含砷污泥的粉煤灰固化研究

硫酸废水处理系统的中和污泥属于有害废渣,其中As浸出率超标.采用固化的方法处理某冶炼厂硫酸废水中和污泥,发现以水泥∶粉煤灰∶污泥=1∶1∶2的配比固化后,固化块浸出液浓度达到国标规定(1.5 mg/L).研究表明,粉煤灰替代水泥50%可达到较好的固化效果,浸泡24 d后浸出浓度达到稳定值,pH值为7时浸出浓度最小,外加剂对固化有负影响,采用湿养护可获得更好的效果.     

氧化沟反应器流体力学特性的数值模拟与实验研究

采用CFD数值计算和体视PIV测试相结合的方法研究卡鲁塞尔氧化沟反应器流场特性。探索复杂边界条件下反应器流场的模拟方法,采用体视PIV技术分别测量了反应器直道、弯道处三维全场流速;研究不同位置处纵、横、垂三向的流动结构和沿程分布特点。结果表明,模拟与实验结果较吻合;纵、垂两向的流动分布是决定沟内水力特性的主要因素;横、垂两向的流动是决定污泥沉积位置的主要因数;外沟靠近曝气叶轮直道段的流速分布上大下小,在低速区底部易发生污泥沉积;外沟远离曝气叶轮直道段流速分布上小下大,利于防止泥水分离;弯道段受横比降和横向环流的影响,内侧容易形成低速区或停滞区而发生污泥沉积。     

味精废水的清洁生产治理技术

介绍了味精废水清洁生产的工艺技术,并与传统的物化-生化方法进行了比较。运行结果表明:该工艺既节约能源,又经济可靠。     

海洋灾害影响下的社会综合稳定性结构

海洋灾害突发导致的经济波动、社会混乱和灾民心理的恐慌,给我国的经济发展和社会稳定带来了巨大的冲击.为了全方位把握海洋灾害期间的综合稳定性,必须从经济、社会和心理的角度进行全面的思考.在全面考虑稳定性的影响因素基础上,构建海洋灾害期间的稳定环境,保证海洋灾害期间的稳定性.     

正压空气呼吸器呼气阀弹簧设计

通过对开启压力与呼气阀及正压空气呼吸器相关指标之间关系的分析,提出将开启压力作为呼气阀设计参数可实现呼气阀的定量设计,并在此基础上对正压空气呼吸器呼气阀弹簧进行了定量设计和验证,同时对影响呼气阀弹簧设计的相关因素进行了详细探讨.     

内分泌干扰物对机体脂质代谢的影响及其机制研究进展

近年来许多动物实验研究表明,内分泌干扰物(endocrine disrupting chemicals,EDCs)暴露除了会损伤生殖、免疫和神经系统等,还能够干扰脂质代谢,增加肥胖、非酒精性脂肪肝和高脂血症等疾病的发病风险.笔者总结了多种EDCs对不同动物模型(哺乳动物、硬骨鱼类、两栖动物)脂质代谢的影响,主要包括促进...     

自然保护区的建立与持续发展的关系

自然保护区的建立已被世界公认是一种保护自然资源最有效的方法之一。但是长期以来,人们把对维持生物种类的持续发展以及生态系统的完整性都归功于较为传统的封闭式保护。事实证明这已导致保护与持续发展长期处于矛盾状态而得不到解决。自从联合国教科文组织人与生物圈计划提出“生物圈保护区”的概念以来,打破了长期以来对自然保护区的封闭式管理。强调通过保护自然资源而发展和利用资源,并使这些资源能够持续发展。注重把自然保护与科学研究,环境监测、示范、环境教育与当地人民的参与结合起来。     

Irrigation Water Allocation Using an Inexact Two‐Stage Quadratic Programming with Fuzzy Input under Climate Change

Agricultural irrigation accounts for nearly 70% of the total water use around the world. Uncertainties and climate change together exacerbate the complexity of optimal allocation of water resources for irrigation. An interval‐fuzzy two‐stage stochastic quadratic programming model is developed for determining the plans for water allocation for irrigation with maximum benefits. The model is shown to be applicable when inputs are expressed as discrete, fuzzy or random. In order to reflect the effect of marginal utility on benefit and cost, the model can also deal with nonlinearities in the objective function. Results from applying the model to a case study in the middle reaches of the Heihe River basin, China, show schemes for water allocation for irrigation of different crops in every month of the crop growth period under various flow levels are effective for achieving high economic benefits. Different climate change scenarios are used to analyze the impact of changing water requirement and water availability on irrigation water allocation. The proposed model can aid the decision maker in formulating desired irrigation water management policies in the wake of uncertainties and changing environment.     

Water Management Decision Making in the Face of Multiple Forms of Uncertainty and Risk

In the Wasatch Range Metropolitan Area of Northern Utah, water management decision makers confront multiple forms of uncertainty and risk. Adapting to these uncertainties and risks is critical for maintaining the long‐term sustainability of the region's water supply. This study draws on interview data to assess the major challenges climatic and social changes pose to Utah's water future, as well as potential solutions. The study identifies the water management adaptation decision‐making space shaped by the interacting institutional, social, economic, political, and biophysical processes that enable and constrain sustainable water management. The study finds water managers and other water actors see challenges related to reallocating water, including equitable water transfers and stakeholder cooperation, addressing population growth, and locating additional water supplies, as more problematic than the challenges posed by climate change. Furthermore, there is significant disagreement between water actors over how to best adapt to both climatic and social changes. This study concludes with a discussion of the path dependencies that present challenges to adaptive water management decision making, as well as opportunities for the pursuit of a new water management paradigm based on soft‐path solutions. Such knowledge is useful for understanding the institutional and social adaptations needed for water management to successfully address future uncertainties and risks.     

A study on oxidative degradation of polyacrylamide in wastewater with UV/FENTON/C4H4O62−

The degradation of polyacrylamide (PAM) in simulate wastewater was studied in UV/Fenton/C₄H₄O₆^2? system. The factors such as molecular ratio of H₂O₂/Fe²⁺/C₄H₄O₆^2?, pH, and the dosage of Fenton reagent that could affect the PAM degradation in the UV/Fenton/C₄H₄O₆^2? system were investigated. The experimental results showed that adding C₄H₄O₆^2? to UV/Fenton system could form photosensitive ferrous complexes, which led to higher degradation efficiency of PAM. The degradation rate of PAM could be up to 95.2% under the following conditions: the concentration of H₂O₂, Fe²⁺, and C₄H₄O₆^2? were 22.5, 2.25, and 2.25 mmol/L, respectively (i.e., molecular ratio of H₂O₂/Fe²⁺/C₄H₄O₆^2? was 10:1:1), the pH value was 3.0.