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Identifying the deleterious ecological effects of developments, such as roads, mining, and urban expansion, is essential for informing development decisions and identifying appropriate mitigation actions. However, there are many t...
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Identifying the deleterious ecological effects of developments, such as roads, mining, and urban expansion, is essential for informing development decisions and identifying appropriate mitigation actions. However, there are many types of ecological impacts that slip 'under the radar' of conventional impact evaluations and undermine the potential for successful impact mitigation (including offsets). These 'enigmatic' impacts include those that are small but act cumulatively; those outside of the area directly considered in the evaluation; those not detectable with the methods, paradigms, or spatiotemporal scales used to detect them; those facili-tated, but not directly caused, by development; and synergistic impact interactions. Here, we propose a framework for conceptualising enigmatic impacts and discuss ways to address them.
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Across coastal areas of the northern Gulf of Mexico, the Deepwater Horizon oil spill resulted in significant ecological injury, and over 8 billion USD directed to restoration activities. Oyster restoration projects were implemente...
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Across coastal areas of the northern Gulf of Mexico, the Deepwater Horizon oil spill resulted in significant ecological injury, and over 8 billion USD directed to restoration activities. Oyster restoration projects were implemented with regional goals of restoring oyster abundance, spawning stock, and population resilience. Measuring regional or large-scale ecosystem restoration outcomes challenges traditional project-specific monitoring and outcome reporting. We examine the outcomes of oyster restoration at the project-level and discuss potential pathways to measure progress toward region-level goals. An estimated 15 km~2 of oyster habitat was restored across 11 different estuaries with 62 individual reef footprints created, ranging in size from ~0.2 to 1.45 km~2. Individual sites were distributed across the salinity gradient, and all reefs were subtidal. One-year post-restoration, mean total oyster density across all sites was 53.0 ± 60.7 ind m~2 of which 38.4 ± 42.2 ind m~(-2) were adult (>25 mm shell height) oysters. Recent data (2018/2019) available for all sites indicates reduced densities of total oysters (44.6 ± 70.9 ind m~(-2)) and adult oysters (14.6 ±21.6 ind m~(-2)). These data provide insight into project specific outcomes, suggesting an overall enhancement in oyster abundance compared to pre-restoration, but fall short of informing outcomes at the regional-level that incorporate cumulative effects on adjacent and connected reef populations, or inform overall resiliency of the regional oyster resource. Developing regional outcome benchmarks that enable assessment of cumulative and synergistic impacts of individual projects may benefit from broader spatial and temporal monitoring requirements that can better inform development of regional tools or models. Such tools would enable cumulative effects analyses examining net resource change, resilience and assess impacts of restoration activities on regional resource status.
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It is often recognized, but seldom addressed, that a quantitative assessment of the cumulative effects, both additive and non-additive, of multiple stressors on fish survival would provide a more realistic representation of the fa...
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It is often recognized, but seldom addressed, that a quantitative assessment of the cumulative effects, both additive and non-additive, of multiple stressors on fish survival would provide a more realistic representation of the factors that influence fish migration. This review presents a compilation of analytical methods applied to a well-studied fish migration, a more general review of quantitative multivariable methods, and a synthesis on how to apply new analytical techniques in fish migration studies. A compilation of adult migration papers from Fraser River sockeye salmon Oncorhynchus nerka revealed a limited number of multivariable methods being applied and the sub-optimal reliance on univariable methods for multivariable problems. The literature review of fisheries science, general biology and medicine identified a large number of alternative methods for dealing with cumulative effects, with a limited number of techniques being used in fish migration studies. An evaluation of the different methods revealed that certain classes of multivariable analyses will probably prove useful in future assessments of cumulative effects on fish migration. This overview and evaluation of quantitative methods gathered from the disparate fields should serve as a primer for anyone seeking to quantify cumulative effects on fish migration survival.
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The inhibition process of steel against corrosion in 1.0 M HCl using natural honey in the presence and absence of 0.1 M KI was studied at 25–55 °C utilizing a potentiodynamic polarization, electrochemical impedance spectroscopy ...
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The inhibition process of steel against corrosion in 1.0 M HCl using natural honey in the presence and absence of 0.1 M KI was studied at 25–55 °C utilizing a potentiodynamic polarization, electrochemical impedance spectroscopy (EIS) measurements and gravimetric method. Corresponding surfaces of steel were examined by SEM and EDX techniques. The obtained data demonstrated that inhibition efficiency increased by increasing both natural honey dose and environment temperature. Synergism parameter values were found more than one indicating that the inhibition efficiency of natural honey enhanced by an addition of KI due to synergism. The adsorption of natural honey in the presence and absence of iodide ions on the steel surface was found to follow Langmuir adsorption isotherm.
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China's Carbon dioxide (CO2) emission and fine particulate matter (PM2.5) pollution have drawn widespread attention. Synergistic control of ambient PM2.5 pollution and CO2 emission is the core concern of China's environmental prot...
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China's Carbon dioxide (CO2) emission and fine particulate matter (PM2.5) pollution have drawn widespread attention. Synergistic control of ambient PM2.5 pollution and CO2 emission is the core concern of China's environmental protection at present and in the next stage. This study developed a systematical method for assessing the synergy between PM2.5 pollution and CO2 emission. The methods integrated the assessment of PM2.5-related health impact and social costs for CO2 emission and the PM2.5-CO2 synergy index assessment, supporting a comprehensive evaluation from the perspectives involving absolute quantitative socioeconomic impact and relative bivariate correlation. Furthermore, the synergy between PM2.5 pollution and CO2 emission in 336 Chinese cities is evaluated as a case study. The results show PM2.5 pollution was associated with a total 1516.0 billion Yuan health loss in 336 Chinese cities 2020 while the social costs for CO2 emission were 1081.1 billion Yuan. High PM2.5-related health impacts and CO2 emission-related social costs mainly aggregated in Beijing-Tianjin-Hebei and surrounding areas (BTHS), Yangtze River Delta urban agglomeration (YRD), and specific center cities. The synergies between PM2.5 pollution and CO2 emission were more significant in 2017 and 2018 and key cities. High synergies were observed in the BTHS, the northern part of YRD, the northwest, and Qinghai-Tibet Plateau cities. This study provides a multi-perspective and classifying idea to assess the CO2-PM2.5 synergy while drawing a city-level map of China. The assessment, typological analysis, and synergistic control recommendations can be referenced by other countries that are bothered simultaneously by PM2.5 pollution and CO2 emission.
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Abstract Mechanical resonant designs for oscillating triboelectric nanogenerators (O-TENGs) are effective for boosting output power at a resonant frequency, but there remains room for optimizing output performance because of the v...
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Abstract Mechanical resonant designs for oscillating triboelectric nanogenerators (O-TENGs) are effective for boosting output power at a resonant frequency, but there remains room for optimizing output performance because of the various equivalent resonant designs at the same resonant frequency. Here, we report an optimized resonant design for enhancing the output performance of O-TENGs. We theoretically design O-TENGs with different masses and spring stiffnesses at equal resonant frequencies. The triboelectric outputs of the O-TENGs improve with increasing mass and spring stiffness at the resonant frequency. To understand the enhancing mechanism, the dynamic properties such as velocity, acceleration, and contact load are analyzed. We find that increasing the contact load enhances the triboelectric outputs. In addition, we confirm that increasing the gap distance enhances the triboelectric output, but also that there is an optimal gap distance due to the vibration mode of the O-TENG. Finally, we design a tandem O-TENG with a ground system to harvest broadband vibration energy and to synergistically improve the triboelectric performance. We successfully demonstrate an overall four-fold improvement in the output voltage from 38 to 150 V. We expect that our results can provide critical design rules for effectively boosting and optimizing the output power of O-TENGs.
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A critical infrastructure is a complicated system whose failure (in whole or in part) has a significant impact on national interests, including security, the economy and basic human needs. The system consists of relevant sectors, ...
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A critical infrastructure is a complicated system whose failure (in whole or in part) has a significant impact on national interests, including security, the economy and basic human needs. The system consists of relevant sectors, elements and their mutual linkages. In order to study critical infrastructures, it is necessary to apply a systems approach based on cross-sectoral evaluation and research into the linkages between the individual critical infrastructure sectors. Specifically, it is necessary to describe the individual vertical and horizontal levels of each critical infrastructure and the associated linkages. From this point-of-view, a critical infrastructure is embedded within the broader context of emergencies and enterprises, representing a compact and mutually-interconnected system.
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Abstract Previous studies have revealed that extratropical forcing can lead to changes in the intertropical convergence zone (ITCZ). Based on reanalysis data from 1979 to 2019, this paper discusses the influence of the South Pacif...
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Abstract Previous studies have revealed that extratropical forcing can lead to changes in the intertropical convergence zone (ITCZ). Based on reanalysis data from 1979 to 2019, this paper discusses the influence of the South Pacific Ocean Dipole (SPOD, a dominant mode between the subtropics and extratropics in the South Pacific) and its coordination with ENSO in the ITCZ. Results show that SPOD has an effect on the position and intensity of the ITCZ, especially in the region around Niño4. From the latitudes of ITCZ axes and precipitation averaged over 160°E–160°W, positive (negative) SPOD events force a northward (southward) shift in the ITCZ in boreal winter (DJF), while the position moves in the opposite direction in boreal summer (JJA). In addition, ENSO can obviously enhance the influence of SPOD on the ITCZ. It is evident that there is a wider range of northward (southward) shift in the ITCZ under both positive SPOD and El Niño (negative SPOD and La Niña) conditions during DJF. Similar to DJF, both positive SPOD and El Niño (negative SPOD and La Niña) events still cause the ITCZ to move toward (away from) the equator during JJA, except that the magnitude of the movement in JJA is less than that in DJF. Precipitation averaged over 160°E–160°W is at a maximum under both positive SPOD and El Niño events, which have the greatest influence on ITCZ intensity, followed by both negative SPOD and La Niña in DJF, while in JJA, ITCZ intensity is most sensitive to negative SPOD events.
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The complex interaction between stress concentration and abrasive embedding is a crucial issue in impact-abrasive wear. By comparing with the conventional tempered martensitic steel, this work attempts to find a correlation betwee...
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The complex interaction between stress concentration and abrasive embedding is a crucial issue in impact-abrasive wear. By comparing with the conventional tempered martensitic steel, this work attempts to find a correlation between the microstructure and wear resistance of bainitic steel, synergistically strengthened by TiC and the residual austenite (RA). The wear behaviors and work-hardening characteristics of the two steels vary under different impact loads. Bainitic steel has a preferable wear resistance despite its lower initial hardness. This is mainly attributed to the fact that the RA in bainite steel produces a greater work-hardening effect through the transformation-induced plasticity effect and alleviates crack propagation. At the same time, TiC particles resist abrasive embedding into the matrix and effectively decrease the wear failure caused by micro-cutting.
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The development of a stable, cost-effective and efficient photocatalyst for the detoxification of organic pollutants is significant and has become the main challenge. Herein, two-dimensional (2D)-Ag2O/Co3O4 nanocomposites were syn...
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The development of a stable, cost-effective and efficient photocatalyst for the detoxification of organic pollutants is significant and has become the main challenge. Herein, two-dimensional (2D)-Ag2O/Co3O4 nanocomposites were synthesized via a facile and novel soft chemical procedure in the existence of non-ionic surfactant pluronic F-68 for the first time for utilizing in photodegradation of Foron Blue (FB) dyes. The N-2 isotherms Ag2O/Co3O4 nanocomposites indicated the existence of the IV isotherm type, confirming the formation of mesopores structure. The photodegradation efficiency of Ag2O/Co3O4 nanocomposites is much better than bare Co3O4 NPs, and the 0.9%Ag2O/Co3O4 is considered the optimum one with 100% FB dye degradation after 40 min of illumination. Interestingly, the photodegradation rate over 0.9% Ag2O/Co3O4 nanocomposite was promoted 2.5 times larger than that bare Co3O4 NPs. The highest k(app) values (0.0789 min(-1)) for 0.9% Ag2O/Co3O4 nanocomposites is about 4 times higher than bare Co3O4 (0.0202 min(-1)). The excellent synergistic impact between Ag2O and Co3O4 indicated the advantageous visible-light-induced FB dye degradation efficiency compared with bare Co3O4 NPs. The 0.9%Ag2O/Co3O4 nanocomposite exhibited the highest photocurrent density and lowest PL emission peak under illumination due to the facilitated interfacial hole mobility and prohibited electron recombination. The formation energy bands of Ag2O/Co3O4 with S-scheme junction can suppress photoinduced electron-hole recombination and form more active species for photodegradation of FB dye. It is worth noting that the incorporation of Ag2O NPs at a specific amount is played an essential role in improving the degradation efficiency. In addition, it exhibited excellent durability and stability even after five consecutive cycles.
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