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Integrative Conservation, Volume 3, Issue 4, Page 294-311, December 2024.Freshwater biodiversity in China is threatened by multiple anthropogenic factors, and while there are some reasons to suppose it may be possible to bend the curve of biodiversity loss, the variety of threats and their likely interactions with ongoing climate change provide little basis for optimism. For example, the historic overexploitation of Yangtze
David Dudgeon
wiley +1 more source
吐鲁番盆地一次极端高温天气过程分析 An Analysis of Extremely Hot Weather Process on Turpan Basin
, 2013 本文对2010年6月15日~6月22日吐鲁番盆地出现的连续高温天气进行了分析，结果表明：此次高温天气主要是由于受深厚暖高脊持续控制，新疆脊与西太平洋副高在新疆叠加形成闭合高压中心，高压系统区存在较强的下沉运动引起的；同时由于盆地地形特有的聚热作用与地面热低压东移的共同影响，盆地高温出现增幅。 In this paper, a continuous hot weather process was analyzed on Turpan basin from June 15 to June 22, 2010.
余华, 张慧琴, 杨扬
semanticscholar +1 more source
野生动物学报, 2016 为研究夏季高温环境是否对小熊猫的生理机能产生影响,在2013年6～8月期间对小熊猫的体温和心率于上、下午进行测量,体重约隔15 d空腹进行称量,并于高温开始前后采血测定生化指标碱性磷酸酶(AKP)、磷酸激酶(CK)、谷丙转氨酶(ALT)、谷草转氨酶(AST)。结果表明:6月与7、8月间的温度存在显著差异,因而6月与7、8月可认为是夏天高温开始前、后的阶段。小熊猫个体间的体温存在差异,不同月份间的体温、心率不存在显著差异,随着环境温度升高小熊猫的体温、心率未随之有显著变化,体重也未明显减轻 ...
汪丽芬 俞红燕 朱 岩 孙伟明
doaj
Zhejiang Daxue xuebao. Lixue ban, 2018 青藏高原和印度洋均对我国气候有重要影响，研究高原和印度洋的热力状况及其耦合关系对全面了解我国的天气现象具有重要意义.利用1981 — 2010年(30 a)欧洲中心ERA-interim的青藏高原和印度洋温度资料，以及NCEP/NCAR的垂直速度和风速资料，分析了青藏高原地气温差和印度洋海气温差的特征及其相互影响.结果表明，高原冬、夏季地气温差有所区别：冬季地气温差呈东北-西南向的带状分布，在高原中部、西南边界喜马拉雅山脉地区和东南边界出现了较大的负值中心，其他地区均为正值；夏季地气温差均为正值 ...
SHENZiwei(申紫薇) +2 more
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Kinetic Investigations and Experimental Determination of Phase Equilibria in some Nickle-Based superalloys [PDF]
, 2016 镍基高温合金具有优异的综合性能，能够适应长时间的高温环境服役要求，广泛应用于航空工业中，其中航空发动机中的镍基高温合金用量最高，所用比例达到了40%-50%。随着航空工业的不断发展，航空发动机对工作温度、推重比及使用寿命的要求进一步提高，高温合金的成分设计面临着新的挑战。相图和动力学计算是材料设计的基础，它使材料工作者摆脱了过去低效的“炒菜式”的材料设计理念，对高温合金的设计研发具有重要的意义。本研究采用扩散偶法，对Ni-Co-Al三元体系的扩散行为进行了研究；基于文献中的实验数据，对Ni-W-X(X ...
杨应来
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The enigmatic life history of the bamboo explained as a strategy to arrest succession
Ecological Monographs, Volume 94, Issue 4, November 2024.Abstract Bamboos are perennial woody grasses that display an enigmatic mix of traits. Bamboo is highly shade intolerant like early‐successional trees. Without secondary xylem, bamboos cannot continue to grow once they reach a maximum height or replace xylem damaged by hydraulic stress and must instead replace each stem after a few years using ...
Aiyu Zheng, Stephen W. Pacala
wiley +1 more source
Jianzhu Gangjiegou Jinzhan, 2021 螺纹锚固单边螺栓是指通过带有螺纹的特殊螺栓孔代替螺母,从而实现单侧安装、拧紧功能的一种螺栓。目前关于该种螺栓连接T形节点在常温下不同破坏模式的受拉承载力计算方法已有研究。但在高温条件下节点变形增大,且高强螺栓与普通钢材在高温下的材性折减规律不一致,导致现有的常温计算公式不能直接用于火灾高温情况,目前仍缺少计算该类节点在高温下承载力的计算方法。根据常温下承载力计算公式,结合高温下节点出现大变形的特点,对现有的计算公式进行修正。并根据现有的试验结果对修正公式进行验证 ...
鲁永贵 +4 more
doaj
Deflection of Sodium-Silicate Self-Hardening Mold at a High Temperature [PDF]
, 1977 In order to appreciate the movement of the mold wall by the pressure of the poured molten metal, the deflection test at a high temperature is usually adopted.Therefore in these experiments, the authors have investigated about the properties of the self ...
中田 登志夫, 養田 実
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Biotropica, Volume 56, Issue 6, November 2024.This study examines the distribution and environmental correlations of 1081 large old trees (LOTs) across 74 species in Hainan Island, South China. The findings reveal uneven spatial patterns, with species diversity varying across the island and influenced by factors such as GDP, urbanization, and forest cover.
Chunping Xie +3 more
wiley +1 more source
Maxwell分布に基づく反応速度の温度依存性のシミュレーション [PDF]
, 2019 A particle kinetic energy probability distribution eqn. (5) is lead from Maxwell distribution. Based on the eqn. (5), the proportion of number of the molecules bearing kinetic energy above a certain activation energy is calculated by two methods, and is ...
中島, 敏
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