增补 CO2浓度及加热增温的方式来模拟未来大气中 CO2浓度及气温升高的情况,在早稻生育期内对其温度、CO2浓度和空气相对湿度进行了监测,结果表明:可控温及CO2的 OTC 内部的日平均温度控制偏差能达到&#177;0.2℃以内,最大偏差为-0.58℃;对 CO2浓度的控制偏差范围在-39.4~4.8μL/L,达到了很好的控制效果,完全可以用于气候变化研究中模拟大气CO2浓度及温度升高的情景。同时,该研究还对OTC内部的空气湿度进行了监测,其结果显示在不增温的情况下对空气相对湿度无影响,若增温,则OTC内部的空气相对湿度会增加2%左右。总体来说,可控温及CO2的OTC技术可以用于稻田气候变化模拟试验研究。 展开更多
关键词 气候变化 二氧化碳 温度 开顶式气室 温度增加 CO2浓度升高 原位模拟
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电动助力转向系统无刷电机温度研究
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作者 陈金 钱伟康 《电子科技》 2015年第10期169-172,共4页
电动助力转向系统由控制器ECU根据传感器手力矩、车速等信息确定电机助力,电机与ECU热管理是其成本控制与系统安全的关键。文中提出在控制中区分快速与慢速发热模型,得到了系统温度的增加值,在不同发热均恒条件下与当前温度、输入电流... 电动助力转向系统由控制器ECU根据传感器手力矩、车速等信息确定电机助力,电机与ECU热管理是其成本控制与系统安全的关键。文中提出在控制中区分快速与慢速发热模型,得到了系统温度的增加值,在不同发热均恒条件下与当前温度、输入电流的关系,估算电机温度。仿真与实验证明,通过这种热管理分析与设计方法有效地解决了系统发热问题,成功地实现了系统成本与系统安全的统一。 展开更多
关键词 电动助力转向系统 温度估算 热保护 温度增加
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近地磁尾方位角流能量转换过程
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作者 朱光振 马玉端 +3 位作者 魏新华 杨旭 王健强 王卫 《地球物理学报》 SCIE EI CAS CSCD 北大核心 2023年第2期472-484,共13页
高速流是磁尾等离子体片中质量、能量和磁通量最重要的输运形式.高速流在地向运动到近地磁尾后流速会降低,主导方向也经常转为晨昏方向.在等离子体流速及其主导分量、密度和温度等宏观参数变化的过程中,可能伴随有不同类型的能量转换.为... 高速流是磁尾等离子体片中质量、能量和磁通量最重要的输运形式.高速流在地向运动到近地磁尾后流速会降低,主导方向也经常转为晨昏方向.在等离子体流速及其主导分量、密度和温度等宏观参数变化的过程中,可能伴随有不同类型的能量转换.为此,我们分析近地磁尾方位角流事件期间的能量转换过程.基于整体流速的主导分量为晨昏向,及事件期间的平均温度比其前后增强的选取原则,从2008-2020年期间THEMIS中的三颗卫星(THA,THD,THE)运行在磁尾时的观测数据中,共筛选出821个平均温度比其前/后(事件之前或事件之后10 min)升高的方位角流事件.2011年5月16日的方位角流事例研究发现:能量超过1 keV尤其是超过10 keV的高能离子通量增加,可导致低速低温等离子体的密度、温度和流速增加;磁场减小及磁场功率谱密度的分析表明等离子体和磁能的转换发生在频率为0.01~0.334 Hz的低频波动,仅1%能量耗散.统计给出方位角流事件的平均温度约为3.7 keV,比其前后增加的幅度大部分集中在100~1000 eV.事件期间的平均数密度可能升高或者降低,二者概率大致相当.约96%的平均温度和密度同时大于其前后的方位角流事件,当地等离子体通量管熵也皆大于事件的前后值;电磁能流密度增大,34%的事件期间电磁能流密度主要沿着背景磁力线方向,可影响电离层内方位角方向上的极光膨胀过程.我们的研究结果表明温度和密度同时增加的方位角流事件等离子体宏观参数变化可能暗含磁层-电离层能量耦合过程,有助于理解极光椭圆带赤道向边界的局部增亮现象和磁尾等离子体片中的磁通量. 展开更多
关键词 方位角流 能量转换 温度增加 低频
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红松和蒙古栎种子萌发及幼苗生长对升温与降水综合作用的响应 被引量:12
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作者 赵娟 宋媛 +6 位作者 孙涛 毛子军 刘传照 刘林馨 刘瑞鹏 侯玲玲 李兴欢 《生态学报》 CAS CSCD 北大核心 2012年第24期7791-7800,共10页
研究气候变暖导致的温度升高和降水格局的变化对典型植被类型建群种植物种子萌发和幼苗存活的影响,对于预测森林群落的发展趋势、种质资源保育及森林抚育更新具有重要意义。以寒温带针阔混交林的建群种和优势种红松Pinus koraiensis、... 研究气候变暖导致的温度升高和降水格局的变化对典型植被类型建群种植物种子萌发和幼苗存活的影响,对于预测森林群落的发展趋势、种质资源保育及森林抚育更新具有重要意义。以寒温带针阔混交林的建群种和优势种红松Pinus koraiensis、蒙古栎Quercus mongolica种子和幼苗为研究对象,采用空间替代法模拟温度升高和降水变化,观察其种子萌发和幼苗生长情况。结果表明:与种源地相比,蒙古栎种子在温度升高与降水增加(年均温+4.9℃,+330 mm)或降水减少(年均温+2.8℃,-249 mm)的条件下萌发率分别下降了13%和18%,但差异不显著。红松种子在温度升高与降水增加的情况下萌发率比种源地提高了2.29倍,而降水减少时则下降了64%,不同的地点对红松的萌发率差异极显著;不同的温度、降水组合对红松和蒙古栎幼苗的生长均产生不同影响,在温度升高与降水增加与降水减少的情况下,1年生蒙古栎幼苗的株高、基径和主根长度均有明显下降,与种源地差异显著,而对红松幼苗生长的影响差异不显著;温度升高和降水增加或降水减少的交互作用使蒙古栎幼苗和红松幼苗总生物量下降,尤其是在温度升高与降水增加的条件下两种幼苗的生物量最小,分别比种源地下降了62%和20%。但统计分析表明,红松幼苗生物量在3个样地间没有显著差异。温度升高和降水变化均降低了两种幼苗的根冠比,而比叶面积没有显著差异。 展开更多
关键词 气候变化 温度增加 降水格局 生物量 根冠比 比叶面积
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水分减少与增温处理对冬小麦生物量和土壤呼吸的影响 被引量:1
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作者 毛明翠 刘畅 +2 位作者 曹静 刘宝康 张志东 《环境与发展》 2019年第2期15-16,共2页
利用田地进行控制实验,将实验田平均分成四份,其中三份处理方式如下:减少30%的水分、升高温度(2℃)、减少30%的水分并升温2℃,剩下的一份作为对照田处理。采用特定方法测定土壤呼吸,观察分析减少水分与增加温度对冬小麦的生物量与土壤... 利用田地进行控制实验,将实验田平均分成四份,其中三份处理方式如下:减少30%的水分、升高温度(2℃)、减少30%的水分并升温2℃,剩下的一份作为对照田处理。采用特定方法测定土壤呼吸,观察分析减少水分与增加温度对冬小麦的生物量与土壤呼吸有何影响。 展开更多
关键词 水分减少 增加温度 冬小麦
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增温对蒿类荒漠草地可萌发土壤种子库及其多样性的影响 被引量:8
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作者 田梦 孙宗玖 +1 位作者 李培英 汪洋 《草地学报》 CAS CSCD 北大核心 2020年第1期141-148,共8页
为探讨草地土壤种子库种子萌发对全球气候变暖的适应机制,本研究采用常规方法对模拟温度增加[对照(CK)、增加2℃(T2)、增加4℃(T4)、增加6℃(T6)]下中度退化蒿类荒漠草地可萌发土壤种子库数量及其多样性进行了观测。结果表明:0~5,5~10 c... 为探讨草地土壤种子库种子萌发对全球气候变暖的适应机制,本研究采用常规方法对模拟温度增加[对照(CK)、增加2℃(T2)、增加4℃(T4)、增加6℃(T6)]下中度退化蒿类荒漠草地可萌发土壤种子库数量及其多样性进行了观测。结果表明:0~5,5~10 cm土层土壤种子库萌发的物种数及其幼苗总密度随温度增加呈下降趋势,且T6处理0~5(5~10)cm萌发物种数及萌发密度依次较对照降低57.1%(33.3%),70.4%(75.0%)。随温度增加,0~5,5~10 cm土层蒿类荒漠可萌发土壤种子库物种组成与地上植被物种组成相似性总体呈下降趋势,且T6处理相似性最低。温度增加后蒿类荒漠土壤萌发物种的Shannon-Wiener指数、Pielou指数、Patrick指数总体呈下降趋势,且0~5 cm土层较5~10 cm土层下降明显。综上,增温抑制了土壤种子库种子的萌发,可能不利于退化蒿类荒漠草地的恢复。 展开更多
关键词 温度增加 蒿类荒漠草地 土壤种子库 植物多样性 群落相似性
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内蒙古西中东部代表站近50年气温变化特征对比分析 被引量:1
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作者 张金硕 包福祥 +2 位作者 石力伟 张国栋 王耀廷 《内蒙古林业科技》 2013年第1期37-39,共3页
选取代表内蒙古西、中、东部的阿拉善左旗、呼和浩特、海拉尔3个站1961-2010年气温资料,用线性回归、方差分析、对比分析等统计方法分析年平均气温、年平均最高气温、年平均最低气温的年代际变化特征以及季节性变化规律,总结代表站温度... 选取代表内蒙古西、中、东部的阿拉善左旗、呼和浩特、海拉尔3个站1961-2010年气温资料,用线性回归、方差分析、对比分析等统计方法分析年平均气温、年平均最高气温、年平均最低气温的年代际变化特征以及季节性变化规律,总结代表站温度变化的异同点,并得出近50年来各代表站的平均气温均以每10年0.57℃的幅度增加的结论。 展开更多
关键词 气温 变化特征 温度增加 对比分析
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航空发动机叶片气膜孔主要加工方法的研究
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作者 王宁 《中国科技期刊数据库 工业A》 2016年第9期73-73,共1页
本文主要介绍了航空发动机的叶片气膜孔加工的特点,以及我们常用的方法。系统阐释了纳秒激光加工和电火花加工的过程中,为什么会产生再铸层和微裂纹,以及再产生的新物质对叶片疲劳带来的危害。此外,还对秒激光以及加工特性进行了系统阐... 本文主要介绍了航空发动机的叶片气膜孔加工的特点,以及我们常用的方法。系统阐释了纳秒激光加工和电火花加工的过程中,为什么会产生再铸层和微裂纹,以及再产生的新物质对叶片疲劳带来的危害。此外,还对秒激光以及加工特性进行了系统阐释,与飞秒激光加工、性等轴晶材料、定向高温合金、单晶高温合金进行了对比,并且分析其原因。指出加工航空发动机叶片气膜孔的办法是,研究飞秒激光对定向高温合金、单晶高温合金的损伤机理。 展开更多
关键词 叶片气膜孔 纳秒激光加工 电火花加工 电液束加工 飞秒激光加工我们一般提高燃烧室温度的来增加发动机效
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Degradation of aniline by Fe^(2+)-activated persulfate oxidation at ambient temperature 被引量:12
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作者 张永清 谢晓芳 +1 位作者 黄伟林 黄少斌 《Journal of Central South University》 SCIE EI CAS 2013年第4期1010-1014,共5页
The aniline degradation by persulfate activated with ferrous ion (Fe2+ ) was investigated in batch reactor at ambient temperature. The experimental factors in aqueous solutions including persulfate concentration, Fe2+... The aniline degradation by persulfate activated with ferrous ion (Fe2+ ) was investigated in batch reactor at ambient temperature. The experimental factors in aqueous solutions including persulfate concentration, Fe2+ concentration, pH and ionic strength level were discussed. It is demonstrated that, aniline degradation rate increases with increasing persulfate concentration, but much more ferrous ion inhibits the aniline degradation. When the aniline concentration is 0.10 mmol/L, the maximum aniline degradation occurs at the S2O82- to Fe2+ molar ratio of 250/5 at pH 7.0. In the pH range of 5.0-8.5, increasing pH causes higher aniline degradation. What's more, the increase of ionic strength in solution causes inhibiting in the reaction. Produced intermediates during the oxidation process were identified using gas chromatography-mass spectrometry (GC-MS) technology. And degradation pathways of aniline were also tentatively proposed. 展开更多
关键词 ANILINE ferrous ion PERSULFATE DEGRADATION
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Microwave absorbing characteristics and temperature increasing behavior of basic cobalt carbonate in microwave field
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作者 刘秉国 彭金辉 +4 位作者 张利波 SRINIVASAKANNAN C 黄铭 张泽彪 郭胜惠 《Journal of Central South University》 SCIE EI CAS 2010年第6期1211-1215,共5页
The microwave absorbing characteristics of basic cobalt carbonate,cobalt oxide(Co3O4),and the mixture of basic cobalt carbonate and cobalt oxide were investigated by means of microwave cavity perturbation,their temper... The microwave absorbing characteristics of basic cobalt carbonate,cobalt oxide(Co3O4),and the mixture of basic cobalt carbonate and cobalt oxide were investigated by means of microwave cavity perturbation,their temperature increasing curves were measured,and their ability to absorb microwave energy was also assessed based on the temperature increasing behavior of the material exposed to microwave field.Analyses of spectrum attenuation and relative frequency shift show that basic cobalt carbonate has weak capability to absorb microwave energy,while cobalt oxide has very strong capability to absorb microwave energy.It is feasible to thermally decompose basic cobalt carbonate though addition of small amount of cobalt oxide in microwave fields.The capability to absorb microwave energy of sample increases with an increase in mixing ratio of Co3O4. 展开更多
关键词 basic cobalt carbonate cobalt oxide (Co3O4) MICROWAVE temperature increasing behavior absorption
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Effects of Alginate Gel on Rheological Properties of Hair-tail (Trichiurus lepturus) Surimi 被引量:2
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作者 XUE Yong LIU Xin ZHANG Lili LIN Dan XU Jiachao XUE Changhu 《Journal of Ocean University of China》 SCIE CAS 2011年第2期191-196,共6页
Effects of alginate gel at different concentrations on rheological properties of hair-tail (Trichiurus lepturus) surimi were investigated. Alginate gel (1% - 3%) exhibited enhanced effects, especially when alginate ge... Effects of alginate gel at different concentrations on rheological properties of hair-tail (Trichiurus lepturus) surimi were investigated. Alginate gel (1% - 3%) exhibited enhanced effects, especially when alginate gel concentration increased. The rheological properties of mixture samples were studied by the time sweep, frequency sweep and temperature sweep. The critical strain values of the mixture samples for the onset of non-linear viscoelasticity were about 5%. The storage modulus G' of the mixture samples increased with time for 4 h. The frequency sweep showed that G' was greater than G" for all the mixture gels with different alginate gel concentrations, and values of both n' and n" for all samples were low (<0.2), these constants corresponding to G' and G", and indicating the elasticity of mixture gels. The values of storage modulus G' decreased during heating process and increased with decreasing temperature. 展开更多
关键词 hair-tail surimi alginate gel rheological properties
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Effects of Different NaCl Doses on Morphological and Physiological Parameters in Mentha piperita L.
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作者 Ozlem Altuntas Sebnem Kusvuran Hayriye Yildiz Dasgana 《Journal of Agricultural Science and Technology(A)》 2016年第6期411-416,共6页
Salt stress is one of the most serious limiting factors for crop growth and production. This study was carried out to evaluate the effects of salt stress in four Mentha piperita L. varieties, in greenhouse conditions.... Salt stress is one of the most serious limiting factors for crop growth and production. This study was carried out to evaluate the effects of salt stress in four Mentha piperita L. varieties, in greenhouse conditions. The seedlings were irrigated with 1/2 Hoagland nutrition solutions. Following 10 d of growth in the pots, the seedlings were subjected to salt stress with different concentrations of NaCl (0, 50 and 100 mM, respectively). Responses of the mint varieties to salt stress were evaluated using some plant growth and physiological parameters, such as plant height, root length, shoot and root fresh and dry weight, and ion concentrations in leaves, such as Na, K, Ca and Cl. Salt stress caused reduction in physiological parameters. However, this reduction was significant at 100 mM NaCl compared to 50 mM NaCl. These two concentrations of NaCl increased Na and Cl contents in leaves. However, K and Ca contents were decreased with salinity. The results showed that Mentha piperita cv. Sewiss and Granada were found more tolerant to salt stress than cv. Marokko and Citaro. 展开更多
关键词 GROWTH Menthapiperita L. mineral nutrition salt stress seedlings.
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Quantum discord in three-spin XXZ chain with three-spin interaction 被引量:2
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作者 YUE HaiDi ZHANG Yong GONG Jian 《Science China(Physics,Mechanics & Astronomy)》 SCIE EI CAS 2012年第9期1641-1645,共5页
Quantum discord, as a kind of measurement of quantum correlation, has received much attention since it was introduced. This paper focuses on studying quantum discord in three-spin XXZ chain with three-spin interaction... Quantum discord, as a kind of measurement of quantum correlation, has received much attention since it was introduced. This paper focuses on studying quantum discord in three-spin XXZ chain with three-spin interaction. The effects of all kinds of pa- rameters on quantum discord in the ferromagnetic region J=-I are studied. The three-spin interaction may increase the value of quantum discord between two spins, while the anisotropy may decrease the value. In addition, the regrowth of quantum discord with temperature is found in the model. For zero temperature, quantum phase transition is existent. 展开更多
关键词 quantum discord three-spin interaction XXZ-spin chain
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A Meta-analysis of the Effects of Warming and Elevated CO_2 on Soil Microbes 被引量:7
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作者 FU Gang ZHANG Haorui +1 位作者 LI Shaowei SUN Wei 《Journal of Resources and Ecology》 CSCD 2019年第1期69-76,共8页
Soil microbes play important roles in terrestrial ecosystem carbon and nitrogen cycling. Climatic warming and elevated CO2 are two aspects of climatic change. In this study, we used a meta-analysis approach to synthes... Soil microbes play important roles in terrestrial ecosystem carbon and nitrogen cycling. Climatic warming and elevated CO2 are two aspects of climatic change. In this study, we used a meta-analysis approach to synthesise observations related to the effects of warming and elevated CO2 on soil microbial biomass and community structure. Ecosystem types were mainly grouped into forests and grasslands. Warming methods included open top chambers and infrared radiators. Experimental settings included all-day warming, daytime warming and nighttime warming. Warming increased soil actinomycetes and saprotrophic fungi, while elevated CO2 decreased soil gram-positive bacteria(G+). Mean annual temperature and mean annual precipitation were negatively correlated with warming effects on gram-negative bacteria(G–) and total phospholipid fatty acid(PLFA), respectively. Elevation was positively correlated with the warming effect on total PLFA, bacteria, G+ and G–. Grassland exhibited a positive response of total PLFA and actinomycetes to warming, while forest exhibited a positive response in the ratio of soil fungi to bacteria(F/B ratio) to warming. The open top chamber method increased G–, while the infrared radiator method decreased the F/B ratio. Daytime warming rather than all-day warming increased G–. Our findings indicated that the effects of warming on soil microbes differed with ecosystem types, warming methods, warming times, elevation and local climate conditions. 展开更多
关键词 ecosystem types elevated CO2 increased temperature response ratio warming methods
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宇宙也在不断变热
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《晚晴》 2021年第2期59-59,共1页
近期,《天体物理学杂志》刊登了一项研究成果,通过对比不同时期宇宙中星系团周围的气体温度,发现在过去100亿年间,星系团周围气体的温度增加了将近10倍,达到了现在的约200万摄氏度。那么,宇宙也在变热吗?实际上,宇宙浩瀚无垠,绝大多数... 近期,《天体物理学杂志》刊登了一项研究成果,通过对比不同时期宇宙中星系团周围的气体温度,发现在过去100亿年间,星系团周围气体的温度增加了将近10倍,达到了现在的约200万摄氏度。那么,宇宙也在变热吗?实际上,宇宙浩瀚无垠,绝大多数空间空无一物,温度也极其寒冷。然而,在一些宇宙天体如太阳附近,气体温度却可高达百万摄氏度,上文提到的温度变化研究也是指位于星系团周围的类似高温区域。 展开更多
关键词 星系团 天体物理学 温度变化 气体温度 太阳附近 温度增加 浩瀚无垠 周围气体
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