微型堆仪器中子活化分析测定水系沉积物中多个元素

本实验以微型核反应堆为中子源用仪器中子活化分析对水系沉积物中的30个元素常规测定进行了研究。样品在长照射后从第四天开始直到第八天进行每天一次的跟踪测试。研究了有关元素的最佳冷却时间,从而得到了最佳探测限。以GSD-11和GSD-8为标准监控样品,对实验结果的精密度和近似检测限进行了计算。长照测试元素La、Sc、As、Sb、Na、W、Gd和Sm的相对标准偏差小于5％,Th、U、Yb、Ta、Rb、K、Fe小于10％,Ho、Ce、Ga、Lu、Br小于15％,Eu、Cs小于20％。短照测试元素为Mg、Al、Mn、     

阿拉善地块北缘雅干花岗岩体地球化学、地质年代学及其对区域构造演化制约

位于阿拉善北部中蒙边境地区的雅干花岗岩体以二长花岗岩为主,岩体的锆石离子探针U-Pb年龄为283.2±2.2Ma (n=14,MSWD=0.016).该花岗岩体具有相对较低的SiO2含量(66.96％～70.71％),和较高的A12O3(15.05％～16.05％)和(Na2O+ K2O)含量(7.24％～9.19％),且岩体钠含量稍高(Na2O/K2O＞1).雅干花岗岩体总体上表现为高钾钙碱性及偏铝质-过铝质的特征.岩体稀土元素总合量为101.9×10-6～133.1 ×1O-6,在稀土元素配分模式图中,岩体表现为轻-重稀土元素中等程度-强烈分异,同时具有明显的负Eu异常(δEu =0.59 ～0.77);在微量元素原始地幔标准化蛛网图中,岩体表现为亏损Nb、Ta、P、Ti,富集Ba、Rb、Cs、Th、K等大离子亲石元素;岩体同位素特征则表现为具有高的(87 Sr/86 Sr)i值(0.707654 ～0.710235)以及负εNd(t)值.根据雅干花岗岩体的形成时代、地球化学特征以及相关的沉积建造特征,可推断该岩体形成于后碰撞环境,表明古亚洲洋在阿拉善地块北缘北部地区的分支于早二叠世(283.2 ±2.2Ma)之前已经闭合.     

2001年昆仑山口8.1级巨震后中国大陆、云南地震趋势研究

分析研究了2001年11月14日昆仑山口8．1级巨震对中国大陆云南未来几年地震趋势的影响，指出巨震后6年大陆可能仍然处于地震活跃期，其间大陆西部发生7．0级以上大震可能性较大；受2000－2001年欧亚带东南段大震活动过程及巨震调整影响，未来1－3年云南省可能进入新的活跃期，6．5级以上强震危险性增加。     

大气热力学的若干新发展

对自20世纪80年代以来的大气热力学发展进行了综合评述, 阐述了如城市热岛效应、全球增暖等非传统大气热力学问题; 基于大气非平衡态热力学的非线性理论, 提出应发展突显热力学作用的数值模式, 并阐述其必要性和可能性。     

A Catalog of Luminous Infrared Galaxies in the IRAS Survey and Second Data Release of SDSS

We selected a sample of luminous infrared galaxies by cross-identification of the Faint Source Catalogue (FSC) and Point Source Catalogue (PSC) of the IRAS Survey with the Second Data Release of the SDSS. The size of our sample is 1267 for FSC and 427 for PSC by using the 2σ significance level cross-section. The "likelihood ratio" method is used to estimate the individual's reliability and for defining two more reliable subsamples (908 for FSC and 356 for PSC). A catalog of infrared, optical and radio data is compiled and will be used in further work. Some statistical results show that luminous infrared galaxies are quite different from ultra-luminous infrared galaxies. The AGN fractions of galaxies at different infrared luminosities and the radio-infrared correlations are consistent with the previous studies.     

The smoke is rising but where is the fire? Exploring effective online map design for wildfire warnings

The current study sought to offer guidance for developing effective web-based mapping tools for wildfire warnings by identifying (1) the important content for facilitating individuals’ decision-making, and (2) the optimal interface design for ensuring usability and ease of information access. A map-based warning tool was prototyped in the Australian context, followed by a usability and effectiveness evaluation through individual interviews and verbal protocol analysis to assess participants’ interaction with the mapping interface and information in response to the simulated warning scenario. The results demonstrated variations in participants’ approaches to wildfire warning response, revealing varied information needs. Specifically, most participants relied on their own assessment of the prospective threat, requiring specific wildfire-related information before eliciting a response. In contrast, the decision of a minority of the participants was motivated by response guidance from agencies, and accurate wildfire information was less important for their response. Imperative information for both types of residents therefore needs to be highlighted in a map-based warning tool to cater to a wide audience. Furthermore, a number of heuristics were identified for designing effective interactive functions to facilitate the control of, and access to, the various maps and textual information presented on the map-based warning interface.     

黄海的风、潮混合特征及其对冷水团边界的影响

本文第一作者早在1985年就提出,潮混合效应控制着夏季黄海冷水团的边界及海面冷水分布(赵保仁,1985)。1987年又进一步通过水文调査资料和卫星图片给出了黄海周围的浅水陆架锋(或称潮汐锋)的分布及强锋区的跨锋断面中的温度、盐度和坏流结构特征,并指出夏季的黄海沿岸流在性质上属沿锋面运动的强流(赵保仁,1987a,b),而后又对黄海西部的陆架锋进行了一次专门调査(赵保仁等,1991)。此外,他还指出黄海的强温跃层的形成和转移现象也与潮混合现象密切相关(赵保仁,1989)。因此,研究潮混合现象对阐明发生在黄海的多水文物理现象都是至关重要的。 为深入了解黄海的潮混合特征,作者把渤海、黄海和东海作为一个整体完成了一次精度较高的潮汐、溯流数值计算,在潮汐、潮流的分布方面,揭示了前人尚未阐明的一些特征。本文根据这些数值结果,计算了近最大潮流流速和层化参数,阐明了渤海、黄海和东海的潮混合特征及其对降温期黄海冷水团分布变化的影响。此外,还用 Sim pson等人(1981)的能量模式计算了南黄海西部的风、潮混合效率。     

Self-Weight Penetration Characteristics of the Suction Foundation with Different Diameters in Sand

During the self-weight penetration process of the suction foundation on the dense sand seabed, due to the shallow penetration depth, the excess seepage seawater from the outside to the inside of the foundation may cause the negative pressure penetration process failure. Increasing the self-weight penetration depth has become an important problem for the safe construction of the suction foundation. The new suction anchor foundation has been proposed, and the self-weight penetration characteristics of the traditional suction foundation and the new suction anchor foundation are studied and compared through laboratory experiments and analysis. For the above two foundation types, by considering five foundation diameters and two bottom shapes, 20 models are tested with the same penetration energy. The effects of different foundation diameters on the penetration depth, the soil plug characteristics, and the surrounding sand layer are studied. The results show that the penetration depth of the new suction foundation is smaller than that of the traditional suction foundation. With the same penetration energy, the penetration depth of the suction foundation becomes shallower as the diameter increases. The smaller the diameter of the suction foundation, the more likely it is to be fully plugged, and the smaller the height of the soil plug will be. In the stage of self-weight penetration, the impact cavity appears around the foundation, which may affect the stability of the suction foundation.

     

Formation of saddle dolomites in Upper Cambrian carbonates, western Tarim Basin (northwest China): Implications for fault-related fluid flow

The saddle dolomites occur more intensely in cores closely to fault than that in cores far away from the fault in Upper Cambrian carbonate of western Tarim basin, suggesting that formation of the saddle dolomites is likely related to fault-controlled fluid flow. They partially fill in fractures and vugs of replacement dolomite. The saddle dolomites exhibit complex internal textures, commonly consisting of core and cortex. In comparison with the matrix dolomites, the saddle dolomites show lower Sr-content and ⁸⁷Sr/⁸⁶Sr ratios, higher Fe- and Mn-content, and more negative δ¹⁸O values. Combined with high Th (100–130 °C) of primary fluid inclusions, it is suggested that the saddle dolomites precipitated from hydrothermal fluid derived from the deep evaporite-bearing Middle Cambrian strata, and the magnesium source may be due to dissolution of host dolomite during hydrothermal fluid migration. Fault activity resulted in petrographic and geochemical difference of the core and cortex of the saddle dolomites. The cores precipitated from the formation water mixed by deep brines at the early stage of fault activity, and the cortexes precipitated from the deep fluid with higher temperatures through the Middle Cambrian later. In summary, the formation of the saddle dolomites implies a hydrothermal fluid event related to fault activity, which also resulted in high porosity in Upper Cambrian carbonate in western Tarim Basin.     

兰州倾斜固体潮潮汐参数的观测研究

本文介绍了兰州形变台FSQ—水管倾斜仪1987—1989年期间观测资料的调和分析结果,讨论了潮汐因子的重复性及其对非潮汐变化的监测能力,分析了气象因素对周日波的影响,並将实测潮汐因子与G—B地球模型理论值进行了比较。