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超声波萃取-高效液相色谱法在海洋沉积物样品多环芳烃分析中的运用 总被引：6，自引：0，他引：6
建立用超声波萃取-高效液相色谱法同时检测海洋沉积物中16种优先监控的多环芳烃(PAH s)的方法。本方法采用丙酮作为萃取溶剂,在超声波作用下萃取出泥样中的PAH s,萃取液经浓缩后直接进行高效液相色谱分析。经对色谱条件和萃取条件进行优化后,各PAH组分的线性范围为1~500 ng之间,相关系数0.9921~0.999,检出限0.1~4.6 ng,达到海洋沉积物PAH s的检测要求。运用本法对粤东大规模增养殖区柘林湾表层沉积物PAH s进行检测,各PAH组分加标回收率为69.2%~108%,总平均达89.2%,相对标准偏差为0.5%~10.3%。本方法只需要萃取、浓缩和定容三个步骤,具有简便、迅速、高效、分析成本低的特点。 相似文献
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The mechanical and hydraulic properties of unsaturated clay under nonisothermal conditions have practical implications in geotechnical engineering applications such as geothermal energy harvest, landfill cover design, and nuclear waste disposal facilities. The water menisci among clay particles impact the mechanical and hydraulic properties of unsaturated clay. Molecular dynamics (MD) modeling has been proven to be an effective method in investigating clay structures and their hydromechanical behavior at the atomic scale. In this study, we examine the impact of temperature increase on the capillary force and capillary pressure of the partially saturated clay-water system through high-performance computing. The water meniscus formed between two parallel clay particles is studied via a full-scale MD modeling at different elevated temperatures. The numerical results have shown that the temperature increase impacts the capillary force, capillary pressure, and contact angle at the atomic scale. The capillary force on the clay particle obtained from MD simulations is also compared with the results from the macroscopic theory. The full-scale MD simulation of the partially saturated clay-water system can not only provide a fundamental understanding of the impact of temperature on the interface physics of such system at the atomic scale, but also has practical implication in formulating physics-based multiscale models for unsaturated soils by providing interface physical properties of such materials directly through high-performance computing. 相似文献
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目的：建立中药舒心片中丹酚酸B含量的测定方法。方法：采用高效液相色谱法（HPLC）测定舒心片中丹酚酸B的含量,色谱柱为Agilent TC-C18（2）色谱柱（4.6 mm×250 mm,5 μm）,以乙腈-0.1%的磷酸溶液（25∶75）为流动相;检测波长为286 nm;柱温为25℃;流速为1.0 ml/min。结果：供试品和对照品溶液中丹酚酸B与他峰分离度良好;在0.050～1.642 μg之间丹酚酸B呈良好线性关系,R=0.9993,丹酚酸B平均加样回收率为97.58%,RSD=0.25%。结论：经方法学验证,本法可用于舒心片的质量控制。 相似文献
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针对内蒙古兴和县曹四夭钼矿区构造发育,地层坚硬、岩心破碎,以及钻孔缩径、漏失、坍塌、掉块等复杂情况,总结了该矿区“硬、脆、碎”复杂地层绳索取心深孔钻探施工技术经验,从钻孔结构、泥浆配置和冲洗液选取以及钻探设备、新型SYZX75 2（77）型绳索取心液动锤钻具等方面采取措施,解决了破碎漏失、坍塌掉块及坚硬“打滑”地层的难题。着重阐述了高强度快失水堵漏技术试验,改善了复杂地层的深孔钻进环境,提高了钻探生产效率,保证了钻孔的安全终孔。 相似文献
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境外钻探施工不但有施工技术方面的难题,更重要的是会遇到境外的施工环境、语言等诸多让人担忧让人却步的从未接触过的问题。介绍了在老挝巴勉岩金矿进行钻探施工遇到的各种难题及解决办法。 相似文献
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在印尼塔里阿布铁矿项目岩心钻探施工中,其地层既具有泥岩、页岩、粘土岩的遇水膨胀、坍塌,又有凝灰岩、火山灰岩的遇水溶解及硅化石英岩的“打滑”,以及粉状铁矿取心难的特点。易出现卡钻、粘钻等孔内事故。通过大胆的探索,形成了针对该地区岩心钻探施工的一套施工工艺,取得了良好的钻探技术效果。详细介绍了印尼塔里阿布岛铁矿项目岩心钻探施工技术。 相似文献
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通过ＨＺ３０８多功能取心钻具有蚀变岩型和石英脉型金矿地层的应用，提出了防止底喷分流式钻头堵心、减少其损耗的措施。 相似文献
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Jia Liu Dustin Feld Jochen Garcke Thomas Soddemann Peiyuan Pan 《International Journal of Digital Earth》2016,9(8):748-765
Quantitative remote sensing retrieval algorithms help understanding the dynamic aspects of Digital Earth. However, the Big Data and complex models in Digital Earth pose grand challenges for computation infrastructures. In this article, taking the aerosol optical depth (AOD) retrieval as a study case, we exploit parallel computing methods for high efficient geophysical parameter retrieval. We present an efficient geocomputation workflow for the AOD calculation from the Moderate Resolution Imaging Spectroradiometer (MODIS) satellite data. According to their individual potential for parallelization, several procedures were adapted and implemented for a successful parallel execution on multi-core processors and Graphics Processing Units (GPUs). The benchmarks in this paper validate the high parallel performance of the retrieval workflow with speedups of up to 5.x on a multi-core processor with 8 threads and 43.x on a GPU. To specifically address the time-consuming model retrieval part, hybrid parallel patterns which combine the multi-core processor’s and the GPU’s compute power were implemented with static and dynamic workload distributions and evaluated on two systems with different CPU–GPU configurations. It is shown that only the dynamic hybrid implementation leads to a greatly enhanced overall exploitation of the heterogeneous hardware environment in varying circumstances. 相似文献
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在陇南紫金李坝金矿钻探施工中遇强水敏性、破碎、复杂地层,普通绳索取心钻具岩心采取率低,平均采取率86.5%,回次进尺少,多在1 m以下,最小回次进尺只有20～30 cm,钻进效率低,平均台班进尺约5 m。通过使用SYZX96型绳索取心液动锤,钻进效率明显提升,平均岩心采取率提高8%,平均回次进尺提高50%,平均台月效率提高17.5%,纯钻时间增加到了60%左右。共完成6个钻孔,进尺2488 m,其中2个钻孔采用SYZX96型绳索取心液动锤,效果明显。总结出适合强水敏性、破碎、复杂地层绳索取心液动锤的使用经验,为类似地层钻探施工提供技术借鉴。 相似文献