Although scholarly attention towards inclusive economic development is emergent, its concept and evaluation remain ambiguous since few attempts have been made to elaborate on its definitions and ...goals. In this study, we conceptualize and define inclusive economic development, propose a productivity perspective for evaluating it, and construct an inclusive total factor productivity index based on data envelopment analysis. According to the estimation results, we report and map the major findings of our index. The results demonstrate that although inclusive economic development is progressing globally, significant regional disparities persist.
•Anaerobic dynamic membrane bioreactor was used for landfill leachate treatment.•62.2% of COD removal efficiency was achieved at the influent COD 13,000mg/L.•Average methane yield was 0.34L/g ...CODremoved at OLR 4.87kg COD/(m3d).•Archaeal community was stable while changes occurred in the bacterial community.•Genus Methanosarcina was identified as the dominant methanogen in the system.
In this study, a pilot-scale anaerobic dynamic membrane bioreactor was operated for 142days for treating landfill leachate. Under stable operation, average COD removal efficiency of 62.2% was achieved when the reactor was fed with the raw leachate containing total ammonium concentration above 3000mg/L and COD above 13,000mg/L. The methane content in the biogas was in the range of 70–90%, and the average methane yield was 0.34L/g CODremoved at the organic loading rate of 4.87kg COD/(m3d). Pyrosequencing analyses indicated that during the operation the archaeal community was relatively stable while obvious changes took place in the bacterial community. Alkaliphilus, Petrimonas, Fastidiosipila and vadinBC27 were the abundant fermentation bacteria in bacterial communities. Moreover, phylum TM6 gradually became the most dominant bacterial community and reached the highest relative abundance of 32.9% as the operation elapsed. In archaeal communities, genus Methanosarcina was identified as the dominant methanogen.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
Purpose
Carbon trading mechanism has been adopted to foster the green transformation of the economy on a global scale, but its effectiveness for the power industry remains controversial. Given that ...energy-related greenhouse gas emissions account for most of all anthropogenic emissions, this paper aims to evaluate the effectiveness of this trading mechanism at the plant level to support relevant decision-making and mechanism design.
Design/methodology/approach
This paper constructs a novel spatiotemporal data set by matching satellite-based high-resolution (1 × 1 km) CO2 and PM2.5 emission data with accurate geolocation of power plants. It then applies a difference-in-differences model to analyse the impact of carbon trading mechanism on emission reduction for the power industry in China from 2007 to 2016.
Findings
Results suggest that the carbon trading mechanism induces 2.7% of CO2 emission reduction and 6.7% of PM2.5 emission reduction in power plants in pilot areas on average. However, the reduction effect is significant only in coal-fired power plants but not in gas-fired power plants. Besides, the reduction effect is significant for power plants operated with different technologies and is more pronounced for those with outdated production technology, indicating the strong potential for green development of backward power plants. The reduction effect is also more intense for power plants without affiliation relationships than those affiliated with particular manufacturers.
Originality/value
This paper identifies the causal relationship between the carbon trading mechanism and emission reduction in the power industry by providing an innovative methodology for identifying plant-level emissions based on high-resolution satellite data, which has been practically absent in previous studies. It serves as a reference for stakeholders involved in detailed policy formulation and execution, including policymakers, power plant managers and green investors.
All-clamped plate structures are usually subject to strong coupling, model uncertainties and system time-delay. To address these challenges, this work proposes a novel vibration control method based ...on a linear active disturbance rejection controller (LADRC) with time-delay compensation (TDC-LADRC). The mathematical model of the piezoelectric plate is first established based on system identification with an auxiliary variable method. Then ADRC is designed for the delay-free part by a smith predictor with a novel differentiator. An extended state observer (ESO) is drawn to estimate the internal and external disturbances, such as mode errors, higher harmonics and external environmental excitations. Then, real-time compensation is introduced via feed-forward mechanism to attenuate their adverse effects, so that optimal vibration suppression performance can be achieved by the proposed controller. Finally, based on NI-PCIe6343 acquisition card, an experimental set-up is designed to verify and compare the performance of the proposed TDC-LADRC against the traditional LADRC and the traditional predictor based LADRC (PLADRC). Comparative experimental results show that the proposed TDCLADRC possesses the best disturbance rejection and vibration suppression performance.
•A novel ADRC-based active vibration controller is proposed.•The piezoelectric plate is established by an auxiliary variable method.•The ADRC controller attenuates delay by a novel differentiator-based predictor.•ESO is used to estimate and attenuate the internal and external disturbances.•An experimental set-up is designed to verify the superiority of proposed method.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Anaerobic digestion (AD) plays an important role in waste activated sludge (WAS) treatment; however, conventional AD (CAD) process needs substantial improvements, especially for the treatment of WAS ...with low solids content and poor anaerobic biodegradability. Herein, we propose a submerged anaerobic dynamic membrane bioreactor (AnDMBR) for simultaneous WAS thickening and digestion without any pretreatment. During the long-term operation, the AnDMBR exhibited an enhanced sludge reduction and improved methane production over CAD process. Moreover, the biogas generated in the AnDMBR contained higher methane content than CAD process. Stable carbon isotopic signatures elucidated the occurrence of combined methanogenic pathways in the AnDMBR process, in which hydrogenotrophic methanogenic pathway made a larger contribution to the total methane production. It was also found that organic matter degradation was enhanced in the AnDMBR, thus providing more favorable substrates for microorganisms. Pyrosequencing revealed that Proteobacteria and Bacteroidetes were abundant in bacterial communities and Methanosarcina and Methanosaeta in archaeal communities, which played an important role in the AnDMBR system. This study shed light on the enhanced digestion of WAS using AnDMBR technology.
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IZUM, KILJ, NUK, PILJ, PNG, SAZU, UL, UM, UPUK
Fouling caused by soluble microbial products (SMP) in membrane bioreactors (MBRs) is a critical problem, and a general understanding on SMP fouling behaviors has not been well established due to the ...complex interactions between SMP and membranes. In the present work, alginate solution was chosen as a model SMP foulant, and the effects of solution chemistry on the interaction energy between alginate and polymeric membranes were assessed by the extended Derjaguin–Landau–Verwey–Overbeek (XDLVO) theory. The results showed that the pH and ionic strength levels of the solution had significant effects on the solution properties and the interaction energy between alginate and membranes. The free energy of cohesion of alginate was maximal at pH 6.5 and ionic strength 10mM. Either increase or decrease of pH could lessen its cohesion free energy. Increase of ionic strength reduced the free energy of cohesion and made alginate solution more unstable and hydrophobic. Energy barrier between alginate and membranes was reduced under higher ionic strength and acidic condition, which was supported by fouling filtration experiments. It was also found that after the formation of initial fouling layer onto membranes, membrane fouling was controlled by cohesion free energy between approaching alginate and alginate-modified surfaces. This study demonstrated that XDLVO-model is sufficient to assess short-range membrane–foulant interactions and to predict SMP fouling in MBRs.
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•We examine the interaction energy between membrane and alginate by the XDLVO theory.•High ionic strength and strong acidic condition can reduce interaction energy.•Cohesion free energy between alginate and virgin membrane governs initial fouling.•Interactions of foulant and foulant-modified surface dominate after initial fouling.•XDLVO-model can well characterize and predict biofouling behaviors.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
Recently, thin film composite (TFC) polyamide forward osmosis (FO) membranes have received attention for their potential water- and energy-related applications. TFC FO membranes have been shown to ...achieve both higher water flux and better solute rejection than cellulose triacetate (CTA) FO membranes. One of the major obstacles in widespread membrane use is the irreversible fouling that occurs during long-term filtration processes such as wastewater treatment. The development of proper chemical cleaning protocols for TFC FO membranes holds the key to achieving sustainable operation of FO processes. In this study, virgin membrane samples were exposed to chemical cleaning agents to determine their effects on membrane properties. In Addition, the water flux recovery efficiency of selected chemical agents was investigated by measuring the change in water flux following chemical cleaning of fouled membrane samples. Exposure of TFC membranes to commercial cleaning detergents (0.8% EDTA and 1% Alconox mixture) resulted in a dramatic increase in water and solute fluxes. Alkaline soaking led to a slight increase in the relative water and solute fluxes, while acid exposure led to a decrease in these fluxes. It was also found that the changes in membrane properties caused by Alconox exposure were irreversible, while the impacts of alkaline exposure were reversible, demonstrating that the Alconox exposure caused damage to TFC membranes. Various cleaning protocols were then developed and tested on wastewater-fouled TFC membranes. Results indicate that the use of 0.1% NaOH/0.1% sodium dodecyl sulfate (SDS) mixture cleaning followed by acid cleaning with either 2% citric acid or 0.5% HCl was the most effective cleaning strategy.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
This study was conducted to assess the degree of humification in dissolved organic matter (DOM) from different composts, and their environmental impact after soil amending based on fluorescence ...measurements (emission, excitation, synchronous scan, and excitation-emission matrix EEM). The compost sources studied included dairy cattle manure (DCM), kitchen waste (KW), cabbage waste (CW), tomato stem waste (TSW), municipal solid waste (MSW), green waste (GW), chicken manure (CM), and peat (P). Conventional and EEM fluorescence spectroscopy indicated that the DOM of these composts contained compounds similar in structure but comparisons between conventional fluorescence parameters and fluorescence regional integration of EEM fluorescence spectra showed that the DOM was different in degree of humification. Regression analysis demonstrated significant corrections between major fluorescence parameters. In hierarchical cluster analysis, these composts were clustered into 2 groups and 4 subgroups, and projection pursuit regression analysis further ranked the compost sources as KW, CW, P>CM, DCM, TW, GW>MSW in their degree of humification in DOM.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
Ultrasonication has been widely used for bound extracellular polymeric substance (EPS) extraction. However, the used ultrasonic power density is quite different in literature, which makes their ...results non-comparable. In this study, the effects of different ultrasonic power densities on extracting bound EPS were assessed via analyzing carbohydrates, proteins, humic acids and DNA. Experimental results proved that ultrasonication power density had a significant effect on loosely bound EPS (LB-EPS) extraction, and an appropriate power density termed critical power density was found to be 35W/10mL according to the variations of DNA which represented the intactness or damage of cell membrane. Nevertheless, carbohydrates, proteins and humic acids did not change obviously in tightly bound EPS (TB-EPS) until a very high power density was applied. The critical power density was determined as 65W/10mL for TB-EPS extraction. The results indicated that a critical power density should be used in order to extract maximal EPS but not to damage cell membrane intactness.
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•Ultrasonication power density affected LB-EPS extraction significantly.•Power density did not affect TB-EPS extraction until a very high value was used.•DNA evolution could be used to identify the critical power density of EPS extraction.•Critical power density for LB- and TB-EPS extraction was 35 and 65W/10mL, respectively.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
Filtration behaviors, membrane fouling and cleaning were investigated in a forward osmosis (FO) membrane system used to post-treat the effluent of a membrane bioreactor (MBR) fed with landfill ...leachate (LFL). In short-term tests, it was observed that the water flux with the membrane active layer facing the draw solution (AL-DS mode) was lower than that with the membrane active layer facing the feed solution (AL-FS mode) for LFL treatment. Mathematical models could well simulate the flux evolution of AL-FS mode while the flux of AL-DS deviated from the modeling curve, suggesting that fouling could be rapidly developed within 1h filtration for AL-DS mode. During long-term filtration, about 98.6% of COD, 96.6% of TP, and 76.9% of ammonium were rejected by the FO system. A decrease of water flux was also observed with an increase in operation time. Confocal laser scanning microscopy and Fourier transform infrared spectroscopy confirmed the existence of polysaccharides and proteins in the fouling layer. Inorganic fouling was mainly caused by Ca, Na, Mg, K, Si, Fe and Al. It was also found that the effect of cake enhanced concentration polarization played an important role during long-term operation. About 88.9% of the permeate flux was recovered after hydraulic cleaning while it reached 98.9% of the initial flux after chemical cleaning, indicating that chemical cleaning was needed to eliminate irreversible fouling and to recover membrane permeability during long-term operation.
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•An FO system is used for post-treatment of MBR-treated landfill leachate (LFL).•AL-DS mode for FO leads to rapid fouling within 1h for LFL treatment.•About 98.6% of COD, 96.6% of TP, and 76.9% of ammonium are rejected by the FO system.•Chemical cleaning is needed to remove irreversible fouling in long-term filtration.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
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