| 1. |
- Danish, M., et al.
(författare)
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The Effect of Chelating Agents on Enhancement of 1,1,1-Trichloroethane and Trichloroethylene Degradation by Z-nZVI-Catalyzed Percarbonate Process
- 2016
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Ingår i: Water, Air and Soil Pollution. - : Springer Science and Business Media LLC. - 0049-6979 .- 1573-2932. ; 227:9
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Tidskriftsartikel (refereegranskat)abstract
- This study primarily focused on the performance of 1,1,1-trichloroethane (1,1,1-TCA) and trichloroethylene (TCE) degradation involving redox reactions in zeolite-supported nanozerovalent iron composite (Z-nZVI)-catalyzed sodium percarbonate (SPC) system in aqueous solution with five different chelating agents (CAs) including oxalic acid (OA), citric acid monohydrate (CAM), glutamic acid (GA), ethylenediaminetetraacetic acid (EDTA), and L-ascorbic acid (ASC). The experimental results showed that the addition of OA achieved almost 100 % degradation of 1,1,1-TCA and TCE. The addition of CAM and GA also significantly increased the contaminant degradation, while excessive addition of them inhibited the degradation. In contrast, EDTA and ASC showed negative impacts on 1,1,1-TCA and TCE degradation, which might be due to the strong reactivity with iron and OH● scavenging characteristics. The efficiency with CA addition on 1,1,1-TCA and TCE degradation decreased in the order of OA > CAM > GA > no CAs > EDTA > ASC. The extensive investigations using probe compound tests and scavenger tests revealed that both contaminants degraded primarily by OH● and O2 –● in chelated Z-nZVI-catalyzed SPC system. The significant improvement in 1,1,1-TCA and TCE degradation efficiency was accredited due to the (i) increase in concentration of Fe2+ and (ii) continuous generation of OH● radicals and maintenance of its quantity, ensuring more stability in the aqueous solution. Finally, the complete mineralization of 1,1,1-TCA and TCE in the OA-chelated, Z-nZVI-catalyzed SPC system was confirmed without any chlorinated intermediate by-products detected, demonstrating a great potential of this technique in the application of groundwater remediation.
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| 2. |
- Wang, K., et al.
(författare)
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Amended soils with weathered coal exhibited greater resistance to aggregate breakdown than those with biochar : From the viewpoint of soil internal forces
- 2024
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Ingår i: Soil & Tillage Research. - : Elsevier B.V.. - 0167-1987 .- 1879-3444. ; 244
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Tidskriftsartikel (refereegranskat)abstract
- Soil erosion is the first threat to soil functions. Reducing the soil aggregate breakdown strength is a key step to improve the soil's ability to resist rainfall splash erosion. Soil internal forces have been found to be the initial and important forces driving aggregate turnover. The application of exogenous organic materials can effectively improve soil aggregate stability and the resistance to rainfall erosion of agricultural soils. However, from the perspective of soil internal forces, information about the reduction effects of the exogenous organic materials application on soil aggregate breakdown is scarce, especially in comparing the effects of different materials. In this study, weathered coal and biochar were individually applied to loamy clay soil at rates of 0 %, 1 %, 2 %, and 3 % (w/w). Soil internal forces, aggregate breakdown strength, and splash erosion rate of different amended soils were then examined after four years. The results showed that compared with unamended soils (0 %), both weathered coal and biochar applications clearly increased the van der Waals attractive pressure and thus decreased the positive net pressure between soil particles. Additionally, these materials reduced soil aggregate breakdown strength and splash erosion rate. The application effects of the two materials were increased with their application rates. Under a lower electrolyte concentration in soil solution (0.0001 mol L−1), the aggregate breakdown strength in the soils amended with weathered coal was lower than that with biochar by 9.6 %, 23.2 %, and 17.7 % (when the diameter of broken aggregate was < 10 μm) and by 10.3 %, 20.8 %, and 17.5 % (when the diameter of broken aggregate was < 20 μm) at the 1 %, 2 %, and 3 % application rates, respectively (P < 0.05). Additionally, soils amended with weathered coal exhibited lower splash erosion rates compared to those amended with biochar, particularly at the higher application rate of 3 %. From the viewpoint of soil internal forces, weathered coal appears to be a suitable exogenous organic material for improving soil aggregate stability and anti-erosion ability during rainfall events. Our findings provide valuable insights into utilizing exogenous materials to improve soil resistance to rainfall splash erosion, assisting agricultural soil management in areas frequently affected by rainfall erosion.
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| 3. |
- Zhang, X., et al.
(författare)
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Greater mineral and aggregate protection for organic carbon in the soil amended by weathered coal than by biochar : Based on a 3-year field experiment
- 2023
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Ingår i: Geoderma. - : Elsevier B.V.. - 0016-7061 .- 1872-6259. ; 438
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Tidskriftsartikel (refereegranskat)abstract
- Soil carbon pool stability plays an important role in reaching carbon neutrality and mitigating global warming. Applying soil amendments is a practical strategy in agricultural production to improve soil environment. Weathered coal (WC) is an organic amendment that can be used to improve soil quality. However, the effects of WC application on soil organic carbon pool stability, and its differences from the effects of biochar (BC, a common amendment) application remains unclear. In this study, BC was selected as a comparison to further evaluate the potential of WC based on a 3-year field experiment, in which WC and BC were individually applied into a loamy clay soil at 0%, 1%, and 3% (w/w) rates. Soil organic carbon and its fractions (including particulate organic carbon and mineral-bound organic carbon), soil aggregate fractions and its stability, and the organic carbon content in aggregates were examined. The results showed that both WC and BC significantly increased soil total organic carbon, particulate and mineral-bound organic carbon (P < 0.05). The mineral-bound organic carbon content in WC treatment was significantly higher than that in BC treatment (by 32% under the 3% rate) (P < 0.05), whereas, there were no significant differences in soil total organic carbon content. Both WC and BC increased the soil organic carbon content in all aggregate fractions. While only the WC improved the soil aggregate stability, and which was 15% (under 1% rate) and 28% (under 3% rate) higher in WC treatments than in BC treatments (P < 0.05). The proportion of mineral-bound organic carbon to soil total organic carbon content and the soil aggregate stability were obviously related the soil C/N, and the WC treatments had a higher proportion of mineral-bound organic carbon and soil aggregate stability than BC treatments under the same soil C/N. The results indicated that the application of WC may be more effective than BC in increasing mineral and aggregate protection for soil organic carbon and thus improving soil carbon pool stability. Additionally, the purchase cost of WC was clearly lower than that of BC. Combined with the low cost and the benefits in soil structure and carbon pool stability, the application of WC appeared to have advantages over BC. Our findings provide robust evidence that WC is more effective than BC in improving soil carbon pool stability.
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| 4. |
- Fan, Jingli, et al.
(författare)
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Unified efficiency measurement of coal-fired power plants in China considering group heterogeneity and technological gaps
- 2020
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Ingår i: Energy Economics. - : Elsevier B.V.. - 0140-9883 .- 1873-6181. ; 88
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Tidskriftsartikel (refereegranskat)abstract
- China's coal-fired power generation has accounted for a large proportion of the power supply for a long time and the resulting environmental pollution and waste of resources have hindered the sustainable development of the power industry. To solve this problem, this study combines the concept of natural and managerial disposability with the non-concave meta-frontier method to determine the unified efficiency measurement of 251 coal-fired power plants in China from 2012 to 2014 and to investigate the sources of inefficiency in different areas. The results show that although the unified efficiency of China's coal-fired power plants improved significantly during 2012–2014, much room for improvement remains in terms of power generation and environmental performance. Due to the advanced technology of coal-fired power plants, the eastern area has the highest unified efficiency in terms of natural and managerial disposability. The western region has the lowest operational performance and the northeast region has the lowest environmental performance. The decomposition of the sources of inefficiency indicates that the inefficiency of coal-fired power plants in eastern China is mainly caused by management factors, whereas the inefficiency in northeastern China is due to a lag in technology. In the central and western areas, technical inefficiency and management inefficiency both account for a considerable proportion in their sources of inefficiency. Therefore, these regions need to improve both the management (e.g., reasonable allocation of utilization hours) and technology (e.g., clean coal technology) aspects to improve the unified performance of coal-fired power plants.
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| 5. |
- Farooq, U., et al.
(författare)
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Efficient transformation in characteristics of cations supported-reduced graphene oxide nanocomposites for the destruction of trichloroethane
- 2017
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Ingår i: Applied Catalysis A. - : Elsevier B.V.. - 0926-860X .- 1873-3875. ; 544, s. 10-20
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Tidskriftsartikel (refereegranskat)abstract
- Experiments were conducted to investigate the use of graphene-oxide supported metallic nanocomposites for improving the degradation of trichloroethane (TCA) by sodium percarbonate (SPC). Two methods of production, chemical reduction (CR) and solvo-thermal (ST), were tested for preparation of single (Fe) and binary (Fe-Cu) nanocomposites supported by reduced graphene oxide (rGO). A variety of analytical techniques including N2 adsorption Brunauer-Emmett-Teller (BET), x-ray diffraction (XRD), fourier-transfrom infrared spectroscopy (FTIR), and transmisison electron microscopy (TEM) were applied to characterize the physicochemical and microstructural properties of the synthesized nanocomposites. The characterization indicated that the CR method produced nanocomposites that comprised only mesoporous structure. Conversely, both micro and mesoporous structures were present for samples produced with the ST method. The synthesized single and bimetallic composites produced from the ST method showed higher surface areas, i.e. 93.6 m2/g and 119.2 m2/g as compared to the ones synthesized via the CR method, i.e. 13.8 m2/g and 38.0 m2/g respectively. The results of FTIR and XRD analyses confirmed that the ST method produced highly crystalline nanocomposites. SEM and TEM analysis validated that metallic particles with definite morphology well distributed on the surface of rGO. X-ray photoelectron spectroscopy (XPS) analysis confirmed the homogeneity nanocomposites and occurrence of variation in copper oxidation states during degradation process. EDS mapping validate the homogeneous distribution of Cu and Fe at reduced graphene oxide surface. The Fe-Cu/rGO (ST) activated SPC system effectively degraded TCA (92%) in 2.5 h at low nanocomposite dose compared to the Fe-Cu/rGO (CR) and only Fe, for which the maximum degradation efficiencies achieved were 81% and 34%. In conclusion, excellent catalytic characteristics were observed for the ST-synthesized single and bimetallic (Fe/rGO, Fe-Cu/rGO) catalysts. These catalysts were successful in improving the degradation of TCA via activated SPC.
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| 6. |
- Jiang, X., et al.
(författare)
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Rural tourism network evaluation based on resource control ability analysis : A case study of Ning’an, China
- 2021
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Ingår i: Land. - : MDPI AG. - 2073-445X. ; 10:4
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Tidskriftsartikel (refereegranskat)abstract
- Organization of rural tourism resources is important for optimizing rural land use based on rational resource classification. Quantitative analysis was performed to evaluate the resource control ability of rural tourism networks. This was achieved by determining the resource control relationship and assessing the structure of the rural tourism network. The ability of resource control was analyzed via resource abstraction, which included the extraction of resource nodes and corridors, control scope analysis, and network structure level evaluation. The proposed approach was applied to the Ning’an in Heilongjiang Province, China, and proved to be effective for exploring the network degree and development trends in rural tourism resources. By examining the resource control ability, the spatial characteristics and development trend in rural tourism networks were quantitatively analyzed, especially the connection mode of key tourism resources, network structure analysis, and resource linking ability. The core resources showed a lack of outward ability in the network, and the secondary resource expansion ability was limited. Via resource control ability analysis, this study focused on areas with rich tourism but an unbalanced spatial structure, combining the directional characteristics of the network to provide suggestions for the optimization rural tourism resources network in other regions of the world.
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| 7. |
- Qiu, R., et al.
(författare)
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A model-experience-driven method for the planning of refined product primary logistics
- 2022
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Ingår i: Chemical Engineering Science. - : Elsevier Ltd. - 0009-2509 .- 1873-4405. ; 254
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Tidskriftsartikel (refereegranskat)abstract
- Logistics planning is regarded as the most complex part of supply chain management for refined products. A vital knowledge gap still exists in understanding the trade-offs between the economy and the practicability of logistics schemes. Focus on this issue, this paper proposes a model-experience-driven method for the planning of refined product primary logistics. The method couples three sub-modules: (1) use coordinator's preference information and convex function interpolation to construct satisfaction indicator; (2) set up a multi-objective model for logistics coordination and optimization considering supply adjustment and secondary delivery; (3) adopt the augmented ɛ-constraint method to obtain the Pareto solutions and balance the economy and satisfaction indicators. The method is verified by a small-scale system, where the satisfaction degree increases by 77% while the logistics cost remains unchanged. The method is also successfully applied to a large-scale system with 29 refineries and 196 market depots, where Pareto logistics schemes are obtained and the supply–demand imbalance is greatly eased. The proposed method can help provide theoretical guidance for real-world logistics planning.
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| 8. |
- Wei, X., et al.
(författare)
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Assessing benefits in the flexibility of refined oil logistics from pipeline network integration reform : A case from South China
- 2022
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Ingår i: Chemical Engineering Science. - : Elsevier Ltd. - 0009-2509 .- 1873-4405. ; 253
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Tidskriftsartikel (refereegranskat)abstract
- The pipeline network integration reform enables unified management of pipelines from different entities. For refined oil logistics, this paper proposes a framework based on the MILP optimization model to quantify its flexibility. Considering the uncertainty, three disturbances occur in the logistics concurrently, and 10,000 simulations are performed to obtain the turnover cost. The ratio of pipeline transportation cost to the calculated average turnover cost is defined as the flexibility indicator. Taking China's largest refined oil pipeline network as an example, the results show that the flexibility rises 8.9% after the reform. The paper also quantifies the impact of the reform on logistics flexibility in South China, which is embodied in achieving lower freights and GHG emissions, lower impact by fluctuations, higher pipeline utilization, more efficient oil product turnover, and the avoiding of depot shortages when facing logistical disturbances. The underlying reasons for the results and 3E analysis are analyzed.
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| 9. |
- Wu, Y., et al.
(författare)
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A synchronization methodology for 3D offshore wind farm layout optimization with multi-type wind turbines and obstacle-avoiding cable network
- 2022
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Ingår i: Renewable energy. - : Elsevier Ltd. - 0960-1481 .- 1879-0682. ; 185, s. 302-320
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Tidskriftsartikel (refereegranskat)abstract
- Offshore wind farms are increasingly becoming the focus of clean sources market because of the huge energy potential and fast-maturing technology. The existing researches normally optimize the wind turbine layout and two-dimensional cable routing independently. This work focuses on the synchronization optimization of site selection of the offshore wind farm, three-dimensional wind turbine layout and three-dimensional cable network routing based on meta-heuristic algorithms and geographic information systems. Several practical issues, i.e., restricted areas, power generation, cable network and energy loss, are taken into consideration. A two-layer model is proposed. The outer layer model is for the site selection and the wind turbine layout optimization. The inner layer model is for the obstacle-avoiding cable routing optimization. In this stage, the seabed terrain is considered for the first time. The proposed integrated model is complex and non-convex. Thus, a hybrid method including an improved ant colony optimization combined with genetic algorithm, dual-simplex method and Kruskal algorithm is proposed to search the solution more efficiently. The initialization stage of the hybrid method is improved from random assignment to directional assignment. The directional solution is obtained by the widely used genetic algorithm. A case study based on a real offshore wind farm is established to prove the effectiveness of the proposed methodology. The results show an over one million dollars increase in annual benefit compared with conventional methods.
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| 10. |
- Yan, Jinyue, 1959-, et al.
(författare)
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Preface
- 2018
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Ingår i: Energy Procedia. - : Elsevier Ltd. - 1876-6102. ; 154, s. 1-2
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Tidskriftsartikel (övrigt vetenskapligt/konstnärligt)
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