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This article provides information on the technology of obtaining chelated organomineral micro fertilizers based on phosphorus and coal production waste to increase crop yields. The obtained chelated organomineral micro-fertilizers are involved in the structure formation of the soil and eliminate the deficiency of nutrients and increase productivity in the cultivation of crops, also aimed at reducing accumulated industrial waste, which in turn allows you to regulate the environmental situation and partially solve the issue of industrial waste disposal.

The average annual outdoor background radiation dosage across the study area was ∼two times greater than the world average. Higher radiation dosage was observed in indoor environments than outdoors in the majority of the sampling locations.

Graywater reuse is one of the important concepts in attaining water sustainability. A major challenge in this area is to realize various components present in graywater. The present study involves the identification of the chemical components of graywater collected from three different environments and to investigate the efficiency of removal of some of these chemical components using ultrafiltration membranes (polyelectrolyte multilayer (PEM) membranes). The chemical components were analyzed using liquid chromatography connected with quadrupole time-of-flight (UPLC-Q-ToF-MS). A number of micropollutants including surfactants and certain contaminants of emerging concern (CECs) were identified from these samples. Out of 16 compounds identified, 13 were surfactants and the remaining were caffeine, oxybenzone, and benzophenone. These surfactants are mostly the ingredients of various detergents. Low-pressure filtration studies of the collected samples were carried out utilizing chitosan/polyacrylic acid (CHI/PAA) multilayer membranes. A 5.5 bilayer membrane showed more than 95% rejection of the identified compounds in the selected samples and significant improvement in the water quality parameters. This demonstrates that the membrane used in this work is effective in the removal of various chemicals from graywater as well as enhancing the water quality.

Heavy metal based toxicity has a direct relation with the perturbation of protein structure. We have investigated the progressive unfolding of ovalbumin, in the presence of increasing concentration mercury (0–6.25 μM) using different spectroscopic techniques. Formation of amorphous aggregate has been observed at the physiological pH. Initial addition of HgCl2 resulted in the association of monomers to oligomers that proceeded to non-fibrillar aggregates on further addition. The sigmoidal curve obtained from the Stern-Volmer plot clearly divided into three stage transition. A strong lag phase is observed indicating the time dependence for the association of competent monomers. The second stage was resolved into non-cooperative binding. These results match very well with the data from atomic force microscopy and the free energy change observed in the regions. Raman spectroscopic studies indicated toxic antiparallel β-sheets structure. Time dependent atomic force microscopy study revealed the off-pathway nature of amorphous aggregates. At molten globular state, similar quenching behaviour is observed. The atomic force microscopy images clearly indicate at pH 2.2 the initiation of fibril formation occurs at lower concentration of HgCl2 itself. Our results revealed the conformation switch of ovalbumin upon the contact of an environmental toxin and its possible way of toxicity.

An analysis on the presence of uranium in drinking water sources of five districts in Kerala, Southern India has been carried out. 830 Samples from different sources during pre and post-monsoon seasons were subjected to the analysis for uranium and 11 other water quality parameters. The concentration of uranium was found to be varying from

Surfaces of commercially available polyamide membranes were modified by polyelectrolyte monolayer by dip coating method. The formation of monolayered membranes was confirmed by spectroscopic and microscopic methods. The membrane performance is evaluated for the removal of beta blockers (β-blockers) from aqueous solution and resulted in nearly complete (98%) removal. Also, in presence of ions, surfactant and humic acid above 85% of removal was observed. For atenolol (ATL), metoprolol (MPL) and timolol (TML) the rejection was very poor at acidic pH values and from pH 6 onwards nearly complete removal was observed. The removal percentage was unaltered for propranolol (PPL) and labetalol (LTL). A reduction in rejection percentage was observed for PPL (42%) and LTL (17%) respectively as the concentration of the salt increases from 0 M to 0.2 M while the others were almost completely permeated. The adsorbed β-blockers could be desorbed from the membrane (ATL (86%), MPL (93%), TML (83%), PPL (44%) and LTL (32%)). The performance of the membrane was also evaluated by continuously exposing it to the feed solution. The removal was found to be decreasing on increasing the feed volume at steps. The performance was further improved by the inclusion of chitosan/poly(styrene sulfonate) (CHI/PSS) multilayers.

Air quality disturbance zones of the Greater Cochin region (Kerala, India) for the years 2014, 2015, 2016 and 2017 along with air quality assessment and dispersion modelling using in situ measurements and mathematical models, have been investigated in this report. Landsat-8 satellite with OLI and TIRS sensors on board were used for the analysis. The ground based in situ measurements (pollutant parameters) were also obtained from the Kerala state pollution control board. Zonal statistics analysis was performed in various combinations especially air quality disturbance zones with respect to land use/land cover and administrative units for various years. The air quality disturbance zone index (AQDZI) values observed indicated that 38.16% of the study area in 2014 belonged to very good category, 22.94% to good category, 32.37% to moderate category and 6.53% to poor category. In 2015, 56.78% of study area belonged to very good category and 43.221% to good category while in the year 2016 very good category of AQDZI values occupied an area of 45.284% and good category AQDZI values occupied an area of 54.72%. In 2017, 99.834% of the study area belonged to good category and 1.233% to moderate category. Results obtained from zonal statistics revealed that the poor air quality was observed in built up area and good air quality at rubber plantation in all the four selected years. In the case of administrative units, Kochi Corporation experienced poor air quality during all the years studied and Mulanthuruthy grama-panchayath experienced good air quality during most of the years except in 2016.

Pharmaceutical compounds released into the aquatic environment are famed for their persistence in the environment. Advanced oxidation processes (AOPs) are considered as the most efficient technology for the complete degradation and mineralisation of organic pollutants. This study describes an investigation on the degradation of the active pharmaceutical compound, isoniazid (INH), in aqueous medium. This study mainly utilized UV/H2O2 method for the efficient generation of OH for its removal. The degradation was carried out under varying hydrogen peroxide concentration. The effects of the important water matrix such as humic acid, and anions on the degradation efficiency were also investigated in this study. The degradation increases with hydrogen peroxide concentration because of the availability of more hydroxyl radical. The water matrix also had a strong influence on the degradation. The end product analysis was carried out by using high-resolution mass spectrometry. Four products were identified and a degradation mechanism has been proposed.

Protein-ligand binding studies have gained considerable attention owing to its application in biomedical research. The present study discusses the application of spectroscopic and theoretical methods to probe the interaction between a model ligand, 1, 3-diphenylisobenzofuran (DPBF) and bovine serum albumin (BSA). The quenching of the intrinsic fluorescence of BSA arising from tryptophan residue in the presence of DPBF is monitored to follow the nature and mechanism associated with the binding process. The binding affinity and number of binding sites have been investigated. Synchronous fluorescence and UV–Vis spectroscopic studies have been carried out to follow the changes in the fluorophore micro-environment and binding mechanism. Theoretical methods such as fluorescence resonance energy transfer (FRET) and molecular docking are also employed to predict the binding mechanism, binding modes, binding sites and the distance between the tryptophan residue in BSA and DPBF.

The study of atmospheric particulate matter has a high significance in realising the pollution status of any region. In this study, we have investigated the nature of PM2.5 aerosol samples over a semi-urban atmosphere located in the south-western part of India, using a low volume air sampler for 5 days (120 h). The analyses of the particles were carried out using Attenuated total reflectance - Fourier transform infrared (ATR-FTIR) spectrometer and Confocal micro Raman spectroscope. IR spectrum revealed the presence of both organic compounds and inorganic ions. Raman analysis showed the presence of large number of soot particulates. Sources such as biomass burning, cooking fuel (firewood) combustion, open waste burning, sea salt, soil dust, vehicular and industrial emissions contributed to aerosol loadings in the sampling site. NOAA’s Hysplit air trajectory model were used for the identification of distant sources that contributed to aerosol loading in the sampling location. This study revealed that the quality of air around the sampling site is good and that the local emissions from open waste burning and cooking fuel (firewood) combustion contributed to the enrichment of samples with carbonaceous aerosols.

There is a rise in concern across the globe over the contaminants of emerging concerns (CECs) such as pharmaceuticals, personal care products (PCPs), UV stabilizers, surfactants, endocrine disrupting compounds (EDCs), etc. In the present study, we have identified some compounds belonging to the classes of pharmaceuticals, PCPs, and EDCs in the water samples collected from the coastal area of Ernakulam district of Kerala (India) (sea and lake). The analysis was carried out using ultra-performance liquid chromatography coupled with quadrupole time-of-flight mass spectrometry (UPLC-Q-ToF–MS) after enrichment by solid-phase extraction. The nine CECs were identified in both positive and negative electrospray ionization mode (ESI). In both the matrices (sea and lake water), the highest concentration levels were noted for benzophenone (26.5–33.2 µg/l) and dibutyl phthalate (12.65–35.21 µg/l), whereas butyl and propyl parabens occurred at low concentration levels. The normality (Kolmogorov–Smirnov and Shapiro–Wilk) tests indicated that the concentration levels of contaminants among lake water samples were non-normally distributed. Whereas in seawater samples, the contaminant concentration levels were normally distributed. The analysis of homogeneity of variance and ANOVA test revealed no significant relationship between the contaminants detected from the lake and seawater samples. The risk assessment analysis showed that the organisms in the lake are at more risk compared to that of the sea. The results from the risk quotient (RQ) values obtained for each identified compound showed that the presence of dibutyl phthalate, butylparaben, and oxybenzone pose a medium risk to biological populations than other CECs.

The successful evolution of an effective drug depends on its pharmacokinetics, efficiency and safety and these in turn depend on the drug-target/drug-carrier protein binding. This work, deals with the interaction of a pyridine derivative, 2-hydroxy-5-(4-methoxyphenyl)-6-phenylpyridine 3-carbonitrile (HDN) with serum albumins at physiological conditions utilizing the steady state and time-resolved fluorescence techniques by probing the emission behavior of Trp in BSA and HSA. In-silico studies revealed a combined static and dynamic quenching mechanism for the interactions. The binding studies suggests a spontaneous binding between HDN and the albumins with a moderate binding affinity (Kb ∼ 10

Extensive use of surfactants in numerous fields resulted in their discharge into various environmental compartments including soil, sediment, and water. Alcohol ethoxysulfates (AES) together with alcohol ethoxylates (AE), alkyl sulfates (AS), and linear alkyl benzene sulfonates (LAS) find wide variety of applications in consumer products including both domestic and industrial applications. Consequently, all these surfactants pose several concerns to both aquatic and human health. In the context of environmental impacts, AES has almost equal importance as that of LAS though the literature on this topic is only emerging. This review provides a detailed overview on the various aspects of the anionic surfactant, AES, such as toxicity of AES, its fate in the ecosystem, technical advancements in the area of identification and quantification, its occurrence and distribution in different environmental compartments spanning across the world, and finally a remark of its potential removal strategy from the environment.

In this study, PSS doped CaCO3 microparticles were used as sacrificial templates for the fabrication of hollow polyelectrolyte microcapsules. The lysozyme loading studies of two systems - chitosan/...

The analysis of urinary nucleosides is becoming a very good tool in the diagnosis of diseases like AIDS and cancer and consequently the identification of modified nucleosides using mass spectrometry is an area of utmost importance. In this context, there is a high relevance in the understanding of the mechanism of collisionally induced dissociation (CID) of these heterocyclics. The present work characterizes and differentiates the cross-linked products formed by one electron oxidation of thymine (T). Three dimers A, B and C, were analyzed, out of which the dimer A is a C5–C5’ cross link of two T molecules containing a fused tetrahydrofuran ring, while B and C are N–C cross linked products. B and C showed very similar fragmentation pattern but that of A was different. The differentiation between these three were made by monitoring two characteristic peaks, the water loss peak ([M+H]+) and the protonated T fragment ([T + H]+). The probable mechanism of formation of these fragments and their CID mechanism in both positive and negative ionization modes are also explained. The neutral losses of NH3, H2O and NHCO were the prominent mechanism in the positive mode, while in the negative mode, only NHCO and CO losses were observed.

Layer by layer (LbL) assembly can be regarded as an emerging technology for the separation of organic micro-pollutants from water. Direct assembly of polyelectrolytes (PEs) under LbL mode on natural support material is rare. Here we report the integration of LbL to one of the most resourceful support materials that might have an enduring impact on water treatment in color industry. A low-cost adsorbent is developed from chitosan (CHI) and polyacrylic acid (PAA) through LbL deposition on coir fiber (CF) by alternate exposure to their aqueous solutions. Their layer dependent formation is characterized by spectroscopic and microscopic techniques. CHI/PAA multilayer coated coir fiber or simply, layered coir fiber (LCF) showed high loading of cationic and anionic dyes both at acidic and alkaline loading pH. The loading was between 70% and 99% at the acidic pH 3 which is attributed to the binding between LCF and dye molecules by electrostatic and hydrophobic forces. The performance of LCF in presence of NaCl, Na2SO4 and sodium dodecyl sulfate (SDS) in dye solution is discussed. Textile industrial waste water showed significant reduction in dye (81%) content along with COD (84%) and TDS.

Triphenylmethane (TPM) dyes are an important category of dyes with a variety of industrial applications and consequently, these are found in the aquatic environment at relatively higher concentrations. Here, we report the degradation of two important TPM dyes (para rosaniline (PRA) and ethyl violet (EV)) in an aqueous medium by ultrasound which is one among the Advanced Oxidation Processes (AOPs). The main objective of this work is to study the effect of various inorganic ions on the degradation and the product formation of TPM dyes from the sonochemical reactions. Using a typical concentration of 10 ppm dyes and an ultrasonic frequency of 350 kHz and power of 60 W, a complete degradation of EV and PRA was observed with a pseudo first order rate constant of 0.2339 min−1 and 0.1956 min−1, respectively. The product analyses using high-resolution mass spectrometry (LC-Q-TOF-MS) revealed the formation of hydroxylated, de-alkylated, and other collapsed conjugated structure destructed products. The evolution of these products in the presence of various inorganic ions (Cl−, SO42−, NO3−, and CO3−) showed that only carbonate ions had a significant impact on the product evolution. The carbonate ions facilitated the formation of conjugated structure destructed product for both the dyes. This is attributed to the reactivity of carbonate radical, which facilitated the formation of carbon-centered radicals. This carbon-centered radical further undergoes reaction to cause the destruction of conjugated structures. This is confirmed by the identification of the corresponding product peaks in the mass spectra. The scavenging effect of carbonate ions was also reflected in the product study where there is a reduction in the formation of most of the hydroxylated products. One of the major inorganic species in any wastewater is carbonate ions and therefore the present result is very relevant to the understanding of oxidation based treatment protocol.

Extensive use of surfactants in numerous fields resulted in their discharge into various environmental compartments including soil, sediment, and water. Alcohol ethoxysulfates (AES) together with alcohol ethoxylates (AE), alkyl sulfates (AS), and linear alkyl benzene sulfonates (LAS) find wide variety of applications in consumer products including both domestic and industrial applications. Consequently, all these surfactants pose several concerns to both aquatic and human health. In the context of environmental impacts, AES has almost equal importance as that of LAS though the literature on this topic is only emerging. This review provides a detailed overview on the various aspects of the anionic surfactant, AES, such as toxicity of AES, its fate in the ecosystem, technical advancements in the area of identification and quantification, its occurrence and distribution in different environmental compartments spanning across the world, and finally a remark of its potential removal strategy from the environment.

Graywater reuse is one of the important concepts in attaining water sustainability. A major challenge in this area is to realize various components present in graywater. The present study involves the identification of the chemical components of graywater collected from three different environments and to investigate the efficiency of removal of some of these chemical components using ultrafiltration membranes (polyelectrolyte multilayer (PEM) membranes). The chemical components were analyzed using liquid chromatography connected with quadrupole time-of-flight (UPLC-Q-ToF-MS). A number of micropollutants including surfactants and certain contaminants of emerging concern (CECs) were identified from these samples. Out of 16 compounds identified, 13 were surfactants and the remaining were caffeine, oxybenzone, and benzophenone. These surfactants are mostly the ingredients of various detergents. Low-pressure filtration studies of the collected samples were carried out utilizing chitosan/polyacrylic acid (CHI/PAA) multilayer membranes. A 5.5 bilayer membrane showed more than 95% rejection of the identified compounds in the selected samples and significant improvement in the water quality parameters. This demonstrates that the membrane used in this work is effective in the removal of various chemicals from graywater as well as enhancing the water quality.

Indoor dust is an important matrix that exposes humans to a broad spectrum of chemicals. The information on the occurrence of contaminants of emerging concern (CECs), their metabolites, and re-emerging contaminants in indoor dust is rather limited. As the indoor environment is exposed to various chemicals from personal care products, furniture, building materials, machineries and cooking/cleaning products, there is a high chance of the presence of hazardous contaminants in indoor dust. In the present study, dust samples were collected from four different micro indoor environments (photocopying centres, residential houses, classrooms, and ATM cabins) located in an urban environment located in India's southwestern part. The collected samples were subjected to ATR – FTIR and LC-Q-ToF-MS analyses. The ATR – FTIR analysis indicated the presence of aldehydes, anhydrides, carboxylic acids, esters, sulphonic acids, and asbestos – a re-emerging contaminant. A total of 19 compounds were identified from the LC-Q-ToF-MS analysis. These compounds belonged to various classes such as plasticisers, plasticiser metabolites, photoinitiators, personal care products, pharmaceutical intermediates, surfactants, and pesticides. To the best of our knowledge, this is the first report regarding the presence of CECs in indoor environments in Kerala and also the suspected occurrence of pesticides (metaldehyde and ethofumesate) in classroom dust in India. Another important highlight of this work is the demonstration of ATR-FTIR as a complementary technique for LC-Q-ToF-MS in the analysis of indoor pollution while dealing with totally unknown pollutants. These results further highlight the occurrence of probable chemically modified metabolites in the tropical climatic conditions in a microenvironment.

The mechanistic aspects of hydroxyl ( OH) and sulfate radical (SO4 −) induced oxidation of diphenylmethanol (DPM) in aqueous medium has been explored using a combined experimental and theoretical approach. OH initiates the generation of hydroxycyclohexadienyl-type radicals (i) upon reaction with DPM (λmax = 330 nm; k2 = (1.44 ± 0.08) × 1010dm3 mol−1 s−1). Time-dependent density functional theory (TDDFT) calculations revealed an ortho-hydroxylated adduct structure to radical i, which shows comparable absorbance characteristics (λmax = 322 nm). High resolution mass spectrometric (HRMS) studies reveal the existence of mono- and di-hydroxylated compounds of DPM and benzophenone as the main degradation products. Hydroxylated products werederived from the radical i by either a radical-radical disproportion or a bimolecular transformation felicitated by molecular oxygen. Benzophenone (III) is likely originated from the radical cation (iii), generated as a result of one electron oxidation of DPM by OH/SO4 −, by deprotonation followed by electron and proton release.

The intriguing resemblances of amyloid fibrils and spider silk in protein aggregation diseases have instigated the exploration of identical structural features if any in their oligomeric pathways. The serpin group protein, ovalbumin, on defolding in HgCl2 shares commonness to the micellar pathway of spidroins for their aggregation in response to a pH trigger. The structural feature changes from monomer to worm like fibril with a shift in the primary protein pH to slightly acidic pH (4.5), and then proceeds through a secondary nucleation pathway to ‘hillock’ and ‘hydra’ like protofibrils rich in β-sheet and random coil conformers upon exposure to mercury. The findings are backed by atomic force microscopy, confocal Raman spectroscopy and fluorescence measurements. Unlocking such structural features can favorably assist in the design of therapeutics.

A detailed investigation on the photocatalytic degradation and mineralization of lignocaine, a local anesthetic, under UV irradiation has been carried out in this study. The dose of TiO2 was optimized initially and was found as 250 mg L−1 for the degradation of 2 mg L−1 concentration of lignocaine. The scavenging experiment using isopropanol and methanol revealed that the degradation is mainly controlled by hydroxyl radical. A fast disappearance of the parent compound (within 1 h) and nearly 75% of mineralization (after 6hr) were observed using this method. The relatively low mineralization efficiency is due to the evolution of various transformation products during the degradation as identified by high-resolution mass spectrometry (LC-Q-TOF-MS). Ten well-separated product peaks were observed in the total ion chromatogram (TIC) for 30 min irradiated sample of lignocaine. Based on the formation of these products, a degradation mechanism is proposed involving mainly hydroxylation, N-de-ethylation, and hydrogen abstraction. As part of mineralization study, the evolution of various inorganic ions was analyzed and the ammonium ion is found as the major inorganic species. A detailed mechanism is proposed for the inorganic ion release as well.

Frustum shaped clay ceramic water filters are being manufactured by the potters of the Thar Desert in India for household use. The clay composite consists of a homogeneous mixture of equal volume of clay and sawdust. A low-cost manual press, to form the clay composite into frustum shape, is developed by the present authors. This article elaborates critical investigation of the specific traditional clay-firing technique used, to achieve the required functionality and material property of the filters. Household based manufacturing of these filters is found to be markedly different from factory based production by firing process. The functional features of the clay ceramic filter, such as microbial filtration rate, flow rate, and compressive strength, are evaluated and presented. An E. coli bacteria removal efficiency of more than 99% is achieved using these clay ceramic water filters. Optimal filtration rates are achieved between ambient temperatures ranging from 30oC - 40oC.

The sonochemical transformation of para-aminosalicylic acid (PAS), a widely used antibiotic and an identified Emerging Pollutant (EP) under the class of Pharmaceuticals and Personal Care Products (PPCPs), have been investigated in aqueous medium. Ultrasound having frequency of 350 kHz and power of 80 W was utilized for the degradation of PAS. A complete degradation (100%) of PAS after 60 min and about 83% of COD removal after 120 min of sonication, were obtained. Fourteen intermediate products were identified using LC–Q-TOF–MS. On a comparison with UV/H2O2 method, it is understood that four products out of fourteen were nitro derivatives which are formed only in the sonolysis, and the rest are from hydroxyl radicals. The involvement of nitrite which is formed from the sonolysis of solution containing PAS, in the formation of the other four nitro products has been established from the control studies. Nitrite ion partially scavenge hydroxyl radical in the course of the reaction to form nitrite radical which is the reactive species for the production of nitro compounds. It is, therefore, proposed that in addition to hydroxyl radical, contribution of in-situ generated nitrite also plays an important role in the sonochemical transformation of PAS.

The present study describes the monitoring of some of the major classes of surfactants in water. The separation, identification, and the quantitative estimation of the compounds were achieved using LC-Q-ToF-MS. The analyses revealed the presence of variety of surfactants including linear alkylbenzene sulfonate (LAS), alcohol ethoxysulfates (AES), and alcohol ethoxylates (AE). Further, emphasis was given to AES as they are one of the most produced and consumed surfactants in the world. And as far as India is concerned, the present study is one of the most significant attempt regarding the identification and quantification of AES. The data obtained during the analysis revealed that the average concentration of AES C12Ex varied from 0.7 to 13.6 μg L−1 while that of C14Ex ranged between 1.3 and 10.4 μg L−1. The risk assessment revealed that higher chain AES are capable of posing medium level risk to the aquatic compartment. In addition, the study also included the physicochemical analysis of water from the selected area. Water was found to be acidic in nature and the salinity, TDS, and EC values were found to be high during the pre-monsoon season. The order of the levels of anionic constituents was of Cl−>SO4 2−SO4 2−>F−>NO3 2− ≅ PO4 2− while that of cations were Na+ > Mg2+ > K+ > Ca2+. Results of correlation analysis showed that statistically negative correlation exists between AES homologs and pH while slight positive correlations were found between AES and other parameters including TDS and EC. The suitability of this water for domestic and agricultural purposes has been examined on the ground of basic quality indices such as the water quality index (WQI) and sodium adsorption ratio (SAR). The WQI measurements also revealed that the water quality of the region falls under the “very poor” category especially during the pre-monsoon season. The study could explore the cumulative share of these canals in the quality impairment of the receiving Vembanad Lake.

Microfiltration (MF) membranes with chitosan/polystyrenesulfonate (CHI/PSS) functional layer coated surface can act as a barrier against emerging contaminants (ECs) in water under low pressure. One (one bilayer) or two functional layers are enough for the removal of lidocaine (LD, 100%) and ibuprofen (IBU, >75%). The effect of various ions, surfactant and humic acid is studied along with the influence of feed pH. Phosphate interferes negatively with the removal efficiency of membrane for IBU and sulfamethoxazole (SMZ). The reusability of the membranes are illustrated by the desorption studies of LD. The extended life of membrane and hence the antifouling nature of the selected ECs indicate its potential in small scale filtration units. Effect of ionic strength in feed and in deposition medium on the rejection percentage is presented. This study shows that various mechanisms depending on the properties of ECs are responsible for the rejection of ECs.

Implications of sulfidized Fe 0 (nFe/FeS) for the abatement of pollutants of various categories are widely established. In this study, degradation of one of the major organic pollutants, benzoic acid (BA), has been performed using persulfate activated with nFe/FeS. Complete degradation of BA and its transformed product, hydroxybenzoic acid, was observed within 6 min. When the degradation was performed at alkaline pH, the degradation decreased to 8% in the case of Fe 0 , but nFe/FeS still showed 100% degradation after 60 min. Iron dissolution and persulfate decomposition in the presence of scavengers showed that both sulfate and hydroxyl radicals were involved in the Fe 0 -persulfate system and that the hydroxyl radicals were the major species in the nFe/FeS-persulfate system. The major degradation pathway of benzoic acid was hydroxylation followed by complete mineralization, as supported by the practical removal of total organic carbons (more than 75% within 15 min). The observed results are promising in using persulfate activated by nFe/FeS for the remediation of various micro-pollutants from a multitude of water sources.

Off-white water pots have had sustained traditional acceptance for a long period of time in Jodhpur compared to red colored water pots imported from the neighboring Gujarat state. Both types of pots hold 20 liters of potable water. The fluorescence spectroscopy reveals dominance of silica, alumina and iron oxide in red pots from Gujarat whereas off-white pots from Rajasthan also have a slight excess of CaO and MgO. Fourier transform infrared spectroscopy reveals a firing temperature of 800 °C for off-white pots, which is comparatively less than that for red pots. A lower amount of Fe2O3 and higher MgO in off-white compared to red water pots is responsible for the color differentiation. Off-white pots show a better degree of cooling compared to red pots. Better resistance to load was observed in off-white pots compared to red pots. This study may imply influence of hidden techno-functional aspects towards sustainability of off-white pots in Jodhpur, Rajasthan.

A low saline backwater canal, mainly utilized for domestic and agricultural purposes, has been analyzed for the possible presence of organic micropollutants (OMP) and their potential removal was explored by multilayered microfiltration membranes. The qualitative as well as quantitative analysis were carried out for a span of one year using the technique of liquid chromatography connected with high resolution mass spectrometry (LC-Q-TOF-MS). The identification of the formally unknown compounds was initially done using non-target analysis based on the mass accuracy, isotopic pattern and MS/MS spectral interpretation. Results of the non target screening revealed the presence of 11 OMPs. Five of these OMPs were confirmed using standards; these include chlorophene (CHP), oxybenzone (OXY), N, N-diethyl-meta-toluamide (DEET), N, N-diethyl-benzamide (DEB) and dibutyl phthalate (DBP). Among the confirmed OMPs, the highest concentration was observed for DBP (244.61 ng l−1). The most frequently observed OMP in the study area was DBP while the least was DEB which is an insect repellent as well as a degradation product of DEET. The ecological risk associated with the target compounds has also been analyzed by calculating the risk quotient (RQ) and the results revealed that at the detected levels, these compounds are capable of causing low to medium risk. Low pressure (

BACKGROUND As amino acids provide a green feedstock for the synthesis of chemicals, their isolation through low energy route sounds encouraging. RESULTS The changes in the permeation characteristics of microfiltration (MF) membranes with the deposition of a few bilayers of chitosan (CHI) and polystyrene sulfonate (PSS) for the low pressure filtration (∼0.69 bar) of selected amino acids glycine, histidine, lysine and aspartic acid is reported here. Glycine, with minimal electrostatic interaction with the multilayer film, is almost completely transmitted. Among the basic amino acids, lysine was isolated to a larger extent at both pI (pH 9.5, 7 bilayer, 67.8%) and below pI (pH 5, 7 bilayer, 96.4%). Aspartic acid was also isolated at both feed pHs (pH 5, 93.6%). Donnan effects operate in a different manner in both cases. At pH 5, lysine is adsorbed to the membrane as counter ions, whereas aspartic acid is excluded as co-ion from the film. The morphological features of membranes are illustrated through histogram, skewness, and Minkowski measures using AFM. CONCLUSIONS The present study brings forward the possibility of cutting down the filtration pressure to a lower value for the isolation of small molecules like amino acids by water based coating of a few bilayers on MF membranes. © 2016 Society of Chemical Industry

Mechanistic aspects of diphenhydramine (DPH) oxidation induced by hydroxyl (•OH) and sulfate (SO4•−) radicals have been explored in detail by pulse radiolysis technique and high resolution mass spectrometry (HRMS). The transient absorption spectrum along with HRMS analysis undoubtedly established the non-position selective hydroxylation of DPH by •OH (a; k2 = (1.08 ± 0.06) × 1010 dm3 mol−1 s−1; λmax: 335 nm) led to various transformation products (i - vii) including isomeric mono (Ia-d), di (IIa-c) and tri (VIIa-e) hydroxylated analogues. On the other hand, SO4•− (specific one electron oxidant) ultimately generates another hydroxylated adduct radical ‘c’ λmax: 330 nm, k2=(5.70 ± 0.03) × 109dm3 mol−1 s−1) which is formed as a result of preferential hydroxylation of initially formed radical cation ‘b’ at ipso position. The mechanism leading to the formation of various transformation products induced by •OH and SO4•− are thoroughly discussed. The mechanistic findings obtained from our studies (especially in the case of less investigated oxidant like SO4•−) are capable to enrich the fundamental understanding on environmentally relevant reactions initiated by •OH and SO4•−.

Ultrasound is known to degrade organic compounds by pyrolysis and by the reaction of free radicals. In this work, sonolytic degradation of an identified water pollutant, coomassie brilliant blue (CBB), has been carried out in pure water as well as in river water. In the case of pure water, 90 % degradation was obtained after 30 min of sonication (350 kHz frequency, 60 W power), whereas in river water, the same efficiency was achieved only after 90 min. The degradation was also performed in the presence of varying concentration of (10–100 mg L−1) inorganic ions such as chloride, sulfate, nitrate, bicarbonate, and carbonate ions which were detected in the river water sample. Higher concentration of chloride enhanced the degradation due to the salting out mechanism. The enhancement of degradation in the presence of nitrate is mainly due to the change in the surface potential at the interface of the cavitating bubble. Bicarbonate ion and carbonate ion enhanced the degradation due to the involvement of carbonate radicals. A possible degradation mechanism is proposed based on the product profile determined by LC-Q-ToF-MS. The low efficiency of degradation in river water compared to that in pure water is likely due to the increased rate of bubble dissolution or escape of bubbles (degassing effect), and the scavenging of •OH by the organic content (high chemical oxygen demand (COD)).

Degradation of benzenesulfonic acid (BSA), the simplest aromatic sulfonic acid with extreme industrial importantance, by sonochemically generated hydroxyl radical ( OH) have been thoroughly investigated. A reasonable reduction (∼50%) in the total organic carbon (TOC) was achieved only after prolonged irradiation (∼275 min, 350 kHz) of ultrasound, although a short irradiation of less than an hour is enough to degrade significant amount of BSA. The degradation efficiency of ultrasound has been reduced in lower and extremely higher frequencies, and upon increasing the pH. An irregular, but continuous, release of sulfate ions was also observed. Further, the release of protons upon the oxidation of BSA consistently reduces the experimental pH to nearly 2. High resolution mass spectrometric (HRMS) analyses reveals the formation of a number of aromatic intermediates, including three mono (Ia-c) and two di (IIa&b) hydroxylated BSA derivatives as the key products in the initial stages of the reaction. Pulse radiolysis studies revealed the generation of hydroxycyclohexadienyl–type radicals, characterized by absorption bands at 320 nm (k2 = (7.16 ± 0.04) × 109 M−1 s−1) and 380 nm, as the immediate intermediates of the reaction. The mechanism(s) leading to the degradation of BSA under sonolytic irradiation conditions along with the effect of various factors, such as the ultrasound frequency and reaction pH, have been explained in detail. The valuable mechanistic aspects obtained from our pulse radiolysis and HRMS studies are essential for the proper implementation of sonochemical techniques into real water purification process and, thus, receives extreme environmental relevance.

Zinc oxide nanocomposites with Li and Ag doping were synthesized and were characterized by scanning electron microscope (SEM), X-ray diffraction (XRD), diffused reflectance spectroscopy (DRS), Raman spectroscopy, X-ray photoelectron spectroscopy (XPS) and time of flight secondary ion mass spectroscopy (ToF-SIMS). A peak shift was observed in XRD diffraction patterns, which was due to the lattice strain which was created by the doping of Li and Ag. Four phonon modes in Raman spectra corresponds to wurtzite structure with C6v space group. In ToF-SIMS, the presence of Li has been confirmed with its isotopes at m/z 6.01 and 7.01 respectively. For Candiasis albicans, the final microbial count after 10 h were 2.1 × 104, 1.8 × 103, 1.1 × 103, 1.6 × 102, 1.0 × 102 and 3.0 × 101 colony forming unit (cfu) in case of ZnO, lithium doped ZnO and Ag (0.5 mM, 1 mM, 3 mM, 5 mM) incorporation in Li doped ZnO matrices respectively, while the microbial count were 2.4 × 105, 1.6 × 104, 4.8 × 102, 3.2 × 102, 1.1 × 102 and 1.5 × 102 cfu in the case of the ZnO, lithium doped ZnO, Ag (0.5 mM, 1 mM, 3 mM, 5 mM) incorporation in Li doped ZnO matrices, respectively.