长江三角洲地区人体舒适度时空变化特征北大核心CSCD

基于1981~2020年ERA5逐小时再分析资料,采用通用热气候指数(Universal Thermal Climate Index,UTCI)计算方法,分析了气候变化背景下长江三角洲地区人体生理热响时空变化特征。研究表明:近40年长江三角洲地区人体无冷热胁迫气候条件的出现频率约为43.77%、热胁迫和冷胁迫出现频率分别约为22.42%和33.81%,其中,显著热胁迫和显著冷胁迫出现频率分别约为8.38%和1.58%;在空间分布上,长江三角洲地区无冷热胁迫气候条件的出现频率总体表现为南多北少地带性分布,兼有山区多平原少、沿海多内陆少分布特征,显著热胁迫主要出现在皖西和皖南的平原以及浙江的嘉绍平原和金衢盆地,显著冷胁迫主要出现在苏北、皖北和舟山以北的沿海岸区;在全球气候变暖背景下,长江三角洲地区UTCI值的年代际变化呈上升趋势,由1981~1990年13.83℃增加至2011~2020年14.75℃,人体生理热响应表征为冷胁迫减少、热胁迫增加、无冷热胁迫基本不变,春季无冷热胁迫时长的增加基本抵消了夏季无冷热胁迫时长的减少。     

基于ESPRIT算法的极化干涉SAR植被高度反演研究

由于存在着去相干分量,利用ESPRIT(旋转不变技术)算法对植被区域的极化干涉SAR(PollnSAR)数据进行反演的结果有较严重偏差.针对这一问题,结合极化干涉相干最优理论及其物理散射机制,引入新的散射矢量——相干最优化散射矢量,提出一种改进的基于ESPRIT的植被高度反算法.最后,利用欧空局(ESA)提供的模拟L波...     

Ionospheric response to the geomagnetic storm on 13–17 April 2006 in the West Pacific region

This paper presents an investigation of geomagnetic storm effects in the equatorial and middle-low latitude F-region in the West Pacific sector during the intense geomagnetic storm on 13–17 April, 2006. The event, preceded by a minor storm, started at 2130 UT on April 13 while interplanetary magnetic field (IMF) B_z component was ready to turn southward. From 14–17 the ionosphere was characterized by a large scale enhancement in critical frequency, foF2 (4～6 MHz) and total electron content (TEC) (～30TECU, 1TECU=1×10¹⁶el/m²) followed by a long-duration negative phase observed through the simultaneous ionospheric sounding measurements from 14 stations and GPS network along the meridian 120°E. A periodic wave structure, known as traveling ionospheric disturbances (TIDs) was observed in the morning sector during the initial phase of the storm which should be associated with the impulsive magnetospheric energy injection to the auroral. In the afternoon and nighttime, the positive phase should be caused by the combination of equatorward winds and disturbed electric fields verified through the equatorial F-layer peak height variation and modeled upward drift of Fejer and Scherliess [1997. Empirical models of storm time equatorial electric fields. Journal of Geophysical Research 102, 24,047–24,056]. It is shown that the large positive storm effect was more pronounced in the Southern Hemisphere during the morning-noon sector on April 15 and negative phase reached to lower magnetic latitudes in the Northern Hemisphere which may be related to the asymmetry of the thermospheric condition during the storm.     

霍洛湾煤矿22101工作面顶板两带发育规律

在详细分析霍洛湾煤矿水文地质条件基础上,根据2-2煤层上覆不同岩层的岩石力学参数建立了工作面回采过程中覆岩变形与破坏特征的数值模拟模型,研究了工作面回采过程中顶板覆岩在不同来压阶段导水裂隙带和垮落带的发育高度;通过对钻孔冲洗液漏失量的现场观测,进行了“两带”发育高度的探测。将数值模拟结果及现场观测资料对比分析,确定22101工作面的导水裂隙带高度为33.6~37.8m,垮落带高度约9.6m。这为评价研究区水体下开采可行性和水体下开采防水煤柱的设计提供了科学依据。      

QBO Signal in total ozone over Tibet

1. IntroductionOzone is one of the trace gases in the atmosphere distributed in 10--50 km altitude withthe maximum in 20--28 km. Ozone is significant in the following three aspects impacting theclimate and environment: 1) Ozone absorbs harmful solar ultra--violet radiation for protecting the ecological system on the Earth; 2) ozone heats the stratosphere and forces the circulation systems in this layer; 3) ozone variation in the stratosphere can change the incomingradiation at the surface leve…     

Comparative Planetary Space Physics

It has been 60 years since the space physics as new branch of geophysics started to grow in 1957 when the space age was opened by a small satellite called sputnik. The knowledge of Earth and planetary space has been significantly extended and deepened, but the questions we are facing today are more challenging. A consensus reached is that we have to regard the Earth (planet) as an integrated system including all spheres from the inner core to the magnetosphere, and we should try to investigate some questions standing on the ground of interdisciplinary study, especially those questions related to Earth’s (planetary) evolution. Space environment as the outer part of a planetary system, commonly exists in all planets but also exhibits strong diversity. Here, we introduce the short history of basic ideas and methods of comparative study, the advantages on understanding of some issues of global scale, and the prospect from comparative perspective.     

中国东部四明山古夷平面遗迹特征与演化

古夷平面研究在地貌演化和新构造运动研究中占有极其重要的地位,但由于遭受构造运动和剥蚀作用的影响,很多古夷平面遗迹已无从清晰辨识。浙江四明山顶古近纪夷平古风化壳面的发现,为研究浙江东部甚至华东地区的新生代地貌演化提供了重要地质信息,同时为始新世和中新世时的古气候、古环境研究提供了重要物质证据。通过详细的野外地质调查,系统采集了该区5个点位的20个古风化壳样品和7个点位的15个现代风化壳样品,开展黏土矿物分析和玄武岩K-Ar年龄测试。研究确认四明山地区发育有2期古夷平面遗迹,即古近纪(E)和新近纪(N)古夷平面遗迹:第一期夷平面发育时间为65. 0～32. 2 Ma,解体和古夷平面遗迹保存时间为32. 2～21. 7 Ma;第二期夷平面发育时间为21. 7～10. 5 Ma,解体和古夷平面遗迹保存时间为10. 5～3. 0 Ma。研究区2期火山活动喷发所形成的玄武岩盖层有效保护了该区的古风化壳,从而使四明山古夷平面遗迹具有空间展布完整、剖面信息清晰等特征,呈现出由古夷平面(古风化壳)与玄武岩堆积面(现代风化壳)组成的"双风化壳"现象,为观察古夷平面遗迹特征提供了最佳场所。     

赞比亚北部班韦乌卢地块演化及矿产资源研究现状

赞比亚北部班韦乌卢地块受到古元古代乌本迪构造带、新元古代基巴拉构造带、新元古代伊鲁米德构造带及泛非期卢弗里安构造带的影响,主要分布有金、锰和金刚石矿床(点)。金矿床(点)主要赋存于姆波罗科索盆地东部姆巴拉组以紫红色砾岩—砂岩为主的碎屑沉积岩中,并且有较好的矿化线索。锰矿床主要分布在曼萨周围,可分为沉积型和构造型两类。班韦乌卢地块东部边缘发育含金刚石的钾镁煌斑岩和金伯利岩,在伊索卡地区前人利用重砂方法找到金刚石,推测地块内部可能寻找到含金刚石的钾镁煌斑岩和金伯利岩。因此,作者通过研究班韦乌卢地块的演化及其矿产资源现状,认为该地区具有较好的找矿潜力,可为中资矿业企业的矿权登记及矿产开发等方面提供基础的地质资料和科学依据,符合国家实施的矿产资源勘查开发"走出去"战略和"一带一路"战略。     

Sea water environment copper requirement of egg hatching and naupliar metamorphosis of Peaneus chinensis

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辽东凤凰山正长花岗岩SHRIMP U-Pb年龄、地球化学特征与陆内伸展作用

【研究目的】 辽宁丹东地区发育着一期A型花岗岩,因其特殊的成因演化,特定的构造背景及其重要的地球动力学意义而备受关注。【研究方法】 本文通过对辽宁丹东凤凰山岩体SHRIMP锆石U-Pb年代学、岩石地球化学特征的分析,探讨了该岩体形成时代、岩石成因及地球动力学背景。【研究结果】 辽东凤凰山黑云母正长花岗岩锆石U-Pb年龄分别为（122.3±1.7）Ma、（125.0±1.7）Ma、 （122±2）Ma,代表岩浆结晶年龄,凤凰山正长花岗岩侵位时代属于早白垩世。地球化学分析结果显示,SiO₂含量为65.65%～73.62%,K₂O为3.52%～5.76%,Na₂O为3.64%～4.26%,Al₂O₃为13.4%～15.49%,A/CNK值1.02～1.46,属铝过饱和型。碱度率AR在2.71～5.13,基本在铝质A型花岗岩AR值范围内,FeO_t/MgO比值为4.69～18.05,表现为A型花岗岩的A1和A2过渡类型。Rb/Nb比值为6.02～8.64,明显高于大陆壳的Rb/Nb比值2.2～4.7,说明陆壳物质对岩体成岩影响较大,从而导致Rb的含量增加。相对富集大离子亲石元素Rb、Th, Zr、Hf,亏损Sr、P、Ba、Ti、Nb。稀土总量较高,轻重稀土之间的分馏不明显,Eu具明显的负异常。【结论】 综上,凤凰山正长花岗岩可能产生于陆内剪切相关的伸展环境,应为自中侏罗世开始由板块俯冲引起的东亚大陆边缘构造过程的响应。