有限区域短期数值预报业务系统简介          下载免费PDF全文

茅卫平  马华平  郭卫东  李振军 《气象》1995,21(4):37-42

简要介绍了空军气象中心投入业务使用的《空军有限区域短期数值预报业务系统》的概况、采用的主要技术，检验评分结果，最后给出了天气学个例检验结果。  相似文献   

电子探针分析与系列矿物研究   总被引：2，自引：0，他引：2  

毛水和 《矿物学报》1987,(2)

本文论述以电子探针为主要测试手段对下述几种系列矿物的研究成果:(1)铂族元素系列矿物的研究(包括Ru-Os-Fe金属互化物矿物系列和RuAs_2-OsAs_2二元固溶体矿物系);(2)Au-Cu系列矿物的研究;(3)黝铜矿族矿物的研究。  相似文献   

应用图象识别法预测强震危险区存在的问题及讨论          下载免费PDF全文

毛卫民 《地震工程学报》1982,4(4):120-123

应用图象识别法预测强震危险区虽然国内外都有报道,但也还存在一些问题,近来国内已有人发现,用图象识别法确定地震危险区存在一些缺陷,它直接影响到结果的可靠程度。为了进一步从理论上搞清产生这些问题的根源及其规律,下面我们就两类图象识别问题的数学模型,根据线性不等式组的理论进行严格的数学讨论。  相似文献   

The Southern part of the Armorican orogeny: A result of crustal shortening related to reactivation of a pre-Hercynian mafic belt during Carboniferous time     

J.P. Lefort  Cl. Audren  M.D. Max 《Tectonophysics》1982,89(4):359-377

This synthesis of detailed geological and geophysical information relates deep crustal structure to deformation and the emplacement of granites in the South Armorican Massif and the adjacent continental shelf. Near the continental margin a zone of geophysical anomalies is regarded as a nearly complete line of suture between a southern continent and America. A major mafic body in the trace of the supposed suture in interpreted as a relic of probable oceanic crust which has apparently acted as a deflector of regional strain.It is proposed that late in the Hercynian collision history, during late Carboniferous time, compressional strain acted across the mafic body and can be directly related to generation of younger regional structures in the metasediments and to localization of granite emplacement.  相似文献   

Crustal transit time monitoring using PKP     

Max Wyss  R. Kind 《Pure and Applied Geophysics》1983,121(2):269-285

The arrival time difference for the AB branch of PKP from deep Tonga earthquakes is constant over years with a standard deviation of ±0.05 seconds at seismographs located 10 to 50 km from each other. If published travel time curves are used to calculate the relative residuals of PKP the standard deviation from the constant mean is improved by approximately 0.01 seconds for AB branch data. For the BC branch, standard deviations of relative travel times of ±0.06 seconds are reduced to less than ±0.05 seconds by calculating relative residuals. We conclude that changes of crustal transit time forP-waves could be resolved, based on careful PKP arrival time measurement at two or more neighboring stations if the changes exceed 0.05 sec and last for more than one year. The conditions for achieving this result are that PKP from Tonga earthquakes is clearly recorded, and that time-keeping is accurate. The data on which these conclusions are based were obtained from the Graefenberg seismograph array, which is located in West Gemany and consists of 13 stations separated by distances of 10 km to 100 km. We propose that relative arrival times of PKP from Tonga could be used in the Mediterranean - Middle East area to search for precursory travel time changes before large earthquakes.  相似文献   

Carbon and hydrogen isotopic compositions of the NBS 22 and NBS 21 stable isotope reference materials: An inter-laboratory comparison     

Martin Schoell  Eckhard Faber  Max L. Coleman 《Organic Geochemistry》1983,5(1):3-6

Measurement of 17 laboratories on the stable isotope reference materials, NBS 22 lubricating oil and NBS 21 graphite, resulted in a revised calibration on the PDB scale. NBS 22 ¹³C/¹²C ratios of all laboratories did not demonstrate a gausssian distribution. Therefore, values which resulted from direct comparison with NBS 20 carbonate standards were selected the mean value of which is $\text{?29.81 ± 0.06?}$; this value is recommended as new value for NBS 22. The reported variations in δ¹³C for NBS 21 were consistent within the accuracies for single meaurements; the mean value is ?28.16 ± 0.01. The variations of D/H ratios of NBS 22 also were consistent with the accuracy quoted, with a mean value of ?119?.  相似文献   

山东归来庄金矿区g(Au/Ag)的空间信息统计学特征     

肖斌  潘懋  赵鹏大  侯景儒 《地质科学》2001,36(4):500-508

空间信息统计学是一门集数学、空间信息科学及计算机技术于一体,在时空域内对区域化变量的随机性与结构性进行定量研究的技术。以山东归来庄金矿床为例,对其g(AuAg)异常进行空间信息统计学研究。利用指示克立格法研究g(AuAg)的空间变异结构特征,建立空间结构模型。在对结构模型和估计方案进行交叉验证后,对g(AuAg)的空间分布进行估计。根据g(AuAg)的空间分布规律,探讨其与Au空间分布的关系,并对今后该区的找金工作提出建议。  相似文献   

高表面活性矿物对Zn~(2+)的吸附机理及其环境意义     

吴平霄  廖宗文  毛小云 《矿物学报》2001,(3)

本文利用高表面活性矿物蒙脱石、蛭石、沸石在一定的介质条件下对Zn2 +进行吸附实验研究。蒙脱石和蛭石对Zn2 +的等温吸附线呈双“S”型 ,而沸石对Zn2 +的等温吸附线则呈“Langmuir”型。三种矿物对Zn2 +的吸附容量大小顺序为 :蒙脱石 >蛭石 >沸石。运用粉晶X射线衍射、红外光谱、差热及热重分析等技术对矿物及矿物吸附Zn2 +后的结构特征进行了研究。结果表明 ,蒙脱石吸附锌后其层间域中吸附锌大量水解形成新的物相 ,而蛭石与沸石吸附锌后水解很少。这为利用高表面活性矿物控制和治理环境污染及其可循环利用提供了理论依据。  相似文献   

Comment on 'The magnetotelluric phase tensor' by T. Grant Caldwell, Hugh M. Bibby and Colin Brown   总被引：1，自引：0，他引：1  

Max Moorkamp 《Geophysical Journal International》2007,171(2):565-566

We demonstrate a minor inconsistency in the appendix of 'The magnetotelluric phase tensor' by Caldwell et al. that can lead to incorrect results, and provide a simple solution for this problem.  相似文献   

The harmonious character in equilibrium aeolian transport on mixed sand bed   总被引：1，自引：0，他引：1  

Mao Xing   《Geomorphology》2007,86(3-4):230-242

Wind tunnel experiments were carried out to measure the spatial distribution in equilibrium transport of four types of mixed sand. The flux profiles of each grain size group were calculated. It is found that the vertical distribution of mean grain size has a close relation with the grain size distribution in the sand bed. In a log-linear plot, the flux profiles of main grain size groups are all straight lines and their slopes are nearly equal. It is also found that the ratio of transport rate of each size group to the whole transport rate is directly proportional to the mass ratio of each size group in the sand bed and the proportion value is only dependent on the grain size. This harmonious law is applicable to all four types of mixed sand used in the experiment.  相似文献