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691.
The paper presents the novel design of double glazing helical coil solar cavity receiver for solar thermal applications. Performance model has been developed for the experimental setup based on energy balance equations. The results obtained were compared with horizontal tube receiver for the same experimental setup. The result shows that the 87.96% improvement in the convective heat transfer coefficient for the double glazing helical coil solar cavity receiver. Maximum conversion efficiency achieved is 21% more than that would be obtained for horizontal tube receiver. This paper also investigates how the quality of vacuum degraded with the temperature of the glass cover. 相似文献
692.
Srivastava Tapendra Kumar Singh Pushpa Verma Ram Ratan 《Environment, Development and Sustainability》2022,24(3):3588-3618
Environment, Development and Sustainability - Weather variability over the long run exhibits the trends of change in climate and forewarns for development and deployment of adaptation measures.... 相似文献
693.
Sahoo Amiya Kumar Behera Hari Charan Behura Ajit Kumar 《Environment, Development and Sustainability》2022,24(10):12248-12262
Environment, Development and Sustainability - Health has been a focal point in sustainable development policies. Seventeen new goals of sustainable development contribute directly or indirectly to... 相似文献
694.
V. Deepesh Virendra Kumar Verma K. Suma Swathi Ajay A. Gnanavelu M. Madhusudanan 《Journal of Material Cycles and Waste Management》2016,18(2):273-286
This study investigated the feasibility of using fresh activated sewage sludge as inoculum for the microbial valorization of segregated municipal solid waste and evaluated the quality of organic soil amendment generated. Organic fraction of municipal solid waste, which consisted of vegetative (vegetable, fruit and flower) wastes was seeded with activated sewage sludge and processed by rapid aerobic microbial treatment. Efficacy of microbial valorization process and quality of final product were assessed by physico-chemical analysis. Suitability of final product was assessed with regard to heavy metal content, pesticide residues, microbiological quality and phytotoxicity. Quality of the soil amendment generated was compared with the control product generated with a commercial microbial inoculum. Phytotoxicity experiments indicated the stimulatory effect of sewage sludge seeded soil amendment on plant growth but inhibition was observed in closed growth test due to the evolution of gaseous phytotoxic agents. The study suggests that segregated municipal solid waste can be effectively valorized with activated non-dewatered sewage sludge as inoculum and the quality of soil amendment generated was comparable to compost intended for unrestricted applications. 相似文献
695.
Dipesh Kumar Ravi Bhushan Kalyan Chatterjee 《International Journal of Green Energy》2018,15(3):208-221
The frequency deviation and power fluctuation need to be controlled in a wind-integrated power system (WIPS) for keeping the balance between system power generation and demand, which support the quality and stability of overall power system. The present paper addresses this problem while concerning the integration of intermittent wind power and load disturbance into the WIPS. With this intent, it proposes the compensated superconducting magnetic energy storage (CSMES) system with proportional integral derivative (PID) controller for improving the frequency and power deviation profile. A novel swarm intelligence-based artificial bee colony (ABC) algorithm is used for optimal design of PID-CSMES system. Robustness of the proposed ABC-based PID-CSMES control strategy is tested in WIPS under various disturbance patterns of load and wind power. To demonstrate the improved dynamic response, their simulation results are compared with particle swarm optimization-based PID-CSMES, PID with SMES, and only PID controller technique. The performance indices and transient response characteristics of frequency and power deviation are used to evaluate and compare the accuracy and efficiency of each controller. Stability of various system configurations is analyzed using eigenvalue location. Comparing the results of different controller in WIPS indicates a substantial improvement in the dynamic response of system frequency and power deviations by utilizing the proposed control strategy. 相似文献
696.
S. Shiva Kumar S.U.B. Ramakrishna B. Rama Devi 《International Journal of Green Energy》2018,15(10):558-567
PEM water electrolysis is one of the most efficient methods for the production of hydrogen because of produced high purity of the gases and environmentally friendly. In the present study, Phosphorus-doped Graphene (PG) was synthesized by thermal annealing of triphenylphosphine (TPP) and graphene oxide (GO). The PG supported palladium (Pd/PG) electrocatalysts were synthesized by chemical reduction method and used as the cathode for hydrogen evolution reaction (HER) electrode. Structural properties and electrochemical performances of the synthesized Pd/PG electrocatalyst were studied by FE-SEM, EDS, ICP, FT-IR, XRD, and Cyclic voltammetry (CV) methods, respectively. The membrane electrode assemblies (MEA’s) were fabricated using Pd/PG as cathode for HER electrode and RuO2 as anode for OER electrode. Also, their electrochemical performances along with the corresponding hydrogen yields were evaluated in single cell PEM water electrolyzer at various experimental conditions such as different current densities from 0.1 to 2.0 A cm?2 and temperatures (28–80°C). The synthesized Pd/PG electrocatalyst was observed a current density of 1 A cm?2 with 1.95 V at 80°C. Further, long-term stability studies were carried out continuously up to 2000 h which showed a reasonable stability. Hence, the synthesized Pd/PG can be used as an alternative to Pt-based electrocatalysts for the HER in PEM water electrolysis. 相似文献
697.
Randhir K. Bharti Dolly W. Dhar Radha Prasanna Anil Kumar Saxena 《International Journal of Green Energy》2018,15(1):45-52
Generation of biodiesel from microalgae has been extensively investigated; however, its quality is often not suitable for use as fuel. Our investigation involved the evaluation of biodiesel quality using a native isolate Chlorella sorokiniana MIC-G5, as specified by American Society for Testing and Materials (ASTM), after transesterification of lipids with methanol, in the presence of sodium methoxide. Total quantity of lipids extracted from dry biomass, of approximately 410–450 mg g?1 was characterized using FTIR and 1H NMR. After transesterification, the total saturated and unsaturated fatty acid methyl esters (FAMEs) were 43% and 57%, respectively. The major FAMEs present in the biodiesel were methyl palmitate (C16:0), methyl oleate (C18:1), and methyl linoleate (C18:2), and the 1H NMR spectra matched with criteria prescribed for high-quality biodiesel. The biodiesel exhibited a density of 0.873 g cm–3, viscosity of 3.418 mm2 s?1, cetane number (CN) of 57.85, high heating value (HHV) of 40.25, iodine value of 71.823 g I2 100 g?1, degree of unsaturation (DU) of 58%, and a cold filter plugging point (CFPP) of –5.22°C. Critical fuel parameters, including oxidation stability, CN, HHV, iodine value, flash point, cloud point, pour point, density, and viscosity were in accordance with the methyl ester composition and structural configuration. Hence, C. sorokiniana can be a promising feedstock for biodiesel generation. 相似文献
698.
Rajesh Kumar 《Environment, Development and Sustainability》2016,18(1):187-196
Distillery effluents, a major by-product of distilleries are a major environmental hazard as they are rich in organic matter, micro- and macroelements. Management of this enormous amount of nutrient-rich effluent and its effective utilization is a major challenge. These effluents can be used as a source of nutrient by C4 crops like sugarcane and subsequent ratoon crops under fertigation system. Impact of fertigation in sugarcane-ratoon cropping system on soil microbial biomass is important as the microbial population plays an important role in the nutrient and biogeochemical recycling. Keeping this in mind, a field experiment was carried out in the sandy loam soil of semi-arid to humid sub-tropical climate of Gajraula (28.85°N, 78.23°E) region, India with different doses of diluted and undiluted effluent for fertigation of sugarcane crop in presence and absence of 50 % recommended dose of fertilizers with suitable replicates. Two post-sown irrigations with four times diluted effluent gave the maximum yield in case of sugarcane crop. Taking into consideration the yield and the culturable microbial population sizes, it can be concluded that one to two post-sown irrigations with diluted effluent can be used to enhance soil fertility in terms of microbial population and to enhance sugarcane and ratoon crop productivity. This package is economically viable and can also take care of distillery waste management and reduction in consumption of chemical fertilizers by 50 %, a key for sustainable agricultural development. 相似文献
699.
Vineet Kumar Praveen Guleria Surinder Kumar Mehta 《Environmental Chemistry Letters》2017,15(2):165-177
Food toxins are produced as defense tools by microorganisms that use nutrients for their growth. Microorganisms thus spoil food, taste and can infect humans, sometimes leading to death. Food adulteration and brand protection are also major issues in the food industry. Here we review the use of nanomaterials for sensing food quality. Nanosensors can detect pathogenic bacteria, food-contaminating toxins, adulterant, vitamins, dyes, fertilizers, pesticides, taste and smell. Food freshness can be monitored using time–temperature and oxygen indicators. Product authenticity and brand protection can be assessed using invisible nanobarcodes. Overall, nanosensors with unique properties are improving food security. 相似文献
700.
Dhananjay Kumar J. P. Gaur 《Environmental science and pollution research international》2014,21(17):10279-10285
The present study explores the tolerance and metal removal response of a well-developed 2-week-old Phormidium mat after long-term exposure to Cu2+-enriched medium. Cu2+ enrichment inhibited increase in mat biomass in a concentration-dependent manner. Mat area and the number of entrapped air bubbles decreased as Cu2+ concentration increased in the medium. Decrease in number of air bubbles obviously reflects the adverse effect of Cu2+ on photosynthetic performance of the mat. Metal enrichment did not substantially alter the amount of pigments, such as chlorophyll a, chlorophyll b, carotenoids, and phycocyanin, in the mat. Enhancement of Cu2+ concentration in the medium led to changes in species composition of the test mat; however, Phormidium bigranulatum always remained the dominant organism. Relative share of green algae and some cyanobacterial taxa, namely, Lyngbya sp. and Oscillatoria tenuis, in the mat were increased by Cu2+ enrichment. The mat successfully removed 80 to 94 % Cu2+ from the growth medium containing 10 to 100 μM Cu2+. Extracellular polysaccharides, whose share increased in the mat community after metal addition, seem to have contributed substantially to metal binding by the mat biomass. 相似文献