Mechanism and catalytic performance for direct dimethyl ether synthesis by CO2 hydrogenation over CuZnZr/ferrierite hybrid catalyst

Direct synthesis of dimethyl ether(DME) by CO₂ hydrogenation has been investigated over three hybrid catalysts prepared by different methods:co-precipitation,sol-gel,and solid grinding to produce mixed Cu,ZnO,ZrO₂ catalysts that were physically mixed with a commercial ferrierite(FER) zeolite.The catalysts were characterized by N₂ physisorption,X-ray diffraction(XRD),transmission electron microscopy(TEM),X-ray photoelectron spectroscopy(XPS),temperature programmed...     

臭氧化法水处理技术

对臭氧化法水处理中不同技术问题分类进行了探讨。通过对臭氧的生成技术,臭氧的产生机理及在水中的氧化机理,供臭氧发生器使用的中频脉冲电源的阐述,证明了臭氧化法在水处理中的可行性和实用性。     

Ozone episodes during and after the 2018 Chinese National Day holidays in Guangzhou: Implications for the control of precursor VOCs

The impact of reducing industrial emissions of volatile organic compounds (VOCs) on ozone (O₃) pollution is of wide concern particularly in highly industrialized megacities. In this study, O₃, nitrogen oxides (NOx) and VOCs were measured at an urban site in the Pearl River Delta region during the 2018 Chinese National Day Holidays and two after-holiday periods (one with ozone pollution and another without). O₃ pollution occurred throughout the 7-day holidays even industrial emissions of VOCs were passively reduced due to temporary factory shutdowns, and the toluene to benzene ratios dropped from ∼10 during non-holidays to ∼5 during the holidays. Box model (AtChem2-MCM) simulations with the input of observation data revealed that O₃ formation was all VOC-limited, and alkenes had the highest relative incremental reactivity (RIR) during the holiday and non-holiday O₃ episodes while aromatics had the highest RIR during the non-pollution period. Box model also demonstrated that even aromatics decreased proportionally to levels with near-zero contributions of industrial aromatic solvents, O₃ concentrations would only decrease by less than 20% during the holiday and non-holiday O₃ episodes and ozone pollution in the periods could not be eliminated. The results imply that controlling emissions of industrial aromatic solvents might be not enough to eliminate O₃ pollution in the region, and more attention should be paid to anthropogenic reactive alkenes. Isoprene and formaldehyde were among the top 3 species by RIRs in all the three pollution and non-pollution periods, suggesting substantial contribution to O₃ formation from biogenic VOCs.     

以生态足迹法分析评估抚顺市可持续发展

在介绍生态足迹理论和计算模型的基础上,对抚顺市2007年的可持续发展状态进行了实例计算和分析,结果表明抚顺2007年的生态赤字为4.986 3hm2,其城市处于非可持续发展的状态.在此基础上,提出了促进抚顺可持续发展的建议.     

Investigation on mechanism of phosphate removal on carbonized sludge adsorbent

For the removal of phosphate (PO₄^3 -) from water, an adsorbent was prepared via carbonization of sewage sludge from a wastewater treatment plant: carbonized sludge adsorbent (CSA). The mechanism of phosphate removal was determined after studying the structure and chemical properties of the CSA and its influence on phosphate removal. The results demonstrate that phosphate adsorption by the CSA can be fitted with the pseudo second-order kinetics and Langmuir isotherm models, indicating that the adsorption is single molecular layer adsorption dominated by chemical reaction. The active sites binding phosphate on the surface are composed of mineral particles containing Si/Ca/Al/Fe. The mineral containing Ca, calcite, is the main factor responsible for phosphate removal. The phosphate removal mechanism is a complex process including crystallization via the interaction between Ca^2 + and PO₄^3 -; formation of precipitates of Ca^2 +, Al^3 +, and PO₄^3 -; and adsorption of PO₄^3 - on some recalcitrant oxides composed of Si/Al/Fe.     

基于生态足迹我国三大经济圈可持续发展能力研究

本文基于当前国际上流行的生态足迹(Ecological Footprint,简称EF)模型,以可持续发展理论、区域经济学理论、生态经济理论等相关理论为基础,理论分析与实证分析、定性分析与定量分析相结合的原则,采用社会经济各相关部门的统计数据、相关研究报告的资料,针对中国东部地区三大经济圈的实际情况,建立了区域可持续发展评价指标,评价了三大经济圈的可持续发展能力,明确了当前三大经济圈社会经济发展所处的状态、存在的问题,研究结果可以为制定保证三大经济圈社会、经济实现可持续发展的政策提供科学依据和指导.研究表明,我国三大经济圈可持续发展能力较差,内部的经济与环境不协调性以及不合理的经济结构是制约三大经济圈可持续发展的主要问题.     

跨流域环境污染联合处置机制初探——以苏鲁边界环保联席治污为例

随着经济的发展,流域水环境污染已成为制约区域经济和社会发展的关键性因素,流域跨界污染对上下游城市的水资源配置、社会稳定、经济可持续性等都提出严峻挑战。苏鲁边界九县（市）创造性地开展区域环境保护联席会议联防联治机制,为解决跨流域污染问题探索出了一条新路。     

e-Serem – A Web-Based Manual For The Estimation of Emission Reductions From JI and CDM Projects

This paper presentse-SEREM (Smart Emission ReductionEstimation Manual), a cost-free, easilyaccessed and updated, web-based manual forestimating emission reductions from Joint Implementation (JI) andClean Development Mechanism (CDM) projects. e-SEREM's main functions arethe selection of a benchmark for a specificproject type in the power or heat sectorand the calculation of the annual andcumulative emission reductions accrued bythis project for its crediting lifetime.e-SEREM was developed in order to test itsapplicability and practicality in assistingproject developers and evaluators toelaborate baselines easily and calculatethe emission credits earned by candidate JIor CDM projects hosted in several countries.     

威海市生态环境特色及其发展策略

论述了影响威海市生态环境建设的因素 ,在充分分析这些因素的优势及劣势基础上 ,对威海生态环境及可持续发展城市建设提出了一系列实施策略 ,为威海市地区生态环境发展方向的调节提供参考依据