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The electron transfer from cathode to azo dye Acid Blue 29 (AB29) using thionine (TH) and anthraquinone-2-sulfonate (AQS) redox mediators were investigated in dual chamber microbial fuel cells (DCMFCs). More than 90% of color was removed using electropolymerized TH (192 h) and AQS (264 h) cathodes. Chemical oxygen demand (COD) removal after anaerobic treatment in cathode chamber of TH-MFC, AQS-MFC and unmodified-MFC were 76.6 ± 1.7, 70.8 ± 2.5 and 18.3 ± 2.9%, respectively, which increased to 85.4 ± 1.5, 79.8 ± 3 and 20.6 ± 2.1%, respectively, after aerobic post treatment. Gas chromatography–mass spectrometry (GC–MS) investigations revealed the formation of aromatic amines in DCMFCs which were further degraded into low molecular-weight products in the aerobic post treatment. Electrochemical impedance spectroscopic (EIS) analysis showed lowest charge transfer resistance of TH-cathode which increased the electrochemical reactions and electron transfer rates. These results indicated that AB29 can be efficiently degraded by utilizing modified cathode based DCMFC-aerobic post treatment process along with bioelectricity generation.

This paper highlights and overview of and analysis of the patent laws in relation with the pharmaceuticals, the problems of public access to health in India. Moreover, patents have played a keen role in changing national and global innovation landscape. Patents are a kind of intellectual asset to whoever owns it, say, any individual or a company or it can be the government of a nation as well. IPR Laws are getting more and more popular these days. It provides a relief to the innovative creators that their invention, idea, discovery will remain theirs. And among them, patent law is the most important. However, when it comes to medicine, which is an essential item for every individual, the same patent laws act as a blockage to the access of these essential commodities. This article deals with the meaning of pharmaceutical drugs, and it’s patenting in India, along with problems that occurred because of it to the public access to health. However, IPR culture in India is anything but satisfactory. It demands interest, in depth knowledge and effective strategies for encouraging and building IPR activities and explore scientific and industrial research and innovation in India.

The plea bargaining process is quickly gaining popularity in the resolution of legal issues across the world. In common law and civil law nations, the applicability, scope, and operation of plea bargaining are clearly dissimilar. A comparative study of India, the United States of America, and Italy has been done in this research to critically analyse these disparities in regard to various jurisdictions. The extent to which plea bargaining is more favourable than harmful is debatable. This is because the practice of plea bargaining is said to call into question the basic premise of a trial, which is to find the truth and administer justice. The reality that an immediate justice administration system is required in India is unarguable. The researcher seeks to determine whether plea bargaining in India, in its current form and structure, is sufficient to achieve that goal by contrasting its benefits and drawbacks in the context of the Indian judicial system, and later, proposing reforms in the realm of this modern dispute resolution mechanism.

Increasing population in the world resulted in the crisis of both water and energy and therefore demanding the treatment of wastewater to make it fit for human use. The present study aims at the degradation of wastewater containing hazardous toluene along with the simultaneous recovery of energy, i.e., biogas which can overcome the crisis of both resources to some extent. For this, anaerobic digestion of toluene with varying concentration was achieved under the mesophilic condition when fed with different amount of substrate level. Examination of the feasible concentration of toluene and glucose (co-substrate) dosage to the reactor was performed in order to evaluate the performance of the anaerobic reactor. During the experiment, toluene degradation and chemical oxygen demand (COD) removal were examined periodically, and the efficiency of degradation was compared with the varying amount of glucose (0.5, 1, and 2 g/L). The high COD removal efficiency (77%) and methane (CH4) production (298 μL) was achieved after degrading 200 mg/L toluene sample when the reactor is fed with 1 g/L of glucose. Thus, 1 g/L was found to be the optimal amount of substrate level suitable for degradation and the efficiency is decreased if the amount of glucose is increased or decreased from this optimal amount. Furthermore, the scanning electron microscopy studies revealed the highly porous nature of sludge fed with 1 g/L glucose than others. Moreover, energy-dispersive x-ray analysis of sludges indicates the presence of different elemental components (carbon, oxygen, silicon, calcium) that confirmed the presence of microbial secretions involved in degradation.

2,4,6-Trichlorophenol (TCP) was bioelectrochemically treated in anodic and cathodic compartments of two identical dual chambered microbial fuel cells MFC-A and MFC-B under anaerobic and aerobic conditions, respectively, and energy was recovered in the form of electricity. It was observed that MFC-B with bio-cathodic treatment of TCP outcompeted the MFC-A with bio-anodic treatment. The maximum power density for MFC-A with bio-anode was found to be 446.76 mW/m2 while for MFC-B with bio-cathode it was 1059.58 mW/m2. The MFC-B consistently showed higher coulombic efficiency, power density and chemical oxygen demand removal efficiency indicating the better performance of the MFC-B as compared to the MFC-A. Scanning electron micrograph also confirmed better accumulation of microbes on the anode of MFC-B and hence its better performance in terms of energy recovery. Some major genera present in the microbial community were quantified using quantitative real-time polymerase chain reaction technique. It also confirmed the dominance of electroactive species in the bio-anodic sludge of MFC-B over the bio-anodic sludge of MFC-A. Cyclic voltammogram also asserted better electrochemical activity of the bio-cathode in the treatment of chlorinated phenol toxicants in MFC-B system. The study shows that MFC can be a viable option in treatment of recalcitrant chemical compounds like TCP with the generation of energy in the form of electrical power.

In this study, an azo dye (Acid Blue 29 or AB29) was efficiently degraded with acetate as co-substrate into less contaminated biodegraded products using an integrated single chamber microbial fuel cell (SMFC)-aerobic bioreactor set-up. The decolorization efficiencies were varied from 91 ± 2% to 94 ± 1.9% and more than 85% of chemical oxygen demand (COD) removal was achieved for all dye concentrations after different operating time. The highest coulombic efficiency (CE) and cell potential were 3.18 ± 0.45% and 287.2 mV, respectively, for SMFC treating 100 mg L−1 of AB29. Electrochemical impedance spectroscopy (EIS) revealed that the anode resistance was 0.3 Ω representing an entirely grown biofilm on the anode surface resulted in higher electron transfer rate. Gas chromatography coupled mass spectrometry (GC–MS) investigation demonstrated that initially biodegradation of AB29 started with the cleavage of the azo bond (-N=N-), resulted the biotransformation into aromatic amines. In successive aerobic treatment stage, these amines were biodegraded into lower molecular weight compounds. The 16S rRNA microbial community analysis indicated that at phylum level, both inoculum and dye acclimated cultures were mainly consisting of Proteobacteria which was 27.9, 53.6 and 68.9% in inoculum, suspension and anodic biofilm, respectively. At genus level, both suspension and biofilm contained decolorization as well as electrochemically active bacteria. The outcomes exhibited that the AB29 decolorization would contest with electrogenic bacteria for electrons.

Magnesium Ferrite (MgFe2O4) spinel structures prepared by a solid-state reaction was used as an anode modifier in the microbial fuel cell (MFC) treatment of Congo red dye. The performance of the reactors with unmodified stainless-steel mesh anode (CR-1) and MgFe2O4 coated stainless steel mesh anode (CR-2) were tested and compared followed by aerobic treatment. The peak power density was observed to be 295.936 (CR-1) and 430.336 mW/m2 (CR-2) revealing increased bioenergy output and better electron transfer in the reactor with the MgFe2O4 modified anode. The final decolourisation efficiencies were found to be 92.053% for CR-1 and 98.386% for CR-2. The formation of metabolites (diaminonaphthalene-1-sulfonate, 1-(biphenyl-4-yl)-2-(naphthalene-2-yl) diazene, benzidine and phthalic acid, monoethyl ether) during the anaerobic-aerobic biotreatment of azo dye was confirmed using Gas chromatography coupled Mass spectrometry system. Scanning electron microscopy confirmed a uniform coating of MgFe2O4 on the anode surface with evidence of biofilm formation in the system. Electrochemical studies confirmed the superior performance of spinel coated anode with enhanced redox activity. In addition, the charge-discharge studies confirmed the high capacitive nature of the modified electrode improving the electrodes charge holding capacity. The study suggested an effective treatment strategy for the treatment of Congo red dye.

The Lie symmetries, conservation laws, and exact solutions of a generalized nonlinear system and a (2+1)-dimensional generalized Nizhink-Novikov-Veselov (NNV) equation, arising in the study of hydrodynamics, are investigated. The multiplier approach is employed to compute the conservation laws for systems under consideration. The Lie point symmetries are derived and the association between symmetries and conserved vectors are established using symmetries conservation laws relationship. The double reduction theory is utilized which results in the reduction and exact solutions of models under investigation. All cases are discussed in detail and new solutions are determined.

The present investigation emphasizes on the anaerobic biological treatment of benzene containing wastewater under mesophilic temperature towards elimination of chemical oxygen demand (COD) and simultaneous recovery of methane-enriched biogas. The anaerobic degradation of benzene has been examined over the influence of different co-substrates in an anaerobic bioreactor of 100 mL volume. Acetate and glucose are added as co-substrates with a concentration of 1 gL−1 to monitor and compare the methanogenesis during anaerobic digestion. During the experiment, COD removal efficiency of 85% was achieved. Methane (CH4) and carbon dioxide (CO2) production has been observed to be higher in glucose (1 gL−1) fed anaerobic reactor with the highest amount of CH4 (306 μL) and CO2 (248 μL) produced under mesophilic condition (35 ± 1 °C), pH of 6.82, conductivity of 0.073 μS cm−1 and at a concentration of 200 mgL−1 of benzene analysed using gas chromatography coupled with thermal conductivity detector (TCD). Scanning electron microscopy (SEM) analysis demonstrated the high porous structure of anaerobic sludge with uniform channels confirming better mass transfer and high benzene removal. Energy dispersive x-ray (EDX) showed various constituent elements present in the microbial sludge including carbon, oxygen, magnesium, silicon, aluminium, and zinc. The specific methanogenic activity was found to be 1.8 mM CH4 gVS−1 day−1 using acetate as a source of energy. The study reveals that the anaerobic reactor has made possible biogas production and COD removal through efficient degradation of complex substrate like benzene in wastewater.

Highly conductive reduced graphene oxide/ tungsten oxide (rGO/WO3) nanofibrous-modified carbon cloth (CC) based cathode was fabricated for electroreduction of carbon dioxide (CO2) through microbial electrosynthesis (MES). The modified rGO/WO3 nanofibrous functionalized cathode showed improved performance in terms of volumetric acetate production, which was 41% higher than the unmodified electrode. The alteration of the cathode also helped to reduce the resistance to flow the electron and increased the MES coulombic efficiencies. Adhesion of bacterial community on the electrode surface was confirmed by scanning electron microscopy (SEM). The electrochemical analysis results suggested the role of nanocomposite in improving the electrical charge holding capacity by enhancing capacitance. Based on higher biocompatibility, permeability, and electrode conductivity, the modified cathode allows a more attractive approach for bioprocess applications.

Microbial electrosynthesis (MES) is a promising technology for carbon dioxide (CO2) sequestration to produce biofuel; however, its practical application is still a challenging due to lower biofuel production rates. This limitation can be alleviated by regulating the interfacial properties of biocathode. The present study investigates the feasibility of novel conducting polymer-based redox mediator modified electrodes to enhance the production of value-added chemicals. The redox mediators investigated in the study are neutral red (NR) and methyl viologen (MV), while polyaniline (PANI) was chosen as supporting conducting polymer. The electrochemical properties of MV-PANI and NR-PANI electrodes were investigated using cyclic voltammetry and electrochemical impedance spectroscopy. The results displayed an increase in biofuel production rates for modified electrodes with MV-PANI and NR-PANI electrodes showing respectively 1.3- and 1.1-times higher production of acetate respectively, as compared to plain Toray carbon paper electrodes. Furthermore, the coulombic efficiencies of acetic acid followed the trend: MV-PANI (74.15 ± 5%) > NR-PANI (64.20 ± 5%) > TCP (52.40 ± 5%). The improved performance of modified electrodes compared to plain carbon paper electrode could be attributed to increased extracellular electron transfer, reduced internal resistance of the system and enriched biofilm formation on the modified cathode.

Numerous traditional methods are available for the conversion of waste to energy (WTE) such as incineration, anaerobic digestion, pyrolysis, gasification. Most of them suffer from low efficiency and high energy requirements. Microbial fuel cell (MFC) technology is an excellent alternative for the generation of renewable and sustainable energy and has the potential to help alleviate the current global energy crisis. The total wastewater generated in India is almost 250% of the total treatment capacity, and the Government is, therefore, looking for a sustainable solution for the treatment of waste. Indian population consumes around 700 billion cubic meters of water annually, and this figure will rise to 950 and 1422 billion m 3 by 2025 and 2050 respectively. Although treatment of wastewater is a serious concern, the energy recovery potential of wastewater has not yet been fully developed. A survey has been conducted through this study, and it was estimated that MFC technology has the potential to generate around 23.3 and 40 Tera Watt (TW) power by 2025 and 2050 by treating wastewater generated throughout India (urban areas) if utilized properly. This review article presents a various aspect of MFC technology for a proper understanding by the readers. This will be a unique study wherein the energy recovery potential of the wastewater produced in the Indian subcontinent has been estimated through MFC technology. A number of factors affecting the performance of MFC such as electron losses, reactor configuration, and varying concentration must be taken into account to augment output energy. The article summarizes an extensive literature survey of some selected papers published in the last decade.

Recently, treatment of waste water using biofuel technology has gained more attention because of its bio-sustainable resource by generating powering microbes (electrical energy) which exponentially reducing dependence of fossil fuels. In the last one decade, one of the bioelectro-chemical approach; microbial electrolysis cell (MEC) has been developed to treat waste water and energy production. It is considered as a potential green technology to tackle the issues of energy shortage and global warming. This technique employs conversion of waste water (which contain organic matter) into hydrogen or a variety of value-added products (acetate, hydrogen peroxide, methane, ethanol) via electrochemically active bacteria (electrogenes). Significant outcomes of MECs offers a new solution to emerging environmental issues related to waste water treatment, energy and resource recovery as well. In future, it is expected that treatment of industrial waste water using MECs has become a promising renewable green technology to manage waste water and biofuels production. The present chapter mainly reviews utilization of various polymer-based electrode materials in MECs for treatment of waste water along with their future potential substrates.

Anaerobic digestion (AD) is a sustainable wastewater treatment technology which facilitates energy, nutrient, and water recovery from organic wastes. The agricultural and industrial wastes are suitable substrates for the AD, as they contain a high level of biodegradable compounds. The aim of this study was to examine the AD of three different concentrations of phenol (100, 200, and 300 mg/L) containing wastewater with and without co-substrate (acetate) at four different temperatures (25, 35, 45, and 55 °C) to produce methane (CH4)-enriched biogas. It was observed that the chemical oxygen demand (COD) and phenol removal efficiencies of up to 76% and 72%, respectively, were achieved. The CH4 generation was found higher in anaerobic batch reactors (ABRs) using acetate as co-substrate, with the highest yield of 189.1 μL CH4 from 500 μL sample injected, obtained using 200 mg/L of phenol at 35 °C. The results revealed that the performance of ABR in terms of degradation efficiency, COD removal, and biogas generation was highest at 35 °C followed by 55, 45, and 25 °C indicating 35 °C to be the optimum temperature for AD of phenolic wastewater with maximum energy recovery. Scanning electron microscopy (SEM) revealed that the morphology of the anaerobic sludge depends greatly on the temperature at which the system is maintained which in turn affects the performance and degradation of toxic contaminants like phenol. It was observed that the anaerobic sludge maintained at 35 °C showed uniform channels leading to higher permeability through enhanced mass transfer to achieve higher degradation rates. However, the denser sludge as in the case of 55 °C showed lesser permeability leading to limited transfer and thus reduced treatment. Quantitative real-time PCR (qPCR) analysis revealed a more noteworthy change in the population of the microbial communities due to temperature than the presence of phenol with the methanogens being the dominating species at 35 °C. The findings suggest that the planned operation of the ABR could be a promising choice for CH4-enriched biogas and COD removal from phenolic wastewater.

A combined anaerobic–aerobic process involving a single chambered microbial fuel cell (SMFC) followed by an aerobic downstream treatment process is selected for the complete removal of reactive orange 16 (RO 16) from contaminated water. The degradation of azo-dye in SMFC results in the formation of aromatic amines with simultaneous production of electricity. The degradation products of the SMFC were further treated in an activated sludge downstream process in order to provide complete solution from dye wastewater. More than 90% of the chemical oxygen demand (COD) was removed in the combined process for all the test concentrations. The maximum output cell potential and the coulombic efficiency (CE) were 423 mV and 3.4% respectively. SEM images of the mixed microbial culture showed the presence of cocci, diatoms and rod shaped bacteria. Cyclic voltammetry revealed that a perfect redox process took place in the SMFC system. The results of the gas chromatography coupled with the mass spectroscopy (GC/MS) technique showed that RO 16 was first converted into aromatic amines in SMFC which were further transformed into phthalic acid and finally into benzoic acid. The results of the present work demonstrate that wastewater containing complex and toxic dyes can be successfully treated in SMFC followed by aerobic post-treatment along with energy recovery.

Microbial fuel cells (MFCs) have gained a recent attention as a mode of converting organic waste into electricity using variety of biodegradable substrate as fuel. Different designs of MFCs are available for different purposes, however dual and single chamber MFCs are common used for energy generation. Type of electrode materials, membrane, pH, electron transfer rate, reactor design and operating conditions affects the performance of MFC. Microbes actively catabolize substrate and transform their chemical energy into electrical energy. MFCs could be utilized as power generator in small devices such as biosensor, pacemakers and by doing small modification (Microbial Electrolysis Cell) can produce hydrogen a potential fuel in cathodic chamber. Besides the merits of this technology, it is still immature and faces practical limitations such as low power and current density. The construction and analysis of MFCs requires knowledge of different disciplines ranging from microbiology and electrochemistry to materials and environmental engineering. This article presents various aspects of MFC technology for proper understanding of the readers. This article present an extensive literature survey of some selected papers published on MFC technology in the last decade. Various practical solutions have been suggested to overcome the practical challenges of this technology.

In this article, we study time–space fractional advection–dispersion (FADE) equation and time–space fractional Whitham–Broer–Kaup (FWBK) equation that have significant roles in hydrology. We introduce suitable transformations to convert fractional-order derivatives to integer-order derivatives and as a result these equations transform into partial differential equations (PDEs). Then the Lie symmetries and the corresponding optimal systems of the resulting PDEs are derived. The symmetry reductions and exact independent solutions based on optimal system are investigated which constitute the exact solutions of original fractional differential equations.

Fabrication of superior and cost-effective cathodic materials is vital in manufacturing sustainable microbial electrolysis cells (MECs) for biofuels production. In the present study, a novel manganese dioxide (MnO2) coated felt cathode (Mn/CF) has been developed for MECs using electrodeposition method via potentiostat. MnO2 is considered to encourage exogenous electron exchange and, in this way, improves the reduction of carbon dioxide (CO2). MnO2, as a cathodic catalyst, enhances the rate of biofuel production, electron transfer, and significantly reduces the cost of MECs. A maximum stabilized current density of 3.70 ± 0.5 mA/m2 was obtained in case of MnO2-coated Mn/CF based MEC, which was more than double the non-coated carbon felt (CF) cathode (1.70 ± 0.5 mA/m2). The dual chamber Mn/CF-MEC achieved the highest production rate of acetic acid (37.9 mmol/L) that was significantly higher (43.0%) in comparison to the non-coated CF-MEC. The cyclic voltammograms further verified the substantial enhancement in the electron transfer between the MnO2 coated cathode and microbes. The obtained results demonstrate that MnO2 interacted electrochemically with microbial cells and enhanced the extracellular electron transfer, therefore validating its potential role in biofuel production. The MnO2 coated CF further offered higher electrode surface area and better electron transfer efficiency, suggesting its applicability in the large-scale MECs.

This study aims to examine the effect of different co-substrates on the anaerobic degradation of pentachlorophenol (PCP) with simultaneous production of biogas. Acetate and glucose were added as co-substrates to monitor and compare the methanogenic reaction during PCP degradation. During the experiment, a chemical oxygen demand (COD) removal efficiency of 80% was achieved. Methane (CH4) production was higher in glucose-fed anaerobic reactors with the highest amount of CH4 (303.3µL) produced at 200ppm of PCP. Scanning electron microscopy (SEM) demonstrates the high porous structure of anaerobic sludge with uniform channels confirming better mass transfer and high PCP removal. Quantitative real-time PCR (qPCR) revealed that methanogens were the dominating species while some sulfate reducing bacteria (SRBs) were also found in the reactors. The study shows that strategic operation of the anaerobic reactor can be a feasible option for efficient degradation of complex substrates like PCP along with the production of biogas.

Simultaneous bioelectricity generation and dye degradation was achieved in the present study by using a combined anaerobic-aerobic process. The anaerobic system was a typical single chambered microbial fuel cell (SMFC) which utilizes acid navy blue r (ANB) dye along with glucose as growth substrate to generate electricity. Four different concentrations of ANB (50, 100, 200 and 400 ppm) were tested in the SMFC and the degradation products were further treated in an activated sludge post treatment process. The dye decolorization followed pseudo first order kinetics while the negative values of the thermodynamic parameter ∆G (change in Gibbs free energy) shows that the reaction proceeds with a net decrease in the free energy of the system. The coulombic efficiency (CE) and power density (PD) attained peak values at 10.36% and 2,236 mW/m2 respectively for 200 ppm of ANB. A further increase in ANB concentrations results in lowering of cell potential (and PD) values owing to microbial inhibition at higher concentrations of toxic substrates. Cyclic voltammetry studies revealed a perfect redox reaction was taking place in the SMFC. The pH, temperature and conductivity remain 7.5–8.0, 27(±2°C and 10.6–18.2 mS/cm throughout the operation. The biodegradation pathway was studied by the gas chromatography coupled with mass spectroscopy technique, suggested the preferential cleavage of the azo bond as the initial step resulting in to aromatic amines. Thus, a combined anaerobic-aerobic process using SMFC coupled with activated sludge process can be a viable option for effective degradation of complex dye substrates along with energy (bioelectricity) recovery.