Globally increasing concerns have been raised on the high energy consumption and greenhouse gas emissions in conventional municipal wastewater treatment processes over the past decades. In this ...study, a self-sustaining synergetic microalgal-bacterial granular sludge process was thus developed to address these challenges. The results showed that the microalgal-bacterial granular sludge process was capable of removing 92.69%, 96.84% and 87.16% of influent organics, ammonia and phosphorus under non-aeration conditions over a short time of 6 h. The effluent could meet the increasingly stringent discharge standards in many countries worldwide. A tight synergetic interrelationship effect between microalgae and bacteria in granules was essential for such excellent process performance. The stoichiometric and functional genes analyses further revealed that most of organic matter and nutrients were removed through microalgal and bacterial assimilations. Moreover, it was found that there existed a desirable distribution of functional species of microalgae and bacteria in microalgal-bacterial granules, which appeared to be essential for the self-sustaining synergetic reactions and stability of microalgal-bacterial granules. Consequently, this work may offer a promising engineering alternative with great potential to achieve energy-efficient and environmentally sustainable municipal wastewater treatment.
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•A microalgal-bacterial granular sludge process was developed for wastewater treatment.•High removal efficiencies under non-aeration conditions were achievable.•Synergized microalgal photosynthesis and bacterial respiration were established.•Assimilations were demonstrated to be the principle pathway of nutrients removal.•The process appeared to be energy-efficient and environmentally sustainable.
Although the activated sludge process, one of the most remarkable engineering inventions in the 20(th) century, has made significant contribution to wastewater reclamation in the past 100 years, its ...high energy consumption is posing a serious impact and challenge on the current wastewater industry worldwide and is also inevitably linked to the issue of global climate change. In this study, we argued that substantial improvement in the energy efficiency might be no longer achievable through further optimization of the activated sludge process. Instead, we should devote more effort to the development or the adoption of novel treatment configurations and emerging technologies. Of which an example is A-B process which can significantly improve the energy recovery potential at A-stage, while markedly reduces energy consumption at B-stage. Various configurations of A-B process with energy analysis are thus discussed. It appears highly possible to achieve an overall energy gain in WWTPs with A-B process as a core.
Controlling the selectivity in electrochemical CO2 reduction is an unsolved challenge. While tin (Sn) has emerged as a promising non‐precious catalyst for CO2 electroreduction, most Sn‐based ...catalysts produce formate as the major product, which is less desirable than CO in terms of separation and further use. Tin monoxide (SnO) nanoparticles supported on carbon black were synthesized and assembled and their application in CO2 reduction was studied. Remarkably high selectivity and partial current densities for CO formation were obtained using these SnO nanoparticles compared to other Sn catalysts. The high activity is attributed to the ultra‐small size of the nanoparticles (2.6 nm), while the high selectivity is attributed to a local pH effect arising from the dense packing of nanoparticles in the conductive carbon black matrix.
SnO NPs (tin monoxide nanoparticles) supported on carbon black were synthesized and their use in CO2 reduction was studied. High partial current densities for CO formation were obtained using these NPs compared to other Sn catalysts. The high activity is attributed to the ultra‐small size of the nanoparticles (2.6 nm). The high selectivity is attributed to a pH effect arising from dense packing of NPs in the conductive carbon black matrix.
•Feasibility of energy recovery from N2O in biological WWTP was reviewed.•Recoverable energy from N2O was insignificant against in-plant energy consumption.•Costly and complicated harvesting and ...post-purification of N2O were required.•Emission of residual dissolved N2O posed a potent environmental risk.•Further technology development is needed for improving N2O production and recovery.
Currently, the biological wastewater treatment has been challenged by their high energy consumption. An increasing effort has been devoted to exploring energy recovery from nitrous oxide (N2O) as a powerful fuel additive rather than as an unwanted byproduct during biological nitrogen removal. This review aims to offer a holistic and critical analysis of the ideas for N2O production and energy recovery in terms of engineering feasibility, economic viability and environmental sustainability. It turns out that the recoverable energy from N2O produced in municipal wastewater is below 0.03 kWh/m3, which is insignificant compared with the in-plant energy consumption, while complicated process configuration and high cost associated with harvesting and post-purification of N2O will be incurred. An environmental risk related to global climate change due to the emission of residual dissolved N2O is also concerned. Further effort on N2O production and recovery technologies is indeed required to improve the overall energy balance.
Serologic and molecular surveillance of serum collected from 152 suspected scrub typhus patients in Myanmar revealed Orientia tsutsugamushi of genotypic heterogeneity. In addition, potential ...co-infection with severe fever with thrombocytopenia syndrome virus was observed in 5 (3.3%) patients. Both scrub typhus and severe fever with thrombocytopenia syndrome are endemic in Myanmar.
The hydrolysis as an essential step in anaerobic digestion has been commonly evaluated according to the extent of soluble chemical oxygen demand (SCOD) released from biosolids. However, little ...information is currently available for the effect of chemical compositions of SCOD on anaerobic digestion. This study showed that the non-biodegradable, recalcitrant organics in SCOD released from food waste and waste activated sludge pretreated with fungal mash rich in various enzymes were accumulated with the prolonged hydrolysis, while the methane production was closely related to the chemical compositions of the feed. The analyses by excitation emission matrix and size exclusion chromatography-organic carbon detection-organic nitrogen detection clearly revealed that the biodegradability of SCOD and the performance of anaerobic digestion were both determined by the chemical compositions of SCOD. These in turn challenged the present practice with SCOD concentration as a sole indicator in the selection and optimization of the pretreatment methods of biosolids prior to anaerobic digestion. It is expected that this study can offer useful insights into future design, optimization and operation of anaerobic digestion system in consideration of both SCOD concentration and its chemical compositions.
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•Biodegradability of SCOD released from FW and WAS was evaluated.•Non-biodegradable organics in SCOD were accumulated with prolonged hydrolysis.•SCOD is not a suitable parameter to alone determine the AD performance.•The compositions of SCOD have a great impact on the methane yield.
Spontaneous magnetic field generation plays important role in laser-plasma interactions. Strong quasi-static magnetic fields affect the thermal conductivity and the plasma dynamics, particularly in ...the case of ultra intense laser where the magnetic part of Lorentz force becomes as significant as the electric part. Kinetic simulations of giga-gauss magnetic field amplification via a laser irradiated microtube structure reveal the dynamics of charged particle implosions and the mechanism of magnetic field growth. A giga-gauss magnetic field is generated and amplified with the opposite polarity to the seed magnetic field. The spot size of the field is comparable to the laser wavelength, and the lifetime is hundreds of femtoseconds. An analytical model is presented to explain the underlying physics. This study should aid in designing future experiments.
With the speedy evolution of global climate change and water shortage, there is a growing need for the energy and carbon neutral wastewater reclamation technology. To tackle this challenge, an ...innovative anaerobic membrane bioreactor (AnMBR)-biochar adsorption-RO process was developed for reclaiming municipal wastewater to high-grade product water with the aims for achieving the energy and carbon neutrality. It was found that about 95.6% of influent COD was removed by AnMBR with direct generation of biomethane, while ammonium-N in AnMBR permeate was fully recovered through biochar adsorption. The effluent from biochar adsorber with significantly lowered divalent ions concentrations was further reclaimed by RO at reduced cost and energy consumption. The energy demand and the total carbon emissions in the proposed process were estimated to be 0.50 kWh/m3 and 633 g CO2e/ m3 against 0.86 kWh/m3 and 1101 g CO2e/ m3 in the current conventional activated sludge (CAS)-microfiltration-RO process. It was further shown that the ammonium recovery via biochar adsorption could offset about 0.503 kWh/m3 that was originally utilized for chemically producing recovered ammonia by the Haber-Bosch method, equivalent to a carbon offsetting of 498 g CO2e/m3, leading to a net carbon emission of 135 CO2e/m3 in the proposed process, which was only about 12% of that in the current CAS-MF-RO process. These suggested that a carbon-neutral municipal wastewater reclamation might be achievable through concurrent carbon reduction and offsetting, while carbon offsetting via ammonia recovery appeared to be a game-changer towards the carbon-neutral operation. Consequently, it is expected that this study can shed lights on how energy- and carbon-neutrality would be achieved by innovating municipal wastewater reclamation technology.
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Most tumor cells show different metabolic pathways than normal cells. Even under the conditions of sufficient oxygen, they produce energy by a high rate of glycolysis followed by lactic acid ...fermentation in the cytosol, which is known as aerobic glycolysis or the Warburg effect. Lung cancer is a malignant tumor with one of the highest incidence and mortality rates in the world at present. However, the exact mechanisms underlying lung cancer development remain unclear. The three key enzymes of glycolysis are hexokinase, phosphofructokinase, and pyruvate kinase. Lactate dehydrogenase catalyzes the transfer of pyruvate to lactate. All four enzymes have been reported to be overexpressed in tumors, including lung cancer, and can be regulated by many oncoproteins to promote tumor proliferation, migration, and metastasis with dependence or independence of glycolysis. The discovery of aerobic glycolysis in the 1920s has provided new means and potential therapeutic targets for lung cancer.
This work proposes a facile fabrication strategy for thermally conductive graphite nanosheets/poly(lactic acid) sheets with ordered GNPs (o-GNPs/PLA)
via
fused deposition modeling (FDM) 3D printing ...technology. Further combinations of o-GNPs/PLA with Ti
3
C
2
T
x
films prepared by vacuum-assisted filtration were carried out by “layer-by-layer stacking-hot pressing” to be the thermally conductive Ti
3
C
2
T
x
/(o-GNPs/PLA) composites with superior electromagnetic interference shielding effectiveness (EMI SE). When the content of GNPs was 18.60 wt% and 4 layers of Ti
3
C
2
T
x
(6.98 wt%) films were embedded, the in-plane thermal conductivity coefficient (
λ
||
) and EMI SE (EMI SE
||
) values of the thermally conductive Ti
3
C
2
T
x
/(o-GNPs/PLA) composites significantly increased to 3.44 W·m
–1
·K
–1
and 65 dB (3.00 mm), increased by 1223.1% and 2066.7%, respectively, compared with
λ
||
(0.26 W·m
–1
·K
–1
) and EMI SE
||
(3 dB) of neat PLA matrix. This work offers a novel and easily route for designing and manufacturing highly thermally conductive polymer composites with superior EMI SE for broader application.
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