冷原子无色散原子荧光法测定地球化学样品中的微量汞

本文阐述了用笔型低压汞灯为激发光源和氯化亚锡作还原剂的冷原子无色散原子荧光测汞方法。研究和比较了不同的激发光源,还原剂及载气。试验了38种共存元素的影响和干扰消除。对所报导的方法,在地球化学样品中含量低至9ppb的汞也得到良好的精密度。     

氢化物－原子荧光光谱法直接测定地质物料中痕量锗

采用特种空心阴极灯作激发光源和具有氩氢火焰低温自动点燃装置的原子荧光仪，氢化法直接测定地质物料中痕量锗，方法的测定下限为０．０２μｇ／ｇ，线性范围１～４００μｇ／Ｌ，精密度（ＲＳＤ，ｎ＝１１，１１６μｇ／ｇＧｅ）为１．７９％，加标回收率９７．８％。经标样和大批量样品分析验证，方法可靠实用     

GNSS-MR技术用于潮位变化监测分析

潮位变化的高精度监测一直是全球海平面观测系统、海洋环流和全球气候变化研究领域关注的热点问题之一。随着GNSS研究与应用的不断深入,近年来基于多路径效应的GNSS-MR技术已逐步成为一种新兴的遥感手段,即利用测量型GNSS站进行地表环境(植被、土壤湿度、雪深、潮位、火山活动等)监测。通过分析由多路径引起岸基GNSS站SNR值的变化特性,本文给出了基于SNR观测值的GNSS-MR技术监测潮位变化的反演原理。利用布设在美国华盛顿州Friday Harbor海港岸边的CORS站SC02实测观测数据对潮位变化监测进行了反演分析,并与该站相距359 m的验潮站数据进行了对比分析,两者较差均值约为10 cm左右,两者的相关系数均优于0.98。试验结果分析表明基于岸基CORS站的GNSS-MR技术在一定程度上可用于实时、连续的潮位变化监测,同时也说明岸基CORS站在一定程度上可作为验潮站的补充,进一步拓展GNSS在海洋遥感领域的应用范围。     

Seasonal Characteristics and Interannual Variability of Monthly Scale Low-Frequency Oscillation in a Low-Order Global Spectral Model

Analysis is done of five-year low-pass filtered data by a five-layer low-order global spectral model, indicating that although any non-seasonal external forcing is not considered in the model atmosphere,monthly-scale anomaly takes place which is of remarkable seasonality and interannual variability.Analysis also shows that for the same seasonal external forcing the model atmosphere can exhibit two climatic states,similar in the departure pattern but opposite in sign, indicating that the anomaly is but the manifestation of the adverse states, which supports the theory of multi-equilibria proposed by Charney and Devore(1979) once again.Finally, the source for the low-frequency oscillation of the global atmosphere is found to be the convective heat source / sink inside the tropical atmosphere as discussed before in our study.Therefore, the key approach to the exploration of atmospheric steady low-frequency oscillation and the associated climatic effect lies in the examination of the distribution of convect     

山西清徐地裂缝构造活动参数反演

利用精密水准监测数据,并结合工程地质勘查成果,构建了清徐地区浅部地裂缝与深部断层"双位错"模型,以此反演获取了地裂缝及断层现今的构造活动参数,确定了地裂缝与断层呈同倾向"Y"字形活动关系。结果表明,清徐地裂缝现今张裂活动速率大于倾滑活动速率,其量值达到了15.1mm.a-1;地裂缝活动下边界深度约在380 m左右;浅部地裂缝的倾滑速率大于深部断层的倾滑速率,断层倾滑速率仅为-1.6mm.a-1。反演结果与水文、地球物理勘测结果相一致。     

A Numerical Study of the Mechanism for the Effect of Northern Winter Arctic Ice Cover on the Global Short-Range Climate Evolution

By using a nine-layer global spectral model involving fuller parameterization of physical processes, with a rhomboidal truncation at wavenumber 15, experiments are performed in terms of two numerical schemes, one with long-term mean coverage of Arctic ice (Exp.1), the other without the ice (Exp.2). Results indicate that the Arctic region is a heat source in Exp.2 relative to the case in Exp.1. Under the influence of the polar heat source simulated, there still exist stationary wavetrains that produce WA-EUP and weak PNA patterns in Northern winter. That either the Arctic or the tropical heat source can cause identical climatic effects is due to the fact that the anomaly of the Arctic ice cover will directly induce a south-propagating wavetrain, and bring about the redistribution of the tropical heat source / sink. The redistribution is responsible for new wavetrains that will exert impact on the global climate. The simulation results bear out further that the polar region in Exp.2 as a heat source, can     

控制太阳活动的混沌吸引子(英)

随着非线性科学研究的进展,可利用表征太阳活动的太阳活动指数组成的时间序列来寻找或许存在的太阳混沌吸引子,并计算其关联维数、最大Lyapunov指数以及其它特征量．文中综述了用非线性科学的某些概念来研究太阳活动的进展及其在太阳活动预报方面的一些应用．     

BDS/GPS系统时差的组合实时预报模型分析

构造适用于BDS/GPS系统时差的多项式预报模型,对二次项参数选取、显著周期项确定以及观测权函数选择等进行改进。基于AR模型,进一步构建多项式和AR模型的组合时差预报方法。算例显示,新模型的单天时差预报精度优于0.4ns,显著优于其他传统方法。     

太阳黑子数月平均变化的长期行为的可预报性

本文用非线性动力系统理论探讨了现代太阳周（１８５０年１月─１９９２年５月）黑子相对数月平均变化过程的可预报性。用时间延迟方法重构吸引子，计算它的最大Ｌｙａｐｕｎｏｖ指数（λ_１＝０．０２３±０．００４ｂｉｔｓ／月），估算了用这些黑子数进行确定性预报的理论时限（ｔ＝３．６±０．６年）．结果表明，动力系统的可预报性与它的最大Ｌｙａｐｕｎｏｖ指数有直接关系，黑子数月平均变化过程的演化不是周期的，也不是拟周期的，而是混沌的。即使今后找到了描述该过程的确定性方程，它的长期行为也不可能准确地预报，只能作短期预报，这是黑子数本身的混沌特性决定的。用于黑子数预报的纯粹数值统计方法仅对短期预报才有效。