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The program SOL1,written in Turbo-PASCAL for use on a personal computers(IBM-PC orcompatible),has been developed for calculating the equilibrium concentrations of the species inmulticomponent ligand-metal mixtures of up to 21 components and 150 species.The main features arethe easy data input system,the possibility of three different tasks(calculating the composition of a singlesolution,simulating titration curves and calculating the species distribution as a function of pH)andprocedures for drawing the calculated curves on Roland DXY plotters.The program has been tested by astudy of six different complex systems. 相似文献
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LIU Hong-yan ZHU Fa-yan ZHOU Yong-quan WANG Guang-guo FANG Yan ZHANG Wen-qian HAN Li 《盐湖研究》2019,27(2):53-68
The microhydration structure of nickel sulfate aqueous solution has been determined via density functional theory( DFT) calculation and extended X-ray absorption fine structure( EXAFS) spectroscopy. The geometric optimization and energy calculation of nickel sulfate hydrated clusters of the molecular formula [NiSO_4( H_2 O)_n]~0( n = 1-12) were determined via DFT using the B3 LYP method. Several possible initial structures were considered for clusters of each size to locate the equilibrium geometry.Based on the DFT calculation,the favorable structure of Ni~(2+)includes the six-coordinated form of [NiSO_4( H_2 O)_n]~0 clusters. The results of hydration energy calculation suggest that the six-coordinated contact ion pair( CIP) is the stable configuration for small hydration clusters( n≤5),while the solventshared ion pair( SSIP) represents the favorable structure for medium hydration clusters( 6≤n≤10).The solvent is separated by x water molecules( xSIP,x ≥2 is the number of water molecule between Ni~(2+)and SO_4~(2-)) in larger hydration clusters( n≥11). The EXAFS analysis of the NiSO_4 aqueous solutions and NiSO_4·6 H_2 O solid established that Ni~(2+)was surrounded by six water molecules tightly forming an octahedral structure in the first hydration shell,and no CIP was found from 0. 70 mol/L to 2. 22 mol/L( near saturation). The Ni-O distance and coordinated number were 2. 040 ± 0. 020 ? and 6. 0 ± 1. 0,respectively. These results are consistent with the DFT calculations for [NiSO_4( H_2 O)_n]~0 clusters. DFT and EXAFS are powerful techniques that can be used to enhance the resolution of NiSO_4 solution microstructure. 相似文献
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A program for the potentiometric determination of the protonation constants of mononuclear polyproticsubstances is described.A maximum of twelve parameters can be determined simultaneously,includingup to six protonation constants,four electrode calibration parameters,the protolysis constant of thesolvent and the titrant concentration.Optimization is carried out by using the non-simplifiedNewton-Raphson method,which is potentiated by the Marquardt algorithm and a distance speeding-upcoefficient.A direct search method is also used to improve the initial set of values.Variances arecalculated very accurately,since the real Hessian function is used.Statistical weights and ionic strengthcorrections are also considered,The program has been tested by using simulated titration curves ofpolyprotic acids with close constants. 相似文献
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Extraction of Cesium and Rubidium with 4-tert-butyl-2- (α-methylbenzyl) phenol from Salt Lake Brine 
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下载免费PDF全文 PANG Deng-ke FU Zhen-hai ZHANG Zhi-hong ZHANG Yong-ming MA Yan-fang WANG Jing ZHAO Dong-mei 《盐湖研究》2019,27(2):111-119
This work shows the extraction of cesium( Cs~+) and rubidium( Rb~+) from salt lake brine containing potassium( K~+) and magnesium( Mg~(2+)). The results show that 4-tert-butyl-2-( α-methylbenzyl) phenol( t-BAMBP) diluted in sulfonated kerosene( SK) has an excellent extraction effect. Infrared spectroscopic studies indicate that polymerize to form the dimer in the t-BAMBP when Cs~+or Rb~+were extracted. The effects of K~+,Mg~(2+),t-BAMBP concentration,the volume ratio of organic phase to aqueous phase( O/A) and the alkalinity( pH) of aqueous phase were investigated.The K~+and Mg~(2+)should be eliminated through precipitating before the extraction and separation of Cs~+and Rb~+. The optimum extraction conditions of the experimental brine were as follows: 0. 8 mol/L t-BAMBP diluted in SK,pH≥13,a phase ratio of 1: 1,and an extraction contact time of 2 min at room temperature. The optimal extraction yields of Cs~+and Rb~+were as high as 100% and 85. 8%,in addition,8. 76% of K~+was co-extracted. Further work would increase the extraction yield and selectivity of Rb~+and realize the efficient separation of Cs~+and Rb~+from brine. 相似文献
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The dynamic headspace titration of the volatile constituents of the black truffle(Tuber Melanosporum)isplanned to be carried out with the new gas chromatographic device DCI using Tenax trapping.In thispaper the necessary optimization of the experimental factors which influence the desorption of thevolatiles from the sample and the adsorption on the trap is carried out by experimental design.The studyof the isoresponse curves makes it possible to determine the optimum conditions for a rapid titration ofhighest sensitivity and reproducibility,avoiding water trapping. 相似文献
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新疆巩乃斯河水化学分析 总被引：4，自引：1，他引：3
通过对伊犁河支流巩乃斯河河水取样分析,结果表明:巩乃斯河河水阴离子中HCO3-占优势,阳离子中Ca2+占主要地位。主要离子含量表现为阴离子HCO3-C l-SO42-;阳离子Ca2+Na++K+Mg2+。巩乃斯河河水均属于HCO3-C l-Ca-Na型水。河水pH为7.56~8.01;矿化度为80~155 mg/L;总硬度为0.620~1.446 mmol/L;河水总碱度为0.778~1.676 mmol/L。另外,对离子浓度的空间变化及离子的来源分析研究表明,巩乃斯河流域的地形,地貌及气候的差异决定了河水主要离子浓度、pH和矿化度自河流上游至下游,基本呈现先逐步降低后显著升高的趋势;巩乃斯河河水主要离子来源于河水对基岩的溶滤作用,同时钠长石斑岩及人类活动所产生的物质也是主要离子的来源之一。 相似文献
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Application of principal component analysis to Cu(II)-ethanolamine complex formation data is shown.Determination of the number of complex species is obtained from the rank of the matrix of spectral datausing either Gauss elimination or factorial analysis.Relevant information concerning species distributionversus pH is obtained from the plot of the signficant factors upsurging from the evolution of spectraltitration data. 相似文献
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湖北江汉盆地潜江凹陷深层地下卤水水文地球化学研究 总被引：2，自引：2，他引：2
潜江凹陷是我国东部的一较大型油盐沉积盆地．凹陷内的Ｑ组（渐新统）含盐系地层是一套内陆盐湖相沉积，其中不仅蕴藏着丰富的石油和固体盐类，而且卤水资源也十分丰富．卤水为高矿化度、高ＳＯ含量、低Ｃａ（２＋）、Ｍｇ（２＋）含量的硫酸盐型陆相古盐湖沉积卤水．卤水的ｐＨ值平均为５．６６，总矿化度平均为２８３．２５克／升．水盐体系主要为Ｎａ，Ｋ／／Ｃｌ，ＳＯ４－Ｈ２Ｏ，古卤水水化学类型为Ｎａ２ＳＯ４亚型．卤水中含近２８种化学成分，ＳＯ的平均含量达９６６５．８毫克／升，Ｃａ（２＋）和Ｍｇ（２＋）的平均含量才分别为８９９．４毫克／升和１７３．８毫克／升．Ｋ、Ｂ、Ｌｉ、Ｂｒ、Ｉ等的含量较大，Ｋ、Ｂ、Ｌｉ的含量随Ｃｌ浓度的增加而增加，Ｂｒ、Ｉ的含量随矿化度的增加而增加，随ＳＯ浓度的增加而减少．卤水中绝大多数离子的含量在沉积盆地浓缩中心区大，在理深较大的第四、五、六水层高． 相似文献
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A computer program for reconstructing environmental variables (e.g. lake-water pH) from fossil assemblages (e.g. diatoms) by weighted averaging regression and calibration is described. The estimation of sample-specific errors of prediction by bootstrapping is outlined. The program runs on IBM-compatible personal computers. 相似文献
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A curve-fit model of the relationship between soil pH (A horizon) and climate forms the basis of a map of predicted pH for the conterminous United States. This map was produced with the aid of a large climatic data base, a computer mapping program and subroutines to map modeled values of soil pH. Patterns of pH follow well-recognized patterns of climate, although the pH of 7 line deviates greatly from Marbut's line dividing pedalfers from pedocals. The overall accuracy of the map and model was checked using a validation data set. Geographic patterns of pH are realistic, although land use, topography, and parent material may cause local variations about the predicted mean for a given region. Several apparently anamolous map patterns were also checked but found to be accurate. Prediction of the detailed pattern of pH will require variables in addition to climate. 相似文献
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Electromagnetic induction by a non-uniform source over a layered half-space is studied. A method is described for solving such problems when the current intensity distribution is such that no analytic integration to obtain the field quantities is possible. A number of models are considered using a general computer program. Apparent resistivity curves are calculated and compared with previous results. Phase curves and field component profiles are calculated. 相似文献
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库仑法和电化学阻抗法是测量锂离子扩散系数有效的测量手段。以实验室自制的LiFePO4为实验电池正极材料,介绍如何用库仑法和阻抗法测试并计算电极材料的锂离子扩散系数。库仑法计算得到锂离子扩散系数由Li1-xFePO4(x=0)的9.6×10-9cm2.s-1变化为Li1-xFePO4(x=0.7)的1.1×10-11cm2.s-1。用阻抗法的两种模型,分别计算了Li1-xFePO4(x=0.65)的电池材料的锂离子扩散系数,结果分别是8.5×10-11cm2.s-1和3.1×10-12cm2.s-1。三种方法的计算结果接近。 相似文献
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以新疆奇台地区碱化土壤为研究对象,通过分析碱化土壤实测光谱反射率曲线与八大离子、pH、碱化指标相互间的相关关系,建立基于离子光谱特征波段反射率的各碱化指标一元及多元光谱反演模型,并对其精度进行验证。结果显示:Na^+、CO_32-、HCO_3^-含量与光谱反射率正相关,最高点的相关系数分别为0.710、0.798、0.749,而Ca2+、Mg2+含量与光谱反射率负相关,相关系数最高均不超过-0.370,反映出前3类离子含量与光谱反射率关系更为密切。SAR(钠吸附比)和ESP(碱化度)与Na+相关系数同为0.954,TA(总碱度)、RSC(残余碳酸钠)、pH与CO_32-的相关系数分别为0.946、0.949和0.953,总体上Na^+和CO_32-含量对各碱化指标的影响更大。各碱化指标与土壤光谱反射率的相关性TA>RSC>ESP>pH>SAR;其中TA与光谱反射率的相关系数达到0.863。碱化指标TA的离子光谱特征波段反射率反演模型精度最好,其R^2为0.703,比利用实测光谱反射率建立的pH反演模型的R^2高约14%,说明前者精度更高,能更好地反映研究区内土壤的碱化程度。利用离子光谱特征波段反射率实现对土壤碱化的预测会成为今后研究的重点。 相似文献
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应用循环曲线法研究了在353 K的乙酰胺-尿素-NaBr熔体中Co2+在Cu电极上的电化学行为,获知Co2+电还原为金属Co是一步不可逆过程,测得a=0.25和Do=3.24×10-6cm2.s-1;而Ce(Ⅲ)、Sm(Ⅲ)不能单独还原为Ce和Sm,但可以被Co(Ⅱ)诱导而共沉积;由恒电位电解法得到非晶态的Ce-Sm-Co合金膜,合金膜中Ce和Sm的含量随电位、时间和浓度的变化而变化。其合金膜中Sm的最高质量分数可以达到47.98%,Ce的最高质量分数可以达到47.32%。 相似文献
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腾格里沙漠西南缘地下水水化学形成特征及演化 总被引：6，自引：2，他引：4
以邓马营湖区为核心,对腾格里沙漠西南缘地下水数据进行水文地球化学特征分析,并运用PHREEQC2.0软件反向模拟沿运移路径地下水的补给机理及演化过程。结果显示:受水文地质条件制约,从山前洪积扇地下水的补给区深入腾格里沙漠过渡带再到邓马营湖区中深层地下水,水化学类型从HCO3-—Ca2+—Mg2+型过渡为Cl-—SO24-—Na+—Mg2+型再过渡到HCO3-—SO42-—Na+型。其影响因素基本包括:溶滤与蒸发浓缩作用、阳离子交换吸附作用、以及微弱的混合作用和地下水补给水源水化学成分控制。矿物饱和指数以及反向水文化学地球化学模拟的结果显示,由西南向东北沿水流方向各物质溶解沉淀情况复杂,除斜长石与方解石外,岩盐、石膏、白云石等浓缩沉淀显著,表明蒸发浓缩作用控制强烈。 相似文献