沉积CaCO3与金属离子界面反应动力学研究

金属离子与沉积碳酸盐之间２同反应动力学模拟实验表明,由于ＣａＣＯ３快速溶解和溶液ＰＨ急剧上升,大部分Ｐｂ＾２＋、Ｚｎ＾２＋离子与溶液中ＣＯ３＾２－和ＯＨ＾－离子反应生成白铅矿ＰｂＣＯ３、水白铅矿Ｐｂ３（ＯＨ）２（ＣＯ３）２,或Ｚｎ（ＯＨ）３和锌矿Ｚｎ（ＯＨ）６（ＣＯ３）２沉淀于体相溶液中,仅有少部分Ｐｂ＾２＋、Ｚｎ＾２＋通过扩散与ＣａＣＯ３表面发生离子交换反应。２５℃时,Ｐｂ＾２＋溶液中以白铅矿沉     

麦饭石在腐殖酸及重金属离子的吸附作用

研究了麦饭石对腐殖酸和重金属离子（Ｈｇ＾２＋,Ｐｂ＾２＋,Ｃｕ＾２＋,Ｚｎ＾２＋,Ｃｄ＾２＋）的吸附作用,实验结果表明麦饭石对腐殖酸和重金属离子都具有较好的吸附性能,且腐殖酸的存在有利于麦饭石对重金属离子的吸附,ｐＨ值是影响吸附的重要因素,当ｐＨ值５．０～６．０时,麦饭石同时吸附腐殖酸和重金属离子的效果最好,麦饭石在吸附腐殖酸和重金属离子的同时能溶出微量元素硒,这对于大骨节病的防治有得要意义。     

硫化物吸附金属离子的实验研究：——Ⅱ类型

合成ＰｂＳ、ＺｎＳ对金属离子Ａｇ＾＋、Ｃｕ＾２＋、Ｃｄ＾２＋、Ｚｎ＾２＋、Ｆｅ＾２＋、Ｍｎ＾２＋、Ｍｇ＾２＋、Ｓｂ＾２＋和Ｂｉ＾３＋的吸附等温线（５０℃）研究表明，其可分为Ａ、Ｂ、Ｃ三类：Ａ类，线性型，即吸附量随吸附离子浓度增加而呈线性上升，并表现出百分之百吸附，属于此类的吸附有ＰｂＳ对Ａｇ＾＋、Ｃｕ＾２＋离子吸附和ＺｎＳ对Ａｇ＾＋、Ｃｕ＾２＋、Ｃｄ＾２＋离子的吸附；Ｂ类，朗谬尔型，即随吸附离子的     

锌的四元络物光度法研究及应用

研究了Ｚｎ＾２＋－２－（３,５－二溴－２－吡啶偶氮）－５二乙氨基苯酚－酒石酸钾钠－吐温８０体系形成四元混配合物显色反应条件,确定了络合物的组成,络合物的最大吸收波长λｍａｘ＝５７２ｎｍ方法用于测定脱脂奶粉,人发样品中的微量Ｚｎ＾２＋,结果满意。     

2—[2—（5—甲基苯并噻唑）偶氮]—5—二乙氨基苯甲酸的离解平衡及其与？…

研究了新显色剂２－「２－（５－甲基苯并噻唑）偶氮」－５－二乙氨基苯甲酸（５－Ｍｅ－ＢＴＡＥＢ）的离解平衡及与Ｆｅ＾２＋形成配合物的条件。在十二烷基硫酸钠的存在下,５－Ｍｅ－ＢＴＡＥＢ与Ｆｅ＾２＋形成稳定的蓝紫色２：１配合物,其最大吸收波长为６４０ｎｍ,表观摩尔吸光系数为１．０３＊１０＾５Ｌ．ｍｏｌ＾－１．ｃｍ＾－１。Ｆｅ＾２＋的质量浓度在０－４８０μｇ／Ｌ时服比尔定律。方法用于部级铝合金标样中微量     

钢铁工业废水,含F^—废水与电厂粉煤灰污染与净化的初步试验

本文通过钢铁工业废水淋溶钢铁工业渗漏区土壤，不同ｐＨ值，不同含Ｃａ＾２＋，Ｆ＾－浓度与放心水与工业淋溶各种土壤，以及电厂冲灰水淋溶粉煤灰的三种试验，讨论废水中Ｃ６Ｈ５ＯＨ、ＣＮ＾－ＡＳ、Ｃｒ，Ｐｂ，Ｚｎ，Ｈ２Ｓ，ＢＯＤ，ＣＯＤ，Ｆ＾－，Ｃｌ＾－，ＳＯ＾２－Ｒ，ＮＯ＾－３，ＮＨ＾＋４，Ｎａ＾＋和硬度等的污染与自净规律，并提出了防治地下水污染的措施。     

2-〔2-(6-甲基苯并噻唑)偶氮〕-5-二乙氨基苯甲酸与钴的显色反应及其应用

在十二烷基硫酸钠存在下，于ｐＨ４．８￣７．４的缓冲溶液中，２－〔２－（６－甲基苯并噻唑）偶氮〕－５－二乙氨基苯甲酸（６－Ｍｅ－ＢＴＡＥＢ）与Ｃｏ（Ⅱ）发生显色反应，形成稳定的蓝紫色络合物，其组成为ｎＣｏ（Ⅱ）：ｎ６－Ｍｅ－ＢＴＡＥＢ＝１：２，最大吸收波长为６５０ｎｍ，ε为１．３８×１０＾５Ｌ·ｍｏｌ＾－１·ｃｍ＾－１，Ｃｏ（Ⅱ）质量浓度在０￣０．３２ｍｇ／Ｌ时服从比尔定律。方法可直接用于维生素Ｂ１     

配位滴定法同时测定金属离子浓度的研究

将多元校正分析法应用于配位滴定中，以ＥＤＴＡ为滴定剂，玻璃电极为指示电极，饱和甘汞电极为参比电极。依据电位滴定原理，对混合三组分：Ｃｕ￣（２＋）、Ｃｄ￣（２＋）、Ｚｎ￣（２＋）、及Ｃｕ￣（２＋）、ＣＯ￣（２＋）、Ｎｉ￣（２＋）进行测定，各金属离子之间的△ｌｏｇＫ在０．０４～２．３４之间，计算误差一般小于土１０％。     

钒的交流示波极谱滴定

在有Ｂｒ＾－存在下的ＰＨ５ＨＡｃ－ＮａＡｃ缓冲溶液中，加入过量ＥＤＴＡ，用ＣｕＳｏ４标准溶液滴剩余的ＥＤＴＡ，以Ｃａ＾２＋在交流示波曲线上的切口指示终点。方法简便、准确，可用于矿石中钒的测定。     

硫化物吸附金属离子的实验研究──Ⅰ类型

合成ＰｂＳ、ＺｎＳ对金属离子Ａｇ＋、Ｃｕ（２＋）、Ｃｄ（２＋）、Ｚｎ（２＋）、Ｆｅ（２＋）、Ｍｎ（２＋）、Ｍｇ（２＋）、Ｓｂ（３＋）和Ｂｉ（３＋）的吸附等温线（５０℃）研究表明，其可分为Ａ、Ｂ、Ｃ三类：Ａ类，线性型，即吸附量随吸附离子浓度增加而呈线性上升，并表现出百分之百吸附，属于此类的吸附有ＰｂＳ对Ａｇ＋、Ｃｕ（２＋）离子吸附和ＺｎＳ对Ａｇ＋、Ｃｕ（２＋）、Ｃｄ（２＋）离子的吸附；Ｂ类，朗谬尔型，即随吸附离子的浓度增加，吸附量逐趋向一饱和值，属于此类的有ＰｂＳ对Ｆｅ（２＋）、Ｓｂ（３＋）、Ｂｉ（３＋）等离子及ＺｎＳ对Ｆｅ（２＋）、Ｍｎ（２＋）、Ｍｇ（２＋）等离子的吸附；Ｃ类，反朗谬尔型，即吸附量随吸附离子浓度增加而呈非线性增加。属此类吸附的有ＰｂＳ对Ｚｎ（２＋）、Ｃｄ（２＋）等离子的吸附。合成ＰｂＳ、ＺｎＳ对金属离子的吸附量与天然方铅矿和闪锌矿中微量元素含量可类比，这意味着吸附作用可能在硫化物矿物微量元素形成过程中起着重要的作用。     

Partitioning of Ni2+, Co2+, Fe2+, Mn2+ and Mg2+ between olivine and silicate melts: compositional dependence of partition coefficient

Partitioning of Ni²⁺, Co²⁺, Fe²⁺, Mn²⁺ and Mg²⁺ between olivine and silicate melts has been determined near the join (Mg_0.5·-Fe_0.5)₂SiO₄-K₂O 4SiO₂ and for seven different basaltic compositions. The experiments were made at 1 atm total pressure, 1500-1100°C, and under moderate to reducing oxygen fugacities. The concentration factor, defined as K^MO = (MO)^ol/(MO)^liq (molar ratio), increases markedly for all the cations studied as the olivine component of the liquid decreases. Much of the increase in K^MO is considered as due to the compositional effect of the coexisting liquid: the temperature effect on K^MO is probably opposite to the compositional effect (K^MO decreases as temperature decreases).The partition coefficient K^MO-MgO = (MO/MgO)^ol/(MO/MgO)^liq for the reaction, M_ol²⁺ + Mg_liq²⁺ = M_liq²⁺ + Mg_ol²⁺. is relatively constant over a wide range of SiO₂ content of the liquid, except in the case of Ni²⁺. The partition coefficients have similar ranges both in synthetic and natural rock systems: K^NiO-MgO = 1.8–3.0, K^CoO-MgO = 0.6–0.8, K^FeO-MgO = 0.27–0.38, and K^MnO-MgO = 0.23–0.32. There is a systematic variation in the partition coefficient K^MO-MgO with the composition of liquid; K^MO-MgO increases with increasing SiO₂ content of melt. The partition coefficients for Co²⁺, Fe²⁺ and Mn²⁺ are useful to test the equilibration of olivine with magma of a wide compositional range.     

矿物发光材料CaS∶Mn2+的合成及其荧光性质

以方解石为原料,使用硫化助熔剂法合成了CaS∶Mn2+磷光体,根据荧光光谱,详细探讨了矿物杂质对其发光性质的影响,指出在矿物材料CaS∶Mn2+体系中,某些杂质离子拓宽了基质的激发带,有利于基质吸收能量及基质→Mn2+发射中心的能量传递,但Fe2+、Co2+、Ni2+等离子降低了Mn2+的发射强度,尤其是Mn2+与它们形成的成对离子中心或离子晶簇,降低了局域对称性,放宽了Mn2+跃迁发射的选择定则,加速了材料发光的衰减过程.     

An electrochemical study of Ni2+, Co2+, and Zn2+ ions in melts of composition CaMgSi2O6

Cyclic voltammetry has been done for Ni²⁺, Co²⁺, and Zn²⁺ in melts of diopside composition in the temperature range 1425 to 1575°C. Voltammetric curves for all three ions excellently match theoretical curves for uncomplicated, reversible charge transfer at the Pt electrode. This implies that the neutral metal atoms remain dissolved in the melt. The reference electrode is a form of oxygen electrode. Relative to that reference assigned a reduction potential of 0.00 volt, the values of standard reduction potential for the ions are $\text{E}{}^1\text{(}\text{Ni}{}^{\mathrm{2+}}\text{Ni}{}^0\text{,}\text{diopside}\text{, 1500°C) = ?0.32 ± .01}\text{V}$, $\text{E}{}^1\text{(}\text{Co}{}^{\mathrm{2+}}\text{Co}{}^0\text{,}\text{diopside}\text{, 1500°C) = ?0.45 ± .02}\text{V}$, and $\text{E}{}^1\text{(}\text{Zn}{}^{\mathrm{2+}}\text{Zn}{}^0\text{,}\text{diopside}\text{, 1500°C) = ?0.53 ± .01}\text{V}$. The electrode reactions are rapid, with first order rate constants of the order of 10^?2 cm/sec. Diffusion coefficients were found to be 2.6 × 10^?6 cm²/sec for Ni²⁺, 3.4 × 10^?6 cm²/sec for Co²⁺, and 3.8 × 10^?6 cm²/sec for Zn²⁺ at 1500°C. The value of $\text{E1}$ ($\text{Ni}{}^{\mathrm{2+}}\text{Ni}{}^0$, diopside) is a linear function of temperature over the range studied, with values of ?0.35 V at 1425°C and ?0.29 V at 1575°C. At constant temperature the value of $\text{E}{}^1\text{(}\text{Ni}{}^{\mathrm{2+}}\text{Ni}{}^0\text{, 1525°C}$) was not observed to vary with composition over the range CaO · MgO · 2SiO₂ to CaO·MgO·3SiO₂ or from 1.67 CaO·0.33MgO·2SiO₂ to 0.5 CaO·1.5MgO·2SiO₂. The value for the diffusion coefficient for Ni²⁺ decreased by an order of magnitude at 1525°C over the compositional range CaO · MgO · 1.25SiO₂ to CaO · MgO · 3SiO₂. This is consistent with a mechanism by which Ni²⁺ ions diffuse by moving from one octahedral coordination site to another in the melt, with the same Ni²⁺ species discharging at the cathode regardless of the SiO₂ concentration in the melt.     

Polymerization of silicate and aluminate tetrahedra in glasses,melts and aqueous solutions—II. The network modifying effects of Mg2+ , K+, Na+, Li+, H+, OH−, F−, Cl−, H2O,CO2 and H3O+ on silicate polymers

The effect of the group IA and VIIA ions, as well as Mg²⁺, and the molecules H₂O, CO₂, H₃O⁺ and OH^? on the energy of the Si-O bond in a H₆Si₂O₇ cluster has been calculated using semiempirical molecular orbital calculations (CNDO/2). Three types of elementary processes, i.e. substitution, addition, and polymerization reactions have been used to interpret data on the dynamic viscosity, surface tension and surface charge, hydrolytic weakening, diffusivity, conductivity, freezing point depression, and degree of polymerization of silicates in melts, glasses, and aqueous solutions. As a test of our calculational procedure, observed X-ray emission spectra of binary alkali silicate glasses were compared with calculated electronic spectra. The well known bondlength variations between the bridging bond [Si-O(br)] and the non-bridging bond [Si-O(nbr)] in alkali silicates are shown to be due to the propagation of oscillating bond-energy patterns through the silica framework. A kinetic interpretation of some results of our calculations is given in terms of the Bell-Evans-Polanyi reaction principle.     

Microscope-photometric methods for non-destructive Fe2+ – Fe3+ determination in chloritoids (Fe2+, Mn2+, Mg)2 (Al,Fe3+)4 Si2O10(OH)4

Six natural chloritoid crystals with Fe²⁺ and Fe³⁺ contents ranging from 4.15 to 12.81 and from 0.411 to 0.849g-atoms/l, respectively, as determined by means of microprobe and Mössbauer techniques, served as reference material to develop non-destructive microscope-spectrophotometric methods for quantitative Fe²⁺ – Fe³⁺ determinations in chloritoids from unpolarized spectra of (001) platelets. Fe²⁺ concentrations in g-atom/l can be obtained from [ [Fe³⁺]=C₁xD₁/t where D₁ = log₁₀(I_0/I at 28,000 cm^-1 and t=crystal thickness in cm; C₁ is a conttant that may be influenced somewhat by experimental conditions and is found to be 0.002289 with the experimental set-up used in this study. Fe²⁺ concentrations in g-atom/l can be obtained from [Fe²⁺]=C₁xD₁/D₁-C₃ with D₂=log₁₀(I₀/I) at 16,300 cm^?1 and constants C₄ = 45.36 and C₅ = 3.540. Due to the uncertainties in absorbance measurements, D₁ and D₂ and the thickness measurements, the accuracies are ±0.05 and ±0.15 g-atom/l for [Fe³⁺] and [Fe²⁺], respectively. The determinations may be carried out on chloritoid grains in normal thin sections with an areal resolution of ～10 μm.     

Mg2+ removal in the system Mg2+—amorphous SiO2—H2O by adsorption and Mg-hydroxysilicate precipitation

Two chemical processes can remove Mg²⁺ from suspensions containing amorphous silica (am-SiO₂) at low temperatures: adsorption and precipitation of a Mg-hydroxysilicate resembling sepiolite. Mg²⁺ removal from am-SiO₂ suspensions was investigated, and the relative role of the two removal processes evaluated, as a function of: pH, ionic strength, Mg²⁺ concentration, and temperature.The extent of Mg²⁺ adsorption onto am-SiO₂ decreases with increasing NaCl concentration due to displacement of Mg²⁺ by Na⁺. At NaCl concentrations of 0.05 M and above, adsorption occurs only at pH values above 8.5, where rapid dissolution of am-SiO₂ gives rise to high concentrations of dissolved silica, resulting in supersaturation with respect to sepiolite. Removal of Mg²⁺, at concentrations of 40 to 650 μM, from am-SiO₂ suspensions in 0.70 M NaCl at 25 °C occurs at pH 9.0 and above. Experiments show that under these conditions adsorption and Mg-hydroxysilicate precipitation remove Mg²⁺ at similar rates. For 0.05 M Mg²⁺, at 0.70 M ionic strength and 25 °C, measurable Mg²⁺ removal occurs down to ca. pH 7.5 but is primarily due to Mg-hydroxysilicate precipitation. For the same solution conditions at 5°C, Mg²⁺ removal occurs above pH 8.0 and is primarily due to adsorption.Assuming that increasing pressure does not greatly enhance adsorption, Mg²⁺ adsorption onto am-SiO₂ is an insignificant process in sea water. The surface charge of pristine am-SiO₂ in sea water is primarily controlled by interactions with Na⁺. The principal reaction between Mg²⁺ and am-SiO₂ in marine sediments is sepiolite precipitation.The age distribution of sepiolite in siliceous pelagic sediments is influenced by temperatures of bottom waters and by geothermal gradients.     

Thermodynamic model of natural brines accounting for the presence of trace components: II. System Na+, K+, Mg2+ ‖ Cl?, Br?-H2O

This paper reports the calculations of parameters for the Pitzer equation and thermodynamic potentials of solid phases crystallizing in water-salt systems modeling chloride brines taking into account the presence of bromide ions in them. Solubility diagrams were calculated for corresponding ternary and quaternary systems containing chlorides and bromides of sodium, potassium, and magnesium at 25°C. The results of calculations are in adequate agreement with the available published experimental data on solubility and can be used to model salt crystallization during the concentration of seawater and brines. Original Russian Text ? M.V. Charykova, N.A. Charykov, 2007, published in Geokhimiya, 2007, No. 10, pp. 1129–1138.     

室温常压下 Ca2+-Mg2+-HCO31--H2O 体系的试验研究

世界上很多海域中的现代碳酸盐沉积正在形成,如巴哈马滩、美国的佛罗里达湾、古巴的巴塔诺湾、中东的波斯湾等地,以及丹麦的某些近海地区。产于这些海域中的现代碳酸盐沉积物,其矿物组成主要是文石,其次为镁方解石,纯方解石较少,现代白云石沉积更为少见。我国的现代碳酸盐沉积见于南海诸岛及海南岛的沿海地带。作者曾利用粉晶照相鉴定了采自我国南海二十余种珊瑚、瓣鳃类、腹足类、有孔虫等现代海相生物壳体的物相,发现除有孔虫和海胆壳是由镁方解石构成外,其余生物壳体皆由文石构成。     

溶出珊瑚砂中Ca~(2+)、Mg~(2+)的动力学实验研究及其影响因素

通过改变固液比、摇床转速、珊瑚砂粒径、温度、溶液pH值及溶液含盐量等参数,对珊瑚砂在水溶液中溶出Ca~(2+)、Mg~(2+)进行了实验,以探讨溶出过程中的动力学规律和影响因素。实验结果表明,珊瑚砂中Ca~(2+)、Mg~(2+)溶出量随反应时间逐渐增大;摇床转速越快、固液比越大、温度越高、溶液pH值越低,Ca~(2+)、Mg~(2+)溶出量越大;当珊瑚砂粒径为2.36~4.75 mm、溶液含盐量为100 mg/L时,Ca~(2+)、Mg~(2+)溶出量最大。统计分析表明,摇床转速、温度及溶液p H值均对珊瑚砂溶出有显著影响,但溶液p H值影响最大。珊瑚砂在水中的溶出过程符合收缩核内扩散模型,表明控制整个溶出过程反应速率的决定因素是内扩散速率;在15~40℃时,珊瑚砂在纯水中溶出Ca~(2+)、Mg~(2+)的活化能分别为78.07和74.91 k J/mol。     

铜型蛭石抗菌剂中Cu2+的赋存状态

利用天然矿物蛭石的阳离子交换特点,通过离子交换法将Cu2+植入到蛭石中,制得铜含量高达5.5%(相当于蛭石阳离子交换容量的80%)、具良好抗菌性能的铜型蛭石.经XRD、TEM、AAS分析,结合晶胞参数及晶体化学式的计算,铜型蛭石的XRD特征值更接近于标准的Mg-蛭石,这与Cu2+与Mg2+半径相近、电价相等的特点相符合.Cu2+部分以水合物的形式存在于蛭石层间,部分进入八面体中以六次配位的形式存在.铜型蛭石的a0和b0值无明显变化而c0值略有减小,这对于Cu2+的稳定是有利的.上述各特点有利于铜型蛭石抗菌剂的稳定性和持久性.