滨州市海域海冰的时空分布和冰级特征

文章根据2005—2017年滨州市海域冬季各类海冰监测数据资料,对冰日、冰期、冰型、冰厚、浮冰密集度和结冰范围等冰情要素进行分析,总结海冰的时空分布和冰级特征,为进一步开展相关海域的海冰灾害研究和防灾减灾工作提供必要的参考。研究表明,滨州市海域的总冰期一般为60~80d,其中严重冰期约为25d,河口和浅滩等近岸海域冰情较重;冰型、冰厚和结冰范围等在不同冰期和冰级具有不同特点,对海上设施和海上活动造成不同程度的影响。     

基于星间链路体制的北斗卫星时间同步可行性分析

BD-3试验星上搭载了Ka频段星间链路（ISL）设备,可进行Ka波段对地观测。推导了星间链路时分观测体制双向时间同步的数学模型;以ISL星地观测数据为样本分析ISL体制时间同步的可行性,并与L波段观测结果比对。结果表明,ISL体制钟速拟合参数与L波段结果一致性较好,7 d和3 d弧段拟合精度在1 ns以内,1 d和1 h弧段拟合精度均在0.2 ns以内,较L波段拟合精度有所提高,其中1 d为最优拟合时长;利用7 d的实测星地钟差进行向后1 d的钟差预报,结果显示,ISL星地钟差1 d预报误差为2 ns,较L波段预报精度略有提高;最后采用星地星间联合钟差观测,2 d内观测残差为0.52 ns,验证了ISL钟差观测的可行性。     

滇池入湖河流磷负荷时空变化及形态组成贡献

研究了2013年滇池主要入湖河流总磷(TP)及各形态磷浓度的时空变化与入湖负荷特征,并探讨了不同形态磷的入湖负荷贡献.结果表明:(1)滇池河流入湖TP浓度在0.11~1.93 mg/L之间,以溶解性无机磷(DIP)和颗粒态磷(PP)为主,溶解性有机磷(DOP)浓度较低;(2)滇池河流入湖磷负荷总量为280.51 t/a,绝大多数河流主要以DIP形态入湖,平均贡献率为43.48%;PP形态入湖负荷次之,平均贡献率为31.64%;DOP入湖负荷较低,平均贡献率为24.88%;(3)DIP入湖负荷贡献率较高值出现在3、4和11月的枯水期,平均入湖负荷贡献率达到55.30%;PP入湖负荷贡献率较高值出现在1和7月,平均入湖负荷贡献率为56.14%;DOP入湖负荷贡献率月变化差异较小,最高值出现在12月,贡献率为21.85%;(4)研究滇池入湖河流污染负荷不仅要考虑溶解态无机磷的贡献,而且需要重视PP和DOP负荷,控制滇池入湖河流污染负荷需要考虑不同河流不同形态磷负荷组成及月变化差异特征,有针对性地采取相应措施.     

外核黏性对地磁场发电机数值模型的影响

地磁场发电机过程由数学方程组和输入参数所控制.为研究发电机参数对系统的影响,本文使用MoSST模型模拟了在外核黏性ν变化下发电机模型的输出.通过使用跨越近3个量级的ν值,着重研究了各物理场及其典型尺度随黏性的变化.发现黏性变化显著影响流场;磁场随ν增加而近乎单调减小,但变化幅度不超过30%;温度扰动随ν增加而小幅（6%）单调增加.经过拟合,得到外核流速u和黏性ν的比例关系：u~ν^0.49.流速随黏性增加的现象本质上是由于黏性增加打破了Taylor-Proudman约束,使得临界Rayleigh数减小,从而在相同的驱动力下带来了流速的增加.此外,作用力平衡分析发现,随着ν的变化,系统在几种平衡模式间切换.通过与之前比例关系的研究对比,本研究支持在一定范围内,磁场与黏性关系不大的结论;但反对流速与外核黏性无关的假设.     

马里亚纳海沟万米级水文观测研究

深渊观测是开展深渊科学研究的前提。文章介绍了2020年7月"东方红3"船在马里亚纳海沟"挑战者深渊"附近完成的一次海洋调查。基于船载温盐深综合剖面测量系统获取的万米级剖面数据,分析全海深的温盐性质,并依据Thorpe尺度方法和细尺度参数化方法,进一步估算不同深度层的湍动能耗散率。结果表明:"挑战者深渊"的深层海水十分稳定, 3 000—5 000 dbar的温盐特征与下层绕极水相同;受弱层结背景下的内潮影响, 5 000—8 000 m的耗散率显著提升。本次调查获取的万米级水文剖面为马里亚纳海沟的深渊探索提供了数据方面的支撑。     

TWO DIMENSIONAL MODEL ON RELATION BETWEEN THERMAL ANOMALY BEFORE WENCHUAN EARTHQUAKE AND TECTONIC STRESS

It has been reported that there is thermal anomaly within a certain time and space preceding an earthquake, and previous research has indicated potential associations between the thermal anomaly and earthquake faults, but it is still controversial whether physical processes associated with seismic faults can produce observable heat.Based on rock experiments, some scholars believe that the convective and stress-induced heat associated with fault stress changes may be the cause of those anomalies. Then, did the thermal anomaly before the Wenchuan earthquake induced by the fault stress change?It remains to be tested by numerical simulations on the distribution and intensity of thermal anomalies. For example, is the area of thermal anomaly caused by the fault stress changes before the earthquake the same as the observation?Is the intensity the same?To clarify the above questions, a two-dimensional thermo-hydro-mechanical(THM)finite element model was conducted in this study to simulate the spatial and temporal variations of thermal anomalies caused by the underground fluid convection and rock stress change due to the tectonic stress release on fault before earthquake. Results showed that the simulated thermal anomalies could be consistent with the observed in magnitude and spatio-temporal distribution. Before the Wenchuan earthquake, deformation-related thermal anomalies occurred mainly in the fault zone and its adjacent hanging wall, which are usually abnormal temperature rise, and occasionally abnormal cooling, occurring in the fault zone after the peak temperature rise. In the fault zone, the thermal anomaly is usually greater than the order of 1K of the equivalent air temperature and is controlled by the combined effect of fluid convection and stress change. The temperature increases first and then decreases before the earthquake. In the hanging wall, it's weaker than that of the fault zone, mainly depending on the convection of the fluid. The temperature gradually increases before the earthquake and is dramatically affected by the permeability. Usually, only when the permeability is larger than 10^-13m², can the air temperature rise higher than 1K occur. The results of this study support the view that fluid convection and stress change caused by fault slip before the earthquake can produce observable air temperature anomalies.     

Classification of Magmatic Sulphide Deposits in China and Mineralization of Small Intrusions

Many important metal resources, such as Ni （Cu, Co）, PGE, exist in magmatic sulfide deposits, are a hot spot in geological research. We divide the magmatic sulphide deposits in China into four types according to their tectonic setting, intruding mode, ore deposit mode, main metallogenic elements. The four types are as follows： （1） Small-intrusion deposits in paleo-continent; （2） Smallintrusion deposits in continental flood basalt; （3） Small-intrusion deposits in orogenic belt; and （4） The deposits associated with ophiolites. On the basis of the classification, we put forward that the main magmatic metallogenic type in China is small-intrusion metallogeny, and describe its characteristics from small intrusions related concept, three geologic settings, three volcanic-intrusive assemblages and metallogenic key factors. According to the experiences of prospecting at home and abroad, we point out that there is big potential in prospecting small-intrusion deposits, which need further study. At last, we indicate that small-intrusion metallogeny not only widely distributes in mafic-ultramafic intrusions, but also has an important economic value and scientific significance in intermediate-acid intrusions.     

基于集群视角的煤炭城市产业转型研究——以安徽淮南市为例

20世纪90年代以来,煤炭城市发展出现了经济衰退、竞争力下降等一系列问题,如何实现煤炭城市的产业转型是社会关注的热点。文章分析了煤炭城市产业转型中的集群效应,认为立足于传统产业优势,发展煤炭产业集群是煤炭城市实现依托式产业转型的有效途径。在此基础上,探讨了淮南市煤炭产业群发展现状及特征,提出了煤炭产业群的发展思路。     

降水临近预报及其在水文预报中的应用研究进展

随着全球气候变化、自然变迁及陆表生境改变,极端天气频发且呈现出多尺度时空变异特征,对其进行预报和预警一直是气象水文领域关注的焦点。临近预报可较准确地预报未来短时间天气显著变化,是当前预报强降水等极端事件的主要手段。从基于天气雷达0~3 h外推临近预报、融合数值模式0~6 h临近预报的发展历程梳理了临近预报的研究进展,阐述了雷达外推算法的发展进程、雷达外推预报与数值模式预报融合技术进展,指出"取长补短"的0~6 h融合预报在提高降水预报精度、延长降水预见期等多方面有较大的发展潜力,进一步探寻及提升融合技术是未来融合预报发展的核心。将临近预报以气象水文耦合的方式引入水文预报是从源头提高水文预报精度、保障水文预报效果的主要途径,总结了现阶段主流耦合方式、空间尺度匹配技术、水文模型不确定等陆气耦合中的关键问题,阐述了外推临近预报、融合临近预报作为水文预报输入的研究进展,明确了融合临近预报在延长洪水预见期、提高洪水预报精度中存在优势,并讨论了未来的研究重点及发展方向。     

充气膨胀控制锚杆的研制与试验

现有充气锚杆构造存在着承载力小、气囊易爆破、无法在工程中应用等缺点。通过对充气锚杆的气囊增加保护用的端挡板、侧护板等措施,分别发明了带端挡板的充气锚杆和带侧护板的充气锚杆;又在锚杆的构造中增设挤土钢板,改变了锚杆的传力途径,研制出管片式充气膨胀控制锚杆,具有承载力大、性能稳定、可完全回收等特点,整体构造更加简单实用。对这3种锚杆分别进行了室内外黏土层的足尺试验,管片式充气锚杆的最大充气压力可以达到0.6 MPa,是现有充气锚杆的5倍,锚固段每米极限承载能力最大达到40 kN,是现有充气锚杆的60倍;同时推导验证了管片式充气膨胀控制锚杆的承载力计算公式,使得该类锚杆的工程应用成为可能。