纳米零价铁铜双金属体系对土壤中四氯双酚A的降解

纳米零价铁及其双金属材料因比表面积大、反应活性高,已被大量应用于地下水中卤代有机污染物、无机盐和重金属的处理,而将纳米零价铁铜双金属(Cu/n ZVI)应用于四氯双酚A(TCBPA)污染土壤的修复却鲜见报道.本文以Cu/nZVI为反应材料,探究了TCBPA起始浓度,Cu/n ZVI投加量、p H、温度等因素对土壤中TCBPA降解率的影响.批实验结果表明:反应温度为25℃,经过360 min的反应后,0.30 g的Cu/n ZVI对土壤中0.8 mg·g~(-1)TCBPA的降解率可达85%以上.Cu/n ZVI对土壤中TCBPA的降解率随TCBPA初始浓度的增加而降低,随Cu/n ZVI投加量的增加而升高,随土壤初始p H的增加而降低,Cu/n ZVI对TCBPA的降解在常温条件下即可有效的进行.Cu/nZVI对TCBPA的降解遵循准一级反应动力学模型.GC-MS结果表明,Cu/n ZVI降解TCBPA是一个逐步还原脱氯的过程.     

THE USE OF MULTIPLE REGRESSION MODELS IN PREDICTING SEDIMENT YIELD1

ABSTRACT. Four commonly used models for predicting sediment yield are analyzed and compared using previously published data. Three of these models involve logarithmic transformations. Some of the problems involved in transforming data are discussed in the context of logarithmic transformations. These problems are illustrated using the results of standard regression analyses and economic loss function analyses. For the data analyzed, the linear model is preferable to each of the logarithmic models on the basis of each analysis, and the usual multiple objective nature of the model choice problem is thus modified. The extent to which these results can be generalized is discussed in the context of model choice.     

生态环境科技转化与产业发展融合之路探索

生态环境科技成果转化是深入贯彻落实党的十九大精神和国务院部署任务的抓手，是实现二氧化碳排放2030年达峰、2060年碳中和目标的重要举措，是落实绿色发展战略、实现我国可持续发展的关键之举。本文通过对我国生态环境科技成果转化现状进行分析，指出现阶段国内生态环境科技成果由于存在“不愿用”“不易用”“不实用”等问题导致转化率仅为10%左右。同时，在构建国内大循环为主体、国内国际双循环相互促进的新发展格局的要求下，文章结合以5G和物联网技术为代表的新科技浪潮发展趋势，提出以习近平总书记“四个面向”“三个导向”要求为原则指导生态环境科技成果转化，从促进生态环境科技与生态环境保护产业协调发展、强化产品生态友好设计、注重多学科交叉等多方面，推进生态环境科技转化更好地与产业发展相融合。     

我国焦化行业面临的环境困境及绿色转型策略

综述了我国焦化行业的产能、产量、布局、装备水平及污染物排放特征,剖析了我国焦化行业目前存在的产能过剩、废气污染源超标排放、兰炭企业管理薄弱、独立焦化企业大量存在以及大气环境防护距离难以满足要求等环境困境,从构建煤焦钢产业链、做好排放标准与排污许可制度的衔接、加强对焦化企业的科学监管、实施科学合理的停限产方案、强化VOCs治理工作等方面提出了行业绿色转型发展的对策建议。     

灰色摆动序列的GM（1,1）拟合建模法及其应用

建立了灰色摆动序列ＧＭ（１,１）动态指数变换拟合建模方法,对某地工业固体废物产生量的预测结果表明,该法合理有效,切实可行,并有良好的精度。     

Assessment of the state of vegetation and prognosis of its anthropogenic dynamics in specially protected nature areas on the basis of Phytoecological mapping

Methodological approaches to the construction of phytoecological maps are described regarding specially protected nature areas and their specific features. Such maps offer new possibilities for the assessment and analysis of current and predicted states of vegetation.     

Specific Features of the Formation of Animal Species Communities in Technogenic and Urbanized Landscapes

The formation of the species composition and specific functional, physiological, and phenotypic features of populations in technogenic and urbanized areas was studied by analyzing murine rodents, amphibians, and soil invertebrates. It is shown that, against the background of decreasing total abundance and biomass of animals, their formerly continuous ranges become mosaic, with the locally increasing animal density and heterogeneity and specific population dynamics. Species diversity decreases; however, species alien to the natural ecosystems of the given territory appear. Changes in the strategies of reproduction and food resource use were revealed in the species communities of small mammals and amphibians.     

离子掺杂效应对二氧化锆热稳定性的影响

本文利用X -射线衍射技术及比表面测试 ,研究了La3 、Ce4 、Ti4 掺杂离子对亚稳态t-ZrO2 晶相转变及对t-ZrO2 比表面积的影响。最后发现掺杂离子能有效的提高亚稳态t-ZrO2 的热稳定性能。其中La3 和Ce4 离子能有效的推迟亚稳态t-ZrO2 的晶相转变温度。并发现离子掺杂效应对二氧化锆热稳定性作用大小排列顺序为 :La3 >Ce4 >Ti4 。     

澎溪河消落带典型植物群落根际土壤无机氮形态及氮转化酶活性

三峡库区消落带是典型的生态脆弱带,其土壤N循环因受到植物根际效应和季节性淹水的影响而具有特殊性.本研究以三峡库区一级支流澎溪河消落带为例,选择4种植被(狗牙根、香附子、苍耳以及玉米)覆盖区,采集植物根际、非根际土壤,分析根际土壤与非根际土壤理化性质、无机氮形态以及7种N素转化相关酶,并比较了4种植物根际效应强度,以反映不同植物覆盖对消落带土壤N循环过程的影响.研究表明:供试植物根际土壤pH值均低于非根际,有机质、全氮、全磷含量均高于非根际,表明植物根际对消落带土壤养分有富集作用;4种植物根际土壤硝态氮、铵态氮、亚硝态氮及14d可矿化氮含量均高于非根际,且土壤硝态氮、亚硝态氮以及14d可矿化氮含量呈现香附子＞狗牙根＞苍耳/玉米;总体上根际土壤N转化酶活性高于非根际,且狗牙根和香附子覆盖区脲酶、亚硝酸还原酶、谷氨酰胺酶、脱氢酶显著高于玉米和苍耳覆盖区;蛋白酶、脲酶、谷氨酰胺酶活性与4种N形态均呈显著相关性,是消落带土壤N转化的主要参与酶类;根际效应分析结果香附子和狗牙根对消落带土壤N转化的根际效应强度大于苍耳和玉米,有利于土壤N素的固定和保持.植物根际效应对消落带土壤N素循环的影响可为消落带植被恢复工程中植被选择提供参考,也为改善消落带土壤退化相关研究提供科学支撑.     

Iron-carbon composite microspheres prepared through a facile aerosol-based process for the simultaneous adsorption and reduction of chlorinated hydrocarbons

Iron-carbon (Fe-C) composite microspheres prepared through a facile aerosol-based process are effective remediation agents for the simultaneous adsorption and reduction of chlorinated hydrocarbons. Complete dechlorination was achieved for the class of chlorinated ethenes that include tetrachloroethylene (PCE), trichloroethylene (TCE), cis- and trans-1,2-dicloroethylene (c-DCE, t-DCE), 1,1-dichloroethylene (1,1-DCE) and, vinyl chloride (VC). The Fe-C particles potentially provides multi-functionality with requisite characteristics of adsorption, reaction, and transport for the effective in situ remediation of chlorinated hydrocarbons. The carbon support immobilizes the ferromagnetic iron nanoparticles onto its surface, thereby inhibiting aggregation. The adsorptive nature of the carbon support prevents the release of toxic intermediates such as the dichloroethylenes and vinyl chloride. The adsorption of chlorinated ethenes on the Fe-C composites is higher (>80%) than that of humic acid (<35%) and comparable to adsorption on commercial activated carbons (>90%). The aerosol-based process is an efficient method to prepare adsorptive-reactive composite particles in the optimal size range for transport through the porous media and as effective targeted delivery agents for the in situ remediation of soil and groundwater contaminants.