川中大安寨段风暴沉积特征及分布模式     

冯荣昌  吴因业  杨光  杨家静  刘敏  张天舒  岳婷 《沉积学报》2015,33(5):909-918

风暴沉积在川中大安寨段比较发育,对大安寨段风暴沉积的沉积构造特征进行研究,发现大安寨段风暴沉积虽然缺乏丘状交错层理,但顶底面构造和层理构造比较发育。综合分析顶底面构造和层理构造特征,总结了大安寨段风暴沉积的理想沉积相序结构,即一个完整的风暴层序从下向上发育:渠模或侵蚀面、砾屑层、粒序层理、波状层理、漂浮介屑段、粉砂屑层和截切或波痕。由于各微相的水动力条件的差异导致风暴沉积层序在各微相中保存的程度不同,在能量较高的滩前、滩核、滩后主要以粒序层为主,滨浅湖主要以粉砂屑层理为主,半深湖发育漂浮状介屑层、波状层理、粉砂屑层理。风暴沉积的研究加深了对大安寨段半深湖灰岩成因的认识,滩前和半深湖相的风暴成因的灰岩的孔隙度相对较好,具有较好的烃源与保存条件,是致密油勘探的有利相带。  相似文献   

基于双参数模型核脉冲信号数字高斯成形技术     

周伟  周建斌 《物探与化探》2015,(2):318-321

阐述了一种基于脉宽和幅度双参数的新型核脉冲信号数字高斯成形模型的研究方法。以Sallen-Key滤波器(以下简称S-K滤波器)为基础,运用基尔霍夫电流定律建立输入信号Vi和输出信号Vo之间的数学关系方程。方程解算过程中,引入脉宽和幅度双因子进行参数替代,并运用数值微分算法迭代得到一个核脉冲信号数字高斯成形的数值递推模型。通过标准指数衰减信号和实际核信号仿真验证了该模型的正确性,也进行了成形参数的确定。最后,实测55Fe核素标准谱线的结果显示在能量色散X荧光分析系统中应用数字高斯成形技术,提升了系统能量分辨率和计数通过率等性能指标,收到了良好效果。  相似文献   

活动星系核中的准周期振荡现象     

李根源  王仲翔 《天文学进展》2023,(2):169-180

近年来,在活动星系核的光变曲线中越来越多的准周期振荡现象被发现并报道,而对此类现象的研究很有可能成为一种探索超大质量黑洞物理机制的特殊且有效的手段。首次收集了报道出的准周期振荡事例,并对其分不同波段进行了整理;此外还介绍了不同波段上显著事例的特点并阐明其相关的物理过程。根据所搜集的事例,讨论了它们的整体特点,其中所探测的周期具有很强的观测选择效应,并且至今高可信度的事例不多。目前考虑的准周期振荡的产生机制都与Lense-Thirring效应或双黑洞系统有关。相信在不久的将来,随着各类大型巡天项目的开展,会有大量的活动星系核准周期振荡现象被发现,这将有助于对该现象的深入研究。  相似文献   

Mean Flow–Storm Track Relationship and Rossby Wave Breaking in Two Types of El-Nino简   总被引：1，自引：0，他引：1  

LIU Chengji  REN Xuejuan  YANG Xiuqun 《大气科学进展》2014,31(1):197-210

The features of large-scale circulation, storm tracks and the dynamical relationship between them were examined by investigating Rossby wave breaking （RWB） processes associated with Eastern Pacific （EP） and Central Pacific （CP） E1-Nifio. During EP E1-Nino, the geopotential height anomaly at 500 hPa （Z500） exhibits a Pacific-North America （PNA） pattern. During CP EI-Nifio, the Z500 anomaly shows a north positive-south negative pattern over the North Pacific. The anomalous distributions of baroclinicity and storm track are consistent with those of upper-level zonal wind for both EP and CP EI-Nino, suggesting impacts of mean flow on storm track variability. Anticyclonic wave breaking （AWB） oczurs less frequently in EP EI-Nino years, while cyclonic wave breaking （CWB） occurs more frequently in CP EI-Nino years over the North Pacific sector. Outside the North Pacific, more CWB events occur over North America during EP Ei-NiNo. When AWB events occur less frequently over the North Pacific during EP EI-Nino, Z500 decreases locally and the zonal wind is strengthened （weakened） to the south （north）. This is because AWB events reflect a monopoie high anomaly at the centroid of breaking events. When CWB events occur more frequently over the North Pacific under CP EI-Nino conditions, and over North America under EP EI-Nino condition, Z500 increases （decreases） to the northeast （southwest）, since CWB events are related to a northeast-southwest dipole Z500 anomaly. The anomalous RWB events act to invigorate and reinforce the circulation anomalies over the North Pacific-North America region linked with the two types of EI-Nino.  相似文献   

Assimilation of Doppler Radar Observations with an Ensemble Square Root Filter：A Squall Line Case Study          下载免费PDF全文

QIN Yanyan  GONG Jiandong  LI Zechun  SHENG Rifeng 《Acta Meteorologica Sinica》2014,28(2):230-251

The effectiveness of using an Ensemble Square Root Filter（EnSRF） to assimilate real Doppler radar observations on convective scale is investigated by applying the technique to a case of squall line on 12July 2005 in midwest Shandong Province using the Weather Research and Forecasting（WRF） model.The experimental results show that：（1） The EnSRF system has the potential to initiate a squall line accurately by assimilation of real Doppler radar data.The convective-scale information has been added into the WRF model through radar data assimilation and thus the analyzed fields are improved noticeably.The model spin-up time has been shortened,and the precipitation forecast is improved accordingly.（2） Compared with the control run,the deterministic forecast initiated with the ensemble mean analysis of EnSRF produces more accurate prediction of microphysical fields.The predicted wind and thermal fields are reasonable and in accordance with the characteristics of convective storms.（3） The propagation direction of the squall line from the ensemble mean analysis is consistent with that of the observation,but the propagation speed is larger than the observed.The effective forecast period for this squall line is about 5-6 h,probably because of the nonlinear development of the convective storm.  相似文献   

基于高低潮的风暴增水人工神经网络预报模型     

王如云  雷磊  占飞  周钧 《海洋预报》2014,31(6)

针对只有高低潮数据的情况,利用人工神经网络建立起一种预报当前台风时刻后第一个高潮时增水的模型。该模型选取台风在当前时刻、前6 h、前12 h、前18 h的中心经度、纬度、最大风速、中心气压以及当前时刻前第一个高潮时刻的风暴增水为输入单元。台风当前时刻后第一个高潮时刻风暴增水为模型输出单元。利用历史资料形成的规范化后的模式对,对模型进行训练,训练成功后,结合台风因子预报模型,即可用于风暴增水的预报。经过长江口高桥站高低潮实测资料的检验,结果表明该模型提取到了风暴增水效应,说明该模型可用于风暴增水的预报。  相似文献   

Characterization of ribulose-1, 5-bisphosphate carboxylase/oxygenase and transcriptional analysis of its related genes in Saccharina japonica (Laminariales,Phaeophyta)     

邵展茹  刘福利  李秋莹  姚建亭  段德麟 《中国海洋湖沼学报》2014,32(2):377-389

Saccharina japonica is a common macroalga in sublittoral communities of cold seawater environments,and consequently may have highly effi cient ribulose-1,5-bisphosphate carboxylase/oxygenase(Rubisco)activity for carbon assimilation.In our study,we cloned the full-length Rubisco gene from S.japonica(SJ-rbc).It contained an open reading frame for a large subunit gene(SJ-rbcL)of 1 467 bp,a small subunit gene(SJ-rbcS)of 420 bp,and a SJ-rbcL /S intergenic spacer of 269 bp.The deduced peptides of SJ-rbcL and SJ-rbcS were 488 and 139 amino acids with theoretical molecular weights and isoelectric points of 53.97 kDa,5.81 and 15.84 kDa,4.71,respectively.After induction with 1 mmol/L isopropyl-β-Dthiogalactopyranoside for 5 h and purifi cation by Ni 2+ affi nity chromatography,electrophoresis and western blot detection demonstrated successful expression of the 55 kDa SJ-rbcL protein.Real-time quantitative PCR showed that the mRNA levels of SJ-rbcL in gametophytes increased when transferred into normal growth conditions and exhibited diurnal variations: increased expression during the day but suppressed expression at night.This observation implied that Rubisco played a role in normal gametophytic growth and development.In juvenile sporophytes,mRNA levels of SJ-rbcL,carbonic anhydrase,Calvin-BensonBassham cycle-related enzyme,and chloroplast light-harvesting protein were remarkably increased under continuous light irradiance.Similarly,expression of these genes was up-regulated under blue light irradiance at 350 μmol/(m 2·s).Our results indicate that long-term white light and short-term blue light irradiance enhances juvenile sporophytic growth by synergistic effects of various photosynthetic elements.  相似文献   

砥砺前行 筑梦辉煌——青海省核工业地质局建局15周年回顾     

赵世勇 《青海国土经略》2014,(3):24-27

正光阴似箭,岁月峥嵘。核工业系统推行属地化改革已整整十五年了,而当时的核工业西北地质局652大队,从被属地化归到地方、建局到现在也已经走过了十五年的岁月。回首往昔,自属地化以来,青海省核工业地质局从直面艰难、挑战到逐步融入地方,从寻找机遇、探寻出路到定准发展方向,从艰苦奋斗到取得成绩、实现辉煌,走过了一条不同寻常的道路。一路走来,作为亲历者、带领全  相似文献   

小秦岭地质公园迎来首个旅游专列     

陈海 《河南国土资源》2014,(7):26-26

正5月25日,"娘娘山号"高铁专列在灵宝西站徐徐停下,700余名游客来到了"中国金城"——灵宝市。这是小秦岭国家级地质公园开园以来,迎来的首个旅游专列。"娘娘山号"高铁旅游专列由灵宝市人民政府和洛阳铁鑫等多家旅行社联合组织实施,是灵宝市大旅游战略的一次重要行动。当日13时,700余名游客乘坐10余辆旅游大巴到达小秦岭地质公园娘娘山景区,开始了娘  相似文献   

奇异的海底“风暴”     

骆昌芹 《气象知识》2014,(1):68-69

人类的足迹,已踏遍千山万水。然而,占地球3／4的辽阔海洋仍留下许多伞空白点,尤其是海底深处的一片片“处女地”,正期待着我们去探索,去开发,解开其中的疑谜。  相似文献