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321.
With the rise of low carbon economy and the deterioration of the international energy situation, most countries in the world pay more attention to energy issues. In this paper, based on a comparison with several countries of large energy consumption, we used long sequence statistics to analyze the energy consumption characteristics from the world and the history, including energy consumption, energy consumption structure and energy efficiency, and then summed up the characteristics of energy consumption in developed countries, analyzed China's energy consumption process and the current stage, and found out the main problems of energy consumption in China. At last, countermeasures for the healthy development of China's energy were proposed, including actively promoting scientific and technological progress, upgrading energy structure, developing low carbon economy, rationalizing energy prices, improving the proportion of clean energy consumption and emphasizing synergistic effect on environment protection.  相似文献   
322.
Large-scale, low frequency modes such as the North Atlantic Oscillation(NAO)and blocking, have an important modulation on the northern hemisphere weather and climate. In this paper, the physical mechanism studies on inter-decadal and decadal variability of NAO and blocking were summarized. The relationship between NAO regime transitions and the interannual variability of NAO in winter during was examined by using a statistical approach. The time-space relationship between NAO and European blocking were discussed. Based on two extreme cold and snowstorm events, the impacts on local weather especially the extreme events within the life cycle (two weeks) of the NAO and blocking were further examined. It was found that the frequently occurrence of the Eurasian extreme snowstorm was closely related to the special combination of NAO and blocking regime. In addition, the development of theoretical modes for NAO and blocking was discussed and issues that remain to be solved were proposed.  相似文献   
323.
滑坡的时间-位移曲线一般具有3个阶段特征,即初始变形阶段、等速变形阶段和加速变形阶段,不同演化阶段加速度具有不同的变化特点.目前往往是依据对加速度曲线特征的分析来人为划分演化阶段,缺少相应的理论支持和定量计算.针对上述问题,选取月降雨量、月库水位高程变化量对滑坡的累计位移建立多因素的时间序列预测模型.然后利用Chow分割点检验理论,以所建模型中F和LR统计量最大值点作为分割点对滑坡演化阶段进行划分.以新滩滑坡和三峡库区白水河滑坡为例,利用累计位移、降雨及库水位变化数据进行计算验证.结果表明,对多元时间序列模型进行Chow分割点检验可对滑坡的演化阶段进行准确划分,为滑坡的临滑预警预报提供重要判据.   相似文献   
324.
WFSD-4S孔流体地球化学特征   总被引:1,自引:0,他引:1       下载免费PDF全文
本文开展汶川地震断裂带科学钻探现场流体研究,探讨了泥浆添加剂产生的化学反应以及钻孔中岩性变化引起的流体异常特征,并在排除这些影响因素的情况下,讨论地震期间流体的异常。研究表明在WFSD-4S钻进期间发生的两次较大地震前均伴有Rn、Ar、N2和O2等气体异常现象,其中氡的日均值均超出背景值的2.5倍。根据岩心观察得到WFSD-4S钻井地区主断层约在1084 m,而在断层之上931 m处开始出现了大量气体的高值异常,该异常可能是由于地震孕育过程中地下气体的运移通道被打开造成气体向上迁移,使断层气体的响应特征提前发生。  相似文献   
325.
A three-dimensional (3D) structural modeling of the Lower Cambrian–Upper Permian Yubei 3D area was performed to understand its structural evolution. This model reproduces the present-day structure of the basin and comprises 11 horizons within Lower Cambrian to Upper Permian rocks. The analysis is based on 3D depth views and faults. The results image salt movements due to tectonics and/or burial. From these observations, this paper deduces that salt structures are correlated to the main faults and tectonic events. From the model analysis, we interpret the timing and geometry of Tarim Basin tectonics. The fault geometry can be resolved based on the strike of the fault, the morphology of hanging wall strata, and the stratigraphic distribution. Emphasis is placed on gypsum rock detachment, considering its movements during the Middle Caledonian event and decoupling effects during tectonic evolution. Moreover, we point to the structural control of the Paleozoic basement and the crustal architecture (Yubei 3D Zone) on the geometry of the Tarim Basin.  相似文献   
326.
强潮流作用下桥墩不对称“双肾型”冲刷地貌特征与机理   总被引:1,自引:0,他引:1  
本文在海图地形资料分析桥轴线附近的海床自然冲刷的基础上,利用多波束测深技术研究大桥主墩附近局部冲刷地形。结果表明,该大桥桥位附近地形冲刷较显著,且大桥主墩位置有持续冲刷的趋势;主墩上、下游群桩最大冲刷深度呈上游最深、中部淤积、下游渐深的不对称形态,最大局部冲刷深度为4 m;桥墩整体冲刷坑形态呈南北“双肾型”;潮流流向与桥墩迎流面存在偏南的入射角,使得各桥墩南侧的最大冲深和冲刷范围均大于北侧。  相似文献   
327.
青岛冷水团的消亡机理研究   总被引:1,自引:0,他引:1  
本文基于多年月平均水温资料,分析了青岛冷水团的长消过程,并利用气候态月平均大气数据和数值模拟结果,探讨了青岛冷水团的消亡机理。结果表明,青岛冷水团3月出现,4月成型,5月最盛,6月减弱,7月消失;南黄海6-7月间偏南风的增强和温跃层以下反气旋涡的减弱是青岛冷水团消亡的动力机制,而海面净热通量的下传和水平热量的输入则是青岛冷水团消亡的热力机制。  相似文献   
328.
在登陆海南岛之前,台风威马逊在南海北部从热带风暴级别迅速增强成为超强台风。观测数据的分析结果显示,海洋上层的异常暖水在威马逊的迅速增强过程中扮演了重要的角色。威马逊期间,南海北部的海表面温度相比于气候态海表面温度暖很多。这部分异常暖水为威马逊提供了更多的能量,从而导致了威马逊的迅速增强。数值模拟结果进一步证明,南海北部的暖水在台风威马逊的迅速增强过程中起重要作用。如果没有这团异常暖水的影响,威马逊只增强25 hPa,仅为有暖水影响条件下增强程度的58.1%。  相似文献   
329.
Incubation experiments were adopted to characterize the rates and pathways of iron reduction and the contributions to anaerobic organic matter mineralization in the upper 0–5 cm of sediments along a landscape-scale inundation gradient in tidal marsh sediments in the Min River Estuary, Southeast China. Similar sediment characteristics, single-species vegetation, varied biomass and bioturbation, distinct porewater pH, redox potential, and electrical conductivity values have resulted in a unique ecogeochemical zonation along the inundation gradient. Decreases in solid-phase Fe(III) and increases in nonsulfidic Fe(II) and iron sulfide were observed in a seaward direction. Porewater Fe2+ was only detected in the upland area. High rates of iron reduction were observed in incubation jars, with significant accumulations of nonsulfidic Fe(II), moderate accumulations of iron sulfides, and negligible accumulations of porewater Fe2+. Most of the iron reduction was microbially mediated rather than coupled to reduced sulfides. Microbial iron reduction accounted for 20–89 % of the anaerobic organic matter mineralization along the inundation gradient. The rate and dominance of microbial iron reduction generally decreased in a seaward direction. The contributions of microbial iron reduction to anaerobic organic matter mineralization depended on the concentrations of bioavailable Fe(III), the spatial distribution of which was significantly related to tidal inundation. Our results clearly showed that microbial iron reduction in the upper sediments along the gradient is highly dependent on spatial scales controlled primarily by tidal inundation.  相似文献   
330.
淤泥质潮滩地貌演变中的水动力及生物过程研究进展   总被引:2,自引:0,他引:2  
王宁舸  龚政  张长宽  赵堃  耿亮 《海洋工程》2016,34(1):104-116
淤泥质潮滩对于海岸防护、增加土地资源、保持生物多样性等具有重要作用。从淤泥质潮滩演变的主要驱动因子——潮流、波浪、生物作用及地下过程四个方面回顾和总结了潮滩演变动力地貌过程的相关研究进展,提出应关注潮滩短期演变规律、波浪与浮泥作用机理、生物生长与潮滩演变定量关系,以及地下过程作用机理等。  相似文献   
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