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Electrochemical sensors that use screen-printed electrodes with carbon or metal nanomaterials or hybrid materials to improve sensitivity and stability also provide promising detection platforms. This review summarizes the current state of sensor platforms for the on-field detection of mercury with a focus on key features and recent developments. Furthermore, trends for next-generation mercury sensors are suggested based on a paradigm shift to the active integration of cutting-edge technologies, such as drones, systems based on artificial intelligence, machine learning, and three-dimensional printing, and high-quality smartphones.Organic mercury including methyl-mercury and ethyl-mercury (CH3Hg+ and C2H5Hg+) has high toxicity and bio-accumulation, and thus is easy to generate bio-amplification in food chain. Hence, the specific detection of organic mercury has great significance for objectively assessing the health risk of mercury in seafood. We herein designed an aptamer (AS-T7), which consists of a silver nanoclusters (AgNCs) scaffold sequence (AS) and a T-rich sequence (AT7), for simultaneously synthetizing DNA-templated AgNCs and recognizing organic mercury, and further developed a label-free fluorescent method for the sensitive and specific determination of organic mercury (CH3Hg+ and C2H5Hg+ total concentration) by using DNA-templated AgNCs as signal. ACBI1 chemical Without organic mercury, Ag+ in the mixture of aptamer and Ag+ was bond on AS of aptamer to form AS-templated AgNCs after reduction, and thus emitted strong fluorescence. Whereas, in the presence of organic mercury, CH3Hg+/C2H5Hg+ was bond on AT7 of aptamer to generate photoinduced electron transfer (PET) between CH3Hg+/C2H5Hg+ and AS-templated AgNCs, and thus results in fluorescence quenching of AS-templated AgNCs. The fluorescent method could be used to rapidly detect organic mercury with a detection limit of 5.0 nM (i.e. 1.01 ng Hg/g), which meets the U.S. EPA standard of 0.3 mg/kg (wet). The method was successfully used to detect organic mercury in water and fish muscle with a recovery of 96%-104% and an inter-days RSD (n = 5) less then 7%. The success of the study promised a reliable method for rapid and specific detection of organic mercury in environmental and biological samples.Fluid flow through a bed of solid particles is an important process that occurs in full-scale water treatment operations. The Carman-Kozeny model remains highly popular for estimating the resistance across the bed. It is common practice to use particle shape factors in fixed bed state to match the predicted drag coefficient with experimentally obtained drag coefficients. In fluidised state, however, where the same particles are considered, this particle shape factor is usually simply omitted from the model without providing appropriate reasoning. In this research, it is shown that a shape factor is not a constant particle property but is dependent on the fluid properties as well. This dynamic shape factor for irregularly shaped grains increases from approximately 0.6 to 1.0 in fluidised state. We found that unstable packed beds in moderate up-flow conditions are pseudo-fixed and in a setting state. This results in a decreasing bed voidage and simultaneously in a decreasing drag coefficient, which seems quite backwashing procedure, in which turbidity and peaks in the number of particles are reduced with a positive effect on water quality.As a clean and renewable energy, biogas is an important alternative to fossil fuels. However, the high carbon dioxide (CO2) content in biogas limits its value as a fuel. ‘Biogas upgrading’ is an advanced process which removes CO2 from biogas, thereby converting biogas to biomethane, which has a higher commercial value. Microbial technologies offer a sustainable and cost-effective way to upgrade biogas, removing CO2 using hydrogen (H2) as electron donor, generated by surplus electricity from renewable wind or solar energy. Hydrogenotrophic methanogens can be applied to convert CO2 with H2 to methane (CH4), or alternatively, homoacetogens can convert both CO2 and H2 into value-added chemicals. Here, we comprehensively review the current state of biogas generation and utilization, and describe the advances in biological, H2-dependent biogas upgrading technologies, with particular attention to key challenges associated with the processes, e.g., metabolic limitations, low H2 transfer rate, and finite CO2 conversion rate. We also highlight several new strategies for overcoming technical barriers to achieve efficient CO2 conversion, including process optimization to eliminate metabolic limitation, novel reactor designs to improve H2 transfer rate and utilization efficiency, and employing advanced genetic engineering tools to generate more efficient microorganisms. The insights offered in this review will promote further exploration into microbial, H2-driven biogas upgrading, towards addressing the global energy crisis and climate change associated with use of fossil fuels.A 300m3/d demonstration project of soybean-process wastewater has been established recently with a Spiral Symmetric Stream Anaerobic Bioreactor (SSSAB) as the core. In order to obtain the optimal operation strategy for a full-scale SSSAB and to make it run efficiently and stably in a demonstration project, a Pilot-scale SSSAB (P-SSSAB, effective volume 100 L) was performed for the treatment of soybean-process wastewater over 216 days. The volumetric load rate (VLR) range of the P-SSSAB was 0.32~27.17 kg COD/(m3·d), where the highest VLR [27.17 kg COD/(m3·d)] was 2.01 times to the highest value [13.5 kg COD/(m3·d)] reported. The pH and VFA/ALK of the effluent from the P-SSSAB were in the range of 6.9 up to 9.2 and 0.03 up to 0.17, respectively. The methane yield of the P-SSSAB increased from 0.03 m3/kg COD to 0.47 m3/kg COD, which was 3.36 times to the maximum value (0.14 m3/kg COD) reported. To meet the influent requirement of the aerobic biological treatment in demonstration project (influent COD ≤ 1.5 g/L),n of the methane has been increased significantly, such as the bacteria Syntrophomonas and archaea Methanosaeta.