Comparison between photocatalytic ozonation and other oxidation processes for the removal of phenols from water

Photocatalytic ozonation (1O₃ + VUV + TiO₂), ozonation (O₃), catalytic ozonation (O₃ + TiO₂), ozone photolysis (O₃ + VUV), photocatalysis (TiO₂ + VUV) and photolysis (VUV) have been compared in terms of formation of intermediates, extent of, mineralization (TOC, COD, chloride, nitrate) and kinetics in the aqueous treatment of three phenols (phenol, p‐chlorophenol and p‐nitrophenol). In all cases, photocatalytic ozonation led to lower degradation times for chemical oxygen demand and total organic carbon removal. Intermediates formed were similar in the different oxidation systems with some exceptions. They can be classified into three different types: polyphenols (resorcinol, catechol, hydroquinone), unsaturated carboxylic acids (maleic and fumaric acids) and saturated carboxylic acids (glyoxylic, formic and oxalic acids). First order kinetic equations have been checked for the oxidation processes studied in the case of the parent compound. Rate constants of these systems have also been calculated. Copyright © 2005 Society of Chemical Industry     

油砂地层中子-伽玛能谱Monte-Carlo模拟

本工作应用自行研制开发的中子 伽玛能谱测井的中子 伽玛射线随空间、能量、时间分布的蒙特卡罗模拟软件包计算了裸眼井、井眼里无下井仪器、油饱和砂岩地层、井眼注油条件下沿井轴和井壁的中子 伽玛射线随能量、时间分布及沿井轴和沿井壁的中子 伽玛射线能谱 ,研究了源距对中子 伽玛射线随能量、时间分布以及井轴与井壁中子 伽玛射线能谱的影响。     

Evaporation and Evolution of Suspended Solution Droplets at Atmospheric and Reduced Pressures

Thermal history and solute precipitation behavior of suspended solution droplets of sodium chloride (NaCl), magnesium sulphate (MgSO₄), and zirconium hydroxychloride (ZrO(OH)Cl) evaporating at atmospheric and reduced pressures are studied. Experimental measurements on the variation of droplet diameter, solution concentration, and temperature during the evaporation period are presented and discussed. The results of solute precipitation behavior in solution droplets observed under an optical microscope are displayed and discussed. Results indicate that reducing the pressure (∼ 33 kPa) results in a change in the solution droplet evaporation rate, but the thermal histories of a particular solution droplet are similar at the atmospheric and reduced pressures. At atmospheric and reduced pressures used in this study, the d² law for solution droplets is valid at early stages of the evaporation and before the solute precipitation initiates. Drying of MgSO₄ and ZrO(OH)Cl solution droplets results in the formation of spherical particles, whereas drying of spherical NaCl solution droplets results in the formation of cubic particles.     

Micro-RBS characterisation of the chemical composition and particulate deposition on pulsed laser deposited Si1−xGex thin films

The formation and deposition of particulates by pulsed laser deposition of Si_1−xGe_x semiconductor alloy thin films are discussed. Using Rutherford backscattering spectrometry with micrometer lateral resolution (micro-RBS) the film composition was measured with high accuracy, even in the presence of particulates with a high areal density of 20,000–30,000 particulates per mm². We show that on impact of a particulate, the part of the thin film which is already deposited probably melts and its Ge content segregates to the surface.     

川东地区长兴组缝洞型储层的识别

本文针对四川东部地区上二叠统长兴组(P_2~2)缝洞型储层的低孔、低渗及非均质性等特点,分析了影响这类储层识别的主要因素,提出了利用现有的地球物理测井手段定性识别储层的指标和定量综合识别储层的方法,这可望提高测试成功率。     

A method of estimating the standard gibbs free energy of formation

Standard Gibbs free energy of formation (ΔG_f⁰), an important property needed in design calculations has been estimated using molar refraction, R_M. The linear relationships derived between ΔG_f⁰ and R_M tested with the data on 8 series of hydrocarbons at 228 compounds yielded average deviations comparable to the methods cited in recent literature. The method can be used as an alternative to the existing ones, because of its simplicity combined with reasonable accuracy.     

Evidence of late palaeozoic thermalwater metallization in South Yongmei Depression

This paper discusses the seafloor thermalwater spout sedimentary activity in South Yongmei Depression according to the following evidences: the Yongmei region was in an extended tectonic environment of metaplateform and locally developed intracontinental rift aulacogen in company with the activity of rich alkali, high potassium volcanics of double-peak type. Several kinds of hydrothermal sedimentary rocks and the ore-bearing sedimentary formations of copper-polymetals, iron and manganese exist in this region with a zoning feature of the seafloor thermalwater spout sedimentation. Project supported by the Science Foundation of NECC for Returns Synopsis of the first author Wu Chengjian, associated professor, born in 1957, majoring in ore deposit and mineralgraphy.     

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本文简要介绍了国外在开发超酸性气体过程中遇到的材料选择、腐蚀监测、水化物堵塞、超酸性气的处理和加工等问题所采取的措施和办法。     

Cu－Zn－Al合金中贝氏体的有序性

本文用Ｘ射线研究了Ｃｕ－２０Ｚｎ－６Ａｌ（ｗｔ％）合金中贝氏体结构的有序性，并与马氏体结构进行了比较，实验表明，从高温Ｂ２母相和低温Ｌ２１母相生成的贝氏体中（１１５）和（２０５）衍射峰或（１２１０）和（２０１０）衍射峰是重叠的，对生成的贝氏体进行一段时间的保温或缓慢冷却处理，其衍射峰的特征并不改变，这与马氏体（１１５）和（２０５）衍射峰或（１２１０）和（２０１０）衍射峰的分离特性不相符合。说明贝氏体结构有序度与马氏体明显不同，它的形成不可能继承母相的有序度。