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关键词： Tunnel boring machine   Geoelectrics   Electrical resistivity   Geologic prediction   INDUCED POLARIZATION  

摘要： Tunnel excavation by means of tunnel boring machines (TBMs) is susceptible to unknown changes ahead of the tunnel face. Geophysics. offers a technique called electrical resistivity that can continuously, in real-time, spatially map the formation in front of the TBM. Electrical resistivity has been successfully established for many applications including vadoze zone hydrology, oil/gas location, mineral location and failure detection in geo-structures. Yet it has not been well-established for TBM excavations. This is in part due to the complexity of the TBM tunneling environment and the uncertain influence this environment may have on the success of TBM-integrated-electrical resistivity to predict changes ahead of the tunnel face. One significant uncertainty lies in the interface region that exists around the TBM created during the modification of the virgin formation by a mechanical mixing action of the rotating cutterhead and the injection of additives used to aid in the extraction of the muck and protect the cutting tools from frictional wear. In this study, we investigate the influence of this interface region on TBM-integrated-electrical resistivity for both hard rock and soft ground tunneling conditions through finite element modeling. Regarding the performance of TBM-integrated-electrical resistivity to detect changes ahead of the cutting face, the interface region holds significant influence for both earth pressure balance (EPB) and open mode tunneling conditions. Electrical resistivity for slurry based tunneling is not influenced by the interface region. Simulations suggest that TBM-integrated-electrical resistivity can be sensitive to a formation change that is located up to five diameters in front of the TBM. (C) 2016 Elsevier Ltd. All rights reserved.

关键词： Vitamin D   C3-epimer   mass spectrometry   LC-MS/MS   cord blood   TANDEM MASS-SPECTROMETRY   VITAMIN-D   CIRCULATING 25-HYDROXYVITAMIN-D   3-EPI-25-HYDROXYVITAMIN D-3   INFANTS   ADULTS   ASSAY   SERUM  

摘要： Background The presence of C3-epimer (C-3-epi-25-hydroxyvitamin D) in infant serum may complicate 25-hydroxyvitamin D (25(OH)D) measurement when using liquid chromatography tandem mass spectrometry assays that do not separately measure the epimer. We measured the concentration of C3-epi-25(OH)D in neonatal samples in Western Australian using umbilical cord blood samples and a liquid chromatography tandem mass spectrometry assay that separately quantifies 25(OH)D and C3-epi-25(OH)D. Methods A total of 120 anonymized cord blood samples were analysed using a liquid chromatography tandem mass spectrometry assay that utilizes two CSH fluoro-phenyl columns in series. Chromatography was performed on a Waters Acquity Ultra Performance Liquid system, and quantification was using a Waters Quattro Premier XE mass spectrometer. Results C3-epi-25(OH)D-3 was detected in all umbilical cord blood samples (median 5.2nmol/L, IQR 3.7-6.6nmol/L) and contributed 6.6% (SD 2.6, 95% CI [6.1, 7.1]) of the total 25(OH)D concentration. Mean 25(OH)D-3 measured in cord blood was 79.1nmol/L (SD 22.7nmol/L). A positive relationship (R-2=0.35, P<0.0005) between 25(OH)D-3 levels and C3-epi-25(OH)D-3 was noted in this cohort. No samples contained 25(OH)D-2 or C3-epi-25(OH)D-2. Conclusion C3-epi-25(OH)D-3 is present in all neonatal samples but contributes <10% of the total 25(OH)D concentration which is unlikely to be clinically significant. Liquid chromatography tandem mass spectrometry assays that do not separately quantify C3-epi-25(OH)D-3 from other vitamin D metabolites may potentially overestimate neonatal 25(OH)D levels, but diagnostic misclassification in neonates is unlikely.

关键词： 安全生产   检测检验   作用  

摘要： 我国《安全生产法》等法律法规中对安全生产检测检验工作做出了明确规定,同时认定检测检验工作的开展有助于消除事故问题,为此,当代煤矿企业在可持续发展过程中应提高对检测检验工作的重视程度,且在检测检验工作开展过程中分析在用设备实际运行状况,并判断产品安全性能、产品危险性等,达到最佳的安全事故预防控制效果。本文从安全生产检测检验作用分析入手,并详细阐述了安全生产检测检验工作实施对策。

关键词： 痕迹检验技术   刑事技术体系   地位   作用  

摘要： 痕迹检验技术是一种常用的侦查技术,现本文主要对其在刑事技术体系中的地位及作用进行研究,主要目的为日后公安机关侦查工作提供有效借鉴和参考。

关键词： 微生物形态学   检验   感染性疾病  

摘要： 微生物形态学检验是临床中诊断感染性疾病的重要方式,通过微生物形态学检验了解病原菌的特点,从而针对性的采取治疗方案,为临床感染性疾病的治疗提供了重要的依据。本文主要对微生物形态学检验在感染性疾病诊断中的作用进行探讨,现综述如下。

关键词： 风险管理   进出口产品   检验检疫  

摘要： 自2008年的美国次贷危机以来，全球各主要经济体深陷经济衰退泥团，国际贸易下滑颓势不减，各国为保护自身产业，减轻国内经济压力，频频使出贸易保护利器，运用技术性壁垒等一系列贸易保护措施对竞争对手产品进行制裁，导致发展中国家尤其是涉及中国的进出口产品质量安全问题不断增多，进出口产品质量安全也越来越受到全社会的关注，使得检验检疫检验监管的风险问题越来越多的被提及。如何进一步提高检验监管的针对性、有效性，切实解决既要“管得住”，又要“放得快”的现实需求，及时化解存在于检验检疫执法把关中存在的各种风险成为当前检验检疫亟待研究、解决的问题。

关键词： 动植物   检验检疫   重要性   作用  

摘要： 本文分析总结了动植物检验检疫的起源、发展过程以及国内外关于动植物检验检疫的主要相关法律法规及其制定的背景,探讨了动植物检验检疫在实践中的必要性和重要作用。

关键词： 种子质量   检验   技术  

摘要： 种子质量好坏，不仅影响了农作物生长态势，而且关乎农作物品质及农产品安全。相关部门要在种子生产、加工和销售关节，安排专业检验人员对种子质量进行严格检验，以良种实现农作物增产。本文主要分析种子质量检验作用及方法，为农作物种植及生产奠定良好的基础。