原子荧光光谱仪工作温度对水体中砷含量测定的影响   总被引：1，自引：1，他引：0  

刘景龙  吴巧丽 《岩矿测试》2019,38(2):228-232

氢化物发生-原子荧光光谱法受到仪器工作温度的影响主要来自于氢化物发生反应和仪器漂移,工作温度升高会增加仪器的背景值,而过低的工作温度又不利于氢化物发生反应进行。本文根据原子荧光光谱测定水体中砷的方法,在10℃、20℃和30℃的工作温度条件下,分别测试校准曲线、空白样品、自配质控样品和有证标准物质来确定最适宜的工作温度。结果表明:三个温度条件下的校准曲线均具有较好的线性相关性;仪器工作温度过高会引起空白荧光值变大、检出限升高,同时会造成仪器灵敏度的降低,增加了样品测试误差,测试结果不能满足准确度的要求。本文提出,利用原子荧光光谱法测定砷含量时,应控制仪器工作温度在10～20℃,并且保证温度变化相对稳定。  相似文献   

基于原位多元素成像分析龙马溪组笔石成因及地质意义     

竺成林  王华建  叶云涛  王晓梅  黄家旋  朱玉梅  杨瑞东 《岩矿测试》2019,38(3):245-259

上扬子地区龙马溪组黑色页岩富含笔石,多以碳质薄膜形式富集于富有机质层段。前期研究多关注笔石形态和成岩后的演化过程,对笔石埋藏和早成岩阶段所经历地球化学作用的研究较少,笔石成因仍缺乏直接证据。本文利用激光剥蚀电感耦合等离子体质谱(LA-ICP-MS)技术对宁203井龙马溪组笔石进行原位微区多元素扫描成像,对主量成矿元素分布与富集程度进行解析,发现了碳质薄膜笔石体表面富集Mg、Al、Si、Fe元素,富集倍数在1.5～10倍以上,Sr/Ba值(1.4～2.3)则明显低于围岩(5.0),指示黏土矿物包埋是笔石碳化的主要途径,包埋形成的硫化微环境导致部分笔石发生黄铁矿化。结合面笔石率、有机质、黄铁矿、黏土矿物含量和δ~(13)C_(org)值的剖面垂向变化及相关性分析,提出早期微生物席繁盛和后期硫酸盐还原菌繁盛导致水岩界面孔隙水普遍缺氧,是笔石和有机质大量埋存的主要原因。本研究结果不仅揭示了龙马溪组笔石的埋藏矿化机制,也为有机质富集和黑色页岩形成的控制因素研究提供了新思路。  相似文献   

甲烷动态反应电感耦合等离子体质谱法测定地下水中痕量硒   总被引：2，自引：2，他引：0  

刘金巍  刘雪松  边超  张涛  张智印  魏建朋 《岩矿测试》2019,38(1):85-91

地下水中的硒含量一般低于1μg/L,大量氯离子等形成的多原子离子干扰和较低的电离程度,严重影响常规模式ICP-MS测定地下水中痕量硒的准确性,且检出限难以满足实际需要。本文建立了应用动态反应池电感耦合等离子体质谱(DRC-ICP-MS)技术测定地下水中痕量硒的方法,采用乙醇为增感剂,甲烷为反应气,通过实验优化了甲烷流量、乙醇含量、雾化气流速、低质量截取(RPq)、射频发生器(Rf)功率、离子驻留时间等条件对硒不同质量数测定的影响。结果表明:乙醇、甲烷可显著降低Ar等形成的多原子离子干扰,乙醇可明显提高硒的响应强度;在优化实验条件下,除74Se外,各离子的校准曲线线性关系良好(R≥0. 9996),方法检出限为0. 02～0. 03μg/L,低浓度和高浓度样品测试结果的RSD 2%(n=5),平均加标回收率为95. 7%。本方法样品前处理简单,使用设备单一,可满足大批量地下水中痕量硒的测定要求。  相似文献   

地质样品中高精度铬同位素分析纯化技术研究进展   总被引：1，自引：1，他引：0  

史凯  朱建明  吴广亮  王静  曾理 《岩矿测试》2019,38(3):341-353

随着多接收器热电离质谱仪(MC-TIMS)和多接收器电感耦合等离子体质谱仪(MC-ICP-MS)的发展,高精度铬(Cr)同位素测试已成为可能。铬同位素在地球、环境、农业生态和宇宙化学等科学领域中已显示出良好的应用潜力。然而,样品的纯化分离、干扰和仪器质量分馏的校正,依然是制约铬同位素高精度测试的重要因素。本文在近年来铬同位素分析技术最新进展的基础上,结合本课题组已有的研究,对陨石、地质和环境等各类样品中铬同位素的分离纯化方法、MC-ICP-MS测试中干扰与质量歧视校正等进行了详细综述。本文认为,阴阳离子树脂交换联用与过硫酸钾等强氧化剂的结合,可以进行低铬高基质样品的有效纯化,是一种较为普适性的纯化方法。使用铬同位素双稀释剂校正质量歧视效应,在MC-ICP-MS的中高分辨与静态测量模式下,不仅可以有效分开多原子离子的干扰,而且也可以进行高精度铬同位素分析,其δ~(53/52)Cr的分析精度与TIMS相当,可以达到0.04‰(2SD),且最低测试浓度可低至10ng,能够实现超微量铬的同位素分析。  相似文献   

Technical Challenges and Engineering Solutions for Gas Pipelines in Permafrost Regions: A Review     

Xinze Li  Huijun Jin 《地球科学进展》2019,34(11):1131-1140

Oil and gas pipelines in permafrost regions differ greatly from those in temperate climate zones. People only know that these pipelines were constructed in remote areas with fragile environments. However, gas pipeline engineering, construction, operation and management will face a series of unique problems because of unforgiving environment, special hydrogeology, engineering geology, and freezing and thawing disasters. Being different from the Trans-Alaska Pipeline System, Roman Wells Oil Pipeline, China-Russia Crude Oil Pipeline from Mo’he to Daqing and Golmud-Lhasa Oil Products Pipeline, natural gas pipelines in permafrost regions face new problems and challenges in many areas including different transporting media, gas flow temperature control and environmental protection. This paper systematically reviewed issues such as chilled transporting processes, coupled hydrothermal-hydraulic-mechanical modeling of the pipe-soil system, temperature overrun in station outage scenarios, engineering constraints of stress-based design, single laying method and low reliability of monitoring system during operating stage. Initial framework solutions were proposed in the hope of identifying new approaches for gas pipeline in northern and upland permafrost regions.  相似文献   

Simultaneous measurements of the two-dimensional distribution of infrared laser intensity and temperature in a single-sided laser-heated diamond anvil cell     

Kamil M. Bulatov  Pavel V. Zinin  Yulia V. Mantrova  Aleksey A. Bykov  Maksim I. Gaponov  Alexsandr S. Machikhin  Ivan A. Troyan  Igor B. Kutuza 《Comptes Rendus Geoscience》2019,351(2-3):286-294

In this report, we demonstrate that combining the laser heating system in a diamond anvil cell (LH-DAC) with a tandem acoustic-optical tunable filter (LH-DAC–TAOTF) allows for the simultaneous measurement of (a) the relative infrared (IR, 1070 nm) power distribution on a specimen surface in the DAC; (b) the temperature distribution under laser heating of a specimen under high-pressure in a DAC; it also (c) provides an opportunity to control the shape of the IR laser spot on the surface of the heated specimen. The effect of the π-shaper on the shape and the position of the focus of the IR laser beam on a specimen using a TAOTF is also presented. For a 10× long-working distance objective, the smallest diameter of the IR laser was found to be around 10 μm, when the focal plane coincides with that of the imaging optical system of LH-DAC. The highest diameter of the IR laser was shown to be 20 μm when the rim of the π-shaper was set at 3 μm. It is demonstrated also that the TAOFT not only permits to measure the two-dimensional (2-D) distribution of the IR laser power, but also allows for the alignment of the laser before each heating event at different pressures.  相似文献   

激光三维扫描技术用于古建筑测绘的研究   总被引：19，自引：5，他引：14  

余明  丁辰  过静珺 《测绘科学》2004,29(5):69-70

传统的古建筑测绘以直尺和角尺、垂球等工具直接量取建筑物及其构件的尺寸,而获取的最终资料是"图样"(即图纸)和一些文字记录。而重要古建筑在大规模修复前则要求进行精确的测绘工作,为古建筑保护提供第一手资料,同时也为研究中国古建筑史和建筑理论提供重要资料。激光三维扫描技术能够快速、精确、多方位地获取静态物体的三维模型,并对模型进行进一步的分析和数据处理。该方法在故宫的修复测绘中进行了大量的实验,取得了较好的效果,为古建筑测绘的数字化提供良好的平台。  相似文献   

基于SLR时间序列构建STRF及其与ITRF2008转换关系的研究     

何丽娜  王解先  宋淑丽  朱文耀  王成 《大地测量与地球动力学》2011,31(6):104-108

利用SLR时间序列与ITRF2008的公共参考站的坐标及速度信息,实现两者间的欧几里得标准相似变换,以核心参考站在1983—2008年的SLR时间序列解算了各历元与ITRF2008的转换参数,并对转换参数进行统计分析,结果可靠。  相似文献   

荒漠植物花棒耐盐性的傅立叶红外光谱法研究   总被引：6，自引：5，他引：1  

王淑莉  赵昕  谭会娟  刘玉冰 《中国沙漠》2008,28(5):874-878

试验以荒漠植物花棒幼苗为材料,应用傅立叶红外光谱（FTIR）法研究了NaCl胁迫下花棒叶片主要有机化合物含量和蛋白质结构的变化以及叶片K+和Na+含量。结果表明,叶片Na+、K+含量随着0~255 mM NaCl盐胁迫逐渐增强而变化,导致Na+/K+比值逐渐降低,显示出盐胁迫下花棒幼苗具有”吸钾排纳”特性。花棒幼苗再170 mM NaCl的高浓度胁迫下24 h,叶片中蛋白质、酯类和碳水化合物含量大幅度增加。花棒的蛋白质二级结构中1 665/1 638 cm-1比值的逐渐降低。揭示出花棒植株通过增强蛋白质、酯类和碳水化合物合成代谢调控能力抵御盐胁迫的损伤,而且花棒蛋白质二级结构更趋稳定,与叶片中Na+/K+比值的变化趋势显著相关。因此花棒为了适应高浓度盐胁迫,具有叶片蛋白质、酯类快速合成以及蛋白质构象更趋于稳定的积极响应。  相似文献   

Interaction of waves,currents and tides,and wave-energy impact on the beach area of Sylt Island   总被引：3，自引：1，他引：2  

Andrey Pleskachevsky  Dieter P. Eppel  Hartmut Kapitza 《Ocean Dynamics》2009,59(3):451-461

Erosion due to waves is an important and actual problem for most coastal areas of the North Sea. The objective of this study was to estimate the impact of wave action on the coastline of Sylt Island. From a 2-year time series (November 1999 to October 2001) of hydrological and wave parameters generated with a coupled wave–current modelling system, a period comprising storm ‘Anatol’ (3–4 December 1999) is used to investigate the effects of waves on currents and water levels and the input of wave energy into the coastline. The wave-induced stress causes an increase of the current velocity of 1 m/s over sand and an additional drift along the coast of about 20 cm/s. This produces a water level increase of more than 20 cm in parts of the tidal basin. The model system also calculates the wave energy input into the coastline. Scenario runs for December 1999 with a water level increase of 50 cm and wind velocity increased by 10% show that the input of the wave energy into the west coast of Sylt Island increases by 30% compared to present conditions. With regard to the forecasted near-future (Woth et al., Ocean Dyn 56:3–15, 2006) increase of strong storm surges, the scenario results indicate an increased risk of coastal erosion in the surf zone of Sylt Island.  相似文献