Sorption and desorption of glyphosate,MCPA and tetracycline and their mixtures in soil as influenced by phosphate

Phosphate fertilizers and herbicides such as glyphosate and MCPA are commonly applied to agricultural land, and antibiotics such as tetracycline have been detected in soils following the application of livestock manures and biosolids to agricultural land. Utilizing a range of batch equilibrium experiments, this research examined the competitive sorption interactions of these chemicals in soil. Soil samples (0-15 cm) collected from long-term experimental plots contained Olsen P concentrations in the typical (13 to 20 mg kg^?1) and elevated (81 to 99 mg kg^?1) range of build-up phosphate in agricultural soils. The elevated Olsen P concentrations in field soils significantly reduced glyphosate sorption up to 50%, but had no significant impact on MCPA and tetracycline sorption. Fresh phosphate additions in the laboratory, introduced to soil prior to, or at the same time with the other chemical applications, had a greater impact on reducing glyphosate sorption (up to 45%) than on reducing tetracycline (up to 13%) and MCPA (up to 8%) sorption. The impact of fresh phosphate additions on the desorption of these three chemicals was also statistically significant, but numerically very small namely < 1% for glyphosate and tetracycline and 3% for MCPA. The presence of MCPA significantly reduced sorption and increased desorption of glyphosate, but only when MCPA was present at concentrations much greater than environmentally relevant and there was no phosphate added to the MCPA solution. Tetracycline addition had no significant effect on glyphosate sorption and desorption in soil. For the four chemicals studied, we conclude that when mixtures of phosphate, herbicides and antibiotics are present in soil, the greatest influence of their competitive interactions is phosphate decreasing glyphosate sorption and the presence of phosphate in solution lessens the potential impact of MCPA on glyphosate sorption. The presence of chemical mixtures in soil solution has an overall greater impact on the sorption than desorption of individual organic chemicals in soil.     

关于节能减排达标申报制度的信号博弈分析

恰到好处的奖罚制度是促成企业自觉环保或者监管机构积极监理的前提。特别地,为促成企业自觉地采取环保行动,必须加大针对监管机构不作为的惩戒力度,而不仅仅是进一步地提高针对企业环保行为的奖罚力度。这就给环境监管机构带来了莫大的压力。因此,为有效缓解监管机构的工作压力,有必要建立节能减排达标申报制度。基于节能减排达标申报制度的信号博弈分析,排放达标企业将如实申报自己的节能减排情况。但只要监管机构对于申报排放达标企业意思表示真实的信心足够高,排放未达标的企业就有动机虚假申报其节能减排的情况。因此,节能减排达标申报制度存在四种可能的运行状况,亦即存在四种可能的后继博弈精炼Bayes Nash均衡策略。其中的两个为分离均衡状态,另外两个则为混同于申报达标的均衡状态。两个混同均衡的效果极差,实际上意味着节能减排达标申报制度失效。只有在分离均衡1或2下,节能减排达标申报制度的运行才较为理想。而且分离均衡2的效果要优于分离均衡1。因此,建议完善现行的排污申报与登记制度,建立节能减排达标申报制度。并尽可能地加大针对达标企业的财政补贴力度以及针对未达标企业的惩罚力度,以便尽可能地降低节能减排达标企业错误申报的可能性。与此同时,还要严格政府监管机构的组织纪律,除了要求全面核查申报达标的企业,并加大针对政府监管机构不作为的惩戒力度之外,还应经由全面核查,对节能减排达标企业的环保工作评定等级,以便重奖优者。     

马三峰土质边坡稳定性分析与评价

基于马三峰边坡南段土质边坡的工程地质特征现场勘查,分别运用极限平衡法和快速拉格朗日法分析了马三峰土坡的稳定性,搜索出了潜在的滑动面并计算出相应的安全系数,结果认为土坡整体是不稳定的。通过2种计算结果的对比研究,对此土坡的破坏模式及其发展趋势做出评价,认为此土质边坡破坏的力学特征为牵引式滑坡,失稳不是一次性地全部滑塌,而是分阶段滑动,破坏模式为一系列动态的平面—圆弧滑面破坏。如不及时治理,该滑坡体将会继续向后缘发展。     

钢渣吸附除磷性能的试验研究

研究了钢渣的吸附除磷效果并进行机理探讨。结果表明：钢渣采用0．5g,即可在25℃下、2个小时内,将100ml的磷浓度为10mg／L（以磷计）的模拟含磷废水的磷浓度降至0．5mg／L以下,达到磷的国家一级排放标准;钢渣吸附平衡时问为2小时;钢渣吸附除磷的机理主要是沉淀、吸附（表面络合反应）,并辅以静电作用。     

餐饮源气相与颗粒相多环芳烃排放特征

多环芳烃(PAHs)是导致大气二次污染严重和臭氧浓度高的原因之一.通过对深圳市3家商业性餐馆和1家食品加工厂的采样调查,分析对比了我国主要中式餐饮源排放的PAHs在气相和颗粒相之间的差异,也重点关注了餐饮源烷基PAHs的排放特征.结果表明,食品加工厂排放的颗粒相和气相ρ(总PAHs)为(1 381.6±140.5)ng...     

Combating dye pollution using cocoa pod husks: a sustainable approach

The adsorptive potential of activated carbon prepared by chemical activation of Cocoa pod husk (CPHAA) to remove Congo red (CR) dye from its aqueous solution was investigated in this study. CPHAA was characterised using Energy Dispersive X-Ray, Scanning Electron Micrograph and Fourier Transform Infrared Spectroscopy techniques. The effects of contact time, initial dye concentration, pH and solution temperature were studied. Equilibrium data were fitted to Langmuir, Freundlich, Temkin and Dubinin–Radushkevich isotherm models. The equilibrium data were best represented by Langmuir isotherm model, with maximum monolayer adsorption capacity of 43.67 mg/g. The kinetic data were fitted to Pseudo-first-order, Pseudo-second-order, Elovich and Intraparticle diffusion models; the pseudo-second-order kinetic model provided the best correlation. Thermodynamic parameters such as standard enthalpy (ΔH^o), standard entropy (ΔS^o) and standard free energy (ΔG^o) were evaluated. The thermodynamic study showed that the process is endothermic, spontaneous and feasible. The mean free energy of adsorption shows that the mechanism is by physisorption. CPHAA was found to be an effective adsorbent for the removal of CR dye from aqueous solution.     

航空运输安全监管的博弈分析

针对我国航空运输安全监管的现状,应用博弈论建立航空运输安全生产监管的博弈模型,探讨航空运输安全监管制度的内在机理,对航空公司与安全监管部门之间博弈关系的策略集进行深入分析,并给出了博弈模型的纯策略和混合策略纳什均衡的求解与分析,最后给出了航空运输安全生产监管的对策与建议,为我国航空运输安全监管制度的健康发展提供了有益的启示,同时为我国航空运输安全监管体制建设提供了理论依据。     

发展循环经济的低碳综合集成模式

根据循环经济内涵特征,透析循环经济指标体系,判明循环经济低碳品质,阐述循环经济理论困境;针对循环经济发展现状,从节能减排、能源结构、产业模式三个维度诊断循环经济实践困境;在此基础上,提出循环经济低碳模式;以综合集成视角,从整体特性、模式结构和运行模式三个角度分析循环经济低碳综合集成模式的系统特征;从理论基础、理论体系和理论创新三个角度构建低碳模式的综合集成理论框架。低碳模式是针对化石能源利用高碳排放问题,以提高碳生产率实现可持续发展为发展目标,以能源消费和废弃物减量化排放为发展原则,以"低能耗、低排放、低污染"和"高效能、高效率、高效益"为基本特征,以能源结构调整、产业模式优化和技术体系创新为主要手段,以节能减排为发展方式,以低碳政策体系为重要保障的特殊循环经济模式。实施低碳模式是一项复杂的系统工程,其通过构筑低碳均衡达到"社会-经济-生态"的可持续发展。     

General equilibrium effects of a supply side GHG mitigation option under the Clean Development Mechanism

The Clean Development Mechanism (CDM) under the Kyoto Protocol to the United Nations Framework Convention on Climate Change is considered a key instrument to encourage developing countries' participation in the mitigation of global climate change. Reduction of greenhouse gas (GHG) emissions through the energy supply and demand side activities are the main options to be implemented under the CDM. This paper analyses the general equilibrium effects of a supply side GHG mitigation option-the substitution of thermal power with hydropower--in Thailand under the CDM. A static multi-sector general equilibrium model has been developed for the purpose of this study. The key finding of the study is that the substitution of electricity generation from thermal power plants with that from hydropower plants would increase economic welfare in Thailand. The supply side option would, however, adversely affect the gross domestic product (GDP) and the trade balance. The percentage changes in economic welfare, GDP and trade balance increase with the level of substitution and the price of certified emission reduction (CER) units.     

取代苯甲酸类在水中固液平衡的研究

采用合成法测定了对氨基苯甲酸、邻氨基苯甲酸、邻氯基苯甲酸和间硝基苯甲酸在水中的固液平衡,分别用经验方程、Wilson方程、λH方程对实验数据进行拟合处理.Wilson方程和λH方程模型均能很好地关联四种取代苯甲酸类的水溶解度.