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381.
QiuGang Zong YiXin Hao Hong Zou SuiYan Fu XuZhi Zhou Jie Ren LingHua Wang ChongJing Yuan ZhiYang Liu XiangHong Jia Lin Quan Ying Liu YongFu Wang 《中国科学:地球科学(英文版)》2016,59(7):1508-1516
In cases where substorm injections can be observed simultaneously by multiple spacecraft,they can help elucidate the potential mechanisms of particle transport and energization,of great importance to understanding and modeling the magnetosphere.In this paper,using data returned from the BeiDa-IES(BD-IES) instrument onboard a satellite in an inclined(55°) geosynchronous orbit(IGSO),in combination with two geo-transfer orbiting(GTO) satellite Van Allen Probes(A and B),we analyze a substorm injection event that occurred on the 16 th of October 2015.During this substorm injection,the IGSO onboard BD-IES was outbound,while both Van Allen Probe satellites(A and B) were inbound,a configuration of multiple trajectories that provides a unique opportunity to simultaneously investigate both the inward and outward radial propagation of substorm injection.Indicated by AE/AL indices,this substorm was closely related to an IMF/solar wind discontinuity that showed a sharp change in IMF Bz direction to the north.The innermost signature of this substorm injection was detected by Van Allen Probes A and B at L-3.7,while the outermost signature was observed by the onboard BD-IES instrument at L~\0.These data indicate that the substorm had a global,rather than just local,effect.Finally,we suggest that electric fields carried by fast-mode compressional waves around the substorm injection are the most likely candidate mechanism for the electron injection signatures observed in the inner- and outermost inner magnetosphere. 相似文献
382.
Effects of Soil Rhizosphere Aeration on the Root Growth and Water Absorption of Tomato 总被引:3,自引:0,他引:3
Soil rhizosphere aeration status is an important aspect of soil quality and soil ecology. The objective of the current study was to determine the appropriate moisture environment that facilitates rhizosphere soil aeration and ensures normal root respiration in tomato. In the potted experiment, five treatments of soil aeration were used (0.4, 0.8, 1.2, 1.6 ventilation volume of 50% porosity of soil, and no ventilation) under conditions of the different soil moisture upper limits. The effects of different rhizosphere soil aerations on the physiological indicators and water absorption of tomato were studied. Under the same soil moisture condition, plant growth and root vitality initially increased, and then decreased when the soil ventilation volume increased. The combination of soil moisture with 80% of field capacity and 0.8 ventilation volume with 50% soil porosity raised the chlorophyll content by 29.98% and the root vitality by 61.55%, as compared with the non‐ventilated treatment. Therefore, the appropriate volume of rhizosphere ventilation can effectively improve the capacity of water absorption in tomato. The result provides a new view about soil quality and soil ecology in terms of soil–root system. 相似文献
383.
西准噶尔地区广泛分布的和布克河组已被证明是洪古勒楞组的晚出异名,本文在西准噶尔克拉赛勒克山原划为下石炭统"和布克河组"的碎屑岩地层中发现了丰富的动、植物化石,包括:三叶虫Phacops sp.,菊石Manticoceras sp.,腕足类Tylothyris sp.,Aulacella sp.,"Mucrospirifer"sp.,Cyrtospirifer sp.,植物Leptophloeum rhombicum,Syringodendron sp.,Knorria sp.,其时代显示为晚泥盆世。根据岩性组合特征将其厘定为上泥盆统铁列克提组,而非"和布克河组"的替代名称洪古勒楞组。通过区域地质调查工作,证明了西准噶尔玛依力山地层小区内没有洪古勒楞组的分布,其晚泥盆世地层仅由铁列克提组组成,洪古勒楞组只分布在沙尔布尔提山地层小区,两个地层小区的界线为孟布拉克北侧至谢米斯台山南坡的深大断裂。晚泥盆世两个地层小区沉积分异明显,直到早石炭世早期才进入统一的盆地演化阶段,地层小区的分区性也随之消失。 相似文献
384.
Hou Kangming Zong Kaihong Guo Jiangning Xiong Zhen Li Limei Zhou Caixia Jiang Bo 《中国地震研究》2009,23(1):78-86
The Changjiang fault zone, also known as the Mufushan-Jiaoshan fault, is a famous fault located at the southern bank of the Changjiang River, near the Nanjing downtown area. Based on multidisciplinary data from shallow artificial seismic explorations in the target detecting area (Nanjing city and the nearby areas), trenching and drilling explorations, classification of Quaternary strata and chronology dating data, this paper provides the most up-to-date results regarding activities of the Changjiang fault zone, including the most recent active time, activity nature, related active parameters, and their relation to seismic activity. 相似文献
385.
对非径向脉动δScuti(盾牌座δ)型变星4CVn的最新光电测光观测,证实了其振幅和周期的长期缓慢变化.两种多重频率分析方法都一致确认出已知7个频率中的5个(f1,f2,f3,f5,f7).观测还发现三个可疑频率.目前主频的振幅和十几年前的一样,基本保持不变,可能正处于向最大振幅变化的增加阶段或者处于刚过极大的下降段.其它四个频率的振幅都不同程度地变大.f2,f3和f5的振幅增幅分别为63%,25%和120%,尤其是f7,从上次的0变为0.009mag.频率分析显示除主频f1几乎未变外,其它频率缓慢变化:f2和f7约减小0.08%;f3减小0.14%;f5增加0.03%.用Blazhko效应和不同非径向脉动模式之间的共振解释振幅和周期变化的合理性,尚需进一步从观测上检验. 相似文献
386.
Q. G. Zong T. A. Fritz A. Korth P. W. Daly M. Dunlop A. Balogh J. F. Fennell J. D. Sullivan R. W. H. Friedel H. Reme 《Surveys in Geophysics》2005,26(1-3):215-240
Energetic electrons (e.g., 50 keV) travel along field lines with a high speed of around 20 REs−1. These swift electrons trace out field lines in the magnetosphere in a rather short time, and therefore can provide nearly instantaneous information about the changes in the field configuration in regions of geospace. The energetic electrons in the high latitude boundary regions (including the cusp) have been examined in detail by using Cluster/RAPID data for four consecutive high latitude/cusp crossings between 16 March and 19 March 2001. Energetic electrons with high and stable fluxes were observed in the time interval when the IMF had a predominately positive Bz component. These electrons appeared to be associated with a lower plasma density exhibiting no obvious tailward plasma flow (<20 keV). On the other hand, no electrons or only spike-like electron events have been observed in the cusp region during southward IMF. At that time, the plasma density was as high as that in the magnetosheath and was associated with a clear tailward flow. The fact that no stable energetic electron fluxes were observed during southward IMF indicates that the cusp has an open field line geometry. The observations indicate that both the South and North high latitude magnetospheric boundary regions (including both North and South cusp) can be energetic particle trapping regions. The energetic electron observations provide new ways to investigate the dynamic cusp processes. Finally, trajectory tracing of test particles has been performed using the Tsyganenko 96 model; this demonstrates that energetic particles (both ions and electrons) may be indeed trapped in the high latitude magnetosphere. 相似文献
387.
陕西大茅坪铜矿床赋存于中元古代碧口群火山岩中,是陕西勉略宁三角区西部较典型的铜矿之一,对该矿床的研究有助于有效地指导在本区寻找同类型矿床。文中对原生晕分析数据,物探测量数据进行了不同方法的处理,在此基础上提出了综合找矿模型。其中对原生晕,通过不同方法建立了地球化学背景与异常的概率筛分模型,因子分析及元素组合模型、标准化丰度法及轴向分带模型;对物探数据进行线性加权组合建立了综合物探异常并运用该模型进行了初步预测。 相似文献
388.
为建立山东省临沂市沂蒙山区特殊地质背景土壤质量评价方法,在沂南县西南部研究区采集各类土壤样品1 029件,均分析了N、P、K、Mn、B、Mo、Cu、Zn、Co、V、Ni、Sr、Tl、Ti、As、Cd、Hg、Pb、Cr、Se、F、I、Ge、有机质、Na2O、SiO2、MgO、CaO质量分数及pH等29项指标。根据分析测试结果,建立了由土壤养分指标和环境指标组成的评价体系,并对该区土壤质量地球化学评价及其空间分布进行了研究。结果表明:研究区大部分土壤质量以良好、中等为主(土壤环境清洁,土壤养分丰富或中等);研究区中部地区土壤肥力较好(w(N)>0.10%,w(P)>0.06%,w(K)>2.50%),西南部、东北部山区土壤肥力较差(w(N)<0.075%),土壤质量等级偏低。全区80%左右土壤的N元素、B元素、有机质均不足以满足常规农业生产需要,对常规作物生长不利。区内土壤环境质量水平总体较好,重金属元素分布受地质背景控制。 相似文献
390.
为获得高效好氧反硝化细菌,并研究这些细菌的脱氮特性以及好氧反硝化机理,采集了近海表层沉积物进行富集培养,分离获得一株具有高效好氧反硝化能力的菌株F13-1.结合生理生化特征及16S rRNA基因序列分析,初步鉴定菌株F13-1为卓贝尔氏菌(Zobellella sp.).在以葡萄糖为碳源,C/N比值为15,盐度为30,摇床转速160 r/min,p H值为7,28℃的最优脱氮条件下菌株F13-1脱氮效果较好,分别能将100 mg/dm3硝酸盐和亚硝酸盐在24和16 h内彻底脱除,脱除速率分别为:5.87 mg/(dm3·h)和5.97 mg/(dm3·h).并且菌株F13-1对高浓度亚硝酸盐具有较好的耐受性,能在高浓度亚硝酸盐存在条件下正常生长及脱氮,156 h内能将400 mg/dm3亚硝酸盐脱除完全.基因组分析表明,该菌株具有完整的反硝化基因簇,包括nap、nir、nor和nos等共17个基因.研究结果表明该菌株具有高效好氧反硝化特性,在养殖废水处理中具有较好的应用潜力. 相似文献