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三峡井网是我国第 1个以监测水库诱发地震的地下水前兆为目的的专业网 ,由 8口观测井构成。其中 4口井台有水温和土氡观测 ,3口井台有降雨、气压与气温观测 ,另有一处库水位观测 ;每口井台中均有水位动态观测。观测项目共有 2 6项。文中主要介绍三峡井网的观测技术系统 ,其中包括井网的技术系统与井台的技术构成 ,各类仪器设备的技术指标与安装调试 ,相关的供电、通讯与防雷等技术支撑设施。此外 ,还简要介绍了观测技术系统的运行及其基本结果 相似文献
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M. V. Goryunov G. Varga Z. Dankházi A. V. Chukin I. Felner E. Kuzmann V. I. Grokhovsky Z. Homonnay M. I. Oshtrakh 《Meteoritics & planetary science》2023,58(10):1552-1562
A fragment of Mundrabilla IAB-ung iron meteorite was analyzed using optical microscopy, scanning electron microscopy (SEM) with energy dispersive spectroscopy (EDS), X-ray diffraction (XRD), magnetization measurements, and Mössbauer spectroscopy. The polished section of meteorite fragment characterization by optical microscopy and SEM shows the presence of the γ-Fe(Ni, Co) phase lamellae, plessite structures and schreibersite inclusions in the α-Fe(Ni, Co) phase. EDS indicates variations in the Ni concentrations in the following ranges: (i) ∼6.3–6.5 atom% in the α-Fe(Ni, Co) phase and (ii) ∼22 to ∼45 atom% in the γ-Fe(Ni, Co) phase lamellae including the range of ∼29–33 atom% of Ni leading to the paramagnetic state of the γ-Fe(Ni, Co) phase. Schreibersite inclusions contain ∼23 atom% of P, ∼33 atom% of Fe, ∼43 atom% of Ni, and ∼0.7 atom% of Co. Plessite structure contains the average Ni concentration of ∼17 atom% while detailed EDS analysis shows: (i) the lowest Ni concentrations of ∼5 to ∼8 atom%, (ii) the intermediate Ni concentrations of ∼9 to ∼19 atom%, and (iii) the highest Ni concentration up ∼38 atom% (some individual micro-grains demonstrate up to ∼47 and ∼59 atom% of Ni) that may indicate the presence of the (i) α-Fe(Ni, Co), (ii) α2-Fe(Ni, Co), and (iii) γ-Fe(Ni, Co) phases. These may be a result of the γ-phase decomposition with mechanism γ → α + α2 + γ that indicates a slow cooling rate for Mundrabilla IAB-ung iron meteorite. The presence of ∼98.6 wt% of the α-Fe(Ni, Co) phase and ∼1.4 wt% of the γ-Fe(Ni, Co) phase is found by XRD while schreibersite is not detected. Magnetization measurements show the saturation magnetization moment of Mundrabilla IAB-ung of 188(2) emu g−1 indicating a low average Ni concentration in Fe-Ni-Co alloy. Mössbauer spectrum of the bulk Mundrabilla powder demonstrates five magnetic sextets related to the ferromagnetic α2-Fe(Ni, Co), α-Fe(Ni, Co), and γ-Fe(Ni, Co) phases and one singlet associated with the paramagnetic γ-Fe(Ni, Co) phase, however, there are no spectral components corresponding to schreibersite. Basing on relatively larger and smaller values of the magnetic hyperfine field, two magnetic sextets associated with γ-Fe(Ni, Co) phase can be related to the disordered and more ordered γ-phases. The iron fractions in the detected phases can be roughly estimated as follows: (i) ∼17.6% in the α2-Fe(Ni, Co) phase, (ii) ∼68.5% in the α-Fe(Ni, Co) phase, (iii) ∼11.5% in the disordered γ-Fe(Ni, Co) phase, (iv) ∼2.0% in the more ordered γ-Fe(Ni, Co) phase, and (v) ∼0.4% in the paramagnetic γ-Fe(Ni, Co) phase. 相似文献
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地质样品痕量氯溴和硫的X射线荧光光谱法测定 总被引:16,自引:8,他引:16
报道了粉末压样-X射线荧光光谱法测定地质样品中痕量Cl、Br、S的分析方法。采用水系沉积物、岩石和土壤等国家一级标准物质进行校准。实验表明,对于不同岩性样品中Br的分析,特别是当Br的含量低于2μg/g时,采用谱峰强度(未扣除背景)与背景强度的比进行校准所得到的结果,明显优于铑靶线的Compton散射线内标法,分析精度(RSD,n=6)为2.4%-15.3%,大多数优于10%;平均值的相对误差低于24%。对于Cl的分析,只需对Ca的影响加以校正即可得到非常好的结果;不同样品中Cl的分析精度(RSD,n=6)为2.1%-13.6%,大多数优于5%;平均值的相对误差不大于25%,多数优于10%。S的校准曲线的离散性较大,矿物学效应是影响S分析准确度的主要因素,其分析精度(RSD,n=6)为0.87%-5.6%,除个别样品外,平均值的相对误差优于36%。Cl和S均存在分析结果随测量时间(次数)的增加而增高的现象,必须在制样后立即测量。方法的检出限(μg/g)Br、Cl、S分别为0.43、5.8和2.2。 相似文献