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动物内温性进化研究进展 被引量:2
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作者 王玉山 王祖望 +1 位作者 王德华 张知彬 《Zoological Research》 CAS CSCD 北大核心 2003年第6期480-487,共8页
对动物内温性进化的研究进行了较为系统的论述 ,包括内温性动物概念的由来、特点和起源的选择因子。内温性起源的选择因子包括 8个模型 :热生态位扩展模型、恒温与代谢效率模型、降低个体大小模型、姿势改变模型、增加脑大小模型、有氧... 对动物内温性进化的研究进行了较为系统的论述 ,包括内温性动物概念的由来、特点和起源的选择因子。内温性起源的选择因子包括 8个模型 :热生态位扩展模型、恒温与代谢效率模型、降低个体大小模型、姿势改变模型、增加脑大小模型、有氧呼吸能力模型、双亲行为模型和同化能力模型。其中后 3个模型较为重要。有氧呼吸能力模型认为 ,选择提高支持物理运动的最大呼吸能力 ,而增加的静止代谢作为其相关反应而得以进化。该假说得到种内研究数据的支持 ,而种间的数据并不完全支持。双亲行为模型是指在鸟兽类中 ,内温性是对双亲行为选择的结果 ,因为内温性为双亲控制抚育温度提供了保证。同化能力模型认为 ,在鸟类和兽类中内温性进化由以下两个因素所推动 :①子代出生后双亲行为加强 ;②为支持每日总体能量高速消耗所需 ,动物内脏器官能力增强而导致的较高维持消耗。 展开更多
关键词 内温性进化 选择因子 有氧呼吸能力模型 双亲行为模型 同化能力模型 进化生理学 动物
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外温动物的内温性 被引量:1
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作者 柳劲松 吕建伟 彭巨亮 《高师理科学刊》 2000年第4期48-50,共3页
一些外温动物具有内温性 ,通过行为或生理上的调节 ,使机体的温度高于环境温度 ,提高肌肉和内脏的工作效率 ,有利于捕食和促进消化 ,以更好的适应外界环境.
关键词 外温动物 内温性 生理调节 环境温度
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再谈温血的起源
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作者 刘俊 《化石》 2022年第4期20-23,共4页
现生脊椎动物中内恒温主要出现在鸟类及哺乳动物中。在本刊2016年4期《温血的起源》一文中初步总结了当时的各种证据,讨论了内恒温在两个支系出现的时间。近年来又有了一些新发现,推进了我们的认知。远古生物的体温没有办法直接测量,我... 现生脊椎动物中内恒温主要出现在鸟类及哺乳动物中。在本刊2016年4期《温血的起源》一文中初步总结了当时的各种证据,讨论了内恒温在两个支系出现的时间。近年来又有了一些新发现,推进了我们的认知。远古生物的体温没有办法直接测量,我们只有根据一些与内温性密切相关的性状来推测,尤其是可能在化石中保持下来的性状。在现生动物中有隔膜、心脏为四腔、次生腭、鼻腔冷却、直立的姿势及步态、夜行性、体型小型化、高生长速率、特定的骨骼结构(强烈微脉管化、纤维板层型微观结构、较大个体中的哈氏重建)、脑大、亲代抚育等等。 展开更多
关键词 夜行性 亲代抚育 骨骼结构 现生动物 内温性 生长速率 脊椎动物 直接测量
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研究认为温血动物出现于2.33亿年前
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《科学24小时》 2022年第10期31-31,共1页
近日,科学家们解答了一个关于哺乳动物进化的长期存在的问题——通过对现存哺乳动物和已灭绝哺乳动物及其近亲的耳部解剖,确定温血动物可能起源于约2.33亿年前的晚三叠世。这些基于哺乳动物祖先内耳化石的研究结果,增进了人们对哺乳动... 近日,科学家们解答了一个关于哺乳动物进化的长期存在的问题——通过对现存哺乳动物和已灭绝哺乳动物及其近亲的耳部解剖,确定温血动物可能起源于约2.33亿年前的晚三叠世。这些基于哺乳动物祖先内耳化石的研究结果,增进了人们对哺乳动物演化史的理解。温血性,或称内温性,是哺乳动物和鸟类的一个关键特征,能让它们保持几乎恒定的核心体温,从而生活在各种不同的环境中。 展开更多
关键词 哺乳动物进化 内温性 内耳 晚三叠世 关键特征 灭绝 近亲 解剖
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Effect of thermal storage performance of concrete radiant cooling room on indoor temperature 被引量:1
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作者 辛亚娟 王志强 田喆 《Journal of Central South University》 SCIE EI CAS 2012年第3期709-714,共6页
A building model with radiant cooling system was established and the cooling load, indoor temperature, surface temperature of the wails and other parameters in non-cooling and radiant cooling room were calculated by T... A building model with radiant cooling system was established and the cooling load, indoor temperature, surface temperature of the wails and other parameters in non-cooling and radiant cooling room were calculated by TRNSYS. The comparative analysis of the characteristics of attenuation and delay proves that the operation of radiant cooling system increases the degree of temperature attenuation of the room and reduces the inner surface temperature of the wall significantly, but has little effect on the attenuation coefficient and delay time of wall heat transfer. The simulation results also show that the inner surface temperature of the walls in the radiant cooling room is much lower than that in non-cooling room in the day with the maximum cooling load, which reduces the indoor operation temperature largely, and improves the thermal comfort. Finally, according to the analysis of indoor temperature of the rooms with different operation schedules of cooling system, it can be derived that the indoor mean temperature changes with the working time of radiant cooling system, and the operation schedule can be adjusted in practice according to the actual indoor temperature to achieve the integration of energy efficiency and thermal comfort. 展开更多
关键词 concrete radiant cooling thermal storage performance cooling load operating schedule TRNSYS
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Microscopic Superconductivity and Room Temperature Electronics of High-T_c Cuprates
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作者 LIU Fu-Su CHEN Wan-Fang 《Communications in Theoretical Physics》 SCIE CAS CSCD 2008年第11期1237-1240,共4页
Abstract This paper points out that the Landau criterion for macroscopic superfluidity of He H is only a criterion for microscopic superfluidity of ^4He, extends the Landau criterion to microscopic superconductivity i... Abstract This paper points out that the Landau criterion for macroscopic superfluidity of He H is only a criterion for microscopic superfluidity of ^4He, extends the Landau criterion to microscopic superconductivity in fermions (electron and hole) system and system with Cooper pairs without long-range phase coherence. This paper gives another three non-superconductive systems that are of microscopic superconductivity. This paper demonstrates that one application of microscopic superconductivity is to establish room temperature electronics of the high-To cuprates. 展开更多
关键词 SUPERCONDUCTIVITY Landau criterion long-range phase coherence
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Questionnaire Research on Indoor Environment Quality i n China 被引量:3
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作者 朱能 刘俊杰 《Transactions of Tianjin University》 EI CAS 2003年第2期157-160,共4页
With 1 185 pi eces of questionnaire, it is found that in China, people take fresh air, odor, e tc., as well as indoor air temperature, humidity, as the most important indoor a ir parameters. It is also found that ther... With 1 185 pi eces of questionnaire, it is found that in China, people take fresh air, odor, e tc., as well as indoor air temperature, humidity, as the most important indoor a ir parameters. It is also found that there is a significant sensitivity differen ce in indoor environment between southerners and northerners in China. People fr om different regions have different demands for their working and living environ ment. Therefore, as a good design of air conditioning system, it is strongly rec ommended that the different demands of people from different regions should be t aken into consideration. 展开更多
关键词 indoor air environment QUESTIONNAIRE thermal comfort
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趣闻
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作者 滕玥 《环境经济》 2022年第12期8-9,共2页
哺乳动物恒温性的起源恒温性(或内温性)是哺乳动物和鸟类的一个关键特征。这使它们保持相对稳定的体温,适应不同的生存环境。此前,由于化石证据不够完备,内温性在哺乳动物演化史上最早出现的时间一直难以确定。近日,发表于《自然》的一... 哺乳动物恒温性的起源恒温性(或内温性)是哺乳动物和鸟类的一个关键特征。这使它们保持相对稳定的体温,适应不同的生存环境。此前,由于化石证据不够完备,内温性在哺乳动物演化史上最早出现的时间一直难以确定。近日,发表于《自然》的一项研究指出,哺乳动物的恒温性可能起源于约2.33亿年前的晚三叠世。研究团队分析了56种已灭绝的哺乳动物祖先的内耳半规管结构。 展开更多
关键词 内温性 哺乳动物 研究团队 晚三叠世 《自然》 生存环境 灭绝 关键特征
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图说
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《生物进化》 2022年第3期5-5,共1页
温血性(或称内温性)是哺乳动物和鸟类的一个关键特征,能让它们保持几乎恒定的核心体温,从而生活在各种不同的环境中。内温动物在行为上比冷血外温动物更活跃,能迁徙的距离更远,行动速度也更快;而冷血外温动物普遍速度更慢,较不活跃,有... 温血性(或称内温性)是哺乳动物和鸟类的一个关键特征,能让它们保持几乎恒定的核心体温,从而生活在各种不同的环境中。内温动物在行为上比冷血外温动物更活跃,能迁徙的距离更远,行动速度也更快;而冷血外温动物普遍速度更慢,较不活跃,有氧运动能力偏弱。不过,内温性在哺乳动物演化史上最早出现的时间一直难以确定,因为大部分化石证据都不够完备。最近,古生物学家终于发现,哺乳动物内耳半规管结构的变化(如半规管变窄)可以反映内温性的改变,因为内耳半规管在动物活着时充盈着一种名叫内淋巴液的液体,而内淋巴液的黏度会随动物体温而变化。 展开更多
关键词 内温动物 内温性 有氧运动能力 哺乳动物 外温动物 关键特征 鸟类
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Effects of mild hypothermia on patients with lower intracranial pressure following severe brain injury 被引量:2
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作者 王维平 任海军 +2 位作者 池京洋 徐福林 全勇 《Chinese Journal of Traumatology》 CAS 2005年第1期54-56,共3页
Objective: To study the effects of mild hypothermia therapy on severe brain-injured patients whose intracranial pressure (ICP) could be maintained below 25 mm Hg.Methods: Forty severe brain-injured patients with ICP b... Objective: To study the effects of mild hypothermia therapy on severe brain-injured patients whose intracranial pressure (ICP) could be maintained below 25 mm Hg.Methods: Forty severe brain-injured patients with ICP below 25 mm Hg were divided randomly into one treatment group (n=20, mild hypothermia therapy) and one control group (n=20, normothermia therapy) to observe the changes of the concentration of excitatory amino acids (glutamate and glycine) and cytokines (interleukin-1β and interleukin-6). Results: There were no significant differences in the daily changes of the concentration of excitatory amino acid and cytokines between two groups. The outcome of two groups had no significant differences. Conclusions: Mild hypothermia has no additional beneficial effects on severe brain-injured patients compared with normothermia therapy if ICP can be maintained below 25 mm Hg by using conventional therapy. 展开更多
关键词 Brain injury Intracranial pressure HYPOTHERMIA
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Effect of high temperature annealing on the performance of MANOS charge trapping memory 被引量:4
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作者 JIN Lin ZHANG ManHong +6 位作者 HUO ZongLiang YU ZhaoAn JIANG DanDan WANG Yong BAI Jie CHEN JunNing LIU Ming 《Science China(Technological Sciences)》 SCIE EI CAS 2012年第4期888-893,共6页
We have investigated the effect of post deposition annealing (PDA) temperature of Al2O3 blocking layer on the performance of charge trapping memory capacitors. Two splits of PDA were performed in N2 ambient at 850... We have investigated the effect of post deposition annealing (PDA) temperature of Al2O3 blocking layer on the performance of charge trapping memory capacitors. Two splits of PDA were performed in N2 ambient at 850°C/60 s and 1050°C/60 s, respectively. The 1050°C annealed capacitor could be programmed and erased normally by using Fowler-Nordheim (FN) injection. In contrast, the 850°C annealed device could not be erased, even though it could be programmed properly. By measuring the gate leakage current and the flatband voltage shift, we found the erase failure in the 850°C annealed device was due to a larger gate back-injection leakage current at Vg<0. The trend of gate leakage current was further verified in two Al/Al2O3/SiO2/p-Si control capacitors with the same PDA splits. In addition, constant voltage stress measurements on control capacitors in the FN regime showed that the change of gate leakage current followed an empirical Curie-von Schweidler law at Vg<0. The data pointed out the importance to further study the relation between PDA conditions and the defect generation properties in Al2O3 blocking layer. 展开更多
关键词 charge trapping memory AL2O3 TRAPS ANNEALING
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Effect of hydration on the elasticity of mantle minerals and its geophysical implications 被引量:6
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作者 MAO Zhu LI XinYang 《Science China Earth Sciences》 SCIE EI CAS CSCD 2016年第5期873-888,共16页
Recent studies have shown that major nominally anhydrous minerals in the Earth's mantle, such as olivine, pyroxene and garnet, can incorporate considerable amounts of water as structurally bound hydroxyl. Even a s... Recent studies have shown that major nominally anhydrous minerals in the Earth's mantle, such as olivine, pyroxene and garnet, can incorporate considerable amounts of water as structurally bound hydroxyl. Even a small amount of water is present in mantle minerals, it can strongly affect a number of physical properties, including density, sound velocity, melting temperature, and electrical conductivities. The presence of water can also influence the dynamic behavior, lead to lateral velocity heterogeneities, and affect the material circulation of the Earth's deep interior. In particular, seismic studies have reported the existence of low-velocity zones in various locations of the Earth's upper mantle and transition zone, which has been expected to be associated with the presence of water in the region. In the past two decades, the effect of water on the elasticity and sound velocities of minerals at relevant pressure-temperature(P-T) conditions of the Earth's mantle attracted extensive interests. Combining the high P-T experimental and theoretical mineralogical results with seismic observations provides crucial constraints on the distribution of water in the Earth's mantle. In this study, we summarize recent experimental and theoretical mineral physics results on how water affects the elasticity and sound velocity of nominally anhydrous minerals in the Earth's mantle, which aims to provide new insights into the effect of hydration on the density and velocity profile of the Earth's mantle, which are of particular importance in understanding of water distribution in the region. 展开更多
关键词 Water Elasticity Sound velocity Upper mantle Transition zone Olivine polymorphs
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