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51.
蔡曙光  李军  李冰 《盐湖研究》2001,9(4):41-47
在大约1mol·dm-3的盐酸水溶液中测定了K2O·MgO·6B2O3·10H2O的溶解焓。结合已获得的其它热化学数据,得出K2O·MgO·6B2O3·10H2O的标准摩尔生成焓为-(12250.35±9.68)kJ·mol-1,并利用“基团贡献法”计算出标准摩尔吉布斯自由能为-11103kJ·mol-1。从而计算出其标准摩尔生成熵和标准摩尔熵。  相似文献   
52.
盐类溶解动力学的数学模型和热力学函数   总被引:5,自引:0,他引:5       下载免费PDF全文
总结了研究盐类溶解动力学的方法和数学模型。采用C语言编写了自动寻优的单线形法,实现了含4个参数的通用程序,并例举了研究实例。另外讨论了热力学函数的处理,也例举了研究实例。  相似文献   
53.
在HCl-NiSO4-H2 O混合溶液中 ,以标准氢电极和银—氯化银电极组成无液接电池 ,恒定溶液总离子强度I和NiSO4在溶液中的离子强度分数yB 的条件下 ,在 2 78 1 5~ 3 2 3 1 5K温度范围内测定下列电池的电动势Pt,H2 ( 1 0 1 3 2 5kPa) |HCl(mA) ,NiSO4(mB) ,H2 O|AgCl-Ag由于体系存在硫酸的二级解离 ,应用数学迭代方法确定平衡体系氢离子的浓度 ,计算了混合溶液中HCl的活度系数γA,结果表明 ,在溶液总离子强度保持恒定时 ,HCl的活度系数服从Harned规则。在溶液组成恒定时 ,盐酸的活度系数logγA 对热力学温度l/T作图 ,是一条直线  相似文献   
54.
本文从目前我国铀矿地质面临的形势和国内外铀矿地质发展的实际情况出发论述了寻找经济可采用可溶浸的铀矿床是我国铀矿地质工作目前的必然选择。铀矿地质工作必须以经济效益为中心,近期的主攻方向是寻找经济可溶浸的铀矿床,尤其是寻找可地浸砂岩型铀矿床。文中还提出了确保铀矿地质找矿目标顺利实际的几项措施。  相似文献   
55.
电解质水溶液的结构   总被引:1,自引:0,他引:1       下载免费PDF全文
房春晖 《盐湖研究》1995,3(2):59-73
本文叙述了盐湖中主要离子Li+、Na+、K+、Mg2+、Ca2+、Cl-、SO_4 ̄2-、NO_3和纯水的结构,介绍了主要研究方法X射线衍射.分析了溶液结构研究历史和现状,对溶液结构研究的未来进行了展望.  相似文献   
56.
房春晖  房艳 《盐湖研究》1995,3(4):66-71
本文介绍了X射线衍射法测定液体结构的一些实验技术,包括光源波长和稳定性、单色X射线的获得、测量条件的选择、实验数据的校正等。  相似文献   
57.
CO2 concentrations at depths of 15,30, and 50 cm were determined over a one-year period in six karst soils in the Malay peninsula. Evidence suggests that the highest single CO2 value (MAXCO2, per cent) recorded at each site/depth provides the best estimate of conditions during groundwater recharge events. Soil depth (cm) and bulk density (BDEN) are the best predictors of MAXCO2, with the equation loglo(MAXCO2) = 1·146 (BDEN) + 0·00698 (DEPTH) - 1·227 accounting for 86 per cent of the variation. This equation is used to model MAXCO2 at seven, more remote sites. Soil throughflow patterns and groundwater recharge points are estimated from slope pantometer and soil depth surveys in order to assess the CO2 concentration with which soil waters ultimately equilibrate before entering the limestone. Limestone weathering seems to be predominantly of the open system type, the overall mean MAXCO2 of 1·65 per cent corresponding with a weathering potential of 167 ppm CaCO3. Weathering potentials vary markedly, ranging from 62–82 ppm on rocky hilltops to more than 280 ppm on certain tower karst footslopes in Selangor and the Kinta Valley and on moderate hillslopes developed in impure limestones in the Boundary Range.  相似文献   
58.
GPS作业过程中的质量控制初探   总被引:1,自引:0,他引:1  
黄勇  王伟  刘卫国  唐枢 《北京测绘》2007,(3):50-53,42
从GPS作业过程的网形设计、外业观测和基线解算等方面简述了在GPS静态定位测量中影响质量的主要因素,并对网形设计、外业观测和基线解算进行了分析,详细分析了影响GPS基线解算结果的主要因素,给出了判别这些因素方法,并对如何消除这些因素的影响提出了相应的处理措施。  相似文献   
59.
In the karst geologic setting of Greenbrier County, West Virginia, USA, the drainage network in the watersheds do not support surface streams, but depend entirely on sinkholes, solution cavities, or injection wells as discharge points for accumulated storm water. By providing a systematic framework for designing and routing storms in this geologic setting, functioning retention and attenuation structures have been developed which are protective of water quality while still safely discharging storm water in a controlled manner to the subsurface. This article provides a rationale for the design methodology and then examines the successful implementation of an attenuation and storm water retention design to manage the surface discharges for an entire watershed. By examining the pre-development flows and evaluating future land use patterns (i.e., installation of impermeable surfaces over large areas), as well as sinkhole conveyance capabilities, it was necessary to examine alternative disposal options for collected storm water as well as devise a basin-wide management strategy to coordinate future development of the watershed. Additionally, innovative water quality measures were implemented to help prevent contamination from preferentially infiltrating into the subsurface as a result of these land development activities.  相似文献   
60.
The conventional impedance inversion method ignores the attenuation effect, transmission loss and inter-layer multiple waves; the smooth-like regularization approach makes the corresponding impedance solution excessively smooth. Both fundamentally limit the resolution of impedance result and lead to the inadequate ability of boundary characterization. Therefore, a post-stack impedance blocky inversion method based on the analytic solution of viscous acoustic equation is proposed. Based on the derived recursive formula of reflections, the 1D viscous acoustic wave equation is solved analytically to obtain zero-offset full-wave field response. Applying chain rule, the analytical expression of the Fréchet derivative is derived for gradient-descent non-linear inversion. Combined with smooth constraints, the blocky constraints can be introduced into the Bayesian inference framework to obtain stable and well-defined inversion results. According to the above theory, we firstly use model data to analyse the influence of incompleteness of forward method on seismic response, and further verify the effectiveness of the proposed method. Then the Q-value sensitivity analysis of seismic trace is carried out to reduce the difficulty of Q-value estimation. Finally, the real data from Lower Congo Basin in West Africa indicate that the proposed approach provide the high-resolution and well-defined impedance result. As a supplement and development of linear impedance inversion method, the non-linear viscous inversion could recover more realistic and reliable impedance profiles.  相似文献   
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