Laboratory application of laser grain-size analyzer in determining suspended sediment concentration     

Xiao Liu  Xiuli Feng  Jie Liu  Lin Lin 《中国海洋大学学报(英文版)》2014,13(3):375-380

Suspended sediment concentration （SSC） is an important parameter in marine sedimentology. With the development of technology, many acoustic and optical devices, such as the Laser In-Situ Scattering and Transmissometry, have been designed to meas-ure in situ SSC and grain size distribution. But due to fund or other restrictions, many experiments were only conducted in laboratory, using an indoor laser grain-size analyzer and gravimetric method to measure grain size distribution and concentration, respectively. In this study the laboratory experiment is simplified by omitting the tiring step of gravimetric method. The connections between SSC and other parameters （obscuration, D50 and sorting index） were investigated based on 124 surface sediment samples collected from different offshore areas. A new method is developed for determining SSC in laboratory using a laser grain-size analyzer.  相似文献   

元素俘获能谱测井标准谱测量与模拟(英文)   总被引：3，自引：1，他引：2  

武宏亮  李宁  兰长林  孔祥忠  柴华 《应用地球物理》2013,10(1):109-116

为了解决目前元素俘获能谱测井解释中,根据原始测量谱难以准确获得各个元素产额的困难,本文建立了一套先进的测量元素俘获伽马能谱实验方法,首次获得了硅、钙和铁等10种元素的标准俘获伽马能谱;并利用蒙托卡罗方法在同样条件下模拟得到了上述10种元素的标准模拟俘获伽马能谱。将这两种方式获得的元素标准俘获伽马能谱与国际原子能机构核数据中心数据进行对比分析,从中确定了可用于实际元素俘获能谱测井解谱计算的硅、钙和铁等10种元素的俘获伽马能谱。这一结果有效解决了元素俘获能谱测井资料处理过程中由原始测量谱到各元素产额转换过程中的关键技术难点,可有效提高元素产额的计算精度。  相似文献   

应用高频红外碳硫仪测定农用地土壤样品中有机质含量     

殷陶刚  窦向丽  张旺强  和振云 《岩矿测试》2020,39(4):631-638

应用高频红外碳硫仪测定农用地土壤样品中的有机质，避免了传统方法中的试样液体转化环节，测定效率高，但存在土壤样品电磁感应低和基体影响较大等问题。本文通过实验优化了样品称样量、助熔剂铁和钨的添加量等测定条件，结果表明：当样品称样量为0.05g、助熔剂铁添加量为0.40g、钨添加量为1.50g时，有机质测定效果最佳。通过土壤标准物质进行验证，方法检出限为0.003%，相对标准偏差（RSD，n=7）小于4%，测定值与认定值的相对误差小于5%，且不同分析人员的测定结果间没有显著差异。采用本法与重铬酸钾容量法对甘肃省农用地土壤样品进行测定，两种方法测定值的绝对误差为-0.25%~0.28%，测定结果之间呈极显著线性正相关（R²=0.9736），表明两种方法的一致性很好。本方法的检出限、精密度、准确度均满足农用地土壤样品有机质测定要求。  相似文献   

日本本州东海岸附近海域9．0级地震前地应力异常     

张蕙  张道义 《地震地磁观测与研究》2012,33(3):10-13

2011年3月¨目日本本州东海岸附近海域9．0级特大地震发生前,中国辐射防护研究院地震台PYL-3型高精度地应力仪记录的地震前,应力短期异常、临震异常情况,并作初步分析与研究。  相似文献   

RG-BS智能数字测汞仪与XG-5Z塞曼测汞仪同步观测对比分析     

杨志坚  李朝明 《地震地磁观测与研究》2012,33(5):193-196

利用RG-BS型智能数字测汞仪,与XG-5Z型塞曼测汞仪对下关温泉水汞含量进行为期1年的同步观测实验,从仪器的整体结构、工作原理、技术指标参数以及同步观测结果等方面进行对比,认为两台仪器一致性比较好,能够正确反映地下水中汞含量的真实变化。该结果可供地下流体学科相关工作人员参考。  相似文献   

Aerosol light absorption, black carbon, and elemental carbon at the Fresno Supersite, California   总被引：2，自引：0，他引：2  

Judith C. Chow  John G. Watson  Prakash Doraiswamy  Lung-Wen Antony Chen  David A. Sodeman  Douglas H. Lowenthal  Kihong Park  W. Patrick Arnott  Nehzat Motallebi 《Atmospheric Research》2009,93(4):874-887

Particle light absorption (b_ap), black carbon (BC), and elemental carbon (EC) measurements at the Fresno Supersite during the summer of 2005 were compared to examine the equivalency of current techniques, evaluate filter-based b_ap correction methods, and determine the EC mass absorption efficiency (σ_ap) and the spectral dependence of b_ap. The photoacoustic analyzer (PA) was used as a benchmark for in-situ b_ap. Most b_ap measurement techniques were well correlated (r ≥ 0.95). Unadjusted Aethalometer (AE) and Particle Soot Absorption Photometer (PSAP) b_ap were up to seven times higher than PA b_ap at similar wavelengths because of absorption enhancement by backscattering and multiple scattering. Applying published algorithms to correct for these effects reduced the differences to 24 and 17% for the AE and PSAP, respectively, at 532 nm. The Multi-Angle Absorption Photometer (MAAP), which accounts for backscattering effects, overestimated b_ap relative to the PA by 51%. BC concentrations determined by the AE, MAAP, and Sunset Laboratory semi-continuous carbon analyzer were also highly correlated (r ≥ 0.93) but differed by up to 57%. EC measured with the IMPROVE/STN thermal/optical protocols, and the French two-step thermal protocol agreed to within 29%. Absorption efficiencies determined from PA b_ap and EC measured with different analytical protocols averaged 7.9 ± 1.5, 5.4 ± 1.1, and 2.8 ± 0.6 m²/g at 532, 670, and 1047 nm, respectively. The Angström exponent (α) determined from adjusted AE and PA b_ap ranged from 1.19 to 1.46. The largest values of α occurred during the afternoon hours when the organic fraction of total carbon was highest. Significant biases associated with filter-based measurements of b_ap, BC, and EC are method-specific. Correcting for these biases must take into account differences in aerosol concentration, composition, and sources.  相似文献   

Consequences of Uncertainties in CO<Subscript>2</Subscript> Density for Estimating Net Ecosystem CO<Subscript>2</Subscript> Exchange by Open-path Eddy Covariance     

Penélope Serrano-Ortiz  Andrew S. Kowalski  Francisco Domingo  Borja Ruiz  Lucas Alados-Arboledas 《Boundary-Layer Meteorology》2008,126(2):209-218

Errors in the estimation of CO₂ surface exchange by open-path eddy covariance, introduced during the removal of density terms [Webb et al. Quart J Roy Meteorol Soc 106:85–100, (1980) - WPL], can happen both because of errors in energy fluxes [Liu et al. Boundary-Layer Meteorol 120:65–85, (2006)] but also because of inaccuracies in other terms included in the density corrections, most notably due to measurements of absolute CO₂ density (ρ _c ). Equations are derived to examine the propagation of all errors through the WPL algorithm. For an open-path eddy covariance system operating in the Sierra de Gádor in south-east Spain, examples are presented of the inability of an unattended, open-path infrared gas analyzer (IRGA) to reliably report ρ _c and the need for additional instrumentation to determine calibration corrections. A sensitivity analysis shows that relatively large and systematic errors in net ecosystem exchange (NEE) can result from uncertainties in ρ _c in a semi-arid climate with large sensible heat fluxes (H _s ) and (wet) mineral deposition. When ρ_c is underestimated by 5% due to lens contamination, this implies a 13% overestimation of monthly CO₂ uptake.  相似文献   

印尼苏拉威西岛红土型镍矿的高效快速勘查模式   总被引：3，自引：0，他引：3  

崔敏利 《地质与勘探》2009,45(4):417-422

金属镍是我国紧缺资源之一,印度尼西亚拥有丰富的红土型镍矿,但是由于国外开采,在矿业政策、技术条件、气候条件上面临很多挑战,实施高效、快速、低成本勘探是解决这些问题的根本途径.文章以印尼苏拉威西岛的一个红土型镍矿勘查区为例,应用高精度磁法勘探,通过分析勘查区磁性特征圈定勘探靶区;对实验室和X-荧光仪分析的样品数据进行一元回归分析,将手持X-荧光分析仪成功应用于镍矿体的现场圈定,从而建立了红土型镍矿的高效、快速、低成本的勘查模式.  相似文献   

基于线性放电法的多道脉冲幅度分析器设计     

周能  邓可晴  庄文英 《物探与化探》2022,(1):221-228

多道伽马能谱仪是天然、人工放射性核素测定的必备设备,多道脉冲幅度分析是多道伽马能谱仪的核心,它决定了对核素的分辨能力和分析精度.本文从线性放电法入手,首先介绍了基于线性放电法的多道脉冲幅度分析器的工作原理,给出了分析脉冲幅度和获取能谱道址的方法;其次围绕分析器的8个重要组成部分,详细描述了设计方法,给出了设计依据、设计...  相似文献   

LA-ICPMS原位微区面扫描分析技术及其矿床学应用实例     

周伶俐  曾庆栋  孙国涛  段晓侠  BONNETTIChristophe  RIEGLERThomas  LONGDarrelGF  KAMBERBalz 《岩石学报》2019,35(7):1964-1978

LA-ICPMS原位微区面扫描技术的发展对解析具有包裹体、环带结构的矿物或受多期岩浆/热液活动影响形成的溶蚀再结晶的矿物具有重要的地质意义。黄铁矿作为最普遍的硫化物种类之一,可形成于各种类型矿床中,其微量元素组份记录了矿床形成过程的重要信息。通过LA-ICPMS原位微区面扫描技术获得的黄铁矿晶体内部结构组份信息可用来限定成矿流体的性质、厘定成矿流体的演化规律、示踪成矿物质来源、约束变形变质作用过程中元素的活化和迁移行为,以及约束矿床成因等。本次研究选取了内蒙古二连盆地中巴彦乌拉大型铀矿床、辽宁青城子地区榛子沟铅锌矿、加拿大Pardo砂金矿中的黄铁矿作为研究对象,运用原位微区LA-ICPMS元素面扫描技术揭示其内部组份及结构信息,探索该技术在不同类型矿床中的应用价值。巴彦乌拉大型砂岩型铀矿床中的黄铁矿的内部组构信息显示成矿体系的p H和Eh对硫酸盐还原细菌活动均有影响,并控制与之相关的铀矿化;且成矿体系的p H和Eh受到外界不断供给的地下水的影响,呈振荡性变化。辽宁榛子沟铅锌矿中的黄铁矿的内部组构信息显示矿化过程受到了至少两期流体活动的叠加影响,包括早期同沉积时期的流体以及晚期与燕山期岩浆活动有关的热液流体。加拿大Pardo金矿中黄铁矿的内部组构信息显示矿床中半自形-自形的黄铁矿实际包含碎屑成因的磨圆状核部及后期热液活动形成的增生边;金主要呈浸染状分布在碎屑成因的黄铁矿核部,后期热液活动对金矿化影响微弱。  相似文献