A model oscillator of irregular stellar variability     

Y. Tanaka  M. Takeuti 《Astrophysics and Space Science》1988,148(2):229-237

We have studied a set of equations with nonlinear and nonadiabatic terms which describes a simple oscillator. The equations have only one fixed point located at the origin. It is found that the oscillator shows the sequence of the period-doubling for the change of a parameter and results in chaotic oscillation. We illustrated the behaviour of the oscillator for several set of parameters and showed that the equations of the oscillator can be reduced to the one-zone model of stellar pulsation with simple nonlinear terms. It is suggested that the stellar irregular variability is resulted from the chaotic motion due to the nonlinear effect.  相似文献   

The coupling coefficients of radial pulsation in third order     

T. Ishida  R. Takano  F. Yamakawa  M. Takeuti 《Astrophysics and Space Science》1993,210(1-2):349-349

The third order theory of coupling is discussed regarding the radial pulsation of stellar models.  相似文献   

太白双王含金水压角砾岩体形成过程和金矿体预测   总被引：8，自引：0，他引：8       下载免费PDF全文

汪劲草  汤静如等 《地质论评》2001,47(5):508-513

陕西双王含金角砾岩体为水压角砾岩体，是深源富碱含金流体使泥盆系一套热水沉积的富钠质岩系发生水力压裂作用形成的。早期共轴递进挤压使能干性富钠质岩系与非能干性富泥质岩系发生变形分离，分别形成近等距分布的透镜状弱变形域与线性强变形带，其中，弱变形域中央是一个相对低温，低压，高渗透率的透镜状天然泵吸中心；晚期的右旋高角度斜冲非共轴递进剪切使弱变形域中央最发育的一组节理和裂隙由压性转变为张性，并沟通溶 部的裂隙系统，泵吸中心巨大的压力降使深部的承压流体在富钠质岩系中产生周期性的构造泵吸一水力压裂－沉淀愈合作用，根据分解变形构造型式预测的隐伏含金水压角砾岩体已获钻探初步验证。  相似文献   

A Candidate Global Stratotype Section and Point for the Precambrian——Cambrian Boundary at Meishucun,Yunnan,China     

Xing Yusheng The Geological Museum of China  Beijing Luo Huilin Jiang Zhiwen Yunnan Institute of Geological Sciences  Kunming  Yunnan Zhang Shishan Kunyang Phosphorite Mine  Jinning  Yunnan 《中国地质大学学报(英文版)》1991,(1)

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保和堂矿区龙潭组下三角洲平原聚煤特征     

莫时旭  许桂生 《湖南地质》1997,16(4):227-231

邵东保和堂矿区龙潭组１，２煤形成地下三角洲平原废弃期，３煤形成于三角洲建设期，前者聚煤条件较好。在三角洲废弃破坏期，潮汐水流对形成于三角洲平原的煤层有较强的发行作用。本文提出了潮汐对煤厚，煤质及煤岩组成的作用机制。  相似文献   

新化古台山金锑矿床蚀变特征及其找矿方向   总被引：3，自引：0，他引：3  

余建国 《湖南地质》1998,17(3):155-159

本文结合古台山金锑矿床地质特征,着重分析了围岩蚀变类型及其分带,分布规律与矿化的关系,阐述了围岩蚀变特征及其找矿意义。  相似文献   

狮子山矿田矽卡岩型金矿铋矿物与金矿化关系研究   总被引：9，自引：0，他引：9  

任云生  刘连登  万相宗  陈国华 《矿物岩石》2004,24(2):41-45

包村和朝山金矿床位于安徽铜陵狮子山矿田，成因上属于矽卡岩型金矿。矿相学鉴定和电子探针分析结果表明，两矿床中的铋矿物以自然铋、辉铋矿为主，其次为碲铋矿、硫铜铋矿、辉铋铅矿等；铋矿物作为主要载金矿物．与自然金紧密共生；包村矿区Bi-Au相关系数为0．69，铋矿物与金矿化关系非常密切。成矿流体相分离引起的热液硫逸度fs2降低，可能是黑铋金矿分解成金和铋，并最终导致金与铋矿物密切共生的主要原因。  相似文献   

Ocean urea fertilization for carbon credits poses high ecological risks     

Glibert PM  Azanza R  Burford M  Furuya K  Abal E  Al-Azri A  Al-Yamani F  Andersen P  Anderson DM  Beardall J  Berg GM  Brand L  Bronk D  Brookes J  Burkholder JM  Cembella A  Cochlan WP  Collier JL  Collos Y  Diaz R  Doblin M  Drennen T  Dyhrman S  Fukuyo Y  Furnas M  Galloway J  Granéli E  Ha DV  Hallegraeff G  Harrison J  Harrison PJ  Heil CA  Heimann K  Howarth R  Jauzein C  Kana AA  Kana TM  Kim H  Kudela R  Legrand C  Mallin M  Mulholland M  Murray S  O'Neil J  Pitcher G  Qi Y  Rabalais N  Raine R  Seitzinger S  Salomon PS  Solomon C 《Marine pollution bulletin》2008,56(6):1049-1056

The proposed plan for enrichment of the Sulu Sea, Philippines, a region of rich marine biodiversity, with thousands of tonnes of urea in order to stimulate algal blooms and sequester carbon is flawed for multiple reasons. Urea is preferentially used as a nitrogen source by some cyanobacteria and dinoflagellates, many of which are neutrally or positively buoyant. Biological pumps to the deep sea are classically leaky, and the inefficient burial of new biomass makes the estimation of a net loss of carbon from the atmosphere questionable at best. The potential for growth of toxic dinoflagellates is also high, as many grow well on urea and some even increase their toxicity when grown on urea. Many toxic dinoflagellates form cysts which can settle to the sediment and germinate in subsequent years, forming new blooms even without further fertilization. If large-scale blooms do occur, it is likely that they will contribute to hypoxia in the bottom waters upon decomposition. Lastly, urea production requires fossil fuel usage, further limiting the potential for net carbon sequestration. The environmental and economic impacts are potentially great and need to be rigorously assessed.  相似文献   

中国北方寒武—奥陶系岩溶层组类型及其区域变化规律   总被引：3，自引：1，他引：2  

《中国北方岩溶地下水资源及大水矿区岩溶水的预测利用与管理的研究》项目综合组 《中国岩溶》1991,10(2):116-125

本文在大量剖面资料统计的基础上,根据岩层的厚度比例和连续厚度及其组合形式,对我国北方寒武—奥陶系岩溶层组类型进行了划分,着重论述了岩溶层组类型的区域变化规律。为含水层系统的划分和水资源评价及区域岩溶发育规律的研究,提供了重要的基础资料。   相似文献   

我国常用地基处理技术综述   总被引：1，自引：0，他引：1  

曾凡新 《化工矿产地质》2004,26(4):248-252

近年来,我国岩土工程地基处理方法可归纳为置换、排水固结、灌入固化物、振密或挤密、加筋、冷热处理、托换、纠倾等。具体处理常用换土垫层、砂井堆载预压、强夯、振动挤密、高压喷射注浆、深层搅拌、渗入性灌浆、加筋土、桩基础加固地基等方法。它们各自有一定的适用范围。  相似文献