There is a pressing need for new nanomaterials for multipurpose functions. The biological synthesis of nanoparticles is environment-friendly, least toxic, and cost-effective. An experiment was designed to use extracellular amylases in the cell-free filtrate (CFF) for the biosynthesis of silver nanoparticles (AgNPs) from the Trichoderma harzianum MTCC 801 strain. Potato dextrose broth (PDB) as general-purpose growth media and amylase production media (APM) as enzyme-specific production media have been used for sub-merged fungal cultivation and nanoparticle synthesis. AgNPs synthesized in the CFF of PDB were compared with AgNPs synthesized from the CFF using APM. The cell-free filtrate obtained upon enzyme stimulation has contributed to the reduction and capping process of nanosilver. The synthesized AgNPs showed a spectral peak at 420 nm, a characteristic feature of AgNPs. The particles were monodispersed, 50 nm in size, and spherical in shape as well as have shown an antifungal effect (100% inhibition) against Sclerotinia sclerotiorum MTCC8785. This is the first report to synthesize trichogenic AgNPs using extracellular amylases against the phytopathogen Sclerotinia strain.

The present work investigates the efficiency of Paecilomyces variotii upon degrading Reactive Black dye which has been termed a recalcitrant variety of synthetic dye. In this research, initially a predominant fungal species, Paecilomyces variotii was isolated from the tannery effluent sample. The study was carried out by assessing the ability of fungi to decolorize the dye under various parameters like pH (5,7 and 9), Temperature (7°C, 30°C, and 45°C), Dye concentration (200, 300, and 400 mg/L) for different incubation or exposure time interval (3, 5 and 7 days). From the experimental study, it was found that Paecilomyces variotii showed a maximum percentage of dye decolorization at 7°C at pH 9 with 75%, at 30°C at pH 7 with 85%, at 45°C at pH 5 with 82% and a maximum period of incubation with 7 days in 200 mg.L-1 concentration. This result conveys that the strength of Paecilomyces variotii in decolorizing the synthetic dye is effective at a moderate temperature with neutral pH for maximum exposure time. So Paecilomyces variotii could be a good candidate of choice for the biodegradation of various synthetic dyes when manipulated wisely. Also, the result sparks a positive attribute toward decreasing industrial wastewater pollution.

Wind and temperature measurements at an oil refinery site located southeast of Baghdad city at two levels, 15 and 30 m, are presented. Three schemes are used to determine different stability classifications: Monin-Obukhov length, gradient, and bulk Richardson numbers. Meanwhile, vertical changes in air temperature and wind shear are also computed. There were lapse rate and inversion cases during the nights and days while favorable wind shear was dominant. The variation of stability in each scheme is large, covering the entire range of stability for a given class. The results of stability schemes are compared to each other. The results show that the schemes based on gradient and bulk Richardson numbers reasonably compare them.

This study seeks to understand the socio-economic and ecological impacts of the hydroelectric power projects along the upper basin of the river Teesta in Sikkim. This study estimates the non-market benefits of restoring the Teesta riverine ecosystem and evaluates the transferability of welfare estimates. This study is a first of its kind undertaken in the Teesta basin which uses a unique dataset of 830 households obtained from the affected regions of the river basin. During the study, nine villages adjacent to the river Teesta, dams, and powerhouses were identified and surveyed. Double bounded dichotomous choice questions were used to elicit willingness to pay (WTP). Both the logistic and normal distribution models were fitted and the results were mostly similar. The median WTP was INR 373.00 and the variables that described the rating on dams, ownership of property, monthly expenditure of the household, informal employment status, and satisfaction about the state of the river Teesta were among the significant variables in the model. The benefit function value transfer estimated was INR 232.00 with the percentage transfer error (PTE) of 61.9%.

The requirement for a renewable and environmentally gracious alternative resource of energy has grown in recent years as a result of increased knowledge of the negative impacts of petroleum-based fuels on the environment and the regular rise in crude oil prices. Biodiesel has been proven to be the ideal replacement for diesel because of its unique qualities, such as a huge decrease in greenhouse gas emissions, nonparticulate matter pollutants, non-sulfur emissions, less toxicity, and degradability. This article examines the pre-treatment stage, the physiological and chemical features of WCO, transesterification, esterification, and the manufacturing of biofuel from waste-cooked oil using several techniques and catalyst types. The elements that influence the stated process parameters are investigated, with a particular focus on the methanol to oil ratio (molar ratio), time of reaction, the temperature of the reaction, catalyst percentage, and yield of biodiesel. After the production of biodiesel, we can optimize the process parameters, for example, methanol to oil ratio, the temperature of the reaction, duration of reaction, and catalyst percentage, and also optimize the yield of biofuel generation with the CCD design of the Response surface methodology (RSM) algorithm using Design Expert software.

Taking Zhahan village in Qiongzhong County, Hainan, as an example, and based on its 160,000 tourist arrivals in 2019 and taking into account the real circumstances of Hainan, this research composes the emission models of carbon emissions from tourism transportation, tourism accommodation, tourism catering, other tourism activities and pollutants in this village. The outcomes indicate that Zhahan village's tourism catering consumes the most energy and emits the most carbon, accounting for 53.95% of all carbon emissions. Furthermore, the emission of tourism accommodation is the second, occupying 24.13%. Then, its tourism waste emission is the third, constituting 13.61%. In addition, its annual sewage discharge from tourism activities amounts to 15,144 t. This article promoted 1MW photovoltaic and 10 square solar hot water in the entire village, scientifically developing the evaluation system of rural tourism carbon emission, and making a low carbon brand of emission reduction coupling. The research and operation can be replicated and extended to enable the harmonious development of tourism development and organic unity of energy resource utilization.

Air quality has recently been a huge concern as it directly affects people’s lives. An air quality level assessment and prediction system is essential to keep track of air quality. Therefore, developing an efficient air quality assessment and prediction system has become one of the most important concerns. In the present work air quality level of Surat city, India is assessed and predicted for the period from 2020 to 2023 using the Autoregressive integrated moving average (ARIMA) model. Experimental results show that the ARIMA model outperforms the other models. According to the findings, the maximum quantity of SO2 and NO2 present in the air in 2020 is 37 mm and 18 mm, respectively, with a maximum of 27 mm and 31 mm in 2021. Thus, we can observe that even though SO2 has reduced a bit, the amount of NO2 has increased, thus degrading the quality of air.

The present study evaluated lead biosorption by Enterobacter cloacae WW1 isolated from tannery wastewaters under different initial Pb2+ concentrations, biomass concentrations, and contact times. The results showed that at an initial Pb2+ concentration of 80 mg.L-1, the optimal conditions for living cells were a biomass concentration of 7 g.L-1 and a contact time of 120 min. For non-living cells, biomass was a biomass concentration of 4 g.L-1 and contact time of 45 min, which provided removal efficiencies of 92.03 ± 0.10% and 99.51 ± 0.01%, respectively. The maximum biosorption capacity obtained for non-living cells using an initial Pb2+ concentration of 640 mg.L-1 was 76.65 ± 0.05 mg.g-1. The equilibrium data followed the Langmuir and Freundlich models for living cells, and the data for non-living cell biosorbents fit the Langmuir model. The biosorption kinetics for living and non-living cells fit well with a pseudo-second-order kinetic equation. SEM-EDX analysis clearly showed the morphology and presence of Pb2+ particles on non-living cell surfaces after biosorption. In addition, the results revealed that functional groups such as hydroxyl, amino, carboxyl, amide, and phosphate groups on the bacterial cell surface detected by FTIR were associated with the binding of Pb2+ ions. The results indicated that E. cloacae WW1, a lead-resistant bacterium, can be used as an alternative biosorbent for lead removal from wastewater.

Heating, Ventilating, and Air Conditioning (HVAC) is a system to condition indoor air by cooling or heating to achieve thermal comfort for a human being. The HVAC system operates based on the refrigeration cycle, where heat is dissipated from the condensing unit in the warm air arrangement. This represents an ironic foundation of heat that might be recovered for further schemes or applications. In this paper, experimental work was developed to validate the proposed heat recovery system using heated air released from the condenser unit of the HVAC system as a source for the air dryer for the drying rack. Four different output parameters are to be observed in this research: the dry-bulb temperature of the air exit from the condenser unit, the dry-bulb temperature of the air inflowing the dryer, and the drying time and the relative humidity of the air leaving the dryer. These experimental works were conducted using a domestic application of a 1.0 hp air conditioning (AC) system with R-22 refrigerant gas and based on the following factors: The three-variant mass of wet clothes, the three-stage of mechanical fan speed for releasing warm air from the condenser, and the effect of variable ambient or surrounding air dry-bulb temperature were studied. A physical prototype of the dryer was constructed for proof-of-concept purposes. The experimental output was then analyzed to obtain precision and accurate data. To determine the system behavior, a refrigeration cycle analysis was conducted. It has been shown that an AC system of 1.0 hp can cover wet clothes drying of weights 1950 g, 4255 g, and 6350 g at 55, 80, and 110 min with a constant air velocity of 0.34 m-3.s-1 in an ambient temperature of 33°C. The significant contribution of this research is the proposed heat-recovery-based air dryer system with the capability to increase the Coefficient of Performance (COP) of the AC unit from 2.36 to 2.70. Hence, the energy-saving was received using the heat-recovered-based air dryer instead of a commercial electric air dryer system that uses high power consumption from their heater element.

The goal of this study was to examine the water quality for drinking and domestic purposes in the Korba coalfield region of Chhattisgarh, India. The Korba Coalfield region has seen the collection of fifteen groundwater samples from different places. The content of eight metals was determined using ICP-MS instruments: aluminum (Al), barium (Ba), cadmium (Cd), iron (Fe), magnesium (Mn), lead (Pb), nickel (Ni), and zinc (Zn). Spatial distribution maps were produced using GIS software to make it simple to understand the groundwater’s quality. The groundwater samples were collected during the pre-monsoon season and the amount of Al, Ba, Cd, Fe, Mn, Pb, Ni, and Zn exceeded the ideal drinking water standards in a few sites. The elevated metal concentrations in the study region’s groundwater could be hazardous to the quality of water. The HPI value based on mean concentration was calculated to be 21.64, which is significantly lower than the reference pollutant index score of 100. The HPI calculation revealed that 73.33% of groundwater samples had low HPI values, 6.67% had medium HPI values, and the remaining 20% had high HPI values. The correlation between heavy metals and HPI was calculated; HPI is positively correlated with Fe (r > 0.9471), Pb (r > 0.9666), and Zn (r > 0.9634), indicating that these elements contribute significantly more to heavy metal concentration in the various samples examined than the other selected elements. The box plot seems to be a graphical representation of the outcomes of the different parameter concentrations which show the mean, maximum, and minimum metal values. The cluster analysis was performed and it was classified into two clusters. Cluster-1 comprises 14 members (93.33%) of the water samples examined and is distinguished by relatively low Ba (<700 μg.L-1), pH, TDS, Al, Fe, Cd, Mn, Pb, and Zn concentrations. Cluster-II is made up of 1 member (6.67%), which is primarily made up of groundwater samples (GW-10) taken in the KCF region, India. High values of HPI are found in the eastern portion of Chhattisgarh’s KCF region, reflecting the spatial distribution of metals. Heavy metal leaching from open-pit mining and transit routes was observed to have contaminated groundwater in the eastern section of the research region.