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The operating temperature of the photovoltaic (PV) cell is essential in converting the renewable radiant energy emitted by the sun into direct current to meet various energy demands. It should be remembered that the photovoltaic efficiency and temperature of the solar PV cell are indirectly proportional. The performance of the PV module can be greatly enriched by minimizing the operating temperature of the semiconducting PV cells, and this is accomplished by removing the surplus heat from the PV module. This paper proposes a novel sandwich- glazed photovoltaic (SGPV) module as an alternative to the standard PV module for overheating protection and assessment of the photovoltaic, thermal, and overall efficiency of the sandwich-glazed photovoltaic thermal (SGPV/T) system. Effects on photovoltaic efficiency and temperature distribution in the SGPV/T system and the standard PV module are also compared. Furthermore, the programmed electrical and thermal models are simulated using MATLAB for comparative analysis. Experiments were conducted in India under the climatic conditions prevailing at Coimbatore (latitude: 11.10ºN; longitude: 76.96ºE). Subsequently, the performance and outlet water temperature of the SGPV/T system are significantly improved with an average photovoltaic, thermal, and overall efficiency of 9.67, 41.34, and 66.78%, respectively. [ABSTRACT FROM AUTHOR]

Large-scale secondary data show that water access is improving in Indian slums; however, women still need to procure water from multiple sources. Based on field research conducted in Coimbatore, Tamil Nadu, this paper examines the everyday negotiations that urban women from slums undertake at different water sources. The study finds that women depend on street taps, water vendors, water tankers, and in-house connections in varying degrees. The results show variation in negotiations that women engage in at multiple sites and sources. These variations have emerged as a result of the characteristics of the water sources and household-level water storage capacity. [ABSTRACT FROM AUTHOR]

Mulberry is an important food plant for domesticated silkworm (Bombyx mori L.). Among several root rot diseases reported in mulberry, black root rot caused by Lasiodiplodia theobromae has now emerged as a major disease. The survey was conducted and black root rot incidence was found to be maximum (51.7%) in Coimbatore district and minimum (14.1%) in Erode district. On PDA, L. theobromae covered Petri plate within three days with cottony white fluffy and slowly turned to black colour. All the four isolates were identified by molecular characterisation through PCR with ITS region and sequences were deposited in NCBI database. Among biocontrol agents screened, Trichoderma asperellum TRI 15 and T. virens TRI 37 were found to be inhibitory with 67.7% and 66.6% reduction in mycelial growth. Five mulberry varieties were screened, variety G2 showed resistance and V1 was highly susceptible. [ABSTRACT FROM AUTHOR]

Mapping and quantifying above ground carbon (AGC) Stocks reflect significant dynamics in the terrestrial carbon cycle and cascade climate change. Estimation of such key driver was performed for the dominant species (Bamboo, Eucalyptus and Teak) over Coimbatore and Nilgiris Biosphere (2006 − 2018 quadruple interval) of Tamilnadu, India with the developed global stepwise multiple linear regression (SMLR) and local geographically weighted regression (GWR) models using multi-dynamic variables. Evapotranspiration (ET) developed using Mapping Evapotranspiration at High Resolution with Internalized Calibration (METRIC) model for the region was analysed with the best-fitted AGC estimation model to understand AGC—ET synergistic pertinence dynamics. The study compared and validated the estimation by the models and indicated that AGC estimation using SMLR exhibiting a high degree of accuracy ( R 2 = 0.84 , RMSE = 5.67 , MAE = 4.61 Mg ha − 1 ) with nominal negative bias in the estimation ranging from 0.13 − 146.34 Mg ha − 1 with amplification of 1.87 ± 1.2 % year − 4. GWR prediction indicted positive bias with comparatively least mean accuracy ( R 2 = 0.59 , RMSE = 13.72 , MAE = 12.85 Mg ha − 1 ). The ET—AGC reciprocity for the dominant species resulted that, bamboo with lower AGC ∼ 25 Mg ha − 1 correlated with higher ET ∼ 3 mm day − 1 tailed by teak with higher AGC ∼ 45 Mg ha − 1 and ET ∼ 2.5 mm day − 1 and eucalyptus with relatively higher AGC and lower ET ∼ 50 Mg ha − 1 and ∼ 3 mm day − 1 , respectively. The analysis resulted in minimal biasness in AGC mapping using SMLR, and both the model signifies that the region can potentially be considered a long-term carbon sink. [ABSTRACT FROM AUTHOR]

Coimbatore is one of the industrial cities in Tamil Nadu, India, which has been experiencing rapid urbanization and population growth. Coimbatore is also known for its unique freshwater lakes environment and serves as a rich ecosystem. However, the assessment of heavy metal levels in aquatic environments is limited. This study was aimed to investigate physicochemical parameters, heavy metals level and sources, and ecotoxicity in sediments collected from five different lakes in Coimbatore. The concentrations of heavy metals (Cr, Cu, Zn, As, Cd, and Pb) in sediments were determined by Inductive Coupled Plasma-Mass Spectroscopy (ICP-MS). Hg level was measured using Advanced Mercury Analyzer (AMA). The determined heavy metal concentrations in sediments varied significantly according to the lake location and consistent with local human linked anthropogenic activities. The metal concentrations in urban lakes were exceeding both the Sediment Quality Guidelines (SQGs) and the probable effect levels" (PELs) mostly; e.g., in sediments from the Lake Ukkadam, the values of 5.08 and 203.32 mg kg-1 dry weight were observed for Hg and Cu, respectively. The ecotoxicity test with ostracods exposed to the sediment samples revealed that mortality ranged between 6 and 23% for countryside lakes and 28 and 88% for the lakes within urban Zone. We used Spearman rank-order correlation and Principal components analysis (PCA) to assess the sources of pollutants and if they related to anthropogenic pressure and eutrophication of lakes. The main sources of heavy metals from studied lakes differed significantly. Urban and industrial effluents were dominant sources in urban lakes. Agricultural runoff, domestic wastes, and natural weathering were responsible for the metal sources in country lakes. This study provides baseline information on the heavy metal pollution status of sediments in the freshwater lakes in Coimbatore, which will be useful for pollution control measures to prevent possible metal sources on these lakes and impose appropriate management practices and continuous monitoring by relevant authorities. [ABSTRACT FROM AUTHOR]

Rapid growth of the urban population, particularly in developing countries, places an enormous pressure on water. Sewage farming is common in all urban areas in India. This study is an attempt to evaluate the effect of diluted sewage wastewater irrigation on cultivation of Eleusine coracana and Zea mays from selected semi-urban and rural areas of Coimbatore, Tamil Nadu. For this, parameters analyzed were water/soil quality, crop quality, and mineral analysis including heavy metal composition and in vitro antioxidant potential. From the results, the physicochemical parameters of both rural and semi-urban wastewater samples are within the permissible limits according to the WHO. In mineral analysis, the heavy metals such as Pb, Fe, and Zn are high in all samples and Ni, Cr, and Cu are within the permissible limits in rural samples but slightly high in semi-urban samples. The proximate composition provides general overview of the nutritional value of a food. E. coracana and Z. mays samples collected from rural area show adequate mineral profile required for growth and nutrition. Both the samples show significant antioxidant values significant at p < 0.05. The results demonstrated that the diluted sewage wastewater has physicochemical properties for safe irrigation. Micronutrient and heavy metal contents in the plant samples were not extremely high and were within the range of FAO/WHO standards. [ABSTRACT FROM AUTHOR]

Cement manufacturing is a process that results in the emission of significant quantities of suspended particulate matter (SPM) to the ambient air. An environmental forensic investigation was carried out in the surroundings of a major cement manufacturing unit at a place called Coimbatore in the southern Indian state of Tamil Nadu. The investigation was carried out to identify the contribution of the cement manufacturing unit to the SPM concentration of the surrounding air environment. The sampling points' selection and sample collection were done following the principles outlined in the INTERPOL Manual for Pollution Crime Forensic Investigation. On-site monitoring of the air samples was carried out using Mini Laser Aerosol Spectrometer (GRIMM, Mini-LAS Model 11R). The instrument was capable of measuring particles ranging from 0.25 to 32 µm and classifying them into 31 size channels. The test results at majority of the monitoring locations were well above the limits specified in the National Ambient Air Quality Standards of India. Microscopic studies of the dust samples were carried out for surface texture and particle shape. The spatial distribution of particles was analysed using geographic information system (GIS) for the visual identification of the extent of the pollution by keeping the cement factory as the focal point. The results from the GIS and microscopic analysis established the role of the cement factory in the particulate matter pollution of its surroundings, specifically in the areas North-West of the factory. The successfully adopted procedure can serve as a guideline for the environmental forensic investigation of similar pollution incidences. [ABSTRACT FROM AUTHOR]

A potculture study was conducted in soils collected from long-term fertilizer experiment (LTFE) being kept up as far the past 40 years to determine whether arbuscular mycorrhizal fungus (AMF) Rhizoglomus intraradices colonization changes the active and passive pools of carbon in a maize (Zea mays) - finger millet (Eleusine crocana)- cowpea (Vigna sinensis) cropping sequence in the Experimental Farm of the Tamil Nadu Agricultural University, Coimbatore, India. Soil samples were processed, sterilized and maize plants were grown in various fertility gradients in the absence (M-) or presence (M+) of AMF (Rhizoglomus intraradices) inoculation. The data have clearly shown that M+ soils had consistently higher active pools such as water soluble carbon, hot water soluble carbon and biomass carbon (M- 189; M + 305 mg kg−1), and passive pools such as soil organic carbon (M- 4.17; M + 4.31 mg g−1) and total glomalin. Among the fertility gradients, 100% NPK + Farm Yard Manure (FYM) with or without mycorrhizal fungal inoculation registered higher values for both active and passive pools of C but the response was more pronounced in the presence AMF inoculation. Overall, the data suggest that mycorrhizal fungal inoculation assists in effective carbon sequestration in an intensive cereal-legume cropping system.Abbreviations: AMF: Arbuscular mycorrhizal fungi; DAS: Days After Sowing; LTFE: Long-Term Fertilizer Experiment; WSC: Water soluble organic carbon; HA: Humic acid; FA: Fulvic acid; HWSC: Hot water soluble carbon [ABSTRACT FROM AUTHOR]

Chromium-resistant plant growth-promoting bacteria (PGPB) were isolated from the electroplating industry waste disposal site soils at Coimbatore, India, using LB medium. The strain tolerated chromium concentrations up to 500 mg Cr6+L−1on LB medium. The strain was identified as Pseudomonas sp. VRK3 based on its morphological, physiological, and biochemical characteristics following Bergey's manual of determinative bacteriology. Evaluation of plant growth-promoting parameters revealed the intrinsic ability of the strain for the production of indole-3-acetic acid (IAA), siderophore, and solubilization of insoluble phosphate. Pseudomonas sp. VRK3 utilized tryptophan as a precursor for the growth and production of IAA (105.77 μg mL−1) and also exhibited the production of siderophore. The strain utilized tricalcium phosphate as the sole source of phosphate exhibiting a high rate of phosphate solubilization (0.49 μg mL−1). Pseudomonas sp. VRK3 showed a significant extent of chromium uptake and accumulation in their cell walls. Furthermore, Pseudomonas sp. VRK3 was demonstrated to possess mobilization of chromium from the soil that would enhance chromium availability to the plant. Potential use of this Pseudomonas sp. VRK3 as PGPB needs further testing in enhancing the growth and chromium uptake by the plants in pots under nursery conditions. [ABSTRACT FROM AUTHOR]

Haphazard urbanization and unprecedented vehicular growth that exacerbate air quality are prevalent features in India. Coimbatore, an important industrial city ranking 15th in terms of principal urban agglomerations of India, was classified as a moderately polluted area in National Ambient Air Quality Monitoring survey in 1997. The current study (March 1999–February 2001) was undertaken to assess suspended particulate matter (SPM) in urban and suburban Coimbatore. It was found that in the Coimbatore atmosphere SPM with a diameter of less than 10 µm (respirable fraction, RSPM or PM10) and those with a diameter above 10 µm, the non-respirable (NRSPM) fraction, ranged between 30–149 µg/m 3 and 24.4–460 µg/m 3 respectively. The study infers that urban areas, especially those with frequent vehicular traffic and traffic congestion, had comparatively high RSPM exceeding the Indian prescribed standards (60 µg/m 3 ). Emission inventory estimated for current vehicle strength showed that about 840 000 kg of particulate matter was emitted during 2001. Wind speed negatively correlated with RSPM, while it was positively correlated with NRSPM. Temperature had a negative correlation with RSPM values. [ABSTRACT FROM AUTHOR]