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Mauskopf PD Ade PA de Bernardis P Bock JJ Borrill J Boscaleri A Crill BP DeGasperis G De Troia G Farese P Ferreira PG Ganga K Giacometti M Hanany S Hristov VV Iacoangeli A Jaffe AH Lange AE Lee AT Masi S Melchiorri A Melchiorri F Miglio L Montroy T Netterfield CB Pascale E Piacentini F Richards PL Romeo G Ruhl JE Scannapieco E Scaramuzzi F Stompor R Vittorio N 《The Astrophysical journal》2000,536(2):L59-L62
We describe a measurement of the angular power spectrum of anisotropies in the cosmic microwave background (CMB) at scales of 0&fdg;3 to 5 degrees from the North American test flight of the Boomerang experiment. Boomerang is a balloon-borne telescope with a bolometric receiver designed to map CMB anisotropies on a long-duration balloon flight. During a 6 hr test flight of a prototype system in 1997, we mapped more than 200 deg(2) at high Galactic latitudes in two bands centered at 90 and 150 GHz with a resolution of 26&arcmin; and 16&farcm;5 FWHM, respectively. Analysis of the maps gives a power spectrum with a peak at angular scales of 1 degrees with an amplitude 70 μK(CMB). 相似文献
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土耳其卡赞碱矿钻井项目主要利用高精度中靶技术使定向水平井与垂直井在碱层中对接后进行水溶开采的方法。该项目通过长期大量的钻井工作,在已有的钻井技术与地质条件基础上,改进完善了与地层相适应的钻井技术,建立了矿区三维地质模型,设计应用了水平分支对接井,优化了钻井轨迹设计,建立起非矿层与矿层的基准物探测井响应曲线,探索出矿区地层致斜机理及相应钻井防斜措施,研究并应用了各种井底钻具组合与设备,采用了提高水平钻井轨迹控制精度的技术方法。上述多种水溶采矿钻井技术创新措施的应用,提高了矿山规划能力、降低了施工成本、提高了资源回采率、缩短了施工工期、降低了劳动强度、提高了钻进效率、减少了施工用地以及对环境的破坏。可为天然碱矿及可溶性矿产的整体矿山规划,以及钻井水溶采矿技术的提高提供借鉴。 相似文献
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土耳其天然碱溶采钻井项目包括ETI SODA开发合同一~六期和KAZAN SODA开发合同一~三期,共成功实施溶采井组200余组。海外钻井工程涉及的影响因素较多,除常规的钻井工程技术问题外,还需要适应当地的政治、法律、风俗、汇率、海运、关税等问题。项目部在实施过程中根据海外钻井工程特点以及现场施工环境,加强项目人员、设备材料、现场作业、安全及风险等方面的管理,发挥指导、管理、控制作用,降低工程风险,提高收益,确保项目顺利完工。本文就土耳其天然碱溶采对接井钻井项目人员组织管理、设备器具管理、现场作业程序管理、HSE管理及风险管理进行了介绍,总结了一些海外钻井项目管理经验。 相似文献
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SmartMag定向中靶系统由安装于钻头后部的磁信标、安装于靶井中的磁信号采集探管、地表接口箱和磁信号解析软件等组成,它通过测量磁信标在钻进过程中所产生的动态磁场,从而解析出钻头和靶点之间的相对位置参量,最终引导钻进进入靶区或避让靶区。介绍了SmartMag定向中靶系统在土耳其贝帕扎里天然碱矿采集卤钻井工程中的工业性入井试验的应用情况。该系统在前期研发中打下了良好的技术基础,因此在首次入井试验中就取得了一次中靶的良好效果。 相似文献
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This study assessed numerous histological parameters as markers of health status in mussels (Mytilus spp.) collected from several locations along a contamination gradient on the River Tamar and two coastal sites on the north and south coast of Cornwall, UK. Twenty-seven health parameters were assessed including the presence of pathogens, inflammatory lesions, non-specific pathologies and reproductive condition. Logistic regression showed that reproductive condition and inflammatory lesions showed changes indicative of a contamination gradient response. Mussel populations further upstream within the Tamar were relatively less developed compared to mussels situated downstream in the estuary. Compared to coastal locations, mussels sampled within the Tamar also exhibited a higher prevalence of inflammatory lesions that increased at locations situated furthest upstream. Similarly, levels of lipofuscin within the kidney epithelium were highest in mussels sampled within the estuary and Whitsand Bay compared to Trebarwith Strand. The most prevalent pathogens observed during this survey included Rickettsia/Chlamydia-like organisms (R/CLO), gill ciliates including Ancistrum mytili, the copepod Mytilicola intestinalis, Ciliophora-like organisms and Marteilia sp. Marteilia sp. was observed in 31% of the mussels sampled from the Cremyll Ferry site. Generally, the range and prevalence of pathogens was highest from the two estuarine locations at Cremyll Ferry and Wilcove. No significant differences were observed between estuarine sampling sites and Whitsand Bay with respect to median epithelial cell height of digestive tubules, however mussels from Trebarwith Strand did exhibit a reduced median epithelial cell height compared to mussels sampled from other sampling sites. Species genotyping was also undertaken during this study in order to consider any histological differences in relation to species. Results are discussed in relation to histopathology health parameters and biological effects monitoring. 相似文献
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The viviparous blenny (Zoarces viviparus), also known as eelpout, is considered a suitable biomonitor for use in European estuarine and coastal waters. We have previously shown that Z. viviparus from the industrialised Tyne estuary (UK) display certain histopathologies (e.g., ovotestis and hepatic nuclear and cellular pleomorphism), which are associated with contaminant exposure [Mar. Environ. Res. 55 (2003) 137]. Furthermore, the prevalence of these pathologies was higher than in fish collected from a less contaminated reference site (the Alde estuary, UK). Here, tissue samples were collected from Z. viviparus from the Tyne and Alde estuaries (in the spring and autumn) and analysed for DNA adducts using the (32)P-postlabelling assay and for histopathology. Z. viviparus caught from the Tyne during the spring (56.4+/-18.5 adducts per 10(8) nucleotides) and autumn (63.1+/-7.5 adducts per 10(8) nucleotides) exhibited patterns of DNA adducts which indicated exposure to a complex mixture of genotoxins. In contrast, levels of DNA adducts in Z. viviparus from Alde estuary were significantly lower during both sampling periods. Histopathological changes to the gonads included intersex (ovotestis) and germ cell apoptosis (detected via the TUNEL assay) in male fish captured from the Tyne estuary. Further studies on the use of germ cell apoptotic rate at different estuarine sites are required if it is to be used as a reproductive biomarker of contaminant exposure in male fish. 相似文献