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101.
结合法律法规和专家咨询法,对整合产业进行生态影响识别,并与现有政策进行衔接,建立了青岛市三类省级生态红线区产业准入负面清单。土壤保持、水源涵养、生物多样性维护三类红线区涉及(A-T)20类产业,三类红线区B、C、H、K类是全禁止,生物多样性维护红线区F类全禁止。A类产业中仅有林业均是正影响,I类和M类产业生态影响小,L、Q、S类禁止所有设施建设。此外,一些产业受限于设施建设,如果仅提供服务,则不纳入负面清单。  相似文献   
102.
103.
采用超声辅助沉淀法—浸渍法制备了WO3/Ag3VO4复合光催化剂,对其进行了表征,考察了其在可见光条件下对罗丹明B的催化降解性能,并对催化机理进行了探讨。表征结果显示:WO3紧密包覆在Ag3VO4颗粒的表面,并未改变Ag3VO4的晶体结构;与Ag3VO4和WO3相比,WO3/Ag3VO4的吸收带边发生了红移。实验结果表明:w(WO3)为3.5%时,WO3/Ag3VO4对罗丹明B的可见光催化降解效果最好;在光催化剂加入量0.8 g/L、初始罗丹明B质量浓度10 mg/L的条件下,于室温下光照180 min时的罗丹明B去除率达95.76%,TOC去除率达96.5%;WO3与Ag3VO4在能带间的耦合作用下形成异质结结构,很好地抑制了光生电子-空穴对的复合。  相似文献   
104.
Synthesis of tributyl citrate (TBC) has been studied by using acid functionalized ionic liquid as catalyst. The results indicated that acidic ionic liquids show good catalytic and reusable performance. Under the optimum conditions, using 1-methyl-3-(3-sulfopropyl)-imidazolium hydrogen sulfate as catalyst, the conversion of citric acid was 97%. After easily separated from the products the ionic liquid could be reused 13 times without any disposal, and the conversion of citric acid was not less than 93%. Therefore, an environmental friendly approach for the synthesis of tributyl citrate is provided.  相似文献   
105.
An interactive dual-circulating fluidized bed system has been proposed in which the pyrolysis of sewage sludge(SS) and incineration of biomass proceed simultaneously, and alumina is used as the bed material and heat carrier. The alumina coated with biomass ash would mix with sewage sludge in the pyrolysis reactor of this device. It is important to know the influence of composite alumina(CA) on the pyrolysis progress. Sewage sludge was pyrolyzed in a fixed bed reactor from 400 to 600°C using CA as catalyst. The effects of temperature and CA additive ratio on the products were investigated. The product yields and component distribution of non-condensable gas were more sensitive to the change of temperature, and the maximum liquid yield of 48.44 wt.% and maximum Useable Energy of Liquid of 3871 k J/kg sludge were observed at 500°C with 1/5 CA/SS(mass ratio). The gas chromatography–mass spectrometry results showed that the increase of temperature enhanced devolatilization of organic matter and promoted cyclization and aromatization of aliphatics. The presence of CA could strengthen secondary cracking and interaction among primary products from different organic compounds, such as acid–amine condensation,and reduce the content of oxygenated compounds. When the CA additive amount exceeded a certain proportion, the aromatization was clearly strengthened. The effects of CA on decomposition of fatty acids and formation of aromatics were similar to that of temperature. This means that the reaction temperature could be lowered by introducing CA, which has a positive effect on reducing energy consumption.  相似文献   
106.
马铃薯加工项目产生的废水主要是高浓度有机废水,本文研究了通过采用气浮分离/UASB/SBR处理工艺处理此废水。经处理后,各污染物指标达到《淀粉工业水污染物排放标准》(GB 25461-2010)表2间接排放限值后排放城市污水处理厂。  相似文献   
107.
Excess phosphorus from non-point pollution sources is one of the key factors causing eutrophication in many lakes in China,so finding a cost-effective method to remove phosphorus from non-point pollution sources is very important for the health of the aqueous environment. Graphene was selected to support nanoscale zero-valent iron(nZVI)for phosphorus removal from synthetic rainwater runoff in this article. Compared with nZVI supported on other porous materials,graphene-supported nZVI(G-nZVI) could remove phosphorus more efficiently. The amount of nZVI in G-nZVI was an important factor in the removal of phosphorus by G-nZVI,and G-nZVI with 20 wt.% nZVI(20% G-nZVI)could remove phosphorus most efficiently. The nZVI was very stable and could disperse very well on graphene,as characterized by transmission electron microscopy(TEM) and scanning electron microscopy(SEM). X-ray photoelectron spectroscopy(XPS),Fourier Transform infrared spectroscopy(FT-IR) and Raman spectroscopy were used to elucidate the reaction process,and the results indicated that Fe-O-P was formed after phosphorus was adsorbed by G-nZVI. The results obtained from X-ray diffraction(XRD) indicated that the reaction product between nZVI supported on graphene and phosphorus was Fe3(PO4)2·8H2O(Vivianite). It was confirmed that the specific reaction mechanism for the removal of phosphorus with nZVI or G-nZVI was mainly due to chemical reaction between nZVI and phosphorus.  相似文献   
108.
上海市地面沉降的经济损失评估   总被引:11,自引:1,他引:11  
地面沉降是普遍的城市灾害和典型的缓慢积累型地质灾害。本文首次采用工程费用法,结合修正的人力资本法,定量评估了上海市由于地面沉降而修筑黄埔江、苏州河沿岸防汛墙的经济损失,估算了地面沉降造成码头、港口受淹、市区积水、桥梁净空减少等方面的经济损失。得出上海地面沉降的经济损失总额达508470.379万元,自1921年地面沉降以来每年的经济损失为7263.626万元。研究表明,控制地面沉降不仅具有积极的环境效益,更具有显著的经济效益。  相似文献   
109.
Environmental Science and Pollution Research - The photochemical role of Fe(III)-citrate complex is significant in natural waters due to its ubiquitous existence and excellent photoreactivity at...  相似文献   
110.
• Orange tree residuals biochar had a better ability to adsorb ammonia. • Modified tea tree residuals biochar had a stronger ability to remove phosphorus. • Partially-modified biochar could remove ammonia and phosphorus at the same time. • The real runoff experiment showed an ammonia nitrogen removal rate of about 80%. • The removal rate of total phosphorus in real runoff experiment was about 95%. Adsorption of biochars (BC) produced from cash crop residuals is an economical and practical technology for removing nutrients from agricultural runoff. In this study, BC made of orange tree trunks and tea tree twigs from the Laoguanhe Basin were produced and modified by aluminum chloride (Al-modified) and ferric sulfate solutions (Fe-modified) under various pyrolysis temperatures (200°C–600°C) and residence times (2–5 h). All produced and modified BC were further analyzed for their abilities to adsorb ammonia and phosphorus with initial concentrations of 10–40 mg/L and 4–12 mg/L, respectively. Fe-modified Tea Tree BC 2h/400°C showed the highest phosphorus adsorption capacity of 0.56 mg/g. Al-modified Orange Tree BC 3h/500°C showed the best performance for ammonia removal with an adsorption capacity of 1.72 mg/g. FTIR characterization showed that P = O bonds were formed after the adsorption of phosphorus by modified BC, N-H bonds were formed after ammonia adsorption. XPS analysis revealed that the key process of ammonia adsorption was the ion exchange between K+ and NH4+. Phosphorus adsorption was related to oxidation and interaction between PO43– and Fe3+. According to XRD results, ammonia was found in the form of potassium amide, while phosphorus was found in the form of iron hydrogen phosphates. The sorption isotherms showed that the Freundlich equation fits better for phosphorus adsorption, while the Langmuir equation fits better for ammonia adsorption. The simulated runoff infiltration experiment showed that 97.3% of ammonia was removed by Al-modified Orange tree BC 3h/500°C, and 92.9% of phosphorus was removed by Fe-modified Tea tree BC 2h/400°C.  相似文献   
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