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181.
Practical engineering approaches and infrastructure to address the problem of marine debris in Korea
Rho-Taek Jung Author Vitae Hong Gun Sung Sang-In Keel 《Marine pollution bulletin》2010,60(9):1523-1532
As a solution to the problem of persistent solid marine debris, a nationwide project began in Korea in 1999 to develop and popularize fundamental changes to the infrastructure. The ten year project, called “A Practical Integrated System for Marine Debris,” consists of four linked types of technology: prevention, deep-water survey, removal and treatment (recycling). These reflect the characteristics of marine debris, which though widespread, vary by location and time of generation. Each technical component has each representative outcome that has been outreached the local governments and marine debris-related associations. The in situ infrastructures lead to enhance the retrieval of the marine debris and create direct and indirect benefits to industry. Both end-of-pipe technology improvement and the introduction of front-of-pipe technology should be considered as we strive to reduce the generation of marine debris in Korean coastal areas. 相似文献
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183.
岩石—土壤—植被(红背山麻杆、裸花紫珠)间的元素迁移——以广西巴马岩溶石山地区为例 总被引:3,自引:2,他引:1
通过对碳酸盐岩与土壤、碳酸盐岩与红背山麻杆、裸花紫珠及土壤与红背山麻杆、裸花紫珠间的元素相关分析,发现:(1)碳酸盐岩和土壤的元素存在高度的相关关系,从岩石到土壤,元素迁移顺序总体表现为:CaO>MgO>Na2O>P2O5>MnO>Pb>Zr>Fe2O3>TiO2>SiO2>Al2O3;(2)土壤与两种检测植物的元素也存在较高的相关性,并且两种检测植物还表现出基本相似的土壤元素生物吸收系数,即:红背山麻杆的土壤元素生物吸收系数顺序为:P>Ca>Fe>K>Na>Mn>Pb>Al>Mg>Zr>Ti>SiO2,裸花紫珠的为:P>K>Fe>Na>Ca>Mn>Al>Pb>Mg>Zr>Ti>SiO2;(3)植物中的常量元素由岩石中的常量元素所决定,在同样的岩性基底上,不同植物体内富集、累积而成的元素结构有着较高的一致性。 相似文献
184.
Subramanyan Vasudevan Florence Epron Jothinathan Lakshmi Subbiah Ravichandran Swaminathan Mohan Ganapathy Sozhan 《洁净——土壤、空气、水》2010,38(3):225-229
The present study provides an electrocoagulation method, for the removal of NO3– from drinking water using magnesium as the anode and cathode. The experiments are carried out as a function of pH, temperature, and current density. The results show that the maximum removal efficiency of 95.8% was achieved at a current density of 0.25 A/dm2, at a pH of 7.0. The adsorption of NO3– preferably fitting the Langmuir adsorption isotherm suggests monolayer coverage of the adsorbed molecules. The adsorption process follows a second‐order kinetics model. Thermodynamic studies show that the adsorption was exothermic and spontaneous in nature. 相似文献
185.
186.
Juan-Luis Valera Ana-María Negredo Antonio Villaseñor 《Pure and Applied Geophysics》2008,165(8):1683-1706
Convective removal and mantle delamination are geodynamical mechanisms proposed to explain the presence of extension in the
Alboran Sea within a regional context of compression. Using a new thermo-mechanical algorithm, we present here a quantitative
evaluation and comparison of conceptual models based on these geodynamical mechanisms. In contrast to the in situ convective removal process, the laterally propagating delamination mechanism is shown here to be consistent with first-order
features of the Alboran Sea such as the thinning/thickening distribution, intermediate-depth seismicity and upper mantle structure
imaged by seismic tomography. The lower crust is predicted to reach depths of 100–150 km in some areas, due to mechanically-driven
viscous drag of the downwelling mantle. 相似文献
187.
188.
Simranjeet Singh Praveen C Ramamurthy Daljeet Singh Dhanjal Sikander Rana Deepika Bhatia Ramesh Kanwar Neeta Raj Sharma Joginder Singh 《洁净——土壤、空气、水》2023,51(3):2100396
Agricultural biomass is proven ecofriendly and effective adsorbent for the remediation of contaminants from wastewater. Here, rice husk biochar (600 °C) prepared by a one-step pyrolysis method is used for the remediation of different contaminants in real samples. An onsite biofilter unit is fabricated with parallel trenches of different layers of coconut coir and biochar and is used as a biofiltration unit. The efficiency of the designed unit is assessed for the removal of different contaminants in pilot-scale experiments. Results show that removal efficiency varies from metal to metal and ranges from 5.52% to 90.76% using the biofilter unit. Fourier-transform infrared spectroscopy, scanning electron microscopy with energy dispersive X-ray analysis, carbon, hydrogen, nitrogen, and Brunauer–Emmett–Teller analysis before and after the adsorption represent the changes in the morphology and surface functionalization of the biochar. Results indicate that the designed biofilter unit could also be used as a promising agent for the remediation of pharmaceutical and other emerging contaminants from wastewater. 相似文献
189.
Alper Erdem Yılmaz Yeşim Dede Sağsöz Baybars Ali Fil Murat Tolga Yılmaz 《洁净——土壤、空气、水》2023,51(1):2200032
In this study, domestic wastewater was used as the electrolyte. The work was carried out with an up-flow tubular reactor, made of stainless steel that was used as cathode, while the anode electrode material was aluminum and varying values of flow regime (25, 50, 75 and 100 mL/s for continuous system), initial pH value (5, 6, 7 and 7.8) and current intensity (10, 15 and 20 A) were applied. For domestic wastewater with natural pH, the effluent pH was >9 in the batch system, while in the continuous system the pH was 8–8.5. Likewise, while the effluent temperature was up to 60°C in the batch system, it was at most 35°C in the continuous system. However, the energy consumption values in the continuous system were considerably lower compared with the batch system. At a current intensity of 10 A, 80 kWh of energy per unit volume was consumed in the batch system, while it was 50 kWh for the continuous system. The present results show that the batch system can be used for small wastewater streams whereas the continuous system can be used for large wastewater streams for domestic wastewater treatment. 相似文献
190.
消除层间多次波是地震勘探资料处理研究领域的难题,尤其对于实际资料的处理,到目前为止还很难找到一种完全有效的方法. 本文给出了仅对一次波成像既波路径偏移方法压制层间多次波方法,在共炮道集和共检波点道集分别计算炮点射线的入射角和检波点射线的出射角,由此计算的角度作为射线追踪的初始角度,计算地震波射线的传播路径. 结合由程函方程计算的走时表,判断偏移范围是反射波还是多次波. 在前期偏移过程压制多次波的理论研究基础上,本文主要研究波路径偏移消除多次波的应用部分. 为了进一步说明效果的有效性,计算了在单炮和共成像点道集压制层间多次波,给出了实际资料的压制多次波的偏移结果. 相似文献