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基于弹性稳定约束的桁架臂顶节铰点布局优化研究 被引量:2
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作者 王欣 王成林 +1 位作者 周杨 徐金帅 《中国机械工程》 EI CAS CSCD 北大核心 2013年第1期41-46,51,共7页
运用铁摩辛柯弹性稳定性理论,将桁架臂结构简化成铁摩辛柯梁形式,并以最小屈曲储存应变能为目标函数建立数学模型。针对该模型,在MATLAB环境下编制了优化分析程序,并运用改进的遗传算法对桁架臂顶节铰点布局优化问题进行求解,然后对比... 运用铁摩辛柯弹性稳定性理论,将桁架臂结构简化成铁摩辛柯梁形式,并以最小屈曲储存应变能为目标函数建立数学模型。针对该模型,在MATLAB环境下编制了优化分析程序,并运用改进的遗传算法对桁架臂顶节铰点布局优化问题进行求解,然后对比分析桁架臂优化前后的稳定性,以确定该数学模型是否合理。研究结果表明,优化模型是合理的,它为解决桁架臂顶节铰点布局方案优化问题提供了一种新的更有效的途径。 展开更多
关键词 桁架臂顶节铰点 布局优化 弹性稳定性 改进的遗传算法
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柬埔寨的加顶节
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作者 朱惠芬 《印度支那》 1986年第2期39-,共1页
柬埔寨有许多传统的宗教节日,其中“加顶”书是柬埔寨佛教徒最隆重的节日之一。每年佛历十月二十八日是僧侣们结束雨季斋期的开禁节“真卜沙”。翌日,佛历十一月初一,便是为期一个月的“加顶”节的开始。在整整一个月中。
关键词 佛历 顶节 宗教节日 释迎牟尼 卜名 三一 鼓面 罗伞 有关费用 唱山歌
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巧取海竿顶节走线环
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作者 孙海龙 《中国钓鱼》 2000年第9期21-21,共1页
关键词 钓鱼 海竿 顶节 走线环 钓具
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水稻穗颈极度缩短突变体sui(t)的遗传分析与基因定位 被引量:5
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作者 王晓雯 苗润隆 +5 位作者 蒋钰东 杜川 杨正林 凌英华 何光华 桑贤春 《西南大学学报(自然科学版)》 CAS CSCD 北大核心 2013年第5期1-6,共6页
来源于EMS处理籼型恢复系缙恢10号的穗颈节间极度缩短突变体其他节间与恢复系缙恢10号无显著变化,表现为全包穗,对GA3不敏感,暂命名为sui(t).遗传分析表明变异性状受一对隐性核基因控制.以中花11/sui(t)的F2隐性单株为定位群体,将sui(t... 来源于EMS处理籼型恢复系缙恢10号的穗颈节间极度缩短突变体其他节间与恢复系缙恢10号无显著变化,表现为全包穗,对GA3不敏感,暂命名为sui(t).遗传分析表明变异性状受一对隐性核基因控制.以中花11/sui(t)的F2隐性单株为定位群体,将sui(t)基因定位在第1染色体SSR标记RM5336,RM3425向短臂末端一侧,进一步合成SSR,Indel等标记,最终将sui(t)基因定位在RM3148和C1In002(swu)之间,遗传距离分别为0.8cM和1.4cM,物理距离为382kb,为下一步基因克隆和功能研究奠定了基础. 展开更多
关键词 水稻 顶节间极度缩短 全包穗 GA3不敏感 基因定位
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不同节位摘顶对日光温室厚皮甜瓜叶片衰老的影响 被引量:7
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作者 王冰林 李成军 +3 位作者 何启伟 刘世琦 焦自高 丁永霞 《中国农学通报》 CSCD 2007年第8期306-310,共5页
以日光温室栽培的蜜世界、鲁厚甜2号厚皮甜瓜品种为试材,通过分析不同摘顶植株叶片可溶性蛋白质(Pr)、叶绿素(Chl)、丙二醛(MDA)含量以及过氧化物酶(POD)活性变化,探讨了不同节位摘顶对厚皮甜瓜叶片衰老的影响。结果表明,在授粉后7d以内... 以日光温室栽培的蜜世界、鲁厚甜2号厚皮甜瓜品种为试材,通过分析不同摘顶植株叶片可溶性蛋白质(Pr)、叶绿素(Chl)、丙二醛(MDA)含量以及过氧化物酶(POD)活性变化,探讨了不同节位摘顶对厚皮甜瓜叶片衰老的影响。结果表明,在授粉后7d以内,两品种第18节、24节摘顶可使座瓜节位叶片维持较高的生理活性,第30节摘顶则明显偏低,表现为:前者叶片Pr、Chl含量明显高于后者,而MDA含量、POD活性则较低。授粉14d之后,两品种第24节摘顶延缓叶片衰老的效果明显优于第18节、30节摘顶。植株摘顶后,不同节位叶片生理指标的变化进一步证实,第24节摘顶可明显延缓叶片衰老。综合分析表明,24节左右为厚皮甜瓜合理摘顶节位,早熟品种可适当提高摘顶节位,而中晚熟品种应适当降低节位。 展开更多
关键词 日光温室 厚皮甜瓜 顶节 叶片衰老
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不同节位摘顶对热带设施栽培甜瓜生长及品质的影响 被引量:1
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作者 杨小锋 曹明 +2 位作者 黄植 杨光华 张雪彬 《广东农业科学》 CAS 2015年第22期28-31,共4页
以"南海蜜"哈密瓜品种为试材,采用无土栽培方式研究了不同摘顶节位对甜瓜生长、产量和品质的影响。结果表明,随着摘顶节位的升高,甜瓜果形指数呈现先降低后增加趋势;单叶面积、可溶性糖含量、中心可溶性固形物、边缘可溶性固... 以"南海蜜"哈密瓜品种为试材,采用无土栽培方式研究了不同摘顶节位对甜瓜生长、产量和品质的影响。结果表明,随着摘顶节位的升高,甜瓜果形指数呈现先降低后增加趋势;单叶面积、可溶性糖含量、中心可溶性固形物、边缘可溶性固形物均呈现增加趋势;而单果重和果实维生素C含量呈先增加后降低的趋势;适宜摘顶节位有利于提高甜瓜产量和改善品质。综合考虑设施甜瓜果形指数、单叶面积、单果重、可溶性糖含量、可溶性蛋白含量、中心可溶性固形物及边缘可溶性固形物等指标,热带设施甜瓜适宜摘顶节位为26节。建议热带设施甜瓜生产大棚肩高设计高度为2 m。 展开更多
关键词 甜瓜 热带设施栽培 顶节 生长 品质
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牧草新品种
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作者 赵文翰 《河南科技》 2002年第10X期9-9,共1页
吉农朝鲜碱茅是吉林省农科院畜牧分院草地所从野生朝鲜碱茅中采用系统选育方法育成的新品种。该品种为禾本科碱茅属多年生丛生型牧草,株高80~100厘米,茎直立或屈曲,有2~3节,顶节位于下部1/3处。叶片线形,扁平或内卷,叶长3~8厘米,宽2... 吉农朝鲜碱茅是吉林省农科院畜牧分院草地所从野生朝鲜碱茅中采用系统选育方法育成的新品种。该品种为禾本科碱茅属多年生丛生型牧草,株高80~100厘米,茎直立或屈曲,有2~3节,顶节位于下部1/3处。叶片线形,扁平或内卷,叶长3~8厘米,宽2~3毫米。圆锥花序开展,长10~16厘米。种子纺锤形,紫褐色,千粒重0.1~0.14克。吉农朝鲜碱茅保持了野生朝鲜碱茅的耐盐碱、抗寒、耐旱的特点,在土壤酸碱度9.5以上、表土含盐量1.5%、年降水量400毫米的条件下能正常生长。 展开更多
关键词 朝鲜碱茅 牧草新品种 选育方法 丛生型 碱茅属 紫褐色 顶节 禾本科草 土壤酸碱度 疏丛型
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Ultrastructural Changes of Scolex on Cysticercus pisiformis during Relative Rest and Motion States 被引量:2
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作者 潘耀谦 张柳平 +5 位作者 王帅 李瑞珍 刘志科 孙玉倩 Javaid Ali Gadahi 刘兴友 《Agricultural Science & Technology》 CAS 2014年第1期111-115,共5页
[Objective] This study aimed to research the ultra-morphological changes of scolex of Cysticercus pisiformis during the relative rest and motion states. [Method] The ultrastructure changes of scolex located in cyst an... [Objective] This study aimed to research the ultra-morphological changes of scolex of Cysticercus pisiformis during the relative rest and motion states. [Method] The ultrastructure changes of scolex located in cyst and evaginated from cyst after cultivation were comparatively observed by scanning electron microscope. [Result] When the scolex was in the relative rest state, observed from the top, the rostel um with the tegument muscular column that connected to tooth-hook looked like the umbrel a and covered on the front end of the scolex. Viewed from the side of the scolex, the tooth-hook on the rostel um looked like the antler branch and had only one row. Four suckers looked like cavities, and were located in the back of the rostel um and distributed around the scolex in the equidistance. When the scolex was in the motion states, the tegument muscular column on the rostel um contracted, the antler-like tooth-hook extended to periphery, and the sucker also made the ring-like and longitudinal-like contraction. [Conclusion] Ultrastructure of the scolex of C. pisiformis changed apparently during relative rest and motion states. Those changes help scolex to invade the host tissue. 展开更多
关键词 Cysticercus pisiformis Scolex Rostellum SUCKER ULTRASTRUCTURE
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日本九年桥人行桥下部结构施工
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作者 刘海燕 《世界桥梁》 北大核心 2017年第1期93-94,共2页
九年桥位于日本岩手县北上市下鬼柳四地,横跨和贺川,是一座混凝土桥梁,建于1927年2月。该桥已经使用了近80年,其上交通量仍较大。为更好地服务于市民,对该桥进行维修加固,并在其一侧新建一座人行桥。人行桥桥长331.0m,跨径布置为(51.5... 九年桥位于日本岩手县北上市下鬼柳四地,横跨和贺川,是一座混凝土桥梁,建于1927年2月。该桥已经使用了近80年,其上交通量仍较大。为更好地服务于市民,对该桥进行维修加固,并在其一侧新建一座人行桥。人行桥桥长331.0m,跨径布置为(51.5+51.6+51.6+44.8+44.8+44.8+44.8+40.7)m。为快速、近距离施工, 展开更多
关键词 跨径布置 下部结构 井筒施工 鬼柳 预制拼装 节段拼装 辅助施工 桥墩基础 加预应力 顶节
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“一三五不论”之我见
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作者 成多 《文史杂志》 2014年第5期114-114,共1页
常听人说对联和律诗、绝句的平仄安排一样是"一三五不论,二四六分明"。想到王力教授当年讲解的科学分析,再举实例以申其义。一、头节首字一般情况,七言首字(顶节首字)可平可仄,例如:"一行白鹭上青天",依平起入韵句式。
关键词 一三 平起 七言 顶节 入韵 王力 拗救 上青天 头节 五言
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诗的节奏问题不容忽视
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作者 何瑞澄 《小学教学参考(语文版)》 1998年第6期19-19,共1页
构成格律诗诗律的四个要素:声、韵、对、节,前面已讲了三个,这里讲到最后一个了.节,就是节奏.诗的节奏有两种:一是按平仄音调来分的,叫表声节奏;一是按短语结构来分的,叫表意节奏.表声节奏,就是每一诗句由左到右两个字划为一个节奏,句... 构成格律诗诗律的四个要素:声、韵、对、节,前面已讲了三个,这里讲到最后一个了.节,就是节奏.诗的节奏有两种:一是按平仄音调来分的,叫表声节奏;一是按短语结构来分的,叫表意节奏.表声节奏,就是每一诗句由左到右两个字划为一个节奏,句末一节只有一个字.五言诗有三个节奏,如“风雪夜归人”.第一节称头节,第二节称腹节,第三节称脚节.七言诗分四个节奏,即在五言的头节上再加个“顶节”,如“清明时节雨纷纷”,“清明”就是顶节. 展开更多
关键词 表声 清明时节雨纷纷 顶节 风雪夜归人 短语结构 五言 腹节 脚节 翠柳 头节
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Effects of tip-pruning treatment on source-sink regulation of Catharanthus roseus seedlings 被引量:1
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作者 GAO Yang ZHANG Xue-ke GUO Xiao-rui SUN Yan-fei ZU Yuang-gang 《Journal of Forestry Research》 SCIE CAS CSCD 2006年第4期326-328,共3页
Fifty cultivated Catharanthus roseus seedlings were selected for tip-pruning treatment and the effects of tip-pruning on seedling growth and source-sink regulation were investigated for revealing physiological mechani... Fifty cultivated Catharanthus roseus seedlings were selected for tip-pruning treatment and the effects of tip-pruning on seedling growth and source-sink regulation were investigated for revealing physiological mechanisms of plants. The results showed that tip-pruning treatment resulted in obvious inhibition of apical dominance and enhancement of branching numbers. The contents of soluble sugars, acid sucrose invertase activity (AI) had a great change in differently positional leaves of the seedling. The sink strength in tip leaves of seedlings dramatically declined after tip-pruning treatment, while that in the leaves at the middle and bottom of seedlings had no obvious changes. The inhibition of apical dominance of tip leaves of seedlings was caused by the diminished sink strength due to tip-pruning treatment, 展开更多
关键词 Catharanthus roseus (L.) G. Don Source-sink regulation Tip-pruning Apical dominance
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Link-Vertex Topology Aggregation for Multi-domain Path Computation with Hierarchical PCE Architecture 被引量:1
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作者 Peng Yunfeng Chen Zhen +2 位作者 Zhao Changming Wang Zongwei Long Keping 《China Communications》 SCIE CSCD 2012年第1期86-91,共6页
Inter-domain path computing is one big issue in multi-domain networks. The Hierarchical Path Computing Element (H-PCE) is a semi-central architecture for computing inter-domain path. To facilitate H-PCE in inter-domai... Inter-domain path computing is one big issue in multi-domain networks. The Hierarchical Path Computing Element (H-PCE) is a semi-central architecture for computing inter-domain path. To facilitate H-PCE in inter-domain path computing, this paper proposed a topology aggregation scheme to abstract the edge nodes and their connected inter-domain link as one vertex to achieve more optimal paths and confidentiality guarantee. The effectiveness of the scheme has been demonstrated on solving wavelength routing in multi-domain Wavelength Division Multiplexing (WDM) network via simulation. Simulation results show that this scheme reduces at least 10% inter-domain blocking probability, compared with the traditional Domain-to-the-Node (DtN) scheme. 展开更多
关键词 ROUTING PCE link-vertex aggregation inter-domain path computation multi-domain network topology aggregation
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Analysis of Energy Saving Achievable through Solar Photovoltaic Systems on School Roofs: A Case of the City of Rome
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作者 Livio de Santoli Gino Moncada Lo Giudice Fabio Fraticelli Filippo Fornari Claudia Calice 《Journal of Energy and Power Engineering》 2014年第3期448-452,共5页
Embracing renewable energy technology makes a lot of sense for the public sectors and schools as it meets the government sustainability goals and provides a financially viable means of achieving carbon savings while o... Embracing renewable energy technology makes a lot of sense for the public sectors and schools as it meets the government sustainability goals and provides a financially viable means of achieving carbon savings while offering income potential. This study is aimed to quantify the achievable energy saving by spread use ofphotovoltaic systems on public building stock in the city of Rome. The installation of PV (photovoltaic) systems in the historic center depends on the feasibility conditions, generally more complex compared to the cases examined in the consolidated city, because they require compliance with the formal and aesthetic characteristics of the buildings, so the choice must be made between compatible components, which allow to minimize the transformation. The suburbs are characterized by large plane roofs in bad conditions and belonging to isolated buildings, so the useful surface, according to shading condition, offers a big potential for renewable technologies. The research provides an evaluation of maximum production of solar energy and the subsequent energy saving and reduction of greenhouse gasses, using parametric data, and an evaluation of the cost-effectiveness, with a rough calculation of return on investment. 展开更多
关键词 SCHOOLS photovoltaic systems energy saving solar energy sustainability.
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Seasonal variations of night mesopause temperature in Beijing observed by SATI4 被引量:5
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作者 XIONG JianGang WAN WeiXing +4 位作者 NING BaiQi LIU LiBo WU BaoYuan HU LianHuan XU Tao 《Science China(Technological Sciences)》 SCIE EI CAS 2012年第5期1295-1301,共7页
The data observed by a spectral airglow temperature imager (SATI) at Beijing National Observatory of Space Environment from July 23, 2008 to July 3l, 2009 are used to study night mesopause temperature in Beijing. Fr... The data observed by a spectral airglow temperature imager (SATI) at Beijing National Observatory of Space Environment from July 23, 2008 to July 3l, 2009 are used to study night mesopause temperature in Beijing. From variations of temperature at 87 and 94 km obtained from OH (6-2) and 02 (0-1) airglow spectra, temperature at night is shown lowest in the summer and highest in the winter. In summer, average temperature at 87 km is 173.9 K, lower than average temperature 180.1 K at 94 km. But in winter, average temperature at 87 Ion is 201.2 K, higher than average temperature 194.8 K at 94 kin. The altitude of mesopause in Beijing is below 87 km in summer and above 94 km in winter. There are about 120-150 days when the mesopause locates below 87 km, which is in agreement with the results of SABER/TIMED. Variations of temperatures at 87 and 94 km are analyzed by harmonic method. Our results show that amplitudes of annual oscillation of temperature at 87 and 94 km are 17.5 and 7.8 K respectively. Amplitudes of semi-annual oscillation at 87 and 94 km are 1.6 and 5.3 K, which are smaller than those of annual oscillation. Although there are differences among different observations because of different locations and different instruments, our results are in general agreement with observation at similar latitude as Beijing. 展开更多
关键词 MESOPAUSE TEMPERATURE AIRGLOW seasonal variations SATI
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Therapeutic observation of 'warming-unblocking needling technique'for knee osteoarthritis due to deficiency of liver and kidney 被引量:5
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作者 Zhang Guoxiao Zhao Yao-dong +1 位作者 Zhu Ling Zhang Fu-qing 《Journal of Acupuncture and Tuina Science》 CSCD 2020年第2期143-148,共6页
Objective:To compare the clinical efficacy between'warming-unblocking needling technique7 and reinforcing method by twirling in treating knee osteoarthritis(KOA)due to deficiency of liver and kidney.Methods:A tota... Objective:To compare the clinical efficacy between'warming-unblocking needling technique7 and reinforcing method by twirling in treating knee osteoarthritis(KOA)due to deficiency of liver and kidney.Methods:A total of 72 patients with KOA were divided into a warming-unblocking group and a reinforcing group by complete randomized method,with 36 cases in each group.Xuehai(SP 10),Heding(EX-LE 2),Liangqiu(ST 34);Neixiyan(EX-LE 4),Xizhong(Extra),Dubi(ST 35),Yinlingquan(SP 9),Zusanli(ST 36)and Yanglingquan(GB 34)were the main points in both groups.Taichong(LR 3),Taixi(Kl 3)and Sanyinjiao(SP 6)were the combined points.'Warming-unblocking needling technique'was applied in the warming-unblocking group,and reinforcing method by twirling was applied in the reinforcing group.The treatments were performed once a day,10 times as a treatment course,at a 2-day interval between two courses,for 3 courses in total.The scores of Western Ontario and McMaster Universities osteoarthritis index(WOMAC)in the two groups were observed before and after the treatment,and the clinical efficacy was compared.Results:After treatment,the total effective rate was 94.3%in the warming-unblocking group and 87.9%in the reinforcing group,and the difference between the two groups was statistically significant(P<0.05).The component scores of pain,stiffness and daily activities in WOMAC and total WOMAC scores in both groups decreased after treatment(all P<0.01).The component and total WOMAC scores in the warming-unblocking group were lower than those in the reinforcing group(P<0.05 or P<0.01).Conclusion:'Warming-unblocking needling technique' has significant efficacy than reinforcing method by twirling in treating KOA due to deficiency of liver and kidney.It can significantly improve pain,stiffness and daily functional activities of patients. 展开更多
关键词 Acupuncture Therapy Warming-unblocking Needling Technique Point Heding(EX-LE 2) Pain Measurement Osteoarthritis Knee Deficiency of Liver and Kidney
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Investigation of the mesospheric temperature over Fort Collins region
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作者 FAN Xin WENG LiBin +2 位作者 ZHANG JianBin FANG HanXian XIE YanQiong 《Science China(Technological Sciences)》 SCIE EI CAS 2014年第8期1562-1567,共6页
The nightly mean mesospheric temperature profiles between 80 and 107 km, observed by Na lidar, over Fort Collins, Colorado (41°N, 105°W) from 1990 to 2010, are employed to research the temporal and spatial... The nightly mean mesospheric temperature profiles between 80 and 107 km, observed by Na lidar, over Fort Collins, Colorado (41°N, 105°W) from 1990 to 2010, are employed to research the temporal and spatial variations and mesopause. We find that the maximum mean temperature is in summer months above 95 kin, but reverse below 95 kin, and there is a cooler region below 185 K around 97 km in August. The largest seasonal variation is 39.2 K at 81 kin, and the minimum is 6.5 K at 96.5 km. The maximum standard derivation in spring and autumn months are larger than other seasons above 105 kin, but the temperatures in March, June and September are lower than the other months between 82 km and 100 km where winter is the largest season. Moreover, the seasonal variations of the temperature are about 36, 8 and 21 K at 85, 95 and 105 km, respectively, winter is colder and summer is warmer above 97.5 km, but reverse below 92 km. The mesopause height is around 102 km in winter, but 84 km in summer, and the mean speed of decreasing or increasing of the mesopause height is about 5 km/month in spring and autumn months which are about 90 km. The lasting time of the mesopause in winter is near 6 months, longer than other seasons, and the mesopause temperature is about 165 K in cool summer, and 185 K in warm winter. 展开更多
关键词 Na lidar mesospheric temperature MESOPAUSE
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