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The evolution of the dark energy within the scope of a spatially homogeneous and isotropic Friedmann–Robertson–Walker model filled with barotropic fluid and dark energy is examined. We have considered the two cases of an interacting and non-interacting two-fluid (barotropic and dark energy) scenario and obtained the exact solutions to the corresponding field equations. In an interacting model, we have considered linear as well as quadratic interaction between dark sectors of the universe. We have also given the quadrature form for general interaction coupling parameter via Q = αρ m n, n ⩾ 1 and discussed the evolution of energy densities and effective equation of state with cosmic time for flat, closed, and open universes. It is also examined that the matter energy density is dominated in early phase of the universe, whereas the dark energy density is dominated in later phase of the universe for both scenarios, which is in concurrence with current observations.

This article puts forward to provide the state of pollution of the Ganga River in India along with its tributaryriver Gomti. A lot of research works for monitoring and assessment ofGanga river water have been doneby many investigators in the past. With its pietism, Ganga River water is considered a great prominentriver in India so that people use the water to perform last rites to their loved ones. It is deteriorated due todischarge of untreated wastes, chemicals, heavy metals and sewage from Industries and Cities. This paperreveals governmental efforts toward river water preservation, not executed properly because of the apatheticapproach of people in our country. In India lack of sanitation in rural areas is also a major contributor ofriver water pollution. In the urban mega cities which are fast-growing- hotspots, pollution levels worsenalong the Ganga River including its tributary rivers. Some studies by CPCB reveal high BOD levels atdownstream, biochemical oxygen demand (BOD) levels were high towards downstream at Haridwar,Kannauj, Kanpur and on peak at Varanasi but alarming is that, almost at all the stretches of Ganga riverand its tributaries, level of pollution is getting escalated. Alone Uttar Pradesh contributes 90% of Gangapollution so that it is chosen for further research including Gomti River a significant tributary of Ganga.Although there are many contributions of researchers in cleaning Ganga but structured and stringentmeasures for the environment are to be taken.

A pot experiment was carried out to evaluate the impact of plant growth regulators (PGRs) on translocation and accumulation of zinc (Zn) in grains of four wheat varieties of varying Zn sensitivities. Different concentrations of two (gibberellic acid and cytokinin) PGRs viz., control, 10 ppm gibberellic acid (GA), 20 ppm gibberellic acid (GA), 10 ppm cytokinin (kinetin), 20 ppm cytokinin (kinetin), 10 ppm gibberellic acid (GA) + cytokinin (kinetin), 20 ppm gibberellic acid (GA) + cytokinin (kinetin) were applied under different Zn regimes (control), soil application of 5 mg Zn kg-1 soil and soil application of 5 mg Zn kg-1 soil + foliar applications of 0.5% ZnSO4.7H2O + 0.25% lime). Four contrasting wheat varieties i.e., UP262 & PBW175 (Zn inefficient), UP2628 & UP2554 (Zn efficient); were tested for enzyme activities, yield attributes and Zn content in various plant parts. Regarding influence of PGR levels, the maximum CA and SOD activities were recorded under 20 ppm GA and control respectively. The grain yield, straw yield and grain Zn content was found to be the maximum under 10 ppm GA+cytokinin, 20 ppm GA and 20 ppm cytokinin respectively. Among all the methods used, soil along with foliar spray (Zn S+F) was found to be the most effective in improving all the crop parameters. Among varieties, the efficient sets of varieties (UP2628 & UP2554) performed better than Zn inefficient varieties. The use of plant growth regulators along with efficient delivery method could enhance the transport and accumulation of Zn in grains of wheat.

The Casson fluid model, which is very significant in the biomechanics and polymer processing industries, is another term used to describe non-Newtonian fluid behavior. This study of Casson fluid model on unsteady MHD Casson fluid flow with Soret-Dufour effect past a vertical plate embedded in porous medium in the presence of radiation with heat generation/absorption and viscous dissipation is presented in this research article as a numerical investigation of non Newtonian Casson fluid with applied effects. Regulating partial differential equations have been used to explain the mathematical model of the flow field. The Crank-Nicolson implicit finite difference approach has been used to numerically solve non-dimensionalized flow field governing equations. Concentration, temperature, and velocity profile effects of non-dimensional factors have been investigated using tables and graphs as aids. Tables have also been used to observe fluctuations in factors like skin friction, the Nusselt number, and the Sherwood number in relation to other parameters.

The aim of this paper is to introduce matrix polynomials L(M,?,?) n (x) and establish some properties viz, hypergeometric representation, generating matrix relations, integral representations, recurrence relations, summation formulas, series relation, fractional integral and derivative operators.

Development and demonstration of soluble lead redox flow battery (SLRFB) is hindered due to its limited cycle life caused by the formation of lead dendrites, oxygen evolution reaction (OER), and accumulation of PbO2 sludge. OER leads to an imbalanced deposition of Pb metal at anode and PbO2 at cathode. As a result, complete oxidation of Pb is stalled during discharge of SLRFB. Besides, sluggish kinetics of cathode reaction results in accumulation of PbO2. Due to incomplete dissolution and accumulation of both active materials, concentration of Pb2+ decreases continuously in the electrolyte. Under such conditions, repeated charge–discharge cycling leads to the failure of SLRFB. In this study, we propose and demonstrate a novel route of using an auxiliary gas-diffusion electrode to obviate these problems to help in extending the cycle life of SLRFB. The auxiliary electrode is operated either as an air electrode or a hydrogen electrode. When the auxiliary electrode is an air electrode, it is used as positive electrode, and on coupling with anode of SLRFB, it forms a galvanic Pb–air flow cell that on discharge helps in oxidizing Pb metal to Pb2+ ions. When the auxiliary electrode is a hydrogen electrode, it is used as negative electrode, and on coupling with cathode of SLRFB, it forms a galvanic H2–PbO2 flow cell which on discharge reduces PbO2 to Pb2+ ions and mitigates the adverse effect of sludge accumulation in SLRFB.

Solar adsorption refrigeration systems are indispensable in the areas of cooling such as air conditioning, ice making, food preservation, medicine and vaccine storage etc in remote areas. It is cheaper than other devices and lack in noise and corrosion. It is completely an eco-friendly system which could be driven by low grade waste heat. Consumption of electricity is very less in this system as compared to other fields due to the elimination of compression process in adsorption refrigeration. Most of the adsorption system delivers a COP between 0.1 and 0.2 and exceptions are also there. Because of the technical, economic and environmental problems, researches are going on in these areas. Nowadays it is incorporated with vapour compression system to make hybrid system in order to achieve a greater COP and efficiency. This paper presents the basic and advanced aspects of adsorption refrigeration cycle and its hybrid arrangements with pre-existing system. This paper described the different types of conventional and novel adsorbent – adsorbate working pairs and provides detailed review about the past and present state of art research in this field.

The present study proposed the water generating system through humidification-dehumidification desalination unit and RO powered by organic Rankine cycle to generate both power and drinking water from the waste heat of Naval Ship by using a low-temperature organic Rankine cycle. Waste heat from the naval ship is used in order to run the topping cycle namely the organic Rankine cycle for power generation which operates the RO system for drinking water. A water-heated humidification dehumidification (HDH) desalination unit is also integrated with the organic Rankine cycle system to produce additional freshwater. The mass and energy balance equations are designed to analyze the thermodynamic performance of the cogeneration of the power-water system at the designed conditions. Suitable working fluids for the organic Rankine cycle are chosen on the basis of thermophysical properties i.e. lower boiling point, critical temperature & pressure and global warming potential. Furthermore, the impact of various vital parameters like extraction pressure, vapor extraction ratio, condenser temperature, turbine inlet pressure, etc. on the performance. It was founded that the impact of extraction parameters on the cycle, the net power, total efficiency and water production is 16.74 kW, 42.10% and 75.18 kg h−1 respectively. The extraction ratio variation causes the improvement in the water production and power generation and lower extraction ratio has better results. The RO System used is direct mechanical coupling which uses the power to run the system and produces the water, 2.4L of drinking water is produced using 16.74 kW power, respectively.

The present era is living with very fast growing pace despite having the usual kind of natural resources available that are always we have in a limited amount with expansible and irreversible in nature. It has to be bothered about saving and sustaining our natural resources for better future along with the development of self sustainable, economic and environment friendly technology such as solar decontamination systems. And, current situation with water stress or even costlier potable water availability motivates us to work with such systems that have easy technology, self sustainable, and eco friendly establishment serving the society. This work shows a comparative performance analysis between single and double solar stills with four combinations as with circular and square fin, jute and black cotton wick for energy matrix and enviroeconomic considerations. Still with square fins found better and having less embodied energy (379.62 kWh) comparative to others. It has yield up to 4.55 l/m2/day with 36.6 tons CO2 lessening for thirty years of the overall systems performing life. Equivalent minatory value for the CO2 lessening scored by the proposed system is noticed as $365.63. Further, still have least time recovery for the equivalent energy payout and superior adaptation efficiency of the system through its working of life cycle i.e. 0.48 years, and 0.44 correspondingly.

The present work explains the engine performance using waste cooking oil (WCO) blended with diesel. The viscosity of WCO can be reduced to be comparable with diesel by preheating at 90°C and thus improves the engine combustion efficiency. For the purpose of preheating, a shell and tube heat exchanger were designed. The optimized tube and shell diameters of the heat exchanger were estimated as 17 and 460 mm, respectively. Pressure drops in tube and shell sides changed from 28.40 - 27.40 Pa and 0.025 - 0.1 Pa respectively. Flue gas energy contents varied from 4000 W to 16000 W at the mass flow rate of 0.03-0.08 kg/s. Useful energy gained by the heat exchanger for waste cooking oil preheating varied from 1200-5500 W at 1200-3000 rpm. Kinematic viscosity for WCO was 51.85 cSt and it changed to 7.55 - 17.5 cSt for blends of 10 - 30% with diesel at 40°C. As the blending % of WCO with diesel increased, there was a minor drop in brake power because of lower calorific value of the mixture. There was a minor increment of torque because of preheating. Preheated fuel blends injection into the cylinder facilitated better fuel efficiency. Minimum and maximum values of exhaust gas temperature were 345°C and 385°C at 1200 and 3000 rpm of engine speeds respectively.

The objective of this paper is to introduce the effect of Soret-Dufour, a higher-order chemical reaction on MHD Casson fluid with a heat source/sink over a vertical plate embedded in a porous medium. The observation reveals different parts of the flow of Casson fluid, heat, and mass transfer. Crank-Nicolson finite difference method utilized for solving Non-dimensional governing partial differential equations. Computations are executed graphically to analyze the change of velocity, temperature, and concentration as well as Skin-friction, Nusselt number, and Sherwood number for different values of parameters Dufour number Du = 0.2, Chemical reaction parameter Kr = 1.2, heat source/sink parameter Q = 2, Schmidt number Sc = 0.6, Soret number Sr = 1.5, order of chemical reaction n = 2, radiation parameter R = 2.2, magnetic parameter M = 4.8, Casson parameter β = 0.4, t = 0.2, Gr = 4, Gm = 7, K = 1.5 and P r = 0.7.

The energy generation from the fossil fuels results to emit a tremendous amount of carbon dioxide into the atmosphere. The rise in the atmospheric carbon dioxide level is the primary reason for global warming and other climate change problems for which energy generation from renewable sources is an alternative solution to overcome this problem. However, the renewables sources are not as reliable for the higher amount of energy production and cannot fulfil the world’s energy demand; fossil fuels will continue to be consumed heavily for the energy generation requirements in the immediate future. The only possible solution to overcome the greenhouse gas emission from the power plant is by capturing and storing the carbon dioxide within the power plants instead of emitting it into the atmosphere. The oxy-fuel combustion power cycle with a carbon capture and storage system is an effective way to minimize emissions from the energy sectors. The oxy-fuel power cycle can reduce 90–99% of carbon dioxide emissions from the atmosphere. Moreover, the oxy-fuel power cycles have several advantages over the conventional power plants, these include high efficiency, lesser plant footprint, much easier carbon-capturing processes, etc. Because of these advantages, the oxy-fuel combustion power cycles capture more attention. In the last decades, the number of studies has risen exponentially, leading to many experimental and demonstrational projects under development today. This paper reviews the works related to oxy-fuel combustion power generation technologies with carbon capture and storage system. The cycle concepts and the advancements in this technology have been briefly discussed in this paper.

As CO2 is emerging as an environment friendly working fluid its applicationin high temperature engine’s waste heat recovery systems is found to bemore suitable than other hydrocarbons. This paper presents a performancecomparison of two systems based on transcritical Rankine cycle using CO2as working fluid. A heavy-duty truck is opted for analysis in which coolantis used to preheat CO2 and further the engine exhaust is used to transferthe heat to main heater. The System-1 and System-2 having single and dualloop based transcritical Rankine cycle are analysed. The independent param-eters taken for the investigative analysis are turbine inlet temperature (TIT),pressure ratio and effectiveness of heat exchangers. Comparison results showthat System-2 is producing 11.8 kW more power than system-1 at 12 MPapressure ratio and at 489◦C TIT. However, under same conditions, system-1 ishaving 16.88% of thermal efficiency which is higher than system-2 by around3%. Further, the Engine coolant utilization rates when compared are nearlysame in both the systems, the exhaust gas utilization rate came out higherfor System-2. In respect of exergy destruction, system-1 shows maximumdestruction in regenerator and System-2 in heater-2.

Nowadays intelligent system application is helpful to increase the mushroom cultivation. Mushroom flourishes in low temperature and high relative humidity atmosphere. Mushrooms fall under the category of fungus, and it is high protein food. Due to this property, it is one of the profitable agriculture cultivation businesses. But mushroom growth of cultivation is depending on specific environmental conditions. Hence, we have developed an automated system that could support the cultivation of several types of edible mushrooms. So in this research work, we are proposing fuzzy-based decision system to increase the cultivation growth of mushroom. In this work, a fuzzy logic controller system is proposed that is developed in MATLAB software. In that Fuzzy controller, moderate the sprinkler system according to temperature, CO2 concentration level, and humidity which is the favorable growing condition for the mushroom.

Nonrenewable sources of energy are depleting rapidly as the ratio of their consumption is higher than its reproduction as it takes millions of years to replenish, high demand, and utilization in agriculture and industries have affected the environment drastically. To fulfill the growing demand and necessity of energy for the continuous process of production and manufacturing promoted the use of renewable sources of energy, but renewable sources of energy need more development to be used with its full potential despite its massive availability. Fortunately, evolution in artificial intelligence has conferred scientists and developers to come up with several methods and improvements in the effective, efficient, and optimized usage renewable energy sources. This paper explores the areas of machine learning application for the effective harnessing of renewable energy sources such as wind energy, geothermal energy, solar energy, and wave energy.

Hybrid electric vehicles are gaining popularity nowadays due to their superior fuel efficiency and benefits to the environment. As such a clear thermodynamic study on the hybrid vehicles in order to further improve the efficiency/fuel economy of the vehicle. This paper studies the effect of a vapor absorption cooling system for cabin cooling purposes. The heat required for the powering of the generator was taken from a low-grade heat source, from waste heat. Since the waste heat from the battery is insufficient for powering a cooling system, the heat from the exhaust was used. This is a low-grade heat source. A lithium-bromide (Li-Br-H2O)-based vapor absorption system is used for the work as this has better output from a low-grade heat source. A waste heat output of 14.2 KW is generally available under city conditions. The thermodynamic analysis of the proposed system was performed, and under this, a coefficient of performance of 0.721 was observed. The thermodynamic first law is used to analyze the effects of various input parameters. Input parameters considered for the analysis are the mass flow rate of the pump, the input to the generator, input to the evaporator. The system was found to be a feasible option in increasing the performance of a hybrid electric vehicle.

The present paper is an investigation of the effects of different operating parameters on the performance of the basic and inlet-air cooled gas turbine gas cycle. The cooling technique adopted for inlet air is evaporative cooling. Thermal efficiency, work output, compressor work has been chosen as some output parameters while turbine-inlet-temperature, pressure ratio, and ambient temperature are the input variables. The results have been plotted in terms of meaningful graphs. The study reveals that as TIT and pressure ratio is increased, thermal efficiency and net-work output increases and the evaporative cycle has a higher efficiency (variance ~1–2.5%) in comparison to the basic cycle. Also, thermal efficiency was observed to be higher at lower ambient temperature values i.e. nearly 288.15 K, and lowers as the ambient temperature is increased. The highest gas turbine net-work output for inlet air evaporative cooling technique has been observed to be 224.80 kJ/kg of air (rpc = 8, TIT = 1100 K) as well as the highest gas turbine efficiency is found to be ~46% (rpc = 16 and TIT = 1100 K).

Connectivity in rural areas is a key aspect of its holistic development. Rural roads are low traffic volume roads. In this paper, study has been done on the construction methodology of rural roads using local resources i.e., local labour, local materials etc. Locally available stones, cobbles, plum etc. have been used with concrete mix. This study throws light on three types of rigid pavements which follow the evolution of Roman road construction methods. These are Cobblestone pavements (CSPs), Plum Concrete pavements (PCPs) and Unreinforced Concrete pavements (UCPs). This paper discuss about the materials used and the construction methodology of all these three types of rigid pavement. The paper also presents an outline of locally available materials which helps in reducing the overall cost of construction of pavements