AgCl比浊法测定软化水中的Cl-

本文采用比浊法来测定软化水中的Cl-含量 ,并对此方法进行了试验 ,证明了采用比较AgCl沉淀的浓度 (颜色 )的方法来测定软化水中的Cl-含量是完全可行的     

水中氯离子含量的准确测定

氯离子是水中普遍存在的一种阴离子，由于它具有较高的克离子极化度，极化后的离子极性和穿透性增强，能明显加速腐蚀反应速度，因此“蒸汽锅炉安全技术监察规程”和“压力容器安全技术监察规程”都规定：“奥氏体受压元件水压试验时，应控制水中的氯离子质量浓度不超过２...     

氯离子对化学需氧量测定的影响

针对较多企业利用氯化方法处理出水的COD测量中氯离子干扰问题,从测定原理、存在的影响、消除效果及适用范围等方面对常用的标准方法进行了实践。结果表明,氯离子对于低浓度COD值影响较大,且不可用曲线扣除法直接得到校正值,因此对于现在较多存在的低浓度COD值高浓度氯离子的样品,用重铬酸钾法直接测定不是十分可行。     

锅水氯离子控制值的计算和探讨

分析了锅水氯离子的影响及其简易计算和控制方法。     

氯离子侵蚀筑坝红土的试验研究

为探索氯离子对红土坝料的破坏机理,设计了化学加速试验,比较了全渗液中铁、铝离子浓度及土样粘粒含量的变化,并分析了土样的微观结构图。试验结果表明,氯离子与筑坝红土中起胶结作用的铁、铝氧化物发生缓慢而长期的化学反应,生成的可溶盐随渗透水流失,降低了红土中胶结物的含量,破坏了红土的结构,进而在坝体内产生了细观渗透通道,降低了土石坝的可靠性和运行寿命。     

基于随机多边形骨料再生混凝土抗氯离子侵蚀研究

基于氯离子扩散模型和骨料级配理论,采用PYTHON语言和COMSOL软件构建再生混凝土随机多边形骨料细观计算模型,并结合已有试验结果验证模型有效性,开展新老砂浆扩散系数、老砂浆厚度及再生骨料取代率等不同工况下再生混凝土抗氯离子侵蚀计算分析,研究氯离子在再生混凝土内部的扩散规律及各细观组分等关键因素对再生混凝土抗氯离子侵蚀的影响规律。结果表明,模拟结果与试验结果吻合较好,该方法能较好地模拟氯离子在再生混凝土内部的扩散过程;再生混凝土氯离子扩散浓度与深度的关系曲线呈现不连续性特征;随着新老砂浆扩散系数的增加,混凝土内氯离子浓度逐渐增大;再生混凝土抗氯离子侵蚀能力随老砂浆厚度、再生骨料取代率的增加而降低。     

杂质氯离子对新型四元硝酸盐腐蚀性的影响

为了探究低氯离子含量（0.01%~0.05%,质量分数）对熔盐与金属材料腐蚀过程的影响,该文采用失重法研究316L不锈钢与氯离子质量分数为0.01%、0.03%、0.05%的混合硝酸盐的腐蚀行为。结果发现,在经过360 h的腐蚀实验后,316L不锈钢在氯离子质量分数为0.03%的熔盐中具有最小的失重量,其为0.4381 mg/cm²。采用SEM、EDS、XRD等方法对316L不锈钢表面形貌进行分析,结果表明,在添加氯离子后不锈钢的腐蚀产物中出现Ca（OH）₂,在Ca（OH）₂的形成过程会消耗氢氧根离子,从而降低了不锈钢失重量。     

气相色谱-质谱法测定水中松节油的研究

研究了吹扫捕集/气相色谱-质谱法测定水中松节油的分析方法,研究表明:低浓度和高浓度标准系列的校准曲线均具有良好的线性关系,相关系数达到0.999,检出限为0.3 μg/L,检出下限为1.2 μg/L,平行重复测定6次,相对标准偏差0.6％～1.8％,加标回收率91.0％～100.2％.该方法简便、灵敏度高,可同时满足废...     

影响水中高锰酸盐指数测定的主要因素研究

高锰酸盐指数是水质监测的一个重要指标,对其测定结果的影响因素进行了探讨,并且给出了较为优化的测定条件。     

控释Ag+饮水消毒技术研究

介绍了含银离子控制释放消毒剂应用的历史、类型、机理、特点及其在废水处理、饮用水净化等各个领域的应用,说明了Ag^＋具有其它消毒剂不可比拟的优点。并对载银离子控制释放消毒技术的前景进行了展望,从而指出了银离子控制释放消毒技术的经济性及其推广的可能性和必然性。     

Investigations on transfer of water and vanadium ions across Nafion membrane in an operating vanadium redox flow battery

Diffusion coefficients of the vanadium ions across Nafion 115 (Dupont) in a vanadium redox flow battery (VRFB) are measured and found to be in the order of V²⁺ > VO²⁺ > VO₂⁺ > V³⁺. It is found that both in self-discharge process and charge-discharge cycles, the concentration difference of vanadium ions between the positive electrolyte (+ve) and negative electrolyte (−ve) is the main reason causing the transfer of vanadium ions across the membrane. In self-discharge process, the transfer of water includes the transfer of vanadium ions with the bound water and the corresponding transfer of protons with the dragged water to balance the charges, and the transfer of water driven by osmosis. In this case, about 75% of the net transfer of water is caused by osmosis. In charge-discharge cycles, except those as mentioned in the case of self-discharge, the transfer of protons with the dragged water across the membrane during the electrode reaction for the formation of internal electric circuit plays the key role in the water transfer. But in the long-term cycles of charge-discharge, the net transfer of water towards +ve is caused by the transfer of vanadium ions with the bound water and the transfer of water driven by osmosis.     

Analysis of Governing Parameters for Silver-Silver Chloride Electrodes in Microfluidic Electrokinetic Devices

Electrokinetics has become a popular method of both particulate and fluidic control in microdevices. In an effort to address the problems associated with conventional electrokinetic control, we use silver-silver chloride electrodes for low-voltage, spatially localized electrokinetic control in microfluidic devices. This work presents an analysis of the electric fields generated by silver-silver chloride electrodes and establishes a nondimensional design parameter that governs the device performance. In addition, an optimal parameter space for maximum electrode longevity is presented.     

Hydrogen evolution using CdWO4 modified by BiFeO3 in the presence of potassium iodide; a combination of photocatalytic and non-photocatalytic water splitting

Novel heterogeneous structure of BiFeO₃–CdWO₄ with different molar ratios was applied for the photocatalytic hydrogen evolution in a self-designed externally UV/visible irradiated photoreactor in the presence of potassium iodide. The photocatalysts were synthesized by simple hydrothermal method and characterized by XRD, FE-SEM-mapping, TEM, UV–Vis DRS, PL, EIS, transient photocurrent and Mott-schottky techniques to identify the structural, optical and photoelectrochemical properties. The slope of Mott-schottky plots confirmed the p-type and n-type conductivity of the synthesized BiFeO₃ and CdWO₄, respectively. The p-n heterojunctions exhibited more efficiently light absorption, charge separation and electron mobility relative to the pure photocatalysts. We observed that coupling 40 mol% BiFeO₃ with CdWO₄ provided the best photocatalytic performance of hydrogen evolution, 268.90 μmol h⁻¹.g_cat⁻¹ from distilled water and 379.43 μmol h⁻¹.g_cat⁻¹ from 0.05 M KI aqueous solution. Iodine species increased H₂ evolution efficiency because of taking part in the charge transfer processes, either by scavenging excited holes or by direct reduction of H⁺ to H^• under UV irradiation. Fermi level equilibrium in the p-n heterojunction suggests the best interparticle charge transfer mechanism explaining how photoinduced electrons with superior energy states and desirable lifetime can be supplied to reduce H⁺ to H^•.     

The influence of metal ions on the conductivity of Nafion 112 in polymer electrolyte membrane fuel cell

Nafion 112 membranes were soaked in 1 M H₂SO₄ solutions containing variable amounts of Fe and Cr ions, either individually or mixed. An even distribution of the metal ions on the surface of the membranes was observed with electron probe microanalysis (EPMA) mapping. The proton conductivity of the soaked membranes was investigated using a conductivity cell. For Fe ions, the conductivity was almost constant until the Fe-ion solution concentration reached 300 ppm. Over the 300-ppm threshold, the conductivity decreased significantly. Similar results were obtained with Cr ions in the membrane, but here the threshold was approximately 200 ppm in the solution. Mixed metal ions were found to decrease these threshold values due to the additive effect of the two metals.     

A novel method for generating hydrogen by hydrolysis of highly activated aluminum nanoparticles in pure water

A simple method with 100% efficiency for generating pure hydrogen in large scale by hydrolysis of highly activated aluminum in water was established. In this activation method, Aluminum is milled using salt particles (as nano-miller) with different salt to aluminum mole ratios. Due to their brittle nature, salt particles are fractured during milling and their sharp edges chop aluminum particles into pieces. This leads to an increment in hydrolysis kinetics. Meantime, salt particles are driven into newly created surfaces of aluminum particles, producing salt gates that will be removed in water environment, causing hydrogen generation reaction to proceed. The other product of reaction is aluminum oxide hydroxide (AlOOH) which is nature-friendly and can be easily separated from water. The highest average rate of hydrogen generation was 75 ml/min per 1 g of aluminum.     

烟气汞形态分布及其受氯化物添加剂影响的研究

在自行设计的一维煤粉燃烧试验台上,研究了烟气汞形态的分布特征,并分析了NaCl作为添加剂与煤混烧对汞形态分布的影响.结果表明:在试验煤种烟气中,气态汞是烟气汞最主要的排放形式,二价汞是气态汞的主要形式,飞灰中的汞含量比底渣中的汞舍量高;NaCl的添加使气态二价汞和单质汞占总汞的百分比都有不同程度的下降,而颗粒态汞的比例相应增加,但随着NaCl添加量的增加,颗粒态汞的增加量逐渐趋于平缓,单质汞的减少量也相应降低,趋势趋于平缓.     

Study on Adsorption of Water in MCM41 Containing Metal Ions by Molecular Dynamic Simulations

To clarify whether the adsorption of water in MCM41 can be promoted by introducing some metal ions onto its surface, molecular dynamics simulations were carried out to investigate the behavior of some water molecules confined in mesoporous MCM41 whose pore size was tailored to 2.5 nm. Pure silica MCM41 as well as those containing some metal ions such as Al3 , Cu2 , and La3 was simulated, and by observing the local average density distribution of particles, we found that both the MCM41 containing Al3 and that of La3 performed higher adsorption and lower desorption temperature. It is concluded that the adsorption is improved mainly owing to the diversities of polarity, active sites, and structure imported by these metal ions.     

常用采油助剂对原油有机氯含量影响分析

原油中的有机氯主要来源于油田开发过程中使用的各种油田化学药剂,原油中有机氯含量升高,对原油品质和后续加工的影响极大。按照Q/SHCG 39—2012《油田化学剂中有机氯含量测量方法》,对采油药剂中有机氯含量进行测定。同时,选取四个典型区块,按照GB 18612—2011《原油有机氯含量的测定方法》,实验室模拟现场加药情况,考察了单种不同类型药剂及多种药剂共同作用时对原油有机氯含量的影响。结果显示,采油助剂的有机氯含量对原油的有机氯含量影响明显,特别是油溶性采油助剂,大部分有机氯可转移至原油中,使原油中的有机氯含量增加,导致后续加工工序复杂。因此,要彻底避免原油开采过程中混入有机氯,必须限制或限量使用各类含有有机氯的油田化学助剂,尤其是含有有机氯的油溶性采油助剂。目前,胜利油田根据药剂使用以及与原油接触情况,基本消除了原油处理以及水处理等化学药剂中的有机氯含量。