Carlo Santoro, Sofia Babanova, Plamen Atanassov et al.

ECS Meeting Abstracts • 2014

Microbial fuel cell (MFC) is a bioelectrochemical capable of oxidizing organics compounds and generating electricity simultaneously. The ultimate goal would be to realize a low cost treatment system that would work in self-sustainable. In order to achieve that, our groups are moving towards materials study, characterization, modification and development and optimization with the vision of scaling up BES. Several sets of anodes carbonaceous and metallic materials have been investigated. Carbonaceous materials have been investigated and functionalized with chemical and electrochemical technique in order to increase oxygen and nitrogen functional groups that allow faster and higher bacteria attachment enhancing the biofilm electro-activity and electrons generation. Unfortunately, carbonaceous materials are very expensive and not enough robust to be deployed in long terms operation. As alternative, stainless steel (SS304) commercially available plain sheet has been investigated achieving similar performances compared to carbonaceous-based electrodes. The establishment of strictly anaerobic conditions in a short amount of time guaranteed also the conditions necessary to avoid metal corrosion. SS304 looks to be promising for large-scale applications due to the materials robustness and very reduced cost (order of magnitudes lower than carbonaceous-based groups). Further studies are currently in progress towards the direction of optimizing the SS304 material adding functional groups, hierarchically organized carbon structures and protecting the SS from long term possible deterioration and corrosion. Several sets of cathodes have been deployed also in order to replace the more expensive and utilized platinum and guarantee long terms conditions. Cathodes based on cheap and high surface area activated carbon has been deployed for treating wastewaters. Other efficient, highly active and low cost catalysts based on non-PGM catalysts have been also studied with high performances and actually better behavior of platinum in SCMFC due to the establishment of highly alkaline conditions in proximity of the cathode. Moreover, those catalysts showed a better resistance to get pollutants from toxic compounds naturally present into wastewater. The low cost, high performance and reduced possibility to get poisoned make non-PGM a suitable choice of catalysts to be deployed in BESs.

Irene S. Asetre, L. Tayo

2021 10th International Conference on Renewable Energy Research and Application (ICRERA) • 2021

Microbial fuel cell (MFC) systems are promising technologies that pose as an efficient alternative renewable energy source. This study evaluated the performance of MFCs inoculated with active soil microorganisms and fed with crab meat processing wastewater, using different proton exchange membranes and different electrode materials, in the production of bioelectricity and chemical oxygen demand (COD) reduction. MFC’s performance were analysed in terms of power density, energy output and COD reduction. COD concentrations were measured using standard Hach® COD kit Method 8000 with high range mercury vials. MFC reactors using titanium mesh wire electrodes demonstrated high open circuit potential (OCP) with peak values of 967 mV and 960 mV for MFC with Nafion membrane (MFC-Nafion) and MFC with gelatinised tapioca starch (MFC-GTS), respectively. Average power density output in closed circuit conditions peaked to as high as 9,908.52 mW/m3 for MFC-GTS reactor using carbon fiber brush electrodes. Energy plotted peaked at 235.88 J for MFC-GTS as a function of time calculated from geometric areal power density. COD reduction in MFC-GTS reactor was 31.05% and 36.06% using titanium wire mesh and carbon fiber brush electrodes, respectively. These results revealed that MFCs inoculated with active soil microbes using organic GTS membrane is a promising technology for bioenergy generation and COD reduction.

M. Then, S. Ramesh, M. Asrul et al.

IOP Conference Series: Materials Science and Engineering • 2021

Hydrogen has a great potential as an alternative energy and produces zero emissions, but most of hydrogen is produced from non-renewable fossil fuels via reforming. Thus, biomass is a promising replacement to fossil fuels where hydrogen can be sourced from. In this project, sago waste is chosen as raw material in a microbial electrolysis cell (MEC) to produce hydrogen fuel. A mathematical model with the integration of MEC with photo-fermentation has been developed and modified by using sago effluent as a substrate in a batch process. The main parameter such as concentration of microbial community has been observed in this project as it gives a huge influence on the gas product of MEC. In conclusion, the develop model was to observe the behavior of the microbial electrolysis cell where a maximum of 3.8 L/day (t = 4 days) of hydrogen production and 0.38A of MEC current were obtained.

A. Rosmalia, N. Dewi, I. Permana et al.

IOP Conference Series: Earth and Environmental Science • 2022

Asynchronous releasing rumen degradable protein (RDP) and energy reduces rumen microbial protein synthesis (MPS) and increases excess nutrients to the environment. Moreover, the ratio of RDP to rumen undegradable protein (RUP) was also important in improving the utilization of protein, especially for high-producing cows. However, the issue has not been a concern of most dairy concentrate manufacturers in tropical areas. The objective of this study was to determine the optimal ratio of RDP to RUP (RDUP) at different energy levels (TDN) of dairy cattle concentrate using in vitro method. The study used a 4 × 3 factorial randomized block design. The first factor was RDUP (1.50; 1.22; 1.00; 0.82) and the second factor was TDN levels (65%; 70%; 75%). Data were analyzed using ANOVA and followed by Duncan’s test. RDUP and TDN treatments affected NH3 concentration without interaction. Total VFA concentration, rumen bacteria, and protozoa population did not affect by the treatments. Dry matter and organic matter digestibility increased with increasing RDUP and TDN levels with an average of 71.58% and 70.67%, respectively. It is concluded that dairy concentrate based on RDP:RUP ratio at 1.50 (60:40) and 75% TDN improves fermentability and in vitro digestibility.

Attila Tókos, Monica Jipa, G. Cîrciumaru et al.

2022 International Conference on Electrical, Computer and Energy Technologies (ICECET) • 2022

In this paper, a system to stimulate in extremely low frequency (ELF) electric field the microbiological activity of the microbial flora in the active sludge of a wastewater treatment plant is presented. The designed and realized system was tested in industrial environment with and without ELF electric field stimulation. By comparing the two cases for the same degree of pollutants elimination from the wastewater, it resulted that the ELF electric field application significantly reduces the processing times in the biological treatment stages (to approximately half). Thus, the energy consumption in the biological treatment stage is reduced by approx. 50%, representing approx. 30% of the wastewater treatment plant energy consumption.

T. Luong, Stewart J. Thomas

Proceedings of the 20th ACM Conference on Embedded Networked Sensor Systems • 2022

With an ongoing search for alternative energy sources, plants may serve as a viable means for operating low-power digital circuits. Biopotential, the electrical signals found within the body due to electrochemical activity, can be monitored and harnessed within plants and vegetables. Measuring plant biopotential, in combination with electrogenic microbial fuel cell (MFC) technology [14], suggests that a self-sufficient and micro-power generation system can be made using a microbial fuel cell in tandem with a living plant [18]. This research presents ongoing work in proposed sub-systems within this power generation system and their compatibility with low-power electronics, a project inspired from works focused on converting plants into batteries [7, 8]. The power harvesting aspect of the project consists of long deployment experiments with mud based MFCs using MudWatt kits, as well as a plant based MFC. The plant sensing aspect of the project is depending on thigmonastic reactions from the plant specie Mimosa pudica.

Nan Xiao, Rong Wu, J. Huang et al.

2019 IEEE SENSORS • 2019

The rapid quantification of biological oxygen demand (BOD) plays an important role in monitoring water quality as well as its management in municipal wastewater treatment. Conventional methods based on consumption of dissolved oxygen over 5 days are slow, labor-intensive and usually require skilled personnel and a well-equipped laboratory. Microbial fuel cells (MFCs) have the ability to convert energy from the chemical form to electrical form and could be used directly measure BOD in an automated way. Nevertheless, these transducers are large, expensive and have a relatively long response time which limits their application as BOD sensors. Here, we use xurographic fabrication technology to rapidly fabricate a low cost micro-MFC and demonstrate its suitability to measure BOD. The miniaturized sensor was fabricated in 10 min, with small reaction volume of only 1.8 µL resulting in a faster response time of only 1.1 min and a larger detection range of 18492 mg/L BOD. These findings demonstrate that the use of xurographic methods to fabricate MFCs can enable low cost measurement of BOD in a rapid manner. These sensors have potential for application in wastewater treatment plants for both monitoring as well as control.

P. Serra, A. Espírito-Santo, A. Albuquerque

2015 IEEE International Conference on Industrial Technology (ICIT) • 2015

The improvement of methods to harvest the energy produced by a Microbial Fuel Cells is receiving growing attention from the scientific community. The motive is related with the possibility to join the wastewater treatment process with the production of energy. This last process is strongly dependent from several biochemical parameters that can affect the energetic efficiency of the MFC. The experimental setup here proposed allows the correlation of MFC's operating conditions with the energetic productivity. The mechanisms that manage the mode how energy is extracted from the cell can be improved based on the experimental information obtained from the proposed setup.

Ghaibulna Abdol Lajis, J. Jasni, Mohd Faizuddin Kamaruddin et al.

2022 IEEE International Conference on Power and Energy (PECon) • 2022

Sustainability has been one of the most important topics discussed lately-part of sustain ability strategies focusing on global warming and food security issues. Alternative energy sources of various kinds have been explored and applied to mitigate the impact of fossil fuels in the last decade. The electricity generation from living plants has evolved as a new alternative renewable energy source known as a plant microbial fuel cell (PMFC). This paper investigated the bioelectricity generation in economic crops at aquaponics systems using PMFC. The result reveals that economic crops could generate bioelectricity using the PMFC. In the experiment, a single-chamber PMFC configuration was conducted on two economic crops, chilli and okra, with graphite felt as an electrode. As a result, chilli generated 19.58 nW while okra generated 17.00 n W, where chilli outperformed the okra in terms of power generation.

J. Prasad, R. K. Tripathi

2018 2nd IEEE International Conference on Power Electronics, Intelligent Control and Energy Systems (ICPEICES) • 2018

This paper presents sediment microbial fuel cell (SMFC) and a Dc-Dc boost converter. In which, an SMFC generates a maximum voltage of 1.16V, which is not sufficient to drive the low power electronic device. Therefore, a self-sustainable Dc-Dc boost converter is designed to boost up the SMFC voltage from 1.161V to 3.289V. This is simulated in the LTspice software by using an LTC3108 integrated circuit (IC). The performance of this proposed boost converter is analyzed at different load resistance. During the analysis, we found that output voltage and current of the boost converter are almost constant when the load resistance made equal to the internal resistance of the SMFC. The energy harvester Dc-Dc boost converter can deliver upto 3.289V, which is sufficient to power sensor devices, remote water sensing and other remote broadcasts etc. The proposed Dc-Dc boost converter is self-sustainable because it is powered entirely from harvested energy without requiring extra external power sources.

M. Shahparasti, J. Rocabert, R. Muñoz et al.

2018 7th International Conference on Renewable Energy Research and Applications (ICRERA) • 2018

In this paper, a new type of single-stage interlinking converters for Microbial Electrosynthesis (MES) energy storage applications connected to the three-phase grid is presented, in which impedance source network (ZSN) is employed to reduce cost and volume, and meanwhile improve the efficiency. Impedance source converter (ISC) with buck-boost characteristic is able to feed MES with a wide range of voltages in DC side, also, converter grid distortion in AC side is reduced because there is no need to dead time for switching. Different ZSNs are studied and discussed for MES energy application. The applicable ones are selected and a comprehensive comparison is presented. Also, the proposed efficient control for ISC consists of two parts, first ZSN capacitor control plus reactive power control are done by controlling modulation index, and second the objective of tracking active power reference can be achieved by means of controlling shoot-through duty cycle. Simulation results are presented to certify the comparison between ZSNs and to verify the merit of the proposed control scheme.

E. M. Putri, M. Zain, L. Warly et al.

IOP Conference Series: Earth and Environmental Science • 2024

The traditional approach to feeding ruminant is based on the needs of protein and energy to enhance production and productivity. It is crucial to note the protein degradability in feed as microbial rumen needs ammonia from rumen degradable protein (RDP), while ruminant needs bypass protein also known as rumen undegradable protein (RUP) alongside microbial crude protein. Through the use of an in vitro technique, the recent study aimed to determine the optimal level of protein, energy, and RDP:RUP ratio in the diet of beef cattle by observing VFA partial production, protozoa population, and methane gas emissions. Various dietary treatments were formulated (based on dry matter content) comprised three protein levels (12%, 14%, and 16%), two energy levels (65% and 70%), and three RDP:RUP ratio levels(55:45 for low RDP, 60:40 for medium RDP, and 65:35 for high RDP). The study followed 3x3x2 factorial randomized block design with three replications. The dietary treatments were incubated with buffered rumen fluid. This study showed acetic, propionic, and butyric acid production were influenced by protein, energy, RD:RUP ratio (P<0.05). Meanwhile, protozoa population and methane gas emission were reduce by dietary protein, energy, and RDP:RUP ratio. In summary, dietary protein, energy, and RDP:RUP ratio impacts the production of VFA, protozoa population, and methane gas emissions. The diet comprising 14% dietary protein, 70% energy, and 60%:40% of RDP: RUP optimizes the production of VFA, while simultaneously reducing protozoa population and methane gas emissions.

P. Serra, A. Espírito-Santo, M. Magrinho

IECON 2018 - 44th Annual Conference of the IEEE Industrial Electronics Society • 2018

The water-energy nexus plays a significant role on society and on the industrial panorama. Creating a network of self-powered smart sensors for quality evaluation on wastewater treatment stations would allow for major automation of this process while decreasing its energy dependence. Current technology allows energy harvesting from wastewater with Microbial Fuel Cells. This work reports on the construction and evaluation of a single-chamber air-cathode microbial fuel cell for power production. Around 900 mW.m−2 of power was retrieved from this source and used on a low power energy harvesting kit after leveled up on a voltage booster. The sensing system is developed around a low power microcontroller.

M. Baharuddin, Heri Heriyono, S. Wali et al.

Proceedings of the 1st International Conference on Science and Technology, ICOST 2019, 2-3 May, Makassar, Indonesia • 2019

Microbial Fuel Cell (MFC) was a Technology that produced electrical energy utilizing microorganism. The purpose of this study was to know enceng gondok potency as substrate in MFC system and add electrolyte solution and buffer. This study used enceng gondok as substrate and Pseudomonas sp. bacteria. The Method of this study was using double compartment that consist of anode and cathode chambers. Both of them were related by salt bridge. The result showed that electric current and potential differences maximum that was produced (without added of electrolyte solution and buffer) was 0.11 mA and 0,27 V while power density was 20.34 mW/m2. Whereas Electrolyte solution and buffer combination showed electric current and potential differences maximum that produced was 3.06 mA and 0.86 V while power density yaitu 1802.46 mW/m2.

V. Umasankar, Danyaa Manjai V Mohan, V. kalaivanan et al.

IOP Conference Series: Materials Science and Engineering • 2020

Microbial fuel cell is one of the emerging technologies which utilize wastewater to generate electricity with the help of action of microorganisms. The real interest in microbial fuel cells has tremendously grown in recent years. It converts chemical reaction into electrical energy and helps in the recovery of energy from wastewater. The main objective of this study was to enhance the electricity production and simultaneously treat the wastewater. The lab scale model consists of double chamber microbial fuel cell, i.e., two separate chambers one with salt water and the other with wastewater representing anode and cathode, a salt bridge acting as proton exchange membrane; electrodes from batteries are used for this study. In this, the proton exchange and electron transfer occurs after the redox reaction. The microbes in the sludge or wastewater are responsible for the release of electrons. These electrons tend to move through the external circuit, producing electricity. For maintaining electrical neutrality salt bridge is used. The dual chamber microbial fuel cell used in this experiment produced an average voltage of 0.37mv for a wastewater volume of one liter. This set up is done on small scale, but with further and more detailed study it can be installed in industries that produce Microbial Waste water as a by-product to generate electricity and reuse the waste water for other processes after treatment.

N. Emalya, E. Munawar, S. Suhendrayatna et al.

IOP Conference Series: Earth and Environmental Science • 2021

In developing countries, the presence of wastewater is undesirable due to a costly investment for the treatment unit and energy-intensive for the operation. The wastewater treatment units in developing countries usually are not appropriately operated due to lacking operational cost. Therefore, it is not surprising if wastewater has never been considered a potential resource, even though it is rich in organics and nutrient substances. Biological treatment enables the conversion of wastewater into valuable products and energy. Sediment Microbial fuel cells (SMFCs) are emerging technologies envisaged as a feasible solution for simultaneous removal of carbonaceous compounds and generation of electricity. In SMFCs, power can be generated naturally by embedding an anode in the sediment and immersing the cathode in the water above the sediment. One of the most significant obstacles to upscaling and practical applications of the SMFCs appears to be the low-power output. The entire performance of an SMFC is determined by microorganisms, proper electrode materials, optimal SMFC designs, and process parameter optimization. This paper will discuss the recent progress of SMFC research related to its application in wastewater treatments and energy production. The advantages and obstacles of using SMFC in wastewater treatment are also presented.

P. Sivasankar, Suresh Kumar Govindarajan

SPE Asia Pacific Enhanced Oil Recovery Conference • 2015

The present work numerically investigates the effect of reservoir temperature and pH on microbial growth and its transport within the reservoir which undergoes the reversible sorption kinetics. Further, the present work also studies the influence of reservoir temperature and pH on changes in interfacial tension between oil and water, capillary pressure and its impact on microscopic oil displacement efficiency. The microbe used is strain of Bacillus sp and the nutrient supplied to microbe is molasses. For this purpose, a novel mathematical model is developed which describes the coupled multiphase fluid flow and multispecies reactive transport in porous media which occurs during the MEOR process. Moreover, in the present work, the first order Monod kinetics equation is expressed as a function of temperature and pH which dictates the microbial growth rate. The developed mathematical model is sloved numerically by finite volume discretization technique and the results are found to be numerically stable and validated with the experimental results. The numerical data used for validation and for numerical simulation studies are presented. The results suggest that the oil displacement efficiency increases as the reservoir temperature and pH approaches the optimum temperature and pH required for microbes to reach its maximum growth. The present numerical model may be applied as an effective screening tool before the application of MEOR process and also serves as a reservoir simulator tool to predict the performance of MEOR process.

Daehyun D. Kim, Corynne O'Farrell, Courtney R. A. Toth et al.

Microbial Biotechnology • 2018

Summary As a preliminary investigation for the development of microbial‐enhanced oil recovery strategies for high‐temperature oil reservoirs (~70 to 90°C), we have investigated the indigenous microbial community compositions of produced waters from five different high‐temperature oil reservoirs near Segno, Texas, U.S. (~80 to 85°C) and Crossfield, Alberta, Canada (~75°C). The DNA extracted from these low‐biomass‐produced water samples were analysed with MiSeq amplicon sequencing of partial 16S rRNA genes. These sequences were analysed along with additional sequence data sets available from existing databases. Despite the geographical distance and difference in the physicochemical properties, the microbial compositions of the Segno and Crossfield produced waters exhibited unexpectedly high similarity, as indicated by the results of beta diversity analyses. The major operational taxonomic units included acetoclastic and hydrogenotrophic methanogens ( Methanosaetaceae , Methanobacterium and Methanoculleus ), as well as bacteria belonging to the families Clostridiaceae and Thermotogaceae , which have been recognized to include thermophilic, thermotolerant, and/or spore‐forming subtaxa. The sequence data retrieved from the databases exhibited different clustering patterns, as the communities from close geographical locations invariably had low beta diversity and the physicochemical properties and conditions of the reservoirs apparently did not have a substantial role in shaping of microbial communities.

Nuria Fernandez-Gonzalez, Julie A. Huber, Joseph J. Vallino

bioRxiv (Cold Spring Harbor Laboratory) • 2016

Abstract Although microbial systems are well-suited for studying concepts in ecological theory, little is known about how microbial communities respond to long-term periodic perturbations beyond diel oscillations. Taking advantage of an ongoing microcosm experiment, we studied how methanotrophic microbial communities adapted to disturbances in energy input over a 20 day cycle period. Sequencing of bacterial 16S rRNA genes together with quantification of microbial abundance and ecosystem function was used to explore the long-term dynamics (510 days) of methanotrophic communities under continuous versus cyclic chemical energy supply. We observed that microbial communities appear inherently well-adapted to disturbances in energy input and that changes in community structure in both treatments are more dependent on internal dynamics than on external forcing. Results also show that the rare biosphere is critical to seeding the internal community dynamics, perhaps due to cross-feeding or other strategies. We conclude that in our experimental system, endogenous feedbacks were more important than exogenous drivers in shaping the community dynamics over time, suggesting that ecosystems can maintain their function despite inherently unstable community dynamics. IMPORTANCE Within the broader ecological context, biological communities are often viewed as stable and only experience succession or replacement when subject to external perturbations, such as changes in food availability or introduction of exotic species. Our findings indicate that microbial communities can exhibit strong internal dynamics that may be more important in shaping community succession than external drivers. Dynamic ”unstable” communities may be important for ecosystem functional stability, with rare organisms playing an important role in community restructuring. Understanding the mechanisms responsible for internal community dynamics will certainly be required for understanding and manipulating microbiomes in both host-associated and natural ecosystems.

Juan L. Ramos, Ben Pakuts, Patricia Godoy et al.

Microbial Biotechnology • 2022

Summary Much of the energy being used to power our lives comes from fossil fuels such as coal, natural gas and petroleum. These energy sources are non‐renewable, are being exhausted and also pollute the air, water and soil with toxic chemicals. Their mining, transportation, refining and use are associated with a large carbon footprint that contributes significantly to global warming. In addition, the geopolitical complexities surrounding the main fossil fuel producers create risks and uncertainties around the world. Replacing fossil fuels with clean, renewable forms of energy is paramount to creating a sustainable and healthy future, and for laying the foundations for global political stability and prosperity. Using biomass from plants, microbes can produce biofuels that are identical to or perform as well as fossil fuels. In addition of creating sustainable energy, advancing the biofuel industry will create new, high‐quality rural jobs whilst improving energy security.

Nobuyuki Horinouchi, Takafumi Sakai, Takako Kawano et al.

Microbial Cell Factories • 2012

Abstract Background Reproduction and sustainability are important for future society, and bioprocesses are one technology that can be used to realize these concepts. However, there is still limited variation in bioprocesses and there are several challenges, especially in the operation of energy-requiring bioprocesses. As an example of a microbial platform for an energy-requiring bioprocess, we established a process that efficiently and enzymatically synthesizes 2′-deoxyribonucleoside from glucose, acetaldehyde, and a nucleobase. This method consists of the coupling reactions of the reversible nucleoside degradation pathway and energy generation through the yeast glycolytic pathway. Results Using E. coli that co-express deoxyriboaldolase and phosphopentomutase, a high amount of 2′-deoxyribonucleoside was produced with efficient energy transfer under phosphate-limiting reaction conditions. Keeping the nucleobase concentration low and the mixture at a low reaction temperature increased the yield of 2′-deoxyribonucleoside relative to the amount of added nucleobase, indicating that energy was efficiently generated from glucose via the yeast glycolytic pathway under these reaction conditions. Using a one-pot reaction in which small amounts of adenine, adenosine, and acetone-dried yeast were fed into the reaction, 75 mM of 2′-deoxyinosine, the deaminated product of 2′-deoxyadenosine, was produced from glucose (600 mM), acetaldehyde (250 mM), adenine (70 mM), and adenosine (20 mM) with a high yield relative to the total base moiety input (83%). Moreover, a variety of natural dNSs were further synthesized by introducing a base-exchange reaction into the process. Conclusion A critical common issue in energy-requiring bioprocess is fine control of phosphate concentration. We tried to resolve this problem, and provide the convenient recipe for establishment of energy-requiring bioprocesses. It is anticipated that the commercial demand for dNSs, which are primary metabolites that accumulate at very low levels in the metabolic pool, will grow. The development of an efficient production method for these compounds will have a great impact in both fields of applied microbiology and industry and will also serve as a good example of a microbial platform for energy-requiring bioprocesses.

Uwe Schröder, Falk Harnisch, Largus T. Angenent

Energy &amp; Environmental Science • 2015

This paper provides a scaffold for the development of a clear and consistent terminology and classification of microbial electrochemistry and microbial electrochemical technologies.

Sara Tejedor‐Sanz, Young Eun Song, Eric R. Sundstrom

Microbial Biotechnology • 2024

Abstract The exploration of novel hosts with the ability to assimilate formic acid, a C1 substrate that can be produced from renewable electrons and CO 2 , is of great relevance for developing novel and sustainable biomanufacturing platforms. Formatotrophs can use formic acid or formate as a carbon and/or reducing power source. Formatotrophy has typically been studied in neutrophilic microorganisms because formic acid toxicity increases in acidic environments below the pKa of 3.75 (25°C). Because of this toxicity challenge, utilization of formic acid as either a carbon or energy source has been largely unexplored in thermoacidophiles, species that possess the ability to produce a variety of metabolites and enzymes of high biotechnological relevance. Here we investigate the capacity of several thermoacidophilic archaea species from the Sulfolobales order to tolerate and metabolize formic acid. Metallosphaera prunae, Sulfolobus metallicus and Sulfolobus acidocaldarium were found to metabolize and grow with 1–2 mM of formic acid in batch cultivations. Formic acid was co‐utilized by this species alongside physiological electron donors, including ferrous iron. To enhance formic acid utilization while maintaining aqueous concentrations below the toxicity threshold, we developed a bioreactor culturing method based on a sequential formic acid feeding strategy. By dosing small amounts of formic acid sequentially and feeding H 2 as co‐substrate, M. prunae could utilize a total of 16.3 mM of formic acid and grow to higher cell densities than when H 2 was supplied as a sole electron donor. These results demonstrate the viability of culturing thermoacidophilic species with formic acid as an auxiliary substrate in bioreactors to obtain higher cell densities than those yielded by conventional autotrophic conditions. Our work underscores the significance of formic acid metabolism in extreme habitats and holds promise for biotechnological applications in the realm of sustainable energy production and environmental remediation.

Pauline L. Folch, Markus M.M. Bisschops, Ruud A. Weusthuis

Microbial Biotechnology • 2021

Summary Microbial production of bulk chemicals and biofuels from carbohydrates competes with low‐cost fossil‐based production. To limit production costs, high titres, productivities and especially high yields are required. This necessitates metabolic networks involved in product formation to be redox‐neutral and conserve metabolic energy to sustain growth and maintenance. Here, we review the mechanisms available to conserve energy and to prevent unnecessary energy expenditure. First, an overview of ATP production in existing sugar‐based fermentation processes is presented. Substrate‐level phosphorylation (SLP) and the involved kinase reactions are described. Based on the thermodynamics of these reactions, we explore whether other kinase‐catalysed reactions can be applied for SLP. Generation of ion‐motive force is another means to conserve metabolic energy. We provide examples how its generation is supported by carbon‐carbon double bond reduction, decarboxylation and electron transfer between redox cofactors. In a wider perspective, the relationship between redox potential and energy conservation is discussed. We describe how the energy input required for coenzyme A (CoA) and CO 2 binding can be reduced by applying CoA‐transferases and transcarboxylases. The transport of sugars and fermentation products may require metabolic energy input, but alternative transport systems can be used to minimize this. Finally, we show that energy contained in glycosidic bonds and the phosphate‐phosphate bond of pyrophosphate can be conserved. This review can be used as a reference to design energetically efficient microbial cell factories and enhance product yield.

Ting Ge, Chen Yang, Bo Li et al.

BMC Veterinary Research • 2023

Abstract Higher dietary energy is often used to achieve better animal performance in mutton sheep production. Notably, changing the diet formula affects rumen fermentation and the microbiota of ruminants. In this study, we investigated the effect of dietary energy on rumen fermentation and ruminal microbiota in fattening sheep. Fifteen 2-month-old white-headed Suffolk sheep (♂) × Hu sheep (♀) crossbred lambs were randomly divided into three treatments based on the dietary energy of the feeds fed: 8.67 MJ/kg (Low energy (LE); n = 5), 10.38 MJ/kg (standard energy (CON); n = 5), and 12.31 MJ/kg (high energy (HE); n = 5) groups. After 70 days of feeding, sheep were slaughtered and the ruminal fluids were collected and analyzed to determine fermentation parameters. Microbiota was determined using metagenomics sequencing. Notably, the microbial cell protein (MCP) and butyric acid concentrations were significantly high in the HE group. Metagenomic sequencing revealed that ACE and Chao indexes of the HE group were significantly decreased. Four genera among the major classified taxa across all the kingdoms differed in relative abundance in the three dietary energy levels. The relative abundances of Prevotella_brevis, Succiniclasticum_ruminis, Prevotellace-ae_bacterium, and Lachnospiraceae_bacterium were significantly correlated with rumen fermentation. Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analysis further revealed that a high-energy diet increased lipid metabolism of microbiota. The Carbohydrate Active enzymes (CAZy) gene, which participates in energy metabolism, was upregulated, while genes regulating plant cell wall degradation were downregulated in the HE group. These results suggest that a high-energy diet had minimal influence on the rumen fermentation pattern but altered the composition of the rumen microbiota, enhancing microbial lipid metabolism and limiting crude fiber metabolism. The findings of this study provide scientific evidence of the effect of dietary energy on ruminant fermentation and fattening sheep production.

Richard J. Johnson

SPE International Conference on Oilfield Chemistry • 2017

Abstract Microorganisms can cause numerous issues in oil field systems, including microbiologically influenced corrosion (MIC), reservoir souring, biofouling and separation problems. They are often controlled using biocides, however the dynamic nature of both oil field systems and microbial communities means that this is not a set up and leave solution. Therefore, rigorous biocide selection and microbial monitoring must be carried out in tandem to ensure that the treatment chemicals are effective from both a technical and cost point of view. Microbial monitoring has advanced significantly in recent years, and now incorporates molecular DNA techniques such as quantitative polymerase chain reaction (qPCR) to quantify microorganisms, and metagenomics to identify them. These data however, still need relating back to the methods used to control microbial proliferation in oil field systems. In this paper a combined approach is presented, with use of an onsite biocide evaluation test apparatus (BETA) to test up to sixteen biocides simultaneously at different dose rates and contact times for many repeated dosages. This is connected to a production or water injection system to realistically simulate pipeline conditions (e.g. temperature, pressure, flow rate, water chemistry, surface materials, etc.) during biocide evaluation. This allows for biocides to be techno-economically ranked under process conditions and may also be used to determine the effects of different biocide regimes on corrosion and pitting rates. Any changes to the microbial community are detected early using the latest molecular microbiology techniques to ensure that the biocide maintains its effectiveness. This guarantees that any required biocide re-evaluation is carried out when needed, meaning that ineffective biocides are not needlessly dosed, which would increase operating expenditure (OPEX) costs and risks to asset integrity. It also avoids needless biocide re-evaluations where the current regime is working effectively. An understanding of the type of data from different microbial monitoring tools is important and interpreting this correctly helps to bring a combined approach together, with some of the common pitfalls discussed. By using the most appropriate tools in the microbiologist's tool box for routine monitoring, along with a rigorous biocide evaluation regime, these advances can be used to keep a close control on OPEX along with improving asset integrity and increasing production.

Jeremy F. Chignell, Hong Liu

ASME 2011 International Manufacturing Science and Engineering Conference, Volume 1 • 2011

The manufacture of biodiesel generates 10 wt% of glycerol as a byproduct. Currently, the majority of this waste glycerol is treated in wastewater treatment plants or incinerated. In this study, single chamber, membrane-free microbial electrolysis cells (MECs) was evaluated to produce hydrogen from pure glycerol and waste glycerol. At an applied voltage of 0.6 V, a maximum current density of 7.5 ± 0.4 A/m2 (238.6 ± 12.7 A/m3) was observed, the highest reported current density for a microbial electrochemical system operating on glycerol. Maximum current densities on 0.5% waste glycerin were 0.1–0.2 A/m2, much lower than those on pure glycerol, possibly due to the high salt and soap concentration in the waste glycerol. The maximum hydrogen yield on 50 mM glycerol was 1.8 ± 0.1 mol hydrogen/mol glycerol at a hydrogen production rate of 1.3 ± 0.1 m3/day/m3. The presence of methanol in the waste glycerin reduced hydrogen yield by nearly 30%. The energy efficiency on 0.5% of waste glycerol reached 200% at an applied voltage of 0.6 V. Conversion of all of the waste glycerol currently generated annually in global biodiesel manufacture to hydrogen using optimized MEC technology could generate ∼ 180 million kg of H2, representing a value of nearly $540 million, or the amount of H2 required for the production of 4.8 billion kg of green diesel. This study indicates that the generation of useful products (such as hydrogen) from waste glycerol will greatly increase the viability of the growing biodiesel industry.

P. Hosseininoosheri, H. Lashgari, K. Sepehrnoori

SPE Trinidad and Tobago Section Energy Resources Conference • 2016

Abstract Capillary force limits the efficiency of water flooding by trapping the oil in porous media. High capillarity is caused by high interfacial tension (IFT) between oil and water that leads to a high residual oil saturation. Surfactants are widely used to reduce IFT and significantly mobilize the entrapped oil. However, the surfactants that are injected into a reservoir to lower the IFT several orders of magnitude may not be cost effective. A cost effective alternative for surfactant flooding is microbial enhanced oil recovery (MEOR). In the MEOR process, nutrients and natural bacteria are injected into a reservoir and both indigenous and injected microorganisms are able to react and then generate biosurfactants based on in-situ reactions. Modeling a microbial enhanced oil recovery process requires coupling kinetics transport with local equilibrium transport in the presence of the surfactant phase behavior model (i.e. Hand's rule). In general, reservoir simulators do not model relative chemical reactions that consider the effect of essential environmental parameters such as temperature, salinity, and pH. The main objective of this work is to present first order Monod kinetic equations as a function of temperature, salinity, and pH, which control the biodegradation reactions and microbial growth rate. This involves investigating the impact of biosurfactant adsorption, maximum growth rate, and nutrient concentration. Next, the effects of environmental factors are implemented in a four-phase chemical flooding reservoir simulator (UTCHEM). Finally, the simulator is used to history match coreflood experimental data to model the contribution of the cited parameters on oil recovery. Results show that in-situ biosurfactant generation rates can be thoroughly modeled based on environmental factors and IFT can be reduced in a similar manner as surfactants. Simulation results show 10-15% incremental oil recovery using in-situ biosurfactant compared to waterflooding. The simulation results show that nutrient concentration, salinity and temperature are the most significant parameters influencing oil recovery, whereas pH has an insignificant effect. The key findings of this work are the following: In-situ biosurfactant generation in a MEOR process is mathematically described.A new environmental model is implemented into the simulator.Various parameters influencing the efficiency of the MEOR process are investigated.

Dara Nyknahad, W. Bein, L. Gewali et al.

2021 IEEE 11th Annual Computing and Communication Workshop and Conference (CCWC) • 2021

In this paper, we study the grid scheduling problem in a battery exchange station (BES) as a part of the battery consolidation system (BCS). We define the grid scheduling problem as the BES's service scheduling to exchange batteries of electric vehicles (EVs), the battery exchange price scheduling, and the electricity buying scheduling for a day ahead. We mathematically formulate the problem as a multi-objective optimization problem which aims at maximizing the BES's income and EVs' satisfaction, subject to the constraints of servicing all EVs arrived in the BES during a day, the limitation on the amount of buying electricity, and the limitation on the available full batteries at the beginning of the day. The stated problem is non-convex. To construct a convex problem, we apply the McCormick envelopes method. Subsequently, we solve the problem by CVX. Our simulation outcomes show that the BES can efficiently schedule the service, the battery exchange price, and the electricity buying based on the electricity price and the EVs' arrival distributions for a day ahead by applying our proposed method.

P. Goncharov, D. Rusov, Anastasiia Nikolskaia et al.

Proceedings of The 6th International Workshop on Deep Learning in Computational Physics — PoS(DLCP2022) • 2022

Particle tracking is an essential part of any high-energy physics experiment. Well-known tracking algorithms based on the Kalman filter are not scaling well with the amounts of data being produced in modern experiments. In our work we present a particle tracking approach based on deep neural networks for the BM@N experiment and future SPD experiment. We have already applied similar approaches for BM@N RUN 6 and BES-III Monte-Carlo simulation data. This work is the next step in our ongoing study of tracking with the help of machine learning. Revised algorithms - combination of Recurrent Neural Network (RNN) and Graph Neural Network (GNN) for the BM@N RUN 7 Monte-Carlo simulation data, and GNN for the preliminary SPD Monte-Carlo simulation data are presented. Results of the track efficiency and processing speed for both experiments are demonstrated.

Jianjun Liu, Xianghua Chen, H. Zuo et al.

2020 15th Symposium on Piezoelectrcity, Acoustic Waves and Device Applications (SPAWDA) • 2021

Electrical power can be harvested from the ambient vibrations using piezoelectric materials. The Macro Fiber Composite (MFC) constructed employing piezoelectric fibers embedded in an epoxy matrix and coated with plyimide skin can offer strongly flexibility, excellent performance of electronics and high efficiency of energy capture. This is the excellent match for vibration energy harvesting, which make it well suited for low-power active device continuously. In this paper an innovative energy harvestor system is desigen adopt the MFC from the high altitude stable wind vibration source. Numerical model are simulated via the finite element analysis. The influence of the material parameters of the flexible matrix of MFC on the vibration energy harvesting is further studied and analyzed in this paper. The research shows that the MFC achieved a maximum output power of $13.5\mu \mathrm{W}$ with suitable flexible matrix material at the specific wind load $15\mathrm{m}/\mathrm{s}$. The advantages of energy harvesting using MFC and its potential applications in low power electronics and wireless sensors make a bright future in the aerospace industry.

X. Liu, X. Liu, Y. Zhao

IET Conference Proceedings • 2021

Metallized film capacitor is widely used in pulse power generators and HVDC power transmission system. The high reliability of capacitor is mainly beneficial from the self-healing process. With the increase of its operation time and discharge time, frequent self-healing leads to loss of capacitance. Therefore, it is important to develop an effective detection method to monitor the self-healing characteristics of MFC. In this paper, a self-healing detection method based on acoustic and electric combination is proposed for MFC with high sheet resistance and the self-healing ultrasonic signal is analyzed. The influence of pulsed discharge times on the characteristic of self-healing is studied through online self-healing detection method. The results show that peak frequency of ultrasonic signal is between 50 kHz and 60 kHz. As the number of pulsed discharge time increases, low voltage self-healing discharges become more frequent and the self-healing frequency has same increasing trend with capacitance loss. When the capacitor is near the end of its life, the self-healing frequency increases sharply and the probability of high-energy self-healing point increases significantly. It's indicated that this detection method has a good application prospect for the monitor of aging state of the capacitor through the change of the self-healing characteristic.

Jia-qi Chen, Y. Hao, W. Zhang

2020 15th Symposium on Piezoelectrcity, Acoustic Waves and Device Applications (SPAWDA) • 2021

The bistable composite laminates are kind of structural unit with two stable equilibrium states. Due to the complexity of mathematics, the mechanical analysis of trapezoidal plates is seldom studied, which can provide theoretical basis for the development of deformable intelligent structures such as collapsible structures, deformable wings and energy concentrators, though. Based on the classical theory, a new model of trapezoidal cross-laminated bistable laminates is presented in this paper. Using the principle of minimum potential energy, Newton-Raphson technique and the application of higher order polynomials in the configuration function, two steady state configurations of trapezoidal laminated plates with different geometrical sizes under free boundary conditions are studied. In addition, flexible intelligent piezoelectric microfiber composite (MFC) actuators are used to trigger the snap-through between two stable configurations of bistable laminates. The voltage required to drive the change of bistable structure of trapezoidal laminates is calculated. The calculation of the bistable model has a certain guiding significance for the design and manufacture of equipment and mechanism under various special circumstances.

Feng Liu, Xue-song Ye, Tao Wu et al.

Sensors • 2008

A critical issue in bioelectrochemical applications that use electrodes modified by Single Wall Carbon Nanotubes (SWCNTs) is to ensure high activity of the catalytic site of an immobilized enzyme protein interacting with nanomaterials. Since Flavin Adenine Dinucleotide (FAD), a coenzyme of glucose oxidase (GOx), is the active center of the catalytic site, conformation of which could determine the activity of enzyme, it is important to understand the dynamic mechanism of its conformational mobility while GOx is adsorbed on SWCNTs with multiple orientations. However, this dynamic mechanism still remains unclear at the atomic level due to the coenzyme being embedded in the apo-GOx and the limitations of appropriate experimental methods. In this study, a molecular dynamics (MD) simulation was performed to investigate the conformational mobility mechanism of the coenzyme. The trajectory and the interaction energy clearly indicate that the adsorption of GOx onto SWCNTs plays an important role in the conformational mobility of the coenzyme, and its mobility is greatly affected by the distribution of water molecules due to it being hydrophobic.

Supeng Pei, Song Qu, Yongming Zhang

Sensors • 2010

The novel highly ordered mesoporous carbon (known as FDU-15), prepared by the organic-organic self-assembly method was been used for first time for the immobilization of hemoglobin (Hb) and its bioelectrochemical properties were studied. The resulting Hb/FDU-15 film provided a favorable microenvironment for Hb to perform direct electron transfers at the electrode. The immobilized Hb also displayed its good electrocatalytic activity for the reduction of hydrogen peroxide. The results demonstrate that mesoporous carbon FDU-15 can improve the Hb loading with retention of its bioactivity and greatly promote the direct electron transfer, which can be attributed to its high specific surface area, uniform ordered porous structure, suitable pore size and biocompatibility. Our present study may provide an alternative way for the construction of nanostructure biofunctional surfaces and pave the way for its application to biosensors.

Christina G. Antipova, Yulia Parunova, M. Vishnevskaya et al.

2019 12th International Conference on Developments in eSystems Engineering (DeSE) • 2019

Flexible electroconductive hydrogel shown as a promising material for enzyme and bacterial bioelectrochemical systems. For hydrogel synthesis biocompatible polymers PEDOT PSS, carrageenan and polyvinyl alcohol were used. It is shown the mechanical properties of hydrogel and provided an electronic microscopy investigation. The oxidation processes on the electrode with enzymes and bacterial cells are demonstrated. Chosen materials and methods of synthesis did not provide any nonbiocompatible substances in hydrogels. Thus, presented materials can be promising for flexible electrodes design for biocompatible applications.

Y. C. Wu, H. Fu, H. Wen et al.

IOP Conference Series: Earth and Environmental Science • 2019

Diclofenac sodium is an extensively consumed non-steroidal anti-inflammatory drug for certain non-rheumatic diseases and frequently detected at surface water. This work we studied the degradation process of diclofenac sodium in an anodic chambers of microbial fuel cells. It was found that biodegradation of diclofenac sodium could be achieved in the microbial fuel cells, and the removal rate of diclofenac sodium was accelerated after bioelectrochemical activity microorganism acclimation. The highest removal rate can reach up to 30.73% after 2 weeks of operation. The results also showed that weak acid (pH=5.5) condition favour the degradation of diclofenac sodium, while low temperature condition inhibited its degradation. This work provided a new way to remove diclofenac sodium from wastewater.

A. Capodaglio, D. Molognoni, A. Callegari

ECMS 2015 Proceedings edited by: Valeri M. Mladenov, Petia Georgieva, Grisha Spasov, Galidiya Petrova • 2015

Microbial Fuel Cells (MFCs) are bioelectrochemical systems that directly convert chemical energy contained in organic matter bioconvertible substrate into electrical energy. Since the mid-90’s, researchers have attempted to simulate the bioelectrochemical activity of MFCs: in this paper, in order to develop an enhanced model capable of describing a complex bacterial community, such as that of a MFC, an earlier model formulated by Pinto et al. (2010) has been integrated with the ASM2d model, representing complex biological systems with multiple substrates (Henze et al., 2013). The resulting model is herein described, together with its application to long series of MFC operational data. Results are discussed, confirming the good performance of the new model.

Danijela Randjelovic, O. Jakšić, B. Popović et al.

2019 IEEE 31st International Conference on Microelectronics (MIEL) • 2019

Microbial fuel cells (MFC) present bioelectrochemical systems that allow generation of electricity during anaerobic respiration of selected bacterial species. They have very promising applications in wastewater purification systems, as biosensors or as alternative power source. This work is a result of joint multidisciplinary research and presents preliminary experimental results obtained by electrical characterization of a single-chamber MFC. The goal of research was to study activity of MFC and estimate its internal resistance.

Wencheng Wang, Lijun Yan, Fan Shi et al.

Sensors • 2015

By using the hydrothermal method, carbon microspheres (CMS) were fabricated and used for electrode modification. The characteristics of CMS were investigated using various techniques. The biocompatible sensing platform was built by immobilizing hemoglobin (Hb) on the micrometer-sized CMS-modified electrode with a layer of chitosan membrane. On the cyclic voltammogram, a couple of quasi-reversible cathodic and anodic peaks appeared, showing that direct electrochemistry of Hb with the working electrode was achieved. The catalytic reduction peak currents of the bioelectrode to trichloroacetic acid was established in the linear range of 2.0~70.0 mmol·L−1 accompanied by a detection limit of 0.30 mmol·L−1 (3σ). The modified electrode displayed favorable sensitivity, good reproducibility and stability, which suggests that CMS is promising for fabricating third-generation bioelectrochemical sensors.