Ali Hasani

Nanoscience & Nanotechnology-Asia • 2020

By far the most important members of carbon-based materials family, are graphene, Carbon Nanotube (CNT) and Carbon Nanohorn (CNH). Thanks to their outstanding features and effective applications, have been broadly researched in recent times. Numerous ways have been proposed to synthesize graphene, CNT and CNH. This paper presents an overview of approaches to graphene, CNT and CNH synthesis, properties and applications. Most of the ways to create graphene is related to Hummer's method. Thanks to the exclusive electrical and thermal properties of graphene, it has been applied to build batteries, gas and vapor sensors, and elimination of numerous pollutants from water. Also, this review involves the conventional definition of the carbon nanotubes growth mechanism. Undoubtedly, an expert interpretation of nanotube growth at the atomic scale is one of the major challenges to improve nanotubes bulk synthesis procedure. In fact, a controlled growth may lead to get the ideal form of nanotube. Moreover, carbon nanohorn is a new member of single-graphene tubules family with a diameter of 3-6 nm and a length 35-45 nm. According to the latest reports, a new fluid including carbon nanohorns and ethylene glycol can be used for solar energy applications. Carbon nanohorns have an important role in increasing sunlight absorption as for the pure base fluid. Nanohorn spectral characteristics are far more interesting than those of amorphous carbon for the exclusive application. They can be used in important industries such as gas sensors, drug delivery, detecting some food borne contaminants.

Amir Navidfar, Taher Azdast, Ayub Karimzad Ghavidel

Journal of Applied Polymer Science • 2016

ABSTRACT In this work, multi‐walled carbon nanotubes (MWCNT) and poly(methyl methacrylate) (PMMA) pellets were compounded via corotating twin‐screw extruder. The produced MWCNT/PMMA nanocomposite pellets were injection molded. The effect of MWCNT concentration, injection melt temperature and holding pressure on mechanical properties of the nanocomposites were investigated. To examine the mechanical properties of the MWCNT/PMMA nanocomposites, tensile test, charpy impact test, and Rockwell hardness are considered as the outputs. Design of experiments (DoE) is done by full factorial method. The morphology of the nanocomposites was performed using scanning electron microscopy (SEM). The results revealed when MWCNT concentration are increased from 0 to 1.5 wt %, tensile strength and elongation at break were reduced about 30 and 40%, respectively, but a slight increase in hardness was observed. In addition, highest impact strength belongs to the nanocomposite with 1 wt % MWCNT. This study also shows that processing condition significantly influence on mechanical behavior of the injection molded nanocomposite. In maximum holding pressure (100 bar), the nanocomposites show highest tensile strength, elongation, impact strength and hardness. According to findings, melt temperature has a trifle effect on elongation, but it has a remarkable influence on tensile strength. In the case of impact strength, higher melt temperature is favorable. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016 , 133 , 43738.

Kyle Rego, Vincent Meunier

AIP Advances • 2019

The structural and mechanical properties of carbon nanotube knots are investigated using molecular dynamics simulations. Using parametric representations of mathematical (harmonic) knots, a method is provided for calculating the initial atomic coordinates of carbon nanotubes in the shape of arbitrary knots for use in molecular dynamics simulations. A computational stress-strain testing scheme is implemented and applied to (5, 5) knotted carbon nanotubes to determine their tensile strength, plastic limit, and relative knot strength. Stress-strain curves are given for (5, 5) carbon nanotube stopper knots. It is determined that a carbon nanotube’s tensile strength is reduced to at most 1/3 of its original strength when tied into a knot. It is also shown that it is possible to form tight and stable carbon nanotube knots by subjecting the knots to stress beyond the plastic limit. In contrast, loose knots stabilized by noncovalent interactions are not dynamically stable and spontaneously untie. To help understand the stability of loose carbon nanotube knots, the relationship between bending strain energy and curvature is studied using carbon tori. Our study demonstrates the possibility to tie carbon nanotubes into various stable knots and provides a general framework for the study of other macromolecular knots relevant to potentially useful nanotechnology.

Muhammad Mansoor, Shaheed Khan, Amjad Ali et al.

Journal of Composite Materials • 2019

Demand of special combination of different properties of the materials instigated the development of metal matrix composite. The carbon nanotubes being renowned for their excellent physical and mechanical properties are one of the major choices as strengthen material for metal matrix composites. To benefit their properties, the carbon nanotubes should be thoroughly dispersed and have wetting with the matrix. In the present study, a precursor of aluminum-carbon nanotubes was prepared by coating the nanotubes with titanium and used to fabricate the composite by induction melting. The precursor provided easy wetting, while induction melting facilitated dispersion of the nanotubes readily. Consequently, the composite exhibited noticeable augmentations in yield and tensile strength from 64 to 193 MPa and 81 to 227 MPa, respectively.

Jie Chen, Wen Wang, Sheng Zhang

AIP Advances • 2020

Carbon nanotube (CNT) films showing excellent mechanical and frictional performances are one of the most competitive candidates for fabricating functional surfaces; in particular, the bulk form of the forest-like vertical aligned CNT (VACNT) film and CNT sponge are idea candidates for making a flexible solid lubricant surface due to the fact that their porous network has a high potential to experience large deformation. In this article, the frictional behavior of the VACNT and CNT sponge against a millimeter scale copper sphere has been studied under various conditions within a home-built system. Due to the intrinsic mechanical instability of VACNTs, a higher friction state than the CNT sponge has been observed, and beyond that, VACNTs typically show a run-in process as a function of sliding circle caused by the formation and rearrangement of quasi-periodic cracks; on the contrary, the friction of the CNT sponge is very stable. In addition, we have pinpointed the effects of sliding velocity, relative humidity, and temperature on friction. The sliding friction was observed to be independent of the velocity and temperature; however, due to the increase in capillary force, friction increases with the increase in relative humidity.

Seisuke Ata, Chandramouli Subramaniam, Ayumi Nishizawa et al.

Advanced Engineering Materials • 2016

Thermal management of personal computer and other devices are critical issue for stable operation. Especially, soft and high thermal conductive materials are widely required for thermal transfer from heat source to heat sink. In this study, we prepared high thermal conductive composite with long single wall carbon nanotube, pitch‐derived carbon fiber and fluorinated rubber. Thermal conductivity of the composites is up to 80 W mK −1 which is higher than that of iron or brass. Furthermore, origin of the high thermal conductivity of the composites is investigated by using Weidman–Franz low. Carbon nanotubes enhance phonon thermal transfer between carbon fiber to carbon fiber.

Andrew John Ferguson, Jeffrey L. Blackburn

ECS Meeting Abstracts • 2019

While the unique chemical and physical structure of semiconducting single-walled carbon nanotubes (s-SWCNTs) were identified decades ago, marking these nanoscale materials as promising candidates for constituents in a variety of optical and electronic applications, the ability to generate high-purity samples has hampered efforts to validate these expectations. The intervening years have played witness to a number of elegant enrichment strategies aimed at extracting tailored semiconducting SWCNT species from the raw soot, from the use of subtly tunable surfactant interactions to the exploitation of specific DNA sequences. In contrast, we employ an enrichment approach based on conjugated polymers, typically derived from the fluorene moiety, since they show great promise with regards to their high selectivity and viability for scalable manufacturing approaches. As alluded to above, these fluorene-based (co-)polymers confer solubility on the s-SWCNT species, allowing for the preparation of highly enriched s-SWCNT dispersions that can be deposited using a variety of solution-processing approaches. Unfortunately, the strong van de Waals forces between the π-electron systems of the polymer and SWCNT that enable the selective extraction of semiconducting SWCNTs with high purity also make removal of the polymer difficult. Since these polymers typically have a wide bandgap they can act as an insulating coating on the surface of the individual SWCNTs within functional networks, inhibiting the transport of energy in the form of excitons and/or charge carriers. Here we demonstrate approaches that allow us to replace the strongly-bound polymers with derivatives that can be removed using simple solution-based chemical strategies, resulting in networks with modified energy transport properties. We show that removal of the polymer results in a significant enhancement of the charge carrier mobility and electrical conductivity in doped s-SWCNT networks. Finally, we extend the approach to samples strongly enriched in a single chiral s-SWCNT species, which allows us to employ transient spectroscopic techniques to probe exciton transport within the s-SWCNT network with high spectral fidelity. We show that the efficiency of exciton transport is subtly dependent on the complex interplay between polymer removal and carbon nanotube bundling. Our studies highlight a methodology by which high-performance s-SWCNT thin films can be prepared and discuss the implications of our findings on the potential to realize their promise for electronic and optoelectronic applications.

Unknown Author

East European Journal of Physics • 2019

Low power consumption, small device size and better controlled onto the charge carriers are the factors, that made Single-electron transistor (SET) a suitable candidate for molecular electronics; yet there are some improvements that can be done in order to use it practically. The single electron transistor (SET) operates through the tunnelling of electron via two tunnel junctions. Choosing a suitable island material plays a key role in the tunnelling of electron through the tunnel junctions. In the present work, the First principle calculations of carbon-nanotube and boron-nanotube based Single-Electron Transistors have been performed. The three types of configurations of nanotubes i.e. zigzag (5,0), armchair (3,3) and chiral (4,2), of the smallest possible diameter (approximately 4A ),have been used. The calculations have been carried out using Atomistic toolkit (ATK-VNL) simulation package which is a density functional theory (DFT) based package. In the present work, local density approximations (LDA) as well as generalized gradient approximation(GGA) have been used to demonstrate the properties of nanotubes-based SET. These approaches have been implemented for a nanotube that is lying just above the gate dielectric. On the either side of the dielectric the electrodes are present, source in the left and drain in the right. The metallic electrodes made of gold (W=5.28eV) and the dielectric material of the dielectric constant have been used. The charging energies and additional energies of both types of nanotubes-based SET in the isolated as well as in the electrostatic environment have been calculated using the approximations. The calculated values of the charging energies in the electrostatic environment have been found to be less than the charging energies in isolated configuration that shows the renormalization of molecular energy levels. Variations of total energies against gate voltages and Charge stability diagrams (CSD) have been discussed.

Marcelinus Christwardana, Linda Aliffia Yoshi

Reaktor • 2020

Experiments were conducted to study the correlation between current density and dissolved oxygen (DO) and to develop a model for estimating the value of current density in yeast MFC based DO biosensors. A curve between current density and DO was made, and data analysis was performed using free-online data fitting, namely zunzun.com. One linear regression and nine different exponential models are used as an approach to determine the correlation between current density and DO. The higher DO, the current density will increase rapidly. The most suitable model was chosen to describe the correlation between the current density and the DO. The coefficient of determination (R2), the sum of square absolute (SSQABS), and root mean square error (RMSE) are used to determine goodness or quality of fit. The exponential model shows a better fit to illustrate the correlation between current density and DO, with R2, SSQABS, and RMSE values were 0.9975, 0.4745 and 0.3444, respectively.

Mufid Ainun, Linda Suyati

Jurnal Kimia Sains dan Aplikasi • 2018

Study on bioelectrisity various carbon sources on the circuit series Microbial Fuel Cell using Lactobacillus plantarum has been conducted. This study aims to determine the electrical energy generated by various types of substrates in MFC and determe the effect of a series circuit of the electrical energy produced using Lactobacillus plantarum. The research stage consisted of preparation stages MFC components, electrical power measurements on variations in the type of substrate, and the measurement of electrical power in series circuit variation. Electrical power measurements were performed on a variety of substrate types by comparing the electrical power generated by the fructose, lactose and starch substrates while the electric power measurements with series variations are used in single series, series 2 and series 3. The results of the maximum electrical power measurement on the variation of fructose, lactose and starch substrate in MFC system using Lactobacillus plantarum were obtained respectively 10,26 mW; 63 mW and 27.47 mW. The maximum electric power generated in the MFC system uses Lactobacillus plantarum in a single circuit, series 2, series 3 series with lactose substrate obtained respectively of 63 mW, 164.74 mW and 290.51 mW. The measurement of electrical power showed that the lactose substrate produces a greater power than the other substrates. Series circuit capable of increasing electrical power in MFC system.

Zhuangzhuang Liu, Lei Zhou, Qi Chen et al.

Electroanalysis • 2016

Abstract The modifications of electrodes using graphene and graphene composites in microbial fuel cells (MFCs) and microbial electrolysis cells (MECs) have been widely applied for enhancing the electrochemical catalytic activity and performance of MFCs and MECs. Graphene as one of advanced materials has shown outstanding features for promoting practical applications of MFCs. This review summarizes the modification methods and characterization methods of graphene and related graphene composites on electrode surfaces in MFCs and MECs. The performance improvements of MFCs and MECs by various graphene related composites have been reviewed, which will provide an efficient guide for selecting suitable graphene material to modify electrodes in MFCs and MECs for improving their performance.

Muhammad Sohaib, Adeel Ahmed, Imran Aslam et al.

Current Graphene Science • 2019

Herein, the recent development and future perspectives of nanophotocatalysis has been discussed for the sustainable and green energy generation through microbial fuel cell (MFC). The artificial photosynthesis and biomass energy production methods have reviewed comprehensively. Further, the fabrication, fundamental aspects and purposes of MFC have been discussed to clearly elaborate the concept of energy production. A lot of effort have been done to convert light energy to biomass energy artificially which is then converted into electric or mechanical energy for further use. Recent age is facing plenty of challenges to convert the light energy to bioenergy.

Akihiro Kusuda, Xiu‐Hua Xu, Xin Wang et al.

ChemInform • 2011

Abstract Solkane® 365 mfc is proved to be an environmentally benign alternative solvent for the homocoupling reaction of terminal alkynes (I) under air to afford 1,3‐diynes (II) in high yields.

Tomasz Pajchrowski

COMPEL - The international journal for computation and mathematics in electrical and electronic engineering • 2011

Purpose The purpose of the paper is to find a speed control structure with two degrees of freedom robust against drive parameters variations. Application of structure model following control (MFC) and fuzzy technique in the controller of PI type creates proper non‐linear characteristics, which ensures controller robustness. Design/methodology/approach The use of proper structure with two degrees of freedom and non‐linear characteristic introduced by fuzzy technique ensures the robustness of the speed control system. The paper proposes a novel approach to MFC synthesis to be performed in two stages. The first stage consists in the set value of P type controller of model and the process controller simultaneously should be designing by fuzzy technique. At the second stage of the synthesis consist in tuning parameters of process fuzzy controller by the swarm of particles method (particle swarm optimization) on the basis of a defined quality index formulated in the paper. The synthesis is performed using simulation techniques and subsequently the behavior of a laboratory speed control system is validated in the experimental setup. The control algorithms of the system are performed by a microprocessor floating point DSP control system. Findings Use of proper structure with two degrees of freedom of the non‐linear fuzzy controller guarantees expected robustness and improves the dynamics of speed control significantly. Research limitations/implications The proposed structure of MFC was tested on a single machine under well‐defined conditions. Further investigations are required before any industrial applications. Practical implications The proposed controller synthesis and its results may be very helpful in robotic system where changing of system parameters is characteristic for many industrial robots and manipulators. Originality/value The paper proposes an original method of synthesis of robust system with two degrees of freedom system validated by simulation and experimental investigations.

Yong Li, Ying Lan Jia, Qi Han Zhang et al.

Advanced Materials Research • 2013

To overcome the shorting of inorganic gelatinous such as cement in plugging jobs, MFC-GM plugging agent is developed. MFC-GM is composed of 20% network building material, 70% gelatinous material, 9% activators, and 1% technologic behavior regulator and is used in aqueous slurries with water to cement ratio 1:1.4-1.8. The results of laboratory performance properties evaluation show that the depth of MFC-GM slurries squeezed into sandpack is far less, and the plugging strength of MFC-GM is, about 25MPa, far higher than G grade oilwell cement. This phenomenon is explained in terms of the functions of ingredients and the structure. MFC-GM can be used for plugging perforations and water producing zones, processing following characteristics: plugging radius is less than 0.8m and adjustable; initial setting time in rang 2-6 hours adjustably. MFC-GM plugging agent can meet the needs of unconsolidated sand gas reservoirs and improve plugging effect of gas well water-flooded layer and leakage zone.

Heng Yang Liu, Ling Lu

Advanced Materials Research • 2011

This article first introduce the importance of C++ language in the course of object-oriented, and the teaching mode before. Aim at the problems in the past mode of C++ teaching, the author analyses the problems in essence. And then, the author proposes a new method that is combination of MFC in C++ language teaching. Because of the MFC's inherent characteristics and the MFC are packaged by C++ language grammar. The instruction overcome many problems that exists in the last C++ language teaching, such as dull, lacks vividness and the lack of achievement. At the same time, the author has successfully applied for this instruction mode in his own teaching process.

Galina Rodionova, Solenne Roudot, Øyvind Eriksen et al.

BioResources • 2012

Microfibrillated cellulose (MFC), TEMPO-pretreated MFC, and hybrid polymer/MFC mix were used for the production of layered films with interesting properties for application in food packaging. The series of samples were prepared from MFC (base layers) using a dispersion-casting method. The same procedure as well as a bar coating technique was applied to form top layers of different basis weights. The barrier properties and formation of the layered films were investigated in relationship to the preparation procedures, combination of layers, and areal weight (basis weight). Characterization was done with respect to oxygen transmission rates (OTR), water vapor transmission rates (WVTR), tensile properties, and contact angles (CA) with water. The produced layered films yielded OTR values of 4 mL m-2 day-1 and fulfilled oxygen barrier requirements for a modified atmosphere packaging (MAP). Hornification of the MFC films, however, occurred during drying, which may result in a loss of the film’s beneficial properties.

Jun Cheol Jeon, Jung Woo Sohn, Seung Bok Choi

Advanced Materials Research • 2011

In this paper, identification of dynamic sensing characteristics of MFC(macro fiber composite) and PVDF(polyvinylidene fluoride) are carried out via experimental investigation. A clamped aluminum beam structure is prepared and experimental setup for beam vibration test is established with shaker system. MFC and PVDF are attached on the top and bottom surface of the beam structure, respectively and connected to data acquisition system. In order to verify the operating bandwidth, frequency responses of the smart beam structure are obtained from 0Hz to 5kHz under sine sweep excitation. For the identification of dynamic sensing characteristics, experiments for linearity and durability are conducted. It is observed that both MFC and PVDF have excellent sensing performance in measuring dynamic response and monitoring structural vibration.

Arpita Nandy, Vikash Kumar, Moumita Khamrai et al.

RSC Advances • 2014

Schematic representation of the series of events occurring in a MFC run with vermicompost soil.

He Rui Li, Kai Ting Wen

Advanced Materials Research • 2013

In this paper, MFC mappings is introduced and Ky Fan matching theorems for MFC mappings with transfer compactly open values are established in noncompact complete FC-metric spaces. As applications, a Fan-Browder type coincidence theorem and a minimax inequality are obtained. Our results unify, improve and generalize some known results in recent literature.

Mohamed Shaik Dawood, L. Iannucci, E. Greenhalgh et al.

Applied Mechanics and Materials • 2012

The potential use of MFC actuator as a tool for reducing low velocity impact induced delamination has been investigated using LS-DYNA explicit finite element code. An induced strain piezoelectric actuation model was implemented into LS-DYNA through its user defined material subroutine to simulate the piezoelectric effects while a cohesive based damage model was used to predict delamination. The numerical study confirmed that delamination could be reduced but the MFC required very high actuation voltages even in the case of very low energy impact which is not practically achievable with the existing actuator. Assuming powerful actuators are not something impossible in near future, this study provide useful information for advancing composite impact investigation using piezoelectric actuator as an integrated tool for improving its impact tolerance.

Zai Ping Chen, Ya Jing Yang

Advanced Materials Research • 2013

With the rapid development of computer network, automation and electronic commerce, more and more industrial production are in urgent need of the convenient and efficient integration of production and management system to adapt to the change and solve the condition of the onerous task, low efficiency, high cost, personnel tension. This article focuses on a typical industrial management system which is based on C/S architecture and uses MFC application framework. And it introduces ADO technology as the middle bridge which is used by the client to access databases. What is important is that the dynamic link library is used in the system to help ADO access database. The ADO technology has the characteristics of easily-using, high speed, low memory expenditure and less disk space, which optimize the system, make the system realize the high performance, high compatible data access.

Yue Zhang, Yan Feng Xu

Advanced Materials Research • 2012

Management Information System (MIS) is an Integration information systems engineering of computer technology and network communications technology. It can be more accurate, timely, comprehensive, detailed record of the data, while further processing of all kinds of information. In this paper, MFC, GPS and GE (Google Earth) technology is used in managing Old and Valuable Trees information, to solve a series of existing problems of labor management. At the same time of improving the efficiency of information management, it can achieve the implementation of monitoring and tree information Virtual Tour by combination in GPS the point marked and Google Earth software.

Yu Man Lin, Hao Rao

Applied Mechanics and Materials • 2013

Currently Gobang online game is not perfect, the most important problem is the man-machine play and online play can not be implemented together. In order to solve the problem, a Gobang online game was developed which could be not only a man-machine game, but also an online game. The message mechanism was designed to manage messages from network. And the overall system architecture and the main algorithms were described accordingly.

Jun An, Jin Song Fan

Applied Mechanics and Materials • 2014

Augmented Reality(AR) technology aims to integrate virtual objects with real scene by using computer technology and to realize real scenes enhancing. This paper presented a research method of using osgART to develop AR application programs in MFC (Microsoft Foundation Classes) environment, and discussed some related techniques. Corresponding procedures are given in each section, and a design example for product evaluation and exhibition is presented. This example was developed by the presented method in this paper, and its system ran in good condition after repeated tests. From the results of this paper, it can be seen that by using MFC and osgART to develop AR application programs, the seamless integration and interaction between the real environment and virtual objects can been easily realized, which will be benefit to improve the efficiency of developing AR application programs.

Y.‐J. He, Z.‐F. Ma

Fuel Cells • 2013

Abstract This investigation is performed to study the optimal operation decision of two‐chamber microbial fuel cell (MFC) system under uncertainty. To gain insight into the mechanism of uncertainty propagation, a Quasi‐Monte Carlo method‐based stochastic analysis is conducted not only to elucidate the effect of each uncertain parameter on the variability of power density output, but also to illustrate the interactive effects of the all uncertain parameters on the performance of MFC. Moreover, a systematic stochastic simulation‐based multi‐objective genetic algorithm framework is proposed to identify a set of Pareto‐optimal robust operation strategies, which is helpful to provide an imperative insight into the relationship between the mean and standard deviation of output power density. The results indicate that (1) the coefficient of variance (COV) value of output power density has a linear relationship with the COV value of each uncertainty parameter as well as all interactive parameters; and (2) a significant performance improvement with respect to both mean and standard deviation of power density is observed by implementing the multi‐objective robust optimization. These results thus validate that the proposed uncertainty analysis and robust optimization framework provide a promising tool for robust optimal design and operation of fuel cell systems under uncertainty.

Michael Holzinger, Alan Le Goff, Serge Cosnier

New J. Chem. • 2013

Supramolecular systems based on host-guest, electrostatic, or metal-ligand interaction and their use in bioelectrochemical applications are reviewed.

M. Rodríguez Arredondo, P. Kuntke, A. W. Jeremiasse et al.

Environmental Science: Water Research & Technology • 2014

Removal of nitrogen compounds from wastewater is essential to prevent pollution of receiving water bodies. Bioelectrochemical systems enable energy-efficient nitrogen removal and even recovery of ammonia from wastewaters.

Tao Yin, Xiao Min Cai, Lin Su et al.

Advanced Materials Research • 2013

Sediment microbial fuel cells (SMFCs) can generate electricity without maintenance in the field. SMFC is considered as an alternative renewable and sustainable power source. Though the SMFC is very appealing energy source, it presents certain challenges for real applications. Its output voltage and current are very low and its output voltage cant be increased by stacking several SMFCs in series in an open water body such as the lake. In this research, we construct and simulate a field SMFC with sediment from Xuanwu Lake in Nanjing, China. Open-circuit voltage of the SMFC is 750 mV and the maximal power density is 7.8 mW/m 2 . A custom-designed power management system (PMS) is developed to harvest energy from SMFC and boost the output power that can drive a wireless sensor. With the PMS, wireless sensor can utilize the harvested energy from SMFC and transmit data to computer without additional power source.

X. Xu, B.Z. Tian, J.L. Kong et al.

Advanced Materials • 2003

The immobilization of cytochrome c (Cyt‐c) in ordered mesoporous niobium oxide thin films is investigated for the first time. The direct electrochemical behavior of Cyt‐c assembled onto the inorganic matrix (see Figure) and the electrocatalytic properties of this assembly are studied. The results open a new doorway for the application of niobium oxides as bioanalytical devices.

Wenyan Tao, Dawei Pan, Qian Liu et al.

Electroanalysis • 2006

Abstract Acidic treated multiwalled carbon nanotubes (AMWNTs) were ground with water‐miscible room temperature ionic liquids, 1‐butyl‐3‐methylimidazolium tetrafluoroborate ([bmim]BF 4 ), and resulted in AMWNTs‐[bmim]BF 4 composite. Its electrical‐ionic conductivity and optical properties were compared with the other two types of carbon materials‐[bmim]BF 4 composites: pyrolytic graphite powder (PGP), pristine multiwalled carbon nanotubes (PMWNTs), through the ac impedance technology and Raman spectroscopy. The impedance data show that AMWNTs‐[bmim]BF 4 composite exhibits the highest conductivity. Raman spectra study exhibits that the [bmim]BF 4 can form gel with PMWNTs and AMWNTs but only form a viscous liquid with PGP. AMWNTs‐[bmim]BF 4 gel modified GC electrode was applied in direct electrochemistry of heme proteins (Hb and HRP) and it catalysis to the reduction of H 2 O 2 was investigated.

Huai‐Guo Xue, Zhi‐Quan Shen

Chinese Journal of Chemistry • 2002

Abstract A novel choline oxidase electrode was constructed by entrapping choline oxidase into polyaniline‐polyacrylonitrile composite film. The enzyme film was prepared by in situ electropolymerization of aniline into porous polyacrylonitrile‐coated platinum electrode in the presence of choline oxidase. The enzyme electrode exhibited sensitive and stable electrochemical response to choline. The kinetics analysis showed that the mass transport is partially rate‐limiting. The influences of pH, applied potential and temperature on the response of the enzyme electrode were also described.

Liping Huang, Shaoan Cheng, Guohua Chen

Journal of Chemical Technology & Biotechnology • 2010

Abstract Recalcitrant wastes including dyes, pesticides, explosives, heavy metals, polyalcohols, furan derivatives and phenolic substances, are of special concern owing to their recalcitrance and persistence in the environment. Bioelectrochemical systems (BESs) including microbial fuel cells (MFCs) and microbial electrolysis cells (MECs), integrate three important wastewater treatment options, namely, biological treatment, electrolytic dissociation and electrochemical oxidation/reduction, and are regarded as a new sustainable and effective strategy for treatment of these wastes. The simultaneous and cooperative roles of these multiple units running in parallel in BESs contribute to the efficiency of recalcitrant waste treatment, while substrate metabolism is considered to be a key step triggering different unit operations. An up‐to‐date review is provided on recent research and development in BESs‐based recalcitrant wastes treatment. MFCs and MECs, as two types of BESs, are summarized in terms of treatment efficiency, recalcitrant substance metabolic pathway and microorganism diversity after a brief introduction to the electrochemical process for recalcitrant waste treatment. The scientific and technical challenges that have yet to be faced in the future are also discussed. Copyright © 2010 Society of Chemical Industry

Guodong Liu, Charles Timchalk, Yuehe Lin

Electroanalysis • 2006

Abstract A fast, simple and sensitive bioelectrochemical magnetic immunosensing method is developed to monitor a potential insecticide biomarker, trichloropyridinol (TCP), in environmental sample. A magnet/glassy carbon (MGC) working electrode was used to accumulate immunocomplex associated magnetic beads and separate free and unbound reagents after liquid phase competitive immunoreaction among TCP antibody coated magnetic beads, TCP analyte and horseradish peroxidase (HRP) labeled TCP. The activity of HRP tracers was monitored by square‐wave voltammetry (SWV) by scanning electrocactive enzymatic product in the presence of 3,3′,5,5′‐tetramethylbenzidine dihydrochloride and hydrogen peroxide (TMB‐H 2 O 2 ) substrate solution. The electrochemical signal of enzymatic product was greatly enhanced by dual accumulation events: magnetic accumulation of enzyme tracers bound magnetic beads and constant potential accumulation of enzymatic product. The voltammetric characteristics of substrate and enzymatic product were investigated, and the parameters of SWV analysis and immunoassay were optimized. Under the optimal conditions the immunosensor was used to measure as low as 5 ng L −1 (ppt) TCP, which is 50‐fold lower than the value indicated by the manufacture of the TCP RaPID Assay kit (0.25 μg/L, colorimetric detection). The performance of the developed immunosensing system was successfully evaluated with river water samples spiked with TCP, indicating this convenient and sensitive technique offers great promise for decentralized environmental application. This technique could be readily used for detection of other environmental contaminants by developing specific antibodies against the contaminants and are expected to open new opportunities for environmental monitoring and public health.

Marco Frasconi, Gabriele Favero, Cristina Tortolini et al.

Electroanalysis • 2009

Abstract Heme peroxidase are ubiquitous enzymes catalyzing the oxidation of a broad range of substrates by hydrogen peroxide. In this paper the bioelectrochemical characterization of horseradish peroxidase (HRP) and soybean peroxidase (SBP), belonging to class III of the plant peroxidase superfamily, was studied. The homogeneous reactions between peroxidases and some common redox mediators in the presence of hydrogen peroxide have been carried out by cyclic voltammetry. The electrochemical characterization of the reactions involving enzyme, substrate and mediators concentrations allowed us to calculate the kinetic parameters for the substrate–enzyme reaction ( K MS ) and for the redox mediator–enzyme reaction ( K MM ). A full characterization of the direct electron transfer kinetic parameters between the electrode and enzyme active site was also performed by opportunely modeling data obtained from cyclic voltammetry and square wave voltammetry experiments. The experimental data obtained with immobilized peroxidases show enhanced direct electron transfer and excellent electrocatalytical performance for H 2 O 2 . Despite the structural similarities and common catalytic cycle, HRP and SBP exhibit differences in their substrate affinity and catalytic efficiency. Basing on our results, it can be concluded that peroxidase from soybean represents an interesting alternative to the classical and largely employed one obtained from horseradish as biorecognition element of electrochemical mediated biosensors.

Z. Feleke, Y. Sakakibara

Water Science and Technology • 2001

Biological denitrification and trace pesticide removal in a combined biofilm-electrode reactor/adsorption process has been investigated. In long-term (more than 260 days) continuous experiments, influent and effluent concentrations of nitrate, nitrite, isoprothiolane and gas composition were measured at different electric current and pesticide loading conditions. Experimental results showed that complete and stable denitrification was achieved in BER without accumulation of nitrite and nitrous oxide. Isoprothiolane (IPT) was removed by adsorption onto either granular activated carbon or silicone resin. Removal efficiency of IPT exceeding 97% was achieved and effluent concentration was below the guideline value (40 μg/l). Theoretically predicted effluent concentrations were in good agreement with the observed results. From these results, it is concluded that the combined process is applicable to treat nitrate and pesticide contaminated drinking water. Moreover, from comparison with former studies, different possible options to further enhance the decomposition of pesticide were suggested.

Sergey Kalyuzhnyi

Pure and Applied Chemistry • 2007

Abstract The well-known use of the microbiological process of anaerobic digestion (AD) to generate biogas (mixture of methane and CO 2 ) is now widely implemented for the production of renewable energy worldwide. In Russia, however, this is not the case despite huge amounts of organic wastes (OW) suitable for AD. This paper firstly inventories major flows of OW from various sectors of the national economy (agriculture, industry, households, etc.) and estimates their biogas potential. Special attention is paid to existing bottlenecks and barriers to implementation of biogas technology given the Russian socioeconomic conditions. The second part of the paper is devoted to a new emerging technology based on AD-microbial fuel cells (MFCs). The current status of research in this field in Russia is reviewed in comparison with worldwide developments. The possible niches for implementation of MFC technology in Russia (e.g., wastewater treatment) are pointed out, including its complements to conventional biogas processes.

Shelley T. Brown-Malker, Sue Read, Andrew Rowlands et al.

ECS Transactions • 2010

BioElectrochemical Systems are an emerging technology of interest. Central to the successful operation of these systems is the development of a biofilm on an electrode surface that facilitates the interaction of microorganisms capable of extra-cellular electron transfer. Porous graphite is typically chosen as the electrode material. However, other materials could contribute to a significant improvement in reactor performance. In order to evaluate these novel materials, a platform methodology is required. In this study, E-QCM-D was evaluated using a gold electrode, a mixed biofilm population and a challenging real influent (fermented solubilised sludge). The results gave real-time feedback on both the acoustic and electrochemical impedance of the working electrode, hence providing information about biofilm thickness, viscoelasticity, kinetics and mass transport. The use of E-QCM-D is novel for this field and has the potential to provide a wealth of new data to help optimise the performance of biofilms in these systems.

Uwe Schröder

Chemical Processes for a Sustainable Future • 2014

By generating electricity from microbially catalysed anodic oxidation processes, the greatest potential lies in the use of wastewater as a fuel, which allows wastewater treatment and energy recovery to be combined. A recent development has expanded the scope of bioelectrochemical systems from power generation and wastewater treatment to an increasing number of applications such as bioelectrochemically driven desalination and microbial electrosynthesis. This chapter provides an overview of microbial bioelectrochemical systems, their fundamentals and potential applications.

Bruce E. Logan

ChemSusChem • 2012

AbstractMicrobial 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.