芳香族醛酮化合物溶解度和分配系数的测定与估算

本文测定了１５种芳香族醛酮化合物的溶解度和正辛醇－水分配系数,研究了水溶解度及分配系数与分子连接性能指数的相关性。结果表明,溶解度和分配系数之间以及与分子连接性指数呈较好的线性关系。     

光子相关光谱（PCS）在无机高分子絮凝剂形态表征中的应用

本文运用现代先进的微粒检测手段光子相关光谱对常见的两类无机高分子絮凝剂的形态进行了表征。实验结果表明：在所测聚合氯化铁溶液中，体系呈较为单一的集中分布，由平移扩散系数计算得到平均有效直径在５－１１ｎｍ左右。在所测聚合氯化铝溶液中，主要为双峰分布，熟化后样品约为２－５ｎｍ的小颗粒与数十ｎｍ以上分布较宽的聚集体，另外，本文对光子相关光谱在形态表征中的优缺点及其它应用的可能性也作了一定的论述。     

Field studies on 32P movement and P leaching from flooded paddy soils in the region of Taihu Lake, China

Field experiments were done in two sites, Yixing and Changshu, Jiangsu province, China, to study P movement and leaching in flooded paddy soils. P movement in soil was investigated by using the KH2 32PO4 tracker method, and the amount of P leached from the soil layer in different depths was estimated by measuring P concentrations in the soil solution and saturated hydraulic conductivities in field. Determination was done about one month after P application. There was 46% and 42% of total 32P retained in the 0-5cm layer of soil in the Yixing site and in the Changshu site respectively. The 32P retained in the 25-30 cm layer was only about 1-2% of the total 32P added. Furthermore, 8.01% of 32P in the soil of Yixing site and 16.8% of 32P in the soil of Changshu site was lost from the layer 0-30 cm soil. The seasonal amounts of P leached from the top soil layer and from bottom layer are about 4.5-5.8% and 1.6-2.1% of the total P application, respectively. Changes of total P concentrations in soil solutions during rice growth showed that the fertilizer P applied before flooding of the paddy fields suffered a flash leaching loss and a slow leaching loss. We concluded that the fertilizer P could quickly move in the flooded paddy rice field and parts of it can enter into surface water and ground water. Unless the P application is well managed the risk of P loss and consequently environmental pollution exist.     

The gas-photocatalytic degradation of trichloroethylene without water

The photocatalytic degradation of gaseous trichloroethylene (TCE) without water has been studied. The degradation products were determined to be CO₂, HCl and Cl₂, and the reaction stoichiometry, was described as

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. The degradation rate was found to be linear with 0.16 power of the illumination intensity. When the TCE concentration was low (10¹⁴ mol L⁻¹ or a little more), its degradation rate model could be considered as first order kinetics. A mechanism of valence band hole oxidation was proposed.     

水解酸化-SBR工艺处理果汁废水的研究

采用水解酸化-SBR工艺，对浓缩果汁生产废水处理进行了试验研究，结果表明：当进水COD浓度为3 500～5 000 mg/L，pH为6.5～7.5，在水解酸化池水力停留时间为8 h，SBR反应池MLSS浓度3 500～4 000 mg/L，进水15 min，曝气7 h，沉淀1 h，出水15 min的条件下，出水COD去除率保持在97％以上，SS去除率达93％以上。且以水解酸化作为预处理单元可去除果汁废水中的SS达78％以上，为后续SBR工艺的稳定运行创造有利条件，提高组合工艺的整体效果。     

Effects of redox potential and pH value on the release of rare earth elements from soil

Equilibrium release experiments were conducted under three different pH values of 3.5, 5.5 and 7.5 as well as three redox potentials of 400, 0 and -100 Mv to investigate the influence of redox potential and pH value on the La, Ce, Gd and Y release of from the simulated-REEs-accumulation (SRA) soil. Oxygen and nitrogen were allowed to flow into soil suspension to adjust redox potential to a preset value, and 1 mol/l HCl or 1 mol/l NaOH solutions were added into the soil suspension to keep pH at a preset value. Results indicated that La, Ce, Gd and Y release increased gradually with the decrease of pH value or Eh, and the influence of redox potential on Ce was more remarkable than on La, Gd and Y. At the same time. It was observed that La, Ce, Gd and Y releases were positively correlated with the release of Fe and Mn, indicating that La, Ce, Gd and Y releases might originate from dissolution of Fe-Mn oxyhydroxides under reduction and low pH conditions. Moreover, it was found that alteration of pH value and redox potential might affect the change of La, Ce, Gd and Y species in the soil. The contents of La, Ce, Gd and Y in exchangeable fraction and Fe-Mn oxide fraction in the solid phase from soil suspension separation decreased with the decline of pH value and redox potential. Multiple stepwise regression analysis showed that exchangeable fraction and Fe-Mn oxide fraction predominately contributed to the La, Ce, Gd and Y release. Low pH value and redox potential were more favorable to La, Ce, Gd and Y releases following the change of their species. The La, Ce, Gd and Y contents in exchangeable fraction and Fe-Mn oxide fraction are the main contributors to their release.     

Distribution of mercury in the combustion products from coal-fired power plants in Guizhou,southwest China

Method 30B and the Ontario Hydro Method (OHM) were used to sample the mercury in the flue gas discharged from the seven power plants in Guizhou Province, southwest China. In order to investigate the mercury migration and transformation during coal combustion and pollution control process, the contents of mercury in coal samples, bottom ash, fly ash, and gypsum were measured. The mercury in the flue gas released into the atmosphere mainly existed in the form of Hg°. The precipitator shows a superior ability to remove Hg^p (particulate mercury) from flue gas. The removal efficiency of Hg²⁺ by wet flue gas desulfurization (WFGD) was significantly higher than that for the other two forms of mercury. The synergistic removal efficiency of mercury by the air pollution control devices (APCDs) installed in the studied power plants is 66.69–97.56%. The Hg mass balance for the tested seven coal-fired power plants varied from 72.87% to 109.67% during the sampling time. After flue gas flowing through APCDs, most of the mercury in coal was enriched in fly ash and gypsum, with only a small portion released into the atmosphere with the flue gas. The maximum discharge source of Hg for power plants was fly ash and gypsum instead of Hg emitted with flue gas through the chimney into the atmosphere. With the continuous upgrading of APCDs, more and more mercury will be enriched in fly ash and gypsum. Extra attention should be paid to the re-release of mercury from the reutilization of by-products from APCDs.

Implications: Method 30B and the Ontario Hydro Method (OHM) were used to test the mercury concentration in the flue gas discharged from seven power plants in Guizhou Province, China. The concentrations of mercury in coal samples, bottom ash, fly ash, and gypsum were also measured. By comparison of the mercury content of different products, we found that the maximum discharge source of Hg for power plants was fly ash and gypsum, instead of Hg emitted with flue gas through the chimney into the atmosphere. With the continuous upgrading of APCDs, more and more mercury will be enriched in fly ash and gypsum. Extra attention should be paid to the re-release of mercury from the reutilization of by-products from APCDs.     

利用有机质发酵产氢的影响因素与应用前景

煤、石油等化石能源的紧缺,使得氢气等可再生能源的开发与利用备受关注.生物制氢技术由于在获得清洁能源氢气的同时,还使得大量有机废弃物得到处理或净化,从而使得该技术成为当前研究的热点.总结了发酵产氢的微生物种类及产氢基质,阐述了不同有机物种类的发酵产氢机理,综述了温度、pH值、金属离子、气相条件及氧化还原电位等生态因子对发酵产氢的影响,并论述了生物制氢技术的发展方向和应用前景.     

鞍山市生态环境遥感评价指标体系

文中应用卫星遥感数据，通过选取合适的评价指标，建立适合本地区的生态环境质量监测与评价指标系统。为开发环境资源和建设生态环境提供管理和决策的依据。     

上海市NOx分布状况及其影响因素

以一种简易可靠的大气ＮＯｘ测量方法，大范围地调查了上海市区的ＮＯｘ浓度状况。结果表明，上海市ＮＯｘ浓度分面状况，在不同性质的街区，不同地段，不同道路之间，存在明显差异，居民区大气中ＮＯｘ的浓度可达到国家一级标准要求，但市区各道路网超标严重，平均是一级标准的１．７倍，道路网ＮＯｘ的分布总体呈东南低，北和西北高的梯次。影响城市ＮＯｘ浓度分布的主要因素有：交通、风力、地形、绿化等，在城市建设规划时，应充