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Release of potentially persistent, bioaccumulative and inherently toxic chemicals into the environment may cause adverse effects to plants and animals. Hundreds of thousands of chemicals are manufactured each year and experimentally assessing them for these parameters is costly, time consuming and requires animal testing. To address these concerns there has been a paradigm shift in adoption of computational chemistry and toxicology methods for assessing environmental risks posed by such chemicals. These computer-based methods harness the power of fast processors, high speed internet, statistical methods, and curated toxicological databases to fulfil this need. In this work a summary of selected publicly available computational models and databases is presented. Global regulatory agencies apply these predictive models to support their decisions. Indian regulatory bodies too could benefit from this exercise in identifying chemicals of ecotoxicological concern and in taking an appropriate regulatory decision thereby protecting the environment.&nbsp

Pollution load, rising population, and scarcity of water have drawn special attention for the management of water resources such as pond water. The present investigation was carried out at Dulahra and Ved ponds in Ratanpur, Bilaspur District. The seasonal deviations in water such as transparency, temperature, pH, dissolved oxygen, nitrate, phosphate, biological oxygen demand (BOD), total dissolved solids (TDS), and total suspended solids (TSS) were evaluated. In the contemporary study, the BOD standards were considerably higher than World Health Organization (WHO) standards (5 mg/l). The water samples were collected from each site at outer (about 100-150 meters) and internal (10 m from the shoreline) localities. The highest mean value of BOD, i.e., 32±4.6, was found at the north peripheral S-1 in the summertime. In the summer season, maximum mean BOD 39±2.1 was found at S-2 (West peripheral) in Ved Pond. It indicates the biological pollution load on the water body in the site of North peripheral in Dulhara pond and West peripheral in Ved Pond in the summer season. Low Secchi depth readings such as 20±1.0 at S-2 North peripheral site during summer seasons are indicative of reduced water clarity that is habitually related to the existence of suspended particles and algal tinges. We also found the maximum value of total suspended solids on the north side of the pond, where the transparency of water was also very low. A transparency value of 37.0±0.40 was noted at S-1 in the East marginal sites and 30±0.22 at the East inner sites in the rainy period at the Ved pond. The transparency of the water physique is exaggerated by the elements like planktonic growth, rainfall, the sun’s location in the sky, the angle of incidence of rays, cloudiness, electiveness, and turbidity due to deferred inert particulate material. Our outcomes suggest that the lowermost water transparency value was 16.0 ± 0.41 at S-1 in the North marginal sites for the duration of summer. The concentration of Calcium ions was much above the WHO recommended value of 75 mg/l at almost all the sites and both ponds during the study period. Numerous indicators and catalogues have been established in this particular study to evaluate water quality in intermediate water bodies. For transparency studies,low-cost Secchi disk was used.

In this chapter, we focus mainly on the constant development of technology and scientific knowledge that supports and solve necessities in our society. Therefore, researchers have been continuously trying to develop a better world around us by increasing the properties of materials that can be used in industries in more efficient and better ways. The detailed mechanism and challenges of luminescence materials in photocatalysis followed by the effect of rare-earth metal doping in inorganic phosphors are further utilized in the field of photocatalysis. More important points are mechanism and challenges of luminescence nanophosphors for photocatalysis discussed in this chapter. This follows the synthesis and characterization of inorganic nanophosphor materials and their properties used in photocatalysis. The chapter also contains discussion about nanophosphor material applications in water purifications and hydrogen generation mechanisms. Finally, we provide our conclusion with future scope in this field.

LaBO3:xDy3+ (x = 0.05 mol%, 0.1 mol%, 0.2 mol%, 0.5 mol%, 1 mol% and 2 mol%) phosphors were synthesized by solid-state reaction method. X-ray diffraction technique was used to confirm the formation of compound. Photoluminescence emission spectra shows two emission peaks at 470 nm and 575 nm when excitation wavelength is set at 352 nm. Photoluminescence intensity increases upto 1 mol % of Dy3+ and then starts decreasing. Dipole-dipole interaction is found to be responsible for concentration quenching of photoluminescence intensity. Commission Internationale de I’Eclairage (CIE) chromaticity diagram demonstrates that the phosphor emits in bluish white region of the visible spectrum. Critical energy transfer distance between dopant ions was determined. The mechanoluminescence characteristics were studied by the impact method. The peaks of both the mechanoluminescence (ML) intensity and the total ML intensity of the UV exposed phosphors increases with increasing impact velocity for 1 mol % concentration of Dy3+. The ML sensitivity of the LaBO3:Dy3+ (Dy3+ = 1 mol %) phosphor is comparable with the reported ML of various inorganic phosphors. The thermoluminescence characteristics of the samples were also investigated. Thermoluminescence glow peaks were recorded with 480 Gy, 80 Gy and 20 Gy dose of γ-irradiation from Co60 Source. TL trapping parameters were determined by Chen’s peak shape method and glow curve deconvolution method. LaBO3:Dy3+ phosphors were found to be good mechanoluminescent materials and can be used in stress sensing application.

The present work aims at analysing the water quality index (WQI) in the Dulahra pond water situated in Ratanpur city in Bilaspur District in Chhattisgarh by monitoring four direction [north, west, east south ]in sampling locations around the Dulahra pond for a period of 3 months from September to November-2018. For calculating the WQI, 14 parameters, namely, pH, electrical conductivity, total dissolved solids, Total suspended, Total Hardness Alkalinity, Dissolved oxygen, BOD, COD. Nitrates fluoride and transparency were analysed. It is apparent from WQI values that Dulahra pond water with WQI values ranging from 62.28 to 69.84(pre-immersion period), 58.27to 64.16(immersion period) and 38.27to 44.16 (post-immersion period falls under simply good to poor water category. It was observed that the values of physicochemical parameters decrease in the pre-immersion and immersion period, and significantly increased during the immersion period for pH, total dissolved solids, Total Hardness, Alkalinity, COD , Nitrates however the general trend observed was: Immersion > Post immersion > Pre-immersion values. The present work showed maximum values found during Post immersion period for EC,BOD, Chloride, fluoride Sulphate,. (Post immersion > immersion > Pre-immersion values ) The present study revealed that Dulahrapond water is polluted due to immersion of idols of God and Goddess during festival season ,human activity ,surface run-off, bathing activities, agriculture run-off, effluents from upstream from surrounding industrial and garden area, immersion of idols of God and Goddess during festival season, and is unsuitable for human consumption, industrial purpose also for the survival of life forms unless treated properly. The low value of DO and BOD and Total Solids levels at different sites indicate the poor water quality due to idol immersion.

LaBO