Selective inhibition of nitrite oxidation by chlorate dosing in aerobic granules

Partial nitrification was successfully achieved with addition of 5mM KClO(3) in the aerobic granules system. Batch tests demonstrated that KClO(3) selectively inhibited nitrite-oxidizing bacteria (NOB) but not ammonia-oxidizing bacteria (AOB). During stable partial nitrification, the influent pH was kept at 7.8-8.2, while the DO and temperature were not controlled in the SBR. When the NH(4)-N and COD levels were kept at 100mg/l and 400mg/l in the influent, the NH(4)-N and COD removal efficiencies reached 98.93% and 78.65%, respectively. The NO(2)-N accounted for 92.95% of the NO(χ)-N (NO(2)-N+NO(3)-N) in the effluent. Furthermore, about 90% of the chlorate was reduced to nontoxic chloride, thus it would not cause environmental problem. SEM showed that the main composition of the aerobic granules was bacilli and coccus bacteria. FISH analysis revealed that AOB became the dominant nitrifying bacteria, whereas NOB were detected only in low abundance. Chlorate could be used to control the development and maintenance of aerobic granules sludge for partial nitrification.     

Combined Computational and Experimental Study on the Adsorption and Inhibition Effects of N2O2 Schiff Base on the Corrosion of API 5L Grade B Steel in 1 mol/L HCI

The electrochemical behavior of low carbon steel （API 5L grade B） in 1 mol/L HCI solution with different concentrations of N,Nr-bis（4-formylphenol）-trimethylenediamine Schiff base was studied by electrochemical techniques and density functional theory analysis. The inhibition efficiency was found to increase with increasing inhibitor concentration and decreased with increasing temperature. The high inhibition efficiency was attributed to the blocking of active sites by adsorption of inhibitor molecules on the steel surface. Thermodynamic parameters for the adsorption and activation processes were determined. Galvanostatic polarization data indicated that Schiff base act as a mixed-type inhibitor and the adsorption isotherm obeyed the Langmuir adsorption isotherm. Results obtained from quantum chemical studies show excellent correlations between the quantum chemical parameters and the experimental inhibition efficiencies using density functional theory at the B3LYP/6-31G（d,p） and B3LYP/3-21G basis set levels and ab initio calculations using HF/6-31G（d,p） and HF/3-21G methods.     

碳酸盐岩储层酸化液添加剂综述

介绍了酸化作业中使用的一些主要添加剂如增稠剂、缓蚀剂、酸缓速剂、铁稳定剂、粘土稳定剂及降滤失剂、酸液助排剂等产品的种类、性能特点及其国内外研究现状和发展动向。指出许多酸化液添加剂都在朝着耐温、抗盐、无地层损害的方向发展,提高强化处理效果。     

百色油田油井结蜡及清防蜡处理

本文了滇黔桂百色油田的严重结蜡情况，清防蜡剂的筛选，使用筛选出的防蜡剂ＪＳ２进行油清防蜡处理的工艺方法和效果。自１９９０年１０月起，在百色油田各区块６２口油井采用不停产加入油套环空，加入后关井或在油套管间循环２－４小时，挤入油层等方法进行的清防蜡作业，除井温过低的一个井外，全部获得成功。     

新型钢筋阻锈剂的合成及其阻锈性能的研究

合成了一种舍有氨基和菝基的有机阻锈刑，并用硬化砂浆法研究了该阻锈剂在砂浆中含有氯离子的条件下对钢筋锈蚀的抑制作用，同时与常用的亚硝酸盐的阻锈效果进行了比较。结果表明，该新型阻锈剂能够有效地阻止钢筋表面钝化膜的破坏，比亚硝酸盐具有更好的阻锈效果。     

γ辐照TBP-正十二烷体系酸性长链磷酸酯的抑制

本文通过元素分析,IR谱及MS谱等方法研究了TBP—正十二烷体系中酸性强络合辐解产物的性质和结构。用同位素示踪方法对长链酸性磷酸酯的生成机理进行了探讨并找到了能抑制长链酸性磷酸酯的有效的抑制剂。     

汽车防冻液中的缓蚀剂与稳定剂

对近十年来防冻液的专利进行了综合介绍,阐述了内燃机冷却系统使用的防冻液的主要组分缓蚀剂和稳定剂的组成及复配方法,简单介绍了我们研究的防冻液的性质及使用情况。     

一步法合成丙烯酸－β－羟乙酯新工艺研究

研究了一步合成丙烯酸－β－羟乙酯的新工艺。优化了工艺条件；改进了提纯工艺，并对阻聚剂进行了筛选。     

Effect of calcium nitrite-based corrosion inhibitor in preventing corrosion of embedded steel in concrete

Due to the corrosion inhibition effect and compatibility with concrete properties, calcium nitrite solution has been widely used, in North America and Asia,. However, investigation has often been restricted to tests using a macrocell corrosion monitoring or measuring corrosion rate in an aqueous condition. This study concerns the assessment of the inhibition effect of calcium nitrite-based corrosion inhibitor using a polarisation method and its influence on the chloride transport, compressive strength and setting time of concrete.The calcium nitrite-based corrosion inhibitor significantly reduced the corrosion rate of steel in chloride contaminated mortar and raised the chloride threshold level, ranging from 0.22% to 1.95% by weight of cement, while nitrite-free specimen produced the threshold level ranging from 0.18% to 0.33%. It was observed that concrete specimens containing the corrosion inhibitor produced the higher total charge passed in a rapid test for chloride ion permeability. An increase in the dosage of corrosion inhibitor resulted in a decrease in the concrete setting time. In addition, the compressive strength at early ages was increased by corrosion inhibitor, but in a long term (900 days), decreased to the level for 28 days.     

Phytate as efficient and green corrosion inhibitor for NdFeB magnets in aqueous salt solution

Phytate had been investigated as a corrosion inhibitor for NdFeB magnets in an aqueous salt solution. Potentiodynamic polarisation, electrochemical impedance spectroscopy, X-ray photoelectron spectroscopy, scanning electron microscopy and energy dispersive spectroscopy were employed for this investigation. The polarisation curves results revealed that phytate acted as a mixed type inhibitor. The inhibition efficiency was found to increase by maximum 96.5% through increasing the phytate concentration to 0.5?mM at 30°C. The inhibition was proposed to result from the adsorption of phytate on NdFeB magnets, which was found to obey the Langmuir adsorption isotherm. The inhibition mechanism was explored by the potential of zero charge (E_pzc) measurement at the solution/metal interface.