改进原子吸收分光光度计的输出显示   总被引：1，自引：0，他引：1  

王永青  孙荣霞  周颖昌  郝雷  孙雪  郭晓军 《岩矿测试》2004,23(1):79-80

采用7107A/D转换器,将原子吸收分光光度计指针式显示改为数字化显示,给出了改进方法,介绍了7107A/D转换器及显示电路原理.通过改进提高了仪器输出读数的分辨率和灵敏度.  相似文献   

悬浮进样石墨炉原子吸收法测定纳米氧化锆粉体中的微量铝   总被引：2，自引：0，他引：2  

彭勇朱明燕  侯书恩汪丽霞 潘勇 《岩矿测试》2004,23(2):109-112

采用水介质直接分散纳米氧化锆粉体悬浮进样，以水标准溶液绘制校正曲线，石墨炉原子吸收法测定其中的微量Al。系统研究了Al的原子化和灰化行为，不同分散介质及基体元素对测定Al的影响，获得了测定Al的优化条件。方法对Al的检测限为0．5ng／g，Al的线性范围为0～2．5mg／L，基体ZrO2的质量浓度小于2g／L时，对Al的测定无干扰，悬浮进样直接测定的RSD(n=5)为6．0％。样品的测定结果与其他方法对比基本一致。  相似文献   

活性炭对无机汞和苯基汞的吸附行为探讨   总被引：3，自引：0，他引：3  

侯明钱建平  胡存杰 《岩矿测试》2004,23(4):263-267

试验了活性炭对无机汞和苯基汞的吸附和解吸行为。结果表明，在活性炭用量为0．2g，ψ=0．5％的王水介质中搅拌1．5h，无机汞和苯基汞的吸附率均达96％以上，无机汞和苯基汞的吸附容量分别为82．5μg/g和66．0μg/g。吸附后的无机汞和苯基汞分别用含有60mg EDTA的2．8mol/L HNO3溶液和5．6mol/L HNO3-1．0mol/L H2SO4溶液定量洗脱，用冷原子吸收光谱法测定，实现了无机汞和苯基汞的定量分离。对2μg/L的无机汞和苯基汞进行测定，相对标准偏差(n=11)分别为5．4％和6．2％。在实际水样中加标回收和测定，无机汞和苯基汞的回收率分别为97．8％～108％、94．0％～106％。  相似文献   

Infrared spectral reflectance characterization of the hydrothermal alteration at the Tuwu Cu–Au deposit, Xinjiang, China     

K. Yang  C. Lian  J. F. Huntington  Q. Peng  Q. Wang 《Mineralium Deposita》2005,40(3):324-336

Short-wave infrared (SWIR) reflectance spectroscopy was used to characterize hydrothermal minerals and map alteration zones in the Tuwu Cu–Au deposit, Xinjiang, China. The Palaeozoic hydrothermal system at Tuwu is structurally controlled, developed in andesitic volcanic rocks and minor porphyries. Hydrothermal alteration is characterized by horizontally zoned development of quartz, sericite, chlorite, epidote, montmorillonite and kaolin about individual porphyry dykes and breccia zones, as is shown by changes outward from a core of quartz veining and silicification, through an inner zone of sericite + chlorite to a marginal zone of chlorite + epidote. The alteration system comprises several such zoning patterns. Silicification and sericitization are spatially associated with Cu–Au mineralization. Zoning is also shown by compositional variations such that Fe-rich chlorite and Al-rich sericite occur preferentially toward the core and the most intensely altered parts, whereas Mg-rich chlorite and relatively Al-poor sericite are present on the margin and the relatively weakly altered parts of the hydrothermal alteration system. The compositions of chlorite and sericite, therefore, can be potentially used as vectors to Cu–Au mineralization. Montmorillonite and kaolinite, of probable weathering origin, are located near the surface, forming an argillic blanket overlying Cu–Au mineralization. Sporadic montmorillonite is also present at depth in the hydrothermal alteration system, formed by descending groundwater. Presence of a well-developed kaolinite-bearing zone on the surface is an indication of possible underlying Cu–Au mineralization in this region. Epidote occurs widely in regional volcanic rocks, as well as in variably altered rocks on the margin of the hydrothermal mineralization system at Tuwu. The widespread occurrence of epidote in volcanic country rocks probably reflects a regional hydrothermal alteration event prior to the localized, porphyry intrusion-related hydrothermal process that led to the Cu–Au mineralization at Tuwu.  相似文献   

The Newmark scheme as velocity–stress time-staggering: an efficient PML implementation for spectral element simulations of elastodynamics     

Gaetano Festa  Jean-Pierre Vilotte 《Geophysical Journal International》2005,161(3):789-812

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复合地基垫层的减振作用分析     

王凤池  朱浮声  林勇 《世界地震工程》2004,20(3):109-113

从垫层桩基的减振机理出发，分析了垫层桩基和复合地基的等效性，提出了复合地基的减振机理和减振动力模型。复合地基的减振性能主要体现在减小振幅、粘滞阻尼耗能和摩擦耗能上。根据复合地基的减振机理，可把基础和垫层简化为多自由度的质、阻、弹振动体系，同时考虑滑动摩擦作用。最后，提出了按减振思想设计和施工复合地基的要求。  相似文献   

锶在砂岩和花岗岩中的分配系数及吸附机制研究   总被引：6，自引：0，他引：6  

王青海  李晓红  顾义磊  陈金华 《矿物岩石》2004,24(2):30-34

采用批示法(BATCH)研究不同浓度条件下^87Sr在某放射性废物预选处置场围岩—花岗岩和砂岩中的吸附比，并利用面积修正公式求取分配系数。花岗岩和砂岩对^87Sr的吸附机制研究结果表明：花岗岩和砂岩对^87Sr的吸附机制为岩石中的Ca和K与水中的Sr之间的离子交换。由于砂岩中长石含量大，且胶结物质为钙质和泥质，因此砂岩对。^87Sr的吸附能力比花岗岩强。  相似文献   

大气对NOAA通道辐射透过率的影响研究   总被引：2，自引：2，他引：2       下载免费PDF全文

王伟民  周祖刚  李海民 《气象科学》2004,24(3):285-293

本文利用LOWTRAN7大气辐射计算模式，对NOAA三个通道分别选取不同的模式大气进行计算，得到了各种模式大气的大气透过率。详细计算了探测路径上卷云、不同气溶胶模式、大气温度、水汽含量变化等气象要素及大气成分的变化对大气透过率的影响，得出一些有意义的结论。  相似文献   

DOAS Zenith Sky Observations: 1. BrO Measurements over Bremen (53°N) 1993–1994     

M. EISINGER  A. RICHTER  A. LADSTÄTTER-WEIßENMAYER  J. P. BURROWS 《Journal of Atmospheric Chemistry》1997,26(1):93-108

Observations of stratospheric BrO over Bremen (53°N) are reported for winter and early spring periods of 1993 and 1993/94. The BrO was observed by ground-based near-UV absorption spectroscopy of sunlight scattered in the zenith. Differential slant column densities for solar zenith angles 90°/80° in the range of9× 10¹³ (detection limit) to 4.5×10¹⁴ molecules/cm² having a high day-to-day variability were found. For the majority of the measurements no significant difference was observed between the morning and evening behaviour of BrO. Exceptions are the morning measurements from the winter of 1992/93 where an accelerated production of BrO was observed. We believe the latter best to be explained by the early morning rapid photolysis of elevated amounts of photo-labile Br-reservoirs formed during the night. The largest differential slant column densities of BrO were measured in December 1993 when the temperatures at 30 hPa dropped below 205 K. This might be an indication of heterogeneous conversion of bromine compounds on sulfate and other aerosols.  相似文献   

关于云和云天大气对太阳辐射的吸收异常   总被引：8，自引：4，他引：8       下载免费PDF全文

陈洪滨 《大气科学》1997,21(6):750-757

本文是关于云和云天大气对太阳辐射吸收异常问题的一个综述，总结了到目前为止的对水云异常吸收的一些解释，指出这些解释的合理性和缺陷。本文的重点在于介绍近年来论争激烈的有云大气的异常吸收问题，对存在和不存在增强吸收的两种截然相反的观点都做了较详细的评述。  相似文献