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1.
Five biochars derived from lotus seedpod(LSP) were applied to examine and compare the adsorption capacity of 17β-estradiol(E2) from aqueous solution.The effect of KOH activation and the order of activation steps on material properties were discussed.The effect of contact time,initial concentration,p H,ionic strength and humic acid on E2 adsorption were investigated in a batch adsorption process.Experimental results demonstrated that the pseudo second-order model fitted the experimental data best and that adsorption equilibrium was reached within 20 hr.The efficiency of E2 removal increased with increasing E2 concentration and decreased with the increase of ionic strength.E2 adsorption on LSP-derived biochar(BCs) was influenced little by humic acid,and slightly affected by the solution p H when its value ranged from 4.0 to 9.0,but considerably affected at p H 10.0.Low environmental temperature is favorable for E2 adsorption.Chemisorption,π–π interactions,monolayer adsorption and electrostatic interaction are the possible adsorption mechanisms.Comparative studies indicated that KOH activation and the order of activation steps had significant impacts on the material.Post-treated biochar exhibited better adsorption capacity for E2 than direct treated,pretreated,and raw LSP biochar.Pyrolyzed biochar at higher temperature improved E2 removal.The excellent performance of BCs in removing E2 suggested that BCs have potential in E2 treatment and that the biochar directly treated by KOH would be a good choice for the treatment of E2 in aqueous solution,with its advantages of good efficiency and simple technology.  相似文献   
2.
为了均衡环保和经济增长间的关系,对环保压力下的经济增长方式进行改革。分析了资源与经济增长的关系、经济增长方式的内涵和经济增长方式的类型,介绍了国内外相关文献综述。对传统粗放型经济增长方式进行分析,发现其具有高投入、高消耗、低效益的特性,且中国单位产值所需的生产要素较其他发达国家和部分发展中国家高,但生产率与资金、资源利用率却比其他发达国家低。在面临环保压力时,中国因传统粗放型经济增长方式造成资源利用效率降低,影响经济增长,需对经济增长方式做出以下改革:转变生产函数,增加要素生产率,改变要素间相对地位;扩展价值链,使产业升级,提高附加值;改善产业结构,发展服务业。  相似文献   
3.
Catalytic wet air oxidation (CWAO) is one of the most promising technologies for pollution abatement. Developing catalysts with high activity and stability is crucial for the application of the CWAO process. The Mn/Ce complex oxide catalysts for CWAO of high concentration phenol-containing wastewater were prepared by coprecipitation. The catalyst preparation conditions were optimized by using an orthogonal layout method and single-factor experimental analysis. The Mn/Ce serial catalysts were characterized by Brunauer-Emmett-Teller (BET) analysis and the metal cation leaching was measured by inductively coupled plasma torch-atomic emission spectrometry (ICP-AES). The results show that the catalysts have high catalytic activities even at a low temperature (80°C) and low oxygen partial pressure (0.5 MPa) in a batch reactor. The metallic ion leaching is comparatively low (Mn<6.577 mg/L and Ce<0.6910 mg/L, respectively) in the CWAO process. The phenol, CODCr, and TOC removal efficiencies in the solution exceed 98.5% using the optimal catalyst (named CSP). The new catalyst would have a promising application in CWAO treatment of high concentration organic wastewater. Translated from Techniques and Equipment for Environmental Pollution Control, 2005, 6(2): 40–44 [译自: 环境污染治理技术与设备]  相似文献   
4.
催化快速法测定CODCr是我国目前环境监测中普遍使用的最快速、简便、可靠的方法 ,该法的检测范围是 60~ 1 0 0 0mg/l,我们经过研究测出催化快速法的定量下限为 1 0mg/l,扩大了该法的应用范围。  相似文献   
5.
本文报道了我国四大家鱼——青、草、鲢、鳙的乳酸脱氢酶(LDH)同功酶电泳图谱及毒物对草鱼血清乳酸脱氢酶(SLDH)同功酶谱的影响。 用聚丙烯酰胺垂直平板电泳,可以测出鲢、鳙血清中各有一条深色的LDH带、背、草鱼血清中含有五条深色的LDH同功酶带。草鱼不同器官组织匀浆中的LDH同功酶相对活性比例不同,与人类相似。 0.1ppm氯化汞、氯化镉、硝酸铅、硫酸铜,0.008ppm滴滴涕和0.84ppm对硫磷分别使草鱼致毒33天,发现氯化镉、硝酸铅使SLDH_5活性升高,氯化汞使SLDH_1升高,而硫酸铜使SLDH_4降低。在这个浓度下,滴滴涕、对硫磷致毒没有使鱼SLDH同功酶在比例上发生显著变化。 农药厂废水污染的Y湖中,肯、草、鲢、鳙SLDH总活性比污染较轻的T湖同种鱼高,特别是青、草鱼的SLDH_5活性明显升高。  相似文献   
6.
非线性灰色模型在污染物总量预测中的应用   总被引:6,自引:0,他引:6  
在前人工作的基础之上介绍了几种修正的GM(1,1)非线性模型,并以衡阳市1990~1996年城区污染物总量(COD)的预测为例,探讨了各种模型的应用效果。结果表明:非线性模型的拟合精度更高,具有更加广阔的发展前景。  相似文献   
7.
燃煤锅炉除尘脱硫废水处理与循环利用技术   总被引:2,自引:0,他引:2  
介绍了采用沉灰、沉渣中和、微滤三池毗连的废水处理方法及板式微孔过滤新技术,实现燃煤锅炉除尘脱硫废水封闭循环利用。  相似文献   
8.
确定不同保证率下的中国酸沉降临界负荷   总被引:6,自引:0,他引:6  
Duan L  Hao J  Zhou Z  Xie S 《环境科学》2002,23(5):25-28
在进行中国酸沉降临界负荷区划时 ,通常以 1°× 1°(经纬度 )的网格为单位进行计算 ,难以反映网格内不同生态系统对酸沉降敏感性的差异 .为了便于决策者根据临界负荷确定酸沉降控制对策 ,也为了使 1°× 1°的结果更具代表性和实用性 ,本研究确定了 0 1°× 0 1°网格为单位计算的中国酸沉降临界负荷 ,并在此基础上通过引入保证率的概念 ,得到了一系列与一定的经济技术水平相适应的、允许有一定损失的 1°× 1°的中国酸沉降临界负荷图 .利用累积分布函数 ,本研究还确定了不同保证率下的中国酸沉降超临界负荷分布和各省、市、自治区的酸沉降临界负荷 .  相似文献   
9.
降低油品储运损耗 改善大气环境   总被引:4,自引:0,他引:4  
从石油开采到成品油进入清费的过程中,损耗量约占原油量的3%-5%,其中储运过程中的损耗占总耗的40%-50%,着重论述了油品储运过程中降低损耗的措施,以减少经济损失和对环境的破坏。  相似文献   
10.
Numerous studies support that biodiversity predict most to ecosystem functioning, but whether other factors display a more significant direct impact on ecosystem functioning than biodiversity remains to be studied. We investigated 398 samples of the phytoplankton phosphorus resource use efficiency (RUEP = chlorophyll-a concentration/dissolved phosphate) across two seasons in nine plateau lakes in Yunnan Province, China. We identified the main contributors to phytoplankton RUEP and analyzed their potential influences on RUEP at different lake trophic states. The results showed that total nitrogen (TN) contributed the most to RUEP among the nine lakes, whereas community turnover (measured as community dissimilarity) explained the most to RUEP variation across the two seasons. Moreover, TN also influenced RUEP by affecting biodiversity. Species richness (SR), functional attribute diversity (FAD2), and dendrogram-based functional diversity (FDc) were positively correlated with RUEP in both seasons, while evenness was negatively correlated with RUEP at the end of the rainy season. We also found that the effects of biodiversity and turnover on RUEP depended on the lake trophic states. SR and FAD2 were positively correlated with RUEP in all three trophic states. Evenness showed a negative correlation with RUEP at the eutrophic and oligotrophic levels, but a positive correlation at the mesotrophic level. Turnover had a negative influence on RUEP at the eutrophic level, but a positive influence at the mesotrophic and oligotrophic levels. Overall, our results suggested that multiple factors and nutrient states need to be considered when the ecosystem functioning predictors and the biodiversity-ecosystem functioning relationships are investigated.  相似文献   
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