Tunable aptamer-MXene sensing interface for label-free and real-time detection of toxic pollutants in water samples.

Stable and low-cost field-effect transistor (FET)-based biosensors are vital for the on-site detection of toxic pollutants in environmental monitoring applications. In this study, a tunable aptamer-MXene sensing interface was constructed to develop renewable FET biosensors. This was achieved through the reversible disulfide bond (-S-S-) reaction between the SH-TiCT film and thiolated aptamer.

Design of Airborne Large Aperture Infrared Optical System Based on Monocentric Lens.

Conventional reconnaissance camera systems have been flown on manned aircraft, where the weight, size, and power requirements are not stringent. However, today, these parameters are important for unmanned aerial vehicles (UAVs). This article provides a solution to the design of airborne large aperture infrared optical systems, based on a monocentric lens that can meet the strict criteria of aerial reconnaissance UAVs for a wide field of view (FOV) and lightness of airborne electro-optical pod cameras.

Advanced nitrogen removal from landfill leachate via Anammox system based on Sequencing Biofilm Batch Reactor (SBBR): Effective protection of biofilm.

High levels of organics negatively affect Anammox for treating landfill leachate. To enhance the ability of Anammox to survive against adverse environments, a lab-scale two-stage Anammox system using a Sequencing Biofilm Batch Reactor was applied to treat mature landfill leachate under 35°C. Over 107days, with influent total nitrogen (TN) and chemical oxygen demand (COD) concentrations of 3000±100 and 3000±100mg/L, effluent TN was below 20mg/L.

Effect of carbon source type on intracellular stored polymers during endogenous denitritation (ED) treating landfill leachate.

Glycogen accumulating organisms (GAOs) capable of storing organic compounds as polyhydroxyalkanoate (PHA) have been used for endogenous denitritation (ED), but the effect of carbon sources type on nitrogen removal performance of GAOs treating landfill leachate is unclear. In this study, a successful ED system treating landfill leachate (COD/NH4(+)-N (C/N): 4) without external carbon source addition was applied. The mature leachate with C/N of 1 was used as the feeding base solution, with acetate, propionate, and glucose examined as the carbon sources, and their effects on yields and compositions of PHA produced by GAOs were determined and associated with nitrogen removal performance.

Continuous-flow combined process of nitritation and ANAMMOX for treatment of landfill leachate.

Due to the difficulty in removing nitrogen from landfill leachate, a combined continuous-flow process of nitritation and anammox was applied to process mature leachate. The transformation rate of ammonia and nitrite accumulation ratio in A/O reactor were kept above 95% and 92% respectively through associated inhibition of free ammonia (FA) and free nitrous acid (FNA) to NOB. The total nitrogen volumetric load of anammox in an UASB reactor was brought up from 0.

Advanced nitrogen removal via nitrite using stored polymers in a modified sequencing batch reactor treating landfill leachate.

A modified sequencing batch reactor (SBR) operated at the anaerobic-aerobic-anoxic mode was developed in this study to fully utilize the organics in landfill leachate (ammonia concentration of 1000 ± 50 mg N/L and COD/total nitrogen (TN) ratio of 1-4). The unique feature of modified SBR process was the addition of an anaerobic stage after feeding stage, so that microorganisms could store the organics during anaerobic stage and supply the carbon source for endogenous denitritation after aeration stage. The 70-day operational tests showed the effluent TN was below 10 mg N/L at C/N ratio of 4.

Optimization of three-stage Anammox system removing nitrogen from landfill leachate.

Advanced nitrogen removal had been realized from mature landfill leachate via three-stage anaerobic ammonium oxidation (Anammox) system during the previous study. However, the Anammox system was influenced by factors such as influent nitrite and organic concentrations and needed to be optimized. To optimize the Anammox system, this study investigated Anammox Sequence Batch Reactor (ASBR) with different feeding modes and influent organic concentrations.

Nitrogen removal from medium-age landfill leachate via post-denitrification driven by PHAs and glycogen in a single sequencing batch reactor.

An anaerobic/aerobic/anoxic (AOA) process in a sequencing batch reactor (SBR) was proposed to treat typical medium-age landfill leachate without extra carbon addition. In a steady-state, the average removal efficiencies of NH4(+)-N, total nitrogen (TN) and COD were 99.7 ± 0.