蛭石尾砂在燃煤固硫除尘中的利用

在对新疆且干布拉克蛭石矿尾矿进行矿物学研究的基础上，进行了高温膨胀实验、结果表明，蛭石尾砂的膨胀倍数因粒度的增大、时间的延长而提高，较为理想的膨胀温度在950～1050℃之间，利用碳酸钙为固硫剂、膨胀土为粘结剂，蛭石尾矿为膨胀添加剂对肥城烟煤进行高温燃煤固硫实验。结果表明，蛭石尾砂能较大幅度地提高肥城烟煤的固硫率，经XRD、SEM和EDX等分析表明，燃煤灰渣的主要固硫物相为硫酸钙，且因燃烧条件、添加剂和燃煤种类的差异而以不同的形态存在。蛭石尾砂对燃煤固硫促进机理可解释为营造型煤内部氧化气氛，抑制新物相硫酸钙的分解。     

地电观测系统的维护保养及故障的判断与排除

叙述了地电观测系统、外线路的维护、仪器故障的判断与排除,以及辅助设备的维护与保养,以此来提高观测资料的质量。     

形变数字化仪器故障分析

通过对山东省形变仪器故障的总结和分析,提供了形变仪器故障排除的经验,为台站运行维护提供参考。     

Mountain pastures, environmental degradation, and landscape remediation: The example of a Mediterranean policy initiative

Since the 1950s the Spanish Mediterranean mountains have undergone a process of population decline, abandonment of land by farmers, and a reduction in livestock pressure. These changes have involved pasture loss as a result of the spread of scrub and an increase in the incidence of fires. To avoid these negative outcomes the regional administration of La Rioja (Spain) has implemented scrub clearance programs. Between 1986 and 2005 a total of 23,668 ha were cleared, particularly on abandoned fields where the processes of vegetation succession had led to the dominance of Genista scorpius and Cistus laurifolius. Pasture regeneration as a result of scrub clearing of areas dominated by G. scorpius has resulted in a productivity rise from 6666 to 12,983 Mj/ha/year, whereas productivity of areas dominated by C. laurifolius has risen from 2435 to 9741 Mj/ha/year. The clearing of scrub needs to be recognized as a significant factor contributing to the control of fire. Scrub clearing has had positive results in La Rioja, leading to a reduced incidence of fires in recent years. Between 1996 and 2005 only 155 ha/year was burnt, compared with 1541 ha/year over the period from 1976 to 1985. Scrub clearing appears to be an appropriate means of management in marginal mountainous areas without the need for large investments of time and money.     

Analysis of land degradation processes on a tiger bush plateau in South West Niger using MODIS and LANDSAT TM/ETM+ data

Remote sensing digital image analysis has been applied to monitor land clearing and degradation processes on a plateau covered by tiger bush near Niamey in South West Niger, where signs of severe landscape degradation due to fuelwood supply have been observed in the last decades. A MODIS NDVI dataset (2000–2015) and five LANDSAT images (1986–2012) were used to identify spatial and temporal dynamics and to emphasize areas of greater degradation. The study indicates that the land clearing found by previous investigations in the second part of the 20^th century is still ongoing, with a decreasing trend of MODIS NDVI values recorded in the period 2000–2015. This trend appeared to be linked to an increase in bare soil areas that was demonstrated by analysis of LANDSAT SAVI images. The investigation also indicated that rates of degradation are stronger in more deteriorated areas like those located nearer Niamey; degradation patterns also tend to increase from the inner areas to the edges of the plateau. These results attest to the urgency to develop effective environmental preservation policies and find alternative solutions for domestic energy supply.     

涞源龙门金多金属矿普查绿色勘查实践

河北省涞源县龙门金多金属矿普查工作,贯彻绿色勘查理念,对槽探工程、老硐清理、钻探工程按《绿色勘查指南》进行了专项设计并付诸实施。槽探工程施工挖掘的腐植土和碎石就近分开堆放并遮盖,待项目验收合格后,回填腐植土和碎石,最后平整并绿化;老硐清理出的碎石选择离硐口较近的相对平坦的地方堆放,并做好防护工作,最后覆土绿化;钻进工程采用清水和环保泥浆做冲洗液,金刚石单管和绳索取心钻进,提高了效率,减少了对地质环境的影响。机台建设占地少,施工过程中避免油污等的外溢,项目竣工验收后地貌恢复采用植草、自然恢复等绿化方法。绿色勘查充分贯彻了绿水青山就是金山银山的绿色发展理念。     

The geo-politics of Brexit,the euro and the City of London

In this review, we call for more engagement with the geo-political dimension of the finance economy that epitomises the 21st-century capitalist order within the European Union. Using the example of financial clearing and settlement, key processes in global trade and finance mechanisms in which London leads the world, we discuss the entangled political and economic dimensions in the shadow of Brexit to come, and its potential impact on the City’s complex financial ecosystem. The aim here is not to consult the crystal ball and predict London’s future as a financial centre. Yet, euro clearing is of geo-political relevance: if the UK leaves the EU, euro clearing would be taking place outside of the ECB’s regulatory space of intervention. This can become highly problematic, as the nominal euro sums involved in a major crisis are immense. We believe that these processes illustrate the pressing need to engage with finance’s geo-economics and geo-politics in more depth, both empirically and conceptually.     

Mangrove fish: a comparison of community structure between forested and cleared habitats

The fish communities of mangrove and cleared sites were investigated in Gazi Bay, Kenya. Five forested sites were compared with paired sites that had been cleared of mangroves by human activity. Forested sites included plantations and natural stands of Sonneratia alba and natural Rhizophora mucronata stands. Two methods of stake netting were used to take quantitative samples; method one used a single 100-m-long, 18-mm mesh net, method two used paired 24-m-long, 1-mm mesh nets—samples were taken during seven different months in 2002. Mean abundances of fish found in mangrove and cleared sites, respectively, were 0.004 m⁻² and 0.014 m⁻² (method 1) and 0.21 m⁻² and 0.25 m⁻² (method 2). Thirty species were sampled, 12 of which were found exclusively in mangrove habitats and 10 of which were limited to cleared sites. The most abundant species in mangrove plots was Atherina afra (although it was only found in two, large catches); the most abundant in cleared plots was Gerres oyena (found frequently). Mean abundance (using data pooled for all sites) was significantly higher in cleared, compared with forested, sites, and multivariate analysis showed significantly different community structures in the two habitat types. There was large variation in catch rates between dates and sites, with one forested site recording no catches at all. These results do not support the predator refuge hypothesis (which predicts higher abundance of juvenile fish inside mangroves). The low abundance of fish recorded in the mangrove sites may have been due to site-specific factors determining fish abundance within mangrove forests, to the sampling techniques used or to relatively high turbidities at these sites.     

The ecohydrological imprint of deforestation in the semiarid Chaco: insights from the last forest remnants of a highly cultivated landscape

The semiarid Chaco plains present one of the highest rates of forest clearing and agricultural expansion of the world. In other semiarid plains, such massive vegetation replacements initiated a groundwater recharge and salt mobilization process that, after decades, raised regional water tables and salts to the surface, degrading agricultural and natural ecosystems. Indirect evidence suggests that this process (known as dryland salinity) began in the Chaco plains. Multiple approaches (deep soil profiles, geoelectric surveys and monitoring of groundwater salinity, level and isotopic composition) were combined to assess the dryland salinity status in one of the oldest and most active agricultural hotspots of the region, where isolated forest remnants occupy an extremely flat cultivated matrix. Full vadose moisture and chloride profiles from paired agriculture‐forest stands (17 profiles, six sites) revealed the following: a generalized onset of deep drainage with cultivation (32 to >87 mm year^?1), full leaching of native chloride pools (13.7 ± 2.5 kg m^?2) down to the water table after >40 years following clearing and differential groundwater table rises (0.7 to 2 m shallower water tables under agriculture than under neighbouring forests). Continuous level monitoring showed abrupt water table rises under annual crops (up to 2.6 m in 15 days) not seen under forests or pastures. Varying deep drainage rates and groundwater isotopic composition under agricultural plots suggest that these pulses are strongly modulated by crop choices and sequences. In contrast to other dryland salinity‐affected areas of the world, forest remnants in the study area (10–20% of the area) are not only surviving the observed hydrological shifts but also sustaining active salty groundwater transpirative discharge, as evidenced by continuous water table records. The overall impact of these forest remnants on lowering neighbouring water tables would be limited by the low hydraulic conductivity of the sediments. As highly cultivated areas of the Chaco evolve to new hydrological conditions of shallower saline water tables, innovative crop rotations that minimize recharge, enhance transpirative discharge and tolerate salinity will be needed. Copyright © 2016 John Wiley & Sons, Ltd.     

旋挖机械清渣在嵌岩扩底桩中的应用

嵌岩扩底桩是一种端承型基桩,桩底沉渣的厚度直接影响基桩的承载力。某工程设计为嵌岩扩底桩,采用了旋挖机械清渣施工方法。实践证明,机械清渣能减少施工工序,提高施工效率,保证桩的施工质量。