基于RS和GIS的西部干旱区生态环境调控研究

实现生态环境优化调控与科学管理，是保护生态环境、促进社会经济与环境协调发展、建立人与自然和谐关系的重要举措。尤其是对生态环境十分脆弱的西部干旱地区，各级政府和学术界给予高度的重视。在定量研究生态环境调控的理论方法和具体操作过程中，需要借助遥感(RS)、地理信息系统(GIS)以及它们的结合等技术手段，来实现时空变化信息的实时、动态监测以及信息的提取、分析和处理。本文针对西部干旱区生态环境调控问题。提出一种RS和GIS支持下的生态环境调控量化研究方法，包括基于RS和GIS的西部干旱区生态环境量化指标体系、生态环境调控管理模型、调控方案优选与实施。并介绍一个应用例子。     

汕头港湾附近水域潮流特征和污染物扩散的数值计算 Ⅱ.汕头港湾附近水域污染物的扩散数值模拟

本文在对汕头港湾附近水域的潮流特征进行数值模拟并获得了潮流和余流场分布信息的基础上，通过特定排放源的数值模拟，研究了该水域污染扩散条件及输运规律。     

钢铁厂废水中有机污染物组成分析

采用GDX-502树脂富集等前处理方法。毛细管气相色谱和色—质联用等检测手段,分析钢铁厂废水有机污染物组成。定性出以芳烃类、酚类为主的73种有机污染物。采用多污染物环境影响评价系统,就其有机污染物对人体健康和生态的潜在危害进行了初步评价。结果表明,甲酚、萘、苯、酚是危害人体健康和生态的主要污染物。     

Degradation of sulfonamides and formation of trihalomethanes by chlorination after pre-oxidation with Fe(Ⅵ)

Sulfonamides are used in human therapy,animal husbandry and agriculture but are not easily biodegradable,and are often detected in surface water.Sulfamethazine(SMZ) and sulfadiazine(SDZ) are two widely used sulfonamide antibiotics that are used heavily in agriculture.In this study,they were degraded in an aqueous system by chlorination after pre-oxidation with ferrate(VI)(FeVIO42-,Fe(VI)),an environmentally friendly oxidation technique that has been shown to be effective in degrading various organics.The kinetics of the degradation were determined as a function of Fe(VI)(0–1.5 mg/L),free chlorine(0–1.8 mg/L) and temperature(15–35°C).According to the experimental results,SMZ chlorination followed second-order kinetics with increasing Fe(VI) dosage,and the effect of the initial free chlorine concentration on the reaction kinetics with pre-oxidation by Fe(VI) fitted a pseudo-first order model.The rate constants of SDZ and SMZ chlorination at different temperatures were related to the Arrhenius equation.Fe(VI) could reduce the levels of THMs formed and the toxicity of the sulfonamide degradation systems with Fe(VI) doses of 0.5–1.5 mg/L,which provides a reference for ensuring water quality in drinking water systems.     

Preparation, characterization and performance of poly(m-phenylene isophthalamide)/organically modified montmorillonite nanocomposite membranes in removal of perfluorooctane sulfonate

Nanocomposite membranes containing poly(m-phenylene isophthalamide) (PMIA) and organically modified montmorillonite (OMMT) were prepared by a combination of solution dispersion and wet-phase inversion methods, and the effects of OMMT addition on the properties and performance of fabricated nanofiltration membranes were investigated. The membranes were characterized by contact angle measurements, scanning electron microscopy (SEM), atomic force microscopy (AFM), thermogravimetric analysis, and zeta potential. The performance of the membranes was elucidated by the removal of perfluorooctane sulfonate (PFOS) at neutral pH. Increasing OMMT concentration improved the thermal stability and hydrophilicity of the membranes. The permeation and rejection of PFOS were significantly improved. The performance of fabricated nanofiltration membranes in removal of PFOS varied depending on the solute and membrane properties as well as solution conditions. Finally, a comparison between fabricated membranes and a commercial NF membrane (ESNA1-K1, Hydecanme) proved that the OMMT addition is a convenient procedure for producing nanocomposite membranes with superior properties and performance.     

SO2及PM10污染频次分析方法的探讨

以梅州为例,对城区小区域内3个站点的SO₂及PM₁₀浓度进行统计,分析SO₂及PM₁₀浓度变化的发生偏离正常水平的时间分布情况,为大气污染防治工作提出决策支持建议。     

铜、锌对小麦的联合毒性及其预测模型研究

利用溶液培养实验,研究了不同Ca浓度和Cu/Zn配比下,Cu、Zn对小麦的联合毒性;基于毒性单位模型(TU)和生物配体模型(BLM),建立了Cu-Zn对小麦的联合毒性预测模型TUfmix-BLM.结果表明,随着溶液中Ca浓度增加,单一Cu和Zn的毒性均明显减弱.不同Ca浓度、不同Cu/Zn浓度配比下(1∶50、1∶200、1∶800),Cu-Zn联合毒性均表现为加和作用.基于Cu、Zn单一毒性的BLM络合常数,结合TU模型,预测了CuZn对小麦的联合毒性.与单独利用TU模型相比,TUfmix-BLM预测的RMSE从13.06减小到10.01,R2从0.89增加到0.94,表明TUfmix-BLM模型可以很好地预测Cu-Zn的联合毒性.     

Application of polyacrylamide to reduce phosphorus losses from a Chinese purple soil: A laboratory and field investigation

Use of anionic polyacrylamide (PAM) to control phosphorus (P) losses from a Chinese purple soil was studied in both a laboratory soil column experiment and a field plot experiment on a steep slope (27%). Treatments in the column study were a control, and PAM mixed uniformly into the soil at rates of 0.02, 0.05, 0.08, 0.10, and 0.20%. We found that PAM had an important inhibitory effect on vertical P transport in the soil columns, with the 0.20% PAM treatment having the greatest significant reduction in leachate soluble P concentrations and losses resulting from nine leaching periods. Field experiments were conducted on 5 m wide by 21 m long natural rainfall plots, that allowed collection of both surface runoff and subsurface drainage water. Wheat was planted and grown on all plots with typical fertilizer applied. Treatments included a control, dry PAM at 3.9 kg ha^?1, dry PAM at 3.9 kg ha^?1 applied together with lime (CaCO₃ at 4.9 t ha^?1), and dry PAM at 3.9 kg ha^?1 applied together with gypsum (CaSO₄·2H₂O at 4 t ha^?1). Results from the field plot experiment in which 5 rainfall events resulted in measurable runoff and leachate showed that all PAM treatments significantly reduced runoff volume and total P losses in surface runoff compared to the control. The PAM treatments also all significantly reduced water volume leached to the tile drain. However, total P losses in the leachate water were not significantly different due to the treatments, perhaps due to the low PAM soil surface application rate and/or high experimental variability. The PAM alone treatment resulted in the greatest wheat growth as indicated by the plant growth indexes of wheat plant height, leaf length, leaf width, grain number per head, and dried grain mass. Growth indexes of the PAM with Calcium treatments were significantly lesser. These results indicate that the selection and use of soil amendments need to be carefully determined based upon the most important management goal at a particular site (runoff/nutrient loss control, enhanced plant growth, or a combination).     

Phenanthrene adsorption on soils from the Yangtze River Delta region under different pH and temperature conditions

Environmental Geochemistry and Health - The phenanthrene (PHE) adsorption on soils from the Yangtze River Delta region under different pH and temperature conditions was studied in the laboratory....     

基于电磁感应和位移传感原理的电梯门锁啮合长度检测研究

电梯门锁锁紧元件啮合状态可靠性是确保电梯门系统安全运行的重要保障。针对现有电梯门锁啮合长度检验方法存在的测量精度不足、自动化程度低、通用性不强等问题,提出了一种基于传感器的检测方法。分析了电磁感应开关通断检测原理和接触式位移传感工作原理,在此基础上开发了门锁啮合长度检測装置,并介绍了使用该装置的检验步骤。实测结果表明:该检验方法和检验装置可以实现门锁啮合长度的快速准确检验,数据可重复性高。