英文歌曲与英语学习     

余郑景 《成都信息工程学院学报》1999,(3)

着重说明英文歌曲对英语学习有着不可忽视的作用。具体介绍了通过英语歌曲的学习,可以丰富知识、陶冶情操、增加英文学习兴趣,并且学生可以灵活多样地运用语言,从听、说、读、写、译上有效地克服了英语学习中的困难。  相似文献   

Forestal Arauco experimental research catchments; daily rainfall-runoff for 10 catchments with different forest types in Central-Southern Chile     

Francisco Balocchi  Don A. White  Richard P. Silberstein  Pablo Ramírez de Arellano 《水文研究》2021,35(4):e14047

Forestal Arauco (FA), a global manufacturer of forest products, manages more than 1 million ha of forest plantations and oversees the conservation of more than half a million hectares of native forest and vegetation in Brazil, Argentina and Chile. In 2008, FA responded to local concerns about the effect of plantations on water resources and commenced streamflow monitoring in catchments in the coastal range of central-southern Chile between 35° and 39° of latitude south. This data note presents an overview of daily streamflow and rainfall records for 10 small catchments (18–112 ha) from 2008 to 2018. The catchments are covered by three different forest types, namely native forest (2), pine plantations of different ages (6) and eucalypt plantations (2). All of these catchments share similar metamorphic geology. A 90° V notch weir was built at each catchment outlet and data collected at 5 min interval using a pressure transducer that was calibrated monthly. The dataset is part of a research programme aiming to improve our understanding about the role of forest plantations on water balance at a stand and catchment level. It also includes the rainfall data from these catchments estimated using a combination of local rain gauges and data from the longer term records of the Chilean Directorate of Water. This dataset can be used in hydrological modelling and in a wide range of research questions and water management issues regarding forest plantations in a Mediterranean climate.  相似文献   

Trace elements mineral chemistry of sulfides from the Woxi Au-Sb-W deposit,southern China     

Zhekai Zhou  Kotaro Yonezu  Akira Imai  Thomas Tindell  Huan Li  Jillian Aira Gabo-Ratio 《Resource Geology》2022,72(1):e12279

The Woxi Au-Sb-W deposit is one of the largest polymetallic ore deposits in the Xuefengshan Range, southern China, hosted in low-grade metamorphosed Neoproterozoic volcaniclastic rocks. The orebodies of the deposit are predominantly composed of banded quartz veins, which are strictly controlled by bedding and faults. Petrographic observations and geochemical results are reported on the occurrence of Au and properties of the ore-forming processes for different stages in the deposit. The veins extend vertically up to 2 km without obvious vertical metal zoning. The ore-forming process can be subdivided into four mineralization stages: Pre-ore stage; Early stage (scheelite-quartz stage); Middle stage (pyrite-stibnite-quartz stage); and Late stage (stibnite-quartz sage). Four types of pyrite (Py0, Py1, Py2, and Py3) were identified in the ores and host-rock: Py0 occurs as euhedral grains with voids in the core, ranging in size from 50 to 100 μm and formed mainly in the Pre-ore stage and Early stage; Py1 occurs as subhedral grains. Small grains (around 10 μm) of Py1 form irregularly shaped clusters of variable size ranging from tens to hundreds of μm and mainly formed in the Middle stage; Euhedral-subhedral fine-grained Py2 formed in the Late stage; Minor subhedral fine-grained Py3 was deposited in the Late-stage. Stibnite is widely distributed in the Middle and Late stage ore veins. No systemic difference was recognized in mineralogical features among stibnite formed in different stages. In addition to native gold, the lattice bound Au⁺¹ widely exists in Py1 and Py2 in the deposit, and widespread Py1 is considered as the main Au-bearing mineral with the highest Au contents. Most elements (such as Co, Ni, Cu, As, Sb, Ba, and Pb) are considered to occur as solid solution within the crystal lattice and/or invisible nanoparticles in sulfides minerals. The Co/Ni ratio of most pyrite is lower than 1, suggesting that the metals in the ore-forming fluid are sourced from sedimentary rocks. The coupled behavior between Au and As; Au and Sb suggests that the substitution of As and Sb in pyrite can enhance the incorporation of Au. Variation of trace elements in pyrites of different stages suggests some information on the mineralization processes: Large ion lithophile elements (such as Ba and Pb) are enriched in Py0 indicating that water-rock reaction occurred in the Early stage; Fine-grained Py1 with a heterogeneous distribution of elements suggests fast crystallization of pyrite in the Middle stage.  相似文献   

A Review of the Biogeochemical Cycles of Dissolved Silicon in Rivers   总被引：1，自引：0，他引：1  

Zhang Qianzhu  Tao Zhen  Gao Quanzhou  Ma Zanwen 《地球科学进展》2015,30(1):50-59

The riverine dissolved silicon (DSi) brings environmental information on biogeochemical processes of terrestrial surface, of which the input, transferring, transformation and output are influenced by many factors. Among the weathering of global silicate rocks, 31.53%~64.87% of DSi are intercepted by terrestrial vegetation and only about 12.9% are transferred into rivers. During being transported into ocean, riverine DSi gets impacts from aquatic biological absorption, reverse weathering process and artificial lake effect. The quantity of output is further reduced, which weakens the effect of the oceanic biological pump. According to limited data, the DSi concentration of global rivers has a large variation, ranging from 138 μmol/L to 218μmol/L. It is necessary to quantify contribution rates of influencing factors and establish output models controlled by multiple factors. The δ³⁰Si of riverine DSi ranges from -0.2‰ to 3.4‰. Comparing with the δ³⁰Si of silicate rock, which is about -0.5‰, the fractionation factor is significantly partial to positive from 0.3‰ to 3.9‰. That is because of the occurrence of kinetic fractionation process in river basin including inorganic and organic fractionation. Thus, the key problems, sources and transformation mechanisms of riverine DSi during migration and being transported should be solved in future.  相似文献   

A Study on the Mineralization of the Woxi Au–Sb–W Deposit,Western Hunan,China          下载免费PDF全文

Yi Liang  Guogang Wang  Shengyou Liu  Yuzhen Sun  Yonggang Huang  Kenichi Hoshino 《Resource Geology》2015,65(1):27-38

The Woxi Au–Sb–W deposit in the western Hunan Province, China, is of hydrothermal vein type characterized by a rare mineral assemblage of stibnite, scheelite and native gold, of which gold fineness ranges from 998.6 to 1000. The mineralization sequence observed in the deposit is, from early to late, coarse‐grained pyrite – scheelite – stibnite – Pb–Sb–S minerals – sphalerite (+ cubanite) – fine‐grained pyrite. Native gold may have precipitated with scheelte. Microthermometric and LA–ICP–MS analyses of fluid inclusions in scheelite, quartz associated with scheelite and stibnite and barren quartz clarified that there may be at least three types of hydrothermal fluids during the vein formation in the Woxi deposit. Scheelite and native gold precipitated from the fluid of high temperature and salinity with high concentrations of metal elements, followed by stibnite precipitation. The later fluid of the highest temperature and salinity with low concentrations of the elements yielded the sphalerite mineralization. The latest fluid of low temperature and salinity with low concentrations of the elements is observed mainly in barren quartz. The remarkably high Au/Ag concentration ratios determined in the fluid inclusions in scheelite might be the reason for the extremely high gold fineness of native gold.  相似文献   

Role of different salt marsh plants on metal retention in an urban estuary (Lima estuary,NW Portugal)     

C.M.R. Almeida  Ana P. Mucha  M. Teresa Vasconcelos 《Estuarine, Coastal and Shelf Science》2011

The aim of the present work was to understand the role different salt marsh plants on metal distribution and retention in the Lima River estuary (NW Portugal), which to our knowledge have not been ascertained in this area yet. The knowledge of these differences is an important requirement for the development of appropriate management strategies, and is poorly described for Eurosiberian estuaries, like the one selected. In addition it is important to understand the difference among introduced and native salt marsh plants. In this work, metal levels (Cd, Cr, Cu, Fe, Mn, Ni, Pb and Zn) were surveyed (by atomic absorption spectrometry) in sediments from sites vegetated with Juncus maritimus, Spartina patens, Phragmites australis and Triglochin striata (rhizo-sediments), in non-vegetated sediments and in the different tissues of the plants (roots, rhizomes and aerial shoots). In general, rhizo-sediments had higher metal concentrations than non-vegetated sediments, a feature that seems common to sediments colonized by salt marsh plants of different estuarine areas. All plants concentrated metals, at least Cd, Cu and Zn (and Pb for T. striata) in their belowground structures ([M]_{belowground tissues}/[M]_{non-vegetated sediment} > 1). However, when considered per unit of salt marsh area, the different selected plants played a different role on sediment metal distribution and retention. Triglochin striata retained a significant metal burden in it belowground structures (root plus rhizomes) acting like a possible phyto-stabilizer, whereas P. australis had an higher metal burden in aboveground tissues acting as a possible phyto-extractor. As for J. maritimus and S. patens, metal burden distribution between above and belowground structures depended on the metal, with J. maritimus retaining, for instance, much more Cd and Cu in the aboveground than in the belowground structures. Therefore, the presence of invasive and exotic plants in some areas of the salt marsh may considerably affect metal distribution and retention in the estuarine region.  相似文献   

新疆谢米斯台地区首次发现自然铜矿化   总被引：4，自引：0，他引：4  

王居里  王建其  安芳  杨猛  宋子升  令伟伟 《地球学报》2013,34(3):371-374

首次在新疆谢米斯台地区玄武岩中发现自然铜矿化,伴生自然银。同时在区内酸性次火山岩中发现黄铜矿、斑铜矿矿化。自然铜矿化主要发育于蚀变玄武岩及其中的晚期热液脉中,矿化与绿帘石化、碳酸盐化、葡萄石化、沸石化、硅化等关系密切。初步研究表明,区内自然铜、自然银矿化与火山热液作用有关,属于火山岩型;黄铜矿、斑铜矿矿化属于斑岩型。谢米斯台地区可能存在多种铜矿化类型,有望取得铜矿找矿新突破。  相似文献   

A Review of “In the Shadow of the State: Indigenous Politics,Environmentalism, and Insurgency in Jharkhand,India”     

Ramesh Dhussa 《The Professional geographer》2013,65(2):312-313

In this article, we first replicate and then adapt an existing index of social vulnerability to hazard developed for the United States to a non-U.S. context. We construct indexes for Norwegian municipalities, describe the adjustment process, and compare the replicated and adapted assessments. Our results indicate only a moderate correlation between the replicated and adapted vulnerability indexes and for several municipalities the difference between the indexes is considerable. This demonstrates that context matters and that indexes of vulnerability need to be adapted rather than replicated. To facilitate such adaption processes, we identify three types of accommodation: conceptual, technical, and geographic.  相似文献   

BIOGEOCHEMICAL PROCESSES OF PHOSPHORUS AND SILICON IN SOUTHERN BOHAI SEA SURFACE SEDIMENTS   总被引：3，自引：0，他引：3  

宋金明  罗延馨  吕晓霞  李鹏程 《中国海洋湖沼学报》2002,20(4):378-383

Based on the author’s previously obtained results on P and Si forms in southern Bohai Sea surface sediments,this study maindy foucusing on the controlling factors,existence forms,and biogeo-chemical processes of P and Si showed that the transferable forms of phosphorus in sediments were mainly controlled by the mineralization of organic matters and the reduction of high-valence iron;whereas the transferable forms of silicon were possibly controlled by the dissolution and precipitation as well as bio-chemical processes of living organisms.  相似文献   

恩施硒中毒区土壤高硒的成因:自然硒的证据   总被引：4，自引：0，他引：4  

朱建明  左维  秦海波  冯志刚  郑宝山  苏宏灿 《矿物学报》2008,28(4)

在湖北恩施渔塘坝土壤硒分布的调查过程中,发现不同地段田地土壤中存在异常高硒样品。其硒含量变化范围是346~2018 mg/kg,平均(899±548)mg/kg(n=11),相对于坝内成土基岩和耕作土硒含量0.5 mg/kg与3.5 mg/kg的水平而言,表明这些土壤硒受到了外来源硒的严重污染。扫描电子显微镜的观察表明,这些土壤样品中均有大量晶体状自然硒的出现,其特征类似燃煤型成因的自然硒,证实了上世纪50年代后期恩施当地居民石煤火熏土作肥的耕作方式,并直接导致了田地土壤硒的骤然增加。渔塘坝当地居民在1963年间的硒中毒爆发性流行,乃至恩施地区人畜硒中毒的普遍流行,极可能是人为因素引起。  相似文献