陕西地震监测台网恢复重建与通讯网络改造     

张宇翔  罗词建  罗治国  李媛媛 《地震地磁观测与研究》2011,32(5):123-127

陕西地震监测台网震后恢复重建项目实施过程中,通过优化台网布局和增加台网密度,新建GNSS连续观测系统,提高了地震监测能力;采用的通讯网络新架构以及OSPF路由协议,不仅提升了监测网络通讯系统的可靠性,而且取得降低通讯费用的显著成效.  相似文献   

A study on the effects of the surrounding faults on water loss in the Zoige Wetland, China   总被引：1，自引：1，他引：0  

Mei Li  Rui Xu  Wendian Huang  Hailong Sun  Lin Luo 《山地科学学报》2011,8(4):518-524

The Zoige wetland is the biggest alpine wetland in the world,and an important water resource of the Yellow River.Due to natural and human factors,the Zoige wetland has been seriously degraded.Existing studies on the Zoige wetland mainly focus on the macro features of the wetland,while the influence of the surrounding faults on the Zoige wetland degradation is rarely studied.This study uses terrain data to analyze the cover change and the water loss caused by the Wqie-Seji fault based on the distributed hydrological model.The simulated water loss demonstrates that the Normalized Difference Vegetation Index(NDVI) is the most important factor for inducing water loss.The fault is also a factor that cannot be neglected,which has caused 33% of the wetland water loss.Therefore,it is of importance to study the influence of the fault on the wetland degradation.  相似文献   

世界遗产地旅游解说系统规划与构建研究——基于安阳殷墟的调查数据   总被引：1，自引：0，他引：1  

罗颖 《地域研究与开发》2011,30(4):103-107,126

遗产地旅游解说系统规划是一项综合而又技术性很强的工程。随着河南世界文化遗产数目的增多,遗产地的旅游解说系统的构建就显得尤为重要,它为游客进行深度的文化解读提供了帮助。采用实地访谈和问卷调查的研究方法,系统全面地介绍了安阳殷墟文化遗产景区解说系统现状,并结合旅游解说系统规划的基本模型所关注的六大要素,提出未来安阳殷墟景区应进行科学系统的理念规划和形象设计、解说系统空间布局规划和分级解说服务系统规划,并注重对游客心理和行为的研究。  相似文献   

北半球夏季中高纬度大气阻塞对北极海冰变化的影响          下载免费PDF全文

肖贻青 黄斌刁一娜  罗德海 《极地研究》2015,27(4):364-378

利用NCEP/NCAR再分析逐日500 h Pa高度场资料,对北半球夏季中高纬度大气阻塞特征进行统计分析,发现大气阻塞活动频率高的地区主要集中在白令海峡区域、鄂霍次克海区域、欧亚大陆区域及格陵兰区域。而通过NSIDC提供的卫星观测资料发现近30年夏季海冰容易减少的区域正好对应阻塞活动北部的高纬度地区。分别通过对以上4个区域有阻塞发生相对没有阻塞发生时的500 h Pa位势高度场、地面温度场、850 h Pa经向瞬变热通量输送和平流输送等异常变化场进行对比分析,结果发现夏季中高纬度阻塞频率的增加对海冰的减少有显著影响,主要体现在阻塞的发生发展可通过增加高纬度地面温度、对极地的热量输送和暖平流输送来加快海冰的融化。这种阻塞引起的热力作用在鄂霍次克海和欧亚大陆区域效果更为显著。  相似文献   

Characteristics of high arsenic groundwater in Hetao Basin, Inner Mongolia, northern China   总被引：2，自引：0，他引：2  

YangChun Zhu  XueYong Zhao  Min Chen  YongQing Luo  Xin Zhou 《寒旱区科学》2015,7(1):0104-0110

It is well known that the Hetao Basin is one of the most seriously arsenic-affected groundwater areas in China. In order to understand the characteristics of high arsenic(As) groundwater in the Basin, a brief overview of arsenic in groundwater follows. High arsenic in the Basin commonly occurs in shallow groundwater and the total arsenic concentrations range from 0.58 to 572 μg/L(average 99.73 μg/L), exceeding the maximum mandated value of 10 μg/L for drinking water in China; As(Ш) is the predominant species. The regional distribution pattern of arsenic in the groundwater increases from south/southeast to north/northwest. Hangjinhouqi and Wuyuan counties are considered as the most seriously affected areas, with high incidences of endemic arsenicosic diseases in the Hetao Basin. High groundwater arsenic correlates with the increase of well depth. Previous studies proposed that groundwater arsenic in the Basin is mainly originated from desorption of some natural solid materials in the sediments, under reducing condition. Generally, reducing condition is believed to be the primary factor for arsenic releasing from the sediment to groundwater in the region. Under inorganic or bacterial processes, Fe2O3 changes to Fe S and arsenic adsorbed to Fe(OH)3 dissolves into groundwater, and As(V) is reduced to As(Ш). Besides, reducing environments, groundwater hydraulic gradients, organic matter, p H, evapotranspiration, and soil texture are presumed to be the predominant factors that control arsenic mobilization.  相似文献   

Estimation of land surface evapotranspiration over the Heihe River basin based on the revised three‐temperature model     

Xinping Luo  Keli Wang  Hao Jiang  Jia Sun  Qingliang Zhu 《水文研究》2012,26(8):1263-1269

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Effect of strong magnetic field on chemical potential and electron capture in magnetar     

高杰  罗志全  刘伟伟  李港 《海洋学报(英文版)》2010,29(9)

The chemical potential of electrons in a strong magnetic field is investigated. It is shown that the magnetic field has only a slight effect on electron chemical potential when B<10¹¹ T, but electron chemical potential will decrease greatly when B>10¹¹ T. The effects of a strong magnetic field on electron capture rates for ⁶⁰Fe are discussed, and the result shows that the electron capture sharply decreases because of the strong magnetic field.  相似文献   

Hydrocarbon accumulation model of the Cretaceous in southern China     

Chen  Bo  Zhang  ChangMin  Luo  MingXia  Lei  QingLiang  Han  DingKun  Zhou  XiaoJun 《中国科学:地球科学(英文版)》2010,52(1):77-87

The Cretaceous in southern China is mainly a set of red and mauve clastic rock, with evaporation layers. For lack of source rock, it has been paid little attention to in the exploration process. With the development of research on hydrocarbon exploration, the masses of Cretaceous reservoirs and shows have been found in recent years. This means that the Cretaceous has great exploration potential. According to the research, authors find that the high-quality reservoir and efficient cap rocks develop in the Cretaceous. At the same time, the Cretaceous and underlying Paleozoic-Early Mesozoic marine strata and overlying Cenozoic nonmarine strata constitute a superimposed basin. Moreover, high-quality source rocks developed in the above-mentioned two sets of strata. In the south, especially in the middle and lower Yangtze region since the Himalayan strong rift was associated with a large number of faults, These faults connect the Cretaceous reservoir and its overlying and underlying source rocks, forming the fault-based and unconformity-based discontinuous source-reservoir-cap accumulation assemblages. Because the Cretaceous has the abundant oil and gas from Paleogene source rocks or Mesozoic-Paleozoic source rocks with secondary hydrocarbon generation ability, three types of reservoirs develop in the Cretaceous: “new-generating and old-reservoiring” reservoirs, “old-generating andnew-reservoiring” reservoirs, and few “self-generating andself-reservoiring” reservoirs. The hydrocarbon enrichment depends on two key factors. Firstly, Cretaceous reservoirs are near to the source kitchens, so its oil and gas source is ample. Secondly, the fault system is well developed, which provides the necessary conducting systems for hydrocarbon accumulation.

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Effects of different operational modes on the flood‐induced turbidity current of a canyon‐shaped reservoir: case study on Liuxihe Reservoir,South China     

Sheng Wang  Xin Qian  Bo‐Ping Han  Lian‐Cong Luo  Rui Ye  Wen Xiong 《水文研究》2013,27(26):4004-4016

Suspended matter is an important indicator of water quality in freshwater systems. The flood‐induced turbidity current plays a dominant role in the seasonal dynamic of suspended matter in the Liuxihe Reservoir (23°45′50″N; 113°46′52″E), a large, stratified reservoir at the Tropic of Cancer in southern China. Field measurements show that loading and distribution of suspended matter in the reservoir differ in typical wet, dry and medium years, as a result of different discharge volumes and water level variation patterns. Using historical data and the practical demand for water supply and flood control, we generalized two feasible reservoir operational modes: flood impounding mode (drawing down the reservoir to a low level before flood events to impound inflow during the flooding season) and moderate level change mode (drawing down the reservoir to a moderate level before flood events, then keeping the level within the flood control level during runoff events). To examine the effects of different operational modes and outlet depths on the reservoir's flood‐induced turbidity current, a numerical simulation model was applied in three types of hydrological conditions. The results show that the mode with moderate drawdown and recharge processes can decrease loading of suspended matter in spring and promote turbidity current release during flood events, and upper withdrawal can improve the effects of turbid water release. We suggest that more attention should be focused on water quality management in the reservoir operation stage, severe artificial water level fluctuation being avoided and selective withdrawal becoming an optional management measure. Copyright © 2012 John Wiley & Sons, Ltd.  相似文献   

A conduit-related genesis of the Lengshuiqing intrusive assemblage (Sichuan,SW China)     

Marian Munteanu  Allan H. Wilson  Yong Yao  Shao-Yong Jiang  Gordon Chunnett  Yaonan Luo  Leonard Mafurutu  Rofhiwa Phadagi 《Journal of Volcanology and Geothermal Research》2010,189(1-2):118-130

Lengshuiqing is part of the late Proterozoic igneous province from the western margin of the Yangtze craton. The Lengshuiqing area comprises five ultramafic–mafic intrusions, emplaced in the late Proterozoic Yanbian Group. The intrusions from Lengshuiqing contain cumulate ultramafic zones (peridotite + olivine pyroxenite), with cumulus olivine and Cr-spinel, and intercumulus pyroxenes, hornblende, phlogopite and plagioclase. Ni–Cu ore (pyrrhotite + pentlandite + chalcopyrite) is hosted in the ultramafic zones. Olivine-free diorite–quartz diorite ± gabbro and granite zones commonly occur above the ultramafic rocks. The genesis of the intrusions (conduit-related accumulation or differentiation from stagnant magma) was investigated. The amount of sulphides in the intrusions from Lengshuiqing is one order of magnitude bigger than the sulphides that can be dissolved by a volume of mafic magma similar with the volume of the intrusions. Most intrusions from Lengshuiqing have bulk composition (peridotite ± diorite ± granite) more magnesian (MgO = 21–22%; Mg# > 78) than the deduced composition of their parental magma (MgO = 9–11%; Mg# = 64–67). This indicates the accumulation of sulphide and mafic silicates from a volume of magma much bigger than the volume of the intrusions, which can be explained by the fractionation from magma ascending through the intrusions to shallower depths. A continuous supply and vent of magma is consistent with the lack of chilled margins, the melting of the wall rocks and the generation of high-temperature mineral assemblages (K-feldspar, diopside, and sillimanite) in the Yanbian Group. The intrusions from Lengshuiqing are seen as microchambers on conduits draining olivine-, Cr-spinel-, and sulphide-bearing mafic magma from a larger staging chamber.  相似文献