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Lightning in a Forest (Wild) Fire: Mechanism at the Molecular Level
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作者 See Leang Chin xueliang guo +4 位作者 Harmut Schroeder Huanbin Xu Tie-Jun Wang Ruxin Li Weiwei Liu 《Atmospheric and Climate Sciences》 2024年第1期128-135,共8页
The mechanism of lightning that ignites a forest fire and the lightning that occurs above a forest fire are explained at the molecular level. It is based on two phenomena, namely, internal charge separation inside the... The mechanism of lightning that ignites a forest fire and the lightning that occurs above a forest fire are explained at the molecular level. It is based on two phenomena, namely, internal charge separation inside the atmospheric cloud particles and the existence of a layer of positively charged hydrogen atoms sticking out of the surface of the liquid layer of water on the surface of rimers. Strong turbulence-driven collisions of the ice particles and water droplets with the rimers give rise to breakups of the ice particles and water droplets into positively and negatively charged fragments leading to charge separation. Hot weather in a forest contributes to the updraft of hot and humid air, which follows the same physical/chemical processes of normal lightning proposed and explained recently[1]. Lightning would have a high probability of lighting up and burning the dry biological materials in the ground of the forest, leading to a forest (wild) fire. The burning of trees and other plants would release a lot of heat and moisture together with a lot of smoke particles (aerosols) becoming a strong updraft. The condition for creating lightning is again satisfied which would result in further lightning high above the forest wild fire. 展开更多
关键词 Forest Wild Fire LIGHTNING Molecular Level
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Charging Mechanism of Lightning at the Molecular Level
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作者 See Leang Chin xueliang guo +6 位作者 Harmut Schroeder Di Song Andong Xia Fan’ao Kong Huanbin Xu Tiejun Wang Ruxin Li 《Atmospheric and Climate Sciences》 2023年第4期415-430,共16页
Cloud electrification is one of the oldest unresolved puzzles in the atmospheric sciences. Though many mechanisms for charge separation in clouds have been proposed, a quantitative understanding of their respective co... Cloud electrification is one of the oldest unresolved puzzles in the atmospheric sciences. Though many mechanisms for charge separation in clouds have been proposed, a quantitative understanding of their respective contribution in a given meteorological situation is lacking. Here we suggest and analyze a hitherto little discussed process. A qualitative picture at the molecular level of the charge separation mechanism of lightning in a thundercloud is proposed. It is based on two key physical/chemical natural phenomena, namely, internal charge separation of the atmospheric impurities/aerosols inside an atmospheric water cluster/droplet/ice particle and the existence of liquid water layers on rimers (graupels and hailstones) forming a layer of dipoles with H<sup>+</sup> pointing out from the air-water interface. Charge separation is achieved through strong collisions among ice particles and water droplets with the rimers in the turbulence of the thundercloud. This work would have significant contribution to cloud electrification and lightning formation. 展开更多
关键词 Cloud Electrification Charge Separation COLLISION Molecular Level
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华北中部夏季气溶胶垂直分布及其与云凝结核和云滴转化关系的飞机观测研究 被引量:2
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作者 李义宇 郭学良 +4 位作者 金莲姬 李培仁 孙鸿娉 赵德龙 马新成 《大气科学》 CSCD 北大核心 2022年第4期845-858,共14页
气溶胶的时空分布及其核化成云的转化过程是云降水物理研究的重点,也是气候变化中气溶胶间接效应关注的热点问题。利用2013~2014年期间在华北中部山西地区开展的9架次夏季晴天和积云天气情况下的气溶胶、云凝结核(CCN)及云滴数浓度观测... 气溶胶的时空分布及其核化成云的转化过程是云降水物理研究的重点,也是气候变化中气溶胶间接效应关注的热点问题。利用2013~2014年期间在华北中部山西地区开展的9架次夏季晴天和积云天气情况下的气溶胶、云凝结核(CCN)及云滴数浓度观测资料,分析研究了气溶胶的垂直分布、谱分布、来源特征及其与云凝结核、云滴数浓度的转化关系。研究结果表明,大气边界层逆温层结对气溶胶、CCN垂直分布有重要影响,不同天气条件下气溶胶谱型在低层差异较大而高层基本一致;垂直方向上CCN数浓度与气溶胶数浓度有较好的相关性,过饱和度0.3%条件下CCN比率(云凝结核/凝结核)与气溶胶有效直径呈线性关系;积云云下气溶胶与云滴的线性拟合方程为y=1.3x-616.3,拟合相关系数为0.96,气溶胶转化为云滴的比率可达到47%。在过饱和度0.3%条件下,云下CCN与云滴的线性拟合方程为y=1.6x-473.8,拟合相关系数也为0.96,CCN转化为云滴的比率可达到69%。 展开更多
关键词 气溶胶 云凝结核(CCN) 云滴数浓度 飞机观测 华北中部
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养殖密度对豹纹鳃棘鲈生长和血液生化指标的影响 被引量:8
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作者 林琳 孙学亮 +4 位作者 邢克智 郭永军 陈成勋 于学权 王庆奎 《水产科学》 CAS CSCD 北大核心 2017年第1期83-87,共5页
为探究养殖密度对湿体质量为(132.75±0.51)g的豹纹鳃棘鲈生长和血液生化指标的影响,设计了低(9.34kg/m3)、中(19.23kg/m3)、高(37.22kg/m3)3个养殖密度,每个密度设3个重复,连续饱食投喂56d后取样,测定相关指标。试验结果表明,37.22... 为探究养殖密度对湿体质量为(132.75±0.51)g的豹纹鳃棘鲈生长和血液生化指标的影响,设计了低(9.34kg/m3)、中(19.23kg/m3)、高(37.22kg/m3)3个养殖密度,每个密度设3个重复,连续饱食投喂56d后取样,测定相关指标。试验结果表明,37.22kg/m3组的终末体质量、平均质量增加率和特定生长率均显著低于其他两组(P<0.05),而9.34kg/m3、19.23kg/m3组间差异不显著(P>0.05);养殖密度对饲料系数、摄食率、瞬时生长率和热量单位生长系数无显著影响(P>0.05)。血清总超氧化物歧化酶的活力在37.22kg/m3组最高,19.23kg/m3组最低,且各密度组间差异显著(P<0.05);37.22kg/m3组血清总抗氧化能力显著低于其他两组(P<0.05),19.23kg/m3组高于9.34kg/m3组,但差异不显著(P>0.05);37.22kg/m3组血清丙二醛显著高于其他两组(P<0.05),而其他两组间差异不显著(P>0.05);乳酸脱氢酶随养殖密度的升高显著增加,且各密度组间差异显著(P<0.05);37.22kg/m3组谷丙转氨酶、谷草转氨酶显著高于其他两组(P<0.05),而37.22kg/m3组的溶菌酶活性显著低于其他两组(P<0.05),其他两组间差异不显著(P>0.05);养殖密度对血浆葡萄糖、胆固醇、C反应蛋白、总蛋白、乳酸无显著影响。 展开更多
关键词 养殖密度 豹纹鳃棘鲈 生长 血液生化指标
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