耦合气溶胶气候模式FGOALS-f3-L模拟青藏高原地区气溶胶特性

基于新耦合气溶胶气候模式FGOALS-f3-L模拟分析了2002-2011年青藏高原地区气溶胶时空分布特征.结果表明:青藏高原地区,沙尘,硫酸盐,碳质气溶胶(包括黑碳,有机碳和混合碳)地表质量浓度分别占比为53.6％,32.2％,14.2％;在拉萨站点,模拟的气溶胶地表质量浓度被低估,尤其是黑碳和有机碳气溶胶;模拟的气...     

A Dynamic Network with Individual Mobility for Designing Vaccination Strategies

Vaccination is a primary means to control infectious diseases. Few studies on vaccination strategies have explicitly considered the mobility of individuals. This article aims to evaluate the efficacy of three vaccination strategies in a dynamic social network, in which individuals are mobile between and within communities. The three vaccination strategies are applied to this social network for evaluation, including a travel‐based, a contact‐based, and a random vaccination strategy. Simulation results show that the contact‐based strategy, commonly seen in previous studies, is not always the most effective strategy in dynamic networks. This strategy is preferable for a population with a large number of intercommunity travelers, for instance in urban areas. On the other hand, the travel‐based strategy, although directly accounting for individual mobility, is not necessarily the most effective in dynamic networks either. This strategy is recommended for a population with a small number of intercommunity travelers, such as rural areas. In addition, one advantage of the travel‐based strategy over the other two is its efficacy in confining the spatial extent of affected areas. Results suggest that the intercommunity travel of individuals should be a major consideration for choosing proper vaccination strategies. By adding the spatial context into vaccination strategies, this research provides new insights into community‐based planning for infectious disease control.     

大兴安岭中段晚二叠世林西组介形虫化石及环境意义

晚二叠世-中三叠世在中亚造山带东段构造演化过程中是承上启下的关键地质时期,所以晚二叠世林西组沉积环境对研究古亚洲洋闭合这一重大问题具有重要意义。大兴安岭地区晚二叠世林西组曾有双壳、叶肢介、植物及孢粉化石记录,但鲜有介形虫化石报道。在大兴安岭中段林西组研究中首次发现介形虫化石,经初步研究,主要分子有Kemeroviana,Volganella,Iniella,Qitaina,Darwinuloides,Palaeocypridopsis,Tomiella,Darwinula和Urumqiella等,暂划为Volganella-Kemeroviana组合,其时代为晚二叠世。与俄罗斯地台晚二叠世介形虫化石群关系较为密切,部分属种曾见于我国新疆准噶尔盆地和塔里木盆地。从介形虫化石组合特征和保存特点来看,其生存环境为淡水湖泊,故认为这一地区的林西组为陆相沉积。     

盘谷寺-新乡断裂倾向反转成因探讨

盘谷寺-新乡断裂在大高村附近断层倾向发生反转,大高村以西倾向为南,大高村以东倾向为北。为查明倾向反转成因,跨断层布设3条浅层地震测线,通过采用高分辨率地震数据及高精度数据处理技术,获得清晰的地下结构与构造成像。结果显示,武陟隆起北侧边缘发育有隐伏隆起,该隆起的发育使得盘谷寺-新乡断裂大高村以西段在L1测线与L2测线之间消失,同时向南倾的武陟断裂演变为济源凹陷的边界断裂,自西向东该隆起规模逐渐增大。该隆起北侧边缘开始发育北盘谷寺-新乡断裂大高村以东段,南侧边缘开始发育向南倾的平陵断裂,且随隆起规模的继续增大,盘谷寺-新乡断裂大高村以东段及平陵断裂自西向东活动性逐渐增强。推测该隐伏隆起是引起该区盘谷寺-新乡断裂倾向反转的主要成因。     

Density Perturbation and Energy Flux of Internal Waves from Velocity Data

Internal waves play a crucial role in ocean mixing, and density perturbation and energy flux are essential quantities to investigate the generation and propagation of internal waves. This paper presents a methodology for calculating density perturbation and energy flux of internal waves only using a velocity field that is based on linearized equations for internal waves. The method was tested by numerical simulations of internal waves generated by tidal flowing over a Gaussian topography in a stratified fluid. The density perturbations and energy fluxes determined using our method that only used velocity data agreed with density perturbations and energy fluxes determined by the equation of state based on temperature data. The mean relative error (MRE) and root mean square error (RMSE) between the two methods were lower than 5% and 10% respectively. In addition, an experiment was performed to exam our method using the velocity field measured by Particle Image Velocimetry (PIV), and the setup of the experiment is consistent with the numerical model. The results of the experiments calculated by the methods using PIV data were also generally equal to those of the numerical model.     

Pulse phase-resolved analysis of SMC X-3 during its 2016–2017 super-Eddington outburst

The Be X-ray pulsar SMC X-3 underwent an extra long and ultraluminous giant outburst from 2016 August to 2017 March. The peak X-ray luminosity is up to \(\sim10^{39}~\mbox{erg/s}\), suggesting a mildly super-Eddington accretion onto the strongly magnetized neutron star. It therefore bridges the gap between the Galactic Be/X-ray binaries (\(L_{\mathrm{X}}^{\mathrm{peak}} \leq10^{38}~\mbox{erg/s}\)) and the ultraluminous X-ray pulsars (\(L_{\mathrm{X}}^{\mathrm{peak}} \geq10^{40}~\mbox{erg/s}\)) found in nearby galaxies. A number of observations were carried out to observe the outburst. In this paper, we perform a comprehensive phase-resolved analysis on the high quality data obtained with the Nustar and XMM-Newton, which were observed at a high and intermediate luminosity levels. In order to get a better understanding on the evolution of the whole extreme burst, we take the Swift results at the low luminosity state into account as well. At the early stage of outburst, the source shows a double-peak pulse profile, the second main peak approaches the first one and merges into the single peak at the low luminosity. The second main peak vanishes beyond 20 keV, and its radiation becomes much softer than that of the first main peak. The line widths of fluorescent iron line vary dramatically with phases, indicating a complicated geometry of accretion flows. In contrast to the case at low luminosity, the pulse fraction increases with the photon energy. The significant small pulse fraction detected below 1 keV can be interpreted as the existence of an additional thermal component located at far away from the central neutron star.     

飞秒啁啾Gauss型脉冲在稠密Λ型三能级原子介质中的传播

利用由预估校正(PC)- 时域有限差分(FDTD)法求得的不含慢变包络近似(SVEA)和旋转波近似(RWA)的全波Maxwell-Bloch方程的数值解, 研究了飞秒啁啾Gauss型激光脉冲(以下简称啁啾脉冲)在稠密Λ型三能级原子介质中的传播.研究表明,啁啾系数(C)的正负及大小的变化对脉冲传播特性有显著的影响,而且这个影响与脉冲面积的大小密切相关.面积小于4π的啁啾脉冲,在介质中传播时不发生分裂,且啁啾脉冲逐渐演化为一个近似的无啁啾(C=0)脉冲,这一特点不随啁啾系数的改变而     

用地震反射剖面研究汤阴地堑上地壳结构与断裂特征

汤阴地堑位于太行山脉与华北平原的过渡带,是太行山前重要的地质构造单元。为研究汤阴地堑上地壳结构和断裂特征,利用安阳市与新乡市活断层探测获得的深、浅地震反射剖面,结合研究区已有地震、地质资料,对汤阴地堑浅部结构、汤东断裂特征进行分析研究。结果表明,汤阴地堑北部与南部地壳结构差异明显。地堑北部是由汤东断裂控制的半地堑,地堑内反射震相丰富、反射波层组关系清晰,多组新生代、古生代沉积层强反射不整合地覆盖在自西向东倾伏的结晶基底反射T_g上,且随着深度增加,地层倾角增大,显示出明显的多期掀斜运动特征。地堑南部表现为由汤东、汤西断裂共同控制的断陷型地堑,地堑内新近系底界面反射波TN自西向东倾伏,其下为一些横向呈水平或东倾、延续性较短的反射震相。地堑南部与北部不同的反射震相特征表明,测线控制区域内的汤阴地堑沉积环境与运动特征可能有所差异。汤东断裂为走向NE,倾向NW的铲型正断层,汤西断裂为走向NE、倾向SE的正断层,北部中深层地震反射剖面上未发现该断层的存在。     

藏北羌塘中侏罗世沟鞭藻

在藏北羌塘盆地中生界烃源岩成烃母质研究的一块标本中 ,发现了丰富且保存良好的沟鞭藻化石 ,至少包括有 2 1个属、 3 2个种的组合。这个组合以旋沟藻型占统治 ,大量发育栉型孢囊 ( ctenidodinioid) ,尤以 Ctenidodinium combazii居首位 ,其次为 Ellipsoidictyum cinctum和L ithodinia 的种 ,还有 Ctenidodinium continuum,C.ornatum,Gongaulacysta jurassica,Systematophora penicillata,Tubotuberella dangeardii和 Valensiella ampulla等中侏罗世巴统期至卡洛期的常见分子参与。根据组合面貌和属种成分的已知地史分布 ,其时代可确定为巴统期( Bathonian)或可能延至早卡洛期 ( Callovian)。沉积环境为正常盐度的开阔海 ,与欧洲诸海域可以沟通。本文还对 3个重要种进行了系统描述     

Predictive GIS model for potential mapping of Cu, Pb, Zn mineralization

IntroductionChina is the third richest country in the world ofmineral resources with a total potential value of 11trillion USdollars. Yunnan Provincce is one of theimportant metallogenic belts for nonferrous and pre-cious metal deposits[1].Mineral source …