Illa Mani Pujitha, Mudrika Khandelwal, Chandra Shekhar Sharma

ECS Meeting Abstracts • 2018

Despite recent developments at lab-scale, Lithium ion is still fastest growing and most promising technology for rechargeable batteries. Although graphite has been conventionally used as anode materials in commercial Li ion batteries, a lot of other allotropes of carbon have also been explored in literature. Carbon nanofibers (CNF) based anode which are primarily derived from polymer precursors such as PAN, SU-8 negative photoresist, cellulose acetate is one such example. However, there is still a need to look for alternative precursors to yield CNF on commercial basis using a scalable, low-cost and sustainable route. Bacterial cellulose, a β-1,4 linked exopolysaccharide which is produced by some special kind of obligate aerobic bacteria is one such potential precursor. Bacterial cellulose which is devoid of lignin, hemicellulose and pectin unlike plant cellulose, comprises three-dimensional (3-D) inter woven nanofibrous network. Bacterial cellulose has several unique properties like higher degree of crystallinity, greater mechanical properties and modability. The fiber morphology and porosity of bacterial cellulose can be controlled to a great extent by employing different fermentation conditions, post treatment (drying and purification) and modifying the network formation by additives in fermentation media. Recent advances not only allows in-situ modification of bacterial cellulose properties using additives but also there are few reports on controlling the orientation and patterning of bacterial cellulose nanofibrils. However there are only few recent studies on exploring the bacterial cellulose as a polymer precursor to carbon upon controlled pyrolysis and to use them as anode. There is still a gap towards the integration of modifying the structural properties of bacterial cellulose and to correlate its effect on as-derived CNF and to further evaluate their electrochemical performance. This work is an effort toward this objective. In the present work, we will first discuss the fermentative production of bacterial cellulose, influence of bioprocess parameters and post production treatments on its physiochemical properties, followed by controlled pyrolysis to yield bacterial cellulose derived CNF. Average diameter of bacterial cellulose CNF was in the range of 20-50 nm. Depending on the fermentation media and growth conditions, crystallinity of bacterial cellulose and its derived carbon can be tuned to a great extent. These bacterial cellulose derived CNF were then used as an anode in half-cell configuration to investigate their electrochemical performance. We shall also present the way forward to explore the in-situ modification of bacterial cellulose to further provide a tight control on the physiochemical properties of CNFs upon pyrolysis with the perspective of their utilization as high performance anode for lithium-ion batteries. Given the scalability and relative low cost production of bacterial cellulose and as-derived CNFs may pave the way of their utilization for commercial electrodes in future. Figure 1

Poulomi Chandra, Anoop Verma, Aastha Palta et al.

Research Square • 2025

Abstract A novel electrooxidation (EO) unit was investigated for disinfecting wastewater, offering a promising alternative. This study continuously treated simulated bacterial wastewater using a mixed metal oxide (MMO) anode, mimicking hospital ward conditions. Optimal disinfection (96% bacterial inactivation) was achieved in continuous mode at a current density of 7.14 mA/cm 2 , 0.2 g/L NaCl, 9 minutes treatment time, and 40 mL/min flow rate. Real sewage wastewater achieved 92% inactivation at 8 minutes under these conditions. The MMO anode remained durable and effective after 300 cycles. EO presents a robust and affordable technology with an electrical consumption of 0.184 kWh/m 3 and an operational cost of $1.88/m 3 . These findings suggest this EO technique is a viable approach for decentralized wastewater treatment in hospital infectious wards, with the potential for real-world application.

Erik Lindemann, Inês Didier, Uwe Schröder

ChemElectroChem • 2025

In 1991, Habermann and Pommer published their work on a microbial fuel cell based on sulfide (S 2− ) mediation at cobalt hydroxide modified graphite anodes. Despite the promising character of the presented concept, literature does not show any follow‐up study or successful reproduction of the results. The common denominator among all further studies that involve sulfide oxidation is the working electrode: The use of plain graphite instead of cobalt impregnated graphite results in irreversible electrode blockage by build‐up of elemental sulfur ( S 0 ). In this—purely abiotic—study, the electrochemical properties of cobalt‐deposited electrodes are investigated when brought in contact with sulfide‐containing solutions. This study thereby shows that cobalt acts as a catalyst accelerating the oxidation of S 2− to higher oxidation products, thereby avoiding sulfur build‐up on the electrode surface. The sulfide oxidation can proceed directly at the cobalt oxide surface, or via a soaking and subsequent oxidation mechanism. In this process, the cobalt layer itself is “charged” by transformation to cobalt sulfide (CoS), which is subsequently “discharged” oxidatively resulting in the production of current. The insights presented here pave the way for a replication and utilization of the original results by Habermann and Pommer.

Carlo Santoro, Sofia Babanova, Baikun Li et al.

ECS Meeting Abstracts • 2014

MFC is a promising bio-electrochemical device capable of converting organic compounds (e.g. organic wastes) into useful electricity. In single chamber microbial fuel cells (SCMFCs), the anode is immersed in a solution containing organics that are oxidized and converted by the anodophillic bacteria attached at the anode, and the cathode is exposed to air for oxygen reduction reaction (ORR). As in nature, oxygen is the most preferable final electron acceptor due to its high reduction potential (~0.62 V vs Ag/AgCl at pH=7). The most common cathodes used in SCMFCs need noble catalyst (e.g. platinum) to achieve low overpotentials and subsequently high Open Circuit Potentials (OCP) of 0.3-0.4 V vs Ag/AgCl 1 . But even those cathodes often suffer severe potential losses especially at low current densities 2 . On the other hand, it has been found and routinely proved that air-breathing enzyme-based cathodes exploring birilubin oxidase (BOx) could achieve a cathode OCP higher than 0.5 V vs Ag/AgCl due to the low overpotential and high kinetics of the enzymatic catalyzed reactions 3 . The concept of a Hybrid MFCs had been previously proved and studied in two-chamber MFC 4 . For the first time, hybrid membraneless SCMFCs with microbial-based anode and enzyme-based cathode (BOx) were developed in this study and explored for high power generation. Air-breathing gas-diffusional cathode were prepared using 30%wt PTFE treated carbon cloth (Fuel Cell Earth) as current collector and cathode support. Teflonized carbon black (Vulcan XC72R with 35%wt PTFE was utilized as a gas-diffusional layer. The inner side of the teflonized carbon black (XC35) was additionally pretreated to achieve a gradient from hydrophobic to hydrophilic properties across the layer. The carbon cloth, the XC35 layer and a multi-walled nanotube paper (MWNTP) were fused together by hydraulic pressure. The MWNTP was used to support the catalytic layer on which BOx dissolved in phosphate buffer solution (PBS) was applied and then kept at 4 o C for 16 hours for enzyme immobilization. Membraneless and membrane-based (Nafion 117) SCMFC configuration was studied and compared in this experimentation. SCMFCs (volume of 130 ml) fed with PBS and NaOAc were run in a batch mode for a week. The batch mode SCMFC tests showed that the cathode OCP was higher than 0.5 V vs Ag/AgCl in all SCMFCs tested and stabilizes for an hour. The initial cathode polarization curves showed low overpotentials and ohmic resistances at low current generation (Figure 1a). All cathodes had significantly higher performances in comparison to the Pt-based cathode till 0.2 V vs. Ag/AgCl. Greater ohmic and mass-transfer losses during the cathode polarization were observed when a polymeric membrane (Nafion 117) was used. Markedly high power densities (referred to geometric cathode area) up to 200 μW/cm 2 (2 W/m 2 ) were reached in membraneless SCMFCs with PBS and sodium acetate (Figure 1b). When a polymeric membrane (Nafion 117) was applied in SCMFCs, the power generation dropped to 24-26 μW/cm 2 (0.24-0.26 W/m 2 ), which is most likely due to increased ohmic and diffusional losses given by the presence of a solid barrier. This study showed the possibility of using enzymatic cathode (bilirubin oxidase) in membraneless SCMFCs with high power generation. The highest power density (2 W/m 2 ) ever reported in a single bottle MFC fed with acetate in phosphate buffer was achieved in this study. The main problem related with the exploration of enzymatic electrodes in wastewater MFCs is the enzymes short lifetime and deactivation cased from contaminants in the wastewater. Further studies should be conducted in order to enhance the lifetime and the long-term operation efficiency of the developed enzymatic MFCs. References: 1 Zhang, F., Cheng, S., Pant, D., Van Bogaert, G., Logan B.E., (2009). Electrochemistry Communications, 11, 2177–2179 2 Rismani-Yazdia, H., Carverb, S.M., Christya, A.D., Tuovinen, O.H. (2008). Journal of Power Sources, 180, 683–694. 3 Higgins, S.R., Lau, C., Atanassov, P., Minteer, S.D., Cooney, M.J. (2011). ACS Catal., 1, 994–997 4 Ciniciato G.P.M.K., Lau, C., Cochrane, A., Sibbett, S.S., Gonzalez, E.R., Atanassov, P. (2012). Electrochimica Acta, 82, 208-213

Rachel Yoho, Bradley Lusk, Sudeep Popat et al.

ECS Meeting Abstracts • 2016

Anode-respiring bacteria (ARB) catalyze the complete oxidation of organic compounds (e.g. acetate, glucose) into electrical current and carbon dioxide. ARB naturally produce a biofilm at the electrode surface of up to 100 micrometers, where even cells on the outer part of the biofilm are participating in current production. The specific pathway by which ARB transport electrons intra- and extracellularly is still largely unknown. This is largely due to the fact that many ARB have redundant respiratory mechanisms, leading to a large set of possible proteins involved in these mechanisms. Our research utilizes a variety of electrochemical techniques in order to characterize electron transport responses from various ARB. Our goal is to provide insights into the possible mechanisms of electron transfer from the electrochemical responses of ARB biofilms. Through these experiments, we have observed a complex response to anode potential that allows ARB, such as G. sulfurreducens , to optimize their efficiency in electron transport. In G. sulfurreducens , two pathways were identified for anode respiration with midpoint potentials of – 0.155 ±0.005 and –0.095 ± 0.003 V versus SHE. G. sulfurreducens can shift between these two pathways depending on the anode potential in order to optimize its energy recovery from anode respiration. Pathway shifts were observed within 5-20 minutes of a shift in anode potential, suggesting that this microorganism has a potential-sensing mechanism. The fast shifts also confirm that the slow-scan cyclic voltammograms (~1 mV/s or slower) commonly performed in our field can be the result of transient responses by ARB, who can shift pathways within the experimental time. Multiple redox pathways have also been observed in thermophile T. ferriacetica and alkaliphile Geoalkalibacter ferrihydriticus , suggesting that most ARB can have multiple anode-respiration pathways. While the topic of electron transport is the focus of most ARB research, ionic transport is an important factor in determining rate-limiting and potential loss processes. ARB require near-neutral pH in the medium to grow, differing from chemical fuel cells commonly employed, which run under acidic or alkaline conditions. This pH requirement results in a major transport limitation, as H + ions (now in mM range) should be transported from anode to cathode to achieve electron neutrality. In an MXC anode, H + ions accumulate in the ARB biofilm, creating an acidification that limits current generation. This behavior has been observed with several ARB, including T. ferriacetica and Glk. ferrihydriticus . Through these experiments, we determined that the rate-limiting protein that is responsible for the potential response of ARB is a proton-coupled reaction. Experiments at different pH values result in shifts in the midpoint potential response of ARB, suggesting a proton coupled redox reaction. The specific stoichiometry of the reaction is difficult to elucidate since the H + accumulation in the biofilm causes a pH gradient. Nonetheless, our studies provide insights into the characteristics of the rate-limiting proteins in anode respiration which are yet to be identified.

Juan Esteban Velez, Carlos Sanchez

ECS Transactions • 2013

The electrical energy generation from biodegradable waste, has been gainingground due the growing demand of this resource and the environmental impactassociated. The latter creates a paradox, from one side we have the satisfaction of theenergy demand, in other hand we create a problem that in long term could be worst, forexample the contamination of the soil, air and water by the use of toxic products(petroleum, carbon, uranium, etc.) in order to satisfy the growing demand. In that way themicrobial fuel cells, try to solve both problems at the same time, generating electricalenergy by oxidation of waste water and treat it in the process, reducing the organicloading (8). However, this technology is far from be perfect, because of the low powergeneration, that is not near to satisfy the actual energy demand. This work is looking tomodel the anode of a MFC from thermodynamics of irreversible process theory thisbecause of the need to taking account the fluxes and forces behind the behavior showedby these devices that arise from the two thermodynamic laws, in order to theorize aboutthis phenomena and to define the most appropriate parameters that make possible anoptimal performance. The main goal of this work is to open a new methodology of designMFC to treat the water of streams in the metropolitan area of Medellin, emphasizing inthe improvement of the power level of the cell.

Vibeke B. Karlsen, Gamunu Samarakoon, C. Dinamarca

Linköping Electronic Conference Proceedings • 2022

Sulphide (H2S, HS- and S2-) is an undesired by-product of biogas production processes. This modelling work in Aquasim was carried out to study three parallel processes related to sulphide in AD processes: 1) H2S liquid-gas mass transfer; 2) Acid-base equilibrium; and 3) Sulphide oxidation with three different electron acceptors; nitrate, oxygen, and a biotic anode with a given potential. Multiplicative Monod (biotic processes) and Nernst-Monod kinetics (bioelectrochemical process) provide the basis for the sulphide bio-oxidation processes. At the current stage, the model can be used to study sulphide bio-oxidation and the effect of relevant parameters, including initial biomass concentration, uptake rates, temperature, and pH. The model can be improved further by implementing anaerobic microbial processes as competing reactions. With the proposed improvements, the model can be a useful tool for calculating the chemical dosage or electrode potential required for sulphide removal. These calculations can be based on both the concentration of H2S(g) in the headspace (ppm) often available at full-scale plants and the concentration of sulphide (HS-(liq)) in effluent streams from the plants.

T. Ware, Dustin Simon, K. Hearon et al.

Macromolecular Materials and Engineering • 2012

Planar electronics processing methods have enabled neural interfaces to become more precise and deliver more information. However, this processing paradigm is inherently 2D and rigid. The resulting mechanical and geometrical mismatch at the biotic-abiotic interface can elicit an immune response that prevents effective stimulation. In this work, a thiol-ene/acrylate shape memory polymer is utilized to create 3D softening substrates for stimulation electrodes. This substrate system is shown to soften in vivo from more than 600 to 6 MPa. A nerve cuff electrode that coils around the vagus nerve in a rat and that drives neural activity is demonstrated.

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Global NEST Journal • 2021

Discharging wastewater from industries without any treatment causes environmental pollution and endangers biotic life. In this study, pollutant removal by electrocoagulation (EC) process was investigated using wastewater of the ore processing plant (magnesite crushing and screening plant). In the EC process, iron-iron and copper-copper electrodes were used in parallel in the reactor. Chemical oxygen demand (COD), Sulphate, Chromium (VI), Nickel, Zinc, Magnesium, and Total Suspended Solids (TSS) removals were investigated in the EC process of mineral processing industry wastewater with the iron electrode. These pollutants were calculated as %97.6, %95.1, %98.2, %98.1, %97.8, %88.2, and %98.9, respectively. COD, Sulphate, Chromium (VI), Nickel, Zinc, Magnesium, and TSS removals in the EC process of mineral processing industry wastewater with the copper electrode are %92.8, %94.9, %99.5, %98.7, %96.1, %91.6, and %96.9 respectively. It has been observed that high removal efficiency can be achieved by using the electrocoagulation process in the treatment of ore washing wastewater resulting from the crushing and screening processes in the Chrome Magnesite processing plant.

M. Chandel, P. Kumar, A. Arora et al.

Analytical Chemistry • 2022

Crop diseases cause the release of volatiles. Here, the use of an SnO2-based chemoresistive sensor for early diagnosis has been attempted. Ionone is one of the signature volatiles released by the enzymatic and nonenzymatic cleavage of carotene at the latent stage of some biotic stresses. To our knowledge, this is the first attempt at sensing volatiles with multiple oxidation sites, i.e., ionone (4 oxidation sites), from the phytovolatile library, to derive stronger signals at minimum concentrations. Further, the sensitivity was enhanced on an interdigitated electrode by the addition of platinum as the dopant for a favorable space charge layer and for surface island formation for reactive interface sites. The mechanistic influence of oxygen vacancy formation was studied through detailed density functional theory (DFT) calculations and reactive oxygen-assisted enhanced binding through X-ray photoelectron spectroscopy (XPS) analysis.

Lauren B. Kaiser-Jackson, Markus Dieser, M. McGlennen et al.

ECS Sensors Plus • 2023

During the growth of a polycrystalline ice lattice, microorganisms partition into veins, forming an ice vein network highly concentrated in salts and microbial cells. We used microfabricated electrochemical impedance spectroscopy (EIS) sensors to determine the effect of microorganisms on the electrochemical properties of ice. Solutions analyzed consisted of a 176 μS cm−1 conductivity solution, fluorescent beads, and Escherichia coli HB101-GFP to model biotic organisms. Impedance spectroscopy data were collected at −10 °C, −20 °C, and −25 °C within either ice veins or ice grains (i.e., no veins) spanning the sensors. After freezing, the fluorescent beads and E. coli were partitioned into the ice veins. The corresponding impedance data were discernibly different in the presence of ice veins and microbial impurities. The presence of microbial cells in ice veins was evident by decreased electrical characteristics (electrode polarization between electrode and ice matrix) relative to solid ice grains. Further, this electrochemical behavior was reversed in all bead-doped solutions, indicating that microbial processes influence sensor response. Linear mixed-effects models empirically corroborated the differences in polarization associated with the presence and absence of microbial cells in ice. We show that EIS has the potential to detect microbes in ice and differentiate between veins and solid grains.

R. A. Isibor, A. A. Olaojo, Adetoyese Yomi Oyelade

Ajayi Crowther Journal of Pure and Applied Sciences • 2023

Water is an essential resource for the sustainability of the human race and other biotic lives. This study emerged from variation observed in the groundwater distribution coupled with its quality within the Agudu neighbourhood. This investigation was centred on the geophysical and geochemical characterizations of the aquiferous units. Electrical resistivity method involving Vertical Electrical Sounding (VES) technique and geochemical assessment of groundwater were adopted for the study. A total of twenty VES points were occupied using the Schlumberger electrodes array and the current electrode separation (AB/2) ranged from 2 to 80 m. The data were subjected to both manual processing and computer base iteration using WinResist software. Twenty water samples were collected from wells across the community and subjected to physicochemical assessment. Flame photometry was used in analyzing the cations (Mg2+, Ca2+, Na+ , K+ ) while spectrophotometry was used for chloride, sulphate, bicarbonate, and nitrate. The VES sections revealed two to five geo-electric layers, the weathered and the fractured units were the aquiferous zones. The Dar-Zarrouk parameters were used in establishing the groundwater potential map and classifying the aquifer potential zones. The concentration of major cations was in the order Ca2+>Mg2+>Na+>K+ while that of anions were HCO3>Cl->SO4 -2>NO-3 . The pH values fall within the World Health Organisation’s recommended value, it ranged from slightly acidic to slightly alkaline. All the parameters fall within the permissible level except Ca2+ and water hardness at some locations. The techniques engaged were able to reveal the groundwater distribution and also characterised the chemistry of groundwater.

Ndepana Andrew, Anthony Trofe, Eric Laws et al.

Small • 2025

Abstract The chemistry of the extracellular electron transfer (EET) process in microorganisms can be understood by interfacing them with abiotic materials that act as external redox mediators. These mediators capture and transfer extracellular electrons through redox reactions, bridging the microorganism and the electrode surface. Understanding this charge transfer process is essential for designing biocapacitors capable of modulating and storing charge signatures as capacitance at the electrode interface. Herein, a novel biointerfacial strategy is presented to investigate directional charge injection from a non‐exoelectrogenic living microbe to an electrode surface using the porous metal–organic framework (MOF), MIL‐88B. The biohybrid, formed by interfacing Escherichia coli (E. coli) with MIL‐88B, demonstrates symbiotic interactions between the biotic and abiotic components, facilitating EET from E. coli to the electrode via the MOF. Acting as a redox mediator, the MOF catalyzes E. coli's exoelectrogenic activity, generating distinct charge capacitive signatures at the E. coli‐MOF interface. This system integrates the capacitive signatures resulting from the EET process with the MOF's intrinsic pseudocapacitive properties and surface‐controlled capacitive effects, functioning as a highly efficient biocapacitor. Furthermore, this approach of converting the biochemical energy of a non‐exoelectrogenic microorganism into capacitive signatures opens a new pathway for translating biological signals into functional outputs, paving the way for autonomous biosensing platforms.

Margot Jacquet, Miriam Izzo, Piotr Wróbel et al.

Materials Horizons • 2024

Solar-converting nanosystems using self-renewing biomaterial resources carry great potential for developing sustainable technologies to ameliorate climate change and minimize reliance on fossil fuels. By mimicking natural photosynthesis, diverse proof-of-concept biosolar systems have been used to produce green electricity, fuels and chemicals. Efforts so far have focused on optimizing light harvesting, biocatalyst loading and electron transfer (ET), however, the long-term performance of best-performing systems remains a major challenge due to the intensive use of diffusive, toxic mediators. To overcome this limitation, we developed a rationally designed nanosystem based on the entrapment of non-toxic mediator, ferrocene dimethanol (Fc), localized at the abiotic-biotic molecular interface that efficiently promoted ET between electrode surface and two photosynthetic proteins: cytochrome c and photosystem I. We demonstrate that space-confined Fc mediators (1 nM) are as effective in terms of ET kinetics as a 500 000-fold higher concentration of freely-diffusive Fc. The Fc-confined biophotocathodes showed a milestone photocurrent density of 14 μA cm-2 under oxic conditions compared to analogous planar (2D) biophotoelectrodes, with a photoconductive biolayer stable for over 5 months. The space-confined ET mediation reported in this work opens a new avenue for efficiently interfacing biomachineries, providing a benchmark design advancement in the quest for viable biohybrid technologies.

Jaehyoung Yun, Hyemin Kim, JungMin Kang et al.

ECS Meeting Abstracts • 2024

Over the last decade, various wearable sensor technologies that can monitor human health precisely in real time have extensively been developed. More recently, such wearable biosensor technologies have been employed to observe the condition of plants as well. In particular, a glucose sensor, which has been actively researched for diabetes, can also be applied to plants. A level of glucose concentration in plants indicates cellular metabolic status, biotic and abiotic stress of plants. However, unlike advanced glucose sensors for humans, early glucose sensors based on glucose oxidase are still used in plants glucose monitoring. The enzyme-based glucose sensor has several disadvantages including the stability problem due to denaturation of enzymes and difficulty of immobilizing enzymes on the electrode surface. Additionally, glucose oxidase needs a redox shuttle to transfer electrons, which complicate the sensor manufacturing process. Moreover, H2O2 is generated as a byproduct of glucose oxidase and glucose reaction, which can cause damage to plants and enzymes. In this study, non-enzymatic microneedle (MN) glucose sensor was developed using Co3O4 as a substitute for glucose oxidase. Co3O4 have electrocatalytic properties and chemical stability, showing higher sensitivity compared to glucose oxidase, and is suitable for long-term monitoring. However, it has the disadvantage of low electrical conductivity, making it difficult to transfer electrons, which are generated from the reaction with glucose, to a sensor electrode. Therefore, carbon nanomaterials were mixed to increase electron transfer efficiency and drop casted on the working electrode of a screen-printed sensor. To optimize the ratio of Co3O4 and carbon nanomaterials, the sensitivity was observed by comparing the peak current of cyclic voltammogram and saturation currents of amperogram according to each mixing ratio. Through the analysis results, it was confirmed that 17 wt% carbon nanomaterial had the highest sensitivity of 207 μA/mM cm2. Afterwards, a MN array sensor was fabricated to measure the glucose in plant leaves. MN can penetrate the epidermis of the leaf and enable to measure the glucose from near the phloem of the leaf. MN array structure was fabricated by dispensing SU-8 into a PDMS negative mold and cured by UV exposure. The working and reference electrode of MN array were coated with Co3O4/carbon composite and pseudo-Ag/AgCl ink, respectively, using a pneumatic 3D printer. Pt sputtering was conducted for forming the counter electrode. The metabolism of plants was confirmed by measuring the glucose concentration of leaves at day and night using a MN glucose sensor. References [1] Giraldo, Juan Pablo, et al. Nature nanotechnology 14.6 (2019): 541-553. [2] Teymourian, Hazhir, Abbas Barfidokht, and Joseph Wang. Chemical Society Reviews 49.21 (2020): 7671-7709. [3] Chen, Qianying, et al. Biomacromolecules 23.9 (2022): 3928-3935. [4] Harry, Micaela, et al. Sensing and Bio-Sensing Research 23 (2019): 100262. [5] Perdomo, Sammy A., et al. Biosensors and Bioelectronics 231 (2023): 115300. [6] Jiao, Kailong, et al. Royal Society Open Science 4.12 (2017): 170991.

A. M. Craven, G. Aiken, J. Ryan

Environmental Science & Technology • 2012

The ratio of copper to dissolved organic matter (DOM) is known to affect the strength of copper binding by DOM, but previous methods to determine the Cu(2+)-DOM binding strength have generally not measured binding constants over the same Cu:DOM ratios. In this study, we used a competitive ligand exchange-solid-phase extraction (CLE-SPE) method to determine conditional stability constants for Cu(2+)-DOM binding at pH 6.6 and 0.01 M ionic strength over a range of Cu:DOM ratios that bridge the detection windows of copper-ion-selective electrode and voltammetry measurements. As the Cu:DOM ratio increased from 0.0005 to 0.1 mg of Cu/mg of DOM, the measured conditional binding constant ((c)K(CuDOM)) decreased from 10(11.5) to 10(5.6) M(-1). A comparison of the binding constants measured by CLE-SPE with those measured by copper-ion-selective electrode and voltammetry demonstrates that the Cu:DOM ratio is an important factor controlling Cu(2+)-DOM binding strength even for DOM isolates of different types and different sources and for whole water samples. The results were modeled with Visual MINTEQ and compared to results from the biotic ligand model (BLM). The BLM was found to over-estimate Cu(2+) at low total copper concentrations and under-estimate Cu(2+) at high total copper concentrations.

D. Koutsouras, Leona V. Lingstedt, Katharina Lieberth et al.

Advanced Healthcare Materials • 2019

Electrodes coated with poly(3,4‐ethylenedioxythiophene):polystyrene sulfonate (PEDOT:PSS) have been employed to measure the integrity of cellular barriers. However, a systematic experimental study of the correlation between tissue integrity and impedance of the sensing device has not yet been conducted. Using impedance spectroscopy, how the impedance ratio of the biological tissue to the recording device affects the recording ability of the latter is investigated. PEDOT:PSS‐coated electrodes of various dimensions are employed and the effect of their size to their sensing efficiency is examined. The biotic/abiotic ensemble is modeled with a simple equivalent circuit and an analytical expression of the total impedance as a function of frequency is extracted. The results reveal a critical impedance ratio of the biological tissue to the sensor which allows for efficient sensing of the tissue integrity. This work provides the ground rules for improved impedance‐based biosensors with optimized sensitivity.

Ke Xu, Yinan Yang, Jianfei Ding et al.

Advanced Materials • 2024

The interface between electrodes and neural tissues plays a pivotal role in determining the efficacy and fidelity of neural activity recording and modulation. While considerable efforts have been made to improve the electrode‐tissue interface, the majority of studies have primarily concentrated on the development of biocompatible neural electrodes through abiotic materials and structural engineering. In this study, an approach is presented that seamlessly integrates abiotic and biotic engineering principles into the electrode‐tissue interface. Specifically, ultraflexible neural electrodes with short hairpin RNAs (shRNAs) designed to silence the expression of endogenous genes within neural tissues are combined. The system facilitates shRNA‐mediated knockdown of phosphatase and tensin homolog deleted on chromosome 10 (PTEN) and polypyrimidine tract‐binding protein 1 (PTBP1), two essential genes associated in neural survival/growth and neurogenesis, within specific cell populations located at the electrode‐tissue interface. Additionally, it is demonstrated that the downregulation of PTEN in neurons can result in an enlargement of neuronal cell bodies at the electrode‐tissue interface. Furthermore, the system enables long‐term monitoring of neuronal activities following PTEN knockdown in a mouse model of Parkinson's disease and traumatic brain injury. The system provides a versatile approach for genetically engineering the electrode‐tissue interface with unparalleled precision, paving the way for the development of regenerative electronics and next‐generation brain–machine interfaces.

V. Sankar, E. Patrick, Robert Dieme et al.

Frontiers in Neuroengineering • 2014

Changes in biotic and abiotic factors can be reflected in the complex impedance spectrum of the microelectrodes chronically implanted into the neural tissue. The recording surface of the tungsten electrode in vivo undergoes abiotic changes due to recording site corrosion and insulation delamination as well as biotic changes due to tissue encapsulation as a result of the foreign body immune response. We reported earlier that large changes in electrode impedance measured at 1 kHz were correlated with poor electrode functional performance, quantified through electrophysiological recordings during the chronic lifetime of the electrode. There is a need to identity the factors that contribute to the chronic impedance variation. In this work, we use numerical simulation and regression to equivalent circuit models to evaluate both the abiotic and biotic contributions to the impedance response over chronic implant duration. COMSOL® simulation of abiotic electrode morphology changes provide a possible explanation for the decrease in the electrode impedance at long implant duration while biotic changes play an important role in the large increase in impedance observed initially.

Belkacem El Amrani

Preprints.org • 2024

Ectomycorrhizal (EM) associations are essential symbiotic relationships that contribute significantly to the health and functioning of forest ecosystems. This review examines the biotic factors that influence EM associations, focusing on plant and fungal diversity, host specificity, and microbial interactions. Firstly, the diversity of host plants and ectomycorrhizal fungi (EMF) is discussed, highlighting how the richness of these organisms affects the formation and success of EM symbioses. Next, host specificity is explored, with a focus on the complex relationships between EMF and their host plants. Microbial interactions are examined in depth, with sections on both positive and negative influences of bacteria and different fungal groups on EM formation. Overall, this review provides a comprehensive overview of the biotic factors that shape EM associations, offering insights into the mechanisms that underpin these critical ecological interactions and their broader implications for ecosystem management and restoration.

, Vamsi J. Nalam

• 2012

The activity of plant 9-lipoxygenases (LOXs) influences the outcome of Arabidopsis thaliana interaction with pathogen and insects. Evidence provided here indicates that in Arabidopsis, 9-LOXs facilitate infestation by Myzus persicae, commonly known as the green peach aphid (GPA), a sap-sucking insect, and infection by the fungal pathogen Fusarium graminearum. in comparison to the wild-type plant, lox5 mutants, which are deficient in a 9-lipoxygenase, GPA population was smaller and the insect spent less time feeding from sieve elements and xylem, thus resulting in reduced water content and fecundity of GPA. LOX5 expression is induced rapidly in roots of GPA-infested plants. This increase in LOX5 expression is paralleled by an increase in LOX5-synthesized oxylipins in the root and petiole exudates of GPA-infested plants. Micrografting experiments demonstrated that GPA population size was smaller on plants in which the roots were of the lox5 mutant genotype. Exogenous treatment of lox5 mutant roots with 9-hydroxyoctadecanoic acid restored water content and population size of GPA on lox5 mutants. Together, these results suggest that LOX5 genotype in roots is critical for facilitating insect infestation of Arabidopsis. in Arabidopsis, 9-LOX function is also required for facilitating infection by F. graminearum, which is a leading cause of Fusarium head blight (FHB) disease in wheat and other small grain crops. Loss of LOX1 and LOX5 function resulted in enhanced resistance to F. graminearum infection. Similarly in wheat, RNA interference mediated silencing of the 9-LOX homolog TaLpx1, resulted in enhanced resistance to F. graminearum. Experiments in Arabidopsis indicate that 9-LOXs promote susceptibility to this fungus by suppressing the activation of salicylic acid-mediated defense responses that are important for basal resistance to this fungus. the lox1 and lox5 mutants were also compromised for systemic acquired resistance (SAR), an inducible defense mechanism that is systemically activated throughout a plant in response to a localized infection. the lox1 and lox5 mutants exhibited reduced cell death and delayed hypersensitive response when challenged with an avirulent strain of the bacterial pathogen Pseudomonas syringae pv tomato. LOX1 and LOX5 functions were further required for the synthesis as well as perception of a SAR-inducing activity present in petiole exudates collected from wild-type avirulent pathogen-challenged leaves. Taken together, results presented here demonstrate that 9-LOX contribute to host susceptibility as well as defense against different biotic stressors.

A E Nicholson, N J Mayne

Monthly Notices of the Royal Astronomical Society • 2023

ABSTRACT The search for biosignatures necessitates developing our understanding of life under different conditions. If life can influence the climate evolution of its planet then understanding the behaviour of life-climate feedbacks under extreme conditions is key to determine the ‘edges’ of the habitable zone. Additionally understanding the behaviour of a temperature limited biosphere will help towards formulating biosignature predictions for alien life living under conditions very different to those on Earth. Towards this aim, we extend the ‘ExoGaia Model’ – an abstract model of microbial life living on a highly simplified zero-dimensional planet. Via their metabolisms, microbes influence the atmospheric composition and therefore the temperature of the planet and emergent feedback loops allow microbes to regulate their climate and maintain long-term habitability. Here, we adapt the ExoGaia model to include temperature adaptation of the microbes by allowing different species to have different temperature ‘preferences’. We find that rather than adapting towards the planet’s abiotic conditions the biosphere tends to more strongly influence the climate of its planet, suggesting that the surface temperature of an inhabited planet might be significantly different from that predicted using abiotic models. We find that the success rate for microbial establishment on planets is improved when adaptation is allowed. However, planetary abiotic context is important for determining whether overall survival prospects for life will be improved or degraded. These results indicate the necessity to develop an understanding of life living under different limiting regimes to form predictions for the boundaries of the habitable zone.

Nripendra Laskar

• 2017

“The present book "Current Trends in Global Environment" deals with each and every important and recent issue of environment with clear-cut facts in a lucid manner of presentation, which are likely to be come across by its readers, irrespective of their discipline. An attempt has been made to present the matter in a perceptible and comprehensible manner which would be equally important to a beginner and specialist. Worthy for a reference for its up-to-date content that satisfy its user in a minimum of time. By far majority of books are from the mainstream with heavy a textual load. It has s on present day burning topics like The Greenhouse Effect, Natural Disasters i.e., Tsunami, Earthquake, Continental Drift, Sustainable Environment, Space Ecology, The Glossary will be useful for an individual new to the subject and anyone inexperienced in dealing with some aspects of the subjects. The index has been designed with upper most principle that it should be as complete as possible, of words and short phrases as they naturally appear in related species. We hope that his Global publication by a global famed personality will fit the subject gap for the readers and above all institutional libraries.

Eric Post

Princeton University Press eBooks • 2013

Rising temperatures are affecting organisms in all of Earth's biomes, but the complexity of ecological responses to climate change has hampered the development of a conceptually unified treatment of them. In a remarkably comprehensive synthesis, this book presents past, ongoing, and future ecological responses to climate change in the context of two simplifying hypotheses, facilitation and interference, arguing that biotic interactions may be the primary driver of ecological responses to climate change across all levels of biological organization. The author's synthesis and analyses of ecological consequences of climate change extend from the Late Pleistocene to the present, and through the next century of projected warming. The book's investigation is grounded in classic themes of enduring interest in ecology, but developed around novel conceptual and mathematical models of observed and predicted dynamics. Using stability theory as a recurring theme, the book argues that the magnitude of climatic variability may be just as important as the magnitude and direction of change in determining whether populations, communities, and species persist. It urges a more refined consideration of species interactions, emphasizing important distinctions between lateral and vertical interactions and their disparate roles in shaping responses of populations, communities, and ecosystems to climate change.

Dong Suk Han, Celal Erbay, Choongho Yu et al.

Qatar Foundation Annual Research Conference Proceedings Volume 2016 Issue 1 • 2016

In the past decades, microbial fuel cells (MFCs) have been intensively studied in order to provide sustainable and environmentally friendly wastewater treatment concurrent with energy harvesting. A highly porous, highly efficient, light-weight, and inexpensive 3D sponges consisting of interconnected carbon nanotubes (CNTs) were developed as anodes of MFCs in order to allow more efficient microbe-to-anode electron transfer that are key to the operation of MFCs. The MFCs equipped with the 3D CNT sponge anode generates high power densities of 2150 Wm –3 (per anode volume) or 170 Wm –3 (per anode chamber volume), comparable to those of commercial 3D carbon felt electrodes under the same conditions (1). The high performances are due to excellent charge transfer between CNTs and microbes, which is evident by the 13 times lower charge transfer resistance compared to that of carbon felt. The 3D CNT sponges produced here has low cost (∼$0.1/gCNT) and high production rate (3.6 g/hr) compared to typical production rate of 0.02 g/hr of other CNT-based materials (1). The high production rate and low cost of this highly efficient electrode material can make MFCs more feasible to be scaled up for various applications such as desalination of seawater or saline water. Also, other electrode materials were compared to the 3D CNT sponge in evaluating the efficiency of the MFC and extending the use of these electrode materials to a field of microbial desalination cell (MDC). Once MDCs are applied to the desalination process, there are several challenges that need to be addressed. First, a pH gradient forms between anode and cathode chambers (due to proton accumulation in the anode chamber and hydroxyl ion accumulation in the cathode chamber). In addition, chloride ion accumulation inhibits the activities of electrochemically active microbes. Together these activities degrade the overall performance of the system. Recirculation of the anolyte and catholyte provides one solution to addressing this challenge. However, this approach results in lower Coulombic efficiency. Here, we studied to develop a modified three-chamber configuration where part of the anode chamber and part of the cathode chamber are directly connected through a cation exchange membrane, thus partially allowing transport of protons between the chambers, and thereby limiting the drop in pH, while still maintaining charge differences that drive Cl – and Na + ions to move from seawater to the anode and cathode chambers. Practical MDCs require continuous or batch-mode feeding of wastewater into the anode chambers of the system, thus accumulated chloride ions will be simply flushed out or diluted due to the influx of new wastewater or catholyte. This aspect will mitigate the impacts of the chlorine ion accumulation problem. Also, a pivotal performance limitation centers on the cathode catalyst layer owing to sluggish kinetics of the oxygen reduction reaction and several transport losses. On the cathode side, expensive precious metal catalysts have been used in conventional systems to overcome the slow reactions on the electrode. Platinum and Pt-based electrocatalysts, commonly used in the electrodes, not only contribute to high fuel cell cost but also lead to durability concerns in terms of Pt cathode oxidation, catalyst migration, loss of electrode active surface area, and corrosion of the carbon support. So, this study used Pt-free 3D carbon-based cathode for MDC system. Reference [1] Celal Erbay, Gang Yang, Paul de Figueiredo, Reza Dadr, Choongho Yu, Arum Han, “Three-dimensional porous carbon nanotube sponges for high-performance anodes of microbial fuel cells”, Journal of Power Sources, (2015), 177–183.

Andrew Needham

Power Lines • 2014

This chapter addresses how The New York Times challenged the long-held claims of Arizona officials that their state was entitled to a portion of the Colorado River by rights, a claim recently upheld by the Supreme Court. The paper also argued that Arizona's attempt to realize those claims endangered the Colorado River and the Grand Canyon itself. Transforming the flowing energy of water into flowing electricity, the Times suggested, was not in the national interest. Such critiques of Arizona's growth emerged in the wake of the Interior Department's development of the Pacific Southwest Water Plan, a plan designed in 1963 to realize Arizona's Colorado River claims. The critiques emerged from several different conservationist groups, but most powerfully from the Sierra Club, which was gradually changing the description of its politics from “conservation” to “environmentalism” and assuming a far more public voice in disputes over the proper use of public lands.

Kyung Lee, Keum Sook Kim, suw young Ly

Preprints.org • 2024

Background/Objective: In-vivo diabetes detection of glucose were sought using square-wave anodic stripping voltammetry (SW), with bismuth-immobilized carbon nanotube paste electrode (BCE). Methods: The optimum analytical results indicated sensitive peak signals on the BCE. The raw voltammogram was approached within the 1 mgL-1-14 mgL-1 and 10 ugL-1-140 ugL-1, detection limits with preconcentration times of 100 and 200 sec. Results: The relative standard deviation was 0.02 % (n = 15) of 10.0 mgL-1 under optimum conditions. The analytical detection limit (S/N) was attained at 8 ugL-1. The handmade microsensor was directly used in vivo on the living fish brain and human urine.Conclusion: The method was applied at real time in vivo, without requiring any pretreatment and other ionic electrolyte solutions. It can be used for medicinal and other materials requiring biological-fluid detection in real time. This study was designed to be suitable for real-time unmanned remote diagnosis and therapeutic drug injection into the body, micro-needle long-term administration, wearable artificial skin tattoo sensor, and real-time control. In addition, the glasses monitor was designed to be suitable for multitasking and multi-user control.

Leyla Mirhashimli, Afag Hasanova, A. Choriev

BIO Web of Conferences • 2025

The internationalization of the banking sector in developing countries brings both significant benefits and challenges. Foreign banks promote competition, efficiency and financial inclusion, which accelerates the integration of local banking systems into the global economy. However, the arrival of large international players may increase risks and force local banks to make significant changes. Studies show that the influence of foreign banks is ambiguous and depends on the level of economic development of the country. When assessing the effects of globalization, it is important to consider the differences between developed and developing countries. In periods of economic crisis, foreign banks can play a stabilizing role, but they can also import shocks from their own countries. To maximize benefits and minimize risks, it is necessary to develop a strategy that ensures a balanced presence of foreign banks, supports competition and innovation, but does not allow excessive concentration of bank capital. In this context, the internationalization of financial services becomes an important tool for strengthening and liberalizing the financial systems of developing countries, opening new opportunities for their economic growth and sustainable development. Since the collapse of the Bretton Woods system and the beginning of the era of financial liberalization, one of the most important manifestations of the process of integration of the banking sector into the world economy has been the expansion of foreign banking capital into foreign markets. Financial sector liberalization is intended to provide equal opportunities for financial institutions to access the international market or reduce restrictions from local regulators. Liberalization of the banking industry is one of the most important financial sector liberalization programs.

Dominique Larcher, Jennyfer Miot, Nadir Recham et al.

ECS Meeting Abstracts • 2014

Presently, the production of high-energy Li-ion based storage systems comes with large energy consumption and environmental impact, the most being the production of the electrode materials because of the high temperatures generally required and of the chemical nature of their components (transition metals). The main approaches explored to tackle this issue are i) finding new materials, enlisting alternative redox centers such as organics ii) exploring new synthetic ways using much lower temperatures iii) looking for efficient recycling processes. Living (i.e. aquatic) beings, owing to specific enzymatic-based metabolisms, are able to spontaneously trap, concentrate and transform soluble species, leading to precipitates (e.g. oxides, phosphates, carbonates …) with specific size, texture, morphology, at ambient temperature. In this study, we will exemplify the benefit of using bacteria to produce highly textured Fe-oxides and Fe-phosphates providing improved cyclability and power capability when reacted with lithium. Firstly, we report a method based on bacterial iron biomineralization for the synthesis of a-Fe 2 O 3 as conversion electrode material. This high-yield (> 80%) synthesis approach enlists (1) the room temperature formation of g-FeOOH via the use of the anaerobic Fe(II)-oxidizing bacteria Acidovorax sp . strain BoFeN1, and (2) the transformation of these BoFeN1 / g-FeOOH assemblies into an alveolar bacteria-free a-Fe 2 O 3 material by a short heat treatment under air. As the g-FeOOH precursor particles are preferentially precipitated between the two membranes of the bacteria cell wall (40-nm thick space), the final material consists of highly monodisperse nanometric (~ 40 x 15 nm) and oriented hematite crystals, assembled to form a hollow shell having the same size and shape as the initial bacteria (bacteriomorph) (Figure 1) . Besides X-Ray and electron diffraction studies, electrochemical galvonastatic signatures vs. Li (down to 0 Volt) confirm the formation of hematite (Figure 2, left) . However, the capacity retention of the bacteriomorph samples is found to be largely improved in comparison with samples which organization was prior destroyed by hand-milling while not altering the size/structure of the primary oxide grains (Figure 2, center) . In addition, long cycling tests enlightened a progressive in-situ loss of the bacteriomorph organization that correlates the observed long-term capacity decay. This original porous organization induced by the bacteria also positively impacts the power capability of the textured powder. Indeed, only 30% of the capacity is lost when cycling is performed from 1Li / 100 h to 1 Li / 6 min while the ground untextured powder is losing 85% of its initial and still low charge capacity (Figure 2, right) . Thanks to the dual textural control enabled by the bacteria (micrometric-level organization of nanometric primary grains), correlated enhanced reversibility and impressive high power capability could thus be achieved (J.Miot et al, Energy & Environmental Science 7(1), 451, 2014). Secondly, bacterially-induced eco-efficient and scalable room-temperature synthesis method can be applied to other systems, provided the bacteria strain is properly selected and adapted to the targeted material. For the room-temperature precipitation of Fe-based phosphates, Bacillus pasteurii was selected as its metabolism enlists urease enzyme controlling the decomposition of urea, thus the release ammonia in the medium, so finally its local pH. This allows the formation of nanometric and organized active grains (Figure 3) with specific assets towards Li-reactivity that will be also detailed.

Hidayati Istiqomah, Putri Anggun Puspitarini, Putty Ekadewi et al.

E3S Web of Conferences • 2018

One of the most promising areas with the existence of the lake is Universitas Indonesia. Universitas Indonesia (UI) has six lakes with a total area of 269,107 m 2 which is very important for its existence to balance the surrounding environment. Currently, the existence of UI lake has been contaminated with the COD value of about 1 to 8.000 mg/L due to a lot of garbage that enters and buried in it, that more attention is needed so that pollution will not increase. Microbial Desalination Cell (MDC) is a development system of Microbial Fuel Cell (MFC), which has the ability to desalinate seawater and can produce electricity by using microorganisms as waste decomposers. In addition, MDC method can also reduce the level of waste contained in the substrate used. To improve the performance of MDC, this study utilizes bio charcoal from rice husks to assess the performance of sodium percarbonate in the cathode chamber with a variation of 0.05 M concentration; 0.1 M; 0.15 M; and 0.2 M, and the performance of the addition of bacteria consortium on the substrate. The best results of this MDC study, in the variation of 0.15 M sodium percarbonate concentration with a decrease of COD and BOD of 93.98% and 87.67% and in variation of addition of bacteria consortium of 1 mL with decrease of COD and BOD 90.04% and 50.52%.

A.B. Safarov, O.I. Rakhmatov, Yu.G. Uzakova

BIO Web of Conferences • 2023

The article presents the results of research on the possibilities of providing heat-cooling and electricity supply systems to autonomous consumers located far from centralized energy supply in the southern regions of Uzbekistan (Bukhara and Kashkadarya) based on renewable energy sources. In these regions, the average daily relative solar energy is 4.5 kWh/m 2 /day, the average wind speed is 5.5...8.5 m/s, the relative energy is 300...580 W/m 2 , and the underground low-potential temperature at a depth of 3...5 m, on average, is +10...+12 o C. Analyzes of scientific research conducted on the development and reliability of trigeneration systems in the world are presented, and the possibilities of using these systems in our region are based. A combined solar-wind power plant, which is adapted to the climatic conditions of the southern regions of Uzbekistan, works efficiently in weak wind currents and high temperature regimes, and a complex energy system consisting of geothermal heat pumps that produce continuous heat and cold energy in different temperature regimes is offered. The proposed complex power plant allows for continuous and reliable energy supply to autonomous consumers located far from the centralized energy supply.

Ozcan Ozmen, John Zondlo, Shiwoo Lee et al.

ECS Meeting Abstracts • 2015

Nano-catalyst infiltration within porous Solid Oxide Fuel Cells (SOFC’s) electrodes is a well-known process to increase electrochemical performance. Conventional dripping methods usually require multiple infiltration steps in order to achieve optimum catalyst loading. In this study, an alternative process was developed to efficiently infiltrate nano-catalyst into the NiO/YSZ anode of an anode-supported commercial SOFC. Mussel inspired catechol-based adhesives were used as a surfactant layer within the 3-D electrode architecture to better control the infiltration kinetics and dispersion of the nano-catalyst. The work assessed the use of adhesive molecules, polymerized dopamine (PDA) and/or nor-epinephrine (PNE), as the bio-template layer for either metal oxide or hydroxide deposition. The bio-template adhesiveness on the pore walls was shown to provide higher nano-catalyst loading by avoiding segregation of the precipitate within the porous structure, which usually results in the migration and preferential deposition of the solute at the surface (during the drying process). The first objective was to better understand the templating kinetics of PDA and PNE with altering processing variables (eg. pH, solid loading, immersion time, etc.), in order to control nano-catalyst deposition amount. The second objective was to control the catalyst grain growth rate by manipulating the level of nano-catalyst percolation and by altering the composition of the catalyst to hinder diffusion and grain boundary mobility. The process started by first immersing the cell into the polymerized template solution up to 24 h and then immersed directly into the catalyst precursor solution, with the same protocol. Cerium oxide was used as a demonstration catalyst composition for this work, but later work will focus on other catalyst compositions. A dip-coating process for the entire cell was used for this work in order to evaluate the possibility of infiltrating both the anode and cathode at the same time. The final step included a singular firing to 750 o C to form CeO 2 catalyst. In that case, only one thermal firing step was needed to achieve high solids loading levels, which is unlike conventional dripping methods where multiple thermal steps are required. A correlation between ~300 hour cell performance and nano-catalyst characterization was developed by I-V-P testing and impedance spectroscopy at various duration during the constant current loading. In one heat cycle, dopamine assisted dip-coated cells reached 1.1 mg to 1.6 mg deposition of nano-ceria incorporation (for the combined anode and cathode). The most promising of the protocols included a) ex-situ polymerization, (where the biotemplate solution was polymerized in a separate beaker before infiltration) and b) in-situ polymerization (where the biotemplate solution was polymerized when the cell was in the bio-template medium). These methods showed an initial increase of the maximum power density at 750°C using humidifed H 2 fuel by ~20.7 and 17.9%, respectively. However, the grain growth of the nano-catalyst within the in-situ polymerized fuel cell caused a decrease in performance from 11.5% to 5.6 % in 300 h. Also, PNE assisted dip-coating protocol resulted in the deposition of 1.8 mg of nano-ceria by the same process. The cell showed ~13.6% higher increase in the maximum power density at ~24 h, but the cell degraded and the maximum power density decreased to ~2.1% lower than the baseline cell performance. Future work is focusing upon methods to control the nano-catalyst growth at the operating temperature. Methods of controlling the grain boundary migration rate using various solid-solution or secondary phase stabilization strategies are currently being investigated in order to achieve long-term stability of the infiltrated cells. Acknowledgements: As part of the National Energy Technology Laboratory’s Regional University Alliance (NETL-RUA), a collaborative initiative of the NETL, this technical effort was performed under the RES contract DE-FE0004000. This project was funded by the Department of Energy, National Energy Technology Laboratory, an agency of the United States Government, through a support contract with URS Energy & Construction, Inc. Neither the United States Government nor any agency thereof, nor any of their employees, nor URS Energy & Construction, Inc., nor any of their employees, makes any warranty, expressed or implied, or assumes any legal liability or responsibility for the accuracy, completeness, or usefulness of any information, apparatus, product, or process disclosed, or represents that its use would not infringe privately owned rights. Reference herein to any specific commercial product, process, or service by trade name, trademark, manufacturer, or otherwise, does not necessarily constitute or imply its endorsement, recommendation, or favoring by the United States Government or any agency thereof. The views and opinions of authors expressed herein do not necessarily state or reflect those of the United States Government or any agency thereof.

G. Qin, Y.C. Ding, Ya Xiong Liu et al.

Materials Science Forum • 2009

In the treatment of disorders, bio-electrodes are used to be implanted into the patients’ deep brain for long-term stimulation. This paper presents a custom design and flexible fabrication process of bio-electrode for treating neural disorders using rapid prototyping (RP) technique. A 3D model of the bio-electrode is designed and the photosensitive resin electrode prototype is fabricated on the laser rapid prototyping machine, and then the bio-electrode is fabricated using this electrode prototype and the silicon rubber mold and winding technique. The spatial distribution of the electric field fabricated of the bio-electrode is analyzed, and the optical photomicrograph reveals that the cylindrical surfaces of the polyurethane of the bio-electrode have smooth surface and no visible microcracks, and the spiral lines are arranged densely and have no defects of loose and falling and partly protruding. The electrochemical experiments show that the electrochemical process of the bio-electrode is reversible and the bio-electrode has good functionality and stability property.

, Nattakarn Wangfuengkanagul

• 2001

In this research, electrochemical analysis of drugs using a boron-doped diamond thin film electrode has been studied. Drugs, including acetaminophen, D-penicillamine and barbituric acid were investigated. The electrochemistry of drugs was studied by cyclic voltammetry. Comparison experiments were carried out using a polished glassy carbon (GC) electrode. At the diamond electrode, well-resolved cyclic voltammograms were obtained with current signal to background ratios higher than that obtained from the glassy carbon electrode. Detection limits of 10, 25 and 50 micrometre for acetaminophen, D-penicillamine and barbituric acid, respectively were obtained at the diamond electrode. Flow injection with amperometric detection using the diamond electrode was also studied. A significant low detection limit at 10 nM with signal to noise ratios higher than 3 and a linear range over 2-3 orders of magnitude were obtained. The purposed method was further applied to real drug samples in pharmaceutical preparations. These were paracetamol syrup and penicillamine capsule. The results obtained were satisfactory.

Jinpeng Liu, Harald Horn, Michael Wagner

• 2020

<p>Carbon-based and stainless steel-based materials are widely utilized as anode/cathode electrodes in bio electrochemical systems (BESs) due to its low capital cost, high conductivity and large specific surface area. Carbon-based materials such as carbon veil are mostly applied in lab-scale reactors because of its versatile shape and configuration. Moreover, stainless steel type materials show higher strength and are easier to incorporate within flow field. Optical coherence tomography (OCT) as an image technique is a suitable method to monitor biofilm growth and fluid-structure interactions at the meso-scale. In BESs, investigating bulk-biofilm interface (fluid-structure interactions) is of particular interest to optimize the mass transfer under suitable hydrodynamic condition and enhances the overall effectivity of BESs systems. To extend the knowledge about the influence of different anode electrodes as substratum on OCT monitoring and quantification, the biofilm structural properties analyzed by OCT image processing and bioelectrochemical systems performance were compared.  </p> <p>A custom-designed dual-chamber setup was constructed by two transparent optical flow cells and fixed in the automated monitoring platform (Evobot). Herein, we applied OCT to in-situ characterize and quantify the biofilm structure properties on two different anode electrodes (carbon veil-CV and porous stainless steel-SS) as substratum in microbial fuel cell (MFC) mode.  3D OCT dataset analysis presented 3 structural parameters for biofilm-carbon veil interface and 5 structural parameters for biofilm-stainless steel interface, separately. Biofilm volume (BioV) was calculated to compare CV and SS anode electrodes.</p> <p>In this study, a time-series of biofilm development was performed on both CV and SS materials. At the fourth day, the biofilm almost covered the entire anode surface and achieved 97% substratum coverage. Afterwards the biofilm grew mostly in vertical direction. With the further biofilm growth along height the electric resistance increased and power production gradually reached the equilibrium. Nevertheless, both materials did not show predominant advantage on power production. Furthermore, a relatively small error appeared on quantitative analysis of Biofilm volume using stainless steel. Whereas, the predictability of biofilm volume on the carbon veil anodes was hindered by the appearance of shadowing effects. Thus, it can be concluded that stainless steel flat plate electrode is preferable as anode material to investigate the interaction between biofilm structure, hydrodynamic conditions and mass transfer in BESs via OCT.</p>

Chonghui Yang

BIO Web of Conferences • 2023

Solar energy is the most abundant and clean energy on the earth, and developing equipment or devices with high-efficiency solar energy conversion is an effective way to alleviate the energy crisis. The majority of redox enzymes require a coenzyme to provide the hydrogen source needed for the reaction process, and the most commonly used coenzyme is nicotinamide adenine dinucleotide (NADH). However, NADH is expensive and easily decomposed, which greatly limits its application of artificial photosynthetic systems. We review recent progress in the construction of artificial photosynthetic systems that mimic natural photosynthesis.

Montadher M. Maktuf, Raed R. Shwaish, Shukry H. Aghdeab

BIO Web of Conferences • 2024

This study examined the material removal rate (MRR) affected by the variables of the electrochemical process including electrode type, voltage, electrolyte type, electrolyte concentration, and gap. Titanium alloy was employed as the workpiece, while copper was utilized as the cylindrical electrode. The input parameters were established according to Taguchi’s methodology. An analysis of variance (ANOVA) using a linear regression model was dependent on making sense of the experiment’s findings. the solid electrode achieved the maximum material removal rate (MRR) value (0.0857) g/min, while the hollow electrode with (1500 l/hour) flow rate achieved the minimum material removal rate (MRR) value (0.00002) g/min. the material removal rate (MRR) was directly proportional to the voltage. Maximum material removal rate (MRR) occurred at a concentration of (75 g/l) for the (NH 4 C) electrolyte, while minimum material removal rate (MRR) occurred at a concentration of (50 g/l) for the (NH 4 Cl) electrolyte. It has been observed that the contributing factors in controlling material removal rate (MRR) were as follows; (66.67%) for the voltage, (5.89%) for the electrode, (5.72%) for the electrolyte concentration, (3.24%) for the type of electrolyte, and (3.07%) for the gap.

Honglan Qi, Chengxiao Zhang

Luminescence • 2004

Abstract The electrogenerated chemiluminescence (ECL) reaction of lucigenin with isatin was investigated at a platinum electrode in a neutral aqueous solution. The ECL intensity of lucigenin at −0.65 V was greatly enhanced by isatin, and the ECL intensity was about 50 times higher than that of lucigenin without isatin. The enhanced ECL was believed to be produced by the chemiluminescence reaction between reduced lucigenin and superoxide anion that was generated by the reaction of electrochemically reduced isatin with dissolved oxygen. The conditions for the determination of isatin were optimized. Under the optimized condition, the enhanced ECL intensity vs. isatin concentration was linear in the range 4.8 × 10 −7 −1.9 × 10 −5 g/mL; with a detection limit of 3.3 × 10 −8 g/mL, and the relative standard derivation 1.0 × 10 −6 g/mL isatin was 3.8%. Copyright © 2004 John Wiley & Sons, Ltd.

Yin Song, Chunlei Wang

ECS Meeting Abstracts • 2014

There is urgent need to develop highly selective, sensitive and reproducible miniaturized bio-sensing platform based on reliable interface that is compatible with microfabrication processing. Our research objective is to advance fundamental research by fabricating pyrolyzed carbon arrays with high surface area as a bio-sensing electrode, developing the functionalization methods to increasing biomolecules immobilization efficiency and further understanding electrochemical phenomena occurring at bio/carbon interfaces. The carbon microelectrode arrays with high aspect ratio and porous surface have been fabricated by carbon microelectromechanical systems (C-MEMS) while the nanomaterials such as graphene have been integrated to further increase surface area. To achieve the efficient covalent immobilization of biomolecules, various oxidation and reduction functionalization methods have been investigated. The oxidation treatment we used in this study includes vacuum ultraviolet, electrochemical activation, UV/Ozone and oxygen RIE. The reduction treatment includes direct amination and diazonium grafting. The functionalized surface has been characterized using XPS, CV and FTIR to confirm and calculate the surface coverage of different functional groups. The developed bio-sensing platform was then applied for several applications, such as: DNA sensor; Glucose sensor; H 2 O 2 sensor; Aptamer sensor and HIV sensor. The performance and sensitivity of each biosensor will be discussed in the talk.

Qian Xiao

BIO Web of Conferences • 2023

With the aging of the population in China in recent years, the number of stroke patients is increasing day by day. The sequelae of stroke-induced foot drop are expected to regain some mobility after timely rehabilitation, but if patients do not receive early intervention, they may miss the best rehabilitation period and lose the ability to walk and stand completely. The traditional means of rehabilitation treatment is manual rehabilitation by rehabilitation physicians, but with the increase in the number of patients with movement disorders, the number of rehabilitation physicians has become significantly insufficient. The use of rehabilitation robots to provide adjunctive therapy to patients has become a common and effective means of rehabilitation worldwide. The early rehabilitation robots could only drive the patient to do passive rehabilitation and could not reflect the patient’s true motor intentions. Since EMG signals on the surface of the human body can advance the onset of human movement, they can be used to identify the intention of human movement. This paper validates and explores the experiment based on the underlying data.