西藏拿若铜(金)矿床隐爆角砾岩流体包裹体研究

隐爆角砾岩是西藏拿若矿床的重要组成部分,赋存厚大的铜矿体。笔者将隐爆角砾岩中流体分成两个主要期次,并对这两期流体开展包裹体研究。通过包裹体岩相学和显微测温认为:角砾中的石英(早期)包裹体形状均匀呈椭圆形,大小主要在2~5μm;胶结物中石英(晚期)包裹体形状可见椭圆状、长条状和近方形,大小主要在2~7μm。早期流体的包裹体可分为两个阶段,均一温度分别为早阶段280~368℃和晚阶段208~305℃,盐度分布为(4.65~12.73)%Na Cleq。晚期流体的包裹体同样可分为两个阶段,其均一温度分别为早阶段309~588℃和晚阶段232~335℃,盐度变化为(3.55~12.51)%Na Cleq,两个阶段的流体分别属于高温、中低盐度和中高温、中低盐度流体。L-V型包裹体激光拉曼分析显示:包裹体中气泡成分主要为气态H2O和少量CO2。拿若矿床至少经历两次隐爆作用,由晚期沸腾热液引起,并未成矿。成矿作用发生于隐爆角砾岩形成之后。     

鄂尔多斯高原晚更新世以来的古冰缘现象及其气候地层学意义

本文概述了鄂尔多斯高第三系至全新统地层中融冻(衤习)皱和沙(土)楔两类古冰縁现象的分布与形态特征,探索了它们的成因以及同所在地层和上覆风成沙或黄土的关系,並对古冰縁现象的气候地层学意义作了讨论。     

检测前跟踪框架下利用蒙特卡洛算法的空间碎片跟踪策略研究（英文）

在轨卫星或者空间碎片数量的增多,是对空间目标地基自动观测的一个挑战。尽管北美防空司令部编目管理了绝大多数直径超过10 cm的空间物体,但由于轨道摄动,空间目标的位置信息(基于6个轨道根数)依然非常重要,并需要定期更新。在过去的几十年里,配备电子传感器的现代地基光电望远镜已广泛用于天体测量领域。然而,这种设备的跟踪性能主要取决于空间目标的大小和亮度。这些目标所在的天文图像会有不同的背景;而且,在基于凝视模式的短曝光实时观测过程中,运动目标和背景恒星在不同的信噪比下显示为类似的点扩散函数,难以辨认。本研究是为了实现对非高斯和动态背景的高灵敏度检测和跟踪能力的提高,并具有简单的系统机制和出色的计算效率。为突破该限制,将重点放在利用状态估计技术对微小卫星和暗弱目标进行跟踪上。提出一种基于神经网络的自适应运行高斯平均算法,用以从恒星背景及干扰下提取运动的空间目标。该方法随后被集成到了一个检测前跟踪框架中。该框架利用基于蒙特卡洛的粒子滤波跟踪空间目标。三段来自亚太地基光学空间目标观测系统(APOSOS)图像序列被用来对该跟踪策略进行评估。实验结果表明,该方法能够达到满意的跟踪性能。     

Bibliometric Analysis of Global Research Progress on Coastal Flooding 1995–2016

Global research progress on coastal flooding was studied using a bibliometric evaluation of publications listed in the Web of Science extended scientific citation index. There was substantial growth in coastal flooding research output, with increasing publications, a higher collaboration index, and more references during the 1995–2016 period. The USA has taken a dominant position in coastal flooding research, with the US Geological Survey leading the publications ranking. Research collaborations at institutional scales have become more important than those at global scales. International collaborative publications consistently drew more citations than those from a single country. Furthermore, coastal flooding research included combinations of multi-disciplinary categories, including ‘Geology' and ‘Environmental Sciences Ecology'. The most important coastal flooding research sites were wetlands and estuaries. While numerical modeling and 3 S(Remote sensing, RS; Geography information systems, GIS; Global positioning systems, GPS) technology were the most commonly used methods for studying coastal flooding, Lidar gained in popularity. The vulnerability and adaptation of coastal environments, their resilience after flooding, and ecosystem services function showed increases in interest.     

Prediction of one-dimensional compression behavior of Nansha clay using fractional derivatives

Nansha clay is an interactive marine and terrestrial deposited soft clay that is widely spread in Guangzhou, Pearl River Delta, China. To avoid excessive settlement after construction, there is a need for better quantifying the time-dependent deformation of the soft clay. This paper presents a preliminary study to predict the one-dimensional compression of Nansha clay using fractional derivatives. A fractional Merchant model was introduced to describe the time-dependent settlement, and analytical solutions were obtained in terms of the Mittag-Leffler function. The oedometer test results were presented to validate this model. Compared with classical rheological models, the fractional derivative-based model enabled close estimation of the one-dimensional compression with fewer parameters. The meaning of the order of fractional derivative and its relationship with the clay physical properties were explored. It shows that a smaller value of this order corresponded to a higher coefficient of consolidation and a lower coefficient of secondary consolidation. The amplitude of both the primary and secondary consolidation of clay may be estimated quantitatively by the order of fractional derivative. Taken together, these results may open up new avenues for theoretical and empirical modeling of rheological phenomena in clay using fractional derivatives.     

基于信息扩散理论的气象灾害风险评价方法

探讨了以灾害样本为集值的基于信息扩散的模糊数学理论模型的气象灾害风险评价方法,利用西北五省区主要农作物旱灾面积资料,对西北农业旱灾进行风险评价实例分析,通过比较表明西北农业受旱指数,成灾指数发生灾损的概率风险估计值与实际农业旱灾较吻合,该方法对灾害样本少以及小区域范围的灾害风险评价也较适合。     

渤海海域黄河口凹陷新近系多油水系统油藏成因分析

为明确同类油田的开发调整方向和潜力目标,以滚动勘探开发为目的,以A油田为例,探讨了黄河口凹陷中央构造脊北端新近系多油水系统油藏成因。储层与油源断层的有效配置是控制该类油气聚集的关键因素。基于已开发油田井震一体化精细地层对比和储层展布研究,细化了储层空间展布,并结合油源断层特征剖析,系统分析了储-断耦合对油气分布的控制作用。首先,油源断裂垂向活动强弱的差异与储层的匹配控制着油气垂向上主要聚集层位;其次,断裂平面发育程度的差异与储层展布的耦合控制着油气在平面上的分布;再次,储-断接触关系影响着油气的富集和赋存规律。     

Performance of A Combination Process of UV/H2O2/Micro‐Aeration for Oxidation of Dichloroacetic Acid in Drinking Water

The decomposition of dichloroacetic acid (DCAA) in water using a UV/H₂O₂/micro‐aeration process was investigated in this paper. DCAA cannot be removed by UV radiation, H₂O₂ oxidation or micro‐aeration alone, while UV/H₂O₂/micro‐aeration combination processes have proved effective and can degrade this compound completely. With initial concentrations of about 110 μg/L, more than 95.1% of DCAA can be removed in 180 min under UV intensity of 1048.7 μW/cm², H₂O₂ dosage of 30 mg/L and micro‐aeration flow rate of 2 L/min. However, more than 30 μg/L of DCAA was left after 180 min by UV/H₂O₂ combination process without micro‐aeration with the same UV intensity and H₂O₂ dosage. The effects of applied UV radiation intensity, H₂O₂ dose, initial DCAA concentration and pH on the degradation of DCAA have been examined in this study. Degradation mechanisms of DCAA with hydroxyl radical oxidation have been discussed. The removal rate of DCAA was sensitive to operational parameters. There was a linear relationship between rate constant k and UV intensity and initial H₂O₂ concentration, which indicated that a higher removal capacity can be achieved by improvement of both factors. A newly found nitrogenous disinfection by‐product (N‐DBP)‐DCAcAm, which has the potential to form DCAA, was easier to remove than DCAA by UV/H₂O₂ and UV/H₂O₂/micro‐aeration processes. Finally, a preliminary cost comparison revealed that the UV/H₂O₂/micro‐aeration process was more cost‐effective than the UV/H₂O₂ process in the removal of DCAA from drinking water.     

我国硫资源供需状况及需求预测

全球硫资源特征及国内硫资源供需现状表明,国内硫资源贫乏,硫资源生产与消费逐年增加,尤其磷肥生产对硫资源的需求越来越迫切,预计到2020~2025年磷肥用硫量将达到峰值1620万t左右,不包括出口磷肥耗硫量。因此,加强硫资源的综合利用、加大硫铁矿找矿及矿山设计是非常有必要的。     

某深基坑工程边坡变形失稳致因及处理对策

针对某深基坑工程在施工过程中,出现支护结构和邻近建筑物变形沉降增大、边坡有失稳滑移的危险状况,采用场地水文地质特性调查、边坡支护方案模拟计算与施工监测数据分析相结合的研究方法,确定场地中对施工扰动敏感性强的原状粉土和粉细砂层的沉降是导致基坑边坡失稳的主因,采用土层锚拉加固方案取代对地层扰动较大的注浆排险方案,确保了基坑安全开挖和边坡的最终稳定。