WorldWideScience

Sample records for fed bioelectrochemical systems

  1. Reactor Design for Bioelectrochemical Systems

    KAUST Repository

    Mohanakrishna, G.

    2017-12-01

    Bioelectrochemical systems (BES) are novel hybrid systems which are designed to generate renewable energy from the low cost substrate in a sustainable way. Microbial fuel cells (MFCs) are the well studied application of BES systems that generate electricity from the wide variety of organic components and wastewaters. MFC mechanism deals with the microbial oxidation of organic molecules for the production of electrons and protons. The MFC design helps to build the electrochemical gradient on anode and cathode which leads for the bioelectricity generation. As whole reactions of MFCs happen at mild environmental and operating conditions and using waste organics as the substrate, it is defined as the sustainable and alternative option for global energy needs and attracted worldwide researchers into this research area. Apart from MFC, BES has other applications such as microbial electrolysis cells (MECs) for biohydrogen production, microbial desalinations cells (MDCs) for water desalination, and microbial electrosynthesis cells (MEC) for value added products formation. All these applications are designed to perform efficiently under mild operational conditions. Specific strains of bacteria or specifically enriched microbial consortia are acting as the biocatalyst for the oxidation and reduction of BES. Detailed function of the biocatalyst has been discussed in the other chapters of this book.

  2. Reactor Design for Bioelectrochemical Systems

    KAUST Repository

    Mohanakrishna, G.; Kalathil, Shafeer; Pant, Deepak

    2017-01-01

    Bioelectrochemical systems (BES) are novel hybrid systems which are designed to generate renewable energy from the low cost substrate in a sustainable way. Microbial fuel cells (MFCs) are the well studied application of BES systems that generate electricity from the wide variety of organic components and wastewaters. MFC mechanism deals with the microbial oxidation of organic molecules for the production of electrons and protons. The MFC design helps to build the electrochemical gradient on anode and cathode which leads for the bioelectricity generation. As whole reactions of MFCs happen at mild environmental and operating conditions and using waste organics as the substrate, it is defined as the sustainable and alternative option for global energy needs and attracted worldwide researchers into this research area. Apart from MFC, BES has other applications such as microbial electrolysis cells (MECs) for biohydrogen production, microbial desalinations cells (MDCs) for water desalination, and microbial electrosynthesis cells (MEC) for value added products formation. All these applications are designed to perform efficiently under mild operational conditions. Specific strains of bacteria or specifically enriched microbial consortia are acting as the biocatalyst for the oxidation and reduction of BES. Detailed function of the biocatalyst has been discussed in the other chapters of this book.

  3. Bioelectrochemical Systems for Indirect Biohydrogen Production

    KAUST Repository

    Regan, John M.

    2014-01-01

    Bioelectrochemical systems involve the use of exoelectrogenic (i.e., anode-reducing) microbes to produce current in conjunction with the oxidation of reduced compounds. This current can be used directly for power in a microbial fuel cell, but there are alternate uses of this current. One such alternative is the production of hydrogen in a microbial electrolysis cell (MEC), which accomplishes cathodic proton reduction with a slight applied potential by exploiting the low redox potential produced by exoelectrogens at the anode. As an indirect approach to biohydrogen production, these systems are not subject to the hydrogen yield constraints of fermentative processes and have been proven to work with virtually any biodegradable organic substrate. With continued advancements in reactor design to reduce the system internal resistance, increase the specific surface area for anode biofilm development, and decrease the material costs, MECs may emerge as a viable alternative technology for biohydrogen production. Moreover, these systems can also incorporate other value-added functionalities for applications in waste treatment, desalination, and bioremediation.

  4. Food and agricultural wastes as substrates for bioelectrochemical system (BES)

    NARCIS (Netherlands)

    ElMekawy, Ahmed; Srikanth, Sandipam; Bajracharya, Suman; Hegab, H.M.; Nigam, Poonam Singh; Singh, Anoop; Mohan, S.V.; Pant, Deepak

    2015-01-01

    Bioelectrochemical systems (BESs) are one of the recent promising technologies developed for their multi-faceted applications such as bioenergy generation, wastewater treatment and synthesis of value added chemicals. Among these applications, microbial fuel cells (MFCs) for wastewater treatment

  5. Optimal Set Anode Potentials Vary in Bioelectrochemical Systems

    KAUST Repository

    Wagner, Rachel C.

    2010-08-15

    In bioelectrochemical systems (BESs), the anode potential can be set to a fixed voltage using a potentiostat, but there is no accepted method for defining an optimal potential. Microbes can theoretically gain more energy by reducing a terminal electron acceptor with a more positive potential, for example oxygen compared to nitrate. Therefore, more positive anode potentials should allow microbes to gain more energy per electron transferred than a lower potential, but this can only occur if the microbe has metabolic pathways capable of capturing the available energy. Our review of the literature shows that there is a general trend of improved performance using more positive potentials, but there are several notable cases where biofilm growth and current generation improved or only occurred at more negative potentials. This suggests that even with diverse microbial communities, it is primarily the potential of the terminal respiratory proteins used by certain exoelectrogenic bacteria, and to a lesser extent the anode potential, that determines the optimal growth conditions in the reactor. Our analysis suggests that additional bioelectrochemical investigations of both pure and mixed cultures, over a wide range of potentials, are needed to better understand how to set and evaluate optimal anode potentials for improving BES performance. © 2010 American Chemical Society.

  6. Bioelectrochemical Systems for Indirect Biohydrogen Production

    KAUST Repository

    Regan, John M.; Yan, Hengjing

    2014-01-01

    by exoelectrogens at the anode. As an indirect approach to biohydrogen production, these systems are not subject to the hydrogen yield constraints of fermentative processes and have been proven to work with virtually any biodegradable organic substrate

  7. RESOURCE RECOVERY BY OSMOTIC BIOELECTROCHEMICAL SYSTEMS  TOWARDS SUSTAINABLE WASTEWATER TREATMENT

    OpenAIRE

    Qin, Mohan

    2017-01-01

    Recovering valuable resources from wastewater will transform wastewater management from a treatment focused to sustainability focused strategy, and creates the need for new technology development. An innovative treatment concept - osmotic bioelectrochemical system (OsBES), which is based on cooperation between bioelectrochemical systems (BES) and forward osmosis (FO), has been introduced and studied in the past few years. An OsBES can accomplish simultaneous treatment of wastewater and recove...

  8. Development of Bioelectrochemical Systems to Promote Sustainable Agriculture

    Directory of Open Access Journals (Sweden)

    Xiaojin Li

    2015-06-01

    Full Text Available Bioelectrochemical systems (BES are a newly emerged technology for energy-efficient water and wastewater treatment. Much effort as well as significant progress has been made in advancing this technology towards practical applications treating various types of waste. However, BES application for agriculture has not been well explored. Herein, studies of BES related to agriculture are reviewed and the potential applications of BES for promoting sustainable agriculture are discussed. BES may be applied to treat the waste/wastewater from agricultural production, minimizing contaminants, producing bioenergy, and recovering useful nutrients. BES can also be used to supply irrigation water via desalinating brackish water or producing reclaimed water from wastewater. The energy generated in BES can be used as a power source for wireless sensors monitoring the key parameters for agricultural activities. The importance of BES to sustainable agriculture should be recognized, and future development of this technology should identify proper application niches with technological advancement.

  9. A Review of Modeling Bioelectrochemical Systems: Engineering and Statistical Aspects

    Directory of Open Access Journals (Sweden)

    Shuai Luo

    2016-02-01

    Full Text Available Bioelectrochemical systems (BES are promising technologies to convert organic compounds in wastewater to electrical energy through a series of complex physical-chemical, biological and electrochemical processes. Representative BES such as microbial fuel cells (MFCs have been studied and advanced for energy recovery. Substantial experimental and modeling efforts have been made for investigating the processes involved in electricity generation toward the improvement of the BES performance for practical applications. However, there are many parameters that will potentially affect these processes, thereby making the optimization of system performance hard to be achieved. Mathematical models, including engineering models and statistical models, are powerful tools to help understand the interactions among the parameters in BES and perform optimization of BES configuration/operation. This review paper aims to introduce and discuss the recent developments of BES modeling from engineering and statistical aspects, including analysis on the model structure, description of application cases and sensitivity analysis of various parameters. It is expected to serves as a compass for integrating the engineering and statistical modeling strategies to improve model accuracy for BES development.

  10. Bioelectrochemical Biorefining

    Energy Technology Data Exchange (ETDEWEB)

    Borole, Abhijeet P. [ORNL

    2017-12-01

    Bioelectrochemical biorefining is a new concept which has evolved from the field of microbial fuel cells and electrolysis cells. It targets integration of microbial electrochemical cells into the biorefinery. The idea is to use low value resources to generate electrons and then use the electrons to produce value-added products. This can enable production of fuels and chemicals from waste and biomass using electrons as intermediates. Thus, the name: Bioelectrochemical Biorefining. Electrons are the simplest and most common ‘energy carriers’ of many energy transfer systems and energetic molecules. Thus, using them as the vehicle for conversion of existing renewable resources into products needed for the 21st century is the primary goal of this marriage between microbial electrochemical technology and biorefineries.

  11. Microbial metabolism and activity in terms of nitrate removal in bioelectrochemical systems

    International Nuclear Information System (INIS)

    Huang, Baocheng; Feng, Huajun; Ding, Yangcheng; Zheng, Xin; Wang, Meizhen; Li, Na; Shen, Dongsheng; Zhang, Haiyang

    2013-01-01

    Highlights: • Influence of current on biofilm formation in BES was investigated. • Biofilm formation activity supplying with organic differed with inorganic. • Discussed the influence of signaling molecule and EPS on biofilm formation. -- Abstract: Bioelectrochemical systems (BESs) are a promising technology for generating energy while treating wastewater. By utilizing the electron transfer between the anode and cathode, nitrate can be effectively removed from the BES. Our previous studies show that the carbon source and C/N ratio influences nitrate removal performance. The study presented here investigates how biofilm formation, nitrate removal and signaling molecule release are related in the BESs fed with glucose, starch and HCO 3 − . The results indicate that increasing the current can benefit signaling molecule (DSF) release and extracellular polymeric substances (EPS) excretion, which improves biofilm formation. However, when the current exceeds the optimum value, the influence becomes adverse. Nitrate removal was also improved with increased current, though different carbon sources showed different trends. The highest nitrate removal efficiency of 1.23 ± 0.27, 1.38 ± 0.09, 1.80 ± 0.02 mmol L −1 d −1 for the BESs fed with glucose, starch and HCO 3 − were achieved, respectively. This paper studied the bacterial habits in a BES to better acquire and regulate the reaction process, with the aim of achieving good pollutant removal performance

  12. Geobacter anodireducens sp. nov., an exoelectrogenic microbe in bioelectrochemical systems

    KAUST Repository

    Sun, D.

    2014-07-22

    © 2014 IUMS. A previously isolated exoelectrogenic bacterium, strain SD-1(T), was further characterized and identified as a representative of a novel species of the genus Geobacter. Strain SD-1(T) was Gram-negative, aerotolerant, anaerobic, non-spore-forming, non-fermentative and non-motile. Cells were short, curved rods (0.8-1.3 µm long and 0.3 µm in diameter). Growth of strain SD-1(T) was observed at 15-42 °C and pH 6.0-8.5, with optimal growth at 30-35 °C and pH 7. Analysis of 16S rRNA gene sequences indicated that the isolate was a member of the genus Geobacter, with the closest known relative being Geobacter sulfurreducens PCA(T) (98% similarity). Similar to other members of the genus Geobacter, strain SD-1(T) used soluble or insoluble Fe(III) as the sole electron acceptor coupled with the oxidation of acetate. However, SD-1(T) could not reduce fumarate as an electron acceptor with acetate oxidization, which is an important physiological trait for G. sulfurreducens. Moreover, SD-1(T) could grow in media containing as much as 3% NaCl, while G. sulfurreducens PCA(T) can tolerate just half this concentration, and this difference in salt tolerance was even more obvious when cultivated in bioelectrochemical systems. DNA-DNA hybridization analysis of strain SD-1(T) and its closest relative, G. sulfurreducens ATCC 51573(T), showed a relatedness of 61.6%. The DNA G+C content of strain SD-1(T) was 58.9 mol%. Thus, on the basis of these characteristics, strain SD-1(T) was not assigned to G. sulfurreducens, and was instead classified in the genus Geobacter as a representative of a novel species. The name Geobacter anodireducens sp. nov. is proposed, with the type strain SD-1(T) ( = CGMCC 1.12536(T) = KCTC 4672(T)).

  13. Gas-permeable hydrophobic tubular membranes for ammonia recovery in bio-electrochemical systems

    NARCIS (Netherlands)

    Kuntke, P.; Zamora, P.; Saakes, M.; Buisman, C.J.N.; Hamelers, H.V.M.

    2016-01-01

    The application of a gas-permeable hydrophobic tubular membrane in bio-electrochemical systems enables efficient recovery of ammonia (NH3) from their cathode compartments. Due to a hydrogen evolution reaction at the cathode, no chemical addition was required to increase the pH for

  14. An overview on emerging bioelectrochemical systems (BESs): Technology for sustainable electricity, waste remediation, resource recovery, chemical production and beyond

    NARCIS (Netherlands)

    Bajracharya, S.; Sharma, M.; Mohanakrishna, Gunda; Benneton, Xochitl Dominguez; Strik, D.P.B.T.B.; Sarma, Priyangshu M.; Pant, Deepak

    2016-01-01

    Bioelectrochemical systems (BESs) are unique systems capable of converting chemical energy into electrical energy (and vice-versa) while employing microbes as catalysts. Such organic wastes including low-strength wastewaters and lignocellulosic biomass were converted into electricity with microbial

  15. Biodegradation of polycyclic aromatic hydrocarbons: Using microbial bioelectrochemical systems to overcome an impasse.

    Science.gov (United States)

    Kronenberg, Maria; Trably, Eric; Bernet, Nicolas; Patureau, Dominique

    2017-12-01

    Polycyclic aromatic hydrocarbons (PAHs) are hardly biodegradable carcinogenic organic compounds. Bioremediation is a commonly used method for treating PAH contaminated environments such as soils, sediment, water bodies and wastewater. However, bioremediation has various drawbacks including the low abundance, diversity and activity of indigenous hydrocarbon degrading bacteria, their slow growth rates and especially a limited bioavailability of PAHs in the aqueous phase. Addition of nutrients, electron acceptors or co-substrates to enhance indigenous microbial activity is costly and added chemicals often diffuse away from the target compound, thus pointing out an impasse for the bioremediation of PAHs. A promising solution is the adoption of bioelectrochemical systems. They guarantee a permanent electron supply and withdrawal for microorganisms, thereby circumventing the traditional shortcomings of bioremediation. These systems combine biological treatment with electrochemical oxidation/reduction by supplying an anode and a cathode that serve as an electron exchange facility for the biocatalyst. Here, recent achievements in polycyclic aromatic hydrocarbon removal using bioelectrochemical systems have been reviewed. This also concerns PAH precursors: total petroleum hydrocarbons and diesel. Removal performances of PAH biodegradation in bioelectrochemical systems are discussed, focussing on configurational parameters such as anode and cathode designs as well as environmental parameters like porosity, salinity, adsorption and conductivity of soil and sediment that affect PAH biodegradation in BESs. The still scarcely available information on microbiological aspects of bioelectrochemical PAH removal is summarised here. This comprehensive review offers a better understanding of the parameters that affect the removal of PAHs within bioelectrochemical systems. In addition, future experimental setups are proposed in order to study syntrophic relationships between PAH

  16. A novel bioelectrochemical system for chemical-free permanent treatment of acid mine drainage.

    Science.gov (United States)

    Pozo, Guillermo; Pongy, Sebastien; Keller, Jürg; Ledezma, Pablo; Freguia, Stefano

    2017-12-01

    The mining sector is currently under unprecedented pressure due to stringent environmental regulations. As a consequence, a permanent acid mine drainage (AMD) treatment is increasingly being regarded as a desirable target with direct benefits for the environment and the operational and economic viability of the resources sector. In this study we demonstrate that a novel bioelectrochemical system (BES) can deliver permanent treatment of acid mine drainage without chemical dosing. The technology consists of a two-cell bioelectrochemical setup to enable the removal of sulfate from the ongoing reduction-oxidation sulfur cycle to less than 550 mg L -1 (85 ± 2% removal from a real AMD of an abandoned silver mine), thereby also reducing salinity at an electrical energy requirement of 10 ± 0.3 kWh kg -1 of SO 4 2- -S removed. In addition, the BES operation drove the removal and recovery of the main cations Al, Fe, Mg, Zn at rates of 151 ± 0 g Al m -3  d -1 , 179 ± 1 g Fe m -3  d -1 , 172 ± 1 g Mg m -3  d -1 and 46 ± 0 g Zn m -3  d -1 into a concentrate stream containing 263 ± 2 mg Al, 279 ± 2 mg Fe, 152 ± 0 mg Mg and 90 ± 0 mg Zn per gram of solid precipitated after BES fed-rate control treatment. The solid metal-sludge was twice less voluminous and 9 times more readily settleable than metal-sludge precipitated using NaOH. The continuous BES treatment also demonstrated the concomitant precipitation of rare earth elements together with yttrium (REY), with up to 498 ± 70 μg Y, 166 ± 27 μg Nd, 155 ± 14 μg Gd per gram of solid, among other high-value metals. The high-REY precipitates could be used to offset the treatment costs. Copyright © 2017 Elsevier Ltd. All rights reserved.

  17. Analysis of electrode microbial communities in an up-flow bioelectrochemical system treating azo dye wastewater

    International Nuclear Information System (INIS)

    Cui, Min-Hua; Cui, Dan; Gao, Lei; Cheng, Hao-Yi; Wang, Ai-Jie

    2016-01-01

    Bioelectrochemical system (BES) is a rapidly developing technology covering contamination remediation, resource recovery and power generation. Electrode biofilms play a key role in BES operation. In this work, a single chamber up-flow bioelectrochemical system (UBES) was assembled with two preinoculated anodes and two raw cathodes for azo dye wastewater treatment. Microbial community structures of these electrodes after long-term operation (more than 200 days) were carried out by high-throughput Illumina 16S rRNA gene MiSeq sequencing platform. Microorganisms belonging to Enterobacter, Desulfovibrio and Enterococcus, which are capable of bidirectional extracellular electron transfer, were found to be the dominant members in all biofilms. Neither the polarity nor the position of the electrodes obviously altered the microbial community structures. This study provides a feasible strategy to build electrode active biofilms in a BES for azo dye wastewater treatment and gives great inspirations to bring this technology closer to application.

  18. Enhanced removal of petroleum hydrocarbons using a bioelectrochemical remediation system with pre-cultured anodes

    International Nuclear Information System (INIS)

    Venkidusamy, Krishnaveni; Megharaj, Mallavarapu; Marzorati, Massimo; Lockington, Robin; Naidu, Ravi

    2016-01-01

    Bioelectrochemical remediation (BER) systems such as microbial fuel cells (MFCs) have recently emerged as a green technology for the effective remediation of petroleum hydrocarbon contaminants (PH) coupled with simultaneous energy recovery. Recent research has shown that biofilms previously enriched for substrate degrading bacteria resulted in excellent performance in terms of substrate removal and electricity generation but the effects on hydrocarbon contaminant degradation were not examined. Here we investigate the differences between enriched biofilm anodes and freshly inoculated new anodes in diesel fed single chamber mediatorless microbial fuel cells (DMFC) using various techniques for the enhancement of PH contaminant remediation with concomitant electricity generation. An anodophilic microbial consortium previously selected for over a year through continuous culturing with a diesel concentration of about 800 mg l"−"1 and which now showed complete removal of this concentration of diesel within 30 days was compared to that of a freshly inoculated new anode MFC (showing 83.4% removal of diesel) with a simultaneous power generation of 90.81 mW/m"2 and 15.04 mW/m"2 respectively. The behaviour of pre-cultured anodes at a higher concentration of PH (8000 mg l"−"1) was also investigated. Scanning electron microscopy observation revealed a thick biofilm covering the pre-cultured anodic electrode but not the anode from the freshly inoculated MFC. High resolution imaging showed the presence of thin 60 nm diametre pilus-like projections emanating from the cells. Anodic microbial community profiling confirmed that the selection for diesel degrading exoelectrogenic bacteria had occurred. Identification of a biodegradative gene (alkB) provided strong evidence of the catabolic pathway used for diesel degradation in the DMFCs.

  19. Enhanced removal of petroleum hydrocarbons using a bioelectrochemical remediation system with pre-cultured anodes

    Energy Technology Data Exchange (ETDEWEB)

    Venkidusamy, Krishnaveni [Centre for Environmental Risk Assessment and Remediation (CERAR), University of South (Australia); CRC for Contamination Assessment and Remediation of the Environment (CRCCARE), Mawson Lakes, SA5095 (Australia); Megharaj, Mallavarapu, E-mail: megh.mallavarapu@newcastle.edu.au [Centre for Environmental Risk Assessment and Remediation (CERAR), University of South (Australia); CRC for Contamination Assessment and Remediation of the Environment (CRCCARE), Mawson Lakes, SA5095 (Australia); Global Centre for Environmental Remediation, Faculty of Science and Information Technology, The University of Newcastle, Callaghan, NSW 2308 (Australia); Marzorati, Massimo [Laboratory for Microbial Ecology and Technology (LabMET), Gent University, 9000 Gent (Belgium); Lockington, Robin [Centre for Environmental Risk Assessment and Remediation (CERAR), University of South (Australia); CRC for Contamination Assessment and Remediation of the Environment (CRCCARE), Mawson Lakes, SA5095 (Australia); Naidu, Ravi [Centre for Environmental Risk Assessment and Remediation (CERAR), University of South (Australia); CRC for Contamination Assessment and Remediation of the Environment (CRCCARE), Mawson Lakes, SA5095 (Australia); Global Centre for Environmental Remediation, Faculty of Science and Information Technology, The University of Newcastle, Callaghan, NSW 2308 (Australia)

    2016-01-01

    Bioelectrochemical remediation (BER) systems such as microbial fuel cells (MFCs) have recently emerged as a green technology for the effective remediation of petroleum hydrocarbon contaminants (PH) coupled with simultaneous energy recovery. Recent research has shown that biofilms previously enriched for substrate degrading bacteria resulted in excellent performance in terms of substrate removal and electricity generation but the effects on hydrocarbon contaminant degradation were not examined. Here we investigate the differences between enriched biofilm anodes and freshly inoculated new anodes in diesel fed single chamber mediatorless microbial fuel cells (DMFC) using various techniques for the enhancement of PH contaminant remediation with concomitant electricity generation. An anodophilic microbial consortium previously selected for over a year through continuous culturing with a diesel concentration of about 800 mg l{sup −1} and which now showed complete removal of this concentration of diesel within 30 days was compared to that of a freshly inoculated new anode MFC (showing 83.4% removal of diesel) with a simultaneous power generation of 90.81 mW/m{sup 2} and 15.04 mW/m{sup 2} respectively. The behaviour of pre-cultured anodes at a higher concentration of PH (8000 mg l{sup −1}) was also investigated. Scanning electron microscopy observation revealed a thick biofilm covering the pre-cultured anodic electrode but not the anode from the freshly inoculated MFC. High resolution imaging showed the presence of thin 60 nm diametre pilus-like projections emanating from the cells. Anodic microbial community profiling confirmed that the selection for diesel degrading exoelectrogenic bacteria had occurred. Identification of a biodegradative gene (alkB) provided strong evidence of the catabolic pathway used for diesel degradation in the DMFCs.

  20. Enhanced start-up of anaerobic facultatively autotrophic biocathodes in bioelectrochemical systems

    KAUST Repository

    Zaybak, Zehra; Pisciotta, John M.; Tokash, Justin C.; Logan, Bruce E.

    2013-01-01

    Biocathodes in bioelectrochemical systems (BESs) can be used to convert CO2 into diverse organic compounds through a process called microbial electrosynthesis. Unfortunately, start-up of anaerobic biocathodes in BESs is a difficult and time consuming process. Here, a pre-enrichment method was developed to improve start-up of anaerobic facultatively autotrophic biocathodes capable of using cathodes as the electron donor (electrotrophs) and CO2 as the electron acceptor. Anaerobic enrichment of bacteria from freshwater bog sediment samples was first performed in batch cultures fed with glucose and then used to inoculate BES cathode chambers set at -0.4V (versus a standard hydrogen electrode; SHE). After two weeks of heterotrophic operation of BESs, CO2 was provided as the sole electron acceptor and carbon source. Consumption of electrons from cathodes increased gradually and was sustained for about two months in concert with a significant decrease in cathode chamber headspace CO2. The maximum current density consumed was -34±4mA/m2. Biosynthesis resulted in organic compounds that included butanol, ethanol, acetate, propionate, butyrate, and hydrogen gas. Bacterial community analyses based on 16S rRNA gene clone libraries revealed Trichococcus palustris DSM 9172 (99% sequence identity) as the prevailing species in biocathode communities, followed by Oscillibacter sp. and Clostridium sp. Isolates from autotrophic cultivation were most closely related to Clostridium propionicum (99% sequence identity; ZZ16), Clostridium celerecrescens (98-99%; ZZ22, ZZ23), Desulfotomaculum sp. (97%; ZZ21), and Tissierella sp. (98%; ZZ25). This pre-enrichment procedure enables simplified start-up of anaerobic biocathodes for applications such as electrofuel production by facultatively autotrophic electrotrophs. © 2013 Elsevier B.V.

  1. Enhanced start-up of anaerobic facultatively autotrophic biocathodes in bioelectrochemical systems

    KAUST Repository

    Zaybak, Zehra

    2013-12-01

    Biocathodes in bioelectrochemical systems (BESs) can be used to convert CO2 into diverse organic compounds through a process called microbial electrosynthesis. Unfortunately, start-up of anaerobic biocathodes in BESs is a difficult and time consuming process. Here, a pre-enrichment method was developed to improve start-up of anaerobic facultatively autotrophic biocathodes capable of using cathodes as the electron donor (electrotrophs) and CO2 as the electron acceptor. Anaerobic enrichment of bacteria from freshwater bog sediment samples was first performed in batch cultures fed with glucose and then used to inoculate BES cathode chambers set at -0.4V (versus a standard hydrogen electrode; SHE). After two weeks of heterotrophic operation of BESs, CO2 was provided as the sole electron acceptor and carbon source. Consumption of electrons from cathodes increased gradually and was sustained for about two months in concert with a significant decrease in cathode chamber headspace CO2. The maximum current density consumed was -34±4mA/m2. Biosynthesis resulted in organic compounds that included butanol, ethanol, acetate, propionate, butyrate, and hydrogen gas. Bacterial community analyses based on 16S rRNA gene clone libraries revealed Trichococcus palustris DSM 9172 (99% sequence identity) as the prevailing species in biocathode communities, followed by Oscillibacter sp. and Clostridium sp. Isolates from autotrophic cultivation were most closely related to Clostridium propionicum (99% sequence identity; ZZ16), Clostridium celerecrescens (98-99%; ZZ22, ZZ23), Desulfotomaculum sp. (97%; ZZ21), and Tissierella sp. (98%; ZZ25). This pre-enrichment procedure enables simplified start-up of anaerobic biocathodes for applications such as electrofuel production by facultatively autotrophic electrotrophs. © 2013 Elsevier B.V.

  2. Enhanced bioremediation of hydrocarbon-contaminated soil using pilot-scale bioelectrochemical systems

    International Nuclear Information System (INIS)

    Lu, Lu; Yazdi, Hadi; Jin, Song; Zuo, Yi; Fallgren, Paul H.; Ren, Zhiyong Jason

    2014-01-01

    Highlights: • Pilot bioelectrochemical system showed high-performance hydrocarbon remediation. • Radius of influence characterization demonstrated system efficacy. • Current serves as degradation indicator. - Abstract: Two column-type bioelectrochemical system (BES) modules were installed into a 50-L pilot scale reactor packed with diesel-contaminated soils to investigate the enhancement of passive biodegradation of petroleum compounds. By using low cost electrodes such as biochar and graphite granule as non-exhaustible solid-state electron acceptors, the results show that 82.1–89.7% of the total petroleum hydrocarbon (TPH) was degraded after 120 days across 1–34 cm radius of influence (ROI) from the modules. This represents a maximum of 241% increase of biodegradation compared to a baseline control reactor. The current production in the BESs correlated with the TPH removal, reaching the maximum output of 70.4 ± 0.2 mA/m 2 . The maximum ROI of the BES, deducting influence from the baseline natural attenuation, was estimated to be more than 90 cm beyond the edge of the reactor (34 cm), and exceed 300 cm should a non-degradation baseline be used. The ratio of the projected ROI to the radius of BES (ROB) module was 11–12. The results suggest that this BES can serve as an innovative and sustainable technology for enhanced in situ bioremediation of petroleum hydrocarbons in large field scale, with additional benefits of electricity production and being integrated into existing field infrastructures

  3. Enhanced bioremediation of hydrocarbon-contaminated soil using pilot-scale bioelectrochemical systems

    Energy Technology Data Exchange (ETDEWEB)

    Lu, Lu; Yazdi, Hadi [Department of Civil, Environmental, and Architectural Engineering, University of Colorado Boulder, Boulder, CO (United States); Jin, Song [Department of Civil and Architectural Engineering, University of Wyoming, Laramie, WY (United States); Zuo, Yi [Chevron Energy Technology Company, San Ramon, CA (United States); Fallgren, Paul H. [Department of Civil Engineering, University of Colorado Denver, Denver, CO (United States); Ren, Zhiyong Jason, E-mail: jason.ren@colorado.edu [Department of Civil, Environmental, and Architectural Engineering, University of Colorado Boulder, Boulder, CO (United States); Department of Civil Engineering, University of Colorado Denver, Denver, CO (United States)

    2014-06-01

    Highlights: • Pilot bioelectrochemical system showed high-performance hydrocarbon remediation. • Radius of influence characterization demonstrated system efficacy. • Current serves as degradation indicator. - Abstract: Two column-type bioelectrochemical system (BES) modules were installed into a 50-L pilot scale reactor packed with diesel-contaminated soils to investigate the enhancement of passive biodegradation of petroleum compounds. By using low cost electrodes such as biochar and graphite granule as non-exhaustible solid-state electron acceptors, the results show that 82.1–89.7% of the total petroleum hydrocarbon (TPH) was degraded after 120 days across 1–34 cm radius of influence (ROI) from the modules. This represents a maximum of 241% increase of biodegradation compared to a baseline control reactor. The current production in the BESs correlated with the TPH removal, reaching the maximum output of 70.4 ± 0.2 mA/m{sup 2}. The maximum ROI of the BES, deducting influence from the baseline natural attenuation, was estimated to be more than 90 cm beyond the edge of the reactor (34 cm), and exceed 300 cm should a non-degradation baseline be used. The ratio of the projected ROI to the radius of BES (ROB) module was 11–12. The results suggest that this BES can serve as an innovative and sustainable technology for enhanced in situ bioremediation of petroleum hydrocarbons in large field scale, with additional benefits of electricity production and being integrated into existing field infrastructures.

  4. Ethanol generation, oxidation and energy production in a cooperative bioelectrochemical system.

    Science.gov (United States)

    Pagnoncelli, Kamila C; Pereira, Andressa R; Sedenho, Graziela C; Bertaglia, Thiago; Crespilho, Frank N

    2018-08-01

    Integrating in situ biofuel production and energy conversion into a single system ensures the production of more robust networks as well as more renewable technologies. For this purpose, identifying and developing new biocatalysts is crucial. Herein, is reported a bioelectrochemical system consisting of alcohol dehydrogenase (ADH) and Saccharomyces cerevisiae, wherein both function cooperatively for ethanol production and its bioelectrochemical oxidation. Here, it is shown that it is possible to produce ethanol and use it as a biofuel in a tandem manner. The strategy is to employ flexible carbon fibres (FCF) electrode that could adsorb both the enzyme and the yeast cells. Glucose is used as a substrate for the yeast for the production of ethanol, while the enzyme is used to catalyse the oxidation of ethanol to acetaldehyde. Regarding the generation of reliable electricity based on electrochemical systems, the biosystem proposed in this study operates at a low temperature and ethanol production is proportional to the generated current. With further optimisation of electrode design, we envision the use of the cooperative biofuel cell for energy conversion and management of organic compounds. Copyright © 2018 Elsevier B.V. All rights reserved.

  5. Metal-based anode for high performance bioelectrochemical systems through photo-electrochemical interaction

    Science.gov (United States)

    Liang, Yuxiang; Feng, Huajun; Shen, Dongsheng; Long, Yuyang; Li, Na; Zhou, Yuyang; Ying, Xianbin; Gu, Yuan; Wang, Yanfeng

    2016-08-01

    This paper introduces a novel composite anode that uses light to enhance current generation and accelerate biofilm formation in bioelectrochemical systems. The composite anode is composed of 316L stainless steel substrate and a nanostructured α-Fe2O3 photocatalyst (PSS). The electrode properties, current generation, and biofilm properties of the anode are investigated. In terms of photocurrent, the optimal deposition and heat-treatment times are found to be 30 min and 2 min, respectively, which result in a maximum photocurrent of 0.6 A m-2. The start-up time of the PSS is 1.2 days and the maximum current density is 2.8 A m-2, twice and 25 times that of unmodified anode, respectively. The current density of the PSS remains stable during 20 days of illumination. Confocal laser scanning microscope images show that the PSS could benefit biofilm formation, while electrochemical impedance spectroscopy indicates that the PSS reduce the charge-transfer resistance of the anode. Our findings show that photo-electrochemical interaction is a promising way to enhance the biocompatibility of metal anodes for bioelectrochemical systems.

  6. Suitability of olive oil washing water as an electron donor in a feed batch operating bio-electrochemical system

    Directory of Open Access Journals (Sweden)

    F. G. Fermoso

    2017-06-01

    Full Text Available Olive oil washing water derived from the two-phase manufacturing process was assessed as an electron donor in a bio-electrochemical system (BES operating at 35 ºC. Start-up was carried out by using acetate as a substrate for the BES, reaching a potential of around +680 mV. After day 54, BES was fed with olive oil washing water. The degradation of olive oil washing water in the BES generated a maximum voltage potential of around +520 mV and a Chemical Oxygen Demand (COD removal efficiency of 41%. However, subsequent loads produced a decrease in the COD removal, while current and power density diminished greatly. The deterioration of these parameters could be a consequence of the accumulation of recalcitrant or inhibitory compounds, such as phenols. These results demonstrated that the use of olive oil washing water as an electron donor in a BES is feasible, although it has to be further investigated in order to make it more suitable for a real application.

  7. Suitability of olive oil washing water as an electron donor in a feed batch operating bio-electrochemical system

    International Nuclear Information System (INIS)

    Fermoso, F.G.; Fernández-Rodríguez, M.J.; Jiménez-Rodríguez, A.; Serrano, A.; Borja, R.

    2017-01-01

    Olive oil washing water derived from the two-phase manufacturing process was assessed as an electron donor in a bio-electrochemical system (BES) operating at 35 ºC. Start-up was carried out by using acetate as a substrate for the BES, reaching a potential of around +680 mV. After day 54, BES was fed with olive oil washing water. The degradation of olive oil washing water in the BES generated a maximum voltage potential of around +520 mV and a Chemical Oxygen Demand (COD) removal efficiency of 41%. However, subsequent loads produced a decrease in the COD removal, while current and power density diminished greatly. The deterioration of these parameters could be a consequence of the accumulation of recalcitrant or inhibitory compounds, such as phenols. These results demonstrated that the use of olive oil washing water as an electron donor in a BES is feasible, although it has to be further investigated in order to make it more suitable for a real application. [es

  8. Electron donation characteristics and interplays of major volatile fatty acids from anaerobically fermented organic matters in bioelectrochemical systems.

    Science.gov (United States)

    Zhang, Zhiqiang; Li, Jiamiao; Hao, Xiaoxuan; Gu, Zaoli; Xia, Siqing

    2018-02-23

    Anaerobic fermentation liquid of waste organic matters (WOMs) is rich in volatile fatty acids (VFAs), which can be treated with bioelectrochemical systems for both electrical energy recovery and organics removal. In this work, four major VFAs in the fermented WOMs supernatant were selected to examine their electron donation characteristics for power output and their complicated interplays in microbial fuel cells (MFCs). Results indicated a priority sequence of acetate, propionate, n-butyrate and i-valerate when served as the sole electron donor for electricity generation. The MFC solely fed with acetate showed the highest coulombic efficiency and power density, and the longest period for electricity production. When two of the VFAs were added with equal proportion, both acids contributed positively to electricity generation, while the selective or competitive use of substrates by diverse microorganisms behaved as an antagonism effect to prolong the degradation time of each VFA. When acetate and propionate, the preferable substrates for electricity generation, were mixed in various proportions, their large concentration difference led to improved electrical performance but decreased organic removal rate.

  9. Bioelectrochemical systems (BES) for sustainable energy production and product recovery from organic wastes and industrial wastewaters

    DEFF Research Database (Denmark)

    Pant, Deepak; Singh, Anoop; Van Bogaert, Gilbert

    2012-01-01

    Bioelectrochemical systems (BESs) are unique systems capable of converting the chemical energy of organic waste including low-strength wastewaters and lignocellulosic biomass into electricity or hydrogen/chemical products in microbial fuel cells (MFCs) or microbial electrolysis cells (MECs......) respectively, or other products formed at the cathode by an electrochemical reduction process. As compared to conventional fuel cells, BESs operate under relatively mild conditions, use a wide variety of organic substrates and mostly do not use expensive precious metals as catalysts. The recently discovered...... use of BES for product synthesis via microbial electrosynthesis have greatly expanded the horizon for these systems. Newer concepts in application as well as development of alternative materials for electrodes, separators, and catalysts, along with innovative designs have made BESs very promising...

  10. Alamethicin Suppresses Methanogenesis and Promotes Acetogenesis in Bioelectrochemical Systems

    KAUST Repository

    Zhu, Xiuping; Siegert, Michael; Yates, Matthew D.; Logan, Bruce E.

    2015-01-01

    Microbial electrosynthesis (MES) systems with mixed cultures often generate a variety of gaseous and soluble chemicals. Methane is the primary end product in mixed-culture MES because it is the thermodynamically most favorable reduction product of CO2. Here, we show that the peptaibol alamethicin selectively suppressed the growth of methanogens in mixed-culture MES systems, resulting in a shift of the solution and cathode communities to an acetate-producing system dominated by Sporomusa, a known acetogenic genus in MES systems. Archaea in the methane-producing control were dominated by Methanobrevibacter species, but no Archaea were detected in the alamethicin-treated reactors. No methane was detected in the mixed-culture reactors treated with alamethicin over 10 cycles (∼ 3 days each). Instead, acetate was produced at an average rate of 115 nmol ml(-1) day(-1), similar to the rate reported previously for pure cultures of Sporomusa ovata on biocathodes. Mixed-culture control reactors without alamethicin generated methane at nearly 100% coulombic recovery, and no acetate was detected. These results show that alamethicin is effective for the suppression of methanogen growth in MES systems and that its use enables the production of industrially relevant organic compounds by the inhibition of methanogenesis.

  11. Alamethicin Suppresses Methanogenesis and Promotes Acetogenesis in Bioelectrochemical Systems

    KAUST Repository

    Zhu, Xiuping

    2015-03-27

    Microbial electrosynthesis (MES) systems with mixed cultures often generate a variety of gaseous and soluble chemicals. Methane is the primary end product in mixed-culture MES because it is the thermodynamically most favorable reduction product of CO2. Here, we show that the peptaibol alamethicin selectively suppressed the growth of methanogens in mixed-culture MES systems, resulting in a shift of the solution and cathode communities to an acetate-producing system dominated by Sporomusa, a known acetogenic genus in MES systems. Archaea in the methane-producing control were dominated by Methanobrevibacter species, but no Archaea were detected in the alamethicin-treated reactors. No methane was detected in the mixed-culture reactors treated with alamethicin over 10 cycles (∼ 3 days each). Instead, acetate was produced at an average rate of 115 nmol ml(-1) day(-1), similar to the rate reported previously for pure cultures of Sporomusa ovata on biocathodes. Mixed-culture control reactors without alamethicin generated methane at nearly 100% coulombic recovery, and no acetate was detected. These results show that alamethicin is effective for the suppression of methanogen growth in MES systems and that its use enables the production of industrially relevant organic compounds by the inhibition of methanogenesis.

  12. Essential Data and Techniques for Conducting Microbial Fuel Cell and other Types of Bioelectrochemical System Experiments

    KAUST Repository

    Logan, Bruce E.

    2012-01-01

    Microbial fuel cells (MFCs) and other bioelectrochemical systems are new technologies that require expertise in a variety of technical areas, ranging from electrochemistry to biological wastewater treatment. There are certain data and critical information that should be included in every MFC study, such as specific surface area of the electrodes, solution conductivity, and power densities normalized to electrode surface area and volumes. Electrochemical techniques such as linear sweep voltammetry can be used to understand the performance of the MFC, but extremely slow scans are required for these biological systems compared to more traditional fuel cells. In this Minireview, the critical information needed for MFC studies is provided with examples of how results can be better conveyed through a full description of materials, the use of proper controls, and inclusion of a more complete electrochemical analysis. © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  13. Bioelectrochemical systems serve anaerobic digestion process for process monitoring and biogas upgrading

    DEFF Research Database (Denmark)

    Jin, Xiangdan

    Bioelectrochemical systems (BES), which employ microbes as catalysts to convert chemical energy stored in organic matter into sustainable electricity and high-value chemicals, is an emerging and promising technology. BES have broad applications including wastewater treatment, chemical production......, resource recovery and waste remediation. Recently, new concepts of been proposed. The purpose of this work was to optimize the AD process using BES in two aspects: developing a new volatile fatty acid (VFA) monitoring system which can be used as the AD process indicator, and for improving biogas quality...... and small external resistance were advantageous for current signal amplification. Two linear relationships between current outputs and VFA concentrations were observed. The response time was approx. 5 h and the detection range was 1 to 200 mM. The selectivity of the biosensor was demonstrated since organic...

  14. Essential Data and Techniques for Conducting Microbial Fuel Cell and other Types of Bioelectrochemical System Experiments

    KAUST Repository

    Logan, Bruce E.

    2012-04-19

    Microbial fuel cells (MFCs) and other bioelectrochemical systems are new technologies that require expertise in a variety of technical areas, ranging from electrochemistry to biological wastewater treatment. There are certain data and critical information that should be included in every MFC study, such as specific surface area of the electrodes, solution conductivity, and power densities normalized to electrode surface area and volumes. Electrochemical techniques such as linear sweep voltammetry can be used to understand the performance of the MFC, but extremely slow scans are required for these biological systems compared to more traditional fuel cells. In this Minireview, the critical information needed for MFC studies is provided with examples of how results can be better conveyed through a full description of materials, the use of proper controls, and inclusion of a more complete electrochemical analysis. © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  15. Scaling up microbial fuel cells and other bioelectrochemical systems

    KAUST Repository

    Logan, Bruce E.

    2009-12-15

    Scientific research has advanced on different microbial fuel cell (MFC) technologies in the laboratory at an amazing pace, with power densities having reached over 1 kW/m3 (reactor volume) and to 6.9 W/m2 (anode area) under optimal conditions. The main challenge is to bring these technologies out of the laboratory and engineer practical systems for bioenergy production at larger scales. Recent advances in new types of electrodes, a better understanding of the impact of membranes and separators on performance of these systems, and results from several new pilot-scale tests are all good indicators that commercialization of the technology could be possible within a few years. Some of the newest advances and future challenges are reviewed here with respect to practical applications of these MFCs for renewable energy production and other applications. © 2009 Springer-Verlag.

  16. Scaling up microbial fuel cells and other bioelectrochemical systems

    KAUST Repository

    Logan, Bruce E.

    2009-01-01

    Scientific research has advanced on different microbial fuel cell (MFC) technologies in the laboratory at an amazing pace, with power densities having reached over 1 kW/m3 (reactor volume) and to 6.9 W/m2 (anode area) under optimal conditions. The main challenge is to bring these technologies out of the laboratory and engineer practical systems for bioenergy production at larger scales. Recent advances in new types of electrodes, a better understanding of the impact of membranes and separators on performance of these systems, and results from several new pilot-scale tests are all good indicators that commercialization of the technology could be possible within a few years. Some of the newest advances and future challenges are reviewed here with respect to practical applications of these MFCs for renewable energy production and other applications. © 2009 Springer-Verlag.

  17. Understanding Ammonium Transport in Bioelectrochemical Systems towards its Recovery

    Science.gov (United States)

    Liu, Ying; Qin, Mohan; Luo, Shuai; He, Zhen; Qiao, Rui

    2016-03-01

    We report an integrated experimental and simulation study of ammonia recovery using microbial electrolysis cells (MECs). The transport of various species during the batch-mode operation of an MEC was examined experimentally and the results were used to validate the mathematical model for such an operation. It was found that, while the generated electrical current through the system tends to acidify (or basify) the anolyte (or catholyte), their effects are buffered by a cascade of chemical groups such as the NH3/NH4+ group, leading to relatively stable pH values in both anolyte and catholyte. The transport of NH4+ ions accounts for ~90% of the total current, thus quantitatively confirming that the NH4+ ions serve as effective proton shuttles during MEC operations. Analysis further indicated that, because of the Donnan equilibrium at cation exchange membrane-anolyte/catholyte interfaces, the Na+ ion in the anolyte actually facilitates the transport of NH4+ ions during the early stage of a batch cycle and they compete with the NH4+ ions weakly at later time. These insights, along with a new and simple method for predicting the strength of ammonia diffusion from the catholyte toward the anolyte, will help effective design and operation of bioeletrochemical system-based ammonia recovery systems.

  18. Reference and counter electrode positions affect electrochemical characterization of bioanodes in different bioelectrochemical systems

    KAUST Repository

    Zhang, Fang

    2014-06-16

    The placement of the reference electrode (RE) in various bioelectrochemical systems is often varied to accommodate different reactor configurations. While the effect of the RE placement is well understood from a strictly electrochemistry perspective, there are impacts on exoelectrogenic biofilms in engineered systems that have not been adequately addressed. Varying distances between the working electrode (WE) and the RE, or the RE and the counter electrode (CE) in microbial fuel cells (MFCs) can alter bioanode characteristics. With well-spaced anode and cathode distances in an MFC, increasing the distance between the RE and anode (WE) altered bioanode cyclic voltammograms (CVs) due to the uncompensated ohmic drop. Electrochemical impedance spectra (EIS) also changed with RE distances, resulting in a calculated increase in anode resistance that varied between 17 and 31Ω (-0.2V). While WE potentials could be corrected with ohmic drop compensation during the CV tests, they could not be automatically corrected by the potentiostat in the EIS tests. The electrochemical characteristics of bioanodes were altered by their acclimation to different anode potentials that resulted from varying the distance between the RE and the CE (cathode). These differences were true changes in biofilm characteristics because the CVs were electrochemically independent of conditions resulting from changing CE to RE distances. Placing the RE outside of the current path enabled accurate bioanode characterization using CVs and EIS due to negligible ohmic resistances (0.4Ω). It is therefore concluded for bioelectrochemical systems that when possible, the RE should be placed outside the current path and near the WE, as this will result in more accurate representation of bioanode characteristics. © 2014 Wiley Periodicals, Inc.

  19. Bio-electrochemical system (BES) as an innovative approach for sustainable waste management in petroleum industry.

    Science.gov (United States)

    Srikanth, Sandipam; Kumar, Manoj; Puri, S K

    2018-02-15

    Petroleum industry is one of the largest and fast growing industries due to the ever increasing global energy demands. Petroleum refinery produces huge quantities of wastes like oily sludge, wastewater, volatile organic compounds, waste catalyst, heavy metals, etc., because of its high capacity and continuous operation of many units. Major challenge to this industry is to manage the huge quantities of waste generated from different processes due to the complexity of waste as well as changing stringent environmental regulations. To decrease the energy loss for treatment and also to conserve the energy stored in the chemical bonds of these waste organics, bio-electrochemical system (BES) may be an efficient tool that reduce the economics of waste disposal by transforming the waste into energy pool. The present review discusses about the feasibility of using BES as a potential option for harnessing energy from different waste generated from petroleum refineries. Copyright © 2018. Published by Elsevier Ltd.

  20. Modeling the ion transfer and polarization of ion exchange membranes in bioelectrochemical systems.

    Science.gov (United States)

    Harnisch, Falk; Warmbier, Robert; Schneider, Ralf; Schröder, Uwe

    2009-06-01

    An explicit numerical model for the charge balancing ion transfer across monopolar ion exchange membranes under conditions of bioelectrochemical systems is presented. Diffusion and migration equations have been solved according to the Nernst-Planck Equation and the resulting ion concentrations, pH values and the resistance values of the membrane for different conditions were computed. The modeling results underline the principle limitations of the application of ion exchange membranes in biological fuel cells and electrolyzers, caused by the inherent occurrence of a pH-gradient between anode and cathode compartment, and an increased ohmic membrane resistance at decreasing electrolyte concentrations. Finally, the physical and numerical limitations of the model are discussed.

  1. Microbial electron transport and energy conservation – the foundation for optimizing bioelectrochemical systems

    Science.gov (United States)

    Kracke, Frauke; Vassilev, Igor; Krömer, Jens O.

    2015-01-01

    Microbial electrochemical techniques describe a variety of emerging technologies that use electrode–bacteria interactions for biotechnology applications including the production of electricity, waste and wastewater treatment, bioremediation and the production of valuable products. Central in each application is the ability of the microbial catalyst to interact with external electron acceptors and/or donors and its metabolic properties that enable the combination of electron transport and carbon metabolism. And here also lies the key challenge. A wide range of microbes has been discovered to be able to exchange electrons with solid surfaces or mediators but only a few have been studied in depth. Especially electron transfer mechanisms from cathodes towards the microbial organism are poorly understood but are essential for many applications such as microbial electrosynthesis. We analyze the different electron transport chains that nature offers for organisms such as metal respiring bacteria and acetogens, but also standard biotechnological organisms currently used in bio-production. Special focus lies on the essential connection of redox and energy metabolism, which is often ignored when studying bioelectrochemical systems. The possibility of extracellular electron exchange at different points in each organism is discussed regarding required redox potentials and effect on cellular redox and energy levels. Key compounds such as electron carriers (e.g., cytochromes, ferredoxin, quinones, flavins) are identified and analyzed regarding their possible role in electrode–microbe interactions. This work summarizes our current knowledge on electron transport processes and uses a theoretical approach to predict the impact of different modes of transfer on the energy metabolism. As such it adds an important piece of fundamental understanding of microbial electron transport possibilities to the research community and will help to optimize and advance bioelectrochemical

  2. Alternate charging and discharging of capacitor to enhance the electron production of bioelectrochemical systems.

    Science.gov (United States)

    Liang, Peng; Wu, Wenlong; Wei, Jincheng; Yuan, Lulu; Xia, Xue; Huang, Xia

    2011-08-01

    A bioelectrochemical system (BES) can be operated in both "microbial fuel cell" (MFC) and "microbial electrolysis cell" (MEC) modes, in which power is delivered and invested respectively. To enhance the electric current production, a BES was operated in MFC mode first and a capacitor was used to collect power from the system. Then the charged capacitor discharged electrons to the system itself, switching into MEC mode. This alternate charging and discharging (ACD) mode helped the system produce 22-32% higher average current compared to an intermittent charging (IC) mode, in which the capacitor was first charged from an MFC and then discharged to a resistor, at 21.6 Ω external resistance, 3.3 F capacitance and 300 mV charging voltage. The effects of external resistance, capacitance and charging voltage on average current were studied. The average current reduced as the external resistance and charging voltage increased and was slightly affected by the capacitance. Acquisition of higher average current in the ACD mode was attributed to the shorter discharging time compared to the charging time, as well as a higher anode potential caused by discharging the capacitor. Results from circuit analysis and quantitatively calculation were consistent with the experimental observations.

  3. Pulse electromagnetic fields enhance extracellular electron transfer in magnetic bioelectrochemical systems.

    Science.gov (United States)

    Zhou, Huihui; Liu, Bingfeng; Wang, Qisong; Sun, Jianmin; Xie, Guojun; Ren, Nanqi; Ren, Zhiyong Jason; Xing, Defeng

    2017-01-01

    Microbial extracellular electron transfer (EET) is essential in driving the microbial interspecies interaction and redox reactions in bioelectrochemical systems (BESs). Magnetite (Fe 3 O 4 ) and magnetic fields (MFs) were recently reported to promote microbial EET, but the mechanisms of MFs stimulation of EET and current generation in BESs are not known. This study investigates the behavior of current generation and EET in a state-of-the-art pulse electromagnetic field (PEMF)-assisted magnetic BES (PEMF-MBES), which was equipped with magnetic carbon particle (Fe 3 O 4 @N-mC)-coated electrodes. Illumina Miseq sequencing of 16S rRNA gene amplicons was also conducted to reveal the changes of microbial communities and interactions on the anode in response to magnetic field. PEMF had significant influences on current generation. When reactors were operated in microbial fuel cell (MFC) mode with pulse electromagnetic field (PEMF-MMFCs), power densities increased by 25.3-36.0% compared with no PEMF control MFCs (PEMF-OFF-MMFCs). More interestingly, when PEMF was removed, the power density dropped by 25.7%, while when PEMF was reintroduced, the value was restored to the previous level. Illumina sequencing of 16S rRNA gene amplicon and principal component analysis (PCA) based on operational taxonomic units (OTUs) indicate that PEMFs led to the shifts in microbial community and changes in species evenness that decreased biofilm microbial diversity. Geobacter spp. were found dominant in all anode biofilms, but the relative abundance in PEMF-MMFCs (86.1-90.0%) was higher than in PEMF-OFF-MMFCs (82.5-82.7%), indicating that the magnetic field enriched Geobacter on the anode. The current generation of Geobacter -inoculated microbial electrolysis cells (MECs) presented the same change regularity, the accordingly increase or decrease corresponding with switch of PEMF, which confirmed the reversible stimulation of PEMFs on microbial electron transfer. The pulse electromagnetic

  4. When Bioelectrochemical Systems Meet Forward Osmosis: Accomplishing Wastewater Treatment and Reuse through Synergy

    Directory of Open Access Journals (Sweden)

    Yaobin Lu

    2014-12-01

    Full Text Available Bioelectrochemical systems (BES and forward osmosis (FO are two emerging technologies with great potential for energy-efficient water/wastewater treatment. BES takes advantage of microbial interaction with a solid electron acceptor/donor to accomplish bioenergy recovery from organic compounds, and FO can extract high-quality water driven by an osmotic pressure. The strong synergy between those two technologies may complement each other and collaboratively address water-energy nexus. FO can assist BES with achieving water recovery (for future reuse, enhancing electricity generation, and supplying energy for accomplishing the cathode reactions; while BES may help FO with degrading organic contaminants, providing sustainable draw solute, and stabilizing water flux. This work has reviewed the recent development that focuses on the synergy between BES and FO, analyzed the advantages of each combination, and provided perspectives for future research. The findings encourage further investigation and development for efficient coordination between BES and FO towards an integrated system for wastewater treatment and reuse.

  5. Spatial variation of electrode position in bioelectrochemical treatment system: Design consideration for azo dye remediation.

    Science.gov (United States)

    Yeruva, Dileep Kumar; Shanthi Sravan, J; Butti, Sai Kishore; Annie Modestra, J; Venkata Mohan, S

    2018-05-01

    In the present study, three bio-electrochemical treatment systems (BET) were designed with variations in cathode electrode placement [air exposed (BET1), partially submerged (BET2) and fully submerged (BET3)] to evaluate azo-dye based wastewater treatment at three dye loading concentrations (50, 250 and 500 mg L -1 ). Highest dye decolorization (94.5 ± 0.4%) and COD removal (62.2 ± 0.8%) efficiencies were observed in BET3 (fully submerged electrodes) followed by BET1 and BET2, while bioelectrogenic activity was highest in BET1 followed by BET2 and BET3. It was observed that competition among electron acceptors (electrode, dye molecules and intermediates) critically regulated the fate of bio-electrogenesis to be higher in BET1 and dye removal higher in BET3. Maximum half-cell potentials in BET3 depict higher electron acceptance by electrodes utilized for dye degradation. Study infers that spatial positioning of electrodes in BET3 is more suitable towards dye remediation, which can be considered for scaling-up/designing a treatment plant for large-scale industrial applications. Copyright © 2018 Elsevier Ltd. All rights reserved.

  6. Copper Recovery from Polluted Soils Using Acidic Washing and Bioelectrochemical Systems

    Directory of Open Access Journals (Sweden)

    Karin Karlfeldt Fedje

    2015-07-01

    Full Text Available Excavation followed by landfilling is the most common method for treating soils contaminated by metals. However, as this solution is not sustainable, alternative techniques are required. Chemical soil washing is one such alternative. The aim of this experimental lab-scale study is to develop a remediation and metal recovery method for Cu contaminated sites. The method is based on the washing of soil or ash (combusted soil/bark with acidic waste liquids followed by electrolytic Cu recovery by means of bioelectrochemical systems (BES. The results demonstrate that a one- or two-step acidic leaching process followed by water washing removes >80 wt. % of the Cu. Copper with 99.7–99.9 wt. % purity was recovered from the acidic leachates using BES. In all experiments, electrical power was generated during the reduction of Cu. This clearly indicates that Cu can also be recovered from dilute solutions. Additionally, the method has the potential to wash co-pollutants such as polycyclic aromatic hydrocarbons (PAHs and oxy-PAHs.

  7. Low Substrate Loading Limits Methanogenesis and Leads to High Coulombic Efficiency in Bioelectrochemical Systems

    Directory of Open Access Journals (Sweden)

    Tom H. J. A. Sleutels

    2016-01-01

    Full Text Available A crucial aspect for the application of bioelectrochemical systems (BESs as a wastewater treatment technology is the efficient oxidation of complex substrates by the bioanode, which is reflected in high Coulombic efficiency (CE. To achieve high CE, it is essential to give a competitive advantage to electrogens over methanogens. Factors that affect CE in bioanodes are, amongst others, the type of wastewater, anode potential, substrate concentration and pH. In this paper, we focus on acetate as a substrate and analyze the competition between methanogens and electrogens from a thermodynamic and kinetic point of view. We reviewed experimental data from earlier studies and propose that low substrate loading in combination with a sufficiently high anode overpotential plays a key-role in achieving high CE. Low substrate loading is a proven strategy against methanogenic activity in large-scale reactors for sulfate reduction. The combination of low substrate loading with sufficiently high overpotential is essential because it results in favorable growth kinetics of electrogens compared to methanogens. To achieve high current density in combination with low substrate concentrations, it is essential to have a high specific anode surface area. New reactor designs with these features are essential for BESs to be successful in wastewater treatment in the future.

  8. Low Substrate Loading Limits Methanogenesis and Leads to High Coulombic Efficiency in Bioelectrochemical Systems

    Science.gov (United States)

    Sleutels, Tom H. J. A.; Molenaar, Sam D.; Heijne, Annemiek Ter; Buisman, Cees J. N.

    2016-01-01

    A crucial aspect for the application of bioelectrochemical systems (BESs) as a wastewater treatment technology is the efficient oxidation of complex substrates by the bioanode, which is reflected in high Coulombic efficiency (CE). To achieve high CE, it is essential to give a competitive advantage to electrogens over methanogens. Factors that affect CE in bioanodes are, amongst others, the type of wastewater, anode potential, substrate concentration and pH. In this paper, we focus on acetate as a substrate and analyze the competition between methanogens and electrogens from a thermodynamic and kinetic point of view. We reviewed experimental data from earlier studies and propose that low substrate loading in combination with a sufficiently high anode overpotential plays a key-role in achieving high CE. Low substrate loading is a proven strategy against methanogenic activity in large-scale reactors for sulfate reduction. The combination of low substrate loading with sufficiently high overpotential is essential because it results in favorable growth kinetics of electrogens compared to methanogens. To achieve high current density in combination with low substrate concentrations, it is essential to have a high specific anode surface area. New reactor designs with these features are essential for BESs to be successful in wastewater treatment in the future. PMID:27681899

  9. In situ Biofilm Quantification in Bioelectrochemical Systems by using Optical Coherence Tomography.

    Science.gov (United States)

    Molenaar, Sam D; Sleutels, Tom; Pereira, Joao; Iorio, Matteo; Borsje, Casper; Zamudio, Julian A; Fabregat-Santiago, Francisco; Buisman, Cees J N; Ter Heijne, Annemiek

    2018-04-25

    Detailed studies of microbial growth in bioelectrochemical systems (BESs) are required for their suitable design and operation. Here, we report the use of optical coherence tomography (OCT) as a tool for in situ and noninvasive quantification of biofilm growth on electrodes (bioanodes). An experimental platform is designed and described in which transparent electrodes are used to allow real-time, 3D biofilm imaging. The accuracy and precision of the developed method is assessed by relating the OCT results to well-established standards for biofilm quantification (chemical oxygen demand (COD) and total N content) and show high correspondence to these standards. Biofilm thickness observed by OCT ranged between 3 and 90 μm for experimental durations ranging from 1 to 24 days. This translated to growth yields between 38 and 42 mgCODbiomass  gCODacetate -1 at an anode potential of -0.35 V versus Ag/AgCl. Time-lapse observations of an experimental run performed in duplicate show high reproducibility in obtained microbial growth yield by the developed method. As such, we identify OCT as a powerful tool for conducting in-depth characterizations of microbial growth dynamics in BESs. Additionally, the presented platform allows concomitant application of this method with various optical and electrochemical techniques. © 2018 The Authors. Published by Wiley-VCH Verlag GmbH & Co. KGaA.

  10. Heat-treated stainless steel felt as scalable anode material for bioelectrochemical systems.

    Science.gov (United States)

    Guo, Kun; Soeriyadi, Alexander H; Feng, Huajun; Prévoteau, Antonin; Patil, Sunil A; Gooding, J Justin; Rabaey, Korneel

    2015-11-01

    This work reports a simple and scalable method to convert stainless steel (SS) felt into an effective anode for bioelectrochemical systems (BESs) by means of heat treatment. X-ray photoelectron spectroscopy and cyclic voltammetry elucidated that the heat treatment generated an iron oxide rich layer on the SS felt surface. The iron oxide layer dramatically enhanced the electroactive biofilm formation on SS felt surface in BESs. Consequently, the sustained current densities achieved on the treated electrodes (1 cm(2)) were around 1.5±0.13 mA/cm(2), which was seven times higher than the untreated electrodes (0.22±0.04 mA/cm(2)). To test the scalability of this material, the heat-treated SS felt was scaled up to 150 cm(2) and similar current density (1.5 mA/cm(2)) was achieved on the larger electrode. The low cost, straightforwardness of the treatment, high conductivity and high bioelectrocatalytic performance make heat-treated SS felt a scalable anodic material for BESs. Copyright © 2015 Elsevier Ltd. All rights reserved.

  11. Pyrolytic carbon-coated stainless steel felt as a high-performance anode for bioelectrochemical systems.

    Science.gov (United States)

    Guo, Kun; Hidalgo, Diana; Tommasi, Tonia; Rabaey, Korneel

    2016-07-01

    Scale up of bioelectrochemical systems (BESs) requires highly conductive, biocompatible and stable electrodes. Here we present pyrolytic carbon-coated stainless steel felt (C-SS felt) as a high-performance and scalable anode. The electrode is created by generating a carbon layer on stainless steel felt (SS felt) via a multi-step deposition process involving α-d-glucose impregnation, caramelization, and pyrolysis. Physicochemical characterizations of the surface elucidate that a thin (20±5μm) and homogenous layer of polycrystalline graphitic carbon was obtained on SS felt surface after modification. The carbon coating significantly increases the biocompatibility, enabling robust electroactive biofilm formation. The C-SS felt electrodes reach current densities (jmax) of 3.65±0.14mA/cm(2) within 7days of operation, which is 11 times higher than plain SS felt electrodes (0.30±0.04mA/cm(2)). The excellent biocompatibility, high specific surface area, high conductivity, good mechanical strength, and low cost make C-SS felt a promising electrode for BESs. Copyright © 2016 Elsevier Ltd. All rights reserved.

  12. Low Substrate Loading Limits Methanogenesis and Leads to High Coulombic Efficiency in Bioelectrochemical Systems.

    Science.gov (United States)

    Sleutels, Tom H J A; Molenaar, Sam D; Heijne, Annemiek Ter; Buisman, Cees J N

    2016-01-05

    A crucial aspect for the application of bioelectrochemical systems (BESs) as a wastewater treatment technology is the efficient oxidation of complex substrates by the bioanode, which is reflected in high Coulombic efficiency (CE). To achieve high CE, it is essential to give a competitive advantage to electrogens over methanogens. Factors that affect CE in bioanodes are, amongst others, the type of wastewater, anode potential, substrate concentration and pH. In this paper, we focus on acetate as a substrate and analyze the competition between methanogens and electrogens from a thermodynamic and kinetic point of view. We reviewed experimental data from earlier studies and propose that low substrate loading in combination with a sufficiently high anode overpotential plays a key-role in achieving high CE. Low substrate loading is a proven strategy against methanogenic activity in large-scale reactors for sulfate reduction. The combination of low substrate loading with sufficiently high overpotential is essential because it results in favorable growth kinetics of electrogens compared to methanogens. To achieve high current density in combination with low substrate concentrations, it is essential to have a high specific anode surface area. New reactor designs with these features are essential for BESs to be successful in wastewater treatment in the future.

  13. Geophysical Monitoring of Hydrocarbon-Contaminated Soils Remediated with a Bioelectrochemical System.

    Science.gov (United States)

    Mao, Deqiang; Lu, Lu; Revil, André; Zuo, Yi; Hinton, John; Ren, Zhiyong Jason

    2016-08-02

    Efficient noninvasive techniques are desired for monitoring the remediation process of contaminated soils. We applied the direct current resistivity technique to image conductivity changes in sandbox experiments where two sandy and clayey soils were initially contaminated with diesel hydrocarbon. The experiments were conducted over a 230 day period. The removal of hydrocarbon was enhanced by a bioelectrochemical system (BES) and the electrical potentials of the BES reactors were also monitored during the course of the experiment. We found that the variation in electrical conductivity shown in the tomograms correlate well with diesel removal from the sandy soil, but this is not the case with the clayey soil. The clayey soil is characterized by a larger specific surface area and therefore a larger surface conductivity. In sandy soil, the removal of the diesel and products from degradation leads to an increase in electrical conductivity during the first 69 days. This is expected since diesel is electrically insulating. For both soils, the activity of BES reactors is moderately imaged by the inverted conductivity tomogram of the reactor. An increase in current production by electrochemically active bacteria activity corresponds to an increase in conductivity of the reactor.

  14. Enhanced bioremediation of hydrocarbon-contaminated soil using pilot-scale bioelectrochemical systems.

    Science.gov (United States)

    Lu, Lu; Yazdi, Hadi; Jin, Song; Zuo, Yi; Fallgren, Paul H; Ren, Zhiyong Jason

    2014-06-15

    Two column-type bioelectrochemical system (BES) modules were installed into a 50-L pilot scale reactor packed with diesel-contaminated soils to investigate the enhancement of passive biodegradation of petroleum compounds. By using low cost electrodes such as biochar and graphite granule as non-exhaustible solid-state electron acceptors, the results show that 82.1-89.7% of the total petroleum hydrocarbon (TPH) was degraded after 120 days across 1-34 cm radius of influence (ROI) from the modules. This represents a maximum of 241% increase of biodegradation compared to a baseline control reactor. The current production in the BESs correlated with the TPH removal, reaching the maximum output of 70.4 ± 0.2 mA/m(2). The maximum ROI of the BES, deducting influence from the baseline natural attenuation, was estimated to be more than 90 cm beyond the edge of the reactor (34 cm), and exceed 300 cm should a non-degradation baseline be used. The ratio of the projected ROI to the radius of BES (ROB) module was 11-12. The results suggest that this BES can serve as an innovative and sustainable technology for enhanced in situ bioremediation of petroleum hydrocarbons in large field scale, with additional benefits of electricity production and being integrated into existing field infrastructures. Copyright © 2014 Elsevier B.V. All rights reserved.

  15. Simultaneous removal of organic matter and salt ions from saline wastewater in bioelectrochemical systems

    KAUST Repository

    Kim, Younggy

    2013-01-01

    A new bioelectrochemical system is proposed for simultaneous removal of salinity and organic matter. In this process, exoelectrogenic microorganisms oxidize organic matter and transfer electrons to the anode, hydrogen is evolved at the cathode by supplying additional voltage, and salt is removed from the wastewater due to the electric potential generated and the use of two ion-exchange membranes. Salinity removal (initial conductivity ~40mS/cm) increased from 21 to 84% by increasing the substrate (sodium acetate) from 2 to 8g/L. A total of 72-94% of the chemical oxygen demand was degraded in the anode and cathode chambers, with 1-4% left in the anode chamber and the balance lost through the anion-exchange membrane into the concentrate waste chamber. The maximum hydrogen production rate was 3.6m3-H2/m3-electrolyte per day at an applied potential of 1.2V. The Coulombic efficiency was ~100%, while the cathode recovery varied from 57 to 100%, depending on the extent of methanogenesis. Exoelectrogenic microbes generated high current densities (7.8mA/cm2) at ≤36g/L of total dissolved solids, but >41g/L eliminated current. These results provide a new method for achieving simultaneous removal of salinity and organic matter from a saline wastewater with H2 production. © 2012 Elsevier B.V.

  16. Mathematical modeling based evaluation and simulation of boron removal in bioelectrochemical systems

    Energy Technology Data Exchange (ETDEWEB)

    Ping, Qingyun [Department of Civil and Environmental Engineering, Virginia Polytechnic Institute and State University, Blacksburg, VA 24061 (United States); Abu-Reesh, Ibrahim M. [Department of Chemical Engineering, College of Engineering, Qatar University, P.O. Box 2713, Doha (Qatar); He, Zhen, E-mail: zhenhe@vt.edu [Department of Civil and Environmental Engineering, Virginia Polytechnic Institute and State University, Blacksburg, VA 24061 (United States)

    2016-11-01

    Boron removal is an arising issue in desalination plants due to boron's toxicity. As an emerging treatment concept, bioelectrochemical systems (BES) can achieve potentially cost-effective boron removal by taking advantage of cathodic-produced alkali. Prior studies have demonstrated successful removal of boron in microbial desalination cells (MDCs) and microbial fuel cells (MFCs), both of which are representative BES. Herein, mathematical models were developed to further evaluate boron removal by different BES and understand the key operating factors. The models delivered very good prediction of the boron concentration in the MDC integrated with Donnan Dialysis (DD) system with the lowest relative root-mean-square error (RMSE) of 0.00%; the predication of the MFC performance generated the highest RMSE of 18.55%. The model results of salt concentration, solution pH, and current generation were well fitted with experimental data for RMSE values mostly below 10%. The long term simulation of the MDC-DD system suggests that the accumulation of salt in the catholyte/stripping solution could have a positive impact on the removal of boron due to osmosis-driven convection. The current generation in the MDC may have little influence on the boron removal, while in the MFC the current-driven electromigration can contribute up to 40% of boron removal. Osmosis-induced convection transport of boron could be the major driving force for boron removal to a low level < 2 mg L{sup −} {sup 1}. The ratio between the anolyte and the catholyte flow rates should be kept > 22.2 in order to avoid boron accumulation in the anolyte effluent. - Highlights: • Mathematical models are developed to understand boron removal in BES. • Boron removal can be driven by electromigration induced by current generation. • Diffusion induced by a salt concentration gradient also contributes to boron removal. • Osmosis and current driven convection transport play diverse roles in different BES.

  17. Mathematical modeling based evaluation and simulation of boron removal in bioelectrochemical systems.

    Science.gov (United States)

    Ping, Qingyun; Abu-Reesh, Ibrahim M; He, Zhen

    2016-11-01

    Boron removal is an arising issue in desalination plants due to boron's toxicity. As an emerging treatment concept, bioelectrochemical systems (BES) can achieve potentially cost-effective boron removal by taking advantage of cathodic-produced alkali. Prior studies have demonstrated successful removal of boron in microbial desalination cells (MDCs) and microbial fuel cells (MFCs), both of which are representative BES. Herein, mathematical models were developed to further evaluate boron removal by different BES and understand the key operating factors. The models delivered very good prediction of the boron concentration in the MDC integrated with Donnan Dialysis (DD) system with the lowest relative root-mean-square error (RMSE) of 0.00%; the predication of the MFC performance generated the highest RMSE of 18.55%. The model results of salt concentration, solution pH, and current generation were well fitted with experimental data for RMSE values mostly below 10%. The long term simulation of the MDC-DD system suggests that the accumulation of salt in the catholyte/stripping solution could have a positive impact on the removal of boron due to osmosis-driven convection. The current generation in the MDC may have little influence on the boron removal, while in the MFC the current-driven electromigration can contribute up to 40% of boron removal. Osmosis-induced convection transport of boron could be the major driving force for boron removal to a low level 22.2 in order to avoid boron accumulation in the anolyte effluent. Copyright © 2016 Elsevier B.V. All rights reserved.

  18. (Bio)electrochemical ammonia recovery

    NARCIS (Netherlands)

    Kuntke, P.; Sleutels, T.H.J.A.; Rodríguez Arredondo, M.; Georg, S.; Barbosa, S.G.; Heijne, Ter A.; Hamelers, Hubertus V.M.; Buisman, C.J.N.

    2018-01-01

    In recent years, (bio)electrochemical systems (B)ES have emerged as an energy efficient alternative for the recovery of TAN (total ammonia nitrogen, including ammonia and ammonium) from wastewater. In these systems, TAN is removed or concentrated from the wastewater under the influence of an

  19. Sustainable and Efficient Pathways for Bioenergy Recovery from Low-Value Process Streams via Bioelectrochemical Systems in Biorefineries

    Directory of Open Access Journals (Sweden)

    Abhijeet P. Borole

    2015-08-01

    Full Text Available Conversion of biomass into bioenergy is possible via multiple pathways resulting in the production of biofuels, bioproducts, and biopower. Efficient and sustainable conversion of biomass, however, requires consideration of many environmental and societal parameters in order to minimize negative impacts. Integration of multiple conversion technologies and inclusion of upcoming alternatives, such as bioelectrochemical systems, can minimize these impacts via production of hydrogen, electricity or other forms of energy from the low value streams and improve conservation of resources, such as water and nutrients via recycle and reuse. This report outlines alternate pathways integrating microbial electrolysis in biorefinery schemes to improve energy efficiency, while evaluating environmental sustainability parameters.

  20. Removal of heavy metals from fly ash leachate using combined bioelectrochemical systems and electrolysis

    International Nuclear Information System (INIS)

    Tao, Hu-Chun; Lei, Tao; Shi, Gang; Sun, Xiao-Nan; Wei, Xue-Yan; Zhang, Li-Juan; Wu, Wei-Min

    2014-01-01

    Highlights: • Heavy metals removal from MSWI fly ash with BES and electrolysis was confirmed. • 98.5% of Cu(II), 95.4% of Zn(II) and 98.1% of Pb(II) removal were achieved in reactors. • BESs can remove some heavy metals in fly ash with energy saving. -- Abstract: Based on environmental and energetic analysis, a novel combined approach using bioelectrochemical systems (BES) followed by electrolysis reactors (ER) was tested for heavy metals removal from fly ash leachate, which contained high detectable levels of Zn, Pb and Cu according to X-ray diffraction analysis. Acetic acid was used as the fly ash leaching agent and tested under various leaching conditions. A favorable condition for the leaching process was identified to be liquid/solid ratio of 14:1 (w/w) and leaching duration 10 h at initial pH 1.0. It was confirmed that the removal of heavy metals from fly ash leachate with the combination of BESs and ER is feasible. The metal removal efficiency was achieved at 98.5%, 95.4% and 98.1% for Cu(II), Zn(II), and Pb(II), respectively. Results of scanning electron microscopy (SEM) and energy-dispersive X-ray spectroscopy (EDS) indicated that Cu(II) was reduced and recovered mainly as metal Cu on cathodes related to power production, while Zn(II) and Pb(II) were not spontaneously reduced in BESs without applied voltage and basically electrolyzed in the electrolysis reactors

  1. Evaluation of energy consumption of treating nitrate-contaminated groundwater by bioelectrochemical systems.

    Science.gov (United States)

    Cecconet, Daniele; Zou, Shiqiang; Capodaglio, Andrea G; He, Zhen

    2018-09-15

    Nitrate contamination of groundwater is a mounting concern for drinking water production due to its healthy and ecological effects. Bioelectrochemical systems (BES) are a promising method for energy efficient nitrate removal, but its energy consumption has not been well understood. Herein, we conducted a preliminary analysis of energy consumption based on both literature information and multiple assumptions. Four scenarios were created for the purpose of analysis based on two treatment approaches, microbial fuel cells (MFCs) and controlled biocathodic denitrification (CBD), under either in situ or ex situ deployment. The results show a specific energy consumption based on the mass of NO 3 - -N removed (SEC N ) of 0.341 and 1.602 kWh kg NO 3 - -N -1 obtained from in situ and ex situ treatments with MFCs, respectively; the main contributor was the extraction of the anolyte (100%) in the former and pumping the groundwater (74.8%) for the latter. In the case of CBD treatment, the energy consumption by power supply outcompeted all the other energy items (over 85% in all cases), and a total SEC N of 19.028 and 10.003 kWh kg NO 3 - -N -1 were obtained for in situ and ex situ treatments, respectively. The increase in the water table depth (from 10 to 30 m) and the decrease of the nitrate concentration (from 25 to 15 mg NO 3 - -N) would lead to a rise in energy consumption in the ex situ treatment. Although some data might be premature due to the lack of sufficient information in available literature, the results could provide an initial picture of energy consumption by BES-based groundwater treatment and encourage further thinking and analysis of energy consumption (and production). Copyright © 2018 Elsevier B.V. All rights reserved.

  2. Using sewage sludge pyrolytic gas to modify titanium alloy to obtain high-performance anodes in bio-electrochemical systems

    Science.gov (United States)

    Gu, Yuan; Ying, Kang; Shen, Dongsheng; Huang, Lijie; Ying, Xianbin; Huang, Haoqian; Cheng, Kun; Chen, Jiazheng; Zhou, Yuyang; Chen, Ting; Feng, Huajun

    2017-12-01

    Titanium is under consideration as a potential stable bio-anode because of its high conductivity, suitable mechanical properties, and electrochemical inertness in the operating potential window of bio-electrochemical systems; however, its application is limited by its poor electron-transfer capacity with electroactive bacteria and weak ability to form biofilms on its hydrophobic surface. This study reports an effective and low-cost way to convert a hydrophobic titanium alloy surface into a hydrophilic surface that can be used as a bio-electrode with higher electron-transfer rates. Pyrolytic gas of sewage sludge is used to modify the titanium alloy. The current generation, anodic biofilm formation surface, and hydrophobicity are systematically investigated by comparing bare electrodes with three modified electrodes. Maximum current density (15.80 A/m2), achieved using a modified electrode, is 316-fold higher than that of the bare titanium alloy electrode (0.05 A/m2) and that achieved by titanium alloy electrodes modified by other methods (12.70 A/m2). The pyrolytic gas-modified titanium alloy electrode can be used as a high-performance and scalable bio-anode for bio-electrochemical systems because of its high electron-transfer rates, hydrophilic nature, and ability to achieve high current density.

  3. A bio-electrochemical system for removing inhibitors of anaerobic digestion processes from anaerobic reactors

    DEFF Research Database (Denmark)

    2014-01-01

    Inhibition of anaerobic digestion process by high level of ammonia (NH4 +/I\\IH3) is the most serious problem existing in biogas plants. No viable/applicable method to overcome this problem has been found up to now. This invention proposes an innovative submersible bio-electrochemical membrane...... reactor to recover ammonia from anaerobic digestion reactor, and thereby alleviate or counteract ammonia inhibition and enhance the conversion of ammonia-rich wastes to biogas. The invention may further reduce overall cost, giving synergistic advantages for both ammonia recycling and biogas plants...... by recovering acid (e.g., H2SO4, HCI), that can be used to treat the recovered ammonia....

  4. Biotransformation of carbon dioxide in bioelectrochemical systems: State of the art and future prospects

    Science.gov (United States)

    Bajracharya, Suman; Srikanth, Sandipam; Mohanakrishna, Gunda; Zacharia, Renju; Strik, David PBTB; Pant, Deepak

    2017-07-01

    Carbon dioxide (CO2) utilization/recycling for the production of chemicals and gaseous/liquid energy-carriers is a way to moderate the rising CO2 in the atmosphere. One of the possible solutions for the CO2 sequestration is the electrochemical reduction of this stable molecule to useful fuel/products. Nevertheless, the surface chemistry of CO2 reduction is a challenge due to the presence of large energy barriers, requiring noticeable catalysis. The recent approach of microbial electrocatalysis of CO2 reduction has promising prospects to reduce the carbon level sustainably, taking full advantage of CO2-derived chemical commodities. We review the currently investigated bioelectrochemical approaches that could possibly be implemented to enable the handling of CO2 emissions. This review covers the most recent advances in the bioelectrochemical approaches of CO2 transformations in terms of biocatalysts development and process design. Furthermore, the extensive research on carbon fixation and conversion to different value added chemicals is reviewed. The review concludes by detailing the key challenges and future prospects that could enable economically feasible microbial electrosynthesis technology.

  5. Effects of process operating conditions on the autotrophic denitrification of nitrate-contaminated groundwater using bioelectrochemical systems.

    Science.gov (United States)

    Cecconet, D; Devecseri, M; Callegari, A; Capodaglio, A G

    2018-02-01

    Nitrates have been detected in groundwater worldwide, and their presence can lead to serious groundwater use limitations, especially because of potential health problems. Amongst different options for their removal, bioelectrochemical systems (BESs) have achieved promising results; in particular, attention has raised on BES-driven autotrophic denitrification processes. In this work, the performance of a microbial electrolysis cell (MEC) for groundwater autotrophic denitrification, is assessed in different conditions of nitrate load, hydraulic retention time (HRT) and process configuration. The system obtained almost complete nitrate removal under all conditions, while nitrite accumulation was recorded at nitrate loads higher than 100mgNO 3 - L -1 . The MEC system achieved, in different tests, a maximum nitrate removal rate of 62.15±3.04gNO 3 - -Nm -3 d -1 , while the highest TN removal rate observed was 35.37±1.18gTNm -3 d -1 . Characteristic of this process is a particularly low (in comparison with other reported works) energy consumption: 3.17·10 -3 ±2.26·10 -3 kWh/gNO 3 - N removed and 7.52·10 -2 ±3.58·10 -2 kWhm -3 treated. The anolyte configuration in closed loop allowed the process to use less clean water, while guaranteeing identical performances as in other conventional configurations. Copyright © 2017 Elsevier B.V. All rights reserved.

  6. A Portable Low-Power Acquisition System with a Urease Bioelectrochemical Sensor for Potentiometric Detection of Urea Concentrations.

    Science.gov (United States)

    Ma, Wei-Jhe; Luo, Ching-Hsing; Lin, Jiun-Ling; Chou, Sin-Houng; Chen, Ping-Hung; Syu, Mei-Jywan; Kuo, Shin-Hung; Lai, Shin-Chi

    2016-04-02

    This paper presents a portable low-power battery-driven bioelectrochemical signal acquisition system for urea detection. The proposed design has several advantages, including high performance, low cost, low-power consumption, and high portability. A LT1789-1 low-supply-voltage instrumentation amplifier (IA) was used to measure and amplify the open-circuit potential (OCP) between the working and reference electrodes. An MSP430 micro-controller was programmed to process and transduce the signals to the custom-developed software by ZigBee RF module in wireless mode and UART in able mode. The immobilized urease sensor was prepared by embedding urease into the polymer (aniline-co-o-phenylenediamine) polymeric matrix and then coating/depositing it onto a MEMS-fabricated Au working electrode. The linear correlation established between the urea concentration and the potentiometric change is in the urea concentrations range of 3.16 × 10(-4) to 3.16 × 10(-2) M with a sensitivity of 31.12 mV/log [M] and a precision of 0.995 (R² = 0.995). This portable device not only detects urea concentrations, but can also operate continuously with a 3.7 V rechargeab-le lithium-ion battery (500 mA·h) for at least four days. Accordingly, its use is feasible and even promising for home-care applications.

  7. Acceleration of organic removal and electricity generation from dewatered oily sludge in a bioelectrochemical system by rhamnolipid addition.

    Science.gov (United States)

    Zhang, Yunshu; Zhao, Qingliang; Jiang, Junqiu; Wang, Kun; Wei, Liangliang; Ding, Jing; Yu, Hang

    2017-11-01

    Conversion of biomass energy of dewatered oily sludge to electricity is the rate-limiting process in bioelectrochemical system (BES). In this study, 2mgg -1 rhamnolipids were added to dewatered oily sludge, resulting in a significant enhancement in maximum power density from 3.84±0.37 to 8.63±0.81Wm -3 , together with an increase in total organic carbon (TOC) and total petroleum hydrocarbon (TPH) removal from 24.52±4.30 to 36.15±2.79mgg -1 and 29.51±3.30 to 39.80±2.47mgg -1 , respectively. Rhamnolipids can also enhance the solubilization and promote the hydrolysis of dewatered oily sludge with increases in SOCD from 14.93±2.44 to 18.40±0.08mgg -1 and VFAs from 1.02±0.07 to 1.39±0.12mgg -1 . Furthermore, bacteria related to substrate degradation were predominant in dewatered oily sludge, and bacteria related to the sulfate/sulfide cycle were significantly enriched by rhamnolipid addition. Copyright © 2017 Elsevier Ltd. All rights reserved.

  8. A Portable Low-Power Acquisition System with a Urease Bioelectrochemical Sensor for Potentiometric Detection of Urea Concentrations

    Directory of Open Access Journals (Sweden)

    Wei-Jhe Ma

    2016-04-01

    Full Text Available This paper presents a portable low-power battery-driven bioelectrochemical signal acquisition system for urea detection. The proposed design has several advantages, including high performance, low cost, low-power consumption, and high portability. A LT1789-1 low-supply-voltage instrumentation amplifier (IA was used to measure and amplify the open-circuit potential (OCP between the working and reference electrodes. An MSP430 micro-controller was programmed to process and transduce the signals to the custom-developed software by ZigBee RF module in wireless mode and UART in able mode. The immobilized urease sensor was prepared by embedding urease into the polymer (aniline-co-o-phenylenediamine polymeric matrix and then coating/depositing it onto a MEMS-fabricated Au working electrode. The linear correlation established between the urea concentration and the potentiometric change is in the urea concentrations range of 3.16 × 10−4 to 3.16 × 10−2 M with a sensitivity of 31.12 mV/log [M] and a precision of 0.995 (R2 = 0.995. This portable device not only detects urea concentrations, but can also operate continuously with a 3.7 V rechargeab-le lithium-ion battery (500 mA·h for at least four days. Accordingly, its use is feasible and even promising for home-care applications.

  9. A Portable Low-Power Acquisition System with a Urease Bioelectrochemical Sensor for Potentiometric Detection of Urea Concentrations

    Science.gov (United States)

    Ma, Wei-Jhe; Luo, Ching-Hsing; Lin, Jiun-Ling; Chou, Sin-Houng; Chen, Ping-Hung; Syu, Mei-Jywan; Kuo, Shin-Hung; Lai, Shin-Chi

    2016-01-01

    This paper presents a portable low-power battery-driven bioelectrochemical signal acquisition system for urea detection. The proposed design has several advantages, including high performance, low cost, low-power consumption, and high portability. A LT1789-1 low-supply-voltage instrumentation amplifier (IA) was used to measure and amplify the open-circuit potential (OCP) between the working and reference electrodes. An MSP430 micro-controller was programmed to process and transduce the signals to the custom-developed software by ZigBee RF module in wireless mode and UART in able mode. The immobilized urease sensor was prepared by embedding urease into the polymer (aniline-co-o-phenylenediamine) polymeric matrix and then coating/depositing it onto a MEMS-fabricated Au working electrode. The linear correlation established between the urea concentration and the potentiometric change is in the urea concentrations range of 3.16 × 10−4 to 3.16 × 10−2 M with a sensitivity of 31.12 mV/log [M] and a precision of 0.995 (R2 = 0.995). This portable device not only detects urea concentrations, but can also operate continuously with a 3.7 V rechargeab-le lithium-ion battery (500 mA·h) for at least four days. Accordingly, its use is feasible and even promising for home-care applications. PMID:27049390

  10. Efficient azo dye decolorization in a continuous stirred tank reactor (CSTR) with built-in bioelectrochemical system.

    Science.gov (United States)

    Cui, Min-Hua; Cui, Dan; Gao, Lei; Cheng, Hao-Yi; Wang, Ai-Jie

    2016-10-01

    A continuous stirred tank reactor with built-in bioelectrochemical system (CSTR-BES) was developed for azo dye Alizarin Yellow R (AYR) containing wastewater treatment. The decolorization efficiency (DE) of the CSTR-BES was 97.04±0.06% for 7h with sludge concentration of 3000mg/L and initial AYR concentration of 100mg/L, which was superior to that of the sole CSTR mode (open circuit: 54.87±4.34%) and the sole BES mode (without sludge addition: 91.37±0.44%). The effects of sludge concentration and sodium acetate (NaAc) concentration on azo dye decolorization were investigated. The highest DE of CSTR-BES for 4h was 87.66±2.93% with sludge concentration of 12,000mg/L, NaAc concentration of 2000mg/L and initial AYR concentration of 100mg/L. The results in this study indicated that CSTR-BES could be a practical strategy for upgrading conventional anaerobic facilities against refractory wastewater treatment. Copyright © 2016 Elsevier Ltd. All rights reserved.

  11. A novel photoactive and three-dimensional stainless steel anode dramatically enhances the current density of bioelectrochemical systems.

    Science.gov (United States)

    Feng, Huajun; Tang, Chenyi; Wang, Qing; Liang, Yuxiang; Shen, Dongsheng; Guo, Kun; He, Qiaoqiao; Jayaprada, Thilini; Zhou, Yuyang; Chen, Ting; Ying, Xianbin; Wang, Meizhen

    2018-04-01

    This study reports a high-performance 3D stainless-steel photoanode (3D SS photoanode) for bioelectrochemical systems (BESs). The 3D SS photoanode consists of 3D carbon-coated SS felt bioactive side and a flat α-Fe 2 O 3 -coated SS plate photoactive side. Without light illumination, the electrode reached a current density of 26.2 ± 1.9 A m -2 , which was already one of the highest current densities reported thus far. Under illumination, the current density of the electrode was further increased to 46.5 ± 2.9 A m -2 . The mechanism of the photo-enhanced current production can be attributed to the reduced charge-transfer resistance between electrode surface and the biofilm with illumination. It was also found that long-term light illumination can enhance the biofilm formation on the 3D SS photoanode. These findings demonstrate that using the synergistic effect of photocatalysis and microbial electrocatalysis is an efficient way to boost the current production of the existing high-performance 3D anodes for BESs. Copyright © 2017 Elsevier Ltd. All rights reserved.

  12. In-situ growth of graphene/polyaniline for synergistic improvement of extracellular electron transfer in bioelectrochemical systems.

    Science.gov (United States)

    Sun, De-Zhen; Yu, Yang-Yang; Xie, Rong-Rong; Zhang, Chun-Lian; Yang, Yuan; Zhai, Dan-Dan; Yang, Guodong; Liu, Lei; Yong, Yang-Chun

    2017-01-15

    Graphene composite has been widely used in various bioelectrochemical systems (BES). However, it is suffered from tedious fabrication procedure and ambiguous mechanism for its effect on BES. Here, a one-step and in-situ strategy for simultaneously graphene exfoliation and aniline polymerization was developed for fabrication of graphene/PANI composite electrode (GO/PANI OS ). This GO/PANI OS outperformed graphite paper (GP), GP with PANI (GP/PANI) and GP with electrochemical exfoliated graphene (GO H2SO4 ) in Shewanella oneidensis MR-1 inoculated BES (improved the power density output, i.e., 24, 3.4 and 5.7 times of GP , GP/PANI and GO H2SO4 , respectively). Further analysis revealed a synergistic improvement on both direct and mediated extracellular electron transfer of S. oneidensis MR-1 by GO/PANI OS contributed to its performance enhancement in BES. This work not only provided a simple strategy for graphene composite fabrication, but also unveiled the underlying mechanism for its stimulation on BES, which promises new opportunity of graphene composite application in various biosystems. Copyright © 2016 Elsevier B.V. All rights reserved.

  13. Bioelectronic platforms for optimal bio-anode of bio-electrochemical systems: From nano- to macro scopes.

    Science.gov (United States)

    Kim, Bongkyu; An, Junyeong; Fapyane, Deby; Chang, In Seop

    2015-11-01

    The current trend of bio-electrochemical systems is to improve strategies related to their applicability and potential for scaling-up. To date, literature has suggested strategies, but the proposal of correlations between each research field remains insufficient. This review paper provides a correlation based on platform techniques, referred to as bio-electronics platforms (BEPs). These BEPs consist of three platforms divided by scope scale: nano-, micro-, and macro-BEPs. In the nano-BEP, several types of electron transfer mechanisms used by electrochemically active bacteria are discussed. In the micro-BEP, factors affecting the formation of conductive biofilms and transport of electrons in the conductive biofilm are investigated. In the macro-BEP, electrodes and separators in bio-anode are debated in terms of real applications, and a scale-up strategy is discussed. Overall, the challenges of each BEP are highlighted, and potential solutions are suggested. In addition, future research directions are provided and research ideas proposed to develop research interest. Copyright © 2015 Elsevier Ltd. All rights reserved.

  14. Life cycle, techno-economic and dynamic simulation assessment of bioelectrochemical systems: A case of formic acid synthesis.

    Science.gov (United States)

    Shemfe, Mobolaji; Gadkari, Siddharth; Yu, Eileen; Rasul, Shahid; Scott, Keith; Head, Ian M; Gu, Sai; Sadhukhan, Jhuma

    2018-05-01

    A novel framework, integrating dynamic simulation (DS), life cycle assessment (LCA) and techno-economic assessment (TEA) of a bioelectrochemical system (BES), has been developed to study for the first time wastewater treatment by removal of chemical oxygen demand (COD) by oxidation in anode and thereby harvesting electron and proton for carbon dioxide reduction reaction or reuse to produce products in cathode. Increases in initial COD and applied potential increase COD removal and production (in this case formic acid) rates. DS correlations are used in LCA and TEA for holistic performance analyses. The cost of production of HCOOH is €0.015-0.005 g -1 for its production rate of 0.094-0.26 kg yr -1 and a COD removal rate of 0.038-0.106 kg yr -1 . The life cycle (LC) benefits by avoiding fossil-based formic acid production (93%) and electricity for wastewater treatment (12%) outweigh LC costs of operation and assemblage of BES (-5%), giving a net 61MJkg -1 HCOOH saving. Copyright © 2018 The Authors. Published by Elsevier Ltd.. All rights reserved.

  15. Energy efficient reconcentration of diluted human urine using ion exchange membranes in bioelectrochemical systems.

    Science.gov (United States)

    Tice, Ryan C; Kim, Younggy

    2014-11-01

    Nutrients can be recovered from source separated human urine; however, nutrient reconcentration (i.e., volume reduction of collected urine) requires energy-intensive treatment processes, making it practically difficult to utilize human urine. In this study, energy-efficient nutrient reconcentration was demonstrated using ion exchange membranes (IEMs) in a microbial electrolysis cell (MEC) where substrate oxidation at the MEC anode provides energy for the separation of nutrient ions (e.g., NH4(+), HPO4(2-)). The rate of nutrient separation was magnified with increasing number of IEM pairs and electric voltage application (Eap). Ammonia and phosphate were reconcentrated from diluted human urine by a factor of up to 4.5 and 3.0, respectively (Eap = 1.2 V; 3-IEM pairs). The concentrating factor increased with increasing degrees of volume reduction, but it remained stationary when the volume ratio between the diluate (urine solution that is diluted in the IEM stack) and concentrate (urine solution that is reconcentrated) was 6 or greater. The energy requirement normalized by the mass of nutrient reconcentrated was 6.48 MJ/kg-N (1.80 kWh/kg-N) and 117.6 MJ/kg-P (32.7 kWh/kg-P). In addition to nutrient separation, the examined MEC reactor with three IEM pairs showed 54% removal of COD (chemical oxygen demand) in 47-hr batch operation. The high sulfate concentration in human urine resulted in substantial growth of both of acetate-oxidizing and H2-oxidizing sulfate reducing bacteria, greatly diminishing the energy recovery and Coulombic efficiency. However, the high microbial activity of sulfate reducing bacteria hardly affected the rate of nutrient reconcentration. With the capability to reconcentrate nutrients at a minimal energy consumption and simultaneous COD removal, the examined bioelectrochemical treatment method with an IEM application has a potential for practical nutrient recovery and sustainable treatment of source-separated human urine. Copyright © 2014

  16. Bio-electrochemical synthesis of commodity chemicals by ...

    Indian Academy of Sciences (India)

    2016-08-02

    Aug 2, 2016 ... be exploited in a bio-electrochemical system for current generation or to provide ..... fiber was desorbed directly to GC injector for 3 min. This ..... The authors are grateful to COMSATS Institute of Information. Technology ...

  17. Industrial wastewater treatment with a bioelectrochemical process: assessment of depuration efficiency and energy production.

    Science.gov (United States)

    Molognoni, Daniele; Chiarolla, Stefania; Cecconet, Daniele; Callegari, Arianna; Capodaglio, Andrea G

    2018-01-01

    Development of renewable energy sources, efficient industrial processes, energy/chemicals recovery from wastes are research issues that are quite contemporary. Bioelectrochemical processes represent an eco-innovative technology for energy and resources recovery from both domestic and industrial wastewaters. The current study was conducted to: (i) assess bioelectrochemical treatability of industrial (dairy) wastewater by microbial fuel cells (MFCs); (ii) determine the effects of the applied organic loading rate (OLR) on MFC performance; (iii) identify factors responsible for reactor energy recovery losses (i.e. overpotentials). For this purpose, an MFC was built and continuously operated for 72 days, during which the anodic chamber was fed with dairy wastewater and the cathodic chamber with an aerated mineral solution. The study demonstrated that industrial effluents from agrifood facilities can be treated by bioelectrochemical systems (BESs) with >85% (average) organic matter removal, recovering power at an observed maximum density of 27 W m -3 . Outcomes were better than in previous (shorter) analogous experiences, and demonstrate that this type of process could be successfully used for dairy wastewater with several advantages.

  18. An introduction to the life cycle assessment (LCA) of bioelectrochemical systems (BES) for sustainable energy and product generation: Relevance and key aspects

    DEFF Research Database (Denmark)

    Pant, Deepak; Singh, Anoop; Bogaert, Gilbert Van

    2011-01-01

    Bioelectrochemical systems (BESs) are devices capable of converting organic waste fraction present in wastewaters into useful energy vectors such as electricity or hydrogen. In recent years a large amount of research has been done on these unique systems in order to improve their performance both...... in terms of waste treatment as well as electric current production. Already there are plans to upscale this technology to convince the end-users of its potential. However, there are not many studies available on the life cycle of these systems with the current state of the art. In this article...... a methodology has been proposed to perform the life cycle assessment (LCA) of the BESs and some recommendations have been given which may be useful in carrying out LCA of these systems. Not only the direct benefits in terms of energy saved in aerating the wastewater treatment plants, but also the resulting...

  19. Flame-Oxidized Stainless-Steel Anode as a Probe in Bioelectrochemical System-Based Biosensors to Monitor the Biochemical Oxygen Demand of Wastewater

    Directory of Open Access Journals (Sweden)

    Qiaochu Liang

    2018-02-01

    Full Text Available Biochemical oxygen demand (BOD is a widely used index of water quality in wastewater treatment; however, conventional measurement methods are time-consuming. In this study, we analyzed a novel flame-oxidized stainless steel anode (FO-SSA for use as the probe of bioelectrochemical system (BES-based biosensors to monitor the BOD of treated swine wastewater. A thinner biofilm formed on the FO-SSA compared with that on a common carbon-cloth anode (CCA. The FO-SSA was superior to the CCA in terms of rapid sensing; the response time of the FO-SSA to obtain the value of R2 > 0.8 was 1 h, whereas the CCA required 4 h. These results indicate that the FO-SSA offers better performance than traditional CCAs in BES biosensors and can be used to improve biomonitoring of wastewater.

  20. FEDS

    DEFF Research Database (Denmark)

    Venable, John; Pries-Heje, Jan; Baskerville, Richard

    2016-01-01

    Evaluation of design artefacts and design theories is a key activity in Design Science Research (DSR), as it provides feedback for further development and (if done correctly) assures the rigour of the research. However, the extant DSR literature provides insufficient guidance on evaluation...... to enable Design Science Researchers to effectively design and incorporate evaluation activities into a DSR project that can achieve DSR goals and objectives. To address this research gap, this research paper develops, explicates, and provides evidence for the utility of a Framework for Evaluation in Design...... Science (FEDS) together with a process to guide design science researchers in developing a strategy for evaluating the artefacts they develop within a DSR project. A FEDS strategy considers why, when, how, and what to evaluate. FEDS includes a two-dimensional characterisation of DSR evaluation episodes...

  1. Novel carbon fiber cathode membrane with Fe/Mn/C/F/O elements in bio-electrochemical system (BES) to enhance wastewater treatment

    Science.gov (United States)

    Gao, Changfei; Liu, Lifen; Yang, Fenglin

    2018-03-01

    A novel conductive membrane with Fe/Mn/C/F/O elements is developed, it functions as the catalytic cathode of MFC and the antifouling filter of MBR simultaneously, in a newly designed integrated wastewater treatment system, without proton exchange membrane (PEM). The optimal conductive membrane is characterized using SEM-EDX, XRD and XPS. BET and porous structure analysis of the grounded membrane material indicate a narrow and small pore size (2-7 nm). The membrane surface is rich in Fe species (Fe - Fe2O3- Fe3O4) and manganese oxide (MnO2). Its characteristics such as excellent electro-chemical oxygen reduction reaction (ORR) activity, high clear water flux (>240 L/(m2·h)) and better antifouling filtration performance are further confirmed. The new system features bio-electrochemical system (BES) and integrates bio-filtration (trickling filter and air contact oxidation bed) and proton transfer through quartz sand chamber (QSC) which eliminates the use of expensive proton exchange membrane. The system removes chemical oxygen demand (>97.4%), ammonia nitrogen (>96.7%), total phosphorus (>98.0%) effectively, and it simultaneously generates electricity (446 mW/m3). The low cost and high performances, economic and advantageous system has good compatibility with existing wastewater treatment facilities and a wide application prospect.

  2. Facile fabrication of carbon brush with reduced graphene oxide (rGO) for decreasing resistance and accelerating pollutants removal in bio-electrochemical systems.

    Science.gov (United States)

    Cui, Dan; Yang, Li-Ming; Liu, Wen-Zong; Cui, Min-Hua; Cai, Wei-Wei; Wang, Ai-Jie

    2018-07-15

    Low electrode resistance is crucial for achieving efficient reactions in bio-electrochemical system (BES), especially considering the factors of BES scaling-up and microbial effects. Graphene has revealed a cornucopia of potential applications due to its high conductivity and extraordinary electrochemical properties. Here, significant reduction of electrode resistance and increment of electrochemical activity were achieved by fabricating the three-dimensional carbon brush using reduced graphene oxide (rGO/carbon brush) through one-step electro-deposition without any binder. The rGO/carbon brush was employed as cathode in BES equipped with bio-anode for azo compound (AO7) removal. The charge transfer resistances of cathode part and whole cell were decreased by 89% and 65%, respectively. The reactor showed quickly start-up within 48 h with peak cycle current six fold increase relative to the control. AO7 decolorization efficiency reached 91.1 ± 0.1% at 4 h and 97.6 ± 0.4% at 6 h. Effective decolorization of AO7 was at rate up to 650.7 g AO7/m 3 ·h. The results indicated that the advantages of graphene and three-dimensional carbon brush successfully improved the overall performance of BES and enhanced refractory pollutants removal when applied to specific wastewater. Copyright © 2018 Elsevier B.V. All rights reserved.

  3. A method for high throughput bioelectrochemical research based on small scale microbial electrolysis cells

    KAUST Repository

    Call, Douglas F.; Logan, Bruce E.

    2011-01-01

    There is great interest in studying exoelectrogenic microorganisms, but existing methods can require expensive electrochemical equipment and specialized reactors. We developed a simple system for conducting high throughput bioelectrochemical

  4. Performance of solar photovoltaic array fed water pumping system ...

    African Journals Online (AJOL)

    This paper discusses the design and performance analysis of a solar photovoltaic (SPV) array fed water pumping system utilizing a special class of highly rugged machine with simple drive system called switched reluctance motor (SRM) drive. The proposed method of water pumping system also provides the cost effective ...

  5. Stator insulation systems for medium voltage PWM drives fed motors

    International Nuclear Information System (INIS)

    Gao, G.; Chen, W.

    2005-01-01

    This paper presents the partial results of a research project that studied the impact of medium voltage PWM ASD (adjustable speed drives) on motor stator insulation system. The findings from this study/ investigation have aided designers to improve the robustness of the insulation system used for ASD-fed motors, based on accelerated laboratory tests. (author)

  6. Sand amendment enhances bioelectrochemical remediation of petroleum hydrocarbon contaminated soil.

    Science.gov (United States)

    Li, Xiaojing; Wang, Xin; Ren, Zhiyong Jason; Zhang, Yueyong; Li, Nan; Zhou, Qixing

    2015-12-01

    Bioelectrochemical system is an emerging technology for the remediation of soils contaminated by petroleum hydrocarbons. However, performance of such systems can be limited by the inefficient mass transport in soil. Here we report a new method of sand amendment, which significantly increases both oxygen and proton transports, resulting to increased soil porosity (from 44.5% to 51.3%), decreased Ohmic resistance (by 46%), and increased charge output (from 2.5 to 3.5Cg(-1)soil). The degradation rates of petroleum hydrocarbons increased by up to 268% in 135d. The degradation of n-alkanes and polycyclic aromatic hydrocarbons with high molecular weight was accelerated, and denaturing gradient gel electrophoresis showed that the microbial community close to the air-cathode was substantially stimulated by the induced current, especially the hydrocarbon degrading bacteria Alcanivorax. The bioelectrochemical stimulation imposed a selective pressure on the microbial community of anodes, including that far from the cathode. These results suggested that sand amendment can be an effective approach for soil conditioning that will enhances the bioelectrochemical removal of hydrocarbons in contaminated soils. Copyright © 2015 Elsevier Ltd. All rights reserved.

  7. Production performance of pigs reared in different systems and fed ...

    African Journals Online (AJOL)

    The experimental material comprised 90 growing-finishing pigs, divided into six groups of 15 animals that were diverse in terms of rearing (with or without free access to outdoor runs) and feeding systems (fed increased metabolizable energy (ME) content diets with or without green alfalfa). Different feeding regimes and ...

  8. Choice of compressed air fed system of a uranium mine

    International Nuclear Information System (INIS)

    Li Congkui; Lei Zeyong

    2006-01-01

    The selection of compressed air fed system in a uranium mine is discussed. The research indicates that the movable air compressor is better than the fixed one in energy saving, once capital cost and operational cost when it is applied in an underground uranium mine. (authors)

  9. Innovative bioelectrochemical-anaerobic-digestion integrated system for ammonia recovery and bioenergy production from ammonia-rich residues

    DEFF Research Database (Denmark)

    Zhang, Yifeng; Angelidaki, Irini

    2015-01-01

    (SMRC) and a continuous stirred tank reactor (CSTR), to prevent ammonia toxicity during anaerobic digestion by in-situ ammonia recovery and electricity production (Figure 1). In batch experiment, the ammonia concentration in the CSTR decreased from 6 to 0.7 g-N/L with an average recovery rate of 0.18 g-N/L(CSTR...... performance was enhanced. In addition, the coexistence of other cations in CSTR or cathode had no negative effect on the ammonia transportation. In continuous reactor operation, 112% extra biogas production was achieved due to ammonia recovery. High-throughput molecular sequencing analysis showed an impact...... of ammonia recovery on the microbial community composition in the integrated system. Results clearly indicate the great potential of the SMRC-CSTR-coupled system for efficient and cost-effective ammonia recovery, energy production and treatment of ammonia-rich residues....

  10. Crowbar System in Doubly Fed Induction Wind Generators

    Directory of Open Access Journals (Sweden)

    Maurício B. C. Salles

    2010-04-01

    Full Text Available In the last 15 years, the use of doubly fed induction machines in modern variable-speed wind turbines has increased rapidly. This development has been driven by the cost reduction as well as the low-loss generation of Insulated Gate Bipolar Transistors (IGBT. According to new grid code requirements, wind turbines must remain connected to the grid during grid disturbances. Moreover, they must also contribute to voltage support during and after grid faults. The crowbar system is essential to avoid the disconnection of the doubly fed induction wind generators from the network during faults. The insertion of the crowbar in the rotor circuits for a short period of time enables a more efficient terminal voltage control. As a general rule, the activation and the deactivation of the crowbar system is based only on the DC-link voltage level of the back-to-back converters. In this context, the authors discuss the critical rotor speed to analyze the instability of doubly fed induction generators during grid faults.

  11. Temperature control system for liquid-fed ceramic melters

    International Nuclear Information System (INIS)

    Westsik, J.H. Jr.

    1986-10-01

    A temperature-feedback system has been developed for controlling electrical power to liquid-fed ceramic melters (LFCM). Software, written for a microcomputer-based data acquisition and process monitoring system, compares glass temperatures with a temperature setpoint and adjusts the electrical power accordingly. Included in the control algorithm are steps to reject failed thermocouples, spatially average the glass temperatures, smooth the averaged temperatures over time using a digital filter, and detect foaming in the glass. The temperature control system has proved effective during all phases of melter operation including startup, steady operation, loss of feed, and shutdown. This system replaces current, power, and resistance feedback control systems used previously in controlling the LFCM process

  12. Bioelectrochemical conversion of CO2 to chemicals

    NARCIS (Netherlands)

    Bajracharya, Suman; Vanbroekhoven, Karolien; Buisman, Cees J.N.; Strik, David P.B.T.B.; Pant, Deepak

    2017-01-01

    The recent concept of microbial electrosynthesis (MES) has evolved as an electricity-driven production technology for chemicals from low-value carbon dioxide (CO2) using micro-organisms as biocatalysts. MES from CO2 comprises bioelectrochemical reduction of CO2 to multi-carbon organic compounds

  13. Bioelectrochemical enhancement of methane production in low temperature anaerobic digestion at 10 °C

    NARCIS (Netherlands)

    Liu, Dandan; Zhang, Lei; Chen, Si; Buisman, Cees; Heijne, ter Annemiek

    2016-01-01

    Anaerobic digestion at low temperature is an attractive technology especially in moderate climates, however, low temperature results in low microbial activity and low rates of methane formation. This study investigated if bioelectrochemical systems (BESs) can enhance methane production from

  14. Bioelectrochemical ethanol production through mediated acetate reduction by mixed cultures.

    Science.gov (United States)

    Steinbusch, Kirsten J J; Hamelers, Hubertus V M; Schaap, Joris D; Kampman, Christel; Buisman, Cees J N

    2010-01-01

    Biological acetate reduction with hydrogen is a potential method to convert wet biomass waste into ethanol. Since the ethanol concentration and reaction rates are low, this research studies the feasibility of using an electrode, in stead of hydrogen, as an electron donor for biological acetate reduction in conjunction of an electron mediator. Initially, the effect of three selected mediators on metabolic flows during acetate reduction with hydrogen was explored; subsequently, the best performing mediator was used in a bioelectrochemical system to stimulate acetate reduction at the cathode with mixed cultures at an applied cathode potential of -550 mV. In the batch test, methyl viologen (MV) was found to accelerate ethanol production 6-fold and increased ethanol concentration 2-fold to 13.5 +/- 0.7 mM compared to the control. Additionally, MV inhibited n-butyrate and methane formation, resulting in high ethanol production efficiency (74.6 +/- 6%). In the bioelectrochemical system, MV addition to an inoculated cathode led directly to ethanol production (1.82 mM). Hydrogen was coproduced at the cathode (0.0035 Nm(3) hydrogen m(-2) d(-1)), so it remained unclear whether acetate was reduced to ethanol by electrons supplied by the mediator or by hydrogen. As MV reacted irreversibly at the cathode, ethanol production stopped after 5 days.

  15. A novel bio-electrochemical system with sand/activated carbon separator, Al anode and bio-anode integrated micro-electrolysis/electro-flocculation cost effectively treated high load wastewater with energy recovery.

    Science.gov (United States)

    Gao, Changfei; Liu, Lifen; Yang, Fenglin

    2018-02-01

    A novel bio-electrochemical system (BES) was developed by integrating micro-electrolysis/electro-flocculation from attaching a sacrificing Al anode to the bio-anode, it effectively treated high load wastewater with energy recovery (maximum power density of 365.1 mW/m 3 and a maximum cell voltage of 0.97 V), and achieving high removals of COD (>99.4%), NH 4 + -N (>98.7%) and TP (>98.6%). The anode chamber contains microbes, activated carbon (AC)/graphite granules and Al anode. It was separated from the cathode chamber containing bifunctional catalytic and filtration membrane cathode (loaded with Fe/Mn/C/F/O catalyst) by a multi-medium chamber (MMC) filled with manganese sand and activated carbon granules, which replaced expensive PEM and reduced cost. An air contact oxidation bed for aeration was still adopted before liquid entering the cathode chamber. micro-electrolysis/electro-flocculation helps in achieving high removal efficiencies and contributes to membrane fouling migration. The increase of activated carbon in the separator MMC increased power generation and reduced system electric resistance. Copyright © 2017 Elsevier Ltd. All rights reserved.

  16. Bioelectrochemical probing of intracellular redox processes in living yeast cells—application of redox polymer wiring in a microfluidic environment

    DEFF Research Database (Denmark)

    Heiskanen, Arto; Coman, Vasile; Kostesha, Natalie

    2013-01-01

    utilizing a new double mediator system to map redox metabolism and screen for genetic modifications in Saccharomyces cerevisiae cells. The function of this new double mediator system based on menadione and osmium redox polymer (PVI-Os) is demonstrated. “Wiring” of S. cerevisiae cells using PVI-Os shows...... that microfluidic bioelectrochemical assays employing the menadione–PVI-Os double mediator system provides an effective means to conduct automated microbial assays. FigureMicrofluidic platform for bioelectrochemical assays using osmium redox polymer “wired” living yeast cells...

  17. Melter viewing system for liquid-fed ceramic melters

    International Nuclear Information System (INIS)

    Westsik, J.H. Jr.; Brenden, B.B.

    1988-01-01

    Melter viewing systems are an integral component of the monitoring and control systems for liquid-fed ceramic melters. The Pacific Northwest Laboratory (PNL) has designed cameras for use with glass melters at PNL, the Hanford Waste Vitrification Plant (HWVP), and West Valley Demonstration Project (WVDP). This report is a compilation of these designs. Operating experiences with one camera designed for the PNL melter are discussed. A camera has been fabricated and tested on the High-Bay Ceramic Melter (HBCM) and the Pilot-Scale Ceramic Melter (PSCM) at PNL. The camera proved to be an effective tool for monitoring the cold cap formed as the feed pool developed on the molten glass surface and for observing the physical condition of the melter. Originally, the camera was built to operate using the visible light spectrum in the melter. It was later modified to operate using the infrared (ir) spectrum. In either configuration, the picture quality decreases as the size of the cold cap increases. Large cold caps cover the molten glass, reducing the amount of visible light and reducing the plenum temperatures below 600 0 C. This temperature corresponds to the lowest level of blackbody radiation to which the video tube is sensitive. The camera has been tested in melter environments for about 1900 h. The camera has withstood mechanical shocks and vibrations. The cooling system in the camera has proved effective in maintaining the optical and electronic components within acceptable temperature ranges. 10 refs., 15 figs

  18. Classification system for rain fed wheat grain cultivars using artificial ...

    African Journals Online (AJOL)

    Artificial neural network (ANN) models have found wide applications, including ... of grains is essential for various applications as wheat grain industry and cultivation. In order to classify the rain fed wheat cultivars using artificial neural network ...

  19. Bioelectrochemical removal of carbon dioxide (CO2): an innovative method for biogas upgrading.

    Science.gov (United States)

    Xu, Heng; Wang, Kaijun; Holmes, Dawn E

    2014-12-01

    Innovative methods for biogas upgrading based on biological/in-situ concepts have started to arouse considerable interest. Bioelectrochemical removal of CO2 for biogas upgrading was proposed here and demonstrated in both batch and continuous experiments. The in-situ biogas upgrading system seemed to perform better than the ex-situ one, but CO2 content was kept below 10% in both systems. The in-situ system's performance was further enhanced under continuous operation. Hydrogenotrophic methanogenesis and alkali production with CO2 absorption could be major contributors to biogas upgrading. Molecular studies showed that all the biocathodes associated with biogas upgrading were dominated by sequences most similar to the same hydrogenotrophic methanogen species, Methanobacterium petrolearium (97-99% sequence identity). Conclusively, bioelectrochemical removal of CO2 showed great potential for biogas upgrading. Copyright © 2014 Elsevier Ltd. All rights reserved.

  20. Suitability of olive oil washing water as an electron donor in a feed batch operating bio-electrochemical system; Idoneidad del agua de lavado de aceites de oliva como donador de electrones en un sistema alimentado por lotes bioelectroquímico

    Energy Technology Data Exchange (ETDEWEB)

    Fermoso, F.G.; Fernández-Rodríguez, M.J.; Jiménez-Rodríguez, A.; Serrano, A.; Borja, R.

    2017-07-01

    Olive oil washing water derived from the two-phase manufacturing process was assessed as an electron donor in a bio-electrochemical system (BES) operating at 35 ºC. Start-up was carried out by using acetate as a substrate for the BES, reaching a potential of around +680 mV. After day 54, BES was fed with olive oil washing water. The degradation of olive oil washing water in the BES generated a maximum voltage potential of around +520 mV and a Chemical Oxygen Demand (COD) removal efficiency of 41%. However, subsequent loads produced a decrease in the COD removal, while current and power density diminished greatly. The deterioration of these parameters could be a consequence of the accumulation of recalcitrant or inhibitory compounds, such as phenols. These results demonstrated that the use of olive oil washing water as an electron donor in a BES is feasible, although it has to be further investigated in order to make it more suitable for a real application. [Spanish] El agua de lavado del aceite de oliva procedente del proceso de elaboración en dos fases fue utilizada como donador de electrones en un Sistema Bioelectroquímico (BES) operado a 35ºC. Se realizó una etapa de arranque del sistema mediante alimentación con acetato, alcanzando un potencial de referencia de +680 mV. Tras 54 días, el sistema se alimentó con agua de lavado de aceite, generando un potencial máximo de +520 mV y una eliminación de materia del 41%, en demanda química de oxígeno. Sin embargo, cargas subsecuentes conllevaron una bajada en la eliminación de materia, mientras que la densidad de corriente y de potencia disminuyeron ostensiblemente. El empeoramiento de estos parámetros puede deberse a la acumulación de compuestos recalcitrantes o inhibidores, como fenoles. Por tanto, el uso del agua de lavado de aceite de oliva en un BES es factible, aunque es necesario llevar a cabo nuevas investigaciones que hagan más atractiva su aplicación a escala real.

  1. Deposition and separation of W and Mo from aqueous solutions with simultaneous hydrogen production in stacked bioelectrochemical systems (BESs): Impact of heavy metals W(VI)/Mo(VI) molar ratio, initial pH and electrode material.

    Science.gov (United States)

    Huang, Liping; Li, Ming; Pan, Yuzhen; Quan, Xie; Yang, Jinhui; Puma, Gianluca Li

    2018-04-16

    The deposition and separation of W and Mo from aqueous solutions with simultaneous hydrogen production was investigated in stacked bioelectrochemical systems (BESs) composed of microbial electrolysis cell (1#) serially connected with parallel connected microbial fuel cell (2#). The impact of W/Mo molar ratio (in the range 0.01 mM : 1 mM and vice-versa), initial pH (1.5 to 4.0) and cathode material (stainless steel mesh (SSM), carbon rod (CR) and titanium sheet (TS)) on the BES performance was systematically investigated. The concentration of Mo(VI) was more influential than W(VI) in determining the rate of deposition of both metals and the rate of hydrogen production. Complete metal recovery was achieved at equimolar W/Mo ratio of 0.05 mM : 0.05 mM. The rates of metal deposition and hydrogen production increased at acidic pH, with the fastest rates at pH 1.5. The morphology of the metal deposits and the valence of the Mo were correlated with W/Mo ratio and pH. CR cathodes (2#) coupled with SSM cathodes (1#) achieved a significant rate of hydrogen production (0.82 ± 0.04 m 3 /m 3 /d) with W and Mo deposition (0.049 ± 0.003 mmol/L/h and 0.140 ± 0.004 mmol/L/h (1#); 0.025 ± 0.001 mmol/L/h and 0.090 ± 0.006 mmol/L/h (2#)). Copyright © 2018 Elsevier B.V. All rights reserved.

  2. Integrating sequencing batch reactor with bio-electrochemical treatment for augmenting remediation efficiency of complex petrochemical wastewater.

    Science.gov (United States)

    Yeruva, Dileep Kumar; Jukuri, Srinivas; Velvizhi, G; Naresh Kumar, A; Swamy, Y V; Venkata Mohan, S

    2015-01-01

    The present study evaluates the sequential integration of two advanced biological treatment methods viz., sequencing batch reactor (SBR) and bioelectrochemical treatment systems (BET) for the treatment of real-field petrochemical wastewater (PCW). Initially two SBR reactors were operated in aerobic (SBR(Ae)) and anoxic (SBR(Ax)) microenvironments with an organic loading rate (OLR) of 9.68 kg COD/m(3)-day. Relatively, SBR(Ax) showed higher substrate degradation (3.34 kg COD/m(3)-day) compared to SBR(Ae) (2.9 kg COD/m(3)-day). To further improve treatment efficiency, the effluents from SBR process were fed to BET reactors. BET(Ax) depicted higher SDR (1.92 kg COD/m(3)-day) with simultaneous power generation (17.12 mW/m(2)) followed by BET(Ae) (1.80 kg COD/m(3)-day; 14.25 mW/m(2)). Integrating both the processes documented significant improvement in COD removal efficiency due to the flexibility of combining multiple microenvironments sequentially. Results were supported with GC-MS and FTIR, which confirmed the increment in biodegradability of wastewater. Copyright © 2015 Elsevier Ltd. All rights reserved.

  3. Self-Driven Bioelectrochemical Mineralization of Azobenzene by Coupling Cathodic Reduction with Anodic Intermediate Oxidation

    International Nuclear Information System (INIS)

    Liu, Rong-Hua; Li, Wen-Wei; Sheng, Guo-Ping; Tong, Zhong-Hua; Lam, Michael Hon-Wah; Yu, Han-Qing

    2015-01-01

    Highlights: • Azobenzene was reduced to aniline at the cathode of an acetate-fueled MFC. • Aniline was degraded at the bioanode of a single-chamber MFC. • Cathodic reduction of azobenzene was coupled with anodic oxidation of aniline. • Self-driven, complete mineralization of azobenzene in an MFC was accomplished. - Abstract: Bioelectrochemical systems have been intensively studied as a promising technology for wastewater treatment and environment remediation. Coupling of the anodic and cathodic electrochemical reactions allows an enhanced degradation of recalcitrant organics, but external power supply is usually needed to overcome the thermodynamic barrier. In this work, we report a self-driven degradation of azobenzene in a microbial fuel cell (MFC), where the cathodic reduction of azobenzene was effectively coupled with the anodic oxidation of its reduction degradation intermediate (i.e., aniline). The anodic degradation rate of aniline, as the sole carbon source, was significantly higher than that under open-circuit conditions, suggesting a considerable bioelectrochemical oxidation of aniline. Output voltages up to 8 mV were obtained in the MFC. However, a shift of cathodic electron acceptor from oxygen to azobenzene resulted in a decreased aniline degradation rate and output voltage. The present work may provide valuable implications for development of sustainable bioelectrochemical technologies for environmental remediation

  4. Modeling of wind turbines with doubly fed generator system

    CERN Document Server

    Fortmann, Jens

    2014-01-01

    Jens Fortmann describes the deduction of models for the grid integration of variable speed wind turbines and the reactive power control design of wind plants. The modeling part is intended as background to understand the theory, capabilities and limitations of the generic doubly fed generator and full converter wind turbine models described in the IEC 61400-27-1 and as 2nd generation WECC models that are used as standard library models of wind turbines for grid simulation software. Focus of the reactive power control part is a deduction of the origin and theory behind the reactive current requ

  5. An innovative bioelectrochemical-anaerobic digestion-coupled system for in-situ ammonia recovery and biogas enhancement: process performance and microbial ecology

    DEFF Research Database (Denmark)

    Zhang, Yifeng; Angelidaki, Irini

    (SMRC) and a continuous stirred tank reactor (CSTR), to prevent ammonia toxicity during anaerobic digestion by in-situ ammonia recovery and electricity production. In batch experiment, the ammonia concentration in the CSTR decreased from 6 to 0.7 g-N/L with an average recovery rate of 0.18 g-N/L(CSTR...... performance was enhanced. In addition, the coexistence of other cations in CSTR or cathode had no negative effect on the ammonia transportation. In continuous reactor operation, 112% extra biogas production was achieved due to ammonia recovery. High-throughput molecular sequencing analysis showed an impact...... of ammonia recovery on the microbial community composition in the integrated system. Results clearly indicate the great potential of the SMRC-CSTR-coupled system for efficient and cost-effective ammonia recovery, energy production and treatment of ammonia-rich residues....

  6. Direct fed microbial supplementation repartitions host energy to the immune system.

    Science.gov (United States)

    Qiu, R; Croom, J; Ali, R A; Ballou, A L; Smith, C D; Ashwell, C M; Hassan, H M; Chiang, C-C; Koci, M D

    2012-08-01

    Direct fed microbials and probiotics are used to promote health in livestock and poultry; however, their mechanism of action is still poorly understood. We previously reported that direct fed microbial supplementation in young broilers reduced ileal respiration without changing whole-body energy expenditure. The current studies were conducted to further investigate the effects of a direct fed microbial on energy metabolism in different tissues of broilers. One hundred ninety-two 1-d-old broiler chicks (16 chicks/pen) were randomly assigned to 2 dietary groups: standard control starter diet (CSD) and CSD plus direct fed microbial (DFMD; 0.3%) with 6 pens/treatment. Body weight, feed consumption, whole-body energy expenditure, organ mass, tissue respiration rates, and peripheral blood mononuclear cell (PBMC) ATP concentrations were measured to estimate changes in energy metabolism. No differences in whole body energy expenditure or BW gain were observed; however, decreased ileal O(2) respiration (P energy consumption by PBMC corresponded with an altered immune response, broilers were immunized with sheep red blood cells (SRBC) and assayed for differences in their humoral response. The DFMD-fed broilers had a faster rate of antigen specific IgG production (P direct fed microbial used in this study resulted in energy re-partitioning to the immune system and an increase in antibody production independent of changes in whole body metabolism or growth performance.

  7. Shewanella oneidensis in a lactate-fed pure-culture and a glucose-fed co-culture with Lactococcus lactis with an electrode as electron acceptor

    Science.gov (United States)

    Bioelectrochemical systems (BESs) employing mixed microbial communities as biocatalysts are gaining importance as potential renewable energy, bioremediation, or biosensing devices. While we are beginning to understand how individual microbial species interact with an electrode as electron donor, li...

  8. Optimal design of power system stabilizer for power systems including doubly fed induction generator wind turbines

    International Nuclear Information System (INIS)

    Derafshian, Mehdi; Amjady, Nima

    2015-01-01

    This paper presents an evolutionary algorithm-based approach for optimal design of power system stabilizer (PSS) for multi-machine power systems that include doubly fed induction generator wind turbines. The proposed evolutionary algorithm is an improved particle swarm optimization named chaotic particle swarm optimization with passive congregation (CPSO-PC) applied for finding the optimal settings of PSS parameters. Two different eigenvalue-based objectives are combined as the objective function for the optimization problem of tuning PSS parameters. The first objective function comprises the damping factor of lightly damped electro-mechanical modes and the second one includes the damping ratio of these modes. The effectiveness of the proposed method to design PSS for the power systems including DFIG (Doubly Fed Induction Generator) is extensively demonstrated through eigenvalue analysis and time-domain simulations and also by comparing its simulation results with the results of other heuristic optimization approaches. - Highlights: • A new optimization model for design of PSS in power systems including DFIG is proposed. • A detailed and realistic modeling of DFIG is presented. • A new evolutionary algorithm is suggested for solving the optimization problem of designing PSS

  9. Performance of solar photovoltaic array fed water pumping system ...

    African Journals Online (AJOL)

    DR OKE

    proposed method of water pumping system also provides the cost effective and highly ... in the proposed system because of its similar operational characteristics compared to SPV generator. .... (CCM) regardless of the atmospheric conditions.

  10. Design of double-fed control system for J-TEXT 100 MVA pulse generator unit

    International Nuclear Information System (INIS)

    Fang, Jianming; Yu, Kexun; Zhang, Ming; Zhuang, Ge; Xiao, Zhiguo; Jiang, Guozhong; Yang, Cheng; Xu, Jiayu

    2013-01-01

    Highlights: ► A double-fed control system is designed for J-TEXT 100 MVA pulse generator unit. ► The double-fed system can control the motor speed and reactive power individually. ► Experiment on a prototype motor shows a good control result. -- Abstract: The 100 MVA pulse generator unit is the main power supply of J-TEXT. This unit supplies energy for the toroidal coil, the ohmic heat coil and the divertor coil, with the maximum stored energy 185 MJ. For the difference of grid frequency between China and USA, the rotational speed and stored energy of this unit are less than the designed value. A double-fed control system for the unit is designed to raise them. This double-fed system has applied a control method using a rotational reference frame oriented by stator flux. With this control system, the speed and reactive power of motor could be controlled individually. Experiments on a prototype motor show a good control result

  11. Solar pv fed stand-alone excitation system of a synchronous machine for reactive power generation

    Science.gov (United States)

    Sudhakar, N.; Jain, Siddhartha; Jyotheeswara Reddy, K.

    2017-11-01

    This paper presents a model of a stand-alone solar energy conversion system based on synchronous machine working as a synchronous condenser in overexcited state. The proposed model consists of a Synchronous Condenser, a DC/DC boost converter whose output is fed to the field of the SC. The boost converter is supplied by the modelled solar panel and a day time variable irradiance is fed to the panel during the simulation time. The model also has one alternate source of rechargeable batteries for the time when irradiance falls below a threshold value. Also the excess power produced when there is ample irradiance is divided in two parts and one is fed to the boost converter while other is utilized to recharge the batteries. A simulation is done in MATLAB-SIMULINK and the obtained results show the utility of such modelling for supplying reactive power is feasible.

  12. Loss Minimizing Operation of Doubly Fed Induction Generator Based Wind Generation Systems Considering Reactive Power Provision

    DEFF Research Database (Denmark)

    Baohua, Zhang; Hu, Weihao; Chen, Zhe

    2014-01-01

    The paper deals with control techniques for minimizing the operating loss of doubly fed induction generator based wind generation systems when providing reactive power. The proposed method achieves its goal through controlling the rotor side q-axis current in the synchronous reference frame...

  13. Hopf bifurcation and eigenvalue sensitivity analysis of doubly fed induction generator wind turbine system

    DEFF Research Database (Denmark)

    Yang, Li Hui; Xu, Zhao; Østergaard, Jacob

    2010-01-01

    This paper first presents the Hopf bifurcation analysis for a vector-controlled doubly fed induction generator (DFIG) which is widely used in wind power conversion systems. Using three-phase back-to-back pulse-width-modulated (PWM) converters, DFIG can keep stator frequency constant under variabl...

  14. Analysis of a bio-electrochemical reactor containing carbon fiber textiles for the anaerobic digestion of tomato plant residues.

    Science.gov (United States)

    Hirano, Shin-Ichi; Matsumoto, Norio

    2018-02-01

    A bio-electrochemical system packed with supporting material can promote anaerobic digestion for several types of organic waste. To expand the target organic matters of a BES, tomato plant residues (TPRs), generated year-round as agricultural and cellulosic waste, were treated using three methanogenic reactors: a continuous stirred tank reactor (CSTR), a carbon fiber textile (CFT) reactor, and a bio-electrochemical reactor (BER) including CFT with electrochemical regulation (BER + CFT). CFT had positive effects on methane fermentation and methanogen abundance. The microbial population stimulated by electrochemical regulation, including hydrogenotrophic methanogens, cellulose-degrading bacteria, and acetate-degrading bacteria, suppressed acetate accumulation, as evidenced by the low acetate concentration in the suspended fraction in the BER + CFT. These results indicated that the microbial community in the BER + CFT facilitated the efficient decomposition of TPR and its intermediates such as acetate to methane. Copyright © 2017 Elsevier Ltd. All rights reserved.

  15. Modelling and properties of a nonlinear autonomous switching system in fed-batch culture of glycerol

    Science.gov (United States)

    Wang, Juan; Sun, Qingying; Feng, Enmin

    2012-11-01

    A nonlinear autonomous switching system is proposed to describe the coupled fed-batch fermentation with the pH as the feedback parameter. We prove the non-Zeno behaviors of the switching system and some basic properties of its solution, including the existence, uniqueness, boundedness and regularity. Numerical simulation is also carried out, which reveals that the proposed system can describe the factual fermentation process properly.

  16. Performance of integrated bioelectrochemical membrane reactor: Energy recovery, pollutant removal and membrane fouling alleviation

    Science.gov (United States)

    Dong, Yue; He, Weihua; Li, Chao; Liang, Dandan; Qu, Youpeng; Han, Xiaoyu; Feng, Yujie

    2018-04-01

    A novel hybrid bioelectrochemical membrane reactor with integrated microfiltration membrane as the separator between electrodes is developed for domestic wastewater treatment. After accumulation of biofilm, the organic pollutants are mainly degraded in anodic compartment, and microfiltration membrane blocks the adverse leakage of dissolved oxygen from aerated cathodic compartment. The maximum system power output is restricted by gas-water ratio following a Monod-like relationship. Within the tested gas-water ratios ranging from 0.6 to 42.9, the half-saturation constant (KQ) is 5.9 ± 0.9 with a theoretic maximum power density of 20.4 ± 1.0 W m-3. Energy balance analysis indicates an appropriate gas-water ratio regulation (from 2.3 to 28.6) for cathodic compartment is necessary to obtain positive energy output for the system. A maximum net electricity output is 9.09 × 10-3 kWh m-3 with gas-water ratio of 17.1. Notably, the system achieves the chemical oxygen demand removal of 98.3 ± 0.3%, ammonia nitrogen removal of 99.6 ± 0.1%, and total nitrogen removal of 80.0 ± 0.9%. This work verifies an effective integration of microfiltration membrane into bioelectrochemical system as separator for high-quality effluent and provides an insight into the operation and regulation of biocathode system for effective electrical energy output.

  17. Nonlinear impulsive system of fed-batch culture in fermentative production and its properties

    International Nuclear Information System (INIS)

    Gao Caixia; Li Kezan; Feng Enmin; Xiu Zhilong

    2006-01-01

    In this study, the nonlinear dynamical system of fed-batch fermentation is investigated in the process of bio-dissimilation of glycerol to 1,3-propanediol by Klebsiella pneumoniae. Considering the abrupt increase of glycerol in fed-batch culture, this paper proposes a nonlinear impulsive system of the culture process, which is fit for formulating the factual fermentation better than the continuous models in being. We study the questions of existence and properties of mild solutions for the system and the continuous dependence of solutions on initial values and the controllable variable. Finally, the numerical simulations show that the errors between experimental and computational values using the impulsive system are less than those using the previous continuous system

  18. Systemic distribution and speciation of diphenylarsinic acid fed to rats

    International Nuclear Information System (INIS)

    Naranmandura, Hua; Suzuki, Noriyuki; Takano, Juniti; McKnight-Whitford, Tony; Ogra, Yasumitsu; Suzuki, Kazuo T.; Le, X. Chris

    2009-01-01

    Diphenylarsinic acid (DPAA) is an environmental degradation product of diphenylarsine chloride or diphenylarsine cyanide, which were chemical warfare agents produced by Japan during the World War II. DPAA is now considered a dangerous environmental pollutant in Kamisu, Japan, where it is suspected of inducing health effects that include articulation disorders (cerebellar ataxia of the extremities and trunk), involuntary movements (myoclonus and tremor), and sleep disorders. In order to elucidate the toxic mechanism of DPAA, we focused on the distribution and metabolism of DPAA in rats. Systemic distribution of DPAA was determined by administering DPAA orally to rats at a single dose of 5.0 mg As/kg body weight, followed by speciation analysis of selected organs and body fluids. Most of the total arsenic burden was recovered in the urine (23% of the dose) and feces (27%), with the distribution in most other organs/tissues being less than 1%. However, compared with the typical distribution of inorganic dietary arsenic, DPAA administration resulted in elevated levels in the brain, testes and pancreas. In contrast to urine, in which DPAA was found mostly in its unmodified form, the tissues and organs contained arsenic that was mostly bound to non-soluble and soluble high molecular weight proteins. These bound arsenic species could be converted back to DPAA after oxidation with H 2 O 2 , suggesting that the DPAA bound to proteins had been reduced within the body and was in a trivalent oxidation state. Furthermore, we also detected two unknown arsenic metabolites in rat urine, which were assumed to be hydroxylated arsenic metabolites.

  19. Prospects for Improving Gravity-Fed Surface Irrigation Systems in Mediterranean European Contexts

    Directory of Open Access Journals (Sweden)

    Daniele Masseroni

    2017-01-01

    Full Text Available Traditionally, most irrigation practices in Southern Europe have been based on gravity-fed surface irrigation systems. Currently, these systems remain a relevant typology in the European Union (EU member states of the Mediterranean areas, where it is often the only sustainable method for farmers due to the small size of agricultural holdings, their reduced capacity and readiness to invest and the low ratio between yield profits and irrigation costs. In the last several years, in response to European and national directives, surface irrigation has garnered increasing attention at the political and bureaucratic levels due to frequent criticisms of its postulated low efficiency and high water wastage. However, these systems commonly provide a number of ecosystem services and nature-based solutions that increase the positive externalities in different rural socio-ecological contexts and often have the potential to extend these services and provide solutions that are compatible with economical sustainability. This study aims to discuss the prospects for new practices and for the rehabilitation and modernization of the gravity-fed surface irrigation systems in EU Mediterranean areas to enhance water efficiency, thus gaining both economic advantages and environmental benefits. The difficulties, stimuli for improvements and peculiarities of the irrigation water management of four rural environments located in Italy, Spain and Portugal were analyzed and compared to the current state of the gravity-fed surface irrigation systems with hypothetical future improvements achievable by innovative technologies and practices. In these different case studies, the current gravity-fed surface irrigation systems have an obsolete regulatory structure; water-use efficiency is not a driving criterion for the management of the conveyance and distribution canal network, and farmers are not yet adequately encouraged to adopt more efficient gravity-fed irrigation practices

  20. Thermal hydraulics of the impurity control system for FED/INTOR

    International Nuclear Information System (INIS)

    Cha, Y.S.; Mattas, R.F.; Abdou, M.A.; Haines, J.R.

    1983-01-01

    This paper addresses two important aspects of thermal hydraulics related to the design of the impurity control system (limiter and divertor) of the Fusion Engineering Device (FED) and the International Tokamak Reactor (INTOR). The first part of the paper is devoted to the determination of temperature distributions in various combinations of the coating/structural materials proposed for the limiter/divertor of FED and INTOR. The second part of the paper describes the analysis of the tangential motion of the melt layer under the influence of magnetic force during plasma disruption. The results of both analysis provide inputs to the determination of the life time of the limiter (or divertor) which is the most critical problem for the impurity control system as far as engineering and materials consideration is concerned

  1. Bio-electrochemical synthesis of commodity chemicals by autotrophic acetogens utilizing CO2 for environmental remediation.

    Science.gov (United States)

    Jabeen, Gugan; Farooq, Robina

    2016-09-01

    Bio-electrochemical synthesis (BES) is a technique in which electro-autotrophic bacteria such as Clostridium ljungdahlii utilize electric currents as an electron source from the cathode to reduce CO2 to extracellular, multicarbon, exquisite products through autotrophic conversion. The BES of volatile fatty acids and alcohols directly from CO2 is a sustainable alternative for non-renewable, petroleum-based polymer production. This conversion of CO2 implies reduction of greenhouse gas emissions. The synthesis of heptanoic acid, heptanol, hexanoic acid and hexanol, for the first time, by Clostridium ljungdahlii was a remarkable achievement of BES. In our study, these microorganisms were cultivated on the cathode of a bio-electrochemical cell at -400 mV by a DC power supply at 37 degree Centrigrade, pH 6.8, and was studied for both batch and continuous systems. Pre-enrichment of bio-cathode enhanced the electroactivity of cells and resulted in maximizing extracellular products in less time. The main aim of the research was to investigate the impact of low-cost substrate CO2, and the longer cathode recovery range was due to bacterial reduction of CO2 to multicarbon chemical commodities with electrons driven from the cathode. Reactor design was simplified for cost-effectiveness and to enhance energy efficiencies. The Columbic recovery of ethanoic acid, ethanol, ethyl butyrate, hexanoic acid, heptanoic acid and hexanol being in excess of 80 percent proved that BES was a remarkable technology.

  2. Continuous fed-batch vacuum fermentation system for glycerol from molasses by the sulfite process

    Energy Technology Data Exchange (ETDEWEB)

    Kalle, G.P.; Naik, S.C.

    1985-01-01

    A continuous fed-batch vacuum fermentation system has been described for the production of glycerol from cane molasses (and juice) by a conventional sulfite process. A glycerol concentration of 80 g/l was achieved with a productivity of 30 g/l/day at a dilution rate of 0.4/day which is twice that from a vacuum batch process (15 g/l/day) or four times that obtained without vacuum (8 g/l/day). 8 references.

  3. Thermoelectric characterization of an intermediate temperature solid oxide fuel cell system directly fed by dry biogas

    International Nuclear Information System (INIS)

    De Lorenzo, G.; Corigliano, O.; Lo Faro, M.; Frontera, P.; Antonucci, P.; Zignani, S.C.; Trocino, S.; Mirandola, F.A.; Aricò, A.S.; Fragiacomo, P.

    2016-01-01

    Highlights: • Numerical Model (NM) of SOFC Cogenerative System (SCS) fed by dry biogas is set up. • NM simulates new Ni-Fe/CGO protective layer for direct CH_4 consumption at the anode. • NM simulates the anode carbonation phenomenon and is experimentally validated. • The performance parameters trends of SCS fed by three types of dry biogas are shown. • SEM images after 40 h of operation show that there is no anode carbon deposition. - Abstract: A properly manufactured intermediate temperature Solid Oxide Fuel Cell (SOFC) can be directly fed by dry biogas, considering also the electrochemical partial and total oxidation reactions of methane in the biogas at the anode. In this way the methane in the biogas is electrochemically consumed directly at the fuel cell without the need to mix the biogas with any reforming gas (steam, oxygen or carbon dioxide). In this article, a numerical model of an SOFC system with Ni-Fe/CGO electrocatalyst anode protective layer directly fed by dry biogas, in cogenerative arrangement and with anode exhaust gas recirculation is formulated. The influences of biogas composition, of fuel cell operating current density and of percentage of recirculated anode exhaust gas on the SOFC system performances were evaluated by calculation code. An SOFC test bench was set up to validate the calculation code results experimentally. Furthermore, the numerical model also considers the anode carbonation and evaluates the amount of carbon that can be formed in the anode at chemical equilibrium and quasi-equilibrium conditions associated with the specific anode protective layer used.

  4. A new nordic structure evaluation system for diets fed to dairy cows

    DEFF Research Database (Denmark)

    Nørgaard, Peder; Nadeau, E.; Volden, H.

    2008-01-01

    on eating, ruminating and total chewing time by cattle fed mainly high forage diets. The EI is proportional with the neutral detergent fibre (NDF) content and a particle size factor (Size_E) of the feed. The RI is proportional with the NDF content, a particle size factor (Size_R) and a hardness factor...... per kg of total DMI is considered to ensure a sufficient intake of physically effective fibre in order to ensure good ruminal fibre digestion and to prevent a low rumen pH, digestive disorders and a low milk fat content in high-yielding dairy cows.......The objective of the Norfor structure system was to establish a model for prediction of eating- (EI), ruminating- (RI) and total chewing index (CI) for feeds and total rations fed to dairy cows. The model was predicted from a Meta analysis of more than 100 published experiments including results...

  5. Optimization of high solids fed-batch saccharification of sugarcane bagasse based on system viscosity changes.

    Science.gov (United States)

    Liu, Yunyun; Xu, Jingliang; Zhang, Yu; Yuan, Zhenhong; Xie, Jun

    2015-10-10

    Viscosity trends in alkali-pretreated sugarcane bagasse (SCB) slurries undergoing high solids fed-batch enzymatic hydrolysis were measured for a range of solids loading from 15% to 36%. Solids liquefaction times were related to system viscosity changes. The viscosity decreased quickly for low solids loading, and increased with increasing solids content. Fed-batch hydrolysis was initiated with 15% solids loading, and an additional 8%, 7% and 6% were successively added after the system viscosity decreased to stable values to achieve a final solids content of 36%. Two enzyme-adding modes with 8.5FPU/g solid were investigated. The batch mode with all enzyme being added at the beginning of the reaction produced the highest yields, with approximately 231.7g/L total sugars and 134.9g/L glucose being obtained after 96h with nearly 60% of the final glucan conversion rate. This finding indicates that under the right conditions, the fed-batch strategy might be a plausible way to produce high sugars under high solids. Copyright © 2015 Elsevier B.V. All rights reserved.

  6. Doubly fed induction generator based wind turbine systems subject to recurring grid faults

    DEFF Research Database (Denmark)

    Chen, Wenjie; Blaabjerg, Frede; Zhu, Nan

    2014-01-01

    New grid codes demand the wind turbine systems to ride through recurring grid faults. In this paper, the performance of the Doubly Fed Induction Generator wind turbine system under recurring grid faults is analyzed. The stator natural flux produced by the voltage recovery after the first grid fault...... may be superposed on the stator natural flux produced by the second grid fault, and it may result in large current and voltage transient. The damping of the stator natural flux can be accelerated with a rotor natural current in its opposite direction after voltage recovery, but larger torque....... The performance of DFIG under recurring grid faults is verified by the simulation and experiments....

  7. Maximum Wind Power Tracking of Doubly Fed Wind Turbine System Based on Adaptive Gain Second-Order Sliding Mode

    Directory of Open Access Journals (Sweden)

    Hongchang Sun

    2018-01-01

    Full Text Available This paper proposes an adaptive gain second-order sliding mode control strategy to track optimal electromagnetic torque and regulate reactive power of doubly fed wind turbine system. Firstly, wind turbine aerodynamic characteristics and doubly fed induction generator (DFIG modeling are presented. Then, electromagnetic torque error and reactive power error are chosen as sliding variables, and fixed gain super-twisting sliding mode control scheme is designed. Considering that uncertainty upper bound is unknown and is hard to be estimated in actual doubly fed wind turbine system, a gain scheduled law is proposed to compel control parameters variation according to uncertainty upper bound real-time. Adaptive gain second-order sliding mode rotor voltage control method is constructed in detail and finite time stability of doubly fed wind turbine control system is strictly proved. The superiority and robustness of the proposed control scheme are finally evaluated on a 1.5 MW DFIG wind turbine system.

  8. A fluidized bed membrane bioelectrochemical reactor for energy-efficient wastewater treatment.

    Science.gov (United States)

    Li, Jian; Ge, Zheng; He, Zhen

    2014-09-01

    A fluidized bed membrane bioelectrochemical reactor (MBER) was investigated using fluidized granular activated carbon (GAC) as a mean of membrane fouling control. During the 150-day operation, the MBER generated electricity with contaminant removal from either synthetic solution or actual wastewater, as a standalone or a coupled system. It was found that fluidized GAC could significantly reduce transmembrane pressure (TMP), although its function as a part of the anode electrode was minor. When the MBER was linked to a regular microbial fuel cell (MFC) for treating a wastewater from a cheese factory, the MFC acted as a major process for energy recovery and contaminant removal, and the coupled system removed more than 90% of chemical oxygen demand and >80% of suspended solids. The analysis showed that the ratio of energy recovery and consumption was slightly larger than one, indicating that the coupled system could be theoretically energy neutral. Copyright © 2014 Elsevier Ltd. All rights reserved.

  9. Model for Investigation of Operational Wind Power Plant Regimes with Doubly–Fed Asynchronous Machine in Power System

    Directory of Open Access Journals (Sweden)

    R. I. Mustafayev

    2012-01-01

    Full Text Available The paper presents methodology for mathematical modeling of power system (its part when jointly operated with wind power plants (stations that contain asynchronous doubly-fed machines used as generators. The essence and advantage of the methodology is that it allows efficiently to mate equations of doubly-fed asynchronous machines, written in the axes that rotate with the machine rotor speed with the equations of external electric power system, written in synchronously rotating axes.

  10. Power system stabilization by SMES using current-fed pwm power conditioner

    International Nuclear Information System (INIS)

    Ishikawa, T.; Akita, S.; Taniguchi, H.; Kosho, S.; Tanaka, T.

    1988-01-01

    A superconducting magnetic energy storage (SMES) unit, consisted of superconducting coil and AC/DC power conditioner, can be used to suppress various kinds of instability that may cause service interruption in electric power system as it has high controllability of input/output electric power. Power system stabilizing ability of SMES has been examined experimentally by using model power system and small SMES unit. Current-fed PWM power conditioner was used to obtain maximum stabilizing effect by controlling active and reactive power simultaneously and independently. Power conditioner configuration, operating characteristics and control scheme for power system stabilization are also described. Results from experiments show the effectiveness of SMES on power system stabilization

  11. Modern control strategies of doubly-fed induction generator based wind turbine system

    DEFF Research Database (Denmark)

    Zhou, Dao; Song, Yipeng; Blaabjerg, Frede

    2016-01-01

    A doubly-fed induction generator (DFIG) based configuration is still preferred by wind turbine manufactures due to the cost-effective power converter and independent control of the active power and reactive power. To cope with stricter grid codes (e.g. reactive power compensation, low voltage ride......, with the control targets of the smooth active and reactive power or the balances and sinusoidal current of the rotor-side converter and the grid-side converter. Finally, a bandwidth based repetitive controller is evaluated to improve the DFIG system's robustness against grid frequency deviation....

  12. Addressing fuel recycling in solid oxide fuel cell systems fed by alternative fuels

    DEFF Research Database (Denmark)

    Rokni, Masoud

    2017-01-01

    An innovative study on anode recirculation in solid oxide fuel cell systems with alternative fuels is carried out and investigated. Alternative fuels under study are ammonia, pure hydrogen, methanol, ethanol, DME and biogas from biomass gasification. It is shown that the amount of anode off......%. Furthermore, it is founded that for the case with methanol, ethanol and DME then at high utilization factors, low anode recirculation is recommended while at low utilization factors, high anode recirculation is recommended. If the plant is fed by biogas from biomass gasification then for each utilization...

  13. Bioelectrochemical treatment of acid mine drainage dominated with iron

    International Nuclear Information System (INIS)

    Lefebvre, Olivier; Neculita, Carmen M.; Yue, Xiaodi; Ng, How Yong

    2012-01-01

    Highlights: ► Treatment of AMD dominated with Fe is problematic due to its low pH. ► The goal of AMD treatment is pH increasing and Fe controlled removal. ► An MFC could fulfill both these requirements by treating AMD at the aerated cathode. ► The performance was proportional to the charge transfer up to 880 C. ► The treated AMD met the discharge limits both for Fe (>99% recovery) and pH (7.9). - Abstract: Treatment of acid mine drainage (AMD) dominated with iron (Fe), the most common metal, is a long-term expensive commitment, the goal of which is to increase the pH and remove Fe. In the present study, a proton exchange membrane microbial fuel cell (MFC) showed promise for the efficient treatment of an AMD dominated with ferric iron (pH 2.4 ± 0.1; 500 mg L −1 Fe 3+ ). Briefly, Fe 3+ was reduced to Fe 2+ at the cathode of the MFC, followed by Fe 2+ re-oxidation and precipitation as oxy(hydroxi)des. Oxygen reduction and cation transfer to the cathode of the MFC further caused a rise in pH. A linear relationship was observed between the charge transferred in the MFC and the performance of the system up to 880 C. Optimal conditions were found at a charge of 662 C, achieved within 7 d at an acetate concentration of 1.6 g L −1 in a membrane MFC. This caused the pH to rise to 7.9 and resulted in a Fe removal of 99%. Treated effluent met the pH discharge limits of 6.5–9. The maximum power generation achieved under these conditions averaged 8.6 ± 2.3 W m −3 , which could help reduce the costs of full-scale bioelectrochemical treatment of AMD dominated with Fe.

  14. Increased methylglyoxal formation with upregulation of renin angiotensin system in fructose fed Sprague Dawley rats.

    Directory of Open Access Journals (Sweden)

    Indu Dhar

    Full Text Available The current epidemic of obesity and type 2 diabetes is attributed to a high carbohydrate diet, containing mainly high fructose corn syrup and sucrose. More than two thirds of diabetic patients have hypertension. Methylglyoxal is a highly reactive dicarbonyl generated during glucose and fructose metabolism, and a major precursor of advanced glycation end products (AGEs. Plasma methylglyoxal levels are increased in hypertensive rats and diabetic patients. Our aim was to examine the levels of methylglyoxal, mediators of the renin angiotensin system and blood pressure in male Sprague-Dawley rats treated with a high fructose diet (60% of total calories for 4 months. The thoracic aorta and kidney were used for molecular studies, along with cultured vascular smooth muscle cells (VSMCs. HPLC, Western blotting and Q-PCR were used to measure methylglyoxal and reduced glutathione (GSH, proteins and mRNA, respectively. Fructose treated rats developed a significant increase in blood pressure. Methylglyoxal level and protein and mRNA for angiotensin II, AT1 receptor, adrenergic α1D receptor and renin were significantly increased, whereas GSH levels were decreased, in the aorta and/or kidney of fructose fed rats. The protein expression of the receptor for AGEs (RAGE and NF-κB were also significantly increased in the aorta of fructose fed rats. MG treated VSMCs showed increased protein for angiotensin II, AT1 receptor, and α1D receptor. The effects of methylglyoxal were attenuated by metformin, a methylglyoxal scavenger and AGEs inhibitor. In conclusion, we report a strong association between elevated levels of methylglyoxal, RAGE, NF-κB, mediators of the renin angiotensin system and blood pressure in high fructose diet fed rats.

  15. Increased methylglyoxal formation with upregulation of renin angiotensin system in fructose fed Sprague Dawley rats.

    Science.gov (United States)

    Dhar, Indu; Dhar, Arti; Wu, Lingyun; Desai, Kaushik M

    2013-01-01

    The current epidemic of obesity and type 2 diabetes is attributed to a high carbohydrate diet, containing mainly high fructose corn syrup and sucrose. More than two thirds of diabetic patients have hypertension. Methylglyoxal is a highly reactive dicarbonyl generated during glucose and fructose metabolism, and a major precursor of advanced glycation end products (AGEs). Plasma methylglyoxal levels are increased in hypertensive rats and diabetic patients. Our aim was to examine the levels of methylglyoxal, mediators of the renin angiotensin system and blood pressure in male Sprague-Dawley rats treated with a high fructose diet (60% of total calories) for 4 months. The thoracic aorta and kidney were used for molecular studies, along with cultured vascular smooth muscle cells (VSMCs). HPLC, Western blotting and Q-PCR were used to measure methylglyoxal and reduced glutathione (GSH), proteins and mRNA, respectively. Fructose treated rats developed a significant increase in blood pressure. Methylglyoxal level and protein and mRNA for angiotensin II, AT1 receptor, adrenergic α1D receptor and renin were significantly increased, whereas GSH levels were decreased, in the aorta and/or kidney of fructose fed rats. The protein expression of the receptor for AGEs (RAGE) and NF-κB were also significantly increased in the aorta of fructose fed rats. MG treated VSMCs showed increased protein for angiotensin II, AT1 receptor, and α1D receptor. The effects of methylglyoxal were attenuated by metformin, a methylglyoxal scavenger and AGEs inhibitor. In conclusion, we report a strong association between elevated levels of methylglyoxal, RAGE, NF-κB, mediators of the renin angiotensin system and blood pressure in high fructose diet fed rats.

  16. Equivalent model of a dually-fed machine for electric drive control systems

    Science.gov (United States)

    Ostrovlyanchik, I. Yu; Popolzin, I. Yu

    2018-05-01

    The article shows that the mathematical model of a dually-fed machine is complicated because of the presence of a controlled voltage source in the rotor circuit. As a method of obtaining a mathematical model, the method of a generalized two-phase electric machine is applied and a rotating orthogonal coordinate system is chosen that is associated with the representing vector of a stator current. In the chosen coordinate system in the operator form the differential equations of electric equilibrium for the windings of the generalized machine (the Kirchhoff equation) are written together with the expression for the moment, which determines the electromechanical energy transformation in the machine. Equations are transformed so that they connect the currents of the windings, that determine the moment of the machine, and the voltages on these windings. The structural diagram of the machine is assigned to the written equations. Based on the written equations and accepted assumptions, expressions were obtained for the balancing the EMF of windings, and on the basis of these expressions an equivalent mathematical model of a dually-fed machine is proposed, convenient for use in electric drive control systems.

  17. Endocrine disruptive estrogens role in electron transfer: bio-electrochemical remediation with microbial mediated electrogenesis.

    Science.gov (United States)

    Kumar, A Kiran; Reddy, M Venkateswar; Chandrasekhar, K; Srikanth, S; Mohan, S Venkata

    2012-01-01

    Bioremediation of selected endocrine disrupting compounds (EDCs)/estrogens viz. estriol (E3) and ethynylestradiol (EE2) was evaluated in bio-electrochemical treatment (BET) system with simultaneous power generation. Estrogens supplementation along with wastewater documented enhanced electrogenic activity indicating their function in electron transfer between biocatalyst and anode as electron shuttler. EE2 addition showed more positive impact on the electrogenic activity compared to E3 supplementation. Higher estrogen concentration showed inhibitory effect on the BET performance. Poising potential during start up phase showed a marginal influence on the power output. The electrons generated during substrate degradation might have been utilized for the EDCs break down. Fuel cell behavior and anodic oxidation potential supported the observed electrogenic activity with the function of estrogens removal. Voltammetric profiles, dehydrogenase and phosphatase enzyme activities were also found to be in agreement with the power generation, electron discharge and estrogens removal. Copyright © 2011 Elsevier Ltd. All rights reserved.

  18. Dynamic Average-Value Modeling of Doubly-Fed Induction Generator Wind Energy Conversion Systems

    Science.gov (United States)

    Shahab, Azin

    In a Doubly-fed Induction Generator (DFIG) wind energy conversion system, the rotor of a wound rotor induction generator is connected to the grid via a partial scale ac/ac power electronic converter which controls the rotor frequency and speed. In this research, detailed models of the DFIG wind energy conversion system with Sinusoidal Pulse-Width Modulation (SPWM) scheme and Optimal Pulse-Width Modulation (OPWM) scheme for the power electronic converter are developed in detail in PSCAD/EMTDC. As the computer simulation using the detailed models tends to be computationally extensive, time consuming and even sometimes not practical in terms of speed, two modified approaches (switching-function modeling and average-value modeling) are proposed to reduce the simulation execution time. The results demonstrate that the two proposed approaches reduce the simulation execution time while the simulation results remain close to those obtained using the detailed model simulation.

  19. A Short-Current Control Method for Constant Frequency Current-Fed Wireless Power Transfer Systems

    Directory of Open Access Journals (Sweden)

    Yanling Li

    2017-04-01

    Full Text Available Frequency drift is a serious problem in Current-Fed Wireless Power Transfer (WPT systems. When the operating frequency is drifting from the inherent Zero Voltage Switching (ZVS frequency of resonant network, large short currents will appear and damage the switches. In this paper, an inductance-dampening method is proposed to inhibit short currents and achieve constant-frequency operation. By adding a small auxiliary series inductance in the primary resonant network, short currents are greatly attenuated to a safe level. The operation principle and steady-state analysis of the system are provided. An overlapping time self-regulating circuit is designed to guarantee ZVS running. The range of auxiliary inductances is discussed and its critical value is calculated exactly. The design methodology is described and a design example is presented. Finally, a prototype is built and the experimental results verify the proposed method.

  20. Dynamic response characteristics analysis of the doubly-fed wind power system under grid voltage drop

    Science.gov (United States)

    Chen, Y.; Wang, J.; Wang, H. H.; Yang, L.; Chen, W.; Xu, Y. T.

    2016-08-01

    Double-fed induction generator (DFIG) is sensitive to the disturbances of grid, so the security and stability of the grid and the DFIG itself are under threat with the rapid increase of DFIG. Therefore, it is important to study dynamic response of the DFIG when voltage drop failure is happened in power system. In this paper, firstly, mathematical models and the control strategy about mechanical and electrical response processes is respectively introduced. Then through the analysis of response process, it is concluded that the dynamic response characteristics are related to voltage drop level, operating status of DFIG and control strategy adapted to rotor side. Last, the correctness of conclusion is validated by the simulation about mechanical and electrical response processes in different voltage levels drop and different DFIG output levels under DIgSILENT/PowerFactory software platform.

  1. A joint FED watermarking system using spatial fusion for verifying the security issues of teleradiology.

    Science.gov (United States)

    Viswanathan, P; Krishna, P Venkata

    2014-05-01

    Teleradiology allows transmission of medical images for clinical data interpretation to provide improved e-health care access, delivery, and standards. The remote transmission raises various ethical and legal issues like image retention, fraud, privacy, malpractice liability, etc. A joint FED watermarking system means a joint fingerprint/encryption/dual watermarking system is proposed for addressing these issues. The system combines a region based substitution dual watermarking algorithm using spatial fusion, stream cipher algorithm using symmetric key, and fingerprint verification algorithm using invariants. This paper aims to give access to the outcomes of medical images with confidentiality, availability, integrity, and its origin. The watermarking, encryption, and fingerprint enrollment are conducted jointly in protection stage such that the extraction, decryption, and verification can be applied independently. The dual watermarking system, introducing two different embedding schemes, one used for patient data and other for fingerprint features, reduces the difficulty in maintenance of multiple documents like authentication data, personnel and diagnosis data, and medical images. The spatial fusion algorithm, which determines the region of embedding using threshold from the image to embed the encrypted patient data, follows the exact rules of fusion resulting in better quality than other fusion techniques. The four step stream cipher algorithm using symmetric key for encrypting the patient data with fingerprint verification system using algebraic invariants improves the robustness of the medical information. The experiment result of proposed scheme is evaluated for security and quality analysis in DICOM medical images resulted well in terms of attacks, quality index, and imperceptibility.

  2. Design features of the radioactive Liquid-Fed Ceramic Melter system

    International Nuclear Information System (INIS)

    Holton, L.K. Jr.

    1985-06-01

    During 1983, the Pacific Northwest Laboratory (PNL), at the request of the Department of Energy (DOE), undertook a program with the principal objective of testing the Liquid-Fed Ceramic Melter (LFCM) process in actual radioactive operations. This activity, termed the Radioactive LFCM (RLFCM) Operations is being conducted in existing shielded hot-cell facilities in B-Cell of the 324 Building, 300 Area, located at Hanford, Washington. This report summarizes the design features of the RLFCM system. These features include: a waste preparation and feed system which uses pulse-agitated waste preparation tanks for waste slurry agitation and an air displacement slurry pump for transferring waste slurries to the LFCM; a waste vitrification system (LFCM) - the design features, design approach, and reasoning for the design of the LFCM are described; a canister-handling turntable for positioning canisters underneath the RLFCM discharge port; a gamma source positioning and detection system for monitoring the glass fill level of the product canisters; and a primary off-gas treatment system for removing the majority of the radionuclide contamination from the RLFCM off gas. 8 refs., 48 figs., 6 tabs

  3. Effects of Food Based Yeast on Oxidant-Antioxidant Systems in Rats fed by High Cholesterol Diet

    OpenAIRE

    Savaş, Hasan Basri; Yüksel, Özlem; Şanlıdere Aloğlu, Hatice; Öner, Zübeyde; Demir Özer, Ezgi; Gültekin, Fatih

    2013-01-01

    In living organisms, oxidant and antioxidant systems are in a balance. In the present study, our aim was to study the effects of Cryptococcus humicola, which is a food based yeast whose cholesterol lowering activity is under investigation, on oxidant and antioxidant systems.31 adult male, Wistar albino rats weighing 200-250 gr were included in the study. Rats were divided into four groups based on their diets. Group 1(Control Group) was fed a normal diet, Group 2 was fed a high cholesterol di...

  4. Simulation and Study of Multilevel Inverter System Fed By Photovoltaic Source

    Directory of Open Access Journals (Sweden)

    Ali Abdulrazzak Jasim

    2018-01-01

    Full Text Available This paper proposes a simulation of Photovoltaic energy used to supply an induction motor with acomparison of two types of inverters.In general, the greater number of motorswhich"are used incommercial and industrial applicationsare"induction motors. To use PV source to run the induction motor, an interface circuits are used which are a dc-dc"converter and an inverter, the PV cell has nonlinear behavior,"adc-dc converter is used along with Maximum Power Point Tracker controllerto improve theefficiency by boosting the output voltage of the PV module and to match the load demand."The dc output voltage of PV modulethen"converted to AC, two types of inverter are presented, A conventional Voltage Source Inverter system and multilevel inverter system which employselective harmonic eliminationmethod fed three phase induction motor, these two types of inverters are simulated using Matlab/Simulink and their results are presented. The FFT spectrum is presented of the output currents to analyze the harmonics reduction, which shows that the"multilevel inverter is better than VSI system"according to harmonics reduction and increment in output voltage and power.

  5. A Condensed Introduction to the Doubly Fed Induction Generator Wind Energy Conversion Systems

    Directory of Open Access Journals (Sweden)

    Julius Mwaniki

    2017-01-01

    Full Text Available The increase in wind power penetration, at 456 GW as of June 2016, has resulted in more stringent grid codes which specify that the wind energy conversion systems (WECS must remain connected to the system during and after a grid fault and, furthermore, must offer grid support by providing reactive currents. The doubly fed induction generator (DFIG WECS is a well-proven technology, having been in use in wind power generation for many years and having a large world market share due to its many merits. Newer technologies such as the direct drive gearless permanent magnet synchronous generator have come up to challenge its market share, but the large number of installed machines ensures that it remains of interest in the wind industry. This paper presents a concise introduction of the DFIG WECS covering its construction, operation, merits, demerits, modelling, control types, levels and strategies, faults and their proposed solutions, and, finally, simulation. Qualities for the optimal control strategy are then proposed. The paper is intended to cover major issues related to the DFIG WECS that are a must for an overview of the system and hence serve as an introduction especially for new entrants into this area of study.

  6. Nisin production of Lactococcus lactis N8 with hemin-stimulated cell respiration in fed-batch fermentation system.

    Science.gov (United States)

    Kördikanlıoğlu, Burcu; Şimşek, Ömer; Saris, Per E J

    2015-01-01

    In this study, nisin production of Lactococcus lactis N8 was optimized by independent variables of glucose, hemin and oxygen concentrations in fed-batch fermentation in which respiration of cells was stimulated with hemin. Response surface model was able to explain the changes of the nisin production of L. lactis N8 in fed-batch fermentation system with high fidelity (R(2) 98%) and insignificant lack of fit. Accordingly, the equation developed indicated the optimum parameters for glucose, hemin, and dissolved oxygen were 8 g L(-1) h(-1) , 3 μg mL(-1) and 40%, respectively. While 1711 IU mL(-1) nisin was produced by L. lactis N8 in control fed-batch fermentation, 5410 IU mL(-1) nisin production was achieved within the relevant optimum parameters where the respiration of cell was stimulated with hemin. Accordingly, nisin production was enhanced 3.1 fold in fed-batch fermentation using hemin. In conclusion the nisin production of L. lactis N8 was enhanced extensively as a result of increasing the biomass by stimulating the cell respiration with adding the hemin in the fed-batch fermentation. © 2015 American Institute of Chemical Engineers.

  7. A Novel Dual-input Isolated Current-Fed DC-DC Converter for Renewable Energy System

    DEFF Research Database (Denmark)

    Zhang, Zhe; Thomsen, Ole Cornelius; Andersen, Michael A. E.

    2010-01-01

    In this paper, a novel isolated current-fed DC-DC converter (boost-type) with two input power sources based on multi-transformer structure, which is suitable for fuel cells and super-capacitors hybrid energy system, is proposed and designed. With particular transformer windings connection strategy...

  8. Modeling and Simulation of Generator Side Converter of Doubly Fed Induction Generator-Based Wind Power Generation System

    DEFF Research Database (Denmark)

    Guo, Yougui; Zeng, Ping; Blaabjerg, Frede

    2010-01-01

    A real wind power generation system is given in this paper. SVM control strategy and vector control is applied for generator side converter and doubly fed induction generator respectively. First the mathematical models of the wind turbine rotor, drive train, generator side converter are described...

  9. A Concise Presentation of Doubly Fed Induction Generator Wind Energy Conversion Systems Challenges and Solutions

    Directory of Open Access Journals (Sweden)

    Julius Mwaniki

    2017-01-01

    Full Text Available There is increased worldwide wind power generation, a large percentage of which is grid connected. The doubly fed induction generator (DFIG wind energy conversion system (WECS has many merits and, as a result, large numbers have been installed to date. The DFIG WECS operation, under both steady state and fault conditions, is of great interest since it impacts on grid performance. This review paper presents a condensed look at the various applied solutions to the challenges of the DFIG WECS including maximum power point tracking, common mode voltages, subsynchronous resonance, losses, modulation, power quality, and faults both internal and from the grid. It also looks at approaches used to meet the increasingly stringent grid codes requirements for the DFIG WECS to not only ride through faults but also provide voltage support. These are aspects of the DFIG WECS that are critical for system operators and prospective investors and can also serve as an introduction for new entrants into this area of study.

  10. Induced bioelectrochemical metabolism for bioremediation of petroleum refinery wastewater: Optimization of applied potential and flow of wastewater.

    Science.gov (United States)

    Mohanakrishna, Gunda; Al-Raoush, Riyadh I; Abu-Reesh, Ibrahim M

    2018-07-01

    Hybrid based bioelectrochemical system (BES) configured with embedded anode and cathode electrodes in soil was tested for the bioelectrochemical degradation of petroleum refinery wastewater (PRW). Four applied potentials were studied to optimize under batch mode operation, among which 2 V resulted in higher COD degradation (69.2%) and power density (725 mW/m 2 ) during 7 days of operation. Further studies with continuous mode of operation at optimized potential (2 V) showed that hydraulic retention time (HRT) of 19 h achieved the highest COD removal (37%) and highest power density (561 mW/m 2 ). BES function with respect to treatment efficiencies of other pollutants of PRW was also identified with respect to oil and grease (batch mode, 91%; continuous mode, 34%), total dissolved salts (batch mode, 53%; continuous mode, 24%) and sulfates (batch mode, 59%; continuous mode, 42%). Soil microenvironment in association with BES forms complex processes, providing suitable conditions for efficient treatment of PRW. Copyright © 2018 Elsevier Ltd. All rights reserved.

  11. In Vivo Dissolution and Systemic Absorption of Immediate Release Ibuprofen in Human Gastrointestinal Tract under Fed and Fasted Conditions.

    Science.gov (United States)

    Koenigsknecht, Mark J; Baker, Jason R; Wen, Bo; Frances, Ann; Zhang, Huixia; Yu, Alex; Zhao, Ting; Tsume, Yasuhiro; Pai, Manjunath P; Bleske, Barry E; Zhang, Xinyuan; Lionberger, Robert; Lee, Allen; Amidon, Gordon L; Hasler, William L; Sun, Duxin

    2017-12-04

    In vivo drug dissolution in the gastrointestinal (GI) tract is largely unmeasured. The purpose of this clinical study was to evaluate the in vivo drug dissolution and systemic absorption of the BCS class IIa drug ibuprofen under fed and fasted conditions by direct sampling of stomach and small intestinal luminal content. Expanding current knowledge of drug dissolution in vivo will help to establish physiologically relevant in vitro models predictive of drug dissolution. A multilumen GI catheter was orally inserted into the GI tract of healthy human subjects. Subjects received a single oral dose of ibuprofen (800 mg tablet) with 250 mL of water under fasting and fed conditions. The GI catheter facilitated collection of GI fluid from the stomach, duodenum, and jejunum. Ibuprofen concentration in GI fluid supernatant and plasma was determined by LC-MS/MS. A total of 23 subjects completed the study, with 11 subjects returning for an additional study visit (a total of 34 completed study visits). The subjects were primarily white (61%) and male (65%) with an average age of 30 years. The subjects had a median [min, max] weight of 79 [52, 123] kg and body mass index of 25.7 [19.4, 37.7] kg/m 2 . Ibuprofen plasma levels were higher under fasted conditions and remained detectable for 28 h under both conditions. The AUC 0-24 and C max were lower in fed subjects vs fasted subjects, and T max was delayed in fed subjects vs fasted subjects. Ibuprofen was detected immediately after ingestion in the stomach under fasting and fed conditions until 7 h after dosing. Higher levels of ibuprofen were detected in the small intestine soon after dosing in fasted subjects compared to fed. In contrast to plasma drug concentration, overall gastric concentrations remained higher under fed conditions due to increased gastric pH vs fasting condition. The gastric pH increased to near neutrality after feedingbefore decreasing to acidic levels after 7 h. Induction of the fed state reduced systemic

  12. Titanium tungsten coatings for bioelectrochemical applications

    DEFF Research Database (Denmark)

    Wierzbicki, Rafal; Amato, Letizia; Łopacińska, J.

    2011-01-01

    This paper presents an assessment of titanium tungsten (TiW) coatings and their applicability as components of biosensing systems. The focus is put on using TiW as an electromechanical interface layer between carbon nanotube (CNT) forests and silicon nanograss (SiNG) cell scaffolds. Cytotoxicity......, applicability to plasma-enhanced chemical vapor deposition (PECVD) of aligned CNT forests, and electrochemical performance are investigated. Experiments include culturing of NIH3T3 mouse embryonic fibroblast cells on TiW coated silicon scaffolds, CNT growth on TiW substrates with nickel catalyst, and cyclic...

  13. Pump-Fed, Compact, High Performance Green Propulsion System for Secondary Payloads, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — Flight Works is proposing to expand its micropump-fed propulsion technology to the development of a low cost, compact, low tank pressure, high performance LPM-103S...

  14. Detailed Transients Simulation of a Doubly Fed Induction Generator Wind Turbine System with the EMTP-Type OVNI Simulator

    OpenAIRE

    Lukić Armstrong, Mažana; R. Martí, José; Kundur, Prabha

    2017-01-01

    Doubly fed induction generator wind turbines are increasingly used in new wind turbine installations all over the world. Growing concerns about the impact of a large number of these generators on transient and voltage stability of power system networks has led engineers to revisit modelling and simulation practices used for system stability analyses. In this paper, the latest advancements in design of the general purpose power system simulator OVNI developed at the University o...

  15. Harmonic Instability Assessment Using State-Space Modeling and Participation Analysis in Inverter-Fed Power Systems

    DEFF Research Database (Denmark)

    Wang, Yanbo; Wang, Xiongfei; Blaabjerg, Frede

    2017-01-01

    parameters on the harmonic instability of the power system. Moreover, the harmonic-frequency oscillation modes are identified, where participation analysis is presented to evaluate the contributions of different states to these modes and to further reveal how the system gives rise to harmonic instability......This paper presents a harmonic instability analysis method using state-space modeling and participation analysis in the inverter-fed ac power systems. A full-order state-space model for the droop-controlled Distributed Generation (DG) inverter is built first, including the time delay of the digital...... control system, inner current and voltage control loops, and outer droop-based power control loop. Based on the DG inverter model, an overall state-space model of a two-inverter-fed system is established. The eigenvalue-based stability analysis is then presented to assess the influence of controller...

  16. Synthesis and bioelectrochemical behavior of aromatic amines.

    Science.gov (United States)

    Shabbir, Muhammad; Akhter, Zareen; Ahmad, Iqbal; Ahmed, Safeer; Bolte, Michael; McKee, Vickie

    2017-12-01

    Four aromatic amines 1-amino-4-phenoxybenzene (A 1 ), 4-(4-aminophenyloxy) biphenyl (A 2 ), 1-(4-aminophenoxy) naphthalene (A 3 ) and 2-(4-aminophenoxy) naphthalene (A 4 ) were synthesized and characterized by elemental, spectroscopic (FTIR, NMR), mass spectrometric and single crystal X-ray diffraction methods. The compounds crystallized in monoclinic crystal system with space group P2 1 . Intermolecular hydrogen bonds were observed between the amine group and amine/ether acceptors of neighboring molecules. Electrochemical investigations were done using cyclic voltammetry (CV), square wave voltammetry (SWV) and differential pulse voltammetry (DPV). CV studies showed that oxidation of aromatic amines takes place at about 0.9 V (vs. Ag/AgCl) and the electron transfer (ET) process has irreversible nature. After first scan reactive intermediate were generated electrochemically and some other cathodic and anodic peaks also appeared in the succeeding scans. DPV study revealed that ET process is accompanied by one electron. DNA binding study of aromatic amines was performed by CV and UV-visible spectroscopy. These investigations revealed groove binding mode of interaction of aromatic amines with DNA. Copyright © 2017 Elsevier Inc. All rights reserved.

  17. A Multiband Proximity-Coupled-Fed Flexible Microstrip Antenna for Wireless Systems

    Directory of Open Access Journals (Sweden)

    Giovanni Andrea Casula

    2016-01-01

    Full Text Available A multiband printed microstrip antenna for wireless communications is presented. The antenna is fed by a proximity-coupled microstrip line, and it is printed on a flexible substrate. The antenna has been designed using a general-purpose 3D computer-aided design software (CAD, CST Microwave Studio, and then realized. The comparison between simulated and measured results shows that the proposed antenna can be used for wireless communications for WLAN systems, covering both the WLAN S-band (2.45 GHz and C-band (5.2 GHz, and the Wi-Max 3.5 GHz band, with satisfactory input matching and broadside radiation pattern. Moreover, it has a compact size, is very easy to realize, and presents a discrete out-of-band rejection, without requiring the use of stop-band filters. The proposed structure can be used also as a conformal antenna, and its frequency response and radiated field are satisfactory for curvatures up to 65°.

  18. A new nordic structure evaluation system for diets fed to dairy cows

    DEFF Research Database (Denmark)

    Nørgaard, Peder; Nadeau, E.; Randby, Å.T.

    2010-01-01

    , and with studies as random effect for ruminating time. The mRTf value per kg forage NDF decreased at increased BW and DNFIf/BW. The mETf value increased at increasing BW and at decreasing DM contents of grass silage. Intake of NDF from rolled barley stimulated ruminating time by 3/4 of the stimuli from DNFIf......The overall aim was to establish a model for predicting chewing index (CI) values for ranking the fibrousnesses of feeds fed to dairy cows within the Nordic Chewing index system. The CI values are predicted as the sum of the eating (EI) and ruminating time index (RI) values. The EI values...... are assumed to be proportional with the NDF content and a particle size factor through the porportionality factor kEI. The RI values are assumed to be proportional with the NDF content, a particle size factor and a hardness factor through the proportionality factor kRI. The kEI, kRI values and the k...

  19. Effects of voltage unbalance and system harmonics on the performance of doubly fed induction wind generators

    Science.gov (United States)

    Kiani, Morgan Mozhgan

    Inherent difficulties in management of electric power in the presence of an increasing demand for more energy, non-conventional loads such as digital appliances, and non-sustainable imported fossil fuels has initiated a multi-folded effort by many countries to restructure the way electric energy is generated, dispatched, and consumed. Smart power grid is the manifestation of many technologies that would eventually transforms the existing power grid into a more flexible, fault resilient, and intelligent system. Integration of distributed renewable energy sources plays a central role in successful implementation of this transformation. Among the renewable options, wind energy harvesting offers superior engineering and economical incentives with minimal environmental impacts. Doubly fed induction generators (DFIG) have turned into a serious contender for wind energy generators due to their flexibility in control of active and reactive power with minimal silicon loss. Significant presence of voltage unbalance and system harmonics in finite inertia transmission lines can potentially undermine the reliability of these wind generators. The present dissertation has investigated the impacts of system unbalances and harmonics on the performance of the DFIG. Our investigation indicates that these effects can result in an undesirable undulation in the rotor shaft which can potentially invoke mechanical resonance, thereby causing catastrophic damages to the installations and the power grid. In order to remedy the above issue, a control solution for real time monitoring of the system unbalance and optimal excitation of the three phase rotor currents in a DFIG is offered. The optimal rotor currents will create appropriate components of the magneto-motive force in the airgap that will actively compensate the undesirable magnetic field originated by the stator windings. Due to the iterative nature of the optimization procedure, field reconstruction method has been incorporated

  20. System and method to control h2o2 level in advanced oxidation processes

    DEFF Research Database (Denmark)

    2016-01-01

    The present invention relates to a bio-electrochemical system (BES) and a method of in-situ production and removal of H2O2 using such a bio-electrochemical system (BES). Further, the invention relates to a method for in-situ control of H2O2 content in an aqueous system of advanced oxidation...

  1. Contents and risks of potentially toxic elements in wastewater-fed food production systems in Southeast Asia

    DEFF Research Database (Denmark)

    Marcussen, Helle

    , fish, soil and sediment from wastewater-fed production systems in Hanoi and Phnom Penh. Another aim was to assess the food safety risks of water spinach and fish with respect to PTEs. The third aim was to assess PTE retention capacity of river sediment in Hanoi and the governing retention mechanisms...... the concentration range observed for water spinach grown at agricultural soil not exposed to wastewater in Malaysia. Water spinach grown at sites of high and low wastewater exposure did not show a significantly higher accumulation of PTEs compared to sites without wastewater exposure. In Phnom Penh, water spinach...... than 11% of the tolerable intake for each element. The PTE content of water spinach in Hanoi and Cheung Ek Lake in Phnom Penh constituted low food safety risks for consumers. Arsenic, Cd and Pb concentrations in muscle, skin and liver of fish grown in wastewater-fed systems in Hanoi and Phnom were low...

  2. Bidirectional DC-DC converter fed drive for electric vehicle system ...

    African Journals Online (AJOL)

    Batteries are the primary energy-storage devices in ground vehicles. Now days battery fed electric drives are commonly being used for electric vehicles applications, due to various advantages, such as: nearly zero emission, guaranteed load leveling, good transient operation and energy recovery during braking operation.

  3. Thermal Behavior of Doubly-Fed Induction Generator Wind Turbine System during Balanced Grid Fault

    DEFF Research Database (Denmark)

    Zhou, Dao; Blaabjerg, Frede; Lau, Mogens

    2014-01-01

    Ride-through capabilities of the doubly-fed induction generator (DFIG) during grid fault have been studied a lot. However, the thermal performance of the power device during this transient period is seldom investigated. In this paper, the dynamic model for the DFIG and the influence of the rotor...

  4. Degradation of chlorophenol mixtures in a fed-batch system by two ...

    African Journals Online (AJOL)

    2010-12-16

    Dec 16, 2010 ... water is fed to the biological treatment unit either intermittently or ... the same culture in a binary mixture and in ternary mixture of 2,4,6TCP; 2,3,5 .... Solving the balance equation (Eq. (2)) with the initial condi- tions of the ...

  5. Carbon and Nitrogen Sources for Shrimp Postlarvae Fed Natural Diets from a Tropical Mangrove System

    Science.gov (United States)

    Dittel, A. I.; Epifanio, C. E.; Cifuentes, L. A.; Kirchman, D. L.

    1997-11-01

    Postlarvae ofPenaeus vannameiwere fed various diets in order to examine the importance of detritus and other possible prey items in supporting postlarval growth. Stable isotopes (C and N) were used to determine the carbon and nitrogen source of the prey in the various diets. The zooplankton diet contained mostly copepods. The subtidal detritus treatment consisted mostly of plant material whereas the diets from both intertidal sites contained a mixture of plant detritus and associated meiofauna. Postlarvae reared on zooplankton and detritus plus meiofauna diets more than tripled their weight during a 6-day period. In contrast, postlarvae fed the detritus diet barely doubled their weight. Based on isotopic composition, postlarvae appear to obtain their carbon and nitrogen from various food sources. Postlarvae were enriched by 0·4‰ in13C and 2·7‰ in15N relative to the zooplankton diet, which is consistent with isotopic fractionation between successive trophic levels. In turn, the isotopic signal of the zooplankton was consistent with phytoplankton being the initial source of organic matter. In contrast, mean δ13C values of the shrimp fed detritus plus meiofauna were significantly different from their respective diets. Isotopic ratios of the postlarvae fed the mixed diet from Chomes were two trophic levels above benthic algae suggesting that the shrimp preyed on organisms that derived their carbon and nitrogen from benthic algae and/or phytoplankton.

  6. Is the Grass Always Greener? Comparing the Environmental Impact of Conventional, Natural and Grass-Fed Beef Production Systems

    Directory of Open Access Journals (Sweden)

    Judith L. Capper

    2012-04-01

    Full Text Available This study compared the environmental impact of conventional, natural and grass-fed beef production systems. A deterministic model based on the metabolism and nutrient requirements of the beef population was used to quantify resource inputs and waste outputs per 1.0 × 109 kg of hot carcass weight beef in conventional (CON, natural (NAT and grass-fed (GFD production systems. Production systems were modeled using characteristic management practices, population dynamics and production data from U.S. beef production systems. Increased productivity (slaughter weight and growth rate in the CON system reduced the cattle population size required to produce 1.0 × 109 kg of beef compared to the NAT or GFD system. The CON system required 56.3% of the animals, 24.8% of the water, 55.3% of the land and 71.4% of the fossil fuel energy required to produce 1.0 × 109 kg of beef compared to the GFD system. The carbon footprint per 1.0 × 109 kg of beef was lowest in the CON system (15,989 × 103 t, intermediate in the NAT system (18,772 × 103 t and highest in the GFD system (26,785 × 103 t. The challenge to the U.S beef industry is to communicate differences in system environmental impacts to facilitate informed dietary choice.

  7. Micro-coulometric study of bioelectrochemical reaction coupled with TCA cycle.

    Science.gov (United States)

    Tsujimura, Seiya; Fukuda, Jun; Shirai, Osamu; Kano, Kenji; Sakai, Hideki; Tokita, Yuichi; Hatazawa, Tsuyonobu

    2012-04-15

    The mediated electro-enzymatic electrolysis systems based on the tricarboxylic acid (TCA) cycle reaction were examined on a micro-bulk electrolytic system. A series of the enzyme-catalyzed reactions in the TCA cycle was coupled with electrode reaction. Electrochemical oxidation of NADH was catalyzed by diaphorase with an aid of a redox mediator with a formal potential of -0.15 V vs. Ag|AgCl. The mediator was also able to shuttle electrons between succinate dehydrogenase and electrode. The charge during the electrolysis increased on each addition of dehydrogenase reaction in a cascade of the TCA cycle. However, the electrolysis efficiencies were close to or less than 90% because of the product inhibition. Lactate oxidation to acetyl-CoA catalyzed by two NAD-dependent dehydrogenases was coupled with the bioelectrochemical TCA cycle reaction to achieve the 12-electron oxidation of lactate to CO(2). The charge passed in the bioelectrocatalytic oxidation of 5 nmol of lactate was 4 mC, which corresponds to 70% of the electrolysis efficiency. Copyright © 2012 Elsevier B.V. All rights reserved.

  8. Design and dynamic simulation of a novel polygeneration system fed by vegetable oil and by solar energy

    International Nuclear Information System (INIS)

    Calise, Francesco; Palombo, Adolfo; Vanoli, Laura

    2012-01-01

    Highlights: ► A novel polygeneration system based on engines (RE) fed by rapeseed oil is investigated. ► RE are integrated with high temperature solar heating and cooling systems. ► The polygeneration system is dynamically investigated for a Mediterranean Climate. ► System performance is excellent from the energetic point of view. ► The system is economically profitable only in case of feed-in tariffs. - Abstract: In this paper the integration of vegetable oil-fed reciprocating engines with solar thermal collector is investigated, seeking to design a novel polygeneration system producing: electricity, space heating and cooling and domestic hot water, for a university building located in Naples (Italy), assumed as case study. The polygeneration system is based on the following main components: concentrating parabolic trough solar collector, double-stage LiBr–H 2 O absorption chiller and a reciprocating engine fed by vegetable oil. The engine operates at full load producing electrical energy which is in part consumed by the building lights and equipments, in part used by the system passive loads and the rest is eventually sold to the grid. In fact, the engine is grid connected in order to perform a convenient net metering. The system was designed and then simulated by means of a zero-dimensional transient simulation model, developed using the TRNSYS software. The simulation tool developed by the authors allows one to analyze the results for different time basis (minutes, days, weeks, months and years), from both energetic and economic points of view. The economic results show that the system under investigation is profitable, especially if properly funded.

  9. Graphene oxide and H2 production from bioelectrochemical graphite oxidation.

    Science.gov (United States)

    Lu, Lu; Zeng, Cuiping; Wang, Luda; Yin, Xiaobo; Jin, Song; Lu, Anhuai; Jason Ren, Zhiyong

    2015-11-17

    Graphene oxide (GO) is an emerging material for energy and environmental applications, but it has been primarily produced using chemical processes involving high energy consumption and hazardous chemicals. In this study, we reported a new bioelectrochemical method to produce GO from graphite under ambient conditions without chemical amendments, value-added organic compounds and high rate H2 were also produced. Compared with abiotic electrochemical electrolysis control, the microbial assisted graphite oxidation produced high rate of graphite oxide and graphene oxide (BEGO) sheets, CO2, and current at lower applied voltage. The resultant electrons are transferred to a biocathode, where H2 and organic compounds are produced by microbial reduction of protons and CO2, respectively, a process known as microbial electrosynthesis (MES). Pseudomonas is the dominant population on the anode, while abundant anaerobic solvent-producing bacteria Clostridium carboxidivorans is likely responsible for electrosynthesis on the cathode. Oxygen production through water electrolysis was not detected on the anode due to the presence of facultative and aerobic bacteria as O2 sinkers. This new method provides a sustainable route for producing graphene materials and renewable H2 at low cost, and it may stimulate a new area of research in MES.

  10. Bioelectrochemical reduction of volatile fatty acids in anaerobic digestion effluent for the production of biofuels.

    Science.gov (United States)

    Kondaveeti, Sanath; Min, Booki

    2015-12-15

    This study proves for the first time the feasibility of biofuel production from anaerobic digestion effluent via bioelectrochemical cell operation at various applied cell voltages (1.0, 1.5 and 2.0 V). An increase in cell voltage from 1 to 2 V resulted in more reduction current generation (-0.48 to -0.78 mA) at a lowered cathode potential (-0.45 to -0.84 mV vs Ag/AgCl). Various alcohols were produced depending on applied cell voltages, and the main products were butanol, ethanol, and propanol. Hydrogen and methane production were also observed in the headspace of the cell. A large amount of lactic acid was unexpectedly formed at all conditions, which might be the primary cause of the limited biofuel production. The addition of neutral red (NR) to the system could increase the cathodic reduction current, and thus more biofuels were produced with an enhanced alcohol formation compared to without a mediator. Copyright © 2015 Elsevier Ltd. All rights reserved.

  11. Improving Energy Efficiency and Enabling Water Recycle in Biorefineries Using Bioelectrochemical Cells

    International Nuclear Information System (INIS)

    Borole, Abhijeet P.

    2010-01-01

    Improving biofuel yield and water reuse are two important issues in further development of biorefineries. The total energy content of liquid fuels (including ethanol and hydrocarbon) produced from cellulosic biomass via biochemical or hybrid bio-thermochemical routes can vary from 49% to 70% of the biomass entering the biorefinery, on an energy basis. Use of boiler for combustion of residual organics and lignin results in significant energy and water losses. An alternate process to improve energy recovery from the residual organic streams is via use of bioelectrochemical systems such as microbial fuel cells (MFCs) microbial electrolysis cells (MECs). The potential advantages of this alternative scheme in a biorefinery include minimization of heat loss and generation of a higher value product, hydrogen. The need for 5-15 gallons of water per gallon of ethanol can be reduced significantly via recycle of water after MEC treatment. Removal of inhibitory byproducts such as furans, phenolics and acetate in MFC/MECs to generate energy, thus, has dual advantages including improvements in energy efficiency and ability to recycle water. Conversion of the sugar- and lignin- degradation products to hydrogen is synergistic with biorefinery hydrogen requirements for upgrading F-T liquids and other byproducts to high-octane fuels and/or high value products. Some of these products include sorbitol, succinic acid, furan and levulinate derivatives, glycols, polyols, 1,4-butenadiol, phenolics polymers, etc. Potential process alternatives utilizing MECs in biorefineries capable of improving energy efficiency by up to 30% are discussed.

  12. Bioelectrochemical BTEX removal at different voltages: assessment of the degradation and characterization of the microbial communities.

    Science.gov (United States)

    Daghio, Matteo; Espinoza Tofalos, Anna; Leoni, Barbara; Cristiani, Pierangela; Papacchini, Maddalena; Jalilnejad, Elham; Bestetti, Giuseppina; Franzetti, Andrea

    2018-01-05

    BTEX compounds (Benzene, Toluene, Ethylbenzene and Xylenes) are toxic hydrocarbons that can be found in groundwater due to accidental spills. Bioelectrochemical systems (BES) are an innovative technology to stimulate the anaerobic degradation of hydrocarbons. In this work, single chamber BESs were used to assess the degradation of a BTEX mixture at different applied voltages (0.8V, 1.0V, 1.2V) between the electrodes. Hydrocarbon degradation was linked to current production and to sulfate reduction, at all the tested potentials. The highest current densities (about 200mA/m 2 with a maximum peak at 480mA/m 2 ) were observed when 0.8V were applied. The application of an external voltage increased the removal of toluene, m-xylene and p-xylene. The highest removal rate constants at 0.8V were: 0.4±0.1days -1 , 0.34±0.09days -1 and 0.16±0.02days -1 , respectively. At the end of the experiment, the microbial communities were characterized by high throughput sequencing of the 16S rRNA gene. Microorganisms belonging to the families Desulfobulbaceae, Desulfuromonadaceae and Geobacteraceae were enriched on the anodes suggesting that both direct electron transfer and sulfur cycling occurred. The cathodic communities were dominated by the family Desulfomicrobiaceae that may be involved in hydrogen production. Copyright © 2017 Elsevier B.V. All rights reserved.

  13. Plant Performance of Solid Oxide Fuel Cell Systems Fed by Alternative Fuels

    DEFF Research Database (Denmark)

    Rokni, Masoud

    2016-01-01

    Different plant design for several fuel types such as natural gas, methanol, ethanol, DME, ammonia and pure hydrogen are presented and analysed. Anode recirculation which is an important issue in SOFC plants are also explored and studied. It is shown that depending on type of the fuel whether fuel...... recycle increases plant efficiency only if fuel utilization factor is low. Other important issues such as why plant efficiency is lower when it is fed with hydrogen or biogas compared to when it is fed by other fuels such as methanol, ethanol, DME and ammonia will also be discussed and explained....... For example, plant efficiency of 45%, 54% and 50.5% can be achieved if the hydrogen, ethanol and methanol are used respectively....

  14. CONVERSION OF PINEAPPLE JUICE WASTE INTO LACTIC ACID IN BATCH AND FED – BATCH FERMENTATION SYSTEMS

    Directory of Open Access Journals (Sweden)

    Abdullah Mochamad Busairi

    2012-01-01

    Full Text Available Pineapple juice waste contains valuable components, which are mainly sucrose, glucose, and fructose. Recently, lactic acid has been considered to be an important raw material for the production of biodegradable lactide polymer. The fermentation experiments were carried out in a 3 litres fermentor (Biostat B Model under anaerobic condition with stirring speed of 50 rpm, temperature at 40oC, and pH of 6.00. Effect of feed concentration on lactic acid production, bacterial growth, substrate utilisation and productivity was studied. The results obtained from fed- batch culture fermentation showed that the maximum lactic acid productivity was 0.44 g/L.h for feed concentration of 90 g/L at 48 hours. Whereas the lactic acid productivity obtained from fed-batch culture was twice and half fold higher than that of batch culture productivity.  Buangan jus nanas mengandung komponen yang berharga terutama sukrosa, glukosa, dan fruktosa. Asam laktat adalah bahan baku yang terbaru dan penting untuk dibuat sebagai polimer laktat yang dapat terdegradasi oleh lingkungan. Percobaan dilakukan pada fermentor 3 liter (Model Biostat B di bawah kondisi anaerob dengan kecepatan pengadukan 50 rpm, temperatur 40oC, dan pH 6,00. Pengaruh konsentrasi umpan terhadap produksi asam laktat, pertumbuhan mikroba, pengggunaan substrat dan produktivitas telah dipelajari. Hasil yang didapatkan pada fermentasi dengan menggunakan sistem fed-batch menunjukkan bahwa produktivitas asam laktat maksimum adalah 0.44 g/L,jam dengan konsentrasi umpan, 90 g/L pada waktu 48 jam. Bahkan produktivitas asam laktat yang didapat pada kultur fed-batch lebih tinggi 2,5 kali dari pada proses menggunakan sistem batch

  15. Degradation of chlorophenol mixtures in a fed-batch system by two ...

    African Journals Online (AJOL)

    This work was undertaken to investigate the effect of variations of the feed rate on a fed-batch set-up used to degrade xenobiotics. The mixture of substrates was composed of PCP, 2,4,6 TCP and 2,3,5,6 TeCP (pentachlorophenol, 2,4,6 trichlorophenol and 2,3,5,6 tetrachlorophenol respectively). Two acclimated bacteria ...

  16. A Flywheel Energy Storage System Based on a Doubly Fed Induction Machine and Battery for Microgrid Control

    Directory of Open Access Journals (Sweden)

    Thai-Thanh Nguyen

    2015-06-01

    Full Text Available Microgrids are eco-friendly power systems because they use renewable sources such as solar and wind power as the main power source. However, the stochastic nature of wind and solar power is a considerable challenge for the efficient operation of microgrids. Microgrid operations have to satisfy quality requirements in terms of the frequency and voltage. To overcome these problems, energy storage systems for short- and long-term storage are used with microgrids. Recently, the use of short-term energy storage systems such as flywheels has attracted significant interest as a potential solution to this problem. Conventional flywheel energy storage systems exhibit only one control mode during operation: either smoothing wind power control or frequency control. In this paper, we propose a new flywheel energy storage system based on a doubly fed induction machine and a battery for use with microgrids. The new flywheel energy storage system can be used not only to mitigate wind power fluctuations, but also to control the frequency as well as the voltage of the microgrid during islanded operation. The performance of the proposed flywheel energy storage system is investigated through various simulations using MATLAB/Simulink software. In addition, a conventional flywheel energy storage system based on a doubly fed induction machine is simulated and its performance compared with that of the proposed one.

  17. Nitrate remediation in a novel upflow bio-electrochemical reactor (UBER) using palm shell activated carbon as cathode material

    International Nuclear Information System (INIS)

    Ghafari, Shahin; Hasan, Masitah; Aroua, Mohamed Kheireddine

    2009-01-01

    This study investigated the biological denitrification method which is a treatment method able to reduce inorganic nitrate compounds to harmless nitrogen gas. Autohydrogenotrophic denitrifying bacteria were used in this study to prevent any problematic outcomes associated with heterotrophic microorganisms. An upflow bio-electrochemical reactor (UBER) was used to accommodate hydrogenotrophic denitrifying bacteria employing palm shell granular activated carbon (GAC) as the biocarrier and cathode material. Bicarbonate as the external inorganic carbon source was fed to the reactor and hydrogen as the electron donor was generated in situ through electrolysis of water. Central composite design (CCD) and response surface methodology (RSM) were applied to investigate the effects of two operating parameters, namely electric current (I) and hydraulic retention time (HRT), on performance of the UBER. Electric current range of 0-20 mA and HRT range of 6-36 h were examined and results showed that nitrate can be entirely reduced within application of a wide operational range of electric current (10-16 mA) as well as HRT (13.5-30 h). However, increase of pH at cathode zone up to 10.5 inhibited nitrite reduction, and it was not reduced to the satisfactory level.

  18. Exercise training modulates the hepatic renin-angiotensin system in fructose-fed rats.

    Science.gov (United States)

    Frantz, Eliete Dalla Corte; Medeiros, Renata Frauches; Giori, Isabele Gomes; Lima, Juliana Bittencourt Silveira; Bento-Bernardes, Thais; Gaique, Thaiane Gadioli; Fernandes-Santos, Caroline; Fernandes, Tiago; Oliveira, Edilamar Menezes; Vieira, Carla Paulo; Conte-Junior, Carlos Adam; Oliveira, Karen Jesus; Nobrega, Antonio Claudio Lucas

    2017-09-01

    What is the central question of this study? What are the effects of exercise training on the hepatic renin-angiotensin system and their contribution to damage resulting from fructose overload in rats? What is the main finding and its importance? Exercise training attenuated the deleterious actions of the angiotensin-converting enzyme/angiotensin II/angiotensin II type 1 receptor axis and increased expression of the counter-regulatory (angiotensin-converting enzyme 2/angiotensin (1-7)/Mas receptor) axis in the liver. Therefore, our study provides evidence that exercise training modulates the hepatic renin-angiotensin system, which contributes to reducing the progression of metabolic dysfunction and non-alcoholic fatty liver disease in fructose-fed rats. The renin-angiotensin system (RAS) has been implicated in the development of metabolic syndrome. We investigated whether the hepatic RAS is modulated by exercise training and whether this modulation improves the deleterious effects of fructose overload in rats. Male Wistar rats were divided into (n = 8 each) control (CT), exercise control (CT-Ex), high-fructose (HFr) and exercise high-fructose (HFr-Ex) groups. Fructose-drinking rats received d-fructose (100 g l -1 ). After 2 weeks, CT-Ex and HFr-Ex rats were assigned to a treadmill training protocol at moderate intensity for 8 weeks (60 min day -1 , 4 days per week). We assessed body mass, glucose and lipid metabolism, hepatic histopathology, angiotensin-converting enzyme (ACE) and angiotensin-converting enzyme 2 (ACE2) activity, the angiotensin concentration and the expression profile of proteins affecting the hepatic RAS, gluconeogenesis and inflammation. Neither fructose overload nor exercise training influenced body mass gain and serum ACE and ACE2 activity. The HFr group showed hyperinsulinaemia, but exercise training normalized this parameter. Exercise training was effective in preventing hepatic steatosis and in preventing triacylglycerol and

  19. Exergy Analysis of an Intermediate Temperature Solid Oxide Fuel Cell-Gas Turbine Hybrid System Fed with Ethanol

    Directory of Open Access Journals (Sweden)

    Fotini Tzorbatzoglou

    2012-10-01

    Full Text Available In the present work, an ethanol fed Solid Oxide Fuel Cell-Gas Turbine (SOFC-GT system has been parametrically analyzed in terms of exergy and compared with a single SOFC system. The solid oxide fuel cell was fed with hydrogen produced from ethanol steam reforming. The hydrogen utilization factor values were kept between 0.7 and 1. The SOFC’s Current-Volt performance was considered in the range of 0.1–3 A/cm2 at 0.9–0.3 V, respectively, and at the intermediate operating temperatures of 550 and 600 °C, respectively. The curves used represent experimental results obtained from the available bibliography. Results indicated that for low current density values the single SOFC system prevails over the SOFC-GT hybrid system in terms of exergy efficiency, while at higher current density values the latter is more efficient. It was found that as the value of the utilization factor increases the SOFC system becomes more efficient than the SOFC-GT system over a wider range of current density values. It was also revealed that at high current density values the increase of SOFC operation temperature leads in both cases to higher system efficiency values.

  20. DataFed: A Federated Data System for Visualization and Analysis of Spatio-Temporal Air Quality Data

    Science.gov (United States)

    Husar, R. B.; Hoijarvi, K.

    2017-12-01

    DataFed is a distributed web-services-based computing environment for accessing, processing, and visualizing atmospheric data in support of air quality science and management. The flexible, adaptive environment facilitates the access and flow of atmospheric data from provider to users by enabling the creation of user-driven data processing/visualization applications. DataFed `wrapper' components, non-intrusively wrap heterogeneous, distributed datasets for access by standards-based GIS web services. The mediator components (also web services) map the heterogeneous data into a spatio-temporal data model. Chained web services provide homogeneous data views (e.g., geospatial, time views) using a global multi-dimensional data model. In addition to data access and rendering, the data processing component services can be programmed for filtering, aggregation, and fusion of multidimensional data. A complete application software is written in a custom made data flow language. Currently, the federated data pool consists of over 50 datasets originating from globally distributed data providers delivering surface-based air quality measurements, satellite observations, emissions data as well as regional and global-scale air quality models. The web browser-based user interface allows point and click navigation and browsing the XYZT multi-dimensional data space. The key applications of DataFed are for exploring spatial pattern of pollutants, seasonal, weekly, diurnal cycles and frequency distributions for exploratory air quality research. Since 2008, DataFed has been used to support EPA in the implementation of the Exceptional Event Rule. The data system is also used at universities in the US, Europe and Asia.

  1. Simulation of double-fed speed regulation system for 125 MVA motor-generator set

    International Nuclear Information System (INIS)

    Wang Fen; Wang Shujing; Li Huajun

    2007-01-01

    A simulation modeling of double-fed motor speed regulation for 125 MVA AC pulsed M-G set of HL-2A is built using Matlab. Some parameters of the project are obtained by the pre-simulation, and the process of start-up is analyzed. In the Matlab simulation the motor model in Simulink can not be connected directly to the cycloconverter model. This problem is solved by adding an ideal transformer model between them, and the satisfactory result is obtained. A new method of control switching two cycloconverter without circulating current has been introduced. (authors)

  2. Microbial metabolism and community structure in response to bioelectrochemically enhanced remediation of petroleum hydrocarbon-contaminated soil.

    Science.gov (United States)

    Lu, Lu; Huggins, Tyler; Jin, Song; Zuo, Yi; Ren, Zhiyong Jason

    2014-04-01

    This study demonstrates that electrodes in a bioelectrochemical system (BES) can potentially serve as a nonexhaustible electron acceptor for in situ bioremediation of hydrocarbon contaminated soil. The deployment of BES not only eliminates aeration or supplement of electron acceptors as in contemporary bioremediation but also significantly shortens the remediation period and produces sustainable electricity. More interestingly, the study reveals that microbial metabolism and community structure distinctively respond to the bioelectrochemically enhanced remediation. Tubular BESs with carbon cloth anode (CCA) or biochar anode (BCA) were inserted into raw water saturated soils containing petroleum hydrocarbons for enhancing in situ remediation. Results show that total petroleum hydrocarbon (TPH) removal rate almost doubled in soils close to the anode (63.5-78.7%) than that in the open circuit positive controls (37.6-43.4%) during a period of 64 days. The maximum current density from the BESs ranged from 73 to 86 mA/m(2). Comprehensive microbial and chemical characterizations and statistical analyses show that the residual TPH has a strongly positive correlation with hydrocarbon-degrading microorganisms (HDM) numbers, dehydrogenase activity, and lipase activity and a negative correlation with soil pH, conductivity, and catalase activity. Distinctive microbial communities were identified at the anode, in soil with electrodes, and soil without electrodes. Uncommon electrochemically active bacteria capable of hydrocarbon degradation such as Comamonas testosteroni, Pseudomonas putida, and Ochrobactrum anthropi were selectively enriched on the anode, while hydrocarbon oxidizing bacteria were dominant in soil samples. Results from genus or phylum level characterizations well agree with the data from cluster analysis. Data from this study suggests that a unique constitution of microbial communities may play a key role in BES enhancement of petroleum hydrocarbons

  3. PWM Regulation of Grid-Tied PV System on the Base of Photovoltaic-Fed Diode-Clamped Inverters

    Directory of Open Access Journals (Sweden)

    Oleschuk V.I.

    2015-12-01

    Full Text Available Investigation of grid-tied photovoltaic system on the base of two diode-clamped inverters, controlled by specific algorithms of pulse-width modulation (PWM, has been done. This system includes two strings of photovoltaic panels feeding two diode-clamped inverters. The outputs of inverters are connected with the corresponding windings on the primary side of three-phase transformer, connected with a grid. In order to reduce phase voltage distortion and to increase efficiency of operation of the system, special scheme of control and modulation of inverters has been used, providing minimization of common-mode voltages and voltage waveforms symmetries under different operating conditions. Detailed simulation of processes in this photovoltaic-fed power conversion system has been executed. The results of simulations verify good performance of photovoltaic system regulated in accordance with specific strategy of control and modulation.

  4. Optimal controller design of a doubly fed induction generator wind turbine system for small signal stability enhancement

    DEFF Research Database (Denmark)

    Yang, Lihui; Yang, Guang-Ya; Xu, Zhao

    2010-01-01

    Multi-objective optimal controller design of a doubly-fed induction generator (DFIG) wind turbine system using differential evolution (DE) is presented. A detailed mathematical model of DFIG wind turbine with a closed-loop vector control system is developed. Based on this, objective functions...... and the constraint with DE, respectively. Eigenvalue analysis and time-domain simulations are performed on a single machine infinite bus system as well as a nine-bus multi-machine system with two DFIG wind turbines to illustrate the control performance of the DFIG wind turbine with the optimised controller...... addressing the steady-state stability and dynamic performance at different operating conditions are implemented to optimise the controller parameters of both the rotor and grid-side converters. A superior 1-constraint method and method of adaptive penalties are applied to handle the multi-objective problem...

  5. Pre-conceptual design requirements and system description for FED frame seal welder and cutter

    International Nuclear Information System (INIS)

    Masson, L.S.; Longhurst, G.R.; Watts, K.D.; Williams, S.A.

    1981-03-01

    The Fusion Engineering Device (FED) is being designed in a torus shape using ten removable segments to form the torus geometry. The torus consists of a frame and ten shield assemblies which fit into the frame and are held in place structurally using electrically insulated backing plates. It is then necessary to seal the shield segment to the frame for the assembly to sustain an internal vacuum of 10 -7 torr. This task is intended to be accomplished by welding a frame seal between the frame and the shield segment. An example of this concept is shown. This document covers the equipment requirements and pre-conceptual design description for installing and removing the frame seal

  6. Geobacter anodireducens sp. nov., an exoelectrogenic microbe in bioelectrochemical systems

    KAUST Repository

    Sun, D.; Wang, A.; Cheng, S.; Yates, M.; Logan, B. E.

    2014-01-01

    -spore-forming, non-fermentative and non-motile. Cells were short, curved rods (0.8-1.3 µm long and 0.3 µm in diameter). Growth of strain SD-1(T) was observed at 15-42 °C and pH 6.0-8.5, with optimal growth at 30-35 °C and pH 7. Analysis of 16S rRNA gene sequences

  7. Bioelectrochemical Systems Workshop:Standardized Analyses, Design Benchmarks, and Reporting

    Science.gov (United States)

    2012-01-01

    measured are the measured anode and cathode potentials and Ean and Ecat are the calculated potentials based on the Nernst equation . These calculated...transport (ET), and pH gradient (EΔpH). The overpotentials can be calculated from Equations 1 and 2 (see attachment), where Ean,measured and Ecat...catalytic current (icat) and the limiting current (iL) is described by Equation 3 (see attachment), where n is the number of electrons involved in the

  8. Optimal Set Anode Potentials Vary in Bioelectrochemical Systems

    KAUST Repository

    Wagner, Rachel C.; Call, Douglas F.; Logan, Bruce E.

    2010-01-01

    and current generation improved or only occurred at more negative potentials. This suggests that even with diverse microbial communities, it is primarily the potential of the terminal respiratory proteins used by certain exoelectrogenic bacteria, and to a

  9. Synthetic Klebsiella pneumoniae-Shewanella oneidensis Consortium Enables Glycerol-Fed High-Performance Microbial Fuel Cells.

    Science.gov (United States)

    Li, Feng; Yin, Changji; Sun, Liming; Li, Yuanxiu; Guo, Xuewu; Song, Hao

    2018-05-01

    Microbial fuel cell (MFC) is an eco-friendly bio-electrochemical sys-tem that uses microorganism as biocatalyst to convert biomass into electricity. Glycerol, as a waste in the biodiesel refinery processes, is an appealing substrate for MFC. Nevertheless, glycerol cannot be utilized as carbon source by well-known exoelectrogens such as Shewanella oneidensis. Herein, to generate electricity by rapidly harnessing glycerol, the authors rationally constructed a Klebsiella pneumoniae-Shewanella oneidensis microbial consortium to efficiently harvest electricity from glyc-erol, in which K. pneumoniae converted glycerol into lactate, fed to S. oneidensis as carbon source and electron donor. To improve electricity output, the authors systematically engineered the consortium in terms of carbon flux distribution and efficiency of extracellular electron transfer (EET). To direct more carbon flux to lactate biosynthesis in K. pneumoniae, the authors eliminated the ethanol pathway by knocking out the alcohol dehydrogenase gene (adhE), and enhanced lactate biosynthesis by heterologously expressing a lactate dehydrogen-ase gene (ldhD) from Lactobacillus bulgaricus and a lactate transporter gene (lldP) from Escherichia coli. To facilitate EET between S. oneidensis and anode surfaces, a biosynthetic flavins pathway from Bacillus subtilis is introduced into S. oneidensis. The author further optimized the glycerol concentration, thus S. oneidensis could be continuously fed with lactate synthesized from K. pneumoniae at a constant rate. Our glycerol-fed MFC generated a maximum power density of 19.9 mW/m 2 , significantly higher than that of the wild-type consor-tium. This work suggested that engineering microbial consortia is an effi-cient strategy to expand the spectrum of usable carbon sources and promote electricity power production in MFCs. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  10. [Bio-electrochemical effect on hydrogenotrophic sulfate reduction stimulated by electrical field in the presence of H2 under atmospheric pressure].

    Science.gov (United States)

    Xu, Hui-Wei; Zhang, Xu; Yang, Shan-Shan; Li, Guang-He

    2009-07-15

    Microbial sulfate reduction rate is limited with H2 as electron donor. In order to improve hydrogenotrophic sulfate reduction under normal atmospheric H2 pressure, a bio-electrochemical system with direct current was designed and performed in this study. Results indicates that sulfate reduction rate (SRR) increases with the augment of current intensity under lower current intensity (I electric or magnetic field stimulates the proliferation of sulfate-reducing bacteria (SRB) and the activity of the enzymes. When I is higher than 1.50 mA, the activity of SRB is inhibited, resulting in lower reduction rate compared with that at lower current. If controlling the cathode potential lower than -0.69 V and H2 partial pressure 1.01 x 10(5) Pa, electro-catalytic sulfate reduction process takes place with H2 as reductant in this bio-electrochemical system. However, the overall reduction rate is still lower than that when I = 1.50 mA is applied, and additionally the energy consumption is much higher. Therefore, electric field of low intensity can enhance hydrogenotrophic sulfate reduction in the presence of H2 under atmospheric pressure.

  11. A method for high throughput bioelectrochemical research based on small scale microbial electrolysis cells

    KAUST Repository

    Call, Douglas F.

    2011-07-01

    There is great interest in studying exoelectrogenic microorganisms, but existing methods can require expensive electrochemical equipment and specialized reactors. We developed a simple system for conducting high throughput bioelectrochemical research using multiple inexpensive microbial electrolysis cells (MECs) built with commercially available materials and operated using a single power source. MECs were small crimp top serum bottles (5mL) with a graphite plate anode (92m 2/m 3) and a cathode of stainless steel (SS) mesh (86m 2/m 3), graphite plate, SS wire, or platinum wire. The highest volumetric current density (240A/m 3, applied potential of 0.7V) was obtained using a SS mesh cathode and a wastewater inoculum (acetate electron donor). Parallel operated MECs (single power source) did not lead to differences in performance compared to non-parallel operated MECs, which can allow for high throughput reactor operation (>1000 reactors) using a single power supply. The utility of this method for cultivating exoelectrogenic microorganisms was demonstrated through comparison of buffer effects on pure (Geobacter sulfurreducens and Geobacter metallireducens) and mixed cultures. Mixed cultures produced current densities equal to or higher than pure cultures in the different media, and current densities for all cultures were higher using a 50mM phosphate buffer than a 30mM bicarbonate buffer. Only the mixed culture was capable of sustained current generation with a 200mM phosphate buffer. These results demonstrate the usefulness of this inexpensive method for conducting in-depth examinations of pure and mixed exoelectrogenic cultures. © 2011 Elsevier B.V.

  12. Irradiated mice lose the capacity to 'process' fed antigen for systemic tolerance of delayed-type hypersensitivity

    Energy Technology Data Exchange (ETDEWEB)

    Bruce, M G; Strobel, S; Hanson, D G; Ferguson, A

    1987-12-01

    'Intestinal antigen processing' is a function of the gastro-intestinal tract whereby shortly after an animal has been fed an immunogenic protein antigen, such as ovabumin (OVA), a tolerogenic form of the protein is generated and can be detected in the circulation. The effect of damage to the intestinal epithelium on the processing of OVA has been examined in lethally irradiated mice. Irradiated animals were fed 25 mg OVA and their serum collected 1 h later. When this serum was transferred intraperitoneally into naive recipient mice, this did not induce the typical suppression of systemic delayed-type hypersensitivity. Results were similar when the serum donors were at 2 days after irradiation, with crypt hypoplasia, and at 5 days after irradiation when there was reactive crypt hyperplasia. However reconstitution of donors with normal spleen cells immediately after irradiation restored their capacity to generate a tolerogenic form of the antigen. Immunoreactive OVA was detected by ELISA in both tolerizing and non-tolerizing sera, and the immunological properties of these sera were not related to serum levels of OVA after feeding. The results suggest that lymphoid cells may be involved in the phenomenon of antigen processing.

  13. Reduced Cost of Reactive Power in Doubly Fed Induction Generator Wind Turbine System with Optimized Grid Filter

    DEFF Research Database (Denmark)

    Zhou, Dao; Blaabjerg, Frede; Franke, Toke

    2014-01-01

    The modern grid requirement has caused that the wind power system behaves more like conventional rotating generators and it is able to support certain amount of the reactive power. For a typical doubly-fed induction generator wind turbine system, the reactive power can be supported either through...... for the generator and the wind power converter in terms of the reactive power done by the rotor-side converter or the grid-side converter with various grid filters. Afterwards, the annual energy loss is also estimated based on yearly wind profile. Finally, experimental results of the loss distribution are performed...... the rotor-side converter or the grid-side converter. This paper firstly compares the current ripples and supportive reactive power ranges between the conventional L and optimized LCL filter, if the reactive power is injected from the grid-side converter. Then, the loss distribution is evaluated both...

  14. Reduced Cost of Reactive Power in Doubly Fed Induction Generator Wind Turbine System With Optimized Grid Filter

    DEFF Research Database (Denmark)

    Zhou, Dao; Blaabjerg, Frede; Franke, Toke

    2015-01-01

    The modern grid requirement has caused that the wind power system behaves more like conventional rotating generators, and it is able to support certain amount of the reactive power. For a typical doubly fed induction generator (DFIG) wind turbine system, the reactive power can be supported either...... for the generator and the wind power converter in terms of the reactive power done by the rotor-side converter or the grid-side converter with various grid filters. Afterward, the annual energy loss is also estimated based on yearly wind profile. Finally, experimental results of the loss distribution are performed...... through the rotor-side converter or the grid-side converter. This paper first compares the current ripples and supportive reactive power ranges between the conventional L and optimized LCL filter, if the reactive power is injected from the grid-side converter. Then, the loss distribution is evaluated both...

  15. Optimizing Winter Wheat Resilience to Climate Change in Rain Fed Crop Systems of Turkey and Iran

    Directory of Open Access Journals (Sweden)

    Marta S. Lopes

    2018-05-01

    Full Text Available Erratic weather patterns associated with increased temperatures and decreasing rainfall pose unique challenges for wheat breeders playing a key part in the fight to ensure global food security. Within rain fed winter wheat areas of Turkey and Iran, unusual weather patterns may prevent attaining maximum potential increases in winter wheat genetic gains. This is primarily related to the fact that the yield ranking of tested genotypes may change from one year to the next. Changing weather patterns may interfere with the decisions breeders make about the ideotype(s they should aim for during selection. To inform breeding decisions, this study aimed to optimize major traits by modeling different combinations of environments (locations and years and by defining a probabilistic range of trait variations [phenology and plant height (PH] that maximized grain yields (GYs; one wheat line with optimal heading and height is suggested for use as a testing line to aid selection calibration decisions. Research revealed that optimal phenology was highly related to the temperature and to rainfall at which winter wheat genotypes were exposed around heading time (20 days before and after heading. Specifically, later winter wheat genotypes were exposed to higher temperatures both before and after heading, increased rainfall at the vegetative stage, and reduced rainfall during grain filling compared to early genotypes. These variations in exposure to weather conditions resulted in shorter grain filling duration and lower GYs in long-duration genotypes. This research tested if diversity within species may increase resilience to erratic weather patterns. For the study, calculated production of a selection of five high yielding genotypes (if grown in five plots was tested against monoculture (if only a single genotype grown in the same area and revealed that a set of diverse genotypes with different phenologies and PHs was not beneficial. New strategies of progeny

  16. Nutrient retention capabilities of Nile tilapia ( Oreochromis niloticus) fed bio-regenerative life support system (BLSS) waste residues

    Science.gov (United States)

    Gonzales, John M.; Brown, Paul B.

    Nile tilapia were evaluated as a bio-regenerative sub-process for reducing solid waste potentially encountered in bio-regenerative life support systems. Ten juvenile Nile tilapia (mean weight = 2.05 g) were stocked into triplicate aquaria and fed one of seven experimental diets consisting of vegetable, bacterial, or food waste for a period of seven weeks. Weight gain (g), specific growth rate (mg/d), and daily consumption (g) was significantly higher ( p diet (37.99 and 68.54, respectively) followed by fish fed the wheat bran/wheat germ diet (23.19 and 63.67, respectively). Nitrogen, sulfur, and crude protein retention was significantly higher ( p diet (23.68, 21.89, and 23.68, respectively). A general loss of minerals was observed among all groups. Strong associations were observed between crude lipid retention and sulfur retention ( r2 = 0.94), crude lipid retention and carbon retention ( r2 = 0.92), WG and fiber content of dietary treatments ( r2 = 0.92), WG and carbon retention and ( r2 = 0.88), WG and lysine content of waste residues ( r2 = 0.86), crude protein retention and carbon retention ( r2 = 0.84), sulfur retention and crude protein retention ( r2 = 0.84), and total sulfur amino acid (TSAA) content of residues and WG ( r2 = 0.81). Weaker associations existed between WG and crude lipid retention ( r2 = 0.77), crude fiber content and carbon retention ( r2 = 0.76), and WG and methionine content of waste residues ( r2 = 0.75). Additional research is needed to improve the nutritional quality of fibrous residues as a means to improve tilapia's ability to utilize these residues as a food source in bio-regenerative support systems.

  17. Design of a Solar Motor Drive System Fed by a Direct-Connected Photovoltaic Array

    Directory of Open Access Journals (Sweden)

    AYDOGMUS, O.

    2012-08-01

    Full Text Available A solar motor pump drive system is modeled and simulated. The proposed drive system does not require any kind of energy storage system and dc-dc converter. The system is connected directly to a photovoltaic (PV array. Thus, a low cost solar system can be achieved. A vector controlled Permanent Magnet Synchronous Motor (PMSM is used as a solar motor to increase the efficiency of system. The motor is designed for a low rated voltage level about 24V. The hill climbing MPPT method is used for balanced the motor power and PV power to obtain a high efficiency. The results are performed by using MATLAB/SimPowerSystem blocks. In addition, the PV array is modeled to allow for the possibility of running as on-line adjustable in simulation environment without using lookup table. The performances of motor, MPPT and drive system are analyzed in different conditions as temperature and irradiation of PV array.

  18. A bioelectrochemical approach to characterize extracellular electron transfer by Synechocystis sp. PCC6803.

    Directory of Open Access Journals (Sweden)

    Angelo Cereda

    Full Text Available Biophotovoltaic devices employ photosynthetic organisms at the anode of a microbial fuel cell to generate electrical power. Although a range of cyanobacteria and algae have been shown to generate photocurrent in devices of a multitude of architectures, mechanistic understanding of extracellular electron transfer by phototrophs remains minimal. Here we describe a mediatorless bioelectrochemical device to measure the electrogenic output of a planktonically grown cyanobacterium, Synechocystis sp. PCC6803. Light dependent production of current is measured, and its magnitude is shown to scale with microbial cell concentration and light intensity. Bioelectrochemical characterization of a Synechocystis mutant lacking Photosystem II demonstrates conclusively that production of the majority of photocurrent requires a functional water splitting aparatus and electrons are likely ultimately derived from water. This shows the potential of the device to rapidly and quantitatively characterize photocurrent production by genetically modified strains, an approach that can be used in future studies to delineate the mechanisms of cyanobacterial extracellular electron transport.

  19. Doubly Fed Induction Generator System Resonance Active Damping through Stator Virtual Impedance

    DEFF Research Database (Denmark)

    Song, Yipeng; Wang, Xiongfei; Blaabjerg, Frede

    2017-01-01

    (positive capacitor or negative inductor) into the stator branch through stator current feedforward control. The effectiveness of the DFIG system active damping control is verified by a 7.5 kW experimental down-scaled DFIG system, and simulation results of a commercial 2 MW DFIG system is provided as well....... converters/loads. This paper analyzes and explains first the HFR phenomenon between the DFIG system and a parallel compensated weak network (series RL + shunt C). Then on the basis of the DFIG system impedance modeling, an active damping control strategy is introduced by inserting a virtual impedance...... Frequency Resonance (HFR) due to the impedance interaction between the DFIG system and the weak grid network whose impedance is comparative large. Thus, it is important to implement an active damping for the HFR in order to ensure a safe and reliable operation of both the DFIG system and the grid connected...

  20. Farmers’ knowledge, use and preferences of parasitic weed management strategies in rain-fed rice production systems

    NARCIS (Netherlands)

    Tippe, Dennis E.; Rodenburg, Jonne; Schut, Marc; Ast, van Aad; Kayeke, Juma; Bastiaans, Lammert

    2017-01-01

    Rain-fed rice production in sub-Saharan Africa is often hampered by parasitic weeds. This study assessed farmers’ awareness, use, preference and adoption criteria of parasitic weed management practices in rain-fed rice production environments in Tanzania. Surveys and workshops were organized in

  1. The Concept of Autonomous Power Supply System Fed with Renewable Energy Sources

    Directory of Open Access Journals (Sweden)

    Waldemar Fedak

    2017-12-01

    Full Text Available Sustainable economic development requires the use of renewable energy sources in a rational and thoughtful way. In Polish conditions the use of several types of renewable energy sources on a single setup is a new issue. In particular, hybrid devices in conjunction with intelligent energy systems, such as lighting systems are generally not used. Therefore, the Polish energy production still relies on the burning of coal. Despite their advantages, renewable energy sources are characterized by seasonality and considerable instability. Access to renewable energy varies daily and seasonally, hence activities promoting the use of autonomous, hybrid power systems must be intensified. The presented research aims at the development of the Autonomous Power Supply (APS system based on the so-called energy mix. Such a system works in an isolated arrangement and serves to reliably supply electricity from renewable sources for small residential or public utility devices in an urban area. Systems with up to 3 kW power consist of modules, whose modular design allows the combination of various power configurations and types of renewable energy used. The basic system consists of a primary power source, additional power source, emergency power source, energy storage device, weather station and controller. The energy mix depends on the geographical location of the system. The emergency source can be implemented as an on-grid connector or fuel power generator with the participation of 100% until the primary or accessory power source failure is removed. The energy storage system consists of batteries or supercapacitors. The proposed system can be combined to create a local network that automatically responds to energy shortages in various network nodes by adjusting the supply of electricity within the network depending on its needs. For Poland realistic solutions in this article are the new and modern answer to these requirements.

  2. Whole-milk feeding duration, calf growth, and profitability of group-fed calves in an organic production system.

    Science.gov (United States)

    Bjorklund, E A; Heins, B J; Chester-Jones, H

    2013-01-01

    The objective of this study was to evaluate the effect of early-life feeding duration on growth and economics of group-fed organic dairy calves. Heifer calves born during the spring of 2011 (n = 67) and the spring of 2012 (n = 57) were used to evaluate the effect of weaning age, growth, and profitability of group-fed calves fed once per day in an organic dairy production system. Calves were assigned to replicate feeding groups of 10 in super hutches by birth order, and were born at the University of Minnesota West Central Research and Outreach Center, Morris organic dairy. Breed groups were Holsteins (n = 15) selected for high production, Holsteins (n = 23) maintained at 1964 breed-average level, crossbreds (n = 54) including combinations of Holstein, Montbéliarde, and Swedish Red, and crossbreds (n = 32) including combinations of Holstein, New Zealand Friesian, Jersey, and Swedish Red. Groups of calves were weaned at 30 (EW, early weaning), 60 (MW, mid weaning), or 90 (LW, late weaning) d of age, and groups were fed 1.5% of birth weight of 13% total solids organic whole milk once daily and weaned when the group of 10 calves consumed an average of 0.91 kg of organic calf starter per calf per day for 4 consecutive days. Body measurements were recorded at birth, weekly during the preweaning period, at weaning, and monthly thereafter. Profitability was estimated as a function of the total cost for organic milk and organic calf starter for weaning groups to weaning and to the first 90 d of age. Preweaning group performance was weaning age, EW: 47.6d, MW: 64.5d, LW: 93.7d; weaning weight, EW: 61.8 kg, MW: 79.2 kg, LW: 108.1 kg; and gain per day, EW: 0.51 kg/d, MW: 0.63 kg/d, LW: 0.75 kg/d. Body weight (BW) did not differ among weaning groups at 90 d of age; however, MW calves had lower 120-d BW than did LW calves. The EW calves did not differ from either MW or LW calves for 120-d BW. Total feed costs to weaning for groups were $1,092.97 for EW calves, $1,871.24 for MW

  3. Development and Optimization of a Tridyne Pressurization System for Pressure Fed Launch Vehicles

    National Research Council Canada - National Science Library

    Chakroborty, Shyama; Wollen, Mark; Malany, Lee

    2006-01-01

    Over the recent years, Microcosm has been pursuing the development of a Tridyne-based pressurization system and its implementation in the Scorpius family of launch vehicles to obtain substantial gain in payload to orbit...

  4. Simulation study of a PEM fuel cell system fed by hydrogen produced by partial oxidation

    Energy Technology Data Exchange (ETDEWEB)

    Ozdogan, S [Marmara University, Faculty of Engineering, Istanbul (Turkey); Ersoz, A; Olgun, H [TUBITAK Marmara Research Center, Energy Systems and Environmental Research Institute, Kocaeli (Turkey)

    2003-09-01

    Within the frame of sustainable development, efficient and clean, if possible zero emission energy production technologies are of utmost importance in various sectors such as utilities, industry, households and transportation. Low-temperature fuel cell systems are suitable for powering transportation systems such as automobiles and trucks in an efficient and low-emitting manner. Proton exchange membrane (PEM) fuel cell systems constitute the most promising low temperature fuel cell option being developed globally. PEM fuel cells generate electric power from air and hydrogen or from a hydrogen rich gas via electrochemical reactions. Water and waste heat are the only by-products of PEM fuel cells. There is great interest in converting current hydrocarbon based common transportation fuels such as gasoline and diesel into hydrogen rich gases acceptable by PEM fuel cells. Hydrogen rich gases can be produced from conventional transportation fuels via various reforming technologies. Steam reforming, partial oxidation and auto-thermal reforming are the three major reforming technologies. In this paper, we discuss the results of a simulation study for a PEM fuel cell with partial oxidation. The Aspen HYSYS 3.1 code has been used for simulation purposes. Two liquid hydrocarbon fuels have been selected to investigate the effect of average molecular weights of hydrocarbons, on the fuel processing efficiency. The overall system efficiency depends on the fuel preparation and fuel cell efficiencies as well as on the heat integration within the system. It is desired to investigate the overall system efficiencies for net electrical power production at 100 kW considering bigger scale transport applications. Results indicate that fuel properties, fuel preparation system operating parameters and PEM fuel cell polarization curve characteristics all affect the overall system efficiency. (authors)

  5. Boost Converter Fed High Performance BLDC Drive for Solar PV Array Powered Air Cooling System

    Directory of Open Access Journals (Sweden)

    Shobha Rani Depuru

    2017-01-01

    Full Text Available This paper proposes the utilization of a DC-DC boost converter as a mediator between a Solar Photovoltaic (SPV array and the Voltage Source Inverters (VSI in an SPV array powered air cooling system to attain maximum efficiency. The boost converter, over the various common DC-DC converters, offers many advantages in SPV based applications. Further, two Brushless DC (BLDC motors are employed in the proposed air cooling system: one to run the centrifugal water pump and the other to run a fan-blower. Employing a BLDC motor is found to be the best option because of its top efficiency, supreme reliability and better performance over a wide range of speeds. The air cooling system is developed and simulated using the MATLAB/Simulink environment considering the steady state variation in the solar irradiance. Further, the efficiency of BLDC drive system is compared with a conventional Permanent Magnet DC (PMDC motor drive system and from the simulated results it is found that the proposed system performs better.

  6. Doubly Fed Induction Generator Wind Turbine Systems Subject to Recurring Symmetrical Grid Faults

    DEFF Research Database (Denmark)

    Chen, Wenjie; Blaabjerg, Frede; Zhu, Nan

    2016-01-01

    New grid codes demand the wind turbine systems to ride through recurring grid faults. In this paper, the performance of the doubly Ffed induction generator (DFIG) wind turbine system under recurring symmetrical grid faults is analyzed. The mathematical model of the DFIG under recurring symmetrical...... grid faults is established. The analysis is based on the DFIG wind turbine system with the typical low-voltage ride-through strategy-with rotor-side crowbar. The stator natural flux produced by the voltage recovery after the first grid fault may be superposed on the stator natural flux produced...... by the second grid fault, so that the transient rotor and stator current and torque fluctuations under the second grid fault may be influenced by the characteristic of the first grid fault, including the voltage dips level and the grid fault angle, as well as the duration between two faults. The mathematical...

  7. Modeling and analysis of doubly fed induction generator wind energy systems

    CERN Document Server

    Fan, Lingling

    2015-01-01

    Wind Energy Systems: Modeling, Analysis and Control with DFIG provides key information on machine/converter modelling strategies based on space vectors, complex vector, and further frequency-domain variables. It includes applications that focus on wind energy grid integration, with analysis and control explanations with examples. For those working in the field of wind energy integration examining the potential risk of stability is key, this edition looks at how wind energy is modelled, what kind of control systems are adopted, how it interacts with the grid, as well as suitable study

  8. Small-Signal Stability Analysis of Inverter-Fed Power Systems Using Component Connection Method

    DEFF Research Database (Denmark)

    Wang, Yanbo; Wang, Xiongfei; Blaabjerg, Frede

    2018-01-01

    The small time constants of power electronics devices lead to dynamic couplings with the electromagnetic transients of power networks, and thus complicate the modeling and stability analysis of power-electronics-based power systems. This paper presents a computationally-efficient approach to asse...

  9. Strategies for improving water use efficiency of livestock production in rain-fed systems.

    Science.gov (United States)

    Kebebe, E G; Oosting, S J; Haileslassie, A; Duncan, A J; de Boer, I J M

    2015-05-01

    Livestock production is a major consumer of fresh water, and the influence of livestock production on global fresh water resources is increasing because of the growing demand for livestock products. Increasing water use efficiency of livestock production, therefore, can contribute to the overall water use efficiency of agriculture. Previous studies have reported significant variation in livestock water productivity (LWP) within and among farming systems. Underlying causes of this variation in LWP require further investigation. The objective of this paper was to identify the factors that explain the variation in LWP within and among farming systems in Ethiopia. We quantified LWP for various farms in mixed-crop livestock systems and explored the effect of household demographic characteristics and farm assets on LWP using ANOVA and multilevel mixed-effect linear regression. We focused on water used to cultivate feeds on privately owned agricultural lands. There was a difference in LWP among farming systems and wealth categories. Better-off households followed by medium households had the highest LWP, whereas poor households had the lowest LWP. The variation in LWP among wealth categories could be explained by the differences in the ownership of livestock and availability of family labor. Regression results showed that the age of the household head, the size of the livestock holding and availability of family labor affected LWP positively. The results suggest that water use efficiency could be improved by alleviating resource constraints such as access to farm labor and livestock assets, oxen in particular.

  10. Mechanistic Models for Process Development and Optimization of Fed-batch Fermentation Systems

    DEFF Research Database (Denmark)

    Mears, Lisa; Stocks, Stuart M.; Albæk, Mads O.

    2016-01-01

    This work discusses the application of mechanistic models to pilot scale filamentous fungal fermentation systems operated at Novozymes A/S. For on-line applications, a state estimator model is developed based on a stoichiometric balance in order to predict the biomass and product concentration....... This is based on on-line gas measurements and ammonia addition flow rate measurements. Additionally, a mechanistic model is applied offline as a tool for batch planning, based on definition of the process back pressure, aeration rate and stirrer speed. This allows the batch starting fill to be planned, taking...... into account the oxygen transfer conditions, as well as the evaporation rates of the system. Mechanistic models are valuable tools which are applicable for both process development and optimization. The state estimator described will be a valuable tool for future work as part of control strategy development...

  11. Stellar systems fed by outside stars: the evolution of model galactic nuclei

    International Nuclear Information System (INIS)

    Dokuchaev, V.I.; Ozernoi, L.M.

    1985-01-01

    Through relaxation mechanisms, a dense central core surrounded by an extended, rarefied stellar system in a nonisothermal galactic nuclear region can be kept supplied with energy and mass conveyed by incoming stars. These factors may significantly influence the secular evolution of the core, competing with the conventional star-evaporation process. Under certain circumstances the outside environment will in fact dominate the core evolution, causing not collapse but expansion

  12. High Efficiency Power Converter for a Doubly-fed SOEC/SOFC System

    DEFF Research Database (Denmark)

    Tomas Manez, Kevin; Anthon, Alexander; Zhang, Zhe

    2016-01-01

    Regenerative fuel cells (RFC) have become an attractive technology for energy storage systems due to their high energy density and lower end-of-life disposal concerns. However, high efficiency design of power conditioning unit (PCU) for RFC becomes challenging due to their asymmetrical currentpow...... operating range of the RFC as well as the utilization of the same control strategy design for the two RFC operating modes....

  13. Off-gas system data summary for the ninth run of the large slurry fed melter

    International Nuclear Information System (INIS)

    Colven, W.P.

    1983-01-01

    The ninth melter campaign successfully demonstrated extended operation of both melter and off-gas systems. Two critical problem areas associated with the handling of melter off-gases were resolved leading to firm definition of the DWPF Off-Gas Treatment System. These two concerns, wet scrubber decontamination efficiency and the reduction of solids deposition at the off-gas line entrance, were the primary focus of off-gas system studies during the 63-day run (LSFM-9). The Hydro-Sonic Scrubber was confirmed to be the superior candidate for wet scrubbing by outperforming all other scrubbers tested at the Equipment Test Facility (ETF). The two stage, steam-driven scrubber achieved consistent decontamination factors for cesium exceeding the required DWPF flowsheet DF of 50. As a result, the device was selected as the reference wet scrubber for the DWPF. The Off-Gas Film Cooling device continued to show promising results for reducing three accumulation of solid deposits at the entrance to the off-gas line. In addition, a rotating wire brush cleaning device provided easy and efficient removal of deposits which had accumulated. The combination of the two has adequately resolved the deposit accumulation problem and both devices have been incorporated in the DWPF design

  14. Fungi from a Groundwater-Fed Drinking Water Supply System in Brazil.

    Science.gov (United States)

    Oliveira, Helena M B; Santos, Cledir; Paterson, R Russell M; Gusmão, Norma B; Lima, Nelson

    2016-03-09

    Filamentous fungi in drinking water distribution systems are known to (a) block water pipes; (b) cause organoleptic biodeterioration; (c) act as pathogens or allergens and (d) cause mycotoxin contamination. Yeasts might also cause problems. This study describes the occurrence of several fungal species in a water distribution system supplied by groundwater in Recife-Pernambuco, Brazil. Water samples were collected from four sampling sites from which fungi were recovered by membrane filtration. The numbers in all sampling sites ranged from 5 to 207 colony forming units (CFU)/100 mL with a mean value of 53 CFU/100 mL. In total, 859 isolates were identified morphologically, with Aspergillus and Penicillium the most representative genera (37% and 25% respectively), followed by Trichoderma and Fusarium (9% each), Curvularia (5%) and finally the species Pestalotiopsis karstenii (2%). Ramichloridium and Leptodontium were isolated and are black yeasts, a group that include emergent pathogens. The drinking water system in Recife may play a role in fungal dissemination, including opportunistic pathogens.

  15. Fungi from a Groundwater-Fed Drinking Water Supply System in Brazil

    Directory of Open Access Journals (Sweden)

    Helena M.B. Oliveira

    2016-03-01

    Full Text Available Filamentous fungi in drinking water distribution systems are known to (a block water pipes; (b cause organoleptic biodeterioration; (c act as pathogens or allergens and (d cause mycotoxin contamination. Yeasts might also cause problems. This study describes the occurrence of several fungal species in a water distribution system supplied by groundwater in Recife—Pernambuco, Brazil. Water samples were collected from four sampling sites from which fungi were recovered by membrane filtration. The numbers in all sampling sites ranged from 5 to 207 colony forming units (CFU/100 mL with a mean value of 53 CFU/100 mL. In total, 859 isolates were identified morphologically, with Aspergillus and Penicillium the most representative genera (37% and 25% respectively, followed by Trichoderma and Fusarium (9% each, Curvularia (5% and finally the species Pestalotiopsis karstenii (2%. Ramichloridium and Leptodontium were isolated and are black yeasts, a group that include emergent pathogens. The drinking water system in Recife may play a role in fungal dissemination, including opportunistic pathogens.

  16. Cirlularly Polarized Proximity- Fed Microstrip Array Antenna for LAPAN TUBSAT Micro Satellite System

    Directory of Open Access Journals (Sweden)

    Endra Wijaya

    2013-11-01

    Full Text Available The design microstrip of array antenna circular polarization characteristic developed for support LAPAN TUBSAT micro satellite system. The antenna on the micro satellite systems transmit data to ground stations operating at S band frequencies.The antenna is designed for impedance matching at frequencies of 2:25 GHz.The four elements of the square patch antenna array composed using linear methods, where the design of the transmission lines used by federal corporate structure model network consisting of three elements of the quarter wave transformer of a power divider. The feeding techniques for antenna designed using proximity coupling method, which for the type of substrate material used is similar. Circularly polarized antenna characteristics are influenced by the truncated corner pieces on the patch. To design the overall antenna used simulated method of moments in microwave office software applications. The results of measurements and simulations obtained antenna parameters, such as: bandwidth of return loss under 10 dB is 200 MHz (shifted 35%, bandwidth of axial ratio under 3dB is 1.7% and maximum gain directivity is 9 dB. Overall results obtained antenna parameters to meet the specifications of LAPAN TUBSAT micro satellite system.

  17. Fillet quality and processing attributes of postsmolt Atlantic salmon, Salmo salar, fed a fishmeal-free diet and a fishmeal-based diet in recirculation aquaculture systems

    Science.gov (United States)

    Many studies have evaluated the adequacy of alternate ingredient diets for Atlantic salmon, Salmo salar, mainly with focus on fish performance and health; however, comprehensive analysis of fillet quality is lacking, particularly for salmon fed these diets in recirculation aquaculture systems (RAS)....

  18. New control strategy of stand-alone brushless doubly-fed induction generator for supplying unbalanced loads in ship shaft power generation system

    DEFF Research Database (Denmark)

    Liu, Yi; Xu, Wei; Xiong, Fei

    2017-01-01

    The ship shaft power generation system based on a stand-alone brushless doubly-fed induction generator (BDFIG) have demonstrated excellent saving-energy performance. This paper presents a new control scheme of the stand-alone BDFIG for supplying unbalanced loads in the ship shaft power generation...

  19. LFCM [liquid-fed eramic melter] emission and off-gas system performance for feed component cesium

    International Nuclear Information System (INIS)

    Goles, R.W.; Andersen, C.M.

    1986-09-01

    Except for volatile off-gas effluents, overall adequacy of the liquid-fed ceramic melter (LFCM) system depends most upon its effectiveness in dealing with cesium. However, the mechanism responsible for melter cesium losses has proved insensitive to many LFCM operating and processing conditions. As a result, variations in inleakage, plenum temperature, feeding rate and waste loading do not significantly influence melter cesium performance. Feed composition, specifically halogen content, is the only processing variable that has had a significant effect. Due to the submicron nature of LFCM-generated aerosols, melter disengagement design features are not expected to be particularly effective in reducing cesium emission rates. For the same reason, the cesium performance of conventional quench scrubbers is quite low, being dependent only upon the magnitude of melter entrainment losses. Although a deep bed washable filter has been effective in removing submicron aerosols from the process exhaust, high performance has only been achieved under dry operating conditions. The melter's idling state does not appear to place additional demands upon the off-gas treatment system

  20. Study of LCL filter performance for inverter fed grid connected system

    Science.gov (United States)

    Thamizh Thentral, T. M.; Geetha, A.; Subramani, C.

    2018-04-01

    The abandoned use of power electronic converters in the application of grid connected system paves a way for critical injected harmonics. Hence the use of filter becomes a significant play among the present scenario. Higher order passive filter is mostly preferred in this application because of its reduced cost and size. This paper focuses on the design of LCL filter for the reduction of injected harmonics. The reason behind choosing LCL filter is inductor sizing and good ripple component attenuation over the other conventional filters. This work is simulated in MATLAB platform and the results are prominent to the objectives mentioned above. Also, the simulation results are verified with the implemented hardware model.

  1. Hungry in hospital, well-fed in prison? A comparative analysis of food service systems.

    Science.gov (United States)

    Johns, Nick; Edwards, John S A; Hartwell, Heather J

    2013-09-01

    Meals served in prisons and hospitals are produced in similar ways and have similar characteristics, yet hospital patients are often at risk of being undernourished, while prisoners typically are not. This article examines field notes collected during nutritional studies of prison and hospital food service, which confirmed the difference in nutrient intake claimed by other authors. A comparison of food service processes and systems showed that the production of meals and the quality leaving the kitchen was similar in both types of institution. However, the delivery and service system was found to be much less coherent in hospital than in prison. Transport and service of hospital food were subject to delays and disruptions from a number of sources, including poor communication and the demands of medical professionals. These meant that meals reached hospital patients in a poorer, less appetising condition than those received by prisoners. The findings are discussed in the light of previous work and in terms of hospital food service practice. Crown Copyright © 2013. Published by Elsevier Ltd. All rights reserved.

  2. Influence of housing system, grain type, and particle size on Salmonella colonization and shedding of broilers fed triticale or corn-soybean meal diets.

    Science.gov (United States)

    Santos, F B O; Sheldon, B W; Santos, A A; Ferket, P R

    2008-03-01

    Salmonella colonization in poultry may be influenced by grain type and particle size. Broilers reared either in nonlitter cage-based housing or in a conventionally floored litter house from 0 to 42 d were assigned to 1 of 4 dietary treatments: 1) ground corn-soybean meal (C, 560 microm), 2) coarsely ground corn-soybean meal (CC, >1,700 microm), 3) ground triticale-soybean meal (T, 560 microm), or 4) whole triticale-soybean meal (WT). A 4-strain cocktail of Salmonella enterica was orally gavaged into each chick at placement. Growth performance, cecal and fecal Salmonella populations, gizzard and proventriculus pH, intestinal size, jejunum histomorphometry, and carcass yields were measured. Broilers responded differently to the dietary treatments according to the housing system used. At 42 d, birds reared on litter and fed ground grain had greater BW than those fed coarse grain (2.87 vs. 2.71 kg), whereas cage-reared broilers fed ground triticale were heavier than those fed corn (2.75 vs. 2.64 kg). Broilers raised on litter had a better feed conversion ratio than those raised in cages (1.71 vs. 1.81 g/g). Independent of the housing system, relative eviscerated carcass weights of birds fed T and C were heavier than those of CC- and WT-fed broilers (762 vs. 752 g/kg). Generally, the jejunum villus area and mucosal depth were larger, whereas the small intestine was lighter and shorter in broilers raised on litter. Relative gizzard weights of broilers raised on litter and fed the coarser diets were heavier than those of broilers reared in cages and fed finely ground diets. Feeding whole or coarsely ground grains decreased cecal Salmonella populations in 42-d-old broilers (3.8, 3.9, 4.4, and 4.4 log most probable number/g for CC, WT, C, and T, respectively). Additionally, 42-d-old broilers reared on litter had lower cecal Salmonella populations than those in cages (3.8 vs. 4.4 log most probable number/g). In conclusion, as a feed ingredient, triticale is a good

  3. Hydrological behavior of a Vertisol under different soil management systems in a rain-fed olive orchard

    Science.gov (United States)

    Cabezas, Jose Manuel; Gómez, Jose Alfonso; Auxiliadora Soriano, María

    2016-04-01

    Soil water availability is a major subject in Mediterranean agricultural systems, mainly due to the limited and highly variable annual rainfall, high evaporative demand, and soil hydrological characteristics. The recent expansion of olive cultivation in the rolling-plains of the Guadalquivir valley, due to the higher profitability of new intensive olive orchards, expanded the presence of olive orchards on Vertisols, soils traditionally used for annual rain-fed crops. These soils have a high content of smectitic clays, which give them a high water storage capacity, and are characterized by vertical and deep shrinkage cracks in the dry season, associated to low soil moisture. Farmers make several tillage passes in these olive groves during the summer, in order to cover the cracks and thus reduce soil water loss by evaporation, which will impact especially in rain-fed in the next olive yield. This tillage practice involves removal of plant residues from the soil surface, as well as burying seeds produced by the plants, so this will remain bared at the beginning of the rainy season, when in the Mediterranean climate is frequent occurrence of high-intensity rainfall, which are ideal conditions for soil loss by water erosion, one of the most serious problems for the sustainability of olive cultivation in Andalusia. Although there are some studies showing that water loss by evaporation from deep horizons of a vertic soil might be elevated (eg. Ritchie and Adams, 1974), the presence of plant residues on the soil surface drastically reduced soil water loss (eg Adams et al., 1969). Thus the aim of this study was to assess of soil moisture dynamics in a rain-fed olive orchard growing on a Vertisol under different soil management practices, in Andalusia (southern Spain). Four different soil management treatments were applied, which combined a cover crop (Bromus rubens L.) or bare soil throughout the year by applying herbicides, with tillage in summer to cover the cracks or non

  4. Depletion of norepinephrine of the central nervous system Down-regulates the blood glucose level in d-glucose-fed and restraint stress models.

    Science.gov (United States)

    Park, Soo-Hyun; Kim, Sung-Su; Lee, Jae-Ryeong; Sharma, Naveen; Suh, Hong-Won

    2016-05-04

    DSP-4[N-(2-chloroethyl)-N-ethyl-2-bromobenzylamine hydrochloride] is a neurotoxin that depletes norepinephrine. The catecholaminergic system has been implicated in the regulation of blood glucose level. In the present study, the effect of DSP-4 administered intracerebroventricularly (i.c.v.) or intrathecally (i.t.) on blood glucose level was examined in d-glucose-fed and restraint stress mice models. Mice were pretreated once i.c.v. or i.t. with DSP-4 (10-40μg) for 3days, and d-glucose (2g/kg) was fed orally. Blood glucose level was measured 0 (prior to glucose feeding or restraint stress), 30, 60, and 120min after d-glucose feeding or restraint stress. The i.c.v. or i.t. pretreatment with DSP-4 attenuated blood glucose level in the d-glucose-fed model. Plasma corticosterone level was downregulated in the d-glucose-fed model, whereas plasma insulin level increased in the d-glucose-fed group. The i.c.v. or i.t. pretreatment with DSP-4 reversed the downregulation of plasma corticosterone induced by feeding d-glucose. In addition, the d-glucose-induced increase in plasma insulin was attenuated by the DSP-4 pretreatment. Furthermore, i.c.v. or i.t. pretreatment with DSP-4 reduced restraint stress-induced increases in blood glucose levels. Restraint stress increased plasma corticosterone and insulin levels. The i.c.v. pretreatment with DSP-4 attenuated restraint stress-induced plasma corticosterone and insulin levels. Our results suggest that depleting norepinephrine at the supraspinal and spinal levels appears to be responsible for downregulating blood glucose levels in both d-glucose-fed and restraint stress models. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

  5. Comparison of particle-exposure triggered pulmonary and systemic inflammation in mice fed with three different diets.

    Science.gov (United States)

    Götz, Alexander A; Rozman, Jan; Rödel, Heiko G; Fuchs, Helmut; Gailus-Durner, Valérie; Hrabě de Angelis, Martin; Klingenspor, Martin; Stoeger, Tobias

    2011-09-27

    Obesity can be linked to disease risks such as diabetes and cardiovascular disorders, but recently, the adipose tissue (AT) macrophage also emerges as actively participating in inflammation and immune function, producing pro- and anti-inflammatory factors. Connections between the AT and chronic lung diseases, like emphysema and asthma and a protective role of adipocyte-derived proteins against acute lung injury were suggested.In this study we addressed the question, whether a diet challenge increases the inflammatory response in the alveolar and the blood compartment in response to carbon nanoparticles (CNP), as a surrogate for ambient/urban particulate air pollutants. Mice were fed a high caloric carbohydrate-rich (CA) or a fat-rich (HF) diet for six weeks and were compared to mice kept on a purified low fat (LF) diet, respectively. Bronchoalveolar lavage (BAL) and blood samples were taken 24 h after intratracheal CNP instillation and checked for cellular and molecular markers of inflammation. The high caloric diets resulted in distinct effects when compared with LF mice, respectively: CA resulted in increased body and fat mass without affecting blood cellular immunity. Conversely, HF activated the blood system, increasing lymphocyte and neutrophil counts, and resulted in slightly increased body fat content. In contrast to higher pro-inflammatory BAL Leptin in CA and HF mice, on a cellular level, both diets did not lead to an increased pro-inflammatory basal status in the alveolar compartment per se, nor did result in differences in the particle-triggered response. However both diets resulted in a disturbance of the alveolar capillary barrier as indicated by enhanced BAL protein and lactate-dehydrogenase concentrations. Systemically, reduced serum Adiponectin in HF mice might be related to the observed white blood cell increase. The increase in BAL pro-inflammatory factors in high caloric groups and reductions in serum concentrations of anti-inflammatory factors

  6. Comparison of particle-exposure triggered pulmonary and systemic inflammation in mice fed with three different diets

    Directory of Open Access Journals (Sweden)

    Hrabě de Angelis Martin

    2011-09-01

    Full Text Available Abstract Background Obesity can be linked to disease risks such as diabetes and cardiovascular disorders, but recently, the adipose tissue (AT macrophage also emerges as actively participating in inflammation and immune function, producing pro- and anti-inflammatory factors. Connections between the AT and chronic lung diseases, like emphysema and asthma and a protective role of adipocyte-derived proteins against acute lung injury were suggested. In this study we addressed the question, whether a diet challenge increases the inflammatory response in the alveolar and the blood compartment in response to carbon nanoparticles (CNP, as a surrogate for ambient/urban particulate air pollutants. Methods Mice were fed a high caloric carbohydrate-rich (CA or a fat-rich (HF diet for six weeks and were compared to mice kept on a purified low fat (LF diet, respectively. Bronchoalveolar lavage (BAL and blood samples were taken 24 h after intratracheal CNP instillation and checked for cellular and molecular markers of inflammation. Results and discussion The high caloric diets resulted in distinct effects when compared with LF mice, respectively: CA resulted in increased body and fat mass without affecting blood cellular immunity. Conversely, HF activated the blood system, increasing lymphocyte and neutrophil counts, and resulted in slightly increased body fat content. In contrast to higher pro-inflammatory BAL Leptin in CA and HF mice, on a cellular level, both diets did not lead to an increased pro-inflammatory basal status in the alveolar compartment per se, nor did result in differences in the particle-triggered response. However both diets resulted in a disturbance of the alveolar capillary barrier as indicated by enhanced BAL protein and lactate-dehydrogenase concentrations. Systemically, reduced serum Adiponectin in HF mice might be related to the observed white blood cell increase. Conclusion The increase in BAL pro-inflammatory factors in high caloric

  7. A class of flux observers for doubly-fed induction generators used in small power wind generation systems

    DEFF Research Database (Denmark)

    Lascu, C.; Boldea, I.; Blaabjerg, Frede

    2013-01-01

    This paper investigates a family of stator and rotor flux observers for sensorless operation of doubly-fed induction generators (DFIG). Four stator flux observer topologies are described and compared. All proposed schemes use the voltage and current models connected in parallel or in series...

  8. Control of frequency converters for wind power systems with doubly fed asynchronous generators; Regelung von Frequenzumrichtern fuer Windenergieanlagen mit doppelt gespeistem Asynchrongenerator

    Energy Technology Data Exchange (ETDEWEB)

    Engelhardt, Stephan [Woodward SEG GmbH und Co. KG, Kempen (Germany)

    2007-07-01

    Modern wind energy systems are characterized by an extensive use of power electronics. Using complex converter systems is technically and commercially very attractive as it allows an optimized operation of the wind turbine in regard to efficiency, reduced stress to the drive train due to variable speed and feeding wind power with high quality into the grid. For some years wind energy systems with frequency converter and doubly fed asynchronous generator have the biggest market share. The main requirements from grid codes regarding fault ride through operation will be summarized and enhanced control algorithms for this special type of system will be presented. (orig.)

  9. Petrophilic, Fe(III Reducing Exoelectrogen Citrobacter sp. KVM11, Isolated From Hydrocarbon Fed Microbial Electrochemical Remediation Systems

    Directory of Open Access Journals (Sweden)

    Krishnaveni Venkidusamy

    2018-03-01

    Full Text Available Exoelectrogenic biofilms capable of extracellular electron transfer are important in advanced technologies such as those used in microbial electrochemical remediation systems (MERS Few bacterial strains have been, nevertheless, obtained from MERS exoelectrogenic biofilms and characterized for bioremediation potential. Here we report the identification of one such bacterial strain, Citrobacter sp. KVM11, a petrophilic, iron reducing bacterial strain isolated from hydrocarbon fed MERS, producing anodic currents in microbial electrochemical systems. Fe(III reduction of 90.01 ± 0.43% was observed during 5 weeks of incubation with Fe(III supplemented liquid cultures. Biodegradation screening assays showed that the hydrocarbon degradation had been carried out by metabolically active cells accompanied by growth. The characteristic feature of diazo dye decolorization was used as a simple criterion for evaluating the electrochemical activity in the candidate microbe. The electrochemical activities of the strain KVM11 were characterized in a single chamber fuel cell and three electrode electrochemical cells. The inoculation of strain KVM11 amended with acetate and citrate as the sole carbon and energy sources has resulted in an increase in anodic currents (maximum current density of 212 ± 3 and 359 ± mA/m2 with respective coulombic efficiencies of 19.5 and 34.9% in a single chamber fuel cells. Cyclic voltammetry studies showed that anaerobically grown cells of strain KVM11 are electrochemically active whereas aerobically grown cells lacked the electrochemical activity. Electrobioremediation potential of the strain KVM11 was investigated in hydrocarbonoclastic and dye detoxification conditions using MERS. About 89.60% of 400 mg l-1 azo dye was removed during the first 24 h of operation and it reached below detection limits by the end of the batch operation (60 h. Current generation and biodegradation capabilities of strain KVM11 were examined using an

  10. Petrophilic, Fe(III) Reducing Exoelectrogen Citrobacter sp. KVM11, Isolated From Hydrocarbon Fed Microbial Electrochemical Remediation Systems

    Science.gov (United States)

    Venkidusamy, Krishnaveni; Hari, Ananda Rao; Megharaj, Mallavarapu

    2018-01-01

    Exoelectrogenic biofilms capable of extracellular electron transfer are important in advanced technologies such as those used in microbial electrochemical remediation systems (MERS) Few bacterial strains have been, nevertheless, obtained from MERS exoelectrogenic biofilms and characterized for bioremediation potential. Here we report the identification of one such bacterial strain, Citrobacter sp. KVM11, a petrophilic, iron reducing bacterial strain isolated from hydrocarbon fed MERS, producing anodic currents in microbial electrochemical systems. Fe(III) reduction of 90.01 ± 0.43% was observed during 5 weeks of incubation with Fe(III) supplemented liquid cultures. Biodegradation screening assays showed that the hydrocarbon degradation had been carried out by metabolically active cells accompanied by growth. The characteristic feature of diazo dye decolorization was used as a simple criterion for evaluating the electrochemical activity in the candidate microbe. The electrochemical activities of the strain KVM11 were characterized in a single chamber fuel cell and three electrode electrochemical cells. The inoculation of strain KVM11 amended with acetate and citrate as the sole carbon and energy sources has resulted in an increase in anodic currents (maximum current density) of 212 ± 3 and 359 ± mA/m2 with respective coulombic efficiencies of 19.5 and 34.9% in a single chamber fuel cells. Cyclic voltammetry studies showed that anaerobically grown cells of strain KVM11 are electrochemically active whereas aerobically grown cells lacked the electrochemical activity. Electrobioremediation potential of the strain KVM11 was investigated in hydrocarbonoclastic and dye detoxification conditions using MERS. About 89.60% of 400 mg l-1 azo dye was removed during the first 24 h of operation and it reached below detection limits by the end of the batch operation (60 h). Current generation and biodegradation capabilities of strain KVM11 were examined using an initial

  11. Development of individual semiconductor nanowire for bioelectrochemical device at low overpotential conditions

    Energy Technology Data Exchange (ETDEWEB)

    Crespilho, Frank N.; Lanfredi, Alexandre J.C. [Universidade Federal do ABC (UFABC), Santo Andre 09210-170 (Brazil); Leite, Edson R.; Chiquito, Adenilson J. [Universidade Federal do Sao Carlos (UFSCar), Sao Carlos, SP (Brazil)

    2009-09-15

    In this work we report the bioelectrochemical study using an individual indium tin oxide (ITO) nanowire (ITO-NW) electrode modified with glucose oxidase enzyme (GOx), in which the enzymatic activity and the biocatalytic activity was evaluated. The main objective is to show that at low overpotential condition, semiconductor NW can be used as an electron donor during biocatalytic process. We demonstrate the possibility of immobilizing an ITO-NW electrode on gold contacts deposited on top of a microchip (oxidized Si wafer). A protective polymer layer containing an aperture over the sample area was photolithographically deposited over the microchip to isolate the metallic contacts. For H{sub 2}O{sub 2} reduction during the biocatalysis at ITO-NWs surface, with {eta} << 50 mV, normal linear behavior is not observed and an exponential current is evident, similar to n-p semiconductor junction behavior. These results can open new tools for studying redox enzymes at the single-molecule level, and the device described here is very promising as a candidate for further exploration in bioelectrochemical devices, such as biofuel cells and biosensors. (author)

  12. Longitudinal zonation of macroinvertebrates in an Ecuadorian glacier-fed stream: do tropical glacial systems fit the temperate model?

    DEFF Research Database (Denmark)

    Jacobsen, D.; Dangles, O.; Andino, P.

    2010-01-01

    P>1. The ecology of glacier-fed streams at temperate latitudes has been intensely studied in recent years, leading to the development of a well-validated conceptual model on the longitudinal distribution of macroinvertebrate communities downstream of the glacier margin (Freshwater Biology, 2001a...... of the equator in the Ecuadorian Andes. Our goal was to study the longitudinal distribution of the fauna in relation to environmental factors and to compare this with the conceptual model based on temperate-arctic glacier-fed streams. 3. Total density of invertebrates differed considerably at the two highest...... was numerous at the highest sites but became much less important further downstream. The Orthocladiinae were important both in numbers and species at all sites, while Diamesinae were numerous only in the middle of the reach studied and were completely absent from the upper three sites. The limited importance...

  13. Sizing of the thermal and electrical systems for an FED bundle divertor design with MgO insulation

    International Nuclear Information System (INIS)

    Schultz, J.H.

    1981-01-01

    The high-order dependence of toroidal ripple from a bundle divertor on the magnet shield thickness increases the desirability of a magnet technology with minimal shielding requirements. A jacketed conductor with MgO powder insulation has been used successfully in highly irradiated environments. Its properties and limitations are described. A thermal and electrical sizing code has been developed for magnet design with this technology. Two design examples for ETF and FED missions show reduced recirculating power from previously reported designs

  14. Effect of FYM, potassium and zinc on phenology and grain yield of wheat in rain fed cropping systems

    International Nuclear Information System (INIS)

    Nawab, K.; Amanullah; Arif, M.; Shah, P.; Khan, M.A.; Khan, K.

    2011-01-01

    Little work has been done on potassium (K) and zinc (Zn) in combination with farm yard manure (FYM) under rain fed conditions of NWFP. This study was designed to examine the effects of un-irrigated cropping patterns and organic and in-organic fertilizers on wheat crop. Field experiments were conducted to investigate the effect of cropping patterns and farm yard manure, potassium and zinc on phenology and grain yield of wheat under rain fed (barani or un-irrigated) conditions at Agricultural Research Station, Serai Naurang Bannu for two years during 2001-02 and 2002-03. The experiment was designed in RCB design with split arrangements. Two factors were studied in the experiment. Effects of five cropping patterns i.e., fallow-wheat, groundnut-wheat, mungbean-wheat, sorghum-wheat and pigeon pea-wheat and three organic and in-organic fertilizers on subsequent wheat crop were observed. Data revealed that both the cropping patterns and manures/fertilizers had non-significant effect on days to anthesis, seed fill duration and days to maturity of wheat. Highest grain yield (3194 kg ha/sup -1/ wheat following mungbean produced more yield and wheat following groundnut produced less yield under dry land conditions. The present findings revealed that pigeon pea-wheat cropping pattern seems to be more sustainable in terms of yield under rain fed conditions and use of FYM, K and Zn should be included in integrated crop management approaches for sustainable crop production. (Author)

  15. Predictive modelling of chromium removal using multiple linear and nonlinear regression with special emphasis on operating parameters of bioelectrochemical reactor.

    Science.gov (United States)

    More, Anand Govind; Gupta, Sunil Kumar

    2018-03-24

    Bioelectrochemical system (BES) is a novel, self-sustaining metal removal technology functioning on the utilization of chemical energy of organic matter with the help of microorganisms. Experimental trials of two chambered BES reactor were conducted with varying substrate concentration using sodium acetate (500 mg/L to 2000 mg/L COD) and different initial chromium concentration (Cr i ) (10-100 mg/L) at different cathode pH (pH 1-7). In the current study mathematical models based on multiple linear regression (MLR) and non-linear regression (NLR) approach were developed using laboratory experimental data for determining chromium removal efficiency (CRE) in the cathode chamber of BES. Substrate concentration, rate of substrate consumption, Cr i , pH, temperature and hydraulic retention time (HRT) were the operating process parameters of the reactor considered for development of the proposed models. MLR showed a better correlation coefficient (0.972) as compared to NLR (0.952). Validation of the models using t-test analysis revealed unbiasedness of both the models, with t critical value (2.04) greater than t-calculated values for MLR (-0.708) and NLR (-0.86). The root-mean-square error (RMSE) for MLR and NLR were 5.06 % and 7.45 %, respectively. Comparison between both models suggested MLR to be best suited model for predicting the chromium removal behavior using the BES technology to specify a set of operating conditions for BES. Modelling the behavior of CRE will be helpful for scale up of BES technology at industrial level. Copyright © 2018 The Society for Biotechnology, Japan. Published by Elsevier B.V. All rights reserved.

  16. Pressure-Fed LOX/LCH4 Reaction Control System for Spacecraft: Transient Modeling and Thermal Vacuum Hotfire Test Results

    Science.gov (United States)

    Atwell, Matthew J.; Hurlbert, Eric A.; Melcher, J. C.; Morehead, Robert L.

    2017-01-01

    An integrated cryogenic liquid oxygen, liquid methane (LOX/LCH4) reaction control system (RCS) was tested at NASA Glenn Research Center's Plum Brook Station in the Spacecraft Propulsion Research Facility (B-2) under vacuum and thermal vacuum conditions. The RCS is a subsystem of the Integrated Cryogenic Propulsion Test Article (ICPTA), a pressure-fed LOX/LCH4 propulsion system composed of a single 2,800 lbf main engine, two 28 lbf RCS engines, and two 7 lbf RCS engines. Propellants are stored in four 48 inch diameter 5083 aluminum tanks that feed both the main engine and RCS engines in parallel. Helium stored cryogenically in a composite overwrapped pressure vessel (COPV) flows through a heat exchanger on the main engine before being used to pressurize the propellant tanks to a design operating pressure of 325 psi. The ICPTA is capable of simultaneous main engine and RCS operation. The RCS engines utilize a coil-on-plug (COP) ignition system designed for operation in a vacuum environment, eliminating corona discharge issues associated with a high voltage lead. There are two RCS pods on the ICPTA, with two engines on each pod. One of these two engines is a heritage flight engine from Project Morpheus. Its sea level nozzle was removed and replaced by an 85:1 nozzle machined using Inconel 718, resulting in a maximum thrust of 28 lbf under altitude conditions. The other engine is a scaled down version of the 28 lbf engine, designed to match the core and overall mixture ratios as well as other injector characteristics. This engine can produce a maximum thrust of 7 lbf with an 85:1 nozzle that was additively manufactured using Inconel 718. Both engines are film-cooled and capable of limited duration gas-gas and gas-liquid operation, as well as steady-state liquid-liquid operation. Each pod contains one of each version, such that two engines of the same thrust level can be fired as a couple on opposite pods. The RCS feed system is composed of symmetrical 3/8 inch lines

  17. Consumer acceptance of eggs from Hy-Line Brown layers fed soybean or soybean-free diets using cage or free-range rearing systems.

    Science.gov (United States)

    Al-Ajeeli, M N; Miller, R K; Leyva, H; Hashim, M M; Abdaljaleel, R A; Jameel, Y; Bailey, C A

    2018-05-01

    Consumers have begun to awaken to the food on their plates with respect to human health and the environment, as well as animal welfare. They have become more demanding about what they buy or prefer in their food, such as soy-free, gluten-free, or organic products. The objective of this study was to evaluate consumer acceptance of eggs from hens fed soybean meal or soybean-free diets utilizing cottonseed meal and distillers' dried grains, using cage or free-range rearing systems. All eggs were stored at the sensory lab at Texas A&M University (TAMU) for a d prior to each test at 4°C. A panel of consumers (n = 60) made up of TAMU students, faculty, and staff, ages 18 to 50, were recruited to evaluate consumer acceptance based on 2 tests using scrambled and hard cooked eggs. Samples were placed in separate weigh boats labeled with 3-digit codes to avoid visual bias. Sensory ballots were based on overall like or dislike of flavor, texture, odor, and color using the 9-point hedonic scales. For scrambled eggs, flavor did not differ (P > 0.05), but texture liking was higher (P = 0.064) for scrambled eggs from the soybean-free diet (7.08) vs. scrambled eggs from the soybean meal diet (6.65). With respect to the hard cooked eggs, the consumer panel preferred the flavor of the eggs from the caged rearing system (7.11) vs. eggs from the free-range system (6.60; P = 0.014). Consumers liked the texture (P = 0.018) for eggs collected from hens fed soybean meal (6.91) vs. eggs from hens fed the soybean-free diet (6.30).

  18. Improvement of small-signal stability of power system by controlling doubly fed induction generators of a large-capacity wind farm

    Directory of Open Access Journals (Sweden)

    Tomohiro Adachi

    2016-01-01

    Full Text Available Many wind turbine generations have been installed into power systems around the world, where in recent years doubly fed induction generator (DFIG attracts a lot of attentions because of its efficiency and controllability. However, the DFIG is connected to the power system through inverters and originally does not have an ability to release the kinetic energy of the rotor or resorb the surplus power of the power system as the kinetic energy. Therefore, it has not been made clear how the DFIGs have an influence on small-signal stability in power systems. In this paper, we propose a control scheme of the DFIG and analyse its effect on the small-signal stability of the power system by eigenvalue calculations and time-domain simulations.

  19. Bioelectrochemical control of neural cell development on conducting polymers.

    Science.gov (United States)

    Collazos-Castro, Jorge E; Polo, José L; Hernández-Labrado, Gabriel R; Padial-Cañete, Vanesa; García-Rama, Concepción

    2010-12-01

    Electrically conducting polymers hold promise for developing advanced neuroprostheses, bionic systems and neural repair devices. Among them, poly(3, 4-ethylenedioxythiophene) doped with polystyrene sulfonate (PEDOT:PSS) exhibits superior physicochemical properties but biocompatibility issues have limited its use. We describe combinations of electrochemical and molecule self-assembling methods to consistently control neural cell development on PEDOT:PSS while maintaining very low interfacial impedance. Electro-adsorbed polylysine enabled long-term neuronal survival and growth on the nanostructured polymer. Neurite extension was strongly inhibited by an additional layer of PSS or heparin, which in turn could be either removed electrically or further coated with spermine to activate cell growth. Binding basic fibroblast growth factor (bFGF) to the heparin layer inhibited neurons but promoted proliferation and migration of precursor cells. This methodology may orchestrate neural cell behavior on electroactive polymers, thus improving cell/electrode communication in prosthetic devices and providing a platform for tissue repair strategies. Copyright © 2010 Elsevier Ltd. All rights reserved.

  20. Ethanol production from Sorghum bicolor using both separate and simultaneous saccharification and fermentation in batch and fed batch systems

    DEFF Research Database (Denmark)

    Mehmood, Sajid; Gulfraz, M.; Rana, N. F.

    2009-01-01

    The objective of this work was to find the best combination of different experimental conditions during pre-treatment, enzymatic saccharification, detoxification of inhibitors and fermentation of Sorghum bicolor straw for ethanol production. The optimization of pre-treatment using different...... were used in order to increase the monomeric sugar during enzymatic hydrolysis and it has been observed that the addition of these surfactants contributed significantly in cellulosic conversion but no effect was shown on hemicellulosic hydrolysis. Fermentability of hydrolyzate was tested using...... Saccharomyces cerevisiae Ethanol Red (TM) and it was observed that simultaneous saccharification and fermentation ( SSF) with both batch and fed batch resulted in better ethanol yield as compared to separate hydrolysis and fermentation ( SHF). Detoxification of furan during SHF facilitated reduction...

  1. Feed intake, gastrointestinal system and body composition in reindeer calves fed early harvested first cut timothy silage (Phleum pratense

    Directory of Open Access Journals (Sweden)

    Harri J. Norberg

    1998-02-01

    Full Text Available Early harvested first cut (EFC timothy silage was fed to five reindeer calves (Rangifer tarandus tarandus L. taken from their natural summer pasture and brought to Tromsø for feeding trial. The calves were housed indoors in metabolism cages and fed EFC timothy silage ad lib. during the trial, which lasted from late November 1994 until the end of February 1995, when animals subsequently were slaughtered. Daily feed intake, gastrointestinal (GI anatomy, body weight and body composition of the animals were examined. Timothy silage {Phleum praténse was harvested 21 June, 1994 in Tromsø, prewilted and stored as round bales containing 97% leaves. The EFC silage contained 42.1% dry matter (DM, and 18.1% crude protein, 20.7% cellulose, 16.9% hemicellulose and 28.0% water soluble carbohydrates (WSC of DM. Mean feed intake (DM 24 hours after the trial started (day 1 was 9-4 g/kg body mass (BM (S.D.+ 3-9, while the mean daily DM intake during days 15-74 comprised 24.2 g/kg BM (S.D.+ 6.1. All animals except one gained body weight during the trial. The median (range BM at start and at slaughter was 48.5 kg (34.5¬58.0 kg and 50.0 kg (42.0-53.5 kg, respectively. Median (range carcass weight % of BM was 58.0% (51.2-58.7% and muscle index value 0.0132 (0.0106-0.0176. The median reticulo-rumen (RR content wet weight (WW was 4601 g (range 2697-5000 g comprising 9.3% of the BM, and 85.1% of the total gastrointestinal wet weight content. The median (range gastrointestinal tract weight was 14.1% of BM (10.7-16.4%. Based on feed intake during the trial and body composition at slaughtet we conclude that first cut timothy silage is suitable as emergency feed to reindeer, as long as it is harvested in early growth stage with high proportion of leaves.

  2. A Microstrip Patch-Fed Short Backfire Antenna for the Tracking and Data Relay Satellite System-Continuation (TDRSS-C) Multiple Access (MA) Array

    Science.gov (United States)

    Nessel, James A.; Kory, Carol L.; Lambert, Kevin M.; Acosta, Roberto J.

    2006-01-01

    Short Backfire Antennas (SBAs) are widely utilized for mobile satellite communications, tracking, telemetry, and wireless local area network (WLAN) applications due to their compact structure and excellent radiation characteristics [1-3]. Typically, these SBA s consist of an excitation element (i.e., a half-wavelength dipole), a reflective bottom plane, a planar sub-reflector located above the "exciter", and an outer circular rim. This configuration is capable of achieving gains on the order of 13-15 dBi, but with relatively narrow bandwidths (approx.3%-5%), making it incompatible with the requirements of the next generation enhanced Tracking and Data Relay Satellite System-Continuation (TDRSS-C) Multiple Access (MA) array [1]. Several attempts have been made to enhance the bandwidth performance of the common dipole-fed SBA by employing various other feeding mechanisms (e.g., waveguide, slot) with moderate success [4-5]. In this paper, a novel method of using a microstrip patch is employed for the first time to excite an SBA. The patch element is fed via two H-shaped slots electromagnetically coupled to a broadband hybrid coupler to maintain a wide bandwidth, as well as provide for dual circular polarization capabilities.

  3. Biotic diversity of benthic macroinvertebrates at contrasting glacier-fed systems in Patagonia Mountains: The role of environmental heterogeneity facing global warming.

    Science.gov (United States)

    Miserendino, María Laura; Brand, Cecilia; Epele, Luis B; Di Prinzio, Cecilia Y; Omad, Guillermo H; Archangelsky, Miguel; Martínez, Oscar; Kutschker, Adriana M

    2018-05-01

    Patagonia is by far the largest glacierized area in South America. However, little is known about ecology, functioning and biodiversity of glacier-fed streams facing global warming. We investigated changes in environmental features and macroinvertebrate communities along a longitudinal gradient of glacier influence of two Patagonian systems that differ in glacier cover magnitude and the spatial sequence of lotic and lentic phases. Both glaciers, Torrecillas (~5.5km 2 , Torrecillas system) and Cónico (~0.44km 2 , Baggilt system), are retreating. Longitudinal distribution of benthic invertebrates partially fitted to predictions for glacierized temperate systems, with Diamesinae spp. dominating at closest sites to the Cónico, and Orthocladiinae increasing downstream, but patterns were unclear at Torrecillas. Generalized Linear Model identified chlorophyll a and conductivity as having significant effect on richness and density respectively at Torrecillas; detritus biomass and gravel influenced species richness, and boulder percentage and water temperature affected density, at Baggilt. Canonical Correspondence Analyses integrating benthic biota and environmental variables revealed that a higher environmental heterogeneity at Baggilt, related with spatial dimension (unshaded/shaded reaches, wetland reaches), local resources (detritus, bryophytes) and temperature, probably explained the unexpected high richness in benthic assemblages (67 taxa). Environmental conditions imposed by the lake outlet (proglacial) at Torrecillas resulted in a less diverse community (31 taxa). Finally our results suggest that these isolated, small glacier-fed streams typical of the Patagonian landscape appear highly vulnerable to global warming. Endemic elements could disappear at upper segments being replaced by other species common at rhithral environments, which might increase local diversity (alfa diversity) but decrease regional diversity (gamma diversity). From an ecosystem perspective

  4. Dual-Input Soft-Switched DC-DC Converter with Isolated Current-Fed Half-Bridge and Voltage-Fed Full-Bridge for Fuel Cell or Photovoltaic Systems

    DEFF Research Database (Denmark)

    Zhang, Zhe; Thomsen, Ole Cornelius; Andersen, Michael A. E.

    2013-01-01

    integrate a current-fed boost half-bridge (BHB) and a full-bridge (FB) into one equivalent circuit configuration which has dual-input ability and additionally it can reduce the number of the power devices. With the phase-shift control, it can achieve zero-voltage switching turn-on of active switches...... power rating are built up and tested to demonstrate the effectiveness of the proposed converter topology....

  5. Bioelectrochemical Integration of Waste Heat Recovery, Waste-to- Energy Conversion, and Waste-to-Chemical Conversion with Industrial Gas and Chemical Manufacturing Processes

    Energy Technology Data Exchange (ETDEWEB)

    Mac Dougall, James [Air Products and Chemicals, Inc., Allentown, PA (United States)

    2016-02-05

    Many U.S. manufacturing facilities generate unrecovered, low-grade waste heat, and also generate or are located near organic-content waste effluents. Bioelectrochemical systems, such as microbial fuel cells and microbial electrolysis cells, provide a means to convert organic-content effluents into electric power and useful chemical products. A novel biochemical electrical system for industrial manufacturing processes uniquely integrates both waste heat recovery and waste effluent conversion, thereby significantly reducing manufacturing energy requirements. This project will enable the further development of this technology so that it can be applied across a wide variety of US manufacturing segments, including the chemical, food, pharmaceutical, refinery, and pulp and paper industries. It is conservatively estimated that adoption of this technology could provide nearly 40 TBtu/yr of energy, or more than 1% of the U.S. total industrial electricity use, while reducing CO2 emissions by more than 6 million tons per year. Commercialization of this technology will make a significant contribution to DOE’s Industrial Technology Program goals for doubling energy efficiency and providing a more robust and competitive domestic manufacturing base.

  6. Theoretical analysis of a biogas-fed PEMFC system with different hydrogen purifications: Conventional and membrane-based water gas shift processes

    International Nuclear Information System (INIS)

    Authayanun, Suthida; Aunsup, Pounyaporn; Patcharavorachot, Yaneeporn; Arpornwichanop, Amornchai

    2014-01-01

    Highlights: • Thermodynamic analysis of the biogas-fed PEMFC system is performed. • Conventional and membrane-based WGS processes for H 2 purification are studied. • A flowsheet model of the PEMFC system is developed. • Effect of key parameters on yields of H 2 and carbon in the biogas reformer is shown. • Performance of PEMFC systems with different H 2 purification processes is analyzed. - Abstract: This study presents a thermodynamic analysis of biogas reforming and proton electrolyte membrane fuel cell (PEMFC) integrated process with different hydrogen purifications: conventional and membrane-based water gas shift processes. The aim is to determine the optimal reforming process for hydrogen production from biogas in the PEMFC system. The formation of carbon is concerned in the hydrogen production. The simulation results show that increases in the steam-to-methane ratio and reformer temperature can improve the hydrogen yield and reduce the carbon formation. From the performance analysis, it is found that when the PEMFC is operated at high temperature and fuel utilization, the overall system efficiency enhances. The performance of the PEMFC system with the installation of a water gas shift membrane unit in the hydrogen purification step is slightly increased, compared with a conventional process

  7. An approach to hydrogeological modeling of a large system of groundwater-fed lakes and wetlands in the Nebraska Sand Hills, USA

    Science.gov (United States)

    Rossman, Nathan R.; Zlotnik, Vitaly A.; Rowe, Clinton M.

    2018-05-01

    The feasibility of a hydrogeological modeling approach to simulate several thousand shallow groundwater-fed lakes and wetlands without explicitly considering their connection with groundwater is investigated at the regional scale ( 40,000 km2) through an application in the semi-arid Nebraska Sand Hills (NSH), USA. Hydraulic heads are compared to local land-surface elevations from a digital elevation model (DEM) within a geographic information system to assess locations of lakes and wetlands. The water bodies are inferred where hydraulic heads exceed, or are above a certain depth below, the land surface. Numbers of lakes and/or wetlands are determined via image cluster analysis applied to the same 30-m grid as the DEM after interpolating both simulated and estimated heads. The regional water-table map was used for groundwater model calibration, considering MODIS-based net groundwater recharge data. Resulting values of simulated total baseflow to interior streams are within 1% of observed values. Locations, areas, and numbers of simulated lakes and wetlands are compared with Landsat 2005 survey data and with areas of lakes from a 1979-1980 Landsat survey and the National Hydrography Dataset. This simplified process-based modeling approach avoids the need for field-based morphology or water-budget data from individual lakes or wetlands, or determination of lake-groundwater exchanges, yet it reproduces observed lake-wetland characteristics at regional groundwater management scales. A better understanding of the NSH hydrogeology is attained, and the approach shows promise for use in simulations of groundwater-fed lake and wetland characteristics in other large groundwater systems.

  8. Polarized electrode enhances biological direct interspecies electron transfer for methane production in upflow anaerobic bioelectrochemical reactor.

    Science.gov (United States)

    Feng, Qing; Song, Young-Chae; Yoo, Kyuseon; Kuppanan, Nanthakumar; Subudhi, Sanjukta; Lal, Banwari

    2018-08-01

    The influence of polarized electrodes on the methane production, which depends on the sludge concentration, was investigated in upflow anaerobic bioelectrochemical (UABE) reactor. When the polarized electrode was placed in the bottom zone with a high sludge concentration, the methane production was 5.34 L/L.d, which was 53% higher than upflow anaerobic sludge blanket (UASB) reactor. However, the methane production was reduced to 4.34 L/L.d by placing the electrode in the upper zone of the UABE reactor with lower sludge concentration. In the UABE reactor, the methane production was mainly improved by the enhanced biological direct interspecies electron transfer (bDIET) pathway, and the methane production via the electrode was a minor fraction of less than 4% of total methane production. The polarized electrodes that placed in the bottom zone with a high sludge concentration enhance the bDIET for methane production in the UABE reactor and greatly improve the methane production. Copyright © 2018. Published by Elsevier Ltd.

  9. Bioelectrochemically-assisted anaerobic composting process enhancing compost maturity of dewatered sludge with synchronous electricity generation.

    Science.gov (United States)

    Yu, Hang; Jiang, Junqiu; Zhao, Qingliang; Wang, Kun; Zhang, Yunshu; Zheng, Zhen; Hao, Xiaodi

    2015-10-01

    Bioelectrochemically-assisted anaerobic composting process (AnCBE) with dewatered sludge as the anode fuel was constructed to accelerate composting of dewatered sludge, which could increase the quality of the compost and harvest electric energy in comparison with the traditional anaerobic composting (AnC). Results revealed that the AnCBE yielded a voltage of 0.60 ± 0.02 V, and total COD (TCOD) removal reached 19.8 ± 0.2% at the end of 35 d. The maximum power density was 5.6 W/m(3). At the end of composting, organic matter content (OM) reduction rate increased to 19.5 ± 0.2% in AnCBE and to 12.9 ± 0.1% in AnC. The fuzzy comprehensive assessment (FCA) result indicated that the membership degree of class I of AnCBE compost (0.64) was higher than that of AnC compost (0.44). It was demonstrated that electrogenesis in the AnCBE could improve the sludge stabilization degree, accelerate anaerobic composting process and enhance composting maturity with bioelectricity generation. Copyright © 2015 Elsevier Ltd. All rights reserved.

  10. Bio-electrochemical remediation of real field petroleum sludge as an electron donor with simultaneous power generation facilitates biotransformation of PAH: effect of substrate concentration.

    Science.gov (United States)

    Chandrasekhar, K; Venkata Mohan, S

    2012-04-01

    Remediation of real-field petroleum sludge was studied under self-induced electrogenic microenvironment with the function of variable organic loads (OLs) in bio-electrochemical treatment (BET) systems. Operation under various OLs documented marked influence on both electrogenic activity and remediation efficiency. Both total petroleum hydrocarbons (TPH) and its aromatic fraction documented higher removal with OL4 operation followed by OL3, OL2, OL1 and control. Self-induced biopotential and associated multiple bio-electrocatalytic reactions during BET operation facilitated biotransformation of higher ring aromatics (5-6) to lower ring aromatic (2-3) compounds. Asphaltenes and NSO fractions showed negligible removal during BET operation. Higher electrogenic activity was recorded at OL1 (343mV; 53.11mW/m(2), 100Ω) compared to other three OLs operation. Bioaugmentation to anodic microflora with anaerobic culture documented enhanced electrogenic activity at OL4 operation. Voltammetric profiles, Tafel analysis and VFA generation were in agreement with the observed power generation and degradation efficiency. Copyright © 2012 Elsevier Ltd. All rights reserved.

  11. Real-time simulation of a Doubly-Fed Induction Generator based wind power system on eMEGASimRTM Real-Time Digital Simulator

    Science.gov (United States)

    Boakye-Boateng, Nasir Abdulai

    The growing demand for wind power integration into the generation mix prompts the need to subject these systems to stringent performance requirements. This study sought to identify the required tools and procedures needed to perform real-time simulation studies of Doubly-Fed Induction Generator (DFIG) based wind generation systems as basis for performing more practical tests of reliability and performance for both grid-connected and islanded wind generation systems. The author focused on developing a platform for wind generation studies and in addition, the author tested the performance of two DFIG models on the platform real-time simulation model; an average SimpowerSystemsRTM DFIG wind turbine, and a detailed DFIG based wind turbine using ARTEMiSRTM components. The platform model implemented here consists of a high voltage transmission system with four integrated wind farm models consisting in total of 65 DFIG based wind turbines and it was developed and tested on OPAL-RT's eMEGASimRTM Real-Time Digital Simulator.

  12. In Vitro Growth of Curcuma longa L. in Response to Five Mineral Elements and Plant Density in Fed-Batch Culture Systems

    Science.gov (United States)

    El-Hawaz, Rabia F.; Bridges, William C.; Adelberg, Jeffrey W.

    2015-01-01

    Plant density was varied with P, Ca, Mg, and KNO3 in a multifactor experiment to improve Curcuma longa L. micropropagation, biomass and microrhizome development in fed-batch liquid culture. The experiment had two paired D-optimal designs, testing sucrose fed-batch and nutrient sucrose fed-batch techniques. When sucrose became depleted, volume was restored to 5% m/v sucrose in 200 ml of modified liquid MS medium by adding sucrose solutions. Similarly, nutrient sucrose fed-batch was restored to set points with double concentration of treatments’ macronutrient and MS micronutrient solutions, along with sucrose solutions. Changes in the amounts of water and sucrose supplementations were driven by the interaction of P and KNO3 concentrations. Increasing P from 1.25 to 6.25 mM increased both multiplication and biomass. The multiplication ratio was greatest in the nutrient sucrose fed-batch technique with the highest level of P, 6 buds/vessel, and the lowest level of Ca and KNO3. The highest density (18 buds/vessel) produced the highest fresh biomass at the highest concentrations of KNO3 and P with nutrient sucrose fed-batch, and moderate Ca and Mg concentrations. However, maximal rhizome dry biomass required highest P, sucrose fed-batch, and a moderate plant density. Different media formulations and fed-batch techniques were identified to maximize the propagation and storage organ responses. A single experimental design was used to optimize these dual purposes. PMID:25830292

  13. In vitro growth of Curcuma longa L. in response to five mineral elements and plant density in fed-batch culture systems.

    Science.gov (United States)

    El-Hawaz, Rabia F; Bridges, William C; Adelberg, Jeffrey W

    2015-01-01

    Plant density was varied with P, Ca, Mg, and KNO3 in a multifactor experiment to improve Curcuma longa L. micropropagation, biomass and microrhizome development in fed-batch liquid culture. The experiment had two paired D-optimal designs, testing sucrose fed-batch and nutrient sucrose fed-batch techniques. When sucrose became depleted, volume was restored to 5% m/v sucrose in 200 ml of modified liquid MS medium by adding sucrose solutions. Similarly, nutrient sucrose fed-batch was restored to set points with double concentration of treatments' macronutrient and MS micronutrient solutions, along with sucrose solutions. Changes in the amounts of water and sucrose supplementations were driven by the interaction of P and KNO3 concentrations. Increasing P from 1.25 to 6.25 mM increased both multiplication and biomass. The multiplication ratio was greatest in the nutrient sucrose fed-batch technique with the highest level of P, 6 buds/vessel, and the lowest level of Ca and KNO3. The highest density (18 buds/vessel) produced the highest fresh biomass at the highest concentrations of KNO3 and P with nutrient sucrose fed-batch, and moderate Ca and Mg concentrations. However, maximal rhizome dry biomass required highest P, sucrose fed-batch, and a moderate plant density. Different media formulations and fed-batch techniques were identified to maximize the propagation and storage organ responses. A single experimental design was used to optimize these dual purposes.

  14. Tritium transport and control in the FED

    International Nuclear Information System (INIS)

    Rogers, M.L.

    1981-01-01

    The tritium systems for the FED have three primary purposes. The first is to provide tritium and deuterium fuel for the reactor. This fuel can be new tritium or deuterium delivered to the plant site, or recycled DT from the reactor that must be processed before it can be recycled. The second purpose of the FED tritium systems is to provide state-of-the-art tritium handling to limit worker radiation exposure and to minimize tritium losses to the environment. The final major objective of the FED tritium systems is to provide an integrated system test of the tritium handling technology necessary to support the fusion reactor program. Every effort is being made to incorporate available information from the Tritium System Test Assembly (TSTA) at Los Alamos National Laboratory, the Tokamak Fusion Test Reactor (TFTR) tritium systems, and the tritium handling information generated within DOE for the past 20 years

  15. Production of oleic acid ethyl ester catalyzed by crude rice bran (Oryza sativa lipase in a modified fed-batch system: problem and its solution

    Directory of Open Access Journals (Sweden)

    Indro Prastowo

    2015-01-01

    Full Text Available A fed-batch system was modified for the enzymatic production of Oleic Acid Ethyl Ester (OAEE using rice bran (Oryza sativa lipase by retaining the substrate molar ratio (ethanol/oleic acid at 2.05: 1 during the reaction. It resulted in an increase in the ester conversion up to 76.8% in the first 6 h of the reaction, and then followed by a decrease from 76.8% to 22.9% in 6 h later. Meanwhile, the production of water in the reaction system also showed a similar trend to the trend of ester production. The water was hypothesized to lead lipase to reverse the reaction which resulted in a decrease in both (water and esters in the last 6 h of the reaction. In order to overcome the problem, zeolite powders (25 and 50 mg/ml were added into the reaction system at 5 h of the reaction. As the result, final ester conversions increased drastically up to 90 - 95.7% (1.17 – 1.24 times. The addition also proved a hypothesis that the water was involved in reducing the ester conversion in the last 6 h of the reaction. Thus, the combination was effective to produce the high final ester conversion.

  16. Optimal Operation of Photovoltaic System with a DC-DC Boost Converter FED SAF Using ICosφ Algorithm

    Directory of Open Access Journals (Sweden)

    G.Vijayakumar

    2014-07-01

    Full Text Available This paper presents an optimal utilization of Photovoltaic (PV solar system based Shunt Active Filter (PV-SAF for harmonic mitigation, real and reactive power compensation at the point of common coupling (PCC throughout the day. This PV system operated SAF reduces the energy consumption by disconnecting the utility grid from the load through semiconductor switches, when the PV system generates excessive or equal real power to the required load demand. However, the reduction of energy consumption is always desirable for the reduction of panel tariff and global warming gasses. The PV module is connected to the DC side of SAF through the DC-DC converter with fuzzy based Perturb & Observe (P&O Maximum Power Point Tracking (MPPT algorithm to eliminate the drawback of the conventional PV system by tracking maximum power point of the PV array is presented. The reference currents extract by the Fuzzy logic controller based ICosΦ control strategy. This proposed PV-SAF, if connected at the terminals of a small industry or a home or a small enlightening institution can avoid interruptible power supply, use of individual stabilizer and potential panel tariff over a 12 hour period. A MATLAB simulink is presented to validate the advantage of the proposed system.

  17. Production characteristics and body composition of juvenile cobia fed three different commercial diets in recirculating aquaculture systems

    Science.gov (United States)

    The effect of feeding three commercial diets on production characteristics and body composition of juvenile cobia Rachycentron canadum reared using recirculating aquaculture systems (RAS) was evaluated in a 56 d growth trial. Juvenile cobia (29.2 +/= 0.7 g, mean weight +/= SE) were stocked into thr...

  18. Design of a hybrid battery charger system fed by a wind-turbine and photovoltaic power generators.

    Science.gov (United States)

    Chang Chien, Jia-Ren; Tseng, Kuo-Ching; Yan, Bo-Yi

    2011-03-01

    This paper is aimed to develop a digital signal processor (DSP) for controlling a solar cell and wind-turbine hybrid charging system. The DSP consists of solar cells, a wind turbine, a lead acid battery, and a buck-boost converter. The solar cells and wind turbine serve as the system's main power sources and the battery as an energy storage element. The output powers of solar cells and wind turbine have large fluctuations with the weather and climate conditions. These unstable powers can be adjusted by a buck-boost converter and thus the most suitable output powers can be obtained. This study designs a booster by using a dsPIC30F4011 digital signal controller as a core processor. The DSP is controlled by the perturbation and observation methods to obtain an effective energy circuit with a full 100 W charging system. Also, this DSP can, day and night, be easily controlled and charged by a simple program, which can change the state of the system to reach a flexible application based on the reading weather conditions.

  19. Influence of genetic diversity on cause and effect relationships in lens culinaris germplasm under rain-fed eco-agricultural system

    International Nuclear Information System (INIS)

    Ilyas, M.; Arshad, M.; Ghafoor, A.

    2014-01-01

    Due to emerging demands of organic foods, lentil, one of the most primitive legumes was investigated for genetic diversity including cause and effect relationships among various clusters under eco-agricultural system. The 73 lentil genotypes were investigated for qualitative and quantitative traits to identify the potential lines under rain-fed conditions for organic farming using no chemical fertilizers for crop production. Variation existed for all the qualitative traits including orange cotyledon colour in 27 genotypes which is a preferred trait by Asian consumers including Pakistan. Five clusters revealed that average intra-clusters distances were more or less similar, whereas inter-cluster distance indicated higher level of genetic diversity. First three PCs contributed more than 3/4 of the variability and the results were in coordination with clustering pattern amongst 73 genotypes. The populations contributing the first PC were late in maturity possessed higher number of branches, pods, better biomass and grain yield. The PC/sub 2/ was more contributed by seeds pod-1 and seed diameter, whereas pod length and harvest index contributed 13% variability. The cause and effect relationships indicated differential response for selection of lentil genotypes suitable for eco-agricultural system within each cluster. (author)

  20. Phase 3 of a Brushless Doubly-Fed Machine System Development Program : Final Technical Report for Period January 1, 1992-June 30, 1993.

    Energy Technology Data Exchange (ETDEWEB)

    Alexander, Gerald C.; Spee, Rene; Wallace, Alan K.

    1993-12-31

    Since the inception of the BDFM development program in 1989, the value of BDFM technology has become apparent. The BDFM provides for adjustable speed, synchronous operation while keeping costs associated with the required power conversion equipment lower than in competing technologies. This provides for an advantage in initial as well as maintenance expenses over conventional drive system. Thus, the BDFM enables energy efficient, adjustable speed process control for applications where established drive technology has not been able to deliver satisfactory returns on investment. At the same time, the BDFM challenges conventional drive technologies in established markets by providing for improved performance at lower cost. BDFM converter rating is kept at a minimum, which significantly improves power quality at the utility interface over competing power conversion equipment. In summary, BDFM technology can be expected to provide significant benefits to utilities as well as their customers. This report discusses technical research and development activities related to Phase 3 of the Brushless Doubly-Fed Machine System Development Program, including work made possible by supplemental funds for laboratory improvement and prototype construction. Market research for the BDFM was provided by the College of Business at Oregon State University; market study results will be discussed in a separate report.

  1. Groundwater-fed irrigation impacts spatially distributed temporal scaling behavior of the natural system: a spatio-temporal framework for understanding water management impacts

    International Nuclear Information System (INIS)

    Condon, Laura E; Maxwell, Reed M

    2014-01-01

    Regional scale water management analysis increasingly relies on integrated modeling tools. Much recent work has focused on groundwater–surface water interactions and feedbacks. However, to our knowledge, no study has explicitly considered impacts of management operations on the temporal dynamics of the natural system. Here, we simulate twenty years of hourly moisture dependent, groundwater-fed irrigation using a three-dimensional, fully integrated, hydrologic model (ParFlow-CLM). Results highlight interconnections between irrigation demand, groundwater oscillation frequency and latent heat flux variability not previously demonstrated. Additionally, the three-dimensional model used allows for novel consideration of spatial patterns in temporal dynamics. Latent heat flux and water table depth both display spatial organization in temporal scaling, an important finding given the spatial homogeneity and weak scaling observed in atmospheric forcings. Pumping and irrigation amplify high frequency (sub-annual) variability while attenuating low frequency (inter-annual) variability. Irrigation also intensifies scaling within irrigated areas, essentially increasing temporal memory in both the surface and the subsurface. These findings demonstrate management impacts that extend beyond traditional water balance considerations to the fundamental behavior of the system itself. This is an important step to better understanding groundwater’s role as a buffer for natural variability and the impact that water management has on this capacity. (paper)

  2. Selecting optimal feast-to-famine ratio for a new polyhydroxyalkanoate (PHA) production system fed by valerate-dominant sludge hydrolysate.

    Science.gov (United States)

    Hao, Jiuxiao; Wang, Hui; Wang, Xiujin

    2018-04-01

    The feast-to-famine ratio (F/F) represents the extent of selective pressure during polyhydroxyalkanoate (PHA) culture selection. This study evaluated the effects of F/F on a new PHA production system by an enriched culture with valerate-dominant sludge hydrolysate and selected the optimal F/F. After the original F/F 1/3 was modified to 1/1, 1/2, 1/4, and 1/5, F/F did not affect their lengths of feast phase, but affected their biomass growth behaviors during the famine phase and PHA-producing abilities. The optimal F/F was 1/2, and compared with 1/3, it increased the maximal PHA content and the fraction of 3-hydroxyvalerate (3HV) and 3-hydroxy-2-methylvalerate (3H2MV) monomers, with higher productivity and better polymer properties. Although F/F 1/2 impaired the advantage of the dominant genus Delftia, it improved the PHA production rate while decreased biomass growth rate, meanwhile enhancing the utilization and conversion of valerate. These findings indicate that in contrast to previous studies using acetate-dominant substrate for PHA production, the new system fed by valerate-dominant substrate can adopt a higher F/F.

  3. The Oil-Spill Snorkel: an innovative bioelectrochemical approach to accelerate hydrocarbons biodegradation in marine sediments

    Directory of Open Access Journals (Sweden)

    Carolina eCruz Viggi

    2015-09-01

    Full Text Available This study presents the proof-of-concept of the Oil-Spill Snorkel: a novel bioelectrochemical approach to stimulate the oxidative biodegradation of petroleum hydrocarbons in sediments. The Oil-Spill Snorkel consists of a single conductive material (the snorkel positioned suitably to create an electrochemical connection between the anoxic zone (the contaminated sediment and the oxic zone (the overlying O2-containing water. The segment of the electrode buried within the sediment plays a role of anode, accepting electrons deriving from the oxidation of contaminants. Electrons flow through the snorkel up to the part exposed to the aerobic environment (the cathode, where they reduce oxygen to form water. Here we report the results of lab-scale microcosms setup with marine sediments and spiked with crude oil. Microcosms containing 1 or 3 graphite snorkels and controls (snorkel-free and autoclaved were monitored for over 400 days. Collectively, the results of this study confirmed that the snorkels accelerate oxidative reactions taking place within the sediment, as documented by a significant 1.7-fold increase (p=0.023, two-tailed t-test in the cumulative oxygen uptake and 1.4-fold increase (p=0.040 in the cumulative CO2 evolution in the microcosms containing 3 snorkels compared to snorkel-free controls. Accordingly, the initial rate of total petroleum hydrocarbons (TPH degradation was also substantially enhanced. Indeed, while after 200 days of incubation a negligible degradation of TPH was noticed in snorkel-free controls, a significant reduction of 12±1% (p=0.004 and 21±1% (p=0.001 was observed in microcosms containing 1 and 3 snorkels, respectively. Although, the Oil-Spill Snorkel potentially represents a groundbreaking alternative to more expensive remediation options, further research efforts are needed to clarify factors and conditions affecting the snorkel-driven biodegradation processes and to identify suitable configurations for field

  4. Growth and yield of rain fed wheat as affected by different tillage system integrated with glyphosate herbicide

    International Nuclear Information System (INIS)

    Ali, S.; Malik, M.A.; Khan, M.A.

    2016-01-01

    In rainfed areas, tillage is primarily done for moisture conservation and weed control. However, excessive tilling not only harms the soil health but also increases the cost of production. To find out the sustainable and economical tillage combination, response of wheat was studied under different tillage systems integrated with glyphosate herbicide through field experiments conducted at University Research Farm of Pir Mehr Ali Shah, Arid Agriculture University Rawalpindi, Pakistan during 2012-2014 for two consecutive seasons. Principal component analysis proved that the plant height, biological yield, grain yield and harvest index of wheat were highest in treatment where one moldboard plowing was done followed by eight cultivations without using glyphosate in fallow period, which might be due to vigorous growth of wheat in this tillage system having enhanced root proliferation and moisture conservation, thus allowing plants to extract more nutrients and water from the deeper soil layers; whereas, the number of tillers per square meter, number of spikelets per spike, 1000 grain weight and number of grains per spike of wheat were maximum where one moldboard plowing was done followed by two applications of glyphosate herbicide in fallow period, which might be due to vigorous growth of wheat in this tillage system during 1st year of experiment when unexpected high rainfall was occurred during crop growth stage. Cluster analysis also categorized these two treatments into same category on the base of all agronomic parameters studied. The highest yield (3.5132 t ha-1) and (3.1242 t ha-1) was obtained from where one moldboard plowing was done following eight cultivations without using glyphosate followed by the treatment where one moldboard plowing was done following four cultivations without using glyphosate, respectively and were statistically at par with each other. Therefore one moldboard plowing following four cultivations is recommended for taking higher and

  5. Effect of Short-Circuit Faults in the Back-to-Back Power Electronic Converter and Rotor Terminals on the Operational Behavior of the Doubly-Fed Induction Generator Wind Energy Conversion System

    Directory of Open Access Journals (Sweden)

    Dimitrios G. Giaourakis

    2015-02-01

    Full Text Available This paper deals with the operational behavior of the Doubly-Fed Induction Generator Wind Energy Conversion System under power electronic converter and rotor terminals faulty conditions. More specifically, the effect of the short-circuit fault both in one IGBT of the back-to-back power electronic converter and in rotor phases on the overall system behavior has been investigated via simulation using a system of 2 MW. Finally, the consequences of these faults have been evaluated.

  6. Real-Time Control of Active and Reactive Power for Doubly Fed Induction Generator (DFIG-Based Wind Energy Conversion System

    Directory of Open Access Journals (Sweden)

    Aman Abdulla Tanvir

    2015-09-01

    Full Text Available This paper presents the modeling, rapid control prototyping, and hardware-in-the-loop testing for real-time simulation and control of a grid-connected doubly fed induction generator (DFIG in a laboratory-size wind turbine emulator for wind energy conversation systems. The generator is modeled using the direct-quadrature rotating reference frame circuit along with the aligned stator flux, and the field-oriented control approach is applied for independent control of the active and reactive power and the DC-link voltage at the grid side. The control of the active, reactive power and the DC-link voltage are performed using a back-to-back converter at sub- and super-synchronous as well as at variable speeds. The control strategy is experimentally validated on an emulated wind turbine driven by the Opal-RT real-time simulator (OP5600 for simultaneous control of the DC-link voltage, active and reactive power.

  7. Humanized HLA-DR4 mice fed with the protozoan pathogen of oysters Perkinsus marinus (Dermo do not develop noticeable pathology but elicit systemic immunity.

    Directory of Open Access Journals (Sweden)

    Wathsala Wijayalath

    Full Text Available Perkinsus marinus (Phylum Perkinsozoa is a marine protozoan parasite responsible for "Dermo" disease in oysters, which has caused extensive damage to the shellfish industry and estuarine environment. The infection prevalence has been estimated in some areas to be as high as 100%, often causing death of infected oysters within 1-2 years post-infection. Human consumption of the parasites via infected oysters is thus likely to occur, but to our knowledge the effect of oral consumption of P. marinus has not been investigated in humans or other mammals. To address the question we used humanized mice expressing HLA-DR4 molecules and lacking expression of mouse MHC-class II molecules (DR4.EA(0 in such a way that CD4 T cell responses are solely restricted by the human HLA-DR4 molecule. The DR4.EA(0 mice did not develop diarrhea or any detectable pathology in the gastrointestinal tract or lungs following single or repeated feedings with live P. marinus parasites. Furthermore, lymphocyte populations in the gut associated lymphoid tissue and spleen were unaltered in the parasite-fed mice ruling out local or systemic inflammation. Notably, naïve DR4.EA(0 mice had antibodies (IgM and IgG reacting against P. marinus parasites whereas parasite specific T cell responses were undetectable. Feeding with P. marinus boosted the antibody responses and stimulated specific cellular (IFNγ immunity to the oyster parasite. Our data indicate the ability of P. marinus parasites to induce systemic immunity in DR4.EA(0 mice without causing noticeable pathology, and support rationale grounds for using genetically engineered P. marinus as a new oral vaccine platform to induce systemic immunity against infectious agents.

  8. Harmonic Distortion Performance of Multi Three-Phase SCR-Fed Drive Systems with Controlled DC-Link Current under Unbalanced Grid

    DEFF Research Database (Denmark)

    Soltani, Hamid; Davari, Pooya; Blaabjerg, Frede

    2017-01-01

    . In this paper, the main aim is to analyze the effects of the grid unbalanced voltage on the multi-unit three-phase ASDs with the Silicon-Controlled Rectifier (SCR)-fed front-end rectifiers, where the DC-link current is controlled utilizing an Electronic Inductor (EI) technique. In this respect, the main...

  9. Bioelectrochemical enhancement of methane production from highly concentrated food waste in a combined anaerobic digester and microbial electrolysis cell.

    Science.gov (United States)

    Park, Jungyu; Lee, Beom; Tian, Donjie; Jun, Hangbae

    2018-01-01

    A microbial electrolysis cell (MEC) is a promising technology for enhancing biogas production from an anaerobic digestion (AD) reactor. In this study, the effects of the MEC on the rate of methane production from food waste were examined by comparing an AD reactor with an AD reactor combined with a MEC (AD+MEC). The use of the MEC accelerated methane production and stabilization via rapid organic oxidation and rapid methanogenesis. Over the total experimental period, the methane production rate and stabilization time of the AD+MEC reactor were approximately 1.7 and 4.0 times faster than those of the AD reactor. Interestingly however, at the final steady state, the methane yields of both the reactors were similar to the theoretical maximum methane yield. Based on these results, the MEC did not increase the methane yield over the theoretical value, but accelerated methane production and stabilization by bioelectrochemical reactions. Copyright © 2017 Elsevier Ltd. All rights reserved.

  10. FUZZY SLIDING MODE CONTROLLER FOR DOUBLY FED ...

    African Journals Online (AJOL)

    2010-12-31

    Dec 31, 2010 ... against internal and external perturbations, but the FSMC is superior to ... controller, doubly fed induction motor, fuzzy logic control. 1. ... capabilities in accounting for modeling imprecision and bounded disturbances. It ..... To show the effect of the parameters uncertainties, we have simulated the system with.

  11. Evaluation of the performance of Hy-Line Brown laying hens fed soybean or soybean-free diets using cage or free-range rearing systems.

    Science.gov (United States)

    Al-Ajeeli, M N; Leyva-Jimenez, H; Abdaljaleel, R A; Jameel, Y; Hashim, M M; Archer, G; Bailey, C A

    2018-03-01

    This study evaluated egg production and quality variables of caged and free-range Hy-Line Brown laying hens fed soybean meal (SBM) and soybean-meal-free (SBMF) diets. Hens were randomly assigned to the same 2 dietary treatments within 3 location blocks. SBM and SBMF diets with equivalent calculated nutrient content were prepared based on Hy-Line Brown rearing guidelines. The SBMF diets utilized cottonseed meal, corn distillers dried grains with solubles, corn gluten meal, and wheat middlings in place of dehulled soybean meal. The experiment was conducted between August 2015 and January of 2016 within the TAMU Poultry Research Center and data analyzed over 6 consecutive 28-day periods. Data were analyzed as a split-plot with rearing systems designated whole plots and diets designated as subplots. Hens reared in the free-range rearing system peaked a couple of wk later than those hens within the more conventional indoor caged system, and cumulative production data were considerably more variable for hens raised in the free-range environment. Cumulative egg production, feed per dozen eggs and feed conversion ratio (g feed/g egg) were 92 ± 1.23 and 86 ± 1.84%, 1.45 ± 0.02 and 1.89 ± 0.05 kg, and 2.14 ± 0.04 and 2.77 ± 0.08 (P free-range rearing systems. Cumulative egg weight, feed per dozen eggs, and feed conversion ratio were 59.9 ± 0.59 and 56.5 ± 0.60 g, 1.57 ± 0.04 and 1.77 ± 0.05 kg, and 2.24 ± 0.06 and 2.67 ± 0.08 kg (P  0.05). With respect to egg quality, there were no differences in cumulative albumen height, Haugh unit, or breaking strength, but there was a significant rearing system by diet interaction for shell thickness, with the free-range hens averaging 40.77 ± 0.19 and 39.86 ± 0.31 μm (P free-range production is more variable than traditional closed-house cage systems based on standard errors, and SBMF diets containing cottonseed meal can be used in both caged and free-range production systems without

  12. Spontaneous modification of carbon surface with neutral red from its diazonium salts for bioelectrochemical systems.

    Science.gov (United States)

    Guo, Kun; Chen, Xin; Freguia, Stefano; Donose, Bogdan C

    2013-09-15

    This study introduces a novel and simple method to covalently graft neutral red (NR) onto carbon surfaces based on spontaneous reduction of in situ generated NR diazonium salts. Immobilization of neutral red on carbon surface was achieved by immersing carbon electrodes in NR-NaNO2-HCl solution. The functionalized electrodes were characterized by cyclic voltammetry (CV), atomic force microscope (AFM), and X-ray photoelectron spectroscopy (XPS). Results demonstrated that NR attached in this way retains high electrochemical activity and proved that NR was covalently bound to the carbon surface via the pathway of reduction of aryl diazonium salts. The NR-modified electrodes showed a good stability when stored in PBS solution in the dark. The current output of an acetate-oxidising microbial bioanode made of NR-modified graphite felts were 3.63±0.36 times higher than the unmodified electrodes, which indicates that covalently bound NR can act as electron transfer mediator to facilitate electron transfer from bacteria to electrodes. Copyright © 2013 Elsevier B.V. All rights reserved.

  13. Reference and counter electrode positions affect electrochemical characterization of bioanodes in different bioelectrochemical systems

    KAUST Repository

    Zhang, Fang; Liu, Jia; Ivanov, Ivan; Hatzell, Marta C.; Yang, Wulin; Ahn, Yongtae; Logan, Bruce E.

    2014-01-01

    in biofilm characteristics because the CVs were electrochemically independent of conditions resulting from changing CE to RE distances. Placing the RE outside of the current path enabled accurate bioanode characterization using CVs and EIS due to negligible

  14. Nanotechnology to rescue bacterial bidirectional extracellular electron transfer in bioelectrochemical systems

    KAUST Repository

    Kalathil, Shafeer

    2016-03-17

    An electrically active bacterium transports its metabolically generated electrons to insoluble substrates such as electrodes via a process known as extracellular electron transport (EET). Bacterial EET is a crucial process in the geochemical cycling of metals, bioremediation and bioenergy devices such as microbial fuel cells (MFCs). Recently, it has been found that electroactive bacteria can reverse their respiratory pathways by accepting electrons from a negatively poised electrode to produce high-value chemicals such as ethanol in a process termed as microbial electrosynthesis (MES). A poor electrical connection between bacteria and the electrode hinders the EET and MES processes significantly. Also, the bidirectional EET process is sluggish and needs to be improved drastically to extend its practical applications. Several attempts have been undertaken to improve the bidirectional EET by employing various advanced nanostructured materials such as carbon nanotubes and graphene. This review covers the recent progress in the bacterial bidirectional EET processes using advanced nanostructures in the light of current understandings of bacteria–nanomaterial interactions.

  15. Nanotechnology to rescue bacterial bidirectional extracellular electron transfer in bioelectrochemical systems

    KAUST Repository

    Kalathil, Shafeer; Pant, Deepak

    2016-01-01

    of metals, bioremediation and bioenergy devices such as microbial fuel cells (MFCs). Recently, it has been found that electroactive bacteria can reverse their respiratory pathways by accepting electrons from a negatively poised electrode to produce high

  16. Anodic ammonia oxidation to nitrogen gas catalyzed by mixed biofilms in bioelectrochemical systems

    International Nuclear Information System (INIS)

    Zhan, Guoqiang; Zhang, Lixia; Tao, Yong; Wang, Yujian; Zhu, Xiaoyu; Li, Daping

    2014-01-01

    In this paper we report ammonia oxidation to nitrogen gas using microbes as biocatalyst on the anode, with polarized electrode (+600 mV vs. Ag/AgCl) as electron acceptor. In batch experiments, the maximal rate of ammonia-N oxidation by the mixed culture was ∼ 60 mg L −1 d −1 , and nitrogen gas was the main products in anode compartment. Cyclic voltammetry for testing the electroactivity of the anodic biofilms revealed that an oxidation peak appeared at +600 mV (vs. Ag/AgCl), whereas the electrode without biofilms didn’t appear oxidation peak, indicating that the bioanode had good electroactivities for ammonia oxidation. Microbial community analysis of 16S rRNA genes based on high throughput sequencing indicated that the combination of the dominant genera of Nitrosomonas, Comamonas and Paracocus could be important for the electron transfer from ammonia oxidation to anode

  17. Simultaneous Robust Coordinated Damping Control of Power System Stabilizers (PSSs, Static Var Compensator (SVC and Doubly-Fed Induction Generator Power Oscillation Dampers (DFIG PODs in Multimachine Power Systems

    Directory of Open Access Journals (Sweden)

    Jian Zuo

    2017-04-01

    Full Text Available The potential of utilizing doubly-fed induction generator (DFIG-based wind farms to improve power system damping performance and to enhance small signal stability has been proposed by many researchers. However, the simultaneous coordinated tuning of a DFIG power oscillation damper (POD with other damping controllers is rarely involved. A simultaneous robust coordinated multiple damping controller design strategy for a power system incorporating power system stabilizer (PSS, static var compensator (SVC POD and DFIG POD is presented in this paper. This coordinated damping control design strategy is addressed as an eigenvalue-based optimization problem to increase the damping ratios of oscillation modes. Both local and inter-area electromechanical oscillation modes are intended in the optimization design process. Wide-area phasor measurement unit (PMU signals, selected by the joint modal controllability/ observability index, are utilized as SVC and DFIG POD feedback modulation signals to suppress inter-area oscillation modes. The robustness of the proposed coordinated design strategy is achieved by simultaneously considering multiple power flow situations and operating conditions. The recently proposed Grey Wolf optimizer (GWO algorithm is adopted to efficiently optimize the parameter values of multiple damping controllers. The feasibility and effectiveness of the proposed coordinated design strategy are demonstrated through frequency-domain eigenvalue analysis and nonlinear time-domain simulation studies in two modified benchmark test systems. Moreover, the dynamic response simulation results also validate the robustness of the recommended coordinated multiple damping controllers under various system operating conditions.

  18. FED, Geometry Input Generator for Program TRUMP

    International Nuclear Information System (INIS)

    Schauer, D.A.; Elrod, D.C.

    1996-01-01

    1 - Description of program or function: FED reduces the effort required to obtain the necessary geometric input for problems which are to be solved using the heat-transfer code, TRUMP (NESC 771). TRUMP calculates transient and steady-state temperature distributions in multidimensional systems. FED can properly zone any body of revolution in one, or three dimensions. 2 - Method of solution: The region of interest must first be divided into areas which may consist of a common material. The boundaries of these areas are the required FED input. Each area is subdivided into volume nodes, and the geometrical properties are calculated. Finally, FED connects the adjacent nodes to one another, using the proper surface area, interface distance, and, if specified, radiation form factor and interface conductance. 3 - Restrictions on the complexity of the problem: Rectangular bodies can only be approximated by using a very large radius of revolution compared to the total radial thickness and by considering only a small angular segment in the circumferential direction

  19. Anion-exchange membranes in electrochemical energy systems

    NARCIS (Netherlands)

    Varcoe, J.R.; Atanassov, P.; Dekel, D.R.; Herring, A.M.; Hickner, M.A.; Kohl, P.A.; Kucernak, A. R.; Mustain, W.E.; Nijmeijer, K.; Scott, Keith; Xu, Tongwen; Zhuang, Lin

    2014-01-01

    This article provides an up-to-date perspective on the use of anion-exchange membranes in fuel cells, electrolysers, redox flow batteries, reverse electrodialysis cells, and bioelectrochemical systems (e.g. microbial fuel cells). The aim is to highlight key concepts, misconceptions, the current

  20. Cellular muscle growth and molecular cloning and expression of growth-related gene of Malaysian Mahseer Tor tambroides larvae fed with live and formulated feeds in indoor nursery rearing system

    Directory of Open Access Journals (Sweden)

    Md. Asaduzzaman

    2017-02-01

    Full Text Available The influences of live and formulated feeds on growth performances, muscle fibers morphometry and muscle growth-related gene expression of Malaysian mahseer, Tor tambroides larvae were evaluated in indoor nursery rearing system. Quadruplicate groups of T. tambroides larvae (0.07 ± 0.01 g, mean ± SE were stocked in sixteen aquaria (60 × 30 × 30 cm, randomly arranged in four dietary treatments viz. larvae fed artemia (LA, moina (LM, daphnia (LD and formulated feed (FF with stocking density of 34 larvae per aquarium. The larvae were fed to visually near satiation in two equal feedings per day, seven days per week for 75 days. The growth-related parameters (mean weight gain and specific growth rate were significantly highest in treatment FF, followed by treatment LA and the lowest in treatment LD or LM. Histological observation and muscle morphometric analysis revealed that mosaic hyperplasia was observed after 50 days of the feeding trial. Hypertrophic (diameter class 50 = 40 > d ≤ 50 μm and class 60 = d > 50 μm, but not hyperplastic (diameter class ≤10 μm, muscle fibers frequencies were significantly highest in larvae fed FF compared to those fed live feeds. The entire open reading frame cDNA sequences of two important growth-related genes, myogenin and MyoD, were successfully amplified and cloned from T. tambroides larvae. The nucleotide sequences alignment using CLUSTAL W in BioEdit program of both MyoD and myogenin genes showed the sign of existence of isoforms and highly conserved with other cyprinid fishes. Real-time PCR data demonstrated that myogenin and MyoD gene expressions were significantly upregulated in larvae fed FF. The results of the present experiment concluded that the nursery rearing of T. tambroides larvae with formulated feed showed augmented muscle growth and upregulated growth-related gene expression than feeding live feeds.

  1. FedScope Employment Cubes

    Data.gov (United States)

    Office of Personnel Management — This raw data set provides Federal civilian employee population data. The scope of this raw data set includes all data elements used in the creation of the FedScope...

  2. Load ratio determines the ammonia recovery and energy input of an electrochemical system

    NARCIS (Netherlands)

    Rodríguez Arredondo, Mariana; Kuntke, Philipp; Heijne, Ter Annemiek; Hamelers, Hubertus V.M.; Buisman, Cees J.N.

    2017-01-01

    Complete removal and recovery of total ammonia nitrogen (TAN) from wastewaters in (bio)electrochemical systems has proven to be a challenge. The system performance depends on several factors, such as current density, TAN loading rate and pH. The interdependence among these factors is not well

  3. Effect of IOP based infusion system with and without balanced phaco tip on cumulative dissipated energy and estimated fluid usage in comparison to gravity fed infusion in torsional phacoemulsification.

    Science.gov (United States)

    Malik, Praveen K; Dewan, Taru; Patidar, Arun Kr; Sain, Ekta

    2017-01-01

    To evaluate the effect of three different combinations of tip designs and infusion systems in torsional phacoemulsification (INFINITI and CENTURION) in patients with cataract. According to the manufacturer, two unique improvements in the Centurion are: active fluid dynamic management system and use of an intrepid balanced tip. The study specifically aimed to evaluate the beneficial effects, if any, of change in tip design and infusion system individually and in combination on both per-operative parameters as well as endothelial health over 6 months. One hundred and twenty six consenting patients of grade 4.0-6.9 senile cataract were randomized into three groups for phacoemulsification: Group A ( n  = 42): Gravity fed infusion system and 45 0 Kelman miniflared ABS phaco tip; Group B ( n  = 42): intraocular pressure (IOP) based infusion system and 45 0 Kelman miniflared ABS phaco tip; Group C ( n  = 42): IOP based infusion system and 45 0 Intrepid balanced phaco tip. The cumulative dissipated energy (CDE), estimated fluid usage (EFU) and total aspiration time (TAT) were compared peroperatively. The endothelial parameters were followed up postoperatively for six months. The three arms were matched for age ( p  = 0.525), gender ( p  = 0.96) and grade of cataract ( p  = 0.177). Group C was associated with significant reductions in CDE ( p  = 0.001), EFU ( p  < 0.0005) as well as TAT ( p  = 0.001) in comparison to the other groups. All three groups had comparable baseline endothelial cell density ( p  = 0.876) and central corneal thickness ( p  = 0.561). On post-operative evaluation, although all groups were comparable till 3 months, by 6 months, the percentage losses in endothelial cell density were significantly lower in group C as compared to the other groups. Use of an IOP based phacoemulsification system in association with use of the Intrepid balanced tip reduces the CDE, EFU and TAT in comparison to a gravity fed system with a mini flared

  4. Silver-choline chloride modified graphene oxide: Novel nano-bioelectrochemical sensor for celecoxib detection and CCD-RSM model.

    Science.gov (United States)

    Parsaee, Zohreh; Karachi, Nima; Abrishamifar, Seyyed Milad; Kahkha, Mohammad Reza Rezaei; Razavi, Razieh

    2018-07-01

    In this study, silver nanoparticles modified choline chloride functionalized graphene oxide (AgNPs-ChCl-GO) was synthesized using sonochemical method and utilized as a bioelectrochemical sensor for detection of celecoxib (CEL). The characterization studies were ultimately performed in order to acheive a more complete understanding of the morphological and structural features of the AgNPs-ChCl-GO using different techniques including FT-IR, AFM, FE-SEM, EDX, and XRD. AgNPs-ChCl-GO demonstrated a significant improvement in the reduction activity of CEL due to the enhancement in the current response compared to the bare carbon paste electrode (CPE). The optimum experimental conditions, were optimized using central composite design (CCD) methodology. The differential pulse voltammetry (DPVs) showed an expanded linear dynamic ranges of 9.6 × 10 -9 -7.4 × 10 -7  M for celecoxib in Britton-Robinson buffer in pH 5.0 with. LOD (S/N = 3) and LOQ (S/N = 10) were obtained 2.51 × 10 -9  M and 6.58 × 10 -9  M respectively. AgNPs-ChCl-GO-carbon paste electrode exhibited suitable properties and high accuracy determination of celecoxib in the human plasma sample. Copyright © 2018 Elsevier B.V. All rights reserved.

  5. Bioelectrochemical recovery of waste-derived volatile fatty acids and production of hydrogen and alkali

    DEFF Research Database (Denmark)

    Zhang, Yifeng; Angelidaki, Irini

    2015-01-01

    Volatile fatty acids (VFA) are organic compounds of great importance for various industries and environmental processes. Fermentation and anaerobic digestion of organic wastes are promising alternative technologies for VFA production. However, one of the major challenges is development...... of sustainable downstream technologies for VFA recovery. In this study, an innovative microbial bipolar electrodialysis cell (MBEDC) was developed to meet the challenge of waste-derived VFA recovery, produce hydrogen and alkali, and potentially treat wastewater. The MBEDC was operated in fed-batch mode....... At an applied voltage of 1.2 V, a VFA recovery efficiency of 98.3%, H2 of 18.4 mL and alkali production presented as pH of 12.64 were obtained using synthetic fermentation broth. The applied voltage, initial VFA concentrations and composition were affecting the VFA recovery. The energy balance revealed that net...

  6. Higher insulin sensitivity in EDL muscle of rats fed a low-protein, high-carbohydrate diet inhibits the caspase-3 and ubiquitin-proteasome proteolytic systems but does not increase protein synthesis.

    Science.gov (United States)

    Dos Santos, Maísa Pavani; Batistela, Emanuele; Pereira, Mayara Peron; Paula-Gomes, Silvia; Zanon, Neusa Maria; Kettelhut, Isis do Carmo; Karatzaferi, Christina; Andrade, Claudia Marlise Balbinotti; de França, Suélem Aparecida; Baviera, Amanda Martins; Kawashita, Nair Honda

    2016-08-01

    Compared with the extensor digitorum longus (EDL) muscle of control rats (C), the EDL muscle of rats fed a low-protein, high-carbohydrate diet (LPHC) showed a 36% reduction in mass. Muscle mass is determined by the balance between protein synthesis and proteolysis; thus, the aim of this work was to evaluate the components involved in these processes. Compared with the muscle from C rats, the EDL muscle from LPHC diet-fed rats showed a reduction (34%) in the in vitro basal protein synthesis and a 22% reduction in the in vitro basal proteolysis suggesting that the reduction in the mass can be associated with a change in the rate of the two processes. Soon after euthanasia, in the EDL muscles of the rats fed the LPHC diet for 15days, the activity of caspase-3 and that of components of the ubiquitin-proteasome system (atrogin-1 content and chymotrypsin-like activity) were decreased. The phosphorylation of p70(S6K) and 4E-BP1, proteins involved in protein synthesis, was also decreased. We observed an increase in the insulin-stimulated protein content of p-Akt. Thus, the higher insulin sensitivity in the EDL muscle of LPHC rats seemed to contribute to the lower proteolysis in LPHC rats. However, even with the higher insulin sensitivity, the reduction in p-E4-BP1 and p70(S6K) indicates a reduction in protein synthesis, showing that factors other than insulin can have a greater effect on the control of protein synthesis. Copyright © 2016 Elsevier Inc. All rights reserved.

  7. FED pumped limiter configuration issues

    International Nuclear Information System (INIS)

    Haines, J.R.; Fuller, G.M.

    1983-01-01

    Impurity control in the Fusion Engineering Device (FED) is provided by a toroidal belt pumped limiter. Limiter design issues addressed in this paper are (1) poloidal location of the limiter belt, (2) shape of the limiter surface facing the plasma, and (3) whether the belt is pumped from one or both sides. The criteria used for evaluation of limiter configuration features were sensitivity to plasma-edge conditions and ease of maintenance and fabrication. The evaluation resulted in the selection of a baseline FED limiter that is located at the bottom of the device and has a flat surface with a single leading edge

  8. FED pumped limiter configuration issues

    International Nuclear Information System (INIS)

    Haines, J.R.; Fuller, G.M.

    1983-01-01

    Impurity control in the Fusion Engineering Device (FED) is provided by a toroidal belt pumped limiter. Limiter design issues addressed in this paper are (1) poloidal location of the limiter belt, (2) shape of the limiter surface facing the plasma, and (3) whether the belt is pumped from one or both sides. The criteria used for evaluation of limiter configuration features were sensitivity to plasma edge conditions and ease of maintenance and fabrication. The evaluation resulted in the selection of a baseline FED limiter that is located at the bottom of the device and has a flat surface with a single leading edge

  9. ADDITION POLYUNSATURATED FATTY ACIDS IN THE DIET INCREASES THE NUMBER AND SIZE OF FOLLICLES IN COWS FED UNDER TROPICAL GRAZING SYSTEM

    Directory of Open Access Journals (Sweden)

    G. Cansino-Arroyo

    2014-08-01

    Full Text Available The objective was determined the effect of polyunsaturated fatty acids (PUFAS on the number and follicular size in cows fed under tropical grazing during the dry season and rainy season. Using a group of cows PUFAS (GA, dry: n=9 and rain: n=13 maintained under grazing continuo, which received a nutritional supplement, with the addition of 5 % of PUFAS in the supplement. A second control group (GT; dry: n=13 and rain: n=9, kept in the same conditions as the previous group, without PUFAS. The number of follicles was greater during the rainy season than during dry (P=0.0001. Cows GT nutritional supplement did not improve the number of follicles between 2 times (P ≥ 0.7. However, the addition of PUFAS to supplement increases the number of follicles during the rainy season (P=0.002. Otherwise, when the cows were ovulation hormonally stimulated are not noted an increase in the number of follicles in cows with or without PUFAS in the supplement. With these results, we can conclude that the number of follicles is affected by perceived conditions, besides that addition of PUFAS increases the number of follicles during the rainy season in tropical grazing cows.

  10. Bioelectrochemical recovery of waste-derived volatile fatty acids and production of hydrogen and alkali.

    Science.gov (United States)

    Zhang, Yifeng; Angelidaki, Irini

    2015-09-15

    Volatile fatty acids (VFA) are organic compounds of great importance for various industries and environmental processes. Fermentation and anaerobic digestion of organic wastes are promising alternative technologies for VFA production. However, one of the major challenges is development of sustainable downstream technologies for VFA recovery. In this study, an innovative microbial bipolar electrodialysis cell (MBEDC) was developed to meet the challenge of waste-derived VFA recovery, produce hydrogen and alkali, and potentially treat wastewater. The MBEDC was operated in fed-batch mode. At an applied voltage of 1.2 V, a VFA recovery efficiency of 98.3%, H2 of 18.4 mL and alkali production presented as pH of 12.64 were obtained using synthetic fermentation broth. The applied voltage, initial VFA concentrations and composition were affecting the VFA recovery. The energy balance revealed that net energy (5.20-6.86 kWh/kg-VFA recovered) was produced at all the applied voltages (0.8-1.4 V). The coexistence of other anionic species had no negative effect on VFA transportation. The VFA concentration was increased 2.96 times after three consecutive batches. Furthermore, the applicability of MBEDC was successfully verified with digestate. These results demonstrate for the first time the possibility of a new method for waste-derived VFA recovery and valuable products production that uses wastewater as fuel and bacteria as catalyst. Copyright © 2015 Elsevier Ltd. All rights reserved.

  11. Direct electrochemistry of glucose oxidase immobilized on nanostructured gold thin films and its application to bioelectrochemical glucose sensor

    International Nuclear Information System (INIS)

    Qiu Cuicui; Wang Xia; Liu Xueying; Hou Shifeng; Ma Houyi

    2012-01-01

    Highlights: ► Au thin films are formed by electrodeposition and galvanic replacement technology. ► Glucose oxidase is stably immobilized via a simple physical adsorption method. ► The direct electrochemical behavior is obtained on the immobilized glucose oxidase. ► An amperometric sensor of glucose with an excellent sensing capability is achieved. - Abstract: Glucose oxidase (GOx) was stably immobilized via a simple physical adsorption method onto the nanostructured Au thin films fabricated by using electrodeposition and galvanic replacement technology, which provides a facile method to prepare morphology-controllable Au films and also facilitates the preparation and application of enzyme modified electrodes. An obvious advantage of the as-prepared enzyme electrode (denoted as GOx/Au/GCE) is that the nano-Au films provide a favorable microenvironment for GOx and facilitate the electron transfer between the active center of GOx and electrodes. Cyclic voltammetry (CV) results indicate that the immobilized GOx displayed a direct, reversible and surface-confined redox reaction in the phosphate buffer solution. Furthermore, the enzyme modified electrode was used as a glucose bioelectrochemical sensor, exhibiting a linear relationship in the concentration ranges of 2.5–32.5 μmol L −1 and 60–130 μmol L −1 with a detection limit of 0.32 μmol L −1 (S/N = 3) at an applied potential of −0.55 V. Due to the excellent stability, sensitivity and anti-interference ability, the Au thin films are hopeful in the construction of glucose biosensors.

  12. Methane emission in a specific riparian-zone sediment decreased with bioelectrochemical manipulation and corresponded to the microbial community dynamics

    Directory of Open Access Journals (Sweden)

    Elliot S. Friedman

    2016-01-01

    Full Text Available Dissimilatory metal-reducing bacteria are widespread in terrestrial ecosystems, especially in anaerobic soils and sediments. Thermodynamically, dissimilatory metal reduction is more favorable than sulfate reduction and methanogenesis but less favorable than denitrification and aerobic respiration. It is critical to understand the complex relationships, including the absence or presence of terminal electron acceptors, that govern microbial competition and coexistence in anaerobic soils and sediments, because subsurface microbial processes can effect greenhouse gas emissions from soils, possibly resulting in impacts at the global scale. Here, we elucidated the effect of an inexhaustible, ferrous-iron and humic-substance mimicking terminal electron acceptor by deploying potentiostatically poised electrodes in the sediment of a very specific stream riparian zone in Upstate New York state. At two sites within the same stream riparian zone during the course of six weeks in the spring of 2013, we measured CH4 and N2/N2O emissions from soil chambers containing either poised or unpoised electrodes, and we harvested biofilms from the electrodes to quantify microbial community dynamics. At the upstream site, which had a lower vegetation cover and highest soil temperatures, the poised electrodes inhibited CH4 emissions by ~45% (when normalized to remove temporal effects. CH4 emissions were not significantly impacted at the downstream site. N2/N2O emissions were generally low at both sites and were not impacted by poised electrodes. We did not find a direct link between bioelectrochemical treatment and microbial community membership; however, we did find a correspondence between environment/function and microbial community dynamics.

  13. Rational engineering of Geobacter sulfurreducens electron transfer components: a foundation for building improved Geobacter-based bioelectrochemical technologies

    Directory of Open Access Journals (Sweden)

    Joana M Dantas

    2015-07-01

    bioelectrochemical technologies.

  14. Estudio comparativo de cuatro sistemas de propagación de levadura cervecera por lote alimentado Comparative study of four fed-batch propagation systems of beer yeast

    Directory of Open Access Journals (Sweden)

    Hoyos H.

    1998-06-01

    Full Text Available

    Se realizó la propagación por lotes de levadura cervecera y con base en estos resultados se ajustó un modelo matemático. Se llevaron a cabo cuatro fermentaciones con diferentes técnicas de alimentación y se confrontaron los resultados mediante simulación. Las técnicas estudiadas fueron alimentación puntual, alimentación continua-puntual y de alta densidad. La mayor concentración celular y factor de propagación se presentó con el cultivo de alta densidad. La simulación demostró que la alimentación continua o puntual afecta el comportamiento celular, ya sea sobre la velocidad específica y/o el factor estequiométrico Yx/s . Se encontró que la técnica de alta densidad aumenta el factor estequiométrico Yx/s.

    Beer yeast was propagated using batch culture, and a mathematical model was fitted to the resulting data. Intermittent, continuousintermittent, and high-density fed-batch techniques were used. The highest cell yield was found using the high density technique. Simulation also unveiled an effect of the feeding technique on cellular growth rate and yield. The high density technique increased the stoichiometric factor Yx/s.

  15. Characteristics of a water pump system fed on photovoltaic panel connected to a battery group; Caracteristicas de um sistema de bombeamento d'agua alimentado por paineis fotovoltaicos ligado a um banco de baterias

    Energy Technology Data Exchange (ETDEWEB)

    Michels, Roger N.; Gnoato, Estor; Santos, Jose A.A. dos; Oyama, Paulo T.; Pasa, Leandro A.; Fischborn, Marcos; Mayer, Giovano; Halmemann, Maria C. [Universidade Tecnologica Federal do Parana (UTFPR-MD), Medianeira, PR (Brazil)], Emails: gnoatto@utfpr.edu.br, airton@utfpr.edu.br, oyama@utfpr.edu.br, pasa@utfpr.edu.br, fisch@utfpr.edu.br, giovano@utfpr.edu.br, cristhal@fca.unesp.br

    2009-07-01

    The photovoltaic solar energy started to be explored intensively in the 80's when researches related to this technology received great investments because it is a clean, renewable and greatly available energy. To improve the efficiency in this form of electric energy generation it is necessary to know its characteristics in order to reach a coherent sizing and foresee in which equipment they can be installed. This project analyzes the characteristics of a water pump system fed on two batteries connected to two photovoltaic modules, with variation of the geometric height of pressure. With the increase of the geometric height of pressure, occurs the reduction of the voltage (not only in the pump but also in the battery) and of the outflow and the increase of the electric current and power. (author)

  16. Optimal neutral beam heating scenario for FED

    International Nuclear Information System (INIS)

    Hively, L.M.; Houlberg, W.A.; Attenberger, S.E.

    1981-01-01

    Optimal neutral beam heating scenarios are determined for FED based on a 1/one-half/-D transport analysis. Tradeoffs are examined between neutral beam energy, power, and species mix for positive ion systems. A ramped density startup is found to provide the most economical heating. The resulting plasma power requirements are reduced by 10-30% from a constant density startup. For beam energies between 100 and 200 keV, the power needed to heat the plasma does not decrease significantly as beam energy is increased. This is due to reduced ion heating, more power in the fractional energy components, and rising power supply requirements as beam energy increases

  17. Converter fed sub sea motor drives

    Energy Technology Data Exchange (ETDEWEB)

    Raad, R O

    1995-09-01

    Minor offshore gas and oil resources located 20-50 km from existing installations may often be commercially exploited only by use of complete sub sea solutions. This thesis deals with analyses of a sub sea adjustable speed electric motor which is fed by a frequency converter via a long cable (up to 50 km) between the converter and the motor. The author develops a general model for analysing such motor drive systems with the objective of verifying the feasibility of specific applications and of specifying the requirements on the system components. The simulation model is used to identify the critical frequency ranges in which the converter must not generate significant harmonics, to verify the start-up strategy chosen, and to verify the stability with potential disturbances applied to the system. Simulation models are developed for both transient and steady state analyses. They are accurate up to 5 kHz and can incorporate the frequency dependency of the motor and cable parameters. Ideal thyristors and diodes are used. The models are implemented in existing simulation tools. Most of the results relate to a base case with a 670 kW squirrel cage motor fed from a 30 km long cable, but cases with 3 MW rating or with 50 km cable have also been analyzed and found to be feasible. Each specific application must be separately studied. Results of simulation calculations are presented and conclusions given. 53 refs., 124 figs., 23 tabs.

  18. Study on Serum Lipoprotein Profile of Exclusive Breast Fed, Mixed Fed and Formula Fed Preterm Infants

    Directory of Open Access Journals (Sweden)

    Vineet Jaiswal

    2017-10-01

    Full Text Available Introduction: Breast feeding is protective for atherosclerotic cardiovascular disease, obesity, Diabetes Mellitus (DM and hypertension. Serum lipoprotein is principal risk factor for atherosclerosis. There is growing evidence that risk of Coronary Heart Disease (CHD begins to emerge from infancy. Lipoprotein level is affected by different feeding pattern during infancy. Aim: To compare serum lipoprotein profile of exclusively breast fed, mixed fed and formula fed preterm infant. Materials and Methods: A total of two fifty preterm newborn were recruited at birth and divided into three groups. Group A were Exclusively Breast Fed (EBF, Group B were Mixed Fed (MF and Group C were Formula/bovine milk Fed (FF infants. Preterm newborns with severe sepsis, hypoglycemia, Hypoxic Ischemic Encephalopathy (HIE stage II and III, meconium stained amniotic fluid, pathological jaundice, Hyaline Membrane Disease (HMD, less than 28 weeks gestation, with major congenital anomaly and infants born to mothers with DM, gestational diabetes, hypertension, pre-eclampsia, eclampsia or on long term medications were excluded from the study. Lipoprotein profile estimation was done at four weeks and again at 16 weeks of age. Results: At four weeks of age, Total Cholesterol (TC, Triglyceride (TG, Low Density Lipoprotein (LDL and Very Low Density Lipoprotein (VLDL were higher in EBF infants as compared to MF and FF infants. For TC, difference was significant between EBF vs. MF (p<0.001, EBF vs. FF (p<0.001 and MF vs. FF (p=0.005 infants. At 16 weeks also, TC and HDL were higher in EBF infants as compared to MF and FF infants. For TC, this difference was significant between EBF vs. MF (p<0.001 and EBF vs. FF (p<0.001 infants. When infants were followed up to 16 weeks of age, TC and LDL level fell significantly (p<0.001 in EBF and MF group, a significant (p<0.05 rise for TC was seen in FF group. At 16 weeks of age, there was no significant rise in HDL in EBF infants, but

  19. Simulation and Modeling of a Five -Level (NPC Inverter Fed by a Photovoltaic Generator and Integrated in a Hybrid Wind-PV Power System

    Directory of Open Access Journals (Sweden)

    M. Rezki,

    2017-08-01

    Full Text Available A distributed hybrid coordinated wind photovoltaic (PV power system was proposed in this paper. As oil and coal reserves are being depleted whilst at the same time the energy demand is growing, it is important to consider alternative energy generating techniques. Today, the five-level (NPC inverter represents a good alternative for several industrial applications. To take advantage of the five-level inverter topology and the benefits of renewable energy represented by a photovoltaic generator, a new scheme of these controllers is proposed in this work. This paper outlines the design of a hybrid power system consisting of a solar photovoltaic (PV and a wind power system. The system is modeled in Matlab Simulink and tested for various conditions. The model and results are discussed in this paper.

  20. Methane (CH4) and nitrous oxide (N2O) emissions from the system of rice intensification (SRI) under a rain-fed lowland rice ecosystem in Cambodia

    DEFF Research Database (Denmark)

    Ly, Proyuth; Jensen, Lars Stoumann; Bruun, Thilde Bech

    2013-01-01

    ) with the following treatments: control, composted farmyard manure (FYM), mineral fertiliser (MF) and FYM + MF. The results indicated large seasonal variations of CH patterns during the growing season with a peak emission of about 1,300 mg CH m day under both production systems 2 weeks after rice transplanting....... There was large temporal variability of CH fluxes from morning to midday. Emission of NO was below the detection limit in both systems. Under each production system, the highest seasonal emission of CH was under the FYM + MF treatment, namely 282 kg ha under CMP and 213 kg ha under SRI. Total CH emission under...... SRI practices was reduced by 22 % in the FYM treatment, 17 % in the MF treatment and 24 % in the FYM + MF treatment compared to CMP. There was no effect of water management on CH emission in the non-fertilized treatment. Grain yields were not significantly affected by the production system. Thus...

  1. Assessment of potential energy savings following the replacement of gear-motor-driven systems by frequency-converter-fed direct drives; Energiesparpotential bei Ersatz von Getriebemotoren durch FU-Antriebe. Potentialanalyse

    Energy Technology Data Exchange (ETDEWEB)

    Tanner, R.; Riesen, H. J.

    2007-03-15

    This project deals with the energy saving potential that can be achieved by replacing gear motor driven systems by frequency converter fed direct drives. Estimates have shown that due to the high percentage of gear motor installations, which amounts to approximately 10% of all motor driven systems, a significant amount of energy could be saved. However, several barriers impose major restrictions to the broad application of such actions: With the exception of worm gears that reach about 20% of all gear drives, todays' gears already offer a high efficiency of 97-98%. Gear motors are often included in OEM integrated solutions. Many processes require complex adaptations that can complicate replacements or make it even impractical. For low speed or high torque requirements, gear motors may have a dominant advantage concerning the compactness. Our investigations have shown, that in spite of such barriers the replacement of gear motors by direct motors can sum up to a significant amount of energy savings in many cases. Looking at the worm gear systems and the restricted speed and torque ranges that are covered by the direct drives from several suppliers we assume a total saving potential of about 78 GWh per year for Switzerland. (author)

  2. High-intensity interval training has beneficial effects on cardiac remodeling through local renin-angiotensin system modulation in mice fed high-fat or high-fructose diets.

    Science.gov (United States)

    de Oliveira Sá, Guilherme; Dos Santos Neves, Vívian; de Oliveira Fraga, Shyrlei R; Souza-Mello, Vanessa; Barbosa-da-Silva, Sandra

    2017-11-15

    HIIT (high-intensity interval training) has the potential to reduce cardiometabolic risk factors, but the effects on cardiac remodeling and local RAS (renin-angiotensin system) in mice fed high-fat or high-fructose diets still need to be fully addressed. Sixty male C57BL/6 mice (12weeks old) were randomly divided into three groups, control (C), High-fat (HF), or High-fructose diet (HRU) and were monitored for eight weeks before being submitted to the HIIT. Each group was randomly assigned to 2 subgroups, one subgroup was started on a 12-week HIIT protocol (T=trained group), while the other subgroup remained non-exercised (NT=not-trained group). HIIT reduced BM and systolic blood pressure in high-fat groups, while enhanced insulin sensitivity after high-fat or high-fructose intake. Moreover, HIIT reduced left ventricular hypertrophy in HF-T and HFRU-T. Notably, HIIT modulated key factors in the local left ventricular renin-angiotensin-system (RAS): reduced protein expression of renin, ACE (Angiotensin-converting enzyme), and (Angiotensin type 2 receptor) AT2R in HF-T and HFRU-T groups but reduced (Angiotensin type 1 receptor) AT1R protein expression only in the high-fat trained group. HIIT modulated ACE2/Ang (1-7)/Mas receptor axis. ACE2 mRNA gene expression was enhanced in HF-T and HFRU-T groups, complying with elevated Mas (Mas proto-oncogene, G protein-coupled receptor) receptor mRNA gene expression after HIIT. This study shows the effectiveness of HIIT sessions in producing improvements in insulin sensitivity and mitigating LV hypertrophy, though hypertension was controlled only in the high-fat-fed submitted to HIIT protocol. Local RAS system in the heart mediates these findings and receptor MAS seems to play a pivotal role when it comes to the amelioration of cardiac structural and functional remodeling due to HIIT. Copyright © 2017 Elsevier Inc. All rights reserved.

  3. Water-saving analysis on an effective water reuse system in biodiesel feedstock production based on Chlorella zofingiensis fed-batch cultivation.

    Science.gov (United States)

    Yang, Kang; Qin, Lei; Wang, Zhongming; Feng, Wei; Feng, Pingzhong; Zhu, Shunni; Xu, Jingliang; Yuan, Zhenhong

    2015-01-01

    The micralgae-based biofuel obtained from dairy wastewater (DWW) is considered a promising source of energy. However, this process consumes water due to the concentration of wastewater being normally too high for some micoralgae cultivation, and dilution is always needed. In this work, the cultivation of microalgae has been examined in non-recirculated water (NR) and recirculated water systems (R). The growth of Chlorella zofingiensis and the nutrient removal of DWW have been recorded. The comparison indicates the R had a little more advantage in biomass and lipid output (1.55, 0.22 g, respectively) than the NR (1.51, 0.20 g, respectively). However, the total chemical oxygen demand (COD), total Kjeldahl nitrogen (TKN), and total phosphorus (TP) removals of the R were lower than those of the NR system during the culture. The highest removal of total COD, TKN, and TP were 85.05%, 93.64%, and 98.45%, respectively. Furthermore, no significant difference has been observed in the higher heating value and lipid content of the biomass of the R and NR. The results show the R can save 30% of the total water input during the culture. All above results indicate the R system has great potential in industry.

  4. FED baseline engineering studies report

    Energy Technology Data Exchange (ETDEWEB)

    Sager, P.H.

    1983-04-01

    Studies were carried out on the FED Baseline to improve design definition, establish feasibility, and reduce cost. Emphasis was placed on cost reduction, but significant feasibility concerns existed in several areas, and better design definition was required to establish feasibility and provide a better basis for cost estimates. Design definition and feasibility studies included the development of a labyrinth shield ring concept to prevent radiation streaming between the torus spool and the TF coil cryostat. The labyrinth shield concept which was developed reduced radiation streaming sufficiently to permit contact maintenance of the inboard EF coils. Various concepts of preventing arcing between adjacent shield sectors were also explored. It was concluded that installation of copper straps with molybdenum thermal radiation shields would provide the most reliable means of preventing arcing. Other design studies included torus spool electrical/structural concepts, test module shielding, torus seismic response, poloidal conditions in the magnets, disruption characteristics, and eddy current effects. These additional studies had no significant impact on cost but did confirm the feasibility of the basic FED Baseline concept.

  5. FED baseline engineering studies report

    International Nuclear Information System (INIS)

    Sager, P.H.

    1983-04-01

    Studies were carried out on the FED Baseline to improve design definition, establish feasibility, and reduce cost. Emphasis was placed on cost reduction, but significant feasibility concerns existed in several areas, and better design definition was required to establish feasibility and provide a better basis for cost estimates. Design definition and feasibility studies included the development of a labyrinth shield ring concept to prevent radiation streaming between the torus spool and the TF coil cryostat. The labyrinth shield concept which was developed reduced radiation streaming sufficiently to permit contact maintenance of the inboard EF coils. Various concepts of preventing arcing between adjacent shield sectors were also explored. It was concluded that installation of copper straps with molybdenum thermal radiation shields would provide the most reliable means of preventing arcing. Other design studies included torus spool electrical/structural concepts, test module shielding, torus seismic response, poloidal conditions in the magnets, disruption characteristics, and eddy current effects. These additional studies had no significant impact on cost but did confirm the feasibility of the basic FED Baseline concept

  6. Load-Independent Harmonic Mitigation in SCR-Fed Three-Phase Multiple Adjustable Speed Drive Systems with Deliberately Dispatched Firing Angles

    DEFF Research Database (Denmark)

    Yang, Yongheng; Davari, Pooya; Blaabjerg, Frede

    2018-01-01

    Adjustable speed drives (ASD) are widely used in industry for energy savings, where low-cost diode rectifiers are still employed as the front-ends, also for simplicity in control and reliability in operation. However, significant harmonics appear at the grid, which should be tackled according...... a harmonic mitigation strategy for multiple ASD systems, where silicon-controlled rectifiers (SCR) with boost converters in the dc-link have been adopted to increase the harmonic-current controllability. More specific, the SCR firing angles are deliberately dispatched among the drive units, which results...

  7. Citrus flavanones prevent systemic inflammation and ameliorate oxidative stress in C57BL/6J mice fed high-fat diet.

    Science.gov (United States)

    Ferreira, Paula S; Spolidorio, Luis C; Manthey, John A; Cesar, Thais B

    2016-06-15

    The flavanones hesperidin, eriocitrin and eriodictyol were investigated for their prevention of the oxidative stress and systemic inflammation caused by high-fat diet in C57BL/6J mice. The mice received a standard diet (9.5% kcal from fat), high-fat diet (45% kcal from fat) or high-fat diet supplemented with hesperidin, eriocitrin or eriodictyol for a period of four weeks. Hesperidin, eriocitrin and eriodictyol increased the serum total antioxidant capacity, and restrained the elevation of interleukin-6 (IL-6), macrophage chemoattractant protein-1 (MCP-1), and C-reactive protein (hs-CRP). In addition, the liver TBARS levels and spleen mass (g per kg body weight) were lower for the flavanone-treated mice than in the unsupplemented mice. Eriocitrin and eriodictyol reduced TBARS levels in the blood serum, and hesperidin and eriodictyol also reduced fat accumulation and liver damage. The results showed that hesperidin, eriocitrin and eriodictyol had protective effects against inflammation and oxidative stress caused by high-fat diet in mice, and may therefore prevent metabolic alterations associated with the development of cardiovascular diseases in other animals.

  8. Engineering the bioelectrochemical interface using functional nanomaterials and microchip technique toward sensitive and portable electrochemical biosensors.

    Science.gov (United States)

    Jia, Xiaofang; Dong, Shaojun; Wang, Erkang

    2016-02-15

    Electrochemical biosensors have played active roles at the forefront of bioanalysis because they have the potential to achieve sensitive, specific and low-cost detection of biomolecules and many others. Engineering the electrochemical sensing interface with functional nanomaterials leads to novel electrochemical biosensors with improved performances in terms of sensitivity, selectivity, stability and simplicity. Functional nanomaterials possess good conductivity, catalytic activity, biocompatibility and high surface area. Coupled with bio-recognition elements, these features can amplify signal transduction and biorecognition events, resulting in highly sensitive biosensing. Additionally, microfluidic electrochemical biosensors have attracted considerable attention on account of their miniature, portable and low-cost systems as well as high fabrication throughput and ease of scaleup. For example, electrochemical enzymetic biosensors and aptamer biosensors (aptasensors) based on the integrated microchip can be used for portable point-of-care diagnostics and environmental monitoring. This review is a summary of our recent progress in the field of electrochemical biosensors, including aptasensors, cytosensors, enzymatic biosensors and self-powered biosensors based on biofuel cells. We presented the advantages that functional nanomaterials and microfluidic chip technology bring to the electrochemical biosensors, together with future prospects and possible challenges. Copyright © 2015 Elsevier B.V. All rights reserved.

  9. Bioelectrochemical biosensor for water toxicity detection: generation of dual signals for electrochemical assay confirmation.

    Science.gov (United States)

    Yang, Yuan; Wang, Yan-Zhai; Fang, Zhen; Yu, Yang-Yang; Yong, Yang-Chun

    2018-02-01

    Toxicity assessment of water is of great important to the safety of human health and to social security because of more and more toxic compounds that are spilled into the aquatic environment. Therefore, the development of fast and reliable toxicity assessment methods is of great interest and attracts much attention. In this study, by using the electrochemical activity of Shewanella oneidensis MR-1 cells as the toxicity indicator, 3,5-dichlorophenol (DCP) as the model toxic compound, a new biosensor for water toxicity assessment was developed. Strikingly, the presence of DCP in the water significantly inhibited the maximum current output of the S. oneidensis MR-1 in a three-electrode system and also retarded the current evolution by the cells. Under the optimized conditions, the maximum current output of the biosensor was proportional to the concentration of DCP up to 30 mg/L. The half maximal inhibitory concentration of DCP determined by this biosensor is about 14.5 mg/L. Furthermore, simultaneous monitoring of the retarded time (Δt) for current generation allowed the identification of another biosensor signal in response to DCP which could be employed to verify the electrochemical result by dual confirmation. Thus, the present study has provided a reliable and promising approach for water quality assessment and risk warning of water toxicity.

  10. Use of inverse modeling to evaluate CENTURY-predictions for soil carbon sequestration in US rain-fed corn production systems.

    Directory of Open Access Journals (Sweden)

    Hoyoung Kwon

    Full Text Available We evaluated the accuracy and precision of the CENTURY soil organic matter model for predicting soil organic carbon (SOC sequestration under rainfed corn-based cropping systems in the US. This was achieved by inversely modeling long-term SOC data obtained from 10 experimental sites where corn, soybean, or wheat were grown with a range of tillage, fertilization, and organic matter additions. Inverse modeling was accomplished using a surrogate model for CENTURY's SOC dynamics sub-model wherein mass balance and decomposition kinetics equations from CENTURY are coded and solved by using a nonlinear regression routine of a standard statistical software package. With this approach we generated statistics of CENTURY parameters that are associated with the effects of N fertilization and organic amendment on SOC decay, which are not as well quantified as those of tillage, and initial status of SOC. The results showed that the fit between simulated and observed SOC prior to inverse modeling (R2 = 0.41 can be improved to R2 = 0.84 mainly by increasing the rate of SOC decay up to 1.5 fold for the year in which N fertilizer application rates are over 200 kg N ha-1. We also observed positive relationships between C inputs and the rate of SOC decay, indicating that the structure of CENTURY, and therefore model accuracy, could be improved by representing SOC decay as Michaelis-Menten kinetics rather than first-order kinetics. Finally, calibration of initial status of SOC against observed levels allowed us to account for site history, confirming that values should be adjusted to account for soil condition during model initialization. Future research should apply this inverse modeling approach to explore how C input rates and N abundance interact to alter SOC decay rates using C inputs made in various forms over a wider range of rates.

  11. Are agrochemicals present in high fructose corn syrup fed to honey bees (Apis mellifera L.)?

    Science.gov (United States)

    Honey bee colonies are commonly fed high fructose corn syrup (HFCS) as a nectar substitute. Many agrochemicals are applied to corn during cultivation including systemic neonicotinoids. Whether agrochemicals are present in HFCS fed to bees is unknown. Samples from the major manufacturers and distri...

  12. Increased kidney growth in formula-fed versus breast-fed healthy infants

    DEFF Research Database (Denmark)

    Schmidt, Ida M; Damgaard, Ida N; Boisen, Kirsten A

    2004-01-01

    versus breast feeding on kidney growth in a cohort of 631 healthy children examined at birth, and at 3 and 18 months of age. Kidney size was determined by ultrasonography and related to gender, age, body size, and feeding category (fully breast fed, partially breast fed, or fully formula fed at 3 months...

  13. Graphene oxide nanoplatforms to enhance catalytic performance of iron phthalocyanine for oxygen reduction reaction in bioelectrochemical systems

    Science.gov (United States)

    Costa de Oliveira, Maida Aysla; Mecheri, Barbara; D'Epifanio, Alessandra; Placidi, Ernesto; Arciprete, Fabrizio; Valentini, Federica; Perandini, Alessando; Valentini, Veronica; Licoccia, Silvia

    2017-07-01

    We report the development of electrocatalysts based on iron phthalocyanine (FePc) supported on graphene oxide (GO), obtained by electrochemical oxidation of graphite in aqueous solution of LiCl, LiClO4, and NaClO4. Structure, surface chemistry, morphology, and thermal stability of the prepared materials were investigated by Fourier transform infrared spectroscopy (FTIR), Raman spectroscopy, atomic force microscopy (AFM), thermogravimetric analysis (TGA), and X-ray photoelectron spectroscopy (XPS). The catalytic activity toward oxygen reduction reaction (ORR) at neutral pH was evaluated by cyclic voltammetry. The experimental results demonstrate that the oxidation degree of GO supports affects the overall catalytic activity of FePc/GO, due to a modulation effect of the interaction between FePc and the basal plane of GO. On the basis of electrochemical, spectroscopic, and morphological investigations, FePc/GO_LiCl was selected to be assembled at the cathode side of a microbial fuel cell prototype, demonstrating a good electrochemical performance in terms of voltage and power generation.

  14. Development of bioelectrochemical systems using various biogas fermenter effluents as inocula and municipal waste liquor as adapting substrate.

    Science.gov (United States)

    Bakonyi, Péter; Koók, László; Keller, Enikő; Bélafi-Bakó, Katalin; Rózsenberszki, Tamás; Saratale, Ganesh Dattatraya; Nguyen, Dinh Duc; Banu, J Rajesh; Nemestóthy, Nándor

    2018-07-01

    The purpose of this research was to improve microbial fuel cell (MFC) performance - treating landfill-derived waste liquor - by applying effluents of various biogas fermenters as inocula. It turned out that the differences of initial microbial community profiles notably influenced the efficiency of MFCs. In fact, the adaptation time (during 3 weeks of operation) has varied significantly, depending on the source of inoculum and accordingly, the obtainable cumulative energy yields were also greatly affected (65% enhancement in case of municipal wastewater sludge inoculum compared to sugar factory waste sludge inoculum). Hence, it could be concluded that the capacity of MFCs to utilize the complex feedstock was heavily dependent on biological factors such as the origin/history of inoculum, the microbial composition as well as proper acclimation period. Therefore, these parameters should be of primary concerns for adequate process design to efficiently generate electricity with microbial fuel cells. Copyright © 2018 Elsevier Ltd. All rights reserved.

  15. Evolving Microbial Communities in Cellulose-Fed Microbial Fuel Cell

    Directory of Open Access Journals (Sweden)

    Renata Toczyłowska-Mamińska

    2018-01-01

    Full Text Available The abundance of cellulosic wastes make them attractive source of energy for producing electricity in microbial fuel cells (MFCs. However, electricity production from cellulose requires obligate anaerobes that can degrade cellulose and transfer electrons to the electrode (exoelectrogens, and thus most previous MFC studies have been conducted using two-chamber systems to avoid oxygen contamination of the anode. Single-chamber, air-cathode MFCs typically produce higher power densities than aqueous catholyte MFCs and avoid energy input for the cathodic reaction. To better understand the bacterial communities that evolve in single-chamber air-cathode MFCs fed cellulose, we examined the changes in the bacterial consortium in an MFC fed cellulose over time. The most predominant bacteria shown to be capable electron generation was Firmicutes, with the fermenters decomposing cellulose Bacteroidetes. The main genera developed after extended operation of the cellulose-fed MFC were cellulolytic strains, fermenters and electrogens that included: Parabacteroides, Proteiniphilum, Catonella and Clostridium. These results demonstrate that different communities evolve in air-cathode MFCs fed cellulose than the previous two-chamber reactors.

  16. The digestive system of 1-week old Jersey calves is well suited to digest, absorb, and incorporate protein and energy into tissue growth even when fed a high plane of milk replacer.

    Science.gov (United States)

    The objectives of the current study were to determine the digestibilities of nutrients as well as investigate the nitrogen retention of calves fed different planes of milk replacer nutrition during the first week of life. Twelve Jersey calves were blocked by body weight at birth and randomly assigne...

  17. Dietary methionine level affects growth performance and hepatic gene expression of GH-IGF system and protein turnover regulators in rainbow trout (Oncorhynchus mykiss) fed plant protein-based diets

    DEFF Research Database (Denmark)

    Rolland, Marine; Dalsgaard, Anne Johanne Tang; Holm, Jorgen

    2015-01-01

    The effects of dietary level of methionine were investigated in juvenile rainbow trout (Oncorhynchus mykiss) fed five plant-based diets containing increasing content of crystalline methionine (Met), in a six week growth trial. Changes in the hepatic expression of genes related to i...

  18. Liquid-fed ceramic melter: a general description report

    International Nuclear Information System (INIS)

    Buelt, J.L.; Chapman, C.C.

    1978-10-01

    The Pacific Northwest Laboratory is conducting several research and development programs for the solidification of high-level wastes. The liquid-fed ceramic melter (LFCM) is a major component in the solidification process. This melter can solidify liquid high-level waste, as well as melt calcined waste with glass additives and then solidify the mixture. This report describes the LFCM system and shows the main features of the refractories, electrodes and power systems, melter box and lid, draining system, feeding system, and off-gas system

  19. Short communication: Use of a portable, automated, open-circuit gas quantification system and the sulfur hexafluoride tracer technique for measuring enteric methane emissions in Holstein cows fed ad libitum or restricted.

    Science.gov (United States)

    Dorich, C D; Varner, R K; Pereira, A B D; Martineau, R; Soder, K J; Brito, A F

    2015-04-01

    The objective of this study was to measure enteric CH4 emissions using a new portable automated open-circuit gas quantification system (GQS) and the sulfur hexafluoride tracer technique (SF6) in midlactation Holstein cows housed in a tiestall barn. Sixteen cows averaging 176 ± 34 d in milk, 40.7 ± 6.1 kg of milk yield, and 685 ± 49 kg of body weight were randomly assigned to 1 out of 2 treatments according to a crossover design. Treatments were (1) ad libitum (adjusted daily to yield 10% orts) and (2) restricted feed intake [set to restrict feed by 10% of baseline dry matter intake (DMI)]. Each experimental period lasted 22d, with 14 d for treatment adaptation and 8d for data and sample collection. A common diet was fed to the cows as a total mixed ration and contained 40.4% corn silage, 11.2% grass-legume haylage, and 48.4% concentrate on a dry matter basis. Spot 5-min measurements using the GQS were taken twice daily with a 12-h interval between sampling and sampling times advanced 2h daily to account for diurnal variation in CH4 emissions. Canisters for the SF6 method were sampled twice daily before milking with 4 local background gas canisters inside the barn analyzed for background gas concentrations. Enteric CH4 emissions were not affected by treatments and averaged 472 and 458 g/d (standard error of the mean = 18 g/d) for ad libitum and restricted intake treatments, respectively (data not shown). The GQS appears to be a reliable method because of the relatively low coefficients of variation (ranging from 14.1 to 22.4%) for CH4 emissions and a moderate relationship (coefficient of determination = 0.42) between CH4 emissions and DMI. The SF6 resulted in large coefficients of variation (ranging from 16.0 to 111%) for CH4 emissions and a poor relationship (coefficient of determination = 0.17) between CH4 emissions and DMI, likely because of limited barn ventilation and high background gas concentration. Research with improved barn ventilation systems or

  20. Overall control strategy of variable speed doubly-fed induction generator wind turbine

    DEFF Research Database (Denmark)

    Hansen, A.D.; Iov, F.; Sørensen, Poul Ejnar

    2004-01-01

    The variable speed doubly-fed induction generator wind turbine is today the most widely used concept. The paper presents an overall control system of the variable speed DFIG wind turbine, with focus on the control strategies and algorithms applied at each hierarchical control level of the wind tu......-fed induction generator is implemented in the dynamic power system simulation tool DIgSILENT. Simulation results are performed and analyzed in different normal operating conditions....

  1. Sequential nitrification and denitrification in a novel palm shell granular activated carbon twin-chamber upflow bio-electrochemical reactor for treating ammonium-rich wastewater.

    Science.gov (United States)

    Mousavi, Seyyedalireza; Ibrahim, Shaliza; Aroua, Mohamed Kheireddine

    2012-12-01

    In this study, a twin-chamber upflow bio-electrochemical reactor packed with palm shell granular activated carbon as biocarrier and third electrode was used for sequential nitrification and denitrification of nitrogen-rich wastewater under different operating conditions. The experiments were performed at a constant pH value for the denitrification compartment. The effect of variables, namely, electric current (I) and hydraulic retention time (HRT), on the pH was considered in the nitrification chamber. The response surface methodology was used based on three levels to develop empirical models for the study on the effects of HRT and current values as independent operating variables on NH(4)(+)-N removal. The results showed that ammonium was reduced within the function of an extensive operational range of electric intensity (20-50 mA) and HRT (6-24h). The optimum condition for ammonium oxidation (90%) was determined with an I of 32 mA and HRT of 19.2h. Copyright © 2012 Elsevier Ltd. All rights reserved.

  2. Vapor-fed bio-hybrid fuel cell.

    Science.gov (United States)

    Benyamin, Marcus S; Jahnke, Justin P; Mackie, David M

    2017-01-01

    Concentration and purification of ethanol and other biofuels from fermentations are energy-intensive processes, with amplified costs at smaller scales. To circumvent the need for these processes, and to potentially reduce transportation costs as well, we have previously investigated bio-hybrid fuel cells (FCs), in which a fermentation and FC are closely coupled. However, long-term operation requires strictly preventing the fermentation and FC from harming each other. We introduce here the concept of the vapor-fed bio-hybrid FC as a means of continuously extracting power from ongoing fermentations at ambient conditions. By bubbling a carrier gas (N 2 ) through a yeast fermentation and then through a direct ethanol FC, we protect the FC anode from the catalyst poisons in the fermentation (which are non-volatile), and also protect the yeast from harmful FC products (notably acetic acid) and from build-up of ethanol. Since vapor-fed direct ethanol FCs at ambient conditions have never been systematically characterized (in contrast to vapor-fed direct methanol FCs), we first assess the effects on output power and conversion efficiency of ethanol concentration, vapor flow rate, and FC voltage. The results fit a continuous stirred-tank reactor model. Over a wide range of ethanol partial pressures (2-8 mmHg), power densities are comparable to those for liquid-fed direct ethanol FCs at the same temperature, with power densities >2 mW/cm 2 obtained. We then demonstrate the continuous operation of a vapor-fed bio-hybrid FC with fermentation for 5 months, with no indication of performance degradation due to poisoning (of either the FC or the fermentation). It is further shown that the system is stable, recovering quickly from disturbances or from interruptions in maintenance. The vapor-fed bio-hybrid FC enables extraction of power from dilute bio-ethanol streams without costly concentration and purification steps. The concept should be scalable to both large and small

  3. Oral microbial profile discriminates breast-fed from formula-fed infants.

    Science.gov (United States)

    Holgerson, Pernilla L; Vestman, Nelly R; Claesson, Rolf; Ohman, Carina; Domellöf, Magnus; Tanner, Anne C R; Hernell, Olle; Johansson, Ingegerd

    2013-02-01

    Little is known about the effect of diet on the oral microbiota of infants, although diet is known to affect the gut microbiota. The aims of the present study were to compare the oral microbiota in breast-fed and formula-fed infants, and investigate growth inhibition of streptococci by infant-isolated lactobacilli. A total of 207 mothers consented to participation of their 3-month-old infants. A total of 146 (70.5%) infants were exclusively and 38 (18.4%) partially breast-fed, and 23 (11.1%) were exclusively formula-fed. Saliva from all of their infants was cultured for Lactobacillus species, with isolate identifications from 21 infants. Lactobacillus isolates were tested for their ability to suppress Streptococcus mutans and S sanguinis. Oral swabs from 73 infants were analysed by the Human Oral Microbe Identification Microarray (HOMIM) and by quantitative polymerase chain reaction for Lactobacillus gasseri. Lactobacilli were cultured from 27.8% of exclusively and partially breast-fed infants, but not from formula-fed infants. The prevalence of 14 HOMIM-detected taxa, and total salivary lactobacilli counts differed by feeding method. Multivariate modelling of HOMIM-detected bacteria and possible confounders clustered samples from breast-fed infants separately from formula-fed infants. The microbiota of breast-fed infants differed based on vaginal or C-section delivery. Isolates of L plantarum, L gasseri, and L vaginalis inhibited growth of the cariogenic S mutans and the commensal S sanguinis: L plantarum >L gasseri >L vaginalis. The microbiota of the mouth differs between 3-month-old breast-fed and formula-fed infants. Possible mechanisms for microbial differences observed include species suppression by lactobacilli indigenous to breast milk.

  4. Voltage Control in Wind Power Plants with Doubly Fed Generators

    DEFF Research Database (Denmark)

    Garcia, Jorge Martinez

    In this work, the process of designing a wind power plant composed of; doubly fed induction generators, a static compensator unit, mechanically switched capacitors and on-load tap changer, for voltage control is shown. The selected control structure is based on a decentralized system, since...... supplied by the doubly fed induction generator wind turbines is overcome by installing a reactive power compensator, i.e. a static compensator unit, which is coordinated with the plant control by a specific dispatcher. This dispatcher is set according to the result of the wind power plant load flow....... To release the operation of the converters during steady-state disturbances, mechanically switched capacitors are installed in the wind power plant, which due to their characteristics, they are appropriate for permanent disturbances compensation. The mechanically switched capacitors are controlled to allow...

  5. Tokamak-FED plasma-engineering assessments

    International Nuclear Information System (INIS)

    Peng, Y.K.M.; Lyon, J.F.; Rutherford, P.H.

    1981-01-01

    A wide range of plasma assumptions and scenarios has been examined for the current US tokamak FED concept, which aims to provide a controlled, long pulse (approx. 100 s) burning plasma with an energy amplification of greater than or equal to 5, a fusion power of 180 MW, and a neutron wall load of greater than or equal to 0.4 MW/m 2 . The results of the assessment suggest that the current FED baseline parameters of R = 5.0 m, B/sub t/ = 3.6 T, a = 1.3 m, b = 2.1 m (D-shape), and I/sub p/ = 5.4 MA are appropriate in reaching the above plasma performance, despite uncertainties in several plasma physics areas, such as confinement scaling, achievable beta, impurity control, etc. To enhance the probability of achieving fusion ignition and to provide some margin against a short fall in our physics projections in FED, a limited operating capability at B/sub t/ = 4.6 T and I/sub p/ = 6.5 MA is incorporated. Various other options and remedies have also been assessed aiming to alleviate the impact of the uncertainties on the FED design concept. These approaches appear promising because they can be studied within the current fusion physics program and may lead to drastically more cost-effective FED concepts

  6. FED-R2: concept and magnet design of a low-cost FED

    International Nuclear Information System (INIS)

    Williams, J.E.C.; Becker, H.; Blackfield, D.; Bobrov, E.; Bromberg, L.; Cohn, D.R.; Diatchenko, N.; LeClaire, R.

    1982-12-01

    High performance resistive magnet technology was used to develop a design for a compact, low cost version of the fusion engineering device FED. We refer to this design as FED-R2, for FED-resistive magnet design 2 to distinguish it from the larger resistive magnet design for FED which uses demountable coils (FED-R1). The main objectives of FED-R2 are: (1) to demonstrate reliable, quasi-steady state (long pulse, high duty factor) operation with Q/sub p/ approx. 5; (2) to demonstrate Q/sub p/ > 5 operation for a limited number of pulses; (3) to provide high neutron flux for irradiation of nuclear test modules with a total area greater tha 20m 2 ; (4) to utilize steady-state RF current drive if this option appears promising. Based upon the costing codes at the Fusion Engineering Design Center and upon TFTR costs, the estimated direct costs of FED-R2 would be on the range 380 to 460M, a factor of about 2 below that of the baseline FED design

  7. Proceedings of FED remote maintenance equipment workshop

    International Nuclear Information System (INIS)

    Sager, P.; Garin, J.; Hager, E.R.; Spampinato, P.T.; Tobias, D.; Young, N.

    1981-11-01

    A workshop was convened in two sessions in January and March 1981, on the remote maintenance equipment for the Fusion Engineering Device (FED). The objectives of the first session were to familiarize the participants with the status of the design of the FED and to develop a remote maintenance equipment list for the FED. The objective of the second session was to have the participants present design concepts for the equipment which had been identified in the first session. The equipment list was developed for general purpose and special purpose equipment. The general purpose equipment was categorized as manipulators and other, while the special purpose equipment was subdivided according to the reactor subsystem it serviced: electrical, magnetic, and nuclear. Both mobile and fixed base manipulators were identified. Handling machines were identified as the major requirement for special purpose equipment

  8. Status of FED/INTOR electromagnetics

    International Nuclear Information System (INIS)

    Murray, J.G.

    1983-02-01

    This report provides a summary of the electromagnetic studies, calculations, and conclusions in the evolution of the base design of FED/INTOR (Fusion Engineering Device/International Tokamak Reactor). The electromagnetic feastures include the startup, control, disruptions, and design of structures. This report provides information concerning the evolution of the electromagnetic studies on FED and the justification for the eddy current design feature. The report shows that a major design feature required is the provision of a low induction and resistive path for toroidal currents to flow in the structures in order to provide self-stabilization and to manage the disruption energy dissipation

  9. Crescimento e estruturas do sistema digestório de larvas de pacu alimentadas com dieta microencapsulada produzida experimentalmente Growth and structure of the digestive system of pacu larvae fed microencapsulated diet produced experimentally

    Directory of Open Access Journals (Sweden)

    Olívia Cristina Camilo Menossi

    2012-01-01

    Full Text Available Foram comparados os efeitos de diferentes dietas e da transição alimentar sobre o desempenho zootécnico e a morfologia do trato digestório de larvas de pacu alimentadas com duas dietas comerciais e uma dieta experimental microencapsulada produzida por gelificação interna. Larvas com quatro dias de vida receberam os seguintes protocolos alimentares: somente náuplios de artêmia em quantidades crescentes (controle positivo; larvas mantidas em jejum (controle negativo; três tipos de alimento formulado durante todo o experimento (dieta experimental microencapsulada, dieta comercial NRD1.2/2.0, Inve, USA, e dieta Poli-Peixe 450F, PoliNutri, Brasil; e três protocolos de transição alimentar com náuplios de artêmia durante os seis primeiros dias, seis dias de coalimentação, e somente as respectivas dietas formuladas após esse período. O experimento foi conduzido por 23 dias em delineamento inteiramente casualizado, com avaliações periódicas do crescimento e do sistema digestório. A taxa de sobrevivência foi determinada ao final do experimento. Os melhores desempenhos de crescimento e sobrevivência, assim como mais acelerada organogênese do sistema digestório, foram verificados entre os animais que receberam alimento vivo. As larvas que passaram pela transição alimentar apresentaram médias intermediárias de crescimento e sobrevivência e não diferiram entre si. Entre os grupos que receberam apenas dieta inerte, somente naquele alimentado com a dieta nacional houve sobrevivência até o final do experimento. Nenhuma das dietas formuladas é adequada para uso como alimento exclusivo para larvas de pacu. Na fase de transição alimentar, a dieta experimental microencapsulada proporciona resultados de sobrevivência e crescimento semelhantes aos obtidos com dietas comerciais.The effects of different diets and dietary transition on the performance and morphology of the digestive tract of pacu larvae fed two commercial formulated

  10. The digestive system of 1-week-old Jersey calves is well suited to digest, absorb, and incorporate protein and energy into tissue growth even when calves are fed a high plane of milk replacer.

    Science.gov (United States)

    Liang, Yu; Carroll, Jeffery A; Ballou, Michael A

    2016-03-01

    The objectives of the current study were to determine the apparent digestibilities of nitrogen, organic matter, ash, and energy as well as investigate the nitrogen retention of calves fed different planes of milk replacer nutrition during the first week of life. Twelve Jersey calves were blocked by body weight at birth and randomly assigned to either a high plane of nutrition (HPN) or low plane of nutrition (LPN) treatment. The HPN calves were offered 19.2g of dry matter/kg of body weight of a 28% all-milk crude protein and 20% fat milk replacer. The LPN calves were fed 11.6g of dry matter/kg of body weight of a 20% all-milk crude protein and 20% fat milk replacer. All calves were given 3 L of pooled colostrum within 1h of birth after which they were assigned to treatments; no starter was offered during the study. Calves were given 1 d to adapt to their treatments and environment, so calves were 30 to 36 h old at the start of data collection. The study was divided into two 72-h periods. Total collection of feces occurred over each 72 h period, and total urine was collected for the last 24h of each period. Peripheral blood samples were collected at the beginning and end of each period and analyzed for plasma glucose and urea nitrogen concentrations. Data are reported as HPN vs. LPN, respectively. Fecal scores were greater for HPN calves during both periods; however, no difference was found in the dry matter percentage of feces (30.9 vs. 31.9 ± 0.06). No differences were found between treatments in either digestible or metabolizable energy efficiencies, which averaged 93.3 and 83.7%, respectively. A treatment × period interaction was found on the percentage of intake nitrogen retained, in which calves fed the HPN had a greater percentage of intake nitrogen retained during period 1 (87.9 vs. 78.4 ± 1.79%), but was not different from calves fed the LPN during period 2 (85.4 vs. 84.9 ± 1.79%). From these data therefore, we conclude that healthy neonatal calves have

  11. FED firmware interface testing with pixel phase 1 emulator

    CERN Document Server

    Kilpatrick, Matthew

    2017-01-01

    A hardware emulation of the CMS pixel detector phase 1 upgrade front-end electronics has been developed to test and validate the architecture of the back-end electronics (FED) firmware. The emulation is implemented on a Virtex 6 FPGA on the CERN GLIB uTCA platform, utilizing an 8-way SFP FPGA Mezzanine Card to drive compatible optical transmitters to the back-end electronics at 400 bps. The firmware emulates the complex functions of the phase 1 pixel readout chips (PSI46digv2 and PROC600) and token bit manager ASICs and allows for possible abnormalities that can occur in the output data stream. The emulation implements both fixed data patterns that are used as test vectors and realistic simulated data to drive the readout of the FED at the expected data and trigger rates. Testing software was developed to control the emulator and verify correct transmission of data and exception handling in the FED. An installation has been integrated into the pixel DAQ test system at CMS to be used for fast validation of F...

  12. FED firmware interface testing with pixel phase 1 emulator

    CERN Document Server

    Kilpatrick, Matthew

    2018-01-01

    A hardware emulation of the CMS pixel detector phase 1 upgrade front-end electronics has been developed to test and validate the architecture of the back-end electronics (FED) firmware. The emulation is implemented on a Virtex 6 FPGA on the CERN GLIB uTCA platform, utilizing an 8-way SFP FPGA Mezzanine Card to drive compatible optical transmitters to the back-end electronics at 400 bps. The firmware emulates the complex functions of the phase 1 pixel readout chips (PSI46digv2 and PROC600) and token bit manager ASICs and allows for possible abnormalities that can occur in the output data stream. The emulation implements both fixed data patterns that are used as test vectors and realistic simulated data to drive the readout of the FED at the expected data and trigger rates. Testing software was developed to control the emulator and verify correct transmission of data and exception handling in the FED. An installation has been integrated into the pixel DAQ test system at CMS to be used for fast validation of F...

  13. Reactor performance in terms of COD and nitrogen removal and bacterial community structure of a three-stage rotating bioelectrochemical contactor

    KAUST Repository

    Sayess, Rassil R.

    2013-02-01

    Integrating microbial fuel cell (MFC) into rotating biological contactor (RBC) creates an opportunity for enhanced removal of COD and nitrogen coupled with energy generation from wastewater. In this study, a three-stage rotating bioelectrochemical contactor (referred to as RBC-MFC unit) integrating MFC with RBC technology was constructed for simultaneous removal of carbonaceous and nitrogenous compounds and electricity generation from a synthetic medium containing acetate and ammonium. The performance of the RBC-MFC unit was compared to a control reactor (referred to as RBC unit) that was operated under the same conditions but without current generation (i.e. open-circuit mode). The effect of hydraulic loading rate (HLR) and COD/N ratio on the performance of the two units was investigated. At low (3.05 gCOD g-1N) and high COD/N ratio (6.64 gCOD g-1N), both units achieved almost similar COD and ammonia-nitrogen removal. However, the RBC-MFC unit achieved significantly higher denitrification and nitrogen removal compared to the RBC unit indicating improved denitrification at the cathode due to current flow. The average voltage under 1000 Ω external resistance ranged between 0.03 and 0.30 V and between 0.02 and 0.21 V for stages 1 and 2 of the RBC-MFC unit. Pyrosequencing analysis of bacterial 16S rRNA gene revealed high bacterial diversity at the anode and cathode of both units. Genera that play a role in nitrification (Nitrospira; Nitrosomonas), denitrification (Comamonas; Thauera) and electricity generation (Geobacter) were identified at the electrodes. Geobacter was only detected on the anode of the RBC-MFC unit. Nitrifiers and denitrifiers were more abundant in the RBC-MFC unit compared to the RBC unit and were largely present on the cathode of both units suggesting that most of the nitrogen removal occurred at the cathode. © 2012 Elsevier Ltd.

  14. Optimization of a bundle divertor for FED

    International Nuclear Information System (INIS)

    Hively, L.M.; Rothe, K.E.; Minkoff, M.

    1982-01-01

    Optimal double-T bundle divertor configurations have been obtained for the Fusion Engineering Device (FED). On-axis ripple is minimized, while satisfying a series of engineering constraints. The ensuing non-linear optimization problem is solved via a sequence of quadratic programming subproblems, using the VMCON algorithm. The resulting divertor designs are substantially improved over previous configurations

  15. Structural-design considerations for the FED 50-kA equilibrium field coils

    International Nuclear Information System (INIS)

    Buchanan, G.; Bennett, J.G.

    1983-01-01

    The structural support system for two equilibrium field coil conductor concepts is considered for the fusion energy design (FED) 8/10T baseline magnetic-fusion system. Both conductor concepts are discussed. Results indicate that regardless of the conductor concept employed, an external support beam/frame structural system is required to equilibrate the accumulative loadings

  16. Comparative Metagenomic Analysis of Electrogenic Microbial Communities in Differentially Inoculated Swine Wastewater-Fed Microbial Fuel Cells

    Directory of Open Access Journals (Sweden)

    Irina V. Khilyas

    2017-01-01

    Full Text Available Bioelectrochemical systems such as microbial fuel cells (MFCs are promising new technologies for efficient removal of organic compounds from industrial wastewaters, including that generated from swine farming. We inoculated two pairs of laboratory-scale MFCs with sludge granules from a beer wastewater-treating anaerobic digester (IGBS or from sludge taken from the bottom of a tank receiving swine wastewater (SS. The SS-inoculated MFC outperformed the IGBS-inoculated MFC with regard to COD and VFA removal and electricity production. Using a metagenomic approach, we describe the microbial diversity of the MFC planktonic and anodic communities derived from the different inocula. Proteobacteria (mostly Deltaproteobacteria became the predominant phylum in both MFC anodic communities with amplification of the electrogenic genus Geobacter being the most pronounced. Eight dominant and three minor species of Geobacter were found in both MFC anodic communities. The anodic communities of the SS-inoculated MFCs had a higher proportion of Clostridium and Bacteroides relative to those of the IGBS-inoculated MFCs, which were enriched with Pelobacter. The archaeal populations of the SS- and IGBS-inoculated MFCs were dominated by Methanosarcina barkeri and Methanothermobacter thermautotrophicus, respectively. Our results show a long-term influence of inoculum type on the performance and microbial community composition of swine wastewater-treating MFCs.

  17. Energy-efficient adjustable speed double inverter-fed woundrotor ...

    African Journals Online (AJOL)

    Energy-efficient adjustable speed double inverter-fed woundrotor induction motor ... at speeds up to double rated without the magnetic flux reducing is presented. ... Keywords: power, double-fed wound-rotor induction motor drive, steel and ...

  18. Research on grid connection control technology of double fed wind generator

    Science.gov (United States)

    Ling, Li

    2017-01-01

    The composition and working principle of variable speed constant frequency doubly fed wind power generation system is discussed in this thesis. On the basis of theoretical analysis and control on the modeling, the doubly fed wind power generation simulation control system is designed based on a TMS320F2407 digital signal processor (DSP), and has done a large amount of experimental research, which mainly include, variable speed constant frequency, constant pressure, Grid connected control experiment. The running results show that the design of simulation control system is reasonable and can meet the need of experimental research.

  19. Engineering testing requirements in FED/INTOR

    International Nuclear Information System (INIS)

    Abdou, M.A.; Nygren, R.E.; Morgan, G.D.; Trachsel, C.A.; Wire, G.; Oppermann, E.; Puigh, R.; Gold, R.E.

    1982-10-01

    The FED/INTOR critical issues activity has addressed three key testing requirements that have the largest impact on the design, operation and cost of FED/INTOR. These are: (1) the total testing time (fluence) during the device lifetime, (2) the minimum number of back-to-back cycles, and (3) the neutron wall load (power density in the first wall/blanket). The testing program activities were structured into three tasks in order to define the benefits, and in some cases, costs and risks of these testing requirements. The three tasks were carried out with wide participation of experts from a number of organizations in the United States. Similar effort was performed by Japan, the European Community and the Soviet Union

  20. Sky Subtraction with Fiber-Fed Spectrograph

    Science.gov (United States)

    Rodrigues, Myriam

    2017-09-01

    "Historically, fiber-fed spectrographs had been deemed inadequate for the observation of faint targets, mainly because of the difficulty to achieve high accuracy on the sky subtraction. The impossibility to sample the sky in the immediate vicinity of the target in fiber instruments has led to a commonly held view that a multi-object fibre spectrograph cannot achieve an accurate sky subtraction under 1% contrary to their slit counterpart. The next generation of multi-objects spectrograph at the VLT (MOONS) and the planed MOS for the E-ELT (MOSAIC) are fiber-fed instruments, and are aimed to observed targets fainter than the sky continuum level. In this talk, I will present the state-of-art on sky subtraction strategies and data reduction algorithm specifically developed for fiber-fed spectrographs. I will also present the main results of an observational campaign to better characterise the sky spatial and temporal variations ( in particular the continuum and faint sky lines)."

  1. Feasibility study of a pressure fed engine for a water recoverable space shuttle booster Volume 2: Technical, phase A effort

    Science.gov (United States)

    1972-01-01

    Design and systems considerations are presented on an engine concept selection for further preliminary design and program evaluation. These data have been prepared from a feasibility study of a pressure-fed engine for the water recoverable space shuttle booster.

  2. Fusion Engineering Device (FED) first wall/shield design

    International Nuclear Information System (INIS)

    Sager, P.H.; Fuller, G.; Cramer, B.; Davisson, J.; Haines, J.; Kirchner, J.

    1981-01-01

    The torus of the Fusion Engineering Device (FED) is comprised of the bulk shield and its associated spool lstructure and support system, the first wall water-cooled panel and armor systems, and the pumped limiter. The bulk shielding is provided by ten shield sectors that are installed in the spool structure in such a way as to permit extraction of the sectors through the openings between adjacent toroidal field coils with a direct radial movement. The first wall armor is installed on the inboard and top interior walls of these sectors, and the water-cooled panels are installed on the outboard interior walls and the pumped limiter in the bottom of the sectors. The overall design of the first wall and shield system is described in this paper

  3. FED-A, an advanced performance FED based on low safety factor and current drive

    International Nuclear Information System (INIS)

    Peng, Y.K.M.; Rutherford, P.H.

    1983-08-01

    The FED-A study aims to quantify the potential improvement in cost-effectiveness of the Fusion Engineering Device (FED) by assuming low safety factor q (less than 2 as opposed to about 3) at the plasma edge and noninductive current drive (as opposed to only inductive current drive). The FED-A performance objectives are set to be : (1) ignition assuming International Tokamak Reactor (INTOR) plamsa confinement scaling, but still achieving a fusion power amplification Q greater than or equal to 5 when the confinement is degraded by a factor of 2; (2) neutron wall loading of about 1 MW/m 2 , with 0.5 MW/m 2 as a conservative lower bound; and (3) more clearly power-reactor-like operations, such as steady state

  4. Lambs Fed Fresh Winter Forage Rape (Brassica napus L.) Emit Less Methane than Those Fed Perennial Ryegrass (Lolium perenne L.), and Possible Mechanisms behind the Difference

    Science.gov (United States)

    Sun, Xuezhao; Henderson, Gemma; Cox, Faith; Molano, German; Harrison, Scott J.; Luo, Dongwen; Janssen, Peter H.; Pacheco, David

    2015-01-01

    The objectives of this study were to examine long-term effects of feeding forage rape (Brassica napus L.) on methane yields (g methane per kg of feed dry matter intake), and to propose mechanisms that may be responsible for lower emissions from lambs fed forage rape compared to perennial ryegrass (Lolium perenne L.). The lambs were fed fresh winter forage rape or ryegrass as their sole diet for 15 weeks. Methane yields were measured using open circuit respiration chambers, and were 22-30% smaller from forage rape than from ryegrass (averages of 13.6 g versus 19.5 g after 7 weeks, and 17.8 g versus 22.9 g after 15 weeks). The difference therefore persisted consistently for at least 3 months. The smaller methane yields from forage rape were not related to nitrate or sulfate in the feed, which might act as alternative electron acceptors, or to the levels of the potential inhibitors glucosinolates and S-methyl L-cysteine sulfoxide. Ruminal microbial communities in forage rape-fed lambs were different from those in ryegrass-fed lambs, with greater proportions of potentially propionate-forming bacteria, and were consistent with less hydrogen and hence less methane being produced during fermentation. The molar proportions of ruminal acetate were smaller and those of propionate were greater in forage rape-fed lambs, consistent with the larger propionate-forming populations and less hydrogen production. Forage rape contained more readily fermentable carbohydrates and less structural carbohydrates than ryegrass, and was more rapidly degraded in the rumen, which might favour this fermentation profile. The ruminal pH was lower in forage rape-fed lambs, which might inhibit methanogenic activity, shifting the rumen fermentation to more propionate and less hydrogen and methane. The significance of these two mechanisms remains to be investigated. The results suggest that forage rape is a potential methane mitigation tool in pastoral-based sheep production systems. PMID:25803688

  5. BioFed: federated query processing over life sciences linked open data.

    Science.gov (United States)

    Hasnain, Ali; Mehmood, Qaiser; Sana E Zainab, Syeda; Saleem, Muhammad; Warren, Claude; Zehra, Durre; Decker, Stefan; Rebholz-Schuhmann, Dietrich

    2017-03-15

    Biomedical data, e.g. from knowledge bases and ontologies, is increasingly made available following open linked data principles, at best as RDF triple data. This is a necessary step towards unified access to biological data sets, but this still requires solutions to query multiple endpoints for their heterogeneous data to eventually retrieve all the meaningful information. Suggested solutions are based on query federation approaches, which require the submission of SPARQL queries to endpoints. Due to the size and complexity of available data, these solutions have to be optimised for efficient retrieval times and for users in life sciences research. Last but not least, over time, the reliability of data resources in terms of access and quality have to be monitored. Our solution (BioFed) federates data over 130 SPARQL endpoints in life sciences and tailors query submission according to the provenance information. BioFed has been evaluated against the state of the art solution FedX and forms an important benchmark for the life science domain. The efficient cataloguing approach of the federated query processing system 'BioFed', the triple pattern wise source selection and the semantic source normalisation forms the core to our solution. It gathers and integrates data from newly identified public endpoints for federated access. Basic provenance information is linked to the retrieved data. Last but not least, BioFed makes use of the latest SPARQL standard (i.e., 1.1) to leverage the full benefits for query federation. The evaluation is based on 10 simple and 10 complex queries, which address data in 10 major and very popular data sources (e.g., Dugbank, Sider). BioFed is a solution for a single-point-of-access for a large number of SPARQL endpoints providing life science data. It facilitates efficient query generation for data access and provides basic provenance information in combination with the retrieved data. BioFed fully supports SPARQL 1.1 and gives access to the

  6. Performance of a lab-scale bio-electrochemical assisted septic tank for the anaerobic treatment of black water

    OpenAIRE

    Zamalloa Nalvarte, Carlos Enrique; Arends, Jan; Boon, Nico; Verstraete, Willy

    2013-01-01

    Septic tanks are used for the removal of organic particulates in wastewaters by physical accumulation instead of through the biological production of biogas. Improved biogas production in septic tanks is crucial to increase the potential of this system for both energy generation and organic matter removal. In this study, the effect on the biogas production and biogas quality of coupling a 20 L lab-scale septic tank with a microbial electrolysis cell (MEC) was investigated and compared with a ...

  7. Supervision of Fed-Batch Fermentations

    DEFF Research Database (Denmark)

    Gregersen, Lars; Jørgensen, Sten Bay

    1999-01-01

    Process faults may be detected on-line using existing measurements based upon modelling that is entirely data driven. A multivariate statistical model is developed and used for fault diagnosis of an industrial fed-batch fermentation process. Data from several (25) batches are used to develop...... a model for cultivation behaviour. This model is validated against 13 data sets and demonstrated to explain a significant amount of variation in the data. The multivariate model may directly be used for process monitoring. With this method faults are detected in real time and the responsible measurements...

  8. Exocrine pancreatic secretion is stimulated in piglets fed Fish oil compared with those fed Coconut Oil or Lard

    DEFF Research Database (Denmark)

    Hedemann, Mette Skou; Pedersen, Asger Roer; Engberg, Ricarda M.

    2001-01-01

    An experiment was conducted to study the effect of feeding diets containing fat sources with different fatty acid composition (fish oil, coconut oil or lard, 10 g/100 g diet) on exocrine pancreatic secretion in piglets after weaning. A total of 16 barrows were weaned at 4 wk of age; 3 d later...... the coconut oil or lard diets. The output [U/(h. kg(0.75))] of lipase was higher in piglets fed fish oil than in piglets fed lard or coconut oil. The output of colipase was greater in piglets fed fish oil and coconut oil than in those fed lard. The dietary treatments did not affect the output of carboxylester...... hydrolase. The output of trypsin was significantly lower in piglets fed lard than in piglets fed fish oil or coconut oil diets and the output of carboxypeptidase B was greater in those fed the fish oil diet. Protein, chymotrypsin, carboxypeptidase A, elastase and amylase outputs did not differ among...

  9. A New Asymmetrical Current-fed Converter with Voltage Lifting

    Directory of Open Access Journals (Sweden)

    DELSHAD, M.

    2011-05-01

    Full Text Available This paper presents a new zero voltage switching current-fed DC-DC converter with high voltage gain. In this converter all switches (main and auxiliary turn on under zero voltage switching and turn off under almost zero voltage switching due to snubber capacitor. Furthermore, the voltage spike across the main switch due to leakage inductance of forward transformer is absorbed. The flyback transformer which is connected to the output in series causes to high voltage gain and less voltage stress on the power devices. Considering high efficiency and voltage gain of this converter, it is suitable for green generated systems such as fuel cells or photovoltaic systems. The presented experimental results verify the integrity of the proposed converter.

  10. Time-dependent bacterial community and electrochemical characterizations of cathodic biofilms in the surfactant-amended sediment-based bioelectrochemical reactor with enhanced 2,3,4,5-tetrachlorobiphenyl dechlorination.

    Science.gov (United States)

    Wan, Hui; Yi, Xiaoyun; Liu, Xiaoping; Feng, Chunhua; Dang, Zhi; Wei, Chaohai

    2018-05-01

    Applying an electric field to stimulate the microbial reductive dechlorination of polychlorinated biphenyls (PCBs) represents a promising approach for bioremediation of PCB-contaminated sites. This study aimed to demonstrate the biocathodic film-facilitated reduction of PCB 61 in a sediment-based bioelectrochemical reactor (BER) and, more importantly, the characterizations of electrode-microbe interaction from microbial and electrochemical perspectives particularly in a time-dependent manner. The application of a cathodic potential (-0.45 V vs. SHE) significantly improved the rate and extent of PCB 61 dechlorination compared to the open-circuit scenario (without electrical stimulation), and the addition of an external surfactant further increased the dechlorination, with Tween 80 exerting more pronounced effects than rhamnolipid. The bacterial composition of the biofilms and the bioelectrochemical kinetics of the BERs were found to be time-dependent and to vary considerably with the incubation time and slightly with the coexistence of an external surfactant. Excellent correlations were observed between the dechlorination rate and the relative abundance of Dehalogenimonas, Dechloromonas, and Geobacter, the dechlorination rate and the cathodic current density recorded from the chronoamperometry tests, and the dechlorination rate and the charge transfer resistance derived from the electrochemical impedance tests, with respect to the 120 day-operation. After day 120, PCB 61 was resistant to further appreciable reduction, but substantial hydrogen production was detected, and the bacterial community and electrochemical parameters observed on day 180 were not distinctly different from those on day 120. Copyright © 2018 Elsevier Ltd. All rights reserved.

  11. Bio-electrochemical microelectrode arrays for glutamate and electrophysiology detection in hippocampus of temporal lobe epileptic rats.

    Science.gov (United States)

    Li, Ziyue; Song, Yilin; Xiao, Guihua; Gao, Fei; Xu, Shengwei; Wang, Mixia; Zhang, Yu; Guo, Fengru; Liu, Jie; Xia, Yang; Cai, Xinxia

    2018-06-01

    Temporal Lobe Epilepsy (TLE) is a chronic neurological disorder, characterized by sudden, repeated and transient central nervous system dysfunction. For better understanding of TLE, bio-nanomodified microelectrode arrays (MEA) are designed, for the achievement of high-quality simultaneous detection of glutamate signals (Glu) and multi-channel electrophysiological signals including action potentials (spikes) and local field potentials (LFPs). The MEA was fabricated by Micro-Electro-Mechanical System fabrication technology and all recording sites were modified with platinum black nano-particles, the average impedance decreased by nearly 90 times. Additionally, glutamate oxidase was also modified for the detection of Glu. The average sensitivity of the electrode in Glu solution was 1.999 ± 0.032 × 10 -2 pA/μM·μm 2 (n = 3) and linearity was R = 0.9986, with a good selectivity of 97.82% for glutamate and effective blocking of other interferents. In the in-vivo experiments, the MEA was subjected in hippocampus to electrophysiology and Glu concentration detection. During seizures, the fire rate of spikes increases, and the interspike interval is concentrated within 30 ms. The amplitude of LFPs increases by 3 times and the power increases. The Glu level (4.22 μM, n = 4) was obviously higher than normal rats (2.24 μM, n = 4). The MEA probe provides an advanced tool for the detection of dual-mode signals in the research of neurological diseases. Copyright © 2018 Elsevier Inc. All rights reserved.

  12. Thickness-Dependent Bioelectrochemical and Energy Applications of Thickness-Controlled Meso-Macroporous Antimony-Doped Tin Oxide

    Directory of Open Access Journals (Sweden)

    Daniel Mieritz

    2018-04-01

    Full Text Available Coatings of hierarchically meso-macroporous antimony-doped tin oxide (ATO enable interfacing adsorbed species, such as biomacromolecules, with an electronic circuit. The coating thickness is a limiting factor for the surface coverage of adsorbates, that are electrochemically addressable. To overcome this challenge, a carbon black-based templating method was developed by studying the composition of the template system, and finding the right conditions for self-standing templates, preventing the reaction mixture from flowing out of the mask. The thicknesses of as-fabricated coatings were measured using stylus profilometry to establish a relationship between the mask thickness and the coating thickness. Cyclic voltammetry was performed on coatings with adsorbed cytochrome c to check whether the entire coating thickness was electrochemically addressable. Further, bacterial photosynthetic reaction centers were incorporated into the coatings, and photocurrent with respect to coating thickness was studied. The template mixture required enough of both carbon black and polymer, roughly 7% carbon black and 6% poly(ethylene glycol. Coatings were fabricated with thicknesses approaching 30 µm, and thickness was shown to be controllable up to at least 15 µm. Under the experimental conditions, photocurrent was found to increase linearly with the coating thickness, up to around 12 µm, above which were diminished gains.

  13. Performance of a lab-scale bio-electrochemical assisted septic tank for the anaerobic treatment of black water.

    Science.gov (United States)

    Zamalloa, Carlos; Arends, Jan B A; Boon, Nico; Verstraete, Willy

    2013-06-25

    Septic tanks are used for the removal of organic particulates in wastewaters by physical accumulation instead of through the biological production of biogas. Improved biogas production in septic tanks is crucial to increase the potential of this system for both energy generation and organic matter removal. In this study, the effect on the biogas production and biogas quality of coupling a 20 L lab-scale septic tank with a microbial electrolysis cell (MEC) was investigated and compared with a standard septic tank. Both reactors were operated at a volumetric organic loading rate of 0.5gCOD/Ld and a hydraulic retention time between 20 and 40 days using black water as an input under mesophilic conditions for a period of 3 months. The MEC-septic tank was operated at an applied voltage of 2.0±0.1V and the current experienced ranged from 40 mA (0.9A/m(2) projected electrode area) to 180 mA (5A/m(2) projected electrode area). The COD removal was of the order of 85% and the concentration of residual COD was not different between both reactors. Yet, the total phosphorous in the output was on average 39% lower in the MEC-septic tank. Moreover, the biogas production rate in the MEC-septic tank was a factor of 5 higher than in the control reactor and the H2S concentration in the biogas was a factor of 2.5 lower. The extra electricity supplied to the MEC-septic tank was recovered as extra biogas produced. Overall, it appears that the combination of MEC and a septic tank offers perspectives in terms of lower discharge of phosphorus and H2S, nutrient recuperation and a more reliable supply of biogas. Copyright © 2013 Elsevier B.V. All rights reserved.

  14. Comammox Nitrospira are key nitrifiers in diverse groundwater-fed drinking water filters

    DEFF Research Database (Denmark)

    Fowler, Jane; Palomo, Alejandro; Smets, Barth F.

    Nitrification is a dominant process in groundwater-fed rapid sand filters (RSFs) used for drinking water purification. Near complete removal of ammonium and nitrite is required in the EU and Denmark due to strict regulatory limits that enable high water stability in the distribution system. RSFs...... this work provides a new assay for the simultaneous detection of clade A and B comammox Nitrospira and expands our current knowledge of the diversity of comammox Nitrospira, while attempting to explain the success of comammox Nitrospira in these groundwater-fed filters....

  15. The growth of juvenile jaguar guapote (Cichlasoma managuense fed diets with different carbohydrate levels (ESP

    Directory of Open Access Journals (Sweden)

    Juan B Ulloa R.

    2016-03-01

    Full Text Available The experiment was conducted in a 16 45 L aquaria recirculation system. The objective was to evaluate the growth of jaguar guapote (Cichlasoma managuense when fed isocaloric diets with increasing carbohydrate levels from 11 to 36 percent. Relative metabolic growth rate and feed conversion were similar with diets containing 11.5%, 18.8% and 26.5% carbohydrate (P > 0.05 . The highest protein efficiency ratio (PER and apparent net protein utilization (NPUa values were found with the 18.8% carbohydrate diet. Growth performance, feed utilization parameters and the survival were the lowest with fish fed the highest carbohydrate level (35.6%. Fish body protein increased and body fat decreased with increasing dietary carbohydrate levels. The body ash showed a trend similar to the body protein. It is concluded that juvenile C. managuense can grow well when fed 40% protein diets containing up to 26.5% carbohydrate.

  16. Enteric methane production and ruminal fermentation from forage brassica diets fed in continuous culture

    Science.gov (United States)

    Brassicas provide forage for livestock during the late fall when traditional perennial cool-season forages are not productive. However, little research exists on ruminal fermentation and methane(CH4) production of brassicas fed as forage. A continuous culture fermentor system was used to assess nutr...

  17. Vagal afferents are essential for maximal resection-induced intestinal adaptive growth in orally fed rats

    DEFF Research Database (Denmark)

    Nelson, David W; Liu, Xiaowen; Holst, Jens Juul

    2006-01-01

    in mucosal mass, protein, DNA, and histology. Both systemic and perivagal capsaicin significantly attenuated by 48-100% resection-induced increases in ileal mucosal mass, protein, and DNA in rats fed orally. Villus height was significantly reduced in resected rats given capsaicin compared with vehicle...

  18. Analysis of historical rainfall data and associated risks on rain-fed tef ...

    African Journals Online (AJOL)

    The central theme for this paper is studying the rainfall behavior over the past six decades in relation to the major rainfall induced risks for the rain-fed “tef” production system using 59 years of rainfall data. Risk of dry spell during germination and flowering is computed whereas crop water requirement satisfaction index is ...

  19. Nitrogen, phosphorus and carbon excretion and losses in growing pigs fed Danish or Asian diets

    DEFF Research Database (Denmark)

    Prapaspongsa, Trakarn; Vu, Van Thi Khanh; Poulsen, Hanne Damgaard

    2008-01-01

    The objectives of this study were to determine inputs and outputs of nitrogen (N), phosphorus (P) and carbon (C) and to estimate the nutrient losses during housing and storage in order to address these important parts of the whole manure management systems in pigs fed different diets....

  20. High Order Sliding Mode Control of Doubly-fed Induction Generator under Unbalanced Grid Faults

    DEFF Research Database (Denmark)

    Zhu, Rongwu; Chen, Zhe; Wu, Xiaojie

    2013-01-01

    This paper deals with a doubly-fed induction generator-based (DFIG) wind turbine system under grid fault conditions such as: unbalanced grid voltage, three-phase grid fault, using a high order sliding mode control (SMC). A second order sliding mode controller, which is robust with respect...

  1. Operating Regions of Adjustable-Speed Units with Doubly Fed Machines

    Czech Academy of Sciences Publication Activity Database

    Schreier, Luděk; Chomát, Miroslav; Bendl, Jiří

    2004-01-01

    Roč. 49, č. 2 (2004), s. 119-136 ISSN 0001-7043 R&D Projects: GA AV ČR IAA2057102 Keywords : AC machines * adjustable-speed systems * doubly fed machine Subject RIV: JA - Electronics ; Optoelectronics, Electrical Engineering

  2. L-strip proximity fed ga

    Directory of Open Access Journals (Sweden)

    Ashish Singh

    2014-03-01

    Full Text Available In this article, the analysis of dualband L-strip fed compact semi-circular disk microstrip patch antenna has been presented using circuit theory concept. The antenna parameters such as return loss, VSWR and radiation pattern are calculated. The effect of geometric dimensions of the proposed antenna such as length of vertical and horizontal portion of L-strip is investigated. It is found that antenna resonate at two distinct modes i.e. 1.3 GHz and 6.13 GHz for lower and upper resonance frequencies respectively. The bandwidth of the proposed antenna at lower resonance frequency is 6.61% (simulated and 10.64% (theoretical whereas at upper resonance frequency, it is 6.02% (simulated and 9.06 % (theoretical. The theoretical results are compared with IE3D simulation results as well as experimental results and they are in close agreement.

  3. Robust Adaptive Reactive Power Control for Doubly Fed Induction Generator

    Directory of Open Access Journals (Sweden)

    Huabin Wen

    2014-01-01

    Full Text Available The problem of reactive power control for mains-side inverter (MSI in doubly fed induction generator (DFIG is studied in this paper. To accommodate the modelling nonlinearities and inherent uncertainties, a novel robust adaptive control algorithm for MSI is proposed by utilizing Lyapunov theory that ensures asymptotic stability of the system under unpredictable external disturbances and significant parametric uncertainties. The distinguishing benefit of the aforementioned scheme consists in its capabilities to maintain satisfactory performance under varying operation conditions without the need for manually redesigning or reprogramming the control gains in contrast to the commonly used PI/PID control. Simulations are also built to confirm the correctness and benefits of the control scheme.

  4. Neural network based PWM AC chopper fed induction motor drive

    Directory of Open Access Journals (Sweden)

    Venkatesan Jamuna

    2009-01-01

    Full Text Available In this paper, a new Simulink model for a neural network controlled PWM AC chopper fed single phase induction motor is proposed. Closed loop speed control is achieved using a neural network controller. To maintain a constant fluid flow with a variation in pressure head, drives like fan and pump are operated with closed loop speed control. The need to improve the quality and reliability of the drive circuit has increased because of the growing demand for improving the performance of motor drives. With the increased availability of MOSFET's and IGBT's, PWM converters can be used efficiently in low and medium power applications. From the simulation studies, it is seen that the PWM AC chopper has a better harmonic spectrum and lesser copper loss than the Phase controlled AC chopper. It is observed that the drive system with the proposed model produces better dynamic performance, reduced overshoot and fast transient response. .

  5. LFCM [liquid-fed ceramic melter] vitrification technology: Quarterly progress report, January--March 1987

    International Nuclear Information System (INIS)

    Brouns, R. A.; Allen, C. R.; Powell, J. A.

    1988-05-01

    This report is compiled by the Nuclear Waste Treatment Program and the Hanford Waste Vitrification Program at Pacific Northwest Laboratory to describe the progress in developing, testing, applying and documenting liquid-fed ceramic melter vitrification technology. Progress in the following technical subject areas during the second quarter of FY 1987 is discussed: melting process chemistry and glass development, feed preparation and transfer systems, melter systems, canister filling and handling systems, and process/product modeling. 23 refs., 14 figs., 10 tabs

  6. TopFed: TCGA tailored federated query processing and linking to LOD.

    Science.gov (United States)

    Saleem, Muhammad; Padmanabhuni, Shanmukha S; Ngomo, Axel-Cyrille Ngonga; Iqbal, Aftab; Almeida, Jonas S; Decker, Stefan; Deus, Helena F

    2014-01-01

    The Cancer Genome Atlas (TCGA) is a multidisciplinary, multi-institutional effort to catalogue genetic mutations responsible for cancer using genome analysis techniques. One of the aims of this project is to create a comprehensive and open repository of cancer related molecular analysis, to be exploited by bioinformaticians towards advancing cancer knowledge. However, devising bioinformatics applications to analyse such large dataset is still challenging, as it often requires downloading large archives and parsing the relevant text files. Therefore, it is making it difficult to enable virtual data integration in order to collect the critical co-variates necessary for analysis. We address these issues by transforming the TCGA data into the Semantic Web standard Resource Description Format (RDF), link it to relevant datasets in the Linked Open Data (LOD) cloud and further propose an efficient data distribution strategy to host the resulting 20.4 billion triples data via several SPARQL endpoints. Having the TCGA data distributed across multiple SPARQL endpoints, we enable biomedical scientists to query and retrieve information from these SPARQL endpoints by proposing a TCGA tailored federated SPARQL query processing engine named TopFed. We compare TopFed with a well established federation engine FedX in terms of source selection and query execution time by using 10 different federated SPARQL queries with varying requirements. Our evaluation results show that TopFed selects on average less than half of the sources (with 100% recall) with query execution time equal to one third to that of FedX. With TopFed, we aim to offer biomedical scientists a single-point-of-access through which distributed TCGA data can be accessed in unison. We believe the proposed system can greatly help researchers in the biomedical domain to carry out their research effectively with TCGA as the amount and diversity of data exceeds the ability of local resources to handle its retrieval and

  7. Fed-batch and perfusion culture processes: economic, environmental, and operational feasibility under uncertainty.

    Science.gov (United States)

    Pollock, James; Ho, Sa V; Farid, Suzanne S

    2013-01-01

    This article evaluates the current and future potential of batch and continuous cell culture technologies via a case study based on the commercial manufacture of monoclonal antibodies. The case study compares fed-batch culture to two perfusion technologies: spin-filter perfusion and an emerging perfusion technology utilizing alternating tangential flow (ATF) perfusion. The operational, economic, and environmental feasibility of whole bioprocesses based on these systems was evaluated using a prototype dynamic decision-support tool built at UCL encompassing process economics, discrete-event simulation and uncertainty analysis, and combined with a multi-attribute decision-making technique so as to enable a holistic assessment. The strategies were compared across a range of scales and titres so as to visualize how their ranking changes in different industry scenarios. The deterministic analysis indicated that the ATF perfusion strategy has the potential to offer cost of goods savings of 20% when compared to conventional fed-batch manufacturing processes when a fivefold increase in maximum viable cell densities was assumed. Savings were also seen when the ATF cell density dropped to a threefold increase over the fed-batch strategy for most combinations of titres and production scales. In contrast, the fed-batch strategy performed better in terms of environmental sustainability with a lower water and consumable usage profile. The impact of uncertainty and failure rates on the feasibility of the strategies was explored using Monte Carlo simulation. The risk analysis results demonstrated the enhanced robustness of the fed-batch process but also highlighted that the ATF process was still the most cost-effective option even under uncertainty. The multi-attribute decision-making analysis provided insight into the limited use of spin-filter perfusion strategies in industry. The resulting sensitivity spider plots enabled identification of the critical ratio of weightings of

  8. Growth Performance and Hematological Traits of Weaner Pigs Fed ...

    African Journals Online (AJOL)

    Sixty Weaner pigs with an average initial live weight of 6.81 ± 1.0kg were studied for their growth and haematological parameters when fed graded levels of raw bambara waste (BW) using a completely randomized design (CRD). They were fed five diets containing 0, 25, 50, 75 and 100 percentage composition for 5 months ...

  9. A preliminary study on growth response of broiler finishers fed ...

    African Journals Online (AJOL)

    A preliminary study on growth response of broiler finishers fed processed mottle Mucuna beans ( Mucuna pruriens var. utilis ) ... They were fed diets (20% CP, 13 MJME/kg) incorporating 0%, 5% and 10% processed mottle “Mucuna” beans. A completely randomized design was used. Feed and water were supplied and ...

  10. Synthetic Biology and Microbial Fuel Cells: Towards Self-Sustaining Life Support Systems

    Science.gov (United States)

    Hogan, John Andrew

    2014-01-01

    NASA ARC and the J. Craig Venter Institute (JCVI) collaborated to investigate the development of advanced microbial fuels cells (MFCs) for biological wastewater treatment and electricity production (electrogenesis). Synthetic biology techniques and integrated hardware advances were investigated to increase system efficiency and robustness, with the intent of increasing power self-sufficiency and potential product formation from carbon dioxide. MFCs possess numerous advantages for space missions, including rapid processing, reduced biomass and effective removal of organics, nitrogen and phosphorus. Project efforts include developing space-based MFC concepts, integration analyses, increasing energy efficiency, and investigating novel bioelectrochemical system applications

  11. FET commutated current-FED inverter

    Science.gov (United States)

    Rippel, Wally E. (Inventor); Edwards, Dean B. (Inventor)

    1983-01-01

    A shunt switch comprised of a field-effect transistor (Q.sub.1) is employed to commutate a current-fed inverter (10) using thyristors (SCR1, SCR2) or bijunction transistors (Q.sub.2, Q.sub.3) in a full bridge (1, 2, 3, 4) or half bridge (5, 6) and transformer (T.sub.1) configuration. In the case of thyristors, a tapped inverter (12) is employed to couple the inverter to a dc source to back bias the thyristors during commutation. Alternatively, a commutation power supply (20) may be employed for that purpse. Diodes (D.sub.1, D.sub.2) in series with some voltage dropping element (resistor R.sub.12 or resistors R.sub.1, R.sub.2 or Zener diodes D.sub.4, D.sub.5) are connected in parallel with the thyristors in the half bridge and transformer configuration to assure sharing the back bias voltage. A clamp circuit comprised of a winding (18) negatively coupled to the inductor and a diode (D.sub.3) return stored energy from the inductor to the power supply for efficient operation with buck or boost mode.

  12. Fuzzy Logic-Based Perturb and Observe Algorithm with Variable Step of a Reference Voltage for Solar Permanent Magnet Synchronous Motor Drive System Fed by Direct-Connected Photovoltaic Array

    Directory of Open Access Journals (Sweden)

    Mohamed Redha Rezoug

    2018-02-01

    Full Text Available Photovoltaic pumping is considered to be the most used application amongst other photovoltaic energy applications in isolated sites. This technology is developing with a slow progression to allow the photovoltaic system to operate at its maximum power. This work introduces the modified algorithm which is a perturb and observe (P&O type to overcome the limitations of the conventional P&O algorithm and increase its global performance in abrupt weather condition changes. The most significant conventional P&O algorithm restriction is the difficulty faced when choosing the variable step of the reference voltage value, a good compromise between the swift dynamic response and the stability in the steady state. To adjust the step reference voltage according to the location of the operating point of the maximum power point (MPP, a fuzzy logic controller (FLC block adapted to the P&O algorithm is used. This allows the improvement of the tracking pace and the steady state oscillation elimination. The suggested method was evaluated by simulation using MATLAB/SimPowerSystems blocks and compared to the classical P&O under different irradiation levels. The results obtained show the effectiveness of the technique proposed and its capacity for the practical and efficient tracking of maximum power.

  13. Dietary taurine alters ascorbic acid metabolism in rats fed diets containing polychlorinated biphenyls.

    Science.gov (United States)

    Mochizuki, H; Oda, H; Yokogoshi, H

    2000-04-01

    The effect of dietary taurine on ascorbic acid metabolism and hepatic drug-metabolizing enzymes was investigated in rats fed diets containing polychlorinated biphenyls (PCB) to determine whether taurine has an adaptive and protective function in xenobiotic-treated animals. Young male Wistar rats (60 g) were fed diets containing 0 or 0.2 g/kg diet PCB with or without 30 g/kg diet of taurine for 14 d. The rats fed the PCB-containing diets had greater liver weight, higher ascorbic acid concentrations in the liver and spleen and greater hepatic cytochrome P-450 contents than control rats that were not treated with PCB (P ascorbic acid excretion was enhanced, and serum cholesterol concentration (especially HDL-cholesterol) was significantly elevated compared with those in control rats. Dietary taurine significantly potentiated the increases in the urinary excretion of ascorbic acid and the rise in the levels of cytochrome P-450 which were caused by PCB treatment. On the other hand, the supplementation of taurine to control diet did not alter these variables. Taurine may enhance the hepatic drug-metabolizing systems, leading to the stimulation of the ascorbic acid metabolism in rats fed diets containing PCB.

  14. Efficacy and immunogenicity of live-attenuated human rotavirus vaccine in breast-fed and formula-fed European infants.

    Science.gov (United States)

    Vesikari, Timo; Prymula, Roman; Schuster, Volker; Tejedor, Juan-C; Cohen, Robert; Bouckenooghe, Alain; Damaso, Silvia; Han, Htay Htay

    2012-05-01

    Rotavirus is the main cause of severe gastroenteritis and diarrhea in infants and young children less than 5 years of age. Potential impact of breast-feeding on the efficacy and immunogenicity of human rotavirus G1P[8] vaccine was examined in this exploratory analysis. Healthy infants (N = 3994) aged 6-14 weeks who received 2 doses of human rotavirus vaccine/placebo according to a 0-1 or 0-2 month schedule were followed for rotavirus gastroenteritis during 2 epidemic seasons. Rotavirus IgA seroconversion rate (anti-IgA antibody concentration ≥ 20 mIU/mL) and geometric mean concentrations were measured prevaccination and 1-2 months post-dose 2. Vaccine efficacy against any and severe rotavirus gastroenteritis was analyzed according to the infants being breast-fed or exclusively formula-fed at the time of vaccination. Antirotavirus IgA seroconversion rate was 85.5% (95% confidence interval [CI]: 82.4-88.3) in breast-fed and 89.2% (95% CI: 84.2-93) in exclusively formula-fed infants; geometric mean concentrations in the respective groups were 185.8 U/mL (95% CI: 161.4-213.9) and 231.5 U/mL (95% CI: 185.9-288.2). Vaccine efficacy was equally high in breast-fed and exclusively formula-fed children in the first season but fell in breast-fed infants in the second rotavirus season. During the combined 2-year efficacy follow-up period, vaccine efficacy against any rotavirus gastroenteritis was 76.2% (95% CI: 68.7-82.1) and 89.8% (95% CI: 77.6-95.9) and against severe rotavirus gastroenteritis 88.4% (95% CI: 81.6-93) and 98.1% (95% CI: 88.2-100) in the breast-fed and exclusively formula-fed infants, respectively. The difference in immunogenicity of human rotavirus vaccine in breast-fed and exclusively formula-fed infants was small. Vaccine efficacy was equally high in breast-fed and exclusively formula-fed children in the first season. Breast-feeding seemed to reduce slightly the efficacy in the second season.

  15. Bioavailability of cadmium in rats fed various diets

    International Nuclear Information System (INIS)

    Rabar, I.; Kostial, K.

    1981-01-01

    Six-week-old female albino rats were fed rat diet or human foods 3 days before and 6 days after a single oral dose of 115 sup(m)Cd. All animals were killed 6 days after administration and the radioactivity in the whole body and in the gut-free carcass was determined in a double scintillation counter. Gut retentions were calculated as the difference: whole body minus carcass. All animals fed meat, bread or milk had much higher body retentions than animals fed rat diet. Our results point out the importance of nutritional factors in metal metabolism and toxicity. (orig./MG) [de

  16. Avaliação do bombeamento de água em um sistema alimentado por painéis fotovoltaicos Water pumping in a system fed by photovoltaic panels

    Directory of Open Access Journals (Sweden)

    Roger N. Michels

    2009-09-01

    Full Text Available O presente trabalho foi desenvolvido com a finalidade de avaliar um sistema de bombeamento de água acionado por painéis fotovoltaicos instalados nas dependências da Universidade Tecnológica Federal do Paraná, Câmpus Medianeira - PR. O município está localizado no oeste paranaense (25º17'43" S; 54º03'38" e 500,7 m. O sistema trabalhou em situação real de funcionamento, bombeando água à altura de 20 m. Foram coletados dados de fevereiro a novembro de 2005; utilizou-se coletor de dados computadorizado da Campbell Scientific INC. , que possibilitou adquirir e armazenar os dados de irradiância solar no plano do painel, tensão e corrente gerada, temperatura no painel e vazão. Por meio de cálculos, obtiveram-se os valores de potência e eficiência do sistema. O solstício de inverno apresentou eficiência de 9,58% com bombeamento diário de 2.056 litros, enquanto o solstício de verão apresentou eficiência de 9,07% com bombeamento diário de 2.377 litros. A maior eficiência nos dias de inverno está ligada às menores temperaturas se comparada aos dias de verão, e o fator que provocou a maior vazão de água bombeada nos dias de verão está atrelado ao tempo de insolação, que é maior se comparado aos dias de inverno.The main objective of this paper is to evaluate a water pumping system powered by photovoltaic panels installed at Federal Technological University of Paraná - UTFPR, in Medianeira, State of Paraná, Brazil. The city is located at the West of Paraná (25º17'43"; 54º03'38" and 500.7 meters - 1,642.72 feet. The system operated in a real working situation, pumping water to 20 meters (65.62 feet of elevation. The data were collected, from February 2005 to November 2005, by means of a computerized data collector made by Campbell Scientific Inc that made possible to acquire and store irradiance values in the panel plane, generated current and voltage, panel temperature and outflow. Through calculations, the power and

  17. The hemolymph proteome of fed and starved Drosophila larvae.

    Science.gov (United States)

    Handke, Björn; Poernbacher, Ingrid; Goetze, Sandra; Ahrens, Christian H; Omasits, Ulrich; Marty, Florian; Simigdala, Nikiana; Meyer, Imke; Wollscheid, Bernd; Brunner, Erich; Hafen, Ernst; Lehner, Christian F

    2013-01-01

    The co-operation of specialized organ systems in complex multicellular organisms depends on effective chemical communication. Thus, body fluids (like blood, lymph or intraspinal fluid) contain myriads of signaling mediators apart from metabolites. Moreover, these fluids are also of crucial importance for immune and wound responses. Compositional analyses of human body fluids are therefore of paramount diagnostic importance. Further improving their comprehensiveness should increase our understanding of inter-organ communication. In arthropods, which have trachea for gas exchange and an open circulatory system, the single dominating interstitial fluid is the hemolymph. Accordingly, a detailed analysis of hemolymph composition should provide an especially comprehensive picture of chemical communication and defense in animals. Therefore we used an extensive protein fractionation workflow in combination with a discovery-driven proteomic approach to map out the detectable protein composition of hemolymph isolated from Drosophila larvae. Combined mass spectrometric analysis revealed more than 700 proteins extending far beyond the previously known Drosophila hemolymph proteome. Moreover, by comparing hemolymph isolated from either fed or starved larvae, we provide initial provisional insights concerning compositional changes in response to nutritional state. Storage proteins in particular were observed to be strongly reduced by starvation. Our hemolymph proteome catalog provides a rich basis for data mining, as exemplified by our identification of potential novel cytokines, as well as for future quantitative analyses by targeted proteomics.

  18. The hemolymph proteome of fed and starved Drosophila larvae.

    Directory of Open Access Journals (Sweden)

    Björn Handke

    Full Text Available The co-operation of specialized organ systems in complex multicellular organisms depends on effective chemical communication. Thus, body fluids (like blood, lymph or intraspinal fluid contain myriads of signaling mediators apart from metabolites. Moreover, these fluids are also of crucial importance for immune and wound responses. Compositional analyses of human body fluids are therefore of paramount diagnostic importance. Further improving their comprehensiveness should increase our understanding of inter-organ communication. In arthropods, which have trachea for gas exchange and an open circulatory system, the single dominating interstitial fluid is the hemolymph. Accordingly, a detailed analysis of hemolymph composition should provide an especially comprehensive picture of chemical communication and defense in animals. Therefore we used an extensive protein fractionation workflow in combination with a discovery-driven proteomic approach to map out the detectable protein composition of hemolymph isolated from Drosophila larvae. Combined mass spectrometric analysis revealed more than 700 proteins extending far beyond the previously known Drosophila hemolymph proteome. Moreover, by comparing hemolymph isolated from either fed or starved larvae, we provide initial provisional insights concerning compositional changes in response to nutritional state. Storage proteins in particular were observed to be strongly reduced by starvation. Our hemolymph proteome catalog provides a rich basis for data mining, as exemplified by our identification of potential novel cytokines, as well as for future quantitative analyses by targeted proteomics.

  19. Development of a Gas-Fed Pulse Detonation Research Engine

    Science.gov (United States)

    Litchford, Ron J.; Hutt, John (Technical Monitor)

    2001-01-01

    In response to the growing need for empirical data on pulse detonation engine performance and operation, NASA Marshall Space Flight Center has developed and placed into operation a low-cost gas-fed pulse detonation research engine. The guiding design strategy was to achieve a simple and flexible research apparatus, which was inexpensive to build and operate. As such, the engine was designed to operate as a heat sink device, and testing was limited to burst-mode operation with run durations of a few seconds. Wherever possible, maximum use was made of standard off-the-shelf industrial or automotive components. The 5-cm diameter primary tube is about 90-cm long and has been outfitted with a multitude of sensor and optical ports. The primary tube is fed by a coaxial injector through an initiator tube, which is inserted directly into the injector head face. Four auxiliary coaxial injectors are also integrated into the injector head assembly. All propellant flow is controlled with industrial solenoid valves. An automotive electronic ignition system was adapted for use, and spark plugs are mounted in both tubes so that a variety of ignition schemes can be examined. A microprocessor-based fiber-optic engine control system was developed to provide precise control over valve and ignition timing. Initial shakedown testing with hydrogen/oxygen mixtures verified the need for Schelkin spirals in both the initiator and primary tubes to ensure rapid development of the detonation wave. Measured pressure wave time-of-flight indicated detonation velocities of 2.4 km/sec and 2.2 km/sec in the initiator and primary tubes, respectively. These values implied a fuel-lean mixture corresponding to an H2 volume fraction near 0.5. The axial distribution for the detonation velocity was found to be essentially constant along the primary tube. Time-resolved thrust profiles were also acquired for both underfilled and overfilled tube conditions. These profiles are consistent with previous time

  20. Feed efficiency differences and reranking in beef steers fed grower and finisher diets.

    Science.gov (United States)

    Durunna, O N; Mujibi, F D N; Goonewardene, L; Okine, E K; Basarab, J A; Wang, Z; Moore, S S

    2011-01-01

    This 3-yr study used 490 steers to determine whether feedlot steers changed their feed efficiency (FE) ranking when fed a grower diet, then a finisher diet. The steers were crossbreds and were between 5 to 7 mo of age. There were 2 feeding periods each year. Within each year, approximately 90 steers had their diet switched from a grower to a finisher diet (feed-swap group), whereas another 90 steers were fed either the grower (grower-fed group) or the finisher (finisher-fed group) diet throughout the feeding trial. Each feeding test lasted for a minimum of 10 wk, and all steers were fed ad libitum. Individual animal feed intakes were collected using the GrowSafe feeding system, and BW were measured every 2 wk. Residual feed intake (RFI), G:F, and Kleiber ratio (KR) were computed at the end of each feeding period. For each measure of efficiency, animals were classified as low, medium, or high based on 0.5 SD from the mean. The majority of steers did not maintain the previous efficiency class in the second period. Approximately 58, 51, and 51% of steers in the feed-swap group, finisher-fed group, and the grower-fed group, respectively, changed their RFI measure by 0.5 SD. A low rank correlation occurred in all test groups but was less in the feed-swap group. Spearman rank correlations between the 2 feeding periods in the feed-swap group were 0.33, 0.20, and 0.31 for RFI, G:F, and KR, respectively. Classifications based on G:F and KR showed that a greater number of steers (P 0.05) between the proportions of individuals that changed or maintained their FE class. In the groups without a feed-swap, there was no difference (P > 0.05) in the proportion of steers that changed or maintained the same FE class for all FE measures. Our results suggest that diet type and feeding period affect the FE ranking in beef steers. A feedlot diet is ideal for evaluating the FE potential of steers for feedlot profitability; however, we suggest that tests involving less dense diets should

  1. Performance of chicken broilers fed with diets substituted with ...

    African Journals Online (AJOL)

    Performance of chicken broilers fed with diets substituted with mulberry leaf powder. Carlina Freddie Simol, Andrew Alek Tuen, Humrawali Hazid Ahmad Khan, John Keen Chubo, Patricia Jie Hung King, Kian Huat Ong ...

  2. Secretion of hepatic triglycerides into plasma of rats fed retinol

    International Nuclear Information System (INIS)

    Ahuja, H.C.; Misra, U.K.

    1975-01-01

    The effect of feeding 33 mg of retinol daily for two days on liver and plasma lipids of rats has been studied. The secretion of liver TG into plasma of retinol fed rats has been measured by the use of palmitic acid-1- 14 C and of Triton WR 1339. Liver and plasma lipids, TG, phospholipids and PC were significantly higher in retinol fed rats as compared to control rats. The incorporation of palmitic acid-1- 14 C into liver TG, PC and PE was significantly higher in retinol fed rats. The labelling pattern with time of liver and plasma TG and PC shows that the secretion of liver TG and PC into plasma was impaired in retinol fed rats. (auth.)

  3. Protein, energy and phosphorus supplementation of cattle fed low ...

    African Journals Online (AJOL)

    The effect of protein, energy and phosphorus supplements, fed ..... The results of this experiment confirm the basic concepts that ... article. The lack of response or even negative reaction to energy supplements under these conditions can be ...

  4. Factorial analysis of slaughter characteristics of fattening pigs fed ...

    African Journals Online (AJOL)

    Jane

    2011-08-08

    Aug 8, 2011 ... Slaughter characteristics in three groups of fattening pigs fed in different ways were ... INTRODUCTION. Probiotic preparations are used as food additives ...... Effect of use of Vitaprotein 50 as fish meal substitute in nutrition of.

  5. Performance of broiler chickens fed on Moringa oleifera leaf meal ...

    African Journals Online (AJOL)

    Performance of broiler chickens fed on Moringa oleifera leaf meal ... This exploratory study was conducted to investigate the effect of Moringa oleifera leaf meal ... ratio were evaluated for the individual replicate of each dietary treatment.

  6. Testicular damage in rats fed on irradiated diets

    International Nuclear Information System (INIS)

    Kushwaha, A.K.S.; Hasan, S.S.

    1986-01-01

    Feeding effect of irradiated diets was studied on the pups born to mother fed either on irradiated normal diet or irradiated low protein diet. The study indicated that pups born to mother fed on the irradiated low protein diet had fewer spermatogonial cells in the testes than those given irradiated normal diet and unirradiated low protein diet. Similarly, pups maintained on the irradiated low protein diet showed marked decrease in alkaline phosphatase and cholesterol contents in the testes rather than in the pups fed irradiated normal as well as unirradiated low protein diets. The irradiated low protein diet fed pups showed increased depletion and vacuolization of adrenocortical and medullary cells. 13 refs., 15 figures. (author)

  7. Testicular damage in rats fed on irradiated diets

    Energy Technology Data Exchange (ETDEWEB)

    Kushwaha, A K.S.; Hasan, S S

    1986-12-01

    Feeding effect of irradiated diets was studied on the pups born to mother fed either on irradiated normal diet or irradiated low protein diet. The study indicated that pups born to mother fed on the irradiated low protein diet had fewer spermatogonial cells in the testes than those given irradiated normal diet and unirradiated low protein diet. Similarly, pups maintained on the irradiated low protein diet showed marked decrease in alkaline phosphatase and cholesterol contents in the testes rather than in the pups fed irradiated normal as well as unirradiated low protein diets. The irradiated low protein diet fed pups showed increased depletion and vacuolization of adrenocortical and medullary cells. 13 refs., 15 figures.

  8. Assessment of the haematological indices of albino rats fed diets ...

    African Journals Online (AJOL)

    Keywords: Haematology, jackfruit, bulb, seed, supplementation. INTRODUCTION ... Albokhadaim, 2015) and humans (Lavy,. 1994 .... Table 2: Body weights and daily food intake of control and rats fed jackfruit seed diet (g). Experimental.

  9. Body weight and carcass characteristics of broilers fed different ...

    African Journals Online (AJOL)

    Body weight and carcass characteristics of broilers fed different mixtures of ... Journal of Agriculture, Forestry and the Social Sciences ... The experimental diets (starter and finisher diets) were offered to the respective bids with water ad libitum.

  10. Simulation of Feedforward-Feedback Control of Dissolved Oxygen of Microbial Repeated Fed-batch Culture

    Directory of Open Access Journals (Sweden)

    Ling Gao

    2016-09-01

    Full Text Available Fed-batch culture is often used in industry, and dissolved oxygen (DO concentration control is important in fermentation process control. DO control is often applied by using feedback (FB control strategy. But, feedforward-feedback (FF-FB control has the advantage in dealing with the time-varying characteristics resulted from the cell growth during the fermentation process. Mathematical modeling and computer simulation is a useful tool in analysis of the control system.  In this research, the FF-FB DO control and FB substrate control of repeated fed-batch culture process is modeled and simulated. The results showed the feasibility of the control strategy. These results are useful for control system development and process analyses and optimization.

  11. Neural network based control of Doubly Fed Induction Generator in wind power generation

    Science.gov (United States)

    Barbade, Swati A.; Kasliwal, Prabha

    2012-07-01

    To complement the other types of pollution-free generation wind energy is a viable option. Previously wind turbines were operated at constant speed. The evolution of technology related to wind systems industry leaded to the development of a generation of variable speed wind turbines that present many advantages compared to the fixed speed wind turbines. In this paper the phasor model of DFIG is used. This paper presents a study of a doubly fed induction generator driven by a wind turbine connected to the grid, and controlled by artificial neural network ANN controller. The behaviour of the system is shown with PI control, and then as controlled by ANN. The effectiveness of the artificial neural network controller is compared to that of a PI controller. The SIMULINK/MATLAB simulation for Doubly Fed Induction Generator and corresponding results and waveforms are displayed.

  12. Sizing of the Series Dynamic Breaking Resistor in a Doubly Fed Induction Generator Wind Turbine

    DEFF Research Database (Denmark)

    Soliman, Hammam; Wang, Huai; Zhou, Dao

    2014-01-01

    This paper investigates the effect of Series Dynamic Breaking Resistor (SDBR) sizing on a Doubly Fed Induction Generator (DFIG) based wind power conversion system. The boundary of the SDBR value is firstly derived by taking into account the controllability of the rotor side converter and the maxi......This paper investigates the effect of Series Dynamic Breaking Resistor (SDBR) sizing on a Doubly Fed Induction Generator (DFIG) based wind power conversion system. The boundary of the SDBR value is firstly derived by taking into account the controllability of the rotor side converter...... and the maximum allowable voltage of the stator. Then the impact of the SDBR value on the rotor current, stator voltage, DC-link voltage, reactive power capability and introduced power loss during voltage sag operation is evaluated by simulation. The presented study enables a trade-off sizing of the SDBR among...

  13. Doubly Fed Induction Generator Wind Turbines with Fuzzy Controller: A Survey

    Directory of Open Access Journals (Sweden)

    J. S. Sathiyanarayanan

    2014-01-01

    Full Text Available Wind energy is one of the extraordinary sources of renewable energy due to its clean character and free availability. With the increasing wind power penetration, the wind farms are directly influencing the power systems. The majority of wind farms are using variable speed wind turbines equipped with doubly fed induction generators (DFIG due to their advantages over other wind turbine generators (WTGs. Therefore, the analysis of wind power dynamics with the DFIG wind turbines has become a very important research issue, especially during transient faults. This paper presents fuzzy logic control of doubly fed induction generator (DFIG wind turbine in a sample power system. Fuzzy logic controller is applied to rotor side converter for active power control and voltage regulation of wind turbine.

  14. Doubly fed induction generator wind turbines with fuzzy controller: a survey.

    Science.gov (United States)

    Sathiyanarayanan, J S; Kumar, A Senthil

    2014-01-01

    Wind energy is one of the extraordinary sources of renewable energy due to its clean character and free availability. With the increasing wind power penetration, the wind farms are directly influencing the power systems. The majority of wind farms are using variable speed wind turbines equipped with doubly fed induction generators (DFIG) due to their advantages over other wind turbine generators (WTGs). Therefore, the analysis of wind power dynamics with the DFIG wind turbines has become a very important research issue, especially during transient faults. This paper presents fuzzy logic control of doubly fed induction generator (DFIG) wind turbine in a sample power system. Fuzzy logic controller is applied to rotor side converter for active power control and voltage regulation of wind turbine.

  15. Overall control strategy of variable speed doubly-fed induction generator wind turbine

    Energy Technology Data Exchange (ETDEWEB)

    Hansen, Anca D.; Soerensen, Poul [Risoe National Laboratory, Roskilde (Denmark). Wind Energy Dept.; Iov, Florin; Blaabjerg, Frede [Aalborg Univ. (Denmark). Inst. of Energy Technology

    2004-07-01

    The variable speed doubly-fed induction generator wind turbine is today the most widely used concept. The paper presents an overall control system of the variable speed DFIG wind turbine, with focus on the control strategies and algorithms applied at each hierarchical control level of the wind turbine. The present control method is designed for normal continuous operations. The strongest feature of the implemented control method is that it allows the turbine to operate with the optimum power efficiency over a wider range of wind speeds. The variable speed/variable pitch wind turbine with doubly-fed induction generator is implemented in the dynamic power system simulation tool DIgSILENT. Simulation results are performed and analyzed in different normal operating conditions.

  16. [Aortic and cerebral trombosis caused by hypernatremic dehydration in an exclusively breast-fed infant].

    Science.gov (United States)

    Iglesias Fernández, C; Chimenti Camacho, P; Vázquez López, P; Guerrero Soler, M; Blanco Bravo, D

    2006-10-01

    Complete aortic thrombosis is rare in neonates. Because it carries high morbidity and mortality, this entity requires aggressive and early treatment. This report describes an 8-day-old healthy and exclusively breast-fed infant, without specific coagulopathy, who developed complete aortic and cerebral venous thrombosis, which was attributed to inadequate breast-feeding and severe hypernatremic dehydration. Early systemic anticoagulation and thrombolytic therapy allowed complete resolution of the problem.

  17. Wearable Inset-Fed FR4 Microstrip Patch Antenna Design

    Science.gov (United States)

    Zaini, S. R. Mohd; Rani, K. N. Abdul

    2018-03-01

    This project proposes the design of a wireless body area network (WBAN) microstrip patch antenna covered by the jeans fabric as the outer layer operating at the center frequency, fc of 2.40 GHz. Precisely, the microstrip patch antenna with the inset-fed edge technique is designed and simulated systematically by using the Keysight Advanced Design System (ADS) software where the FR4 board with the dielectric constant, ɛr of 4.70, dissipation factor or loss tangent, tan δ of 0.02 and height, h of 1.60 mm is the chosen dielectric substrate. The wearable microstrip patch antenna design is then fabricated using the FR4 printed circuit board (PCB) material, hidden inside the jeans fabric, and attached to clothing, such as a jacket accordingly. Simulation and fabrication measurement results show that the designed microstrip patch antenna characteristics can be applied significantly within the industrial, scientific, and medical (ISM) radio band, which is at fc = 2.40 GHz.

  18. Sheep fed with banana leaf hay reduce ruminal protozoa population.

    Science.gov (United States)

    Freitas, Cláudio Eduardo Silva; Duarte, Eduardo Robson; Alves, Dorismar David; Martinele, Isabel; D'Agosto, Marta; Cedrola, Franciane; de Moura Freitas, Angélica Alves; Dos Santos Soares, Franklin Delano; Beltran, Makenzi

    2017-04-01

    A ciliate protozoa suppression can reduce methane production increasing the energy efficiency utilization by ruminants. The physicochemical characteristics of rumen fluid and the profile of the rumen protozoa populations were evaluated for sheep fed banana leaf hay in replacement of the Cynodon dactylon cv. vaqueiro hay. A total of 30 male sheep were raised in intensive system during 15 days of adaptation and 63 days of experimental period. The animals were distributed in a completely randomized design that included six replicates of five treatments with replacement levels (0, 25, 50, 75, and 100%) of the grass vaquero for the banana leaf hay. Samples of fluid were collected directly from the rumen with sterile catheters. Color, odor, viscosity, and the methylene blue reduction potential (MBRP) were evaluated and pH estimated using a digital potentiometer. After decimal dilutions, counts of genus protozoa were performed in Sedgewick Rafter chambers. The averages of pH, MBRP, color, odor, and viscosity were not influenced by the inclusion of the banana leaf hay. However, the total number of protozoa and Entodinium spp. population significantly decreased at 75 and 100% inclusions of banana leaf hay as roughage.

  19. CoQ10 plasmatic levels in breast-fed infants compared to formula-fed infants.

    Science.gov (United States)

    Compagnoni, G; Giuffrè, B; Lista, G; Mosca, F; Marini, A

    2004-01-01

    Coenzyme Q10 has been recognized as an important antioxidant factor besides its main role in bioenergetic metabolism. CoQ10 tissue levels depend both on exogenous dietetic intake and on endogenous biosynthesis, as this compound can be partly synthesized in human cells. Q10 plasma levels reflect the tissue content of the coenzyme and can be used to evaluate the presence of this compound in the human organism. Aim of the study was to measure CoQ10 plasmatic levels in a newborn breast-fed population and to compare them to CoQ10 levels in a newborn formula-fed population in order to verify whether changes in CoQ10 plasmatic contents could be related to a different dietetic intakes. We measured CoQ10 plasmatic levels in 25 healthy term neonates with different dietetic intakes: 15 breast-fed and 10 bottle-fed with a common infant formula. These infants were evaluated prospectively during the first month of life. The analyses were performed on the mothers' blood samples and cord blood samples at the time of delivery, then on infants at 4 and 28 days of age. Our results showed markedly reduced Q10 levels in cord blood samples compared to maternal Q10 plasmatic levels at the time of delivery, suggesting placental impermeability towards this molecule or increased fetal utilization during labor and delivery. At 4 days of age Q10 levels had increased in both groups of neonates, but significantly more in breast-fed infants compared to formula-fed babies (p <0.05). At 4 weeks of age no significant changes occurred in breast-fed infants, while values increased significantly in formula-fed infants (p <0.05). The content of Q10 in breast milk samples was lower than in infant formula. The results of this study show that CoQ10 plasmatic levels are at least partly influenced by the exogenous dietetic supply.

  20. Classification system for rain fed wheat grain cultivars using artificial ...

    African Journals Online (AJOL)

    Jane

    2011-08-03

    Aug 3, 2011 ... Artificial neural network (ANN) models have found wide applications, including prediction, ... number of hidden layers, this study was done in Islamic Azad University, Shahr-e-Rey Branch, during ... External features describe the boundary information. ... based on Bayes decision theory to classify rice variety.

  1. Microcirculatory effects of zinc on fructose-fed hamsters.

    Science.gov (United States)

    Castiglione, R C; Barros, C M M R; Boa, B C S; Bouskela, E

    2016-04-01

    Fructose is a major dietary component directly related to vascular dysfunction and diseases such as obesity, diabetes, and hypertension. Zinc is considered a non-pharmacological alternative for treating diabetes due to its antioxidant and hyperglycemia-lowering effects in diabetic animals. Therefore, the aim of this study was to evaluate the effects of dietary zinc supplementation on the microcirculatory parameters of fructose-fed hamsters. Male hamsters (Mesocricetus auratus) were fed drinking water substituted by 10% fructose solution for 60 days, whereas control animals were fed drinking water alone. Their microcirculatory function was evaluated using cheek pouch preparation, as well as their blood glucose and serum insulin levels. Their microcirculatory responses to acetylcholine (ACh, an endothelium-dependent vasodilator) and to sodium nitroprusside (SNP, an endothelium-independent vasodilator) as well as the increase in macromolecular permeability induced by 30 min of ischemia/reperfusion (I/R) were noted. Endothelium-dependent vasodilation was significantly increased in control animals with high zinc supplementation compared to the groups without zinc supplementation. Zinc was able to protect against plasma leakage induced by I/R in all control and fructose-fed groups, although the microvascular permeability was higher in animals fed drinking water substituted by 10% fructose solution compared to those fed filtered drinking water alone. Our results indicate that dietary zinc supplementation can improve microvascular dysfunction by increasing endothelial-dependent dilatation and reducing the increase in macromolecular permeability induced by I/R in fructose-fed animals. Copyright © 2015 The Italian Society of Diabetology, the Italian Society for the Study of Atherosclerosis, the Italian Society of Human Nutrition, and the Department of Clinical Medicine and Surgery, Federico II University. Published by Elsevier B.V. All rights reserved.

  2. A novel model-based control strategy for aerobic filamentous fungal fed-batch fermentation processes

    DEFF Research Database (Denmark)

    Mears, Lisa; Stocks, Stuart M.; Albaek, Mads O.

    2017-01-01

    A novel model-based control strategy has been developed for filamentous fungal fed-batch fermentation processes. The system of interest is a pilot scale (550 L) filamentous fungus process operating at Novozymes A/S. In such processes, it is desirable to maximize the total product achieved...... is recursively updated using on-line measurements. The model was applied in order to predict the current system states, including the biomass concentration, and to simulate the expected future trajectory of the system until a specified end time. In this way, the desired feed rate is updated along the progress...

  3. Thermal and structural limitations for impurity-control components in FED/INTOR

    International Nuclear Information System (INIS)

    Majumdar, S.; Cha, Y.; Mattas, R.; Abdou, M.; Cramer, B.; Haines, J.

    1983-02-01

    The successful operation of the impurity-control system of the FED/INTOR will depend to a large extent on the ability of its various components to withstand the imposed thermal and mechanical loads. The present paper explores the thermal and stress analyses aspects of the limiter and divertor operation of the FED/INTOR in its reference configuration. Three basic limitations governing the design of the limiter and the divertor are the maximum allowable metal temperature, the maximum allowable stress intensity and the allowable fatigue life of the structural material. Other important design limitations stemming from sputtering, evaporation, melting during disruptions, etc. are not considered in the present paper. The materials considered in the present analysis are a copper and a vanadium alloy for the structural material and graphite, beryllium, beryllium oxide, tungsten and silicon carbide for the coating or tile material

  4. Fed-Batch Biomolecule Production by Bacillus subtilis: A State of the Art Review.

    Science.gov (United States)

    Ÿztürk, Sibel; Ÿalık, Pınar; Ÿzdamar, Tunçer H

    2016-04-01

    Bacillus subtilis is a highly promising production system for various biomolecules. This review begins with the algorithm of fed-batch operations (FBOs) and then illustrates the approaches to design the initial production medium and/or feed stream. Additionally, the feeding strategies developed with or without feedback control for fed-batch B. subtilis fermentations were compiled with a special emphasis on recombinant protein (r-protein) production. For biomolecule production by wild-type B. subtilis, due to the different intracellular production patterns, no consensus exists on the FBO strategy that gives the maximum productivity, whereas for r-protein production appropriate feeding strategies vary depending on the promoter used. Thus, we conclude that the B. subtilis community is still seeking an approved strong promoter and generalized FBO strategies. Copyright © 2015 Elsevier Ltd. All rights reserved.

  5. Electrochemical Characterisation of Bio-Bottle-Voltaic (BBV) Systems Operated with Algae and Built with Recycled Materials.

    Science.gov (United States)

    Bateson, Peter; Fleet, Jack E H; Riseley, Anthony S; Janeva, Elena; Marcella, Anastasia S; Farinea, Chiara; Kuptsova, Maria; Conde Pueyo, Núria; Howe, Christopher J; Bombelli, Paolo; Parker, Brenda M

    2018-04-17

    Photobioelectrochemical systems are an emerging possibility for renewable energy. By exploiting photosynthesis, they transform the energy of light into electricity. This study evaluates a simple, scalable bioelectrochemical system built from recycled plastic bottles, equipped with an anode made from recycled aluminum, and operated with the green alga Chlorella sorokiniana . We tested whether such a system, referred to as a bio-bottle-voltaic (BBV) device, could operate outdoors for a prolonged time period of 35 days. Electrochemical characterisation was conducted by measuring the drop in potential between the anode and the cathode, and this value was used to calculate the rate of charge accumulation. The BBV systems were initially able to deliver ~500 mC·bottle −1 ·day −1 , which increased throughout the experimental run to a maximum of ~2000 mC·bottle −1 ·day −1 . The electrical output was consistently and significantly higher than that of the abiotic BBV system operated without algal cells (~100 mC·bottle −1 ·day −1 ). The analysis of the rate of algal biomass accumulation supported the hypothesis that harvesting a proportion of electrons from the algal cells does not significantly perturb the rate of algal growth. Our finding demonstrates that bioelectrochemical systems can be built using recycled components. Prototypes of these systems have been displayed in public events; they could serve as educational toolkits in schools and could also offer a solution for powering low-energy devices off-grid.

  6. Electrochemical Characterisation of Bio-Bottle-Voltaic (BBV Systems Operated with Algae and Built with Recycled Materials

    Directory of Open Access Journals (Sweden)

    Peter Bateson

    2018-04-01

    Full Text Available Photobioelectrochemical systems are an emerging possibility for renewable energy. By exploiting photosynthesis, they transform the energy of light into electricity. This study evaluates a simple, scalable bioelectrochemical system built from recycled plastic bottles, equipped with an anode made from recycled aluminum, and operated with the green alga Chlorella sorokiniana. We tested whether such a system, referred to as a bio-bottle-voltaic (BBV device, could operate outdoors for a prolonged time period of 35 days. Electrochemical characterisation was conducted by measuring the drop in potential between the anode and the cathode, and this value was used to calculate the rate of charge accumulation. The BBV systems were initially able to deliver ~500 mC·bottle−1·day−1, which increased throughout the experimental run to a maximum of ~2000 mC·bottle−1·day−1. The electrical output was consistently and significantly higher than that of the abiotic BBV system operated without algal cells (~100 mC·bottle−1·day−1. The analysis of the rate of algal biomass accumulation supported the hypothesis that harvesting a proportion of electrons from the algal cells does not significantly perturb the rate of algal growth. Our finding demonstrates that bioelectrochemical systems can be built using recycled components. Prototypes of these systems have been displayed in public events; they could serve as educational toolkits in schools and could also offer a solution for powering low-energy devices off-grid.

  7. Antioxidant and anti-atherogenic activities of three Piper species on atherogenic diet fed hamsters.

    Science.gov (United States)

    Agbor, Gabriel A; Vinson, Joe A; Sortino, Julianne; Johnson, Robert

    2012-05-01

    Atherogenic diet is known to induce high plasma lipid concentration, oxidative stress and early atherosclerosis. Antioxidants have potentials to counter the effect of atherogenic diet. The present research aims at evaluating the antioxidant and anti-atherosclerotic activities of three Piper species (Piper guineense, Piper nigrum and Piper umbellatum) on atherogenic diet fed hamsters. Hamsters divided into 8 groups: normal control, atherosclerotic control and six test groups. The normal animals fed normal rodent chow, the atherosclerotic control animals fed the same rodent chow supplemented with 0.2% cholesterol and 10% coconut oil (high cholesterol diet). The 6 test groups' animals fed same diet as the atherosclerotic control group but with additional supplementation of 2 graded doses (1 and 0.25 mg/kg body weight, o.p.) of plant extracts for 12 weeks. The atherogenic diet induced a collapse of the erythrocyte antioxidant defense system (significant decrease in superoxide dismutase, catalase and glutathione peroxidase activities). Atherogenic diet also induced an increase in plasma total cholesterol, triglyceride, thiobarbituric acid reactive substances (TBARS), oxidation of low density lipoprotein cholesterol (LDL) and accumulation of foam cells in the aorta a hall mark for atherosclerosis. Administration of the Piper species prevented the collapse of the antioxidant system and the increase of plasma parameters maintaining them towards normality. The Piper species also prevented LDL oxidation by increasing the time (lag time) for its oxidation. The results suggest that these Piper species have significant antioxidant and anti-atherogenic effect against atherogenic diet intoxication. Copyright © 2010 Elsevier GmbH. All rights reserved.

  8. Growth and Reproduction of Artificially Fed Cnaphalocrocis medinalis

    Directory of Open Access Journals (Sweden)

    Jian XU

    2012-09-01

    Full Text Available The growth and reproduction of rice leaffolder, Cnaphalocrocis medinalis, fed on an artificial diet were studied. The results showed that the larvae were able to grow and pupate on the artificial diet. The durations of larvae and pupas of C. medinalis on the artificial diet were 28.1 d and 10.1 d, postponed 4.9 d and 1.7 d respectively, compared with those reared with rice leaves. The number of ovipositions was 41.6 per female, 26.2% higher than that fed on rice leaves. Survival rate curve of larvae was a descent function of mortality-age, with no significant differences from the curve of larvae fed on rice leaves. The net reproductive rate (Ro, intrinsic rate of increase (rm and finite rate of increase (λ of the population fed on diet were 17.6928, 0.0884 and 1.0924, respectively, and the mean generation time (T and double time (td were prolonged 4.9 d and 1.3 d in comparison with the treatment of rice leaves. Population trend index (I was 3.26, indicating a growing number of the population of C. medinalis fed on artificial diet.

  9. Single-Electrical-Port Control of Cascaded Doubly-Fed Induction Machine for EV/HEV Applications

    DEFF Research Database (Denmark)

    Han, Peng; Cheng, Ming; Chen, Zhe

    2017-01-01

    A single-electrical-port control scheme, for four-quadrant operation of cascaded doubly-fed induction machine (CDFIM), which has long been conceived as a motor or generator only suitable for limited two-quadrant operation, is proposed and theoretically demonstrated. The drive system is configured...... as slave inverter. With this configuration, the control emphasis is placed on the slave inverter, yielding reduced control complexity and cost, and the inaccuracy of flux estimation in conventional FOC for singly-fed induction machines is avoided at very low or even zero speed. It is found that the doubly...

  10. Optimization of fed-batch enzymatic hydrolysis from alkali-pretreated sugarcane bagasse for high-concentration sugar production.

    Science.gov (United States)

    Gao, Yueshu; Xu, Jingliang; Yuan, Zhenhong; Zhang, Yu; Liu, Yunyun; Liang, Cuiyi

    2014-09-01

    Fed-batch enzymatic hydrolysis process from alkali-pretreated sugarcane bagasse was investigated to increase solids loading, produce high-concentration fermentable sugar and finally to reduce the cost of the production process. The optimal initial solids loading, feeding time and quantities were examined. The hydrolysis system was initiated with 12% (w/v) solids loading in flasks, where 7% fresh solids were fed consecutively at 6h, 12h, 24h to get a final solids loading of 33%. All the requested cellulase loading (10 FPU/g substrate) was added completely at the beginning of hydrolysis reaction. After 120 h of hydrolysis, the maximal concentrations of cellobiose, glucose and xylose obtained were 9.376 g/L, 129.50 g/L, 56.03 g/L, respectively. The final total glucan conversion rate attained to 60% from this fed-batch process. Copyright © 2014. Published by Elsevier Ltd.

  11. Performance Improvement of Sensorless Vector Control for Induction Motor Drives Fed by Matrix Converter Using Nonlinear Model and Disturbance Observer

    DEFF Research Database (Denmark)

    Lee, Kyo-Beum; Blaabjerg, Frede

    2004-01-01

    This paper presents a new sensorless vector control system for high performance induction motor drives fed by a matrix converter with a non-linearity compensation and disturbance observer. The nonlinear voltage distortion that is caused by communication delay and on-state voltage drop in switching...

  12. Reduced Order Extended Luenberger Observer Based Sensorless Vector Control Fed by Matrix Converter with Non-linearity Modeling

    DEFF Research Database (Denmark)

    Lee, Kyo-Beum; Blaabjerg, Frede

    2004-01-01

    This paper presents a new sensorless vector control system for high performance induction motor drives fed by a matrix converter with non-linearity compensation. The nonlinear voltage distortion that is caused by commutation delay and on-state voltage drop in switching device is corrected by a new...

  13. Direct-fed microbials in broiler chickens challenged with Eimeria maxima or raised on Clostridium spp.-contaminated used litter

    Science.gov (United States)

    Dietary direct-fed microbials (DFMs) influence the composition of gut microbiota and enhance gut health in broiler chickens. Increasing scientific data have been gathered to show that gut microbiota plays an important role in the development of the immune system and the maintenance of homeostasis wi...

  14. Feasibility study of a pressure-fed engine for a water recoverable space shuttle booster. Volume 1: Executive summary

    Science.gov (United States)

    1972-01-01

    An overview is presented of the results of the analyses conducted in support of the selected engine system for the pressure-fed booster stage. During initial phases of the project, a gimbaled, regeneratively cooled, fixed thrust engine having a coaxial pintle injector was selected as optimum for this configuration.

  15. Stable nitrogen isotope ratios of macrophytes and associated periphyton along a nitrate gradient in two subtropical, spring-fed streams

    DEFF Research Database (Denmark)

    De Brabandere, Loreto; Frazer, Thomas K.; Montoya, Joseph P.

    2007-01-01

    , macrophytes and periphyton as a consequence of isotopic fractionation associated with preferential use of 14NO3-. This hypothesis was tested in two spring-fed river systems, the Chassahowitzka and Homosassa rivers, along Florida’s central Gulf of Mexico coast. 3. In general, d15N values of nitrate...

  16. Analysis of Microstrip Line Fed Patch Antenna for Wireless Communications

    Directory of Open Access Journals (Sweden)

    Singh Ashish

    2017-11-01

    Full Text Available In this paper, theoretical analysis of microstrip line fed rectangular patch antenna loaded with parasitic element and split-ring resonator is presented. The proposed antenna shows that the dualband operation depends on gap between parasitic element, split-ring resonator, length and width of microstrip line. It is found that antenna resonates at two distinct resonating modes i.e., 0.9 GHz and 1.8 GHz for lower and upper resonance frequencies respectively. The antenna shows dual frequency nature with frequency ratio 2.0. The characteristics of microstrip line fed rectangular patch antenna loaded with parasitic element and split-ring resonator antenna is compared with other prototype microstrip line fed antennas. Further, the theoretical results are compared with simulated and reported experimental results, they are in close agreement.

  17. FEDS : A Framework for Evaluation in Design Science Research

    DEFF Research Database (Denmark)

    Venable, John; Pries-Heje, Jan; Baskerville, Richard

    2015-01-01

    Evaluation of design artefacts and design theories is a key activity in Design Science Research (DSR), as it provides feedback for further development and (if done correctly) assures the rigour of the research. However, the extant DSR literature provides insufficient guidance on evaluation...... to enable Design Science Researchers to effectively design and incorporate evaluation activities into a DSR project that can achieve DSR goals and objectives. To address this research gap, this research paper develops, explicates, and provides evidence for the utility of a Framework for Evaluation in Design...... Science (FEDS) together with a process to guide design science researchers in developing a strategy for evaluating the artefacts they develop within a DSR project. A FEDS strategy considers why, when, how, and what to evaluate. FEDS includes a two-dimensional characterisation of DSR evaluation episodes...

  18. From Fed-batch to Continuous Enzymatic Biodiesel Production

    DEFF Research Database (Denmark)

    Price, Jason Anthony; Nordblad, Mathias; Woodley, John M.

    2015-01-01

    In this this paper, we use mechanistic modelling to guide the development of acontinuous enzymatic process that is performed as a fed-batch operation. In this workwe use the enzymatic biodiesel process as a case study. A mechanistic model developedin our previous work was used to determine...... measured components (triglycerides, diglycerides, monoglycerides, free fatty acid and fatty acid methyl esters(biodiesel)) much better than using fed-batch data alone given the smaller residuals. We also observe a reduction in the correlation between the parameters.The model was then used to predict that 5...... reactors are required (with a combined residence time of 30 hours) to reach a final biodiesel concentration within 2 % of the95.6 mass % achieved in a fed-batch operation, for 24 hours....

  19. Bioavailability of lead in rats fed human diets

    International Nuclear Information System (INIS)

    Kostial, K.; Kello, D.

    1979-01-01

    The bioavailability of lead was studied in rats fed various baby foods (Babymix-turkey, Babymix-vegetables, Frutolino-fruit, Frutamix-bananas, Babyron-S-26, Truefood), cow's milk, bread, liver and standard rat diet. Lead absorption was determined by measuring the whole body retention of 203 Pb 6 days after a single oral application. Highest absorption values ranging from 17 to 20% were obtained in animals fed cow's milk and fruit foods. Rats on other human diets absorbed between 3 and 8% of the radioactive lead dose. Only in animals on rat diet lead absorption was below 1%. It is concluded that rats fed human diets show absorption values similar to those in humans. This might indicate that the bioavailability of lead is primarily dependent on dietary habits. This experimental model, if confirmed by further work, might be useful for obtaining preliminary data on the bioavailability of metals from various foods

  20. Collaborative Modeling to Assess Drought   Resiliency of Snow‐Fed River Dependent  Communities in the Western United States:   A Case Study in the Truckee‐Carson River System

    Directory of Open Access Journals (Sweden)

    Loretta Singletary

    2017-02-01

    Full Text Available Assessing the drought resilience of snow‐fed river dependent communities in the arid  Western United States has taken on critical importance in response to changing climatic conditions.  The process of assessing drought resiliency involves understanding the extent to which snow‐fed  dependent communities can absorb the effects of uncertain and variable water supplies while  acknowledging and encouraging their capacity for adaptation. Participatory research approaches  are particularly well suited to assess resiliency in this context because they rely upon local water  managers’ knowledge and perspectives. The research presented here provides measured insight  into local water managers’ perceptions of drought resiliency in the Truckee‐Carson River System in  northwestern Nevada. These findings are reported in the context of the collaborative modeling  research design developed for this case study. The objectives of this study are: (1 to define  resiliency and present a rationale for a participatory approach to assess drought resiliency in  snow‐fed arid river basins in the Western United States; (2 to outline collaborative modeling as a  participatory research design developed for the Truckee‐Carson River System case study area; (3  to  describe  the  development and implementation of a resiliency  assessment  undertaken  to  implement this research design; (4 to highlight selected results of the assessment, summarizing  interviews with 66 water managers in the case study area; (5 to discuss the use of assessment  findings to inform collaborative modeling toward adaptation strategies; and (6 to review lessons  learned  to  date  from  the  collaborative  modeling  case  study  and  note

  1. Comparing a Dynamic Fed-Batch and a Continuous Steady-State Simulation of Ethanol Fermentation in a Distillery to a Stoichiometric Conversion Simulation

    OpenAIRE

    Fonseca, G.C.; Costa, C.B.B.; Cruz, A.J.G.

    2017-01-01

    Abstract An autonomous sugarcane bioethanol plant was simulated in EMSO software, an equation oriented process simulator. Three types of fermentation units were simulated: a six parallel fed-batch reactor system, a set of four CSTR in steady state and one consisting of a single stoichiometric reactor. Stoichiometric models are less accurate than kinetic-based fermentation models used for fed-batch and continuous fermenter simulations, since they do not account for inhibition effects and depen...

  2. Ultra-Wideband Notched Characteristic Fed by Coplanar Waveguide

    Directory of Open Access Journals (Sweden)

    Rastanto Hadinegoro

    2015-02-01

    Full Text Available In this paper, a novel Ultra-Wide Band (UWB notch patch antenna with co-planar waveguide (CPW fed is presented. This antenna only used one layer and the patch antenna is constructed on the first layer and back to back with CPW fed and bottom part is ground plane. The width notch is used to achieve the UWB characteristic. The results shown that the impedance bandwidth is 1130 MHz (1.662–2.792 GHz or about 50.7% for VSWR <2.

  3. Symbolic Solution Approach to Wind Turbine based on Doubly Fed Induction Generator Model

    DEFF Research Database (Denmark)

    Cañas–Carretón, M.; Gómez–Lázaro, E.; Martín–Martínez, S.

    2015-01-01

    –order induction generator is selected to model the electric machine, being this approach suitable to estimate the DFIG performance under transient conditions. The corresponding non–linear integro-differential equation system has been reduced to a linear state-space system by using an ad-hoc local linearization......This paper describes an alternative approach based on symbolic computations to simulate wind turbines equipped with Doubly–Fed Induction Generator (DFIG). The actuator disk theory is used to represent the aerodynamic part, and the one-mass model simulates the mechanical part. The 5th...

  4. Study on Modelling Standardization of Double-fed Wind Turbine and Its Application

    Directory of Open Access Journals (Sweden)

    Li Xiang

    2016-01-01

    Full Text Available Based on the standardized modelling of the International Modelling Team, study on double-fed induction generator (DFIG wind turbine is processed in this paper, aiming at capability of universally and reasonably reflecting key performance related to large scale system analysis. The standardized model proposed is of high degree of structural modularity, easy functional extension and universalization of control strategy and signal. Moreover, it is applicable for wind turbines produced by different manufacturers through model parameter adjustment. The complexity of the model can meet both needs of grid-connected characteristic simulation of wind turbine and large scale power system simulation.

  5. Centralised control of wind farm with doubly-fed induction generators

    DEFF Research Database (Denmark)

    Hansen, A.D.; Sørensen, Poul Ejnar; Iov, F.

    2005-01-01

    This paper describes the development of an advanced wind farm controller for a wind farm made-up exclusively of doubly-fed generators. The overall aim of such controller is to enable the wind farms to behave as active controllable components in the power system. The attention is mainly drawn...... to the ability of the wind farm control strategy to regulate the wind farm power production to the reference power ordered by the system operators. The performance of the control strategy is assessed and discussed by means of normal operation simulations of a grid connected wind farm....

  6. Advanced control of a doubly-fed induction generator for wind energy conversion

    Energy Technology Data Exchange (ETDEWEB)

    Poitiers, F.; Bouaouiche, T.; Machmoum, M. [Institut de Recherche en Electronique et Electrotechnique de Nantes Atlantique, rue Christian Pauc, 44306 Nantes (France)

    2009-07-15

    The aim of this paper is to propose a control method for a doubly-fed induction generator used in wind energy conversion systems. First, stator active and reactive powers are regulated by controlling the machine inverter with three different controllers: proportional-integral, polynomial RST based on pole placement theory and Linear Quadratic Gaussian. The machine is tested in association with a wind-turbine emulator. Secondly a control strategy for the grid-converter is proposed. Simulations results are presented and discussed for each converter control and for the whole system. (author)

  7. Performance of broiler chicken fed varied nutrient density diets supplemented with direct fed microbial

    Directory of Open Access Journals (Sweden)

    Katoch S.

    2013-01-01

    Full Text Available Comparative dietary response of different isolated strains (Direct fed microbial- DFM of lactobacilli, streptococci and yeast isolated from leopard feces (Panthera leo was studied as probiotic in poultry broiler birds reared as per varied mineral densities viz. calcium and phosphorus. Various treatments consisted of T0 (Control, culture medium, T1 (Lactobacillus casei + Streptococcus fecalis + Saccharomyces cerevisiae offered standard formulated diet D1, T2 - Control (Culture medium offered ten percent lower calcium and phosphorus diet D2, T3 (Lactobacillus casei + Streptococcus fecalis + Saccharomyces cerevisiae offered ten percent lower calcium and phosphorus diet D2. Growth results obtained during the starter phase (1st to 3rd week exhibited higher gain in live body weight and lower feed conversion ratio, both by DFM supplemented treatment T1 offered standard formulated diet D1 and treatment T3 offered experimentally formulated mineral (Ca and P deficient (10% diet D2 compared to respective control T0 and T2. The obtained results revealed a significantly higher growth performance in treatment T1 compared to its control T0 where a higher growth in treatment T3 offered experimentally formulated mineral (Ca and P deficient (10% diet D2 supplemented with isolated DFM compared to its control T2 was exhibited. Treatment groups T1 and T3 supplemented with isolated DFM exhibited a better intestinal micro flora balance, effective colonization and higher count in the intestinal tract with higher calcium and phosphorus retention in the digestibility studies. Thus, it was found that supplementation of isolated DFM has the potential to improve biological growth performance of poultry broiler birds offered both standard formulated diet D1, as well as mineral deficient diet D2. [Projekat Ministarstva nauke Republike Srbije, br. III 46002

  8. Effects of α-lipoic acid on endothelial function in aged diabetic and high-fat fed rats

    Science.gov (United States)

    Sena, C M; Nunes, E; Louro, T; Proença, T; Fernandes, R; Boarder, M R; Seiça, R M

    2007-01-01

    Background and purpose: This study was conducted to investigate the effects of α-lipoic acid (α-LA) on endothelial function in diabetic and high-fat fed animal models and elucidate the potential mechanism underlying the benefits of α-LA. Experimental approach: Plasma metabolites reflecting glucose and lipid metabolism, endothelial function, urinary albumin excretion (UAE), plasma and aortic malondialdehyde (MDA) and urinary 8-hydroxydeoxyguanosine (8-OHdG) were assessed in non-diabetic controls (Wistar rats), untreated Goto-Kakizaki (GK) diabetic and high-fat fed GK rats (fed with atherogenic diet only, treated with α-LA and treated with vehicle, for 3 months). Vascular eNOS, nitrotyrosine, carbonyl groups and superoxide anion were also assessed in the different groups. Key results: α-LA and soybean oil significantly reduced both total and non-HDL serum cholesterol and triglycerides induced by atherogenic diet. MDA, carbonyl groups, vascular superoxide and 8-OHdG levels were higher in GK and high-fat fed GK groups and fully reversed with α-LA treatment. High-fat fed GK diabetic rats showed significantly reduced endothelial function and increased UAE, effects ameliorated with α-LA. This endothelial dysfunction was associated with decreased NO production, decreased expression of eNOS and increased vascular superoxide production and nitrotyrosine expression. Conclusions and implications: α-LA restores endothelial function and significantly improves systemic and local oxidative stress in high-fat fed GK diabetic rats. Improved endothelial function due to α-LA was at least partially attributed to recoupling of eNOS and increased NO bioavailability and represents a pharmacological approach to prevent major complications associated with type 2 diabetes. PMID:17906683

  9. Performance of growing Yankasa rams Fed graded levels of ...

    African Journals Online (AJOL)

    A feeding trial which lasted eight (8) weeks was carried out to determine the intake and nutrient digestibility by growing Yankasa rams fed graded levels of Tamarindus indica leaves. Twelve Yankasa rams with average liveweight of 17.40kg were randomly allocated to three treatments of four replicates in a Randomized ...

  10. Sensory evaluation and tibia bone retention of broiler chicken fed ...

    African Journals Online (AJOL)

    An experiment was conducted for 56 days to assess the sensory evaluation of breast meat sample and tibia bone mineralization of broiler chicken fed graded level of toasted sesame seed meal. One hundred and eighty arbor acre chicks were divided into five dietary treatments. Each treatment was replicated thrice with ...

  11. Defense.gov Special Report: Feds Feed Families 2014

    Science.gov (United States)

    visit the Capital Area Food Bank. The Corporation for National and Community Service has the United We virtually! Order food online and have it sent to a food bank of your choice. Instructions Campaign Materials Capital Area Food Bank Feeding America Ample Harvest 2013 DoD Feds Feed Families Website . Main Menu Home

  12. Defense.gov Special Report: Feds Feed Families

    Science.gov (United States)

    defense for civilian personnel policy. Story Mark McCaffrey Featured at FFF Rally Capital Area Food Bank community. For more information visit the Capital Area Food Bank. The Corporation for National and Community Feds Feed Families Website Capital Area Food Bank What Others Are Doing FFF People, Pets and Paper

  13. Genital tract morphometry and haematology of male rabbits fed ...

    African Journals Online (AJOL)

    Genital tract morphometry and haematology of male rabbits fed graded levels of cassava leaf meal. ... It was concluded that the inclusion of up to 27% of CLM in bucks' diets is not detrimental to good health and normal reproductive tract development. It is recommended that further studies on the feeding potentials of ...

  14. Performance of weaner rabbits fed with varying levels of Tridax ...

    African Journals Online (AJOL)

    Twenty four weaner rabbits (mongrel breed) of both sexes with average weight of 350g were fed formulated diet comprising 0, 15, 30 and 45% Tridax procumbens (TRP). The parameters evaluated were nutrient intake, daily weight gain, feed, conversion ratio, incidences of diarrhoea and mortality. At the end of the study, ...

  15. Growth Performance of Red Sokoto Bucks Fed Inclusion levels of ...

    African Journals Online (AJOL)

    This study was carried out to evaluate the growth performance of red Sokoto bucks fed two (2) inclusion levels of rawwater soaked and lime soaked Hibiscus sabdariffa seeds in rice offal based diets. A total of twenty one (21) red Sokoto bucks were randomly allotted into seven treatments with three (3) bucks per group while ...

  16. Feeding behavior in lambs fed diets containing crambe cake

    Directory of Open Access Journals (Sweden)

    Mirna Adriane Syperreck

    2016-09-01

    Full Text Available It was evaluated the feeding behavior of lambs fed diets containing 30% sorghum silage and 70% crambe cake (30:70 diet, and 70% sorghum silage and 30% crambe cake (70:30 diet under voluntary and controlled consumption. The experimental design used was a 4 × 4 Latin square, with four animals, four periods, and four treatments; feeding behavior was determined by observation. The results indicated that animals fed the 30:70 diet showed higher DM and NDF (g day-1 than those fed the 70:30 diet. Animals fed the 70:30 diet showed longer feeding times (h kg-1 DM, mastication (min kg-1 DM and min kg-1 NDF, rumination (min day-1 and min kg-1 DM, and the largest number of mericics chewing per bolus; however, a higher feed efficiency (g DM h-1 was observed in the 30:70 diet group. Furthermore, animals feeding voluntarily had higher DM intake and chewed for longer. Therefore, the combined results indicated that crambe cake could be used in the diet of sheep without affecting feeding behavior.

  17. Utility Interfaced Pulse-Width Modulation of Solar Fed Voltage ...

    African Journals Online (AJOL)

    Utility Interfaced Pulse-Width Modulation of Solar Fed Voltage Source Inverter Using Fixed-Band Hysteresis Current Controller Method. ... with the conversion of solar energy into electrical energy; boosting the dc power; inversion of the dc to ac and then synchronization of the inverter output with the utility, and consequently, ...

  18. Zinc deprivation of methanol fed anaerobic granular sludge bioreactors

    NARCIS (Netherlands)

    Fermoso, F.G.; Collins, G.; Bartacek, J.; Lens, P.N.L.

    2008-01-01

    The effect of omitting zinc from the influent of mesophilic (30 degrees C) methanol fed upflow anaerobic sludge bed (UASB) reactors, and latter zinc supplementation to the influent to counteract the deprivation, was investigated by coupling the UASB reactor performance to the microbial ecology of

  19. Carcass and internal organ characteristics of brioler chickens fed ...

    African Journals Online (AJOL)

    One hundred and forty-four (144) broiler chickens were used to evaluate the carcass and internal organ characteristics of broiler chickens fed soybean diet partially replaced with variable levels of raw jackfruit seed meal (RJFSM). The study lasted for 7 weeks. The inclusion levels of RJFSM were 10, 20 and 30% respectively ...

  20. Testicular morphometry and sperm reserves of local turkey toms fed ...

    African Journals Online (AJOL)

    The morphometry and sperm reserves of the testis, epididymis and vas deferens of three groups (n=5/ group) of sexually active adult local turkey toms fed isocaloric diet with varying levels (12 %, 16 %, 20 %) of protein were studied for sixteen weeks. The weights of the toms before treatment were between 3.5 – 4.5 kg, while ...

  1. Haematology and serum biochemistry of laying hens fed red pepper ...

    African Journals Online (AJOL)

    The hematology and serum biochemistry of ISA brown laying hens fed red pepper (Capsicum annum. L.) as feed additive in their diet was studied. Sixty (60) laying birds (in their 32nd week) were randomly allotted to four different dietary treatments with graded levels of red pepper (Capsicum annum. L.) as additive.

  2. Haemato-biochemistry of Albino rats fed African Kudzu ( Pueraria ...

    African Journals Online (AJOL)

    The effects of cooked and acid-extracted kudzu seed meals on some nutritional and blood and liver biochemical parameters were investigated. Rats fed cooked kudzu meal had significantly (p<0.01) slower rates of growth than the casein control. Cooking enhanced feed efficiency (FE) but the acid-extracted meal could not ...

  3. Biological studies on albino rats fed with Sorghum bicolor starch ...

    African Journals Online (AJOL)

    Partially purified amylase was extracted from the culture medium of Rhizopus sp. grown in potato dextrose broth for 48 h at room temperature by precipitation with 96.9% ethanol. The enzyme was used to hydrolyze sorghum starch. The hydrolyzed product was afterwards formulated into rat feed, which was fed to albino rats ...

  4. Performance and physiological responses of milk-fed calves to ...

    African Journals Online (AJOL)

    CCB) on calf performance and some blood parameters. Sixteen female Holstein calves with a mean age of 3 ± 1 d were divided into two equal groups and fed a milk replacer supplemented with 3 g of coated calcium butyrate (CCB)/day or with no ...

  5. Growth Performance and Hematological Traits of Weaner Pigs Fed ...

    African Journals Online (AJOL)

    BSN

    http://www.ajol.info/index.php/njb/index and ... for their growth and haematological parameters when fed graded levels of raw ... significant (P<0.05) differences among treatments in feed intake, weight gain, ... Keywords: Growth Performance, Bambara nut wastes, Weaner Pigs and ... waste used in the feeding of pigs (Okeke,.

  6. Growth performance and nutrient digestibility of broiler chickens fed ...

    African Journals Online (AJOL)

    Two hundred and seventy (270), day old chicks were used in a completely randomized design experimental layout to test the growth performance and nutrient digestibility of broiler chickens fed single phase diets containing natuzyme™ treated groundnut shell at 0, 5, 10, 15, 20 and 25 % inclusion levels. The treatments ...

  7. Digestive efficiency of indigenous and invasive avian species fed ...

    African Journals Online (AJOL)

    ... Knysna (Tauraco corythaix) and Purple-crested (Gallirex porphyreolophus) Turacos and invasive alien Rose-ringed Parakeets (Psittacula krameri) met their energy demands when fed fruits of four fleshyfruited invasive alien plant species: Solanum mauritianum, Cinnamomum camphora, Psidium guajava and Morus alba.

  8. Haematology and serum chemistry of finisher broiler chickens fed ...

    African Journals Online (AJOL)

    This study was conducted to assess the haematology and serum chemistry of broiler chickens fed maize-cassava diets supplemented with methionine and inorganic sulphur. A total of 270 day-old broiler chicks were randomly assigned to nine treatment groups of 30 birds making 10 birds per replicate group. Starter and ...

  9. Oligosaccharides in feces of breast- and formula-fed babies

    NARCIS (Netherlands)

    Albrecht, S.A.; Schols, H.A.; Zoeren, van D.; Lingen, van R.A.; Groot Jebbink, L.J.M.; Heuvel, van den E.G.H.M.; Voragen, A.G.J.; Gruppen, H.

    2011-01-01

    So far, little is known on the fate of oligosaccharides in the colon of breast- and formula-fed babies. Using capillary electrophoresis with laser induced fluorescence detector coupled to a mass spectrometer (CE–LIF–MSn), we studied the fecal oligosaccharide profiles of 27 two-month-old breast-,

  10. Oligosaccharides in feces of breast- and formula-fed babies.

    Science.gov (United States)

    Albrecht, Simone; Schols, Henk A; van Zoeren, Diny; van Lingen, Richard A; Groot Jebbink, Liesbeth J M; van den Heuvel, Ellen G H M; Voragen, Alphons G J; Gruppen, Harry

    2011-10-18

    So far, little is known on the fate of oligosaccharides in the colon of breast- and formula-fed babies. Using capillary electrophoresis with laser induced fluorescence detector coupled to a mass spectrometer (CE-LIF-MS(n)), we studied the fecal oligosaccharide profiles of 27 two-month-old breast-, formula- and mixed-fed preterm babies. The interpretation of the complex oligosaccharide profiles was facilitated by beforehand clustering the CE-LIF data points by agglomerative hierarchical clustering (AHC). In the feces of breast-fed babies, characteristic human milk oligosaccharide (HMO) profiles, showing genetic fingerprints known for human milk of secretors and non-secretors, were recognized. Alternatively, advanced degradation and bioconversion of HMOs, resulting in an accumulation of acidic HMOs or HMO bioconversion products was observed. Independent of the prebiotic supplementation of the formula with galactooligosaccharides (GOS) at the level used, similar oligosaccharide profiles of low peak abundance were obtained for formula-fed babies. Feeding influences the presence of diet-related oligosaccharides in baby feces and gastrointestinal adaptation plays an important role herein. Four fecal oligosaccharides, characterized as HexNAc-Hex-Hex, Hex-[Fuc]-HexNAc-Hex, HexNAc-[Fuc]-Hex-Hex and HexNAc-[Fuc]-Hex-HexNAc-Hex-Hex, highlighted an active gastrointestinal metabolization of the feeding-related oligosaccharides. Their presence was linked to the gastrointestinal mucus layer and the blood-group determinant oligosaccharides therein, which are characteristic for the host's genotype. Copyright © 2011 Elsevier Ltd. All rights reserved.

  11. Fed and fasted state gastro-intestinal in vitro lipolysis

    DEFF Research Database (Denmark)

    Christophersen, Philip Carsten B; Christiansen, Martin Lau; Holm, Rene

    2014-01-01

    The present study aims at evaluating the ability of a gastro-intestinal in vitro lipolysis model to predict the performance of two lipid formulations and a conventional tablet containing a poorly soluble drug, cinnarizine, in dogs, both in the fasted and fed state. A self-nano-emulsifying drug de...

  12. Reproductive performance of female goats fed life-enzyme ...

    African Journals Online (AJOL)

    Direct-fed-microbes (DFM) (life-enzyme) was prepared in a traditional setting using Zymomonas mobilis (bacteria from palm sap) to ferment sawdust. The result revealed an improvement in the nutrient content of the sawdust and its feed values (protein, fibre etc.), and the feed usage efficiency. The reproductive ...

  13. Performance of growing Yankasa rams Fed graded levels of ...

    African Journals Online (AJOL)

    SH

    The experimental diets formulated were A (0%), B (15%) and C (30%) inclusion levels of the test ingredient. ... experiment, the experimental animals were dewormed with Albendazole at 1ml per. 50kg body weight and fed with the experimental diets. The experimental animals were .... 34th annual conference of the NSAP.

  14. Performance of West African Dwarf Goats fed maize stover based ...

    African Journals Online (AJOL)

    The study was carried out to investigate the effect of exogenous fibrolytic enzyme additive (containing cellulase, xylanase and beta glucanase) on the growth performance and nutrient digestibility parameters of West African dwarf (WAD) goats fed total mixed ration in the dry season. A total of sixteen (16) WAD goats were ...

  15. Nutrient digestibility and egg production of laying hens fed graded ...

    African Journals Online (AJOL)

    A 20-week feeding trial involving 72 Isa brown-laying birds, in a completely randomized design, evaluated the nutrient digestibility and egg production of layers fed diets containing biodegraded palm kernel meal (PKM) at dietary levels of 20 per cent undegraded and 20, 30 and 40 per cent biodegraded PKM, respectively.

  16. Performance and economy of production of laying hens fed graded ...

    African Journals Online (AJOL)

    Experiments were carried out to evaluate the performance of laying hens fed fermented wild cocoyam corm (FWCC) as a partial replacement for maize. Two hundred and forty (240) Nera black laying birds were randomly allocated to four experimental diets formulated on 0, 10, 20 and 30% FWCC as graded replacement ...

  17. Low serum biotin in Japanese children fed with hydrolysate formula.

    Science.gov (United States)

    Sato, Yasuhiro; Wakabayashi, Kenji; Ogawa, Eishin; Kodama, Hiroko; Mimaki, Masakazu

    2016-09-01

    Given that nutritional biotin deficiency in Japanese infants has been reported, a straightforward method for estimating biotin level is needed. The biotin content in infant formula, breast milk, and the sera of infants fed with various types of formula were measured using avidin-binding assay. A commercially available ELISA kit was used for the measurement of biotin in 54 types of formula, including hydrolysate formulas for milk allergy, as well as in breast milk and in the sera of 27 infants fed with these formulas. The biotin content reached the recommended value in only five formulas. All of the hydrolysate formulas and more than half of the special formulas contained biotin biotin was low in infants fed only with the hydrolysate formulas, and one of them had alopecia related to biotin deficiency. While many were asymptomatic, infants fed with formulas lacking biotin are at risk of developing symptomatic disease. The addition of biotin to breast milk substitutes was finally approved in the middle of 2014, however pediatricians in Japan should still be vigilant with regard to nutritional biotin deficiency in infants for the time being. © 2016 Japan Pediatric Society.

  18. Semen characteristics of pubertal Yankasa rams fed Zingiber ...

    African Journals Online (AJOL)

    Ginger (Zingiber officinale) is consumed by humans and has been reported to possess medicinal uses. It possesses androgenic property with significant increase on male reproductive parameters. This study assessed the reproductive performance of Yankasa rams fed diets supplemented with different levels of ginger ...

  19. Performance response and egg qualities of laying birds fed enzyme ...

    African Journals Online (AJOL)

    Theperformance response and egg qualities o laying birds fed enzyme supplemented PKC diets asreplacement for maize was investigated wth 210, 20 week old layng pullets of Dominant Black strain at the Teaching and Research Farm of the Delta State University, Asaba Campus, Nigeria. The birds which ust come into ...

  20. Performance of Sahiwal and Friesian heifers fed on napier grass

    African Journals Online (AJOL)

    fed on napier grass (Pennisetum purpureum) which has been adopted owing to its high dry matter. (DM) yields and palatability (Anindo ... high nutrient yields and therefore high animal output are likely to be achieved. Unfortunately, farm- ers lack specific ..... This consequently led to higher nutrient intake and weight gains.

  1. Nutritive value and biochemical changes in broiler chickens fed ...

    African Journals Online (AJOL)

    Castor bean (Ricinus communis Linn.) is an important oilseed rich in protein but rarely used as livestock feed due to antinutritional factors. Castor seed was detoxified using combined processing techniques of moist heating and fermentation (5 and 7- day) or lye treatment and fed to150 day-old Anak 2000 broiler chicks at ...

  2. Doubly-Fed Induction Generator Control Under Voltage Sags

    DEFF Research Database (Denmark)

    Teodorescu, Remus; Blaabjerg, Frede; Lima, K.

    2008-01-01

    This paper proposes a new control technique to improve the fault-ride through capability of doubly fed induction generators (DFIG). In such generators the appearance of severe voltage sags at the coupling point make rise to high over currents at the rotor/stator windings, something that makes...

  3. Effect of Different Levels of Molasses Fed Through Drinking Water ...

    African Journals Online (AJOL)

    An experiment was conducted to evaluate the effect of molasses fed through drinking water on growth and economic performance of broiler chickens. One hundred and sixty unsexed day old chicks of Anak strain were used. They were divided into four treatment groups with each group having four replicates of ten birds per ...

  4. Energy partitioning for growth by rabbits fed groundnut and stylo ...

    African Journals Online (AJOL)

    Forty eight crossbred (California X New Zealand White) rabbits were used to evaluate energy partitioning of rabbits fed forages supplemented with concentrate. The rabbits were randomly allocated to three treatments consisting of sole Stylosanthes hamata (stylo),sole Arachis hypogea (groundnut) haulms and 50:50 mixture ...

  5. A Current-Fed Isolated Bidirectional DC-DC Converter

    DEFF Research Database (Denmark)

    Sun, Xiaofeng; Wu, Xiaoying; Shen, Yanfeng

    2017-01-01

    This paper proposes a current-fed isolated bidirectional DC-DC converter (CF-IBDC) which has the advantages of wide input voltage range, low input current ripple, low conduction losses, and soft switching over the full operating range. Compared with conventional CF-IBDCs, the voltage spikes...

  6. Growth and Survival of Catfish ( Clarias anguillaris ) Juveniles Fed ...

    African Journals Online (AJOL)

    Juveniles of catfish, Clarias anguillaris (mean weight, 119.8g) were fed unconventional diets for ten weeks in outdoor hapas (net cages, 1m3 dimension) and the growth responses and feed utilization by the juveniles were compared. The experimental diets were (i) live maggots, (ii) live tilapia fry, (iii) commercial catfish feed ...

  7. Reproductive indices of Merino rams fed sun-cured Leucaena ...

    African Journals Online (AJOL)

    Reproductive indices of Merino rams fed sun-cured Leucaena leucocephala forage. I.V. Nsahlai, B.K. Byebwa, M.L.K. Bonsi. Abstract. (South African J of Animal Science, 2000, 30, Supplement 1: 111-112). Full Text: EMAIL FREE FULL TEXT EMAIL FREE FULL TEXT · DOWNLOAD FULL TEXT DOWNLOAD FULL TEXT.

  8. Antioxidant status and serology of laying pullets fed diets ...

    African Journals Online (AJOL)

    Sixty (60) eighteen weeks old ISA Brown pullets were randomly allocated to four dietary treatments when egg production was 4% in a completely randomized design. The birds ... Pullets fed mistletoe leaf meal had significantly (p<0.05) lower serum cholesterol and low density lipoprotein compared to the control. Serum ...

  9. Performance of rabbits fed Leucaena leucocephala and concentrate ...

    African Journals Online (AJOL)

    Four fryers which were fed the same % of concentrates and Aspilia africana served as the control. Growth rate decreased at the beginning of the study followed by satisfactory growth thereafter. The control animals had a higher growth rate compared to the other two groups (P< 0.05). Alopecia and decreased appetite were ...

  10. Control of variable speed wind turbine with doubly-fed induction generator

    Energy Technology Data Exchange (ETDEWEB)

    Hansen, A.D.; Soerensen, P. [Risoe National Lab., Wind Energy Dept., Roskilde (Denmark); Iov, F.; Blaabjerg, F. [Aalborg Univ., Inst. of Energy Technology, Aalborg (Denmark)

    2004-07-01

    draIn this paper, a Control method suitable for a variable speed grid connected pitch-controlled wind turbine with doubly-fed induction generator (DFIG) is developed. The targets of the Control system are: 1) to Control the power drawn from the wind turbine in order to track the wind turbine optimum operation point 2) to limit the power in case of high wind speeds and 3) to Control the reactive power interchanged between the wind turbine generator and the grid. The considered configuration of DFIG is an induction generator with a wound rotor connected to the grid through a back-to-back power converter and a stator directly connected to the grid. The paper presents the overall Control system of the variable speed DFIG wind turbine, with focus on the Control strategies and algorithms applied at each hierarchical Control level of the wind turbine. There are two Control levels: a DFIG Control level and wind turbine Control level. The DFIG Control level contains a fast Control of the power converter and of the doubly-fed induction generator and it has as goal to Control the active and reactive power of the wind turbine independently. The wind turbine Control level supervises with Control signals both the DFIG Control level and the hydraulic pitch Control system of the wind turbine. The present Control method is designed for normal continuous operations. The variable speed/variable pitch wind turbine with doubly-fed induction generator is implemented in the dynamic power system simulation tool DIgSILENT, which makes possible to investigate the dynamic performance of gid-connected wind turbines as a part of realistic electrical grid models. Several significant simulation results are performed With the overall Control-implemented algorithm applied on a variable speed, variable pitch wind turbine model. (au)

  11. Dynamic participation of doubly fed induction generator in automatic generation control

    Energy Technology Data Exchange (ETDEWEB)

    Bhatt, Praghnesh [Department of Electrical Engineering, Charotar Institute of Technology, Changa, Gujarat-388421 (India); Roy, Ranjit [Department of Electrical Engineering, S.V. National Institute of Technology, Surat, Gujarat-395007 (India); Ghoshal, S.P. [Department of Electrical Engineering, National Institute of Technology, Durgapur, West Bengal-713209 (India)

    2011-04-15

    Increasing levels of wind generation have resulted in an urgent need for the assessment of their impact on frequency control of power systems. The displacement of conventional generation with wind generation will result in erosion of system frequency. The paper analyzed the dynamic participation of doubly fed induction generator (DFIG) to system frequency responses of two-area interconnected power system having variety of conventional generating units. Frequency control support function responding proportionally to frequency deviation is proposed to take out the kinetic energy of turbine blades in order to improve the frequency response of the system. Impacts of different wind penetrations in the system and varying active power support from wind farm on frequency control have been investigated. Integral gains of AGC loop are optimized through craziness-based particle swarm optimization (CRPSO) in order to have optimal transient responses of area frequencies, tie-line power deviation and DFIG parameters. (author)

  12. Intestinal mucosa development in broiler chickens fed natural growth promoters

    Directory of Open Access Journals (Sweden)

    ERL Pelicano

    2005-12-01

    Full Text Available This study evaluated the use of probiotics and prebiotics on the histological and morphological indexes of the intestinal mucosa of broilers at 21 days of age. Thirty-six birds were randomly distributed in a 3 x 3 factorial arrangement, considering 3 probiotics and prebiotics sources in the diet. There were 9 treatments with 4 repetitions. Diet treatments were: 1 - Control (without growth promoters; 2 - Bacillus subtilis-based probiotic (Pro 1; 3 - Probiotic (Pool based on Lactobacillus acidophilus and casei, Streptococcus lactis and faecium, Bifidobacterium bifidum and Aspergillus oryzae (Pro 2; 4 - Prebiotic based on Phosphorylated Mannanoligosaccharide (MOS and Organic Acidifier (OA (Pre 1; 5 - MOS-based prebiotic (Pre 2; 6 - Pro 1 + Pre 1; 7 - Pro 1 + Pre 2; 8 - Pro 2 + Pre 1; 9 - Pro 2 + Pre 2. Higher villus height (VH (p<0.01 were seen in the duodenum of birds fed diets without prebiotics, whereas birds fed Bacillus subtilis-based probiotic and birds fed prebiotic based on MOS and OA showed higher VH (p<0.01 in jejunum and ileum. Greater crypt depths (CD (p<0.01 were observed in the duodenum, jejunum and ileum of birds receiving B. subtilis, and in the duodenum and jejunum of birds fed diets without prebiotics. Significant interaction (p<0.01 between the evaluated factors was seen for both, VH and CD, in the three intestinal portions. Greater VH was obtained in duodenum, jejunum and ileum with the use of probiotics and prebiotics and greater CD with the use of probiotics, in relation to the control group. There was no difference in villus density (VD between birds fed diets without additives or diets containing probiotics and prebiotics. Nevertheless, there was a significant interaction (p<0.05 between the evaluated factors for VD in the duodenum. Concluding, beneficial effects were seen in histological indexes of the intestinal mucosa with the use of probiotics and prebiotics at 21 days of age.

  13. The Physics of Wind-Fed Accretion

    International Nuclear Information System (INIS)

    Mauche, Christopher W.; Liedahl, Duane A.; Akiyama, Shizuka; Plewa, Tomasz

    2008-01-01

    We provide a brief review of the physical processes behind the radiative driving of the winds of OB stars and the Bondi-Hoyle-Lyttleton capture and accretion of a fraction of the stellar wind by a compact object, typically a neutron star, in detached high-mass X-ray binaries (HMXBs). In addition, we describe a program to develop global models of the radiatively-driven photoionized winds and accretion flows of HMXBs, with particular attention to the prototypical system Vela X-l. The models combine XSTAR photoionization calculations, HULLAC emission models appropriate to X-ray photoionized plasmas, improved models of the radiative driving of photoionized winds, FLASH time-dependent adaptive-mesh hydrodynamics calculations, and Monte Carlo radiation transport. We present two- and three-dimensional maps of the density, temperature, velocity, ionization parameter, and emissivity distributions of representative X-ray emission lines, as well as synthetic global Monte Carlo X-ray spectra. Such models help to better constrain the properties of the winds of HMXBs, which bear on such fundamental questions as the long-term evolution of these binaries and the chemical enrichment of the interstellar medium.

  14. Environmental impacts of irrigated and rain-fed barley production in Iran using life cycle assessment (LCA)

    Energy Technology Data Exchange (ETDEWEB)

    Houshyar, E.

    2017-07-01

    Current intensive grain crops production is often associated with environmental burdens. However, very few studies deal with the environmental performance of both current and alternative systems of barley production. This study was undertaken to evaluate energy consumption and environmental impacts of irrigated and rain-fed barley production. Additionally, three alternative scenarios were examined for irrigated barley fields including conservation tillage and biomass utilization policies. The findings showed that around 25 GJ/ha energy is needed in order to produce 2300 kg/ha irrigated barley and 13 GJ/ha for 1100 kg/ha rain-fed barley. Life cycle assessment (LCA) results indicated that irrigated farms had more environmental impacts than rain-fed farms. Electricity generation and consumption had the highest effect on the abiotic depletion potential, human toxicity potential, freshwater and marine aquatic ecotoxicity potential. However, alternative scenarios revealed that using soil conservation tillage systems and biomass consumption vs. gas for electricity generation at power plants can significantly mitigate environmental impacts of irrigated barley production similar to the rain-fed conditions while higher yield is obtained.

  15. Environmental impacts of irrigated and rain-fed barley production in Iran using life cycle assessment (LCA)

    International Nuclear Information System (INIS)

    Houshyar, E.

    2017-01-01

    Current intensive grain crops production is often associated with environmental burdens. However, very few studies deal with the environmental performance of both current and alternative systems of barley production. This study was undertaken to evaluate energy consumption and environmental impacts of irrigated and rain-fed barley production. Additionally, three alternative scenarios were examined for irrigated barley fields including conservation tillage and biomass utilization policies. The findings showed that around 25 GJ/ha energy is needed in order to produce 2300 kg/ha irrigated barley and 13 GJ/ha for 1100 kg/ha rain-fed barley. Life cycle assessment (LCA) results indicated that irrigated farms had more environmental impacts than rain-fed farms. Electricity generation and consumption had the highest effect on the abiotic depletion potential, human toxicity potential, freshwater and marine aquatic ecotoxicity potential. However, alternative scenarios revealed that using soil conservation tillage systems and biomass consumption vs. gas for electricity generation at power plants can significantly mitigate environmental impacts of irrigated barley production similar to the rain-fed conditions while higher yield is obtained.

  16. Tritium-management requirements for D-T fusion reactors (ETF, INTOR, FED)

    International Nuclear Information System (INIS)

    Finn, P.A.; Clemmer, R.G.; Misra, B.

    1981-10-01

    The successful operation of D-T fusion reactors will depend on the development of safe and reliable tritium-containment and fuel-recycle systems. The tritium handling requirements for D-T reactors were analyzed. The reactor facility was then designed from the viewpoint of tritium management. Recovery scenarios after a tritium release were generated to show the relative importance of various scenarios. A fusion-reactor tritium facility was designed which would be appropriate for all types of plants from the Engineering Test Facility (ETF), the International Tokamak Reactor (INTOR), and the Fusion Engineering Device (FED) to the full-scale power plant epitomized by the STARFIRE design

  17. PIBAS FedSPARQL: a web-based platform for integration and exploration of bioinformatics datasets.

    Science.gov (United States)

    Djokic-Petrovic, Marija; Cvjetkovic, Vladimir; Yang, Jeremy; Zivanovic, Marko; Wild, David J

    2017-09-20

    There are a huge variety of data sources relevant to chemical, biological and pharmacological research, but these data sources are highly siloed and cannot be queried together in a straightforward way. Semantic technologies offer the ability to create links and mappings across datasets and manage them as a single, linked network so that searching can be carried out across datasets, independently of the source. We have developed an application called PIBAS FedSPARQL that uses semantic technologies to allow researchers to carry out such searching across a vast array of data sources. PIBAS FedSPARQL is a web-based query builder and result set visualizer of bioinformatics data. As an advanced feature, our system can detect similar data items identified by different Uniform Resource Identifiers (URIs), using a text-mining algorithm based on the processing of named entities to be used in Vector Space Model and Cosine Similarity Measures. According to our knowledge, PIBAS FedSPARQL was unique among the systems that we found in that it allows detecting of similar data items. As a query builder, our system allows researchers to intuitively construct and run Federated SPARQL queries across multiple data sources, including global initiatives, such as Bio2RDF, Chem2Bio2RDF, EMBL-EBI, and one local initiative called CPCTAS, as well as additional user-specified data source. From the input topic, subtopic, template and keyword, a corresponding initial Federated SPARQL query is created and executed. Based on the data obtained, end users have the ability to choose the most appropriate data sources in their area of interest and exploit their Resource Description Framework (RDF) structure, which allows users to select certain properties of data to enhance query results. The developed system is flexible and allows intuitive creation and execution of queries for an extensive range of bioinformatics topics. Also, the novel "similar data items detection" algorithm can be particularly

  18. Sensorless direct voltage control of the stand-alone brushless doubly-fed generator

    DEFF Research Database (Denmark)

    Liu, Yi; Xu, Wei; Xiong, Fei

    2017-01-01

    The conventional stand-alone brushless doubly-fed generator (BDFG) control strategies need the feedback from the rotor position or speed sensors, which can reduce system reliability and increase the cost and axial volume of the machine. In this paper, a sensorless direct voltage control (DVC) str......) strategy is presented for the stand-alone BDFG. The satisfactory dynamic performance is verified by experimental results under four kinds of typical operation conditions. Besides, the proposed control strategy is robust due to no generator parameters being required....

  19. Optimal Control of a Fed-Batch Fermentation Involving Multiple Feeds

    Directory of Open Access Journals (Sweden)

    Chongyang Liu

    2012-01-01

    Full Text Available A nonlinear dynamical system, in which the feed rates of glycerol and alkali are taken as the control functions, is first proposed to formulate the fed-batch culture of 1,3-propanediol (1,3-PD production. To maximize the 1,3-PD concentration at the terminal time, a constrained optimal control model is then presented. A solution approach is developed to seek the optimal feed rates based on control vector parametrization method and improved differential evolution algorithm. The proposed methodology yielded an increase by 32.17% of 1,3-PD concentration at the terminal time.

  20. Equipment experience in a radioactive LFCM [liquid-fed ceramic melter] vitrification facility

    International Nuclear Information System (INIS)

    Holton, L.K. Jr.; Dierks, R.D.; Sevigny, G.J.; Goles, R.W.; Surma, J.E.; Thomas, N.M.

    1986-11-01

    Since October 1984, the Pacific Northwest Laboratory (PNL) has operated a pilot-scale radioactive liquid-fed ceramic melter (RLFCM) vitrification process in shielded manipulator hot cells. This vitrification facility is being operated for the Department of Energy (DOE) to remotely test vitrification equipment components in a radioactive environment and to develop design and operation data that can be applied to production-scale projects. This paper summarizes equipment and process experience obtained from the operations of equipment systems for waste feeding, waste vitrification, canister filling, canister handling, and vitrification off-gas treatment

  1. A new soft switched push pull current fed converter for fuel cell applications

    International Nuclear Information System (INIS)

    Delshad, Majid; Farzanehfard, Hosein

    2011-01-01

    In this paper a new zero voltage switching current fed push pull dc-dc converter is proposed for fuel cell generation system. The auxiliary circuit in this converter, not only absorbs the voltage surge across the switches at turn off instance, but also provides zero voltage switching condition for all converter switches. Therefore, the converter efficiency is increased and size and weight of the converter can be decreased. Also implementation of control circuit is very simple since the converter is PWM controlled. In this paper, the proposed dc-dc converter operating modes are analyzed and to verify the converter operation a laboratory prototype is implemented and the experimental results are presented.

  2. Beam-Steerable Microstrip-Fed Bow-Tie Antenna Array for Fifth Generation Cellular Communications

    DEFF Research Database (Denmark)

    Ojaroudiparchin, Naser; Shen, Ming; Pedersen, Gert Frølund

    2016-01-01

    The design and performance of mm-wave phased array antenna for 5G mobile broadband communication systems has been provided in this manuscript. The antenna is designed on a N9000 PTFE substrate with 0.787 mm thickness and 2.2 dielectric constant and 65×130 mm2 overall dimension. Eight elements...... of bow-tie antennas have been used at the top-edge region of mobile phone PCB. The antenna elements fed by microstrip lines are designed to operate at 17 GHz. The simulated results give good performances in terms of different antenna parameters. In addition, an investigation on the distance between...

  3. Centralised power control of wind farm with doubly fed induction generators

    DEFF Research Database (Denmark)

    Hansen, A.D.; Sørensen, Poul Ejnar; Iov, F.

    2006-01-01

    At the moment, the control ability of wind farms is a prime research concern for the grid integration of large wind farms, due to their required active role in the power system. This paper describes the on-going work of a research project, whose overall objective is to analyse and assess...... the possibilities for control of different wind farm concepts. The scope of this paper is the control of a wind farm made up exclusively of doubly fed induction generators. The paper addresses the design and implementation issues of such a controller and focuses on the ability of the wind farm control strategy...

  4. Comparison of control strategies for Doubly fed induction generator under recurring grid faults

    DEFF Research Database (Denmark)

    Chen, Wenjie; Blaabjerg, Frede; Zhu, Nan

    2014-01-01

    The new grid codes demand the wind turbine systems to ride through recurring grid faults. Many control strategies have been proposed for the Doubly Fed Induction Generator under single grid fault, but their performance under recurring grid faults have not been studied yet. In this paper, five...... different control strategies for DFIG to ride through single grid faults are presented, and their performance under recurring grid faults are analyzed. The controllable range, stator time constant and torque fluctuations of the DFIG with different control strategies are compared. The results are verified...

  5. Efficient solar-to-fuels production from a hybrid microbial-water-splitting catalyst system.

    Science.gov (United States)

    Torella, Joseph P; Gagliardi, Christopher J; Chen, Janice S; Bediako, D Kwabena; Colón, Brendan; Way, Jeffery C; Silver, Pamela A; Nocera, Daniel G

    2015-02-24

    Photovoltaic cells have considerable potential to satisfy future renewable-energy needs, but efficient and scalable methods of storing the intermittent electricity they produce are required for the large-scale implementation of solar energy. Current solar-to-fuels storage cycles based on water splitting produce hydrogen and oxygen, which are attractive fuels in principle but confront practical limitations from the current energy infrastructure that is based on liquid fuels. In this work, we report the development of a scalable, integrated bioelectrochemical system in which the bacterium Ralstonia eutropha is used to efficiently convert CO2, along with H2 and O2 produced from water splitting, into biomass and fusel alcohols. Water-splitting catalysis was performed using catalysts that are made of earth-abundant metals and enable low overpotential water splitting. In this integrated setup, equivalent solar-to-biomass yields of up to 3.2% of the thermodynamic maximum exceed that of most terrestrial plants. Moreover, engineering of R. eutropha enabled production of the fusel alcohol isopropanol at up to 216 mg/L, the highest bioelectrochemical fuel yield yet reported by >300%. This work demonstrates that catalysts of biotic and abiotic origin can be interfaced to achieve challenging chemical energy-to-fuels transformations.

  6. Efficient solar-to-fuels production from a hybrid microbial–water-splitting catalyst system

    Science.gov (United States)

    Torella, Joseph P.; Gagliardi, Christopher J.; Chen, Janice S.; Bediako, D. Kwabena; Colón, Brendan; Way, Jeffery C.; Silver, Pamela A.; Nocera, Daniel G.

    2015-01-01

    Photovoltaic cells have considerable potential to satisfy future renewable-energy needs, but efficient and scalable methods of storing the intermittent electricity they produce are required for the large-scale implementation of solar energy. Current solar-to-fuels storage cycles based on water splitting produce hydrogen and oxygen, which are attractive fuels in principle but confront practical limitations from the current energy infrastructure that is based on liquid fuels. In this work, we report the development of a scalable, integrated bioelectrochemical system in which the bacterium Ralstonia eutropha is used to efficiently convert CO2, along with H2 and O2 produced from water splitting, into biomass and fusel alcohols. Water-splitting catalysis was performed using catalysts that are made of earth-abundant metals and enable low overpotential water splitting. In this integrated setup, equivalent solar-to-biomass yields of up to 3.2% of the thermodynamic maximum exceed that of most terrestrial plants. Moreover, engineering of R. eutropha enabled production of the fusel alcohol isopropanol at up to 216 mg/L, the highest bioelectrochemical fuel yield yet reported by >300%. This work demonstrates that catalysts of biotic and abiotic origin can be interfaced to achieve challenging chemical energy-to-fuels transformations. PMID:25675518

  7. Effect of forage quality in faeces from different ruminant species fed high and low quality forage

    DEFF Research Database (Denmark)

    Jalali, A R; Nørgaard, P; Nielsen, M O

    2010-01-01

    Effect of forage quality in faeces from different ruminant species fed high and low quality forage......Effect of forage quality in faeces from different ruminant species fed high and low quality forage...

  8. State reference design and saturated control of doubly-fed induction generators under voltage dips

    Science.gov (United States)

    Tilli, Andrea; Conficoni, Christian; Hashemi, Ahmad

    2017-04-01

    In this paper, the stator/rotor currents control problem of doubly-fed induction generator under faulty line voltage is carried out. Common grid faults cause a steep decline in the line voltage profile, commonly denoted as voltage dip. This point is critical for such kind of machines, having their stator windings directly connected to the grid. In this respect, solid methodological nonlinear control theory arguments are exploited and applied to design a novel controller, whose main goal is to improve the system behaviour during voltage dips, endowing it with low voltage ride through capability, a fundamental feature required by modern Grid Codes. The proposed solution exploits both feedforward and feedback actions. The feedforward part relies on suitable reference trajectories for the system internal dynamics, which are designed to prevent large oscillations in the rotor currents and command voltages, excited by line perturbations. The feedback part uses state measurements and is designed according to Linear Matrix Inequalities (LMI) based saturated control techniques to further reduce oscillations, while explicitly accounting for the system constraints. Numerical simulations verify the benefits of the internal dynamics trajectory planning, and the saturated state feedback action, in crucially improving the Doubly-Fed Induction Machine response under severe grid faults.

  9. Active Power Optimal Control of Wind Turbines with Doubly Fed Inductive Generators Based on Model Predictive Control

    Directory of Open Access Journals (Sweden)

    Guo Jiuwang

    2015-01-01

    Full Text Available Because of the randomness and fluctuation of wind energy, as well as the impact of strongly nonlinear characteristic of variable speed constant frequency (VSCF wind power generation system with doubly fed induction generators (DFIG, traditional active power control strategies are difficult to achieve high precision control and the output power of wind turbines is more fluctuated. In order to improve the quality of output electric energy of doubly fed wind turbines, on the basis of analyzing the operating principles and dynamic characteristics of doubly fed wind turbines, this paper proposes a new active power optimal control method of doubly fed wind turbines based on predictive control theory. This method uses state space model of wind turbines, based on the prediction of the future state of wind turbines, moves horizon optimization, and meanwhile, gets the control signals of pitch angle and generator torque. Simulation results show that the proposed control strategies can guarantee the utilization efficiency for wind energy. Simultaneously, they can improve operation stability of wind turbines and the quality of electric energy.

  10. Forskolin- and dihydroalprenolol (DHA) binding sites and adenylate cyclase activity in heart of rats fed diets containing different oils

    International Nuclear Information System (INIS)

    Alam, S.Q.; Ren, Y.F.; Alam, B.S.

    1987-01-01

    The purpose of the present investigation was to determine if dietary lipids can induce changes in the adenylate cyclase system in rat heart. Three groups of male young Sprague-Dawley rats were fed for 6 weeks diets containing 10% corn oil (I), 8% coconut oil + 2% corn oil (II) or 10% menhaden oil (III). Adenylate cyclase activity (basal, fluoride-, isoproterenol-, and forskolin-stimulated) was higher in heart homogenates of rats in group III than in the other two groups. Concentration of the [ 3 H]-forskolin binding sites in the cardiac membranes were significantly higher in rats fed menhaden oil. The values (pmol/mg protein) were 4.8 +/- 0.2 (I), 4.5 +/- 0.7 (II) and 8.4 +/- 0.5 (III). There was no significant difference in the affinity of the forskolin binding sites among the 3 dietary groups. When measured at different concentrations of forskolin, the adenylate cyclase activity in cardiac membranes of rats fed menhaden oil was higher than in the other 2 groups. Concentrations of the [ 3 H]DHA binding sites were slightly higher but their affinity was lower in cardiac membranes of rats fed menhaden oil. The results suggest that diets containing fish oil increase the concentration of the forskolin binding sites and may also affect the characteristics of the β-adrenergic receptor in rat heart

  11. Reproduction in eastern screech-owls fed selenium

    Science.gov (United States)

    Wiemeyer, Stanley N.; Hoffman, D.J.

    1996-01-01

    Raptors are occasionally exposed to excessive selenium from contaminated prey, but the effects of this exposure on reproduction are unknown. Therefore, we fed captive eastern screech-owls (Otus asio) diets containing 0, 4.4, or 13.2 ppm (wet wt) added selenium in the form of seleno-DL-methionine. Adult mass at sacrifice and reproductive success of birds receiving 13.2 ppm selenium were depressed (P biochemistries indicative of oxidative stress were affected (P < 0.05) in 5-day-old nestlings from parents fed 4.4 ppm selenium and included a 19% increase in glutathione peroxidase activity, a 43% increase in the ratio of oxidized glutathione (GSSG) to reduced glutathione (GSH), and a 17% increase in lipid peroxidation. Based on reproductive effects relative to dietary exposure, sensitivity of eastern screech-owls to selenium was similar to that of black-crowned night-herons (Nycticorax nycticorax) but less than that of mallards (Anas platyrhynchos).

  12. Meat characteristics of buffaloes fed with different roughage: concentrate ratios

    Directory of Open Access Journals (Sweden)

    N. Sanghuayprai

    2010-02-01

    Full Text Available Meat characteristics of mature swamp buffalo fed with two different ratios of roughage and concentrate feed was studied. Twelve draught buffaloes with an average weight of 350 kg were randomly divided into two treatments and kept individually in pens. The concentrate:roughage ratio (based on dry matter was 50:50 (T1 or 30:70 (T2, respectively. All buffaloes were slaughtered at a body weight of 500 kg (± 25 and M. longissimus dorsi was removed in order to study meat quality. The meat quality in terms of color, pH and conductivity values were not significantly different between the groups. Meat color in terms of L* (lightness showed that LD of T2 group was significantly lighter when compared with T1 (P0.05. In conclusion, meat characteristic traits of buffalo fed concentrate to roughage in ratios of 50:50 or 30:70 were similar.

  13. Nutrient intake, digestibility and rumen metabolites in bulls fed rice ...

    African Journals Online (AJOL)

    Nutrient intake, digestibility and rumen metabolites were determined in rumen - cannulated bulls fed rice straw or straw supplemented with urea, groundnut hay or cotton seed cake. Total dry matter intake (DMI) ranged from 7.55 Lo 8.29kg/d or 3.66 to 4.04% of liveweight and from 6.48 to 7. 21 kg/d for organic matter.

  14. Ultra-Wideband Coplanar-Fed Monopoles: A Comparative Study

    Directory of Open Access Journals (Sweden)

    J. Jilkova

    2008-04-01

    Full Text Available The paper provides an experimental comparison of four types of ultra-wideband coplanar-fed planar monopole antennas. Parameters of the open stub completed by an L-shaped monopole and the cross monopole were adopted from the literature. The forked monopole and the coplanar monopole were fabricated and measured. Monopoles were compared from the viewpoint of the impedance bandwidth, gain, directivity patterns and dimensions.

  15. Organochlorine compounds in breast-fed vs. bottle-fed infants: preliminary results at six weeks of age

    International Nuclear Information System (INIS)

    Lackmann, G.-M.; Schaller, K.-H.; Angerer, J.

    2004-01-01

    Background: Polychlorinated biphenyls (PCBs), hexachlorobenzene (HCB), and 1,1,1-trichloro-2,2-bis(p-chlorophenyl)ethane (DDT) are ubiquitous compounds with carcinogenic and teratogenic properties. They are chemically very stable and lipophilic and, therefore, accumulate in our food-chain. They are prenatally transmitted from mother to foetus, and mother's milk due to its high lipid content is an elimination pathway of special importance. Therefore, breast-feeding has been held responsible for elevated concentrations of these organochlorine compounds as well as for harmful effects in children later in life. Methods: Blood samples (2.5 ml) were taken from each 10 breast-fed and bottle-fed infants at 6 weeks of age. Blood specimens were immediately centrifuged, and serum was stored in glass tubes at -20 degree sign C until analysis. Three higher chlorinated PCB congeners (IUPAC nos. 138, 153 and 180), HCB, and the organic metabolite of DDT, p,p<<-DDE, were analysed with capillary gas chromatography with electron capture detection. Reliability was tested with gas chromatography-mass spectrometry. Results: There were no differences between the study groups of breast-fed and bottle-fed infants with regard to sex distribution, gestational age, birth-weight, age of the mothers, and smoking behaviour of the parents. In contrast, serum concentrations of all organochlorine compounds were significantly higher (P<0.0001) in breast-fed than in bottle-fed infants (mean): PCB 138, 0.38 vs. 0.10 μg/l; PCB 153, 0.49 vs. 0.1 μg/l; PCB 180, 0.31 vs. 0.04 μg/l; ΣPCB, 1.19 vs. 0.29 μg/l; HCB, 0.13 vs. 0.04 μg/l; p,p<<-DDE, 1.05 vs. 0.18 μg/l. Conclusions: Breast-feeding significantly increases the pollution of our infants with different organochlorine compounds as early as at 6 weeks of age. The progress of the present study will show whether this pollution will further increase with longer duration of breast-feeding, and whether breast-feeding bears any health risks for our

  16. Organochlorine compounds in breast-fed vs. bottle-fed infants: preliminary results at six weeks of age

    Energy Technology Data Exchange (ETDEWEB)

    Lackmann, G.-M.; Schaller, K.-H.; Angerer, J

    2004-08-15

    Background: Polychlorinated biphenyls (PCBs), hexachlorobenzene (HCB), and 1,1,1-trichloro-2,2-bis(p-chlorophenyl)ethane (DDT) are ubiquitous compounds with carcinogenic and teratogenic properties. They are chemically very stable and lipophilic and, therefore, accumulate in our food-chain. They are prenatally transmitted from mother to foetus, and mother's milk due to its high lipid content is an elimination pathway of special importance. Therefore, breast-feeding has been held responsible for elevated concentrations of these organochlorine compounds as well as for harmful effects in children later in life. Methods: Blood samples (2.5 ml) were taken from each 10 breast-fed and bottle-fed infants at 6 weeks of age. Blood specimens were immediately centrifuged, and serum was stored in glass tubes at -20 degree sign C until analysis. Three higher chlorinated PCB congeners (IUPAC nos. 138, 153 and 180), HCB, and the organic metabolite of DDT, p,p<<-DDE, were analysed with capillary gas chromatography with electron capture detection. Reliability was tested with gas chromatography-mass spectrometry. Results: There were no differences between the study groups of breast-fed and bottle-fed infants with regard to sex distribution, gestational age, birth-weight, age of the mothers, and smoking behaviour of the parents. In contrast, serum concentrations of all organochlorine compounds were significantly higher (P<0.0001) in breast-fed than in bottle-fed infants (mean): PCB 138, 0.38 vs. 0.10 {mu}g/l; PCB 153, 0.49 vs. 0.1 {mu}g/l; PCB 180, 0.31 vs. 0.04 {mu}g/l; {sigma}PCB, 1.19 vs. 0.29 {mu}g/l; HCB, 0.13 vs. 0.04 {mu}g/l; p,p<<-DDE, 1.05 vs. 0.18 {mu}g/l. Conclusions: Breast-feeding significantly increases the pollution of our infants with different organochlorine compounds as early as at 6 weeks of age. The progress of the present study will show whether this pollution will further increase with longer duration of breast-feeding, and whether breast-feeding bears any

  17. Mathematical Modeling of Liquid-fed Pulsed Plasma Thruster

    Directory of Open Access Journals (Sweden)

    Kaartikey Misra

    2018-01-01

    Full Text Available Liquid propellants are fast becoming attractive for pulsed plasma thrusters due to their high efficiency and low contamination issues. However, the complete plasma interaction and acceleration processes are still not very clear. Present paper develops a multi-layer numerical model for liquid propellant PPTs (pulsed plasma thrusters. The model is based on a quasi-steady flow assumption. The model proposes a possible acceleration mechanism for liquid-fed pulsed plasma thrusters and accurately predicts the propellant utilization capabilities and estimations for the fraction of propellant gas that is completely ionized and accelerated to high exit velocities. Validation of the numerical model and the assumptions on which the model is based on is achieved by comparing the experimental results and the simulation results for two different liquid-fed thrusters developed at the University of Tokyo. Simulation results shows that up-to 50 % of liquid propellant injected is completely ionized and accelerated to high exit velocities (>50 Km/s, whereas, neutral gas contribute to only 7 % of the total specific impulse and accelerated to low exit velocity (<4 Km/s. The model shows an accuracy up-to 92 % . Optimization methods are briefly discussed to ensure efficient propellant utilization and performance. The model acts as a tool to understand the background physics and to optimize the performance for liquid-fed PPTs.

  18. [Allergic colitis in exclusively breast-fed infants].

    Science.gov (United States)

    Sierra Salinas, C; Blasco Alonso, J; Olivares Sánchez, L; Barco Gálvez, A; del Río Mapelli, L

    2006-02-01

    Eosinophilic colitis is induced by antigens present in cow's milk proteins in formula or human milk. In the last few years, an increasing number of cases have been diagnosed in exclusively breast-fed infants. We performed a retrospective study of 13 infants diagnosed with allergic colitis in our unit between January 1997 and January 2004. All the infants had been exclusively breast-fed. In all patients, initial symptoms were digestive (12 with mucus and bloody stools). Onset of symptoms occurred at 0-3 months in 77 %. Laboratory data of the allergic compound were negative. The main locations were the descending and sigmoid colon (75 %). Biopsy demonstrated acute inflammation, with neutrophil infiltration and an increase in eosinophils. In all patients, initial treatment consisted of exclusion of cow's milk proteins from the mother's diet. Ten of the 13 patients showed no improvement, requiring exclusive administration of protein-free hydrolyzate. In 3 infants, breastfeeding was maintained (breastfeeding without cow's milk proteins plus hydrolyzate). Diagnosis of eosinophilic colitis is based on exclusion of other causes of specific colitis and typical endoscopic and ultrastructural findings. Moreover, a satisfactory response to dietary treatment must be demonstrated. This diagnosis should be considered in breast-fed infants with rectal bleeding without involvement of general health status.

  19. Active load current sharing in fuel cell and battery fed DC motor drive for electric vehicle application

    International Nuclear Information System (INIS)

    Pany, Premananda; Singh, R.K.; Tripathi, R.K.

    2016-01-01

    Highlights: • Load current sharing in FC and battery fed dc drive. • Active current sharing control using LabVIEW. • Detail hardware implementation. • Controller performance is verified through MATLAB simulation and experimental results. - Abstract: In order to reduce the stress on fuel cell based hybrid source fed electric drive system the controller design is made through active current sharing (ACS) technique. The effectiveness of the proposed ACS technique is tested on a dc drive system fed from fuel cell and battery energy sources which enables both load current sharing and source power management. High efficiency and reliability of the hybrid system can be achieved by proper energy conversion and management of power to meet the load demand in terms of required voltage and current. To overcome the slow dynamics feature of FC, a battery bank of adequate power capacity has to be incorporated as FC voltage drops heavily during fast load demand. The controller allows fuel cell to operate in normal load region and draw the excess power from battery. In order to demonstrate the performance of the drive using ACS control strategy different modes of operation of the hybrid source with the static and dynamic behavior of the control system is verified through simulation and experimental results. This control scheme is implemented digitally in LabVIEW with PCI 6251 DAQ I/O interface card. The efficacy of the controller performance is demonstrated in system changing condition supplemented by experimental validation.

  20. Frequency of polyploid cells in the bone marrow of rats fed irradiated wheat

    International Nuclear Information System (INIS)

    George, K.P.; Chaubey, R.C.; Sundaram, K.; Gopal-Ayengar, A.R.

    1976-01-01

    Diets containing different proportions of non-irradiated or irradiated wheat were fed to Wistar rats for 1 or 6 wk. Cytological analysis of the bone marrow showed no significant difference in the frequency of polyploid cells in the rats fed non-irradiated or irradiated wheat diets, even when the treated wheat was fed to the rats within 24 hr of irradiation. (author)