电子计算机在储量计算中的应用     

喻铁阶  D.T.O''brain  A.Weiss 《地质与勘探》1973,(1)

在电子计算机上按常规的方法计算储量,比手工操作的效率要高得多.除此以外,由于采用了电子计算机,还形成了一种新的"矿量动态平衡法(mineralization inventory)",这是手工操作所难于做到的.如果使用得当,"矿量动态平衡法"不但能准确地完成常规方法的全部工作,而且还可以同时算出矿山生产成本和作出全面的资源评价.我们知道,适当的矿石工业品位指标只有在估算了生产成本之后才能选定,  相似文献   

日本中部奥拉层状岩浆杂岩中的铬尖晶石     

Taka.  T. 周美付 《地质科学译丛》1989,(2):6-15

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矿物共生组合及其实际意义     

晋燧  T.M.卡伊科娃 《地质与勘探》1975,(4)

最近15～20年间,从事矿石物质成分研究的地质和矿物工作者,对矿物共生组合问题产生了特殊的兴趣.这是因为,研究矿物共生组合,是揭示成矿地球化学条件的基础,是探讨矿床成因的一个重要方面,它对发展成矿理论起着重要作用.此外,阐明矿物共生组合在时间和空间上的关系和规律变化,还有一定实用价值.在详细研究各类矿床矿石成分的基础上,能够获得矿物共生组合方面的大量材料,这就大大提高了各种结论的可信程度.  相似文献   

Copper speciation survey from UK marinas, harbours and estuaries     

Jones B  Bolam T 《Marine pollution bulletin》2007,54(8):1127-1138

The use of copper in antifouling paints has increased in the UK in the last 20 years as TBT and several other organic biocides have been phased out. To assess the probable impact of copper on estuarine systems a survey was undertaken to measure the different fractions of copper present in the water column at current usage. The different fractions measured were; labile copper, (LCu) considered as both the free copper ions and inorganically bound copper, the total dissolved copper (TDCu) present, and the difference between them taken as the organically bound likely non-toxic copper fraction. The survey considered sites with different levels of boat use, namely marinas, harbours and estuaries, differing physical parameters of suspended and dissolved organic matter, different seasons of the year and different depths in the water column all of which control speciation behaviour. Suspended particulate matter (SPM) values were measured at all sites and increased from West to East coast locations (5.7-34.4 mg/l). Dissolved organic matter (DOM) values ranged from 0.58 to 2.2mg/l C. The total dissolved copper concentrations ranged from 0.30 to 6.68 microg/l, with labile fraction ranging from 0.02 to 2.69 microg/l, and most labile copper concentrations below 1 microg/l. None of the yearly mean copper measurements exceeded the 76/464/EEC EQS of 5 microg/l. Of the 306 measurements, only one dissolved copper value in one season was above 5 microg/l. This ratio of labile to total copper was between 10 and 30%. The results from this survey suggest that if toxicity of copper is due to the labile fraction then using the total dissolved copper concentrations as an indicator of impact overestimate the risk by a factor of four times.  相似文献   

Effects of ulvoid (Ulva spp.) accumulation on the structure and function of eelgrass (Zostera marina L.) bed     

Sugimoto K  Hiraoka K  Ohta S  Niimura Y  Terawaki T  Okada M 《Marine pollution bulletin》2007,54(10):1582-1585

The objective of this study is to clarify the effect of ulvoid (Ulva spp.) accumulation on the structure and function of an eelgrass bed by the coast of Iwakuni, Seto Inland Sea, Japan. We monitored eelgrass shoot density and volume of ulvoid accumulation in the study site and evaluated effects of the accumulated ulvoid canopy on the percent survival, seedling density, growth rates, photosynthetic photon flux density (PPFD) and carbon contents of eelgrass. Eelgrass shoot density decreased by the accumulation of ulvoid. Also, seedling density decreased by the increase in the ulvoid volumes. Shoot density, seedling density and leaf elongation were negatively correlated with ulvoid volume. Carbon contents in eelgrass decreased by the accumulation of ulvoid (canopy height: 25cm). These results suggest that accumulation of ulvoid bloom has significant negative impacts on the structure and function of eelgrass bed, i.e. decreases in vegetative shoot density, seedling density, shoot height and growth rate.  相似文献   

Anthropogenic contributions to heavy metal distributions in the surface sediments of Masan Bay, Korea   总被引：1，自引：0，他引：1  

Hyun S  Lee CH  Lee T  Choi JW 《Marine pollution bulletin》2007,54(7):1059-1068

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Heavy metal contamination in western Xiamen Bay sediments and its vicinity, China   总被引：5，自引：0，他引：5  

Zhang L  Ye X  Feng H  Jing Y  Ouyang T  Yu X  Liang R  Gao C  Chen W 《Marine pollution bulletin》2007,54(7):974-982

Concentrations of selected heavy metals (Cu, Pb, Zn, Cd, Cr, Ni and Fe) in surface sediments from nine sites in western Xiamen Bay and its vicinity were studied in order to understand current metal contamination due to urbanization and economic development in Xiamen, China. The sediment samples were collected in December 2004 and July 2005 respectively in order to examine temporal variations. In this study, we found that heavy metal concentrations in surface sediments sampled in the western Xiamen Bay and adjacent Maluan Bay and Yuandang Lagoon varied from 19 to 97mg kg(-1) for Cu, 45 to 60mg kg(-1) for Pb, 65 to 223mg kg(-1) for Zn, 0.11 to 1.01mg kg(-1) for Cd, 37 to 134mg kg(-1) for Cr, 25 to 65mg kg(-1) for Ni and 3.08 to 4.81% for Fe. Although all metal concentrations in sediments meets Chinese National Standard Criteria for Marine Sediment Quality, both metal enrichment factors (EF) and geoaccumulation index (I(geo)) show that Pb contamination exists in the entire study area and contamination of other metals are also present in some locations depending on the sources, of which sewage outlets and commercial ports are the main sources of contaminants to the area. This study shows that using the sediment quality standard criteria only to assess sediments cannot properly reflect sediment contamination. A multiple approaches should be applied for the sediment quality assessment.  相似文献   

Plastic debris as nesting material in a Kittiwake-(Rissa tridactyla)-colony at the Jammerbugt, Northwest Denmark     

Hartwig E  Clemens T  Heckroth M 《Marine pollution bulletin》2007,54(5):595-597

This paper continues the investigations of Clemens and Hartwig from 1992 on the proportion of garbage used as nesting material in the Kittiwake colony at Bulbjerg in the Jammerbugt in Northwest Denmark. Whereas in the year 1992 plastic garbage items were included in 39.3% of 466 Kittiwake nests in the Bulbjerg colony, in 2005 57.2% of 311 nests contained plastic debris. Although it has been forbidden to dispose of plastic garbage into the marine environment since the implementation of the MARPOL 73/78-Agreement/Annex V (Regulation for the Prevention of Pollution by Ship Waste) of 1989 and especially since the declaration of the North Sea as a MARPOL-Special Area for garbage in 1991, the pollution of the oceans and the North Sea is still an ubiquitous problem, particularly with regard to plastic waste. Plastic waste is presumably not used preferentially for nest-building, but in the context of available nesting material in the waters surrounding the breeding colony. Therefore the share of garbage parts in nests of certain species of birds is an indicator of the amount of waste in the natural environment in the vicinity of their breeding site.  相似文献   

The ecological quality status of the Bay of Seine and the Seine estuary: use of biotic indices     

Dauvin JC  Ruellet T  Desroy N  Janson AL 《Marine pollution bulletin》2007,55(1-6):241-257

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A multivariate index based on the seagrass Posidonia oceanica (POMI) to assess ecological status of coastal waters under the water framework directive (WFD)     

Romero J  Martínez-Crego B  Alcoverro T  Pérez M 《Marine pollution bulletin》2007,55(1-6):196-204

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