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•Coagulation combined with sedimentation and GAC filter dominated the removal of MPs.•Coagulation combined with sedimentation tended to remove MPs in shape of fibres.•GAC filtration ...was prone to remove microplastics in size of 1–5 μm.•The abundance of 1–5 μm MPs from the effluent of ozonation increased by 2.8–16.0%.•A large amount of PAM was detected in the effluent of the sedimentation.
Microplastics (MPs) have attracted worldwide attention as the emerging persistent pollutants. Since they have been detected in raw water and the treated water of drinking water treatment plants (DWTPs), there was an urgent need to explore the properties and fates of microplastics in DWTPs. The characteristics of the effluent MPs from each treatment unit in an advanced drinking water treatment plant (ADWTP) were studied, and the relationship between the variations of MPs and the removal performances of treatment processes was also explored. Overall, both the coagulation combined with sedimentation and the granular activated carbon (GAC) filtration performed well in removing microplastics. The former had a removal efficiency of about 40.5–54.5%, mainly for fibres' removal, and the presence of GAC filtration reduced the microplastic abundance by about 56.8–60.9%, mainly for small-sized MPs. It was worthy of attention that a larger amount of polyacrylamide (PAM) was detected in the effluent of the sedimentation compared to raw water, which was caused by the usage of coagulant containing PAM. Specially, the number of 1–5 μm MPs in the effluent of ozonation tank was increased by 2.8–16.0%, resulting in a negative removal efficiency in ozonation. The removals of microplastics were depended primarily on their physical properties (size and shape).
The indispensable requirement for sustainable development of human society has forced almost all countries to seek highly efficient and cost‐effective ways to harvest and convert solar energy. Though ...continuous progress has advanced, it remains a daunting challenge to achieve full‐spectrum solar absorption and maximize the conversion efficiency of sunlight. Recently, thermoplasmonics has emerged as a promising solution, which involves several beneficial effects including enhanced light absorption and scattering, generation and relaxation of hot carriers, as well as localized/collective heating, offering tremendous opportunities for optimized energy conversion. Besides, all these functionalities can be tailored via elaborated designs of materials and nanostructures. Here, first the fundamental physics governing thermoplasmonics is presented and then the strategies for both material selection and nanostructured designs toward more efficient energy conversion are summarized. Based on this, recent progress in thermoplasmonic applications including solar evaporation, photothermal chemistry, and thermophotovoltaic is reviewed. Finally, the corresponding challenges and prospects are discussed.
This review focuses on recent developments of thermoplasmonics in the solar energy field. The physics fundamentals behind thermoplasmonics are elaborated, basic strategies of material and nanostructured designs toward more efficient photothermal conversion are summarized. Then, recent advances are reviewed for targeted applications including solar evaporation, photothermal chemistry, and thermophotovoltaics. Finally, the corresponding challenges and prospects are discussed.
We present here for the first time the electrochemical behavior of germanium anodes in potassium-ion batteries (KIBs). Nanoporous germanium (np-Ge) samples were fabricated by the chemical-dealloying ...method using Al as the sacrificial metal. Galvanostatic tests identified the reversible potassiation of the np-Ge anodes and the optimal sample with tuned porosities and ligaments demonstrated stable capacities of ~120 mAh g−1 over 400 cycles. Further analysis of the np-Ge electrode revealed amorphous KGe alloys were formed upon discharge. This study suggest germanium can be a potential anode in KIBs, but the structural tailoring is critical to overcome the kinetics problems of the large K-ions.
•Nanoporous germanium with different porous structures have been fabricated via a facile chemical-dealloying approach.•Reversible potassiation have been identified with the Ge anodes in potassium ion cells.•The tailored Ge electrodes with interconnected porosity and small ligaments demonstrate a stable long-term cycling over 400 cycles.
Thermal energy storage system in concentrating solar power plants can guarantee sustainable and stable electricity output in case of highly unstable solar irradiation conditions. In this paper, the ...lumped parameter method is used to develop the models of different thermal energy storage systems. In order to improve the reliability as well as the prediction accuracy of developed models, the charging/discharging process is firstly simulated, and then the dynamic characteristics of thermal energy storage systems are fully tested by imposing 15% step disturbance of mass flow. The results show that the charging/discharging characteristics of the three different thermal energy storage systems are almost the same, which have little to do with the storage mediums used in the systems. Besides, for the representative 1MWe solar parabolic trough power plant, a 15% step up disturbance of oil mass flow will result in a small increase (1.8% and 1.3% respectively) on the outlet temperature of oil and molten salt. On the other side, a 15% step down disturbance of oil mass flow will lead a 2.7% and 2.2% decrease on the outlet temperature of oil and molten salt respectively. In order to verify the validity of the proposed models, the simulation results are compared with both the design points and representative experimental data from the 1MWe solar parabolic trough power plant. The results show that the maximum relative error is not more than 1% when comparing with the design points and the maximum relative error is not more than 12% when comparing with the representative experimental data. Conclusions of this paper are good references for system design, control and commissioning of concentrating solar power plants.
•Thermal energy storage can provide sustainable and stable electricity output.•Lumped parameter method is used to build the model of thermal energy storage.•The dynamic characteristics are tested by a 15% step disturbance of mass flow.•A 15% step-up will result in a 1.3% increase in molten salt outlet temperature.•A 15% step down will result in a 2.2% decrease in molten salt outlet temperature.
Establishing the renewable electricity contribution from solar thermal power systems based on energy analysis alone cannot legitimately be complete unless the exergy concept becomes a part of that ...analysis. This paper presents a theoretical framework for the energy analysis and exergy analysis of the solar power tower system using molten salt as the heat transfer fluid. Both the energy losses and exergy losses in each component and in the overall system are evaluated to identify the causes and locations of the thermodynamic imperfection. Several design parameters including the direct normal irradiation (DNI), the concentration ratio, and the type of power cycle are also tested to evaluate their effects on the energy and exergy performance. The results show that the maximum exergy loss occurs in the receiver system, followed by the heliostat field system, although main energy loss occurs in the power cycle system. The energy and exergy efficiencies of the receiver and the overall system can be increased by increasing the DNI and the concentration ratio, but that increment in the efficiencies varies with the values of DNI and the concentration ratio. It is also found that the overall energy and exergy efficiencies of the solar tower system can be increased to some extent by integrating advanced power cycles including reheat Rankine cycles and supercritical Rankine cycles.
►We presented a theoretical framework for the energy and exergy analysis of the solar tower system. ►We tested the effects of several design parameters on the energy and exergy performance. ►The maximum exergy loss occurs in the receiver system, followed by the heliostat field system. ►Integrating advanced power cycles leads to increases in the overall energy and exergy efficiencies.
► A model for the performances of volumetric solar air receiver was developed. ► Sensitivity studies show the thermal non-equilibrium phenomena are distinct locally. ► The mean cell size has a ...dominant effect on the performances of solar air receiver. ► The solid thermal conductivity of absorber is not important to the air receiver. ► The desired temperature distribution of the absorber is realizable.
Ceramic foams are promising materials for the absorber of volumetric solar air receivers in concentrated solar thermal power (CSP) receivers. The macroscopic temperature distribution in the volumetric solar air receiver is crucial to guarantee that volumetric solar air receivers work steadily, safely and above all, efficiently. This study analyzes the temperature distribution of the fluid and solid phases in volumetric solar air receivers. The pressure drop in the ceramic foams and the interfacial heat transfer between the flowing fluid and solid are included in the model. The radiative heat transfers due to concentrated solar radiation absorption by the ceramic foam and the radiation transport in the media were modeled with the P
1 approximation. The energy fields of the fluid and solid phases were obtained using the local thermal non-equilibrium model (LTNE). Comparison of the macroscopic model with experimental results shows that the macroscopic model can be used to predict the performance of solar air receivers. Sensitivity studies were conducted to analyze the effects of velocity, porosity, mean cell size and the thermal conductivity of the solid phase on the temperature fields. The results illustrate that the thermal non-equilibrium phenomena are locally important, and the mean cell size has a dominant effect on the temperature field.
Porous ceramic foams are used to achieve high performance in solar heat recovery systems. Understanding the convective heat transfer between the air flow and the ceramic foam is of great importance ...when optimising the volumetric air receiver. In this work, the convective heat transfer was numerically studied. The present approach was designed to compute the local convective heat transfer coefficient between the air flow and a porous ceramic foam. For that purpose, the energy balance and the flow inside the porous ceramic foam were solved. In addition, a detailed geometry of the porous ceramic foam was considered. The ceramic foams were represented by idealised packed tetrakaidecahedron structures. The numerical simulations were based on the three dimensional Reynolds-averaged Navier–Stokes (RANS) equations. A sensitivity study on the heat transfer coefficient was conducted with the porosity, velocity and mean cell size as parameters. Based on the numerical simulation results, a correlation for the volumetric local convective heat transfer coefficient between air and ceramic foams was developed. The resulting correlation covers a wide range of porosities, velocities, cell sizes and temperatures. The correlation results were compared with experimental data from the literature, and the comparison shows good agreement. The correlation is intended to be used in the design of volumetric solar air receivers.
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•Bimodal porous carbon with high specific surface area was synthesized.•BPC is beneficial to improve the electrochemical performance of Li-S battery.•The BPC/S cathode exhibits ...outstanding cyclic stability and rate performance.
With the advantages of excellent theoretical specific capacity and specific energy, lithium-sulfur (Li-S) battery is regarded as one of promising energy storage systems. However, poor conductivity and shuttle effect of intermediate electrochemical reaction products limit its application. As good sulfur carriers, porous carbon materials can effectively remit these shortcomings. In this paper, a combination of a hydrothermal KOH activation and successive pyrolysis of biomass reed flowers is proposed to prepare a bimodal porous carbon (BPC) material with high specific surface area (1712.6 m2 g−1). The as-obtained low-cost BPC/S cathodes exhibit excellent cycling performance (908 mAh g−1 at 0.1 C after 100 cycles), good rate capability and cyclability (663 mAh g−1 at 1 C after 1000 cycles), as well as a high areal capacity (6.6 mAh cm−2 at 0.1 C after 50 cycles with a sulfur loading of 8.3 mg cm−2). Such excellent electrochemical performance was mainly ascribed to a specific bimodal porous structure with high specific surface area and plenty spaces for sulfur impregnating, which significantly reduces the escape of polysulfides during cycling and guarantees a good cycling stability. Moreover, the secondary class pores (mesopores and micropores) of the material offer plenty of small channels to improve the electronic and ionic transfer rate and, consequently, to enhance the rate capability. The as-synthesized BPC material presents a great potential as a sulfur carrier material for Li-S battery applications. In this work, we also demonstrate a simple route to develop low-cost carbon materials derived from renewable biomass which may expand and promote their use in energy storage applications.
The coronavirus disease 2019 (COVID-19) pandemic poses a current world-wide public health threat. However, little is known about its hallmarks compared to other infectious diseases. Here, we report ...the single-cell transcriptional landscape of longitudinally collected peripheral blood mononuclear cells (PBMCs) in both COVID-19- and influenza A virus (IAV)-infected patients. We observed increase of plasma cells in both COVID-19 and IAV patients and XIAP associated factor 1 (XAF1)-, tumor necrosis factor (TNF)-, and FAS-induced T cell apoptosis in COVID-19 patients. Further analyses revealed distinct signaling pathways activated in COVID-19 (STAT1 and IRF3) versus IAV (STAT3 and NFκB) patients and substantial differences in the expression of key factors. These factors include relatively increase of interleukin (IL)6R and IL6ST expression in COVID-19 patients but similarly increased IL-6 concentrations compared to IAV patients, supporting the clinical observations of increased proinflammatory cytokines in COVID-19 patients. Thus, we provide the landscape of PBMCs and unveil distinct immune response pathways in COVID-19 and IAV patients.
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•We generated a single-cell atlas of PBMCs in both COVID-19 and influenza patients•Plasma cells increase significantly in both COVID-19 and influenza patients•COVID-19 is featured with XAF1-, TNF-, and FAS-induced T cell apoptosis•COVID-19 activates distinct pathway (STAT1/IRF3) versus influenza (STAT3/NFκB)
COVID-19 and influenza are both respiratory infections with cytokine release syndrome. Zhu et al. use single-cell RNA sequencing of longitudinally collected PBMCs in both patients to reveal distinct immune response landscapes of the two diseases and identify virus-specific cell composition and immune response pathways.
The long-term wind and wave characteristics, and their associated stored power, are investigated in the South China Sea (SCS) from 1986 to 2015. The Weather Research and Forecasting model (WRF) and ...WAVEWATCH-III (WW III) are continuously performed to simulate a 30-year wind and wave hindcasts in the entire domain. Comparisons between the simulated and observed wind and wave data show good agreement under extreme typhoon conditions as well. The spatio-temporal patterns of annual, seasonal and monthly averaged wind fields and wind power density, significant wave heights, and wave potential are presented using the 30-year simulated results. Our results show that offshore winds and waves, with mean annual energy densities reaching up to 1100 W/m2 and 65 kW/m, respectively, are relatively stronger than they are nearshore or inland. The most abundant power occurs in December and the least abundant appears in May. Furthermore, wind and wave energy roses of average power potential at 15 typical points across the SCS are calculated at length. The dominant directions for both the wind and waves are consistently NNE, NE, and ENE. Additionally, the wave energy is mainly the result of energy periods (between 6 and 11 s) and significant wave heights (between 1 and 6 m).
•30-year wind and wave fields are simulated and validated in the South China Sea.•Annual and monthly wind and wave energy resources are assessed.•Wind and wave statistical characteristics are analyzed.
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