Publications by authors named "Jae-Kyung Jang"

The current need for the upgradation of biohydrogen generation and contaminant removal in two-chambered microbial electrolysis cells (MECs) compels the design of alternatives i.e. bioelectrochemical systems (BESs) to conventional reactors.

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In this study, iron/iron-magnesium (Fe/Fe-Mg) additives were prepared through the impregnation of granular activated carbon (GAC) with iron and iron-magnesium (GFM) to enhance biohydrogen production. The microscope observation and chemical analysis revealed that the GAC matrixes were well infused with Fe/Fe-Mg, while the X-ray diffraction analysis revealed the species of metal formed on the GAC as Fe and MgH. The synergistic effect of Fe and Mg in GFM allowed it for a shorter delay time and higher hydrogen production rate than other additives, indicating their possible use in stimulating the fast release of hydrogen in anaerobic digestion.

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Microbial electrolysis cells (MECs) have attracted significant interest as sustainable green hydrogen production devices because they utilize the environmentally friendly biocatalytic oxidation of organic wastes and electrochemical proton reduction with the support of relatively lower external power compared to that used by water electrolysis. However, the commercialization of MEC technology has stagnated owing to several critical technological challenges. Recently, many attempts have been made to utilize nanomaterials in MECs owing to the unique physicochemical properties of nanomaterials originating from their extremely small size (at least <100 nm in one dimension).

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During wastewater treatment, microbial electrochemical technologies (METs) are a promising means for in situ energy harvesting and resource recovery. The primary constraint for such systems is scaling them up from the laboratory to practical applications. Currently, most research (∼90%) has been limited to benchtop models because of bioelectrochemical, economic, and engineering design limitations.

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The aim of this work is to study for concurrent harvesting bioelectricity and struvite mineral from mineral rich wastewater containing with nitrogen (N) and phosphorous (P) contents using MFCs and a chemical precipitation system. Whole reaction was constructed to sequentially run hybrid reactor (consisting of MFCs and struvite precipitation), gravitational sedimentation, nitrogen purging and MFCs. The MFCs generated around 6.

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Residual veterinary antibiotics have been detected in livestock wastewater treatment plants. Despite the long retention time, antibiotic treatment efficiency has shown clear limitations. In this study, we evaluated submerged membrane photobioreactors (SMPBR) during sulfonamide antibiotic-containing livestock wastewater treatment under mixotrophic and photoautotrophic conditions.

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We explore the influence of pressure on the magnetic ground state of the heavy-fermion antiferromagnet (ferromagnet) CeAuSb 2 (CeAgSb 2 ) using first-principles calculations. The total-energy differences obtained by including the spin-orbit interactions and the on-site Coulomb potential for the Ce-derived 4-orbitals are necessary to realize the accurate magnetic ground state of CeSb 2 (: Au and Ag). According to our results, the appearance of a new magnetic phase of CeAuSb 2 (CeAgSb 2 ) at the pressure of 2.

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In this work, three multi-electrode-embedded microbial fuel cells (MFCs) were connected sequentially and operated in series and parallel modes, fed by effluent of an anaerobic digester continuously operated using swine wastewater. The anaerobic digester achieved ~0.75 CH L d while removing 71.

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In order to assess the effects of biofilm capacitance on self-recovering voltage reversals, the restored current is determined and compared with the measured biofilm capacitance by analyzing the results of electrochemical impedance spectroscopy. This comparison demonstrates that self-recovering voltage reversals are caused by temporary damage to, and the recovery of, biofilm capacitance which arises due to the ability of redox enzymes in the electron transfer system to temporarily store electrons. Thus, the development of procedures for voltage reversal control and for the maintenance of serially connected microbial fuel cells (MFCs) should take into account such temporary voltage reversal phenomenon.

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Mixotrophic microalgal growth gives a great premise for wastewater treatment based on photoautotrophic nutrient utilization and heterotrophic organic removal while producing renewable biomass. There remains a need for a control strategy to enrich them in a photobioreactor. This study performed a series of batch experiments using a mixotroph, , to characterize optimal guidelines of mixotrophic growth based on a statistical design of the experiment.

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Heat shock protein (Hsp)70 is a molecular chaperone that maintains protein homoeostasis during cellular stress through two opposing mechanisms: protein refolding and degradation. However, the mechanisms by which Hsp70 balances these opposing functions under stress conditions remain unknown. Here, we demonstrate that Hsp70 preferentially facilitates protein refolding after stress, gradually switching to protein degradation via a mechanism dependent on ARD1-mediated Hsp70 acetylation.

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Polyester cloth (PC) was selected as a prospective inexpensive substitute separator material for microbial fuel cells (MFCs). PC was compared with a traditional Nafion proton exchange membrane (PEM) as an MFC separator by analyzing its physical and electrochemical properties. A single layer of PC showed higher mass transfer (.

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Livestock wastewater containing high concentrations of ammonium and nitrate ions was pretreated with microbubbles and an Fe/MgO catalyst prior to its application in microbial fuel cells because high ion concentrations can interfere with current generation. Therefore, tests were designed to ascertain the effect of pretreatment on current generation. In initial tests, the optimal amount of catalyst was found to be 300 g/l.

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In this work, ammonia removal paths in microbial fuel cells (MFCs) under different initial pH conditions (pH 7.0, 8.0, and 8.

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Microbial fuel cells (MFCs) were investigated for use in removing total ammonia nitrogen (TAN) and residual COD from effluent digested in an anaerobic digester (AD) fed with actual swine wastewater for 32 days in batch mode. Cumulative COD removal in the AD was as high as 59,647±2096 mg/L (80.5% removed), whereas TAN removal in the AD was negligible at 296±116 mg-N/L (5.

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ARD1 is an acetyltransferase with several variants derived from alternative splicing. Among ARD1 variants, mouse ARD1(225) (mARD1(225)), mouse ARD1(235) (mARD1(235)), and human ARD1(235) (hARD1(235)) have been the most extensively characterized and are known to have different biological functions. In the present study, we demonstrated that mARD1(225), mARD1(235), and hARD1(235) have conserved autoacetylation activities, and that they selectively regulate distinct roles of ARD1 variants in tumorigenesis.

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A new architecture for a membraneless and single-chambered microbial fuel cell (MFC) which has a unique bipolar plate-electrode assembly (BEA) design was demonstrated. The maximum power of MFC units connected in series (denoted as a stacked MFC) was up to 22.8±0.

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The cathode reaction is one of the most seriously limiting factors in a microbial fuel cell (MFC). The critical dissolved oxygen (DO) concentration of a platinum-loaded graphite electrode was reported as 2.2 mg/l, about 10-fold higher than an aerobic bacterium.

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We introduce a high-performance microbial fuel cell (MFC) that was operated using a 0.1 M bicarbonate buffer as the cathodic electrolyte. The MFC had a 136.

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To scale-up microbial fuel cells (MFCs), installing multiple unit cells in a common reactor has been proposed; however, there has been a serious potential drop when connecting unit cells in series. To determine the source of the loss, a basic stack-MFC (BS-MFC) has been devised, and the results show that the phenomenon is due to ions on the anode electrode traveling through the electrolyte to be reduced at the cathode connected in series. As calculated by means of the percentage potential drop, the degree of potential drop decreased with an increase in the unit-cell distance.

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These studies were conducted to determine the effects of various concentrations of ammonium and nitrate on current generation using dual-cathode microbial fuel cells (MFCs). Current generation was not affected by ammonium up to 51.8+/-0.

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We report the electrochemical characterization and microbial community analysis of closed circuit microbial fuel cells (CC-MFCs) and open circuit (OC) cells continuously fed with propionate as substrate. Differences in power output between MFCs correlated with their polarization behavior, which is related to the maturation of the anodophilic communities. The microbial communities residing in the biofilm growing on the electrode, biofouled cation-exchange membrane and anodic chamber liquor of OC-and CC-MFCs were characterized by restriction fragment length polymorphism screening of 16S rRNA gene clone libraries.

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Propionate was used as fuel to enrich an electrochemically-active microbial consortium in a microbial fuel cell, and the bacterial consortium was analyzed by culture-independent methods including denaturing gradient gel electrophoresis (DGGE) of the 16S rDNA, and by fluorescent in situ hybridization (FISH). MFCs fed with propionate produced a current of 4.88 +/- 0.

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The removal of nitrilotriacetic acid (NTA) was studied under anaerobic conditions using oligotrophic and copiotrophic microbial fuel cells (MFCs) as a novel wastewater treatment process. Over 85% of NTA was removed from oligotrophic MFCs enriched and maintained with fuel containing NTA, whilst the value was around 20% in oligotrophic MFCs fed with NTA-free fuel, and in copiotrophic MFCs enriched with NTA containing fuel. The oligotrophic MFCs generated current with concomitant utilization of NTA when served as the sole organic compound, suggesting that NTA is oxidized its suitability as fuel in the MFCs.

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Studies were made to improve the performance of a microbial fuel cell (MFC) as a biochemical oxygen demand (BOD) sensor. The signal from MFCs decreased in the presence of electron acceptors of higher redox potential such as nitrate and oxygen. The addition of azide and cyanide did not change the signal in the absence of the electron acceptors.

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