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A novel adsorbent, 4-formylphenyl boronic acid grafted amino MCM-41 (b-MCM) was synthesized and characterized followed by its application for the removal of copper(II) ions from water. Adsorption data was subjected to isotherm and kinetic studies. Maximum adsorption capacity calculated from Langmuir isotherm was found to be 215.40 mg/g. Adsorption process was optimized using response surface methodology (RSM) for achieving the maximum efficiency at different pH, temperature and concentration. b-MCM was also successfully applied as packing material in column studies and found to remove 100% of Cu(II) ions which proves its candidature as an excellent alternative for wastewater treatment.

Mitigation of Pb(II) ions from water using economic method is an important research area to combat the pollution due to lead ions Pb(II) in water as it have severe toxic effects in human beings. In present work, Pristine Pavo Cristatus feather powder (PCFP) has been employed for removal of Pb(II) ions and the process of adsorption was optimized through four level Box Behnken design (BBD) of response surface methodology (RSM) over a broad range of pH (3.0–9.0), initial lead ion concentration (20–100 mg/L), contact time (20–180 min) and temperature (297 K to 333 K). Different isotherms were applied to confirm the type of adsorption. Langmuir maximum removal efficiency was 121.95 mg/g for lead ions adsorption onto PCPF at optimal values of pH 6; adsorbent dose 20 mg/L; temperature 303 K and contact time 120 minutes obtained from batch studies. Pseudo-second-order reaction model showed good applicability for kinetic studies. Thermodynamic parameters were also evaluated to check feasibility and nature of adsorption. The optimal parameters obtained for maximum Pb(II) ions adsorption were at pH = 6.31, initial Pb(II) ion = 43.79 mg/L, contact time = 119.51 minutes and temperature = 59.67 oC. The experimental and predicted values were found to be in good agreement with each other.

Cadmium is one of the toxic heavy metal that is discharged into the surroundings by various routes such as sedimentary rocks, weathering and erosion of rock, earth’s crust, marine phosphate and phosphorites, forest fires etc. However battery manufacturing industry, plated containers, mining, auto exhaust, smelting of nonferrous metals, cigarettes ore dressing, and galvanized pipes are the main anthropogenic sources of cadmium heavy metal in environment. Ingestion of cadmium in human body increases the risk of many diseases. Many techniques have been applied for the removal of cadmium heavy metal ions from water. The aim of the current work is to propose economical material for effective cadmium ion removal from aqueous phase. A Pavo cristatus feather which is locally available and low-cost is used as an adsorbent for the removal of cadmium ions from water. The adsorption ability of Pavo cristatus feather has been investigated as a function of concentration of cadmium, pH of solution, adsorbate concentration, contact time and temperature. Maximum adsorption of cadmium on Pavo cristatus feather was observed at 5 pH of the solution. Adsorption of cadmium on Pavo cristatus feather was initially found to increase with increase in concentration of cadmium, time of contact and adsorbate concentration. The Langmuir, Freundlich and Temkin adsorption isotherm models were applied to analyse the experimental data. The experimental data was well fitted to Langmuir isotherm model. However, the maximum Langmuir adsorption capacity for cadmium on Pavo cristatus feather at pH 5 was 64.52 mg/g. The kinetics study was examined using the pseudo first order and pseudo second order kinetic models and was best described by the pseudo second order model. Thermodynamic parameters such as the change of Gibbs free energy, entropy and enthalpy of adsorption were also calculated. The study showed that Pavo cristatus feather can be used as a low cost and efficient adsorbent for removal of heavy metal ions from industrial wastewater/water. This material may also be utilized for removal of other toxic heavy mental ions from water.

In this paper we study the effect of Mass and Heat transfer under the existence of transverse magnetic field for an oscillating two dimensional Micro-polar fluid flow through a moving infinite permeable plate in a porous medium. Investigate the Solutions for angular momentum, governing momentum, energy and concentration equations. Study the effect of chemical reaction, permeability parameters, velocity profiles, micro rotation profiles, wall stress coefficient and skin friction coefficient by using graph.

Management and control of pandemic and endemic diseases is one of most important issue in order to deal with unpredicted health emergencies and fatalities all over the world. Covid-19, a new version of corona virus, originated from the Wuhan province of mainland China somewhere in December 2019 and has spread across the globe. Pandemic Covid-19 has affected the life of humans in almost every region of the world. Different strategies were planned by the regulatory bodies of different countries in order to slow down the transmission rate. The transmission rate was not uniform and varied from region to region. This chapter highlights the transmission dynamics of the virus and monitors the transmission among top five countries with highest number of infected persons as on May 31, 2020 and predicts the situation further. Linear regression techniques have been used for the purpose of analysis and prediction. The prediction model obtained is based on the trend of the data with highest R2value and minimum residual. The model helps the authorities to make necessary arrangements during the emergency.

A spectrophotometric method based on diazotization of aniline with triclosan has been developed for the determination of triclosan in water samples. The diazotization process involves two steps: (1) reaction of aniline with sodium nitrite in an acidic medium to form diazonium ion and (2) reaction of diazonium ion with triclosan to form a yellowish-orange azo compound in an alkaline medium. The resulting yellowish-orange product has a maximum absorption at 352 nm which allows the determination of triclosan in aqueous solution in the linear concentration range of 0.1–3.0 μM with R2 = 0.998. The concentration of hydrochloric acid, sodium nitrite, and aniline was optimized for diazotization reaction to achieve good spectrophotometric determination of triclosan. The optimization of experimental conditions for spectrophotometric determination of triclosan in terms of concentration of sodium nitrite, hydrogen chloride and aniline was also carried out by using Box–Behnken design of response surface methodology and results obtained were in agreement with the experimentally optimized values. The proposed method was then successfully applied for analyses of triclosan content in water samples.

Punica granatum carpellary membrane (PGCM) has been chemically modified with 2,4 dinitrophenylhydrazine by one step reaction process. Pristine PGCM and modified Punica granatum carpellary membrane (MPGCM) have been employed as adsorbents for removal of cadmium (II) ions from aqueous solution. Modification on the surface of PGCM was characterized by Fourier transform infrared, scanning electron microscope, energy dispersive X-ray spectroscopy and X-ray diffraction techniques. Removal of Cd (II) ions was carried out at various optimized conditions i.e. adsorbent dose (20 mg/l), pH (7), contact time (2 h), and temperature (303 K). The Langmuir isotherm model was the best fit with a high value of regression coefficient (R 2 = 0.991–0.999) compared with the Freundlich and Temkin models. Langmuir maximum adsorption capacity for cadmium was found to be 111.11 mg/g for PGCM and 142.85 mg/g for MPGCM. Kinetics of adsorption of cadmium onto MPGCM was best described by pseudo-second-order kinetics model compared with pseudo-first-order. The negative value of free energy change showed that adsorption was highly spontaneous and favorable. Also the positive value of entropy and enthalpy showed that the process of adsorption was associated with increased randomness and endothermic in nature. Mechanism of removal of cadmium ions from water by MPGCM has also been explicated.

Silver nanoparticles (AgNPs) find applications in many consumer products due to their unique properties. It is imperative to contend with the safety issues in respect of AgNPs during manufacturing, usage, and after disposal, as manufacturers as well as consumers are likely to be exposed to these particles. This review seeks to scrutinize the current challenges in obtaining input parameters for conducting risk assessment of exposure to Ag NPs and specifically focuses on exposures of humans to Ag NPs through oral ingestion of Ag NPs via edible parts of plants, water, soil ingestion, and fish, and through dermal uptake exposure pathways. The present status of toxicological studies of silver nanoparticles and challenges in assessing risks of exposure to silver nanoparticles has been discussed in detail. The limited and contradictory existing data imply that prudence must be exercised when potential exposures to silver nanoparticle emerge from different routes.

C16-6-16 incorporated mesoporous MCM-41 was investigated as an effective adsorbent for the adsorption of cadmium ions from the aqueous medium. Adsorption process was affected by different physiochemical factors such as pH, initial concentration, temperature and contact time. Optimization of experimental data was done to find out best optimal conditions using response surface methodology. Twenty nine trials were runs according to Box–Behnken design. Quadratic model was found to be best fit with maximum R2 value 0.9954 and gives the suitable relationship between the variables and response. The optimal parameters were obtained for adsorption of cadmium ions on to C16-6-16 incorporated mesoporous MCM 41. The results showed that the adsorption conditions have considerable effects on the removal of cadmium ions.

Punica granatum carpellary membrane powder (PGCM) and its surface modified form (MPGCM) with 2,4-dinitrophenylhydrazine (2,4-DNP) were used as adsorbents for removal of bivalent lead ions from aqueous phase system. Batch mode experiments using various parameters were carried out to assess the adsorption isotherms and dynamics of the process. Langmuir isotherm was well-fitted model for experimental data. Langmuir adsorption capacity using PGCM and MPGCM at pH of 7 was found to be 169.49 and 196.07 mg/g, respectively. Rate constant and thermodynamic parameters were calculated to evaluate the kinetic model and temperature dependence nature of adsorption. Box-Behnken design was applied to optimize the adsorption process of bivalent lead ions for PGCM and MPGCM using pH (3.0-9.0), initial bivalent lead ions concentration (20-100 mg/L), contact time (20-180 min), and temperature (20-60°C) parameters. The optimum conditions for maximum removal of bivalent lead ions on PGCM were found to be at pH of 6.99, initial bivalent lead ions concentration of 98.95, contact time of 176.05, and temperature of 21.20°C and on MPGCM at pH of 6.51, initial bivalent lead ions concentration of 99.99, contact time of 177.89, and temperature of 20.02°C, respectively. PRACTITIONER POINTS: Adsorption of bivalent lead from water using Punica granatum carpellary membrane powder and its modified form MPGCM is discussed. Batch mode experiments using various parameters were carried out to assess the adsorption isotherms and dynamics of the process. Langmuir adsorption capacity using PGCM and MPGCM at pH of 7 was found to be 169.49 and 196.07 mg/g, respectively. Box-Behnken design was applied to optimize the adsorption process of bivalent lead ions.

Adsorption of lead ions by mesoporous material incorporating Gemini surfactant C16-6-16 (G-MCM-41) was investigated using response surface methodology. The effect of pH, initial metal concentration and contact time was studied using Box-Behnken design (BBD). The optimal parameters for maximum adsorption capacity (81.92 mg/g) were obtained at pH 5.85, initial lead ion concentration 99.02 mg/L, and contact time 118.49 min. The effect of different variables and their interactions were assessed by analysis of variance (ANOVA). The surface and contour response plot shows the interaction of different variables and response. The experimental data fits best in the quadratic model with maximum predicted R2 value of 0.9013 and Prob > F is

Medical diagnosis with the help of computational techniques is a very useful tool for doctors for the purpose of better diagnosis. In this chapter, an attempt has been made to reduce the number of tests required for diagnosis using generalized fuzzy sets for initial decision making as per the characteristics of ingested water in normal routine. The quality of water in terms of type and concentration of contaminants varies from region to region. The analogy between concentration of different contaminants in drinking water and risk analysis based on intuitionistic fuzzy sets (IFSs) have been investigated. Hypothetical data was processed in view of the finite set of heavy metals, diseases, and places to investigate the effect of selected heavy metal on the human health. The findings will not only help in diagnosis but also offer cost-cutting and ecofriendly strategy by avoiding unnecessary clinical laboratory examinations.

Amino-functionalized mesoporous MCM-41 (NH 2 -MCM-41) has been synthesized and explored as sorbent for removal of trivalent chromium, from aqueous media. The chemical and morphological structures of NH 2 -MCM-41 were investigated by scanning electron microscopy, energy-dispersive x-ray, and x-ray diffraction techniques. The best performance of NH 2 -MCM-41 as sorbent for removal of trivalent chromium was observed at optimized conditions: pH 3, adsorbent dose (1 g/L), contact time (2 hrs) and temperature (40 °C). Langmuir isotherm model was best fitted to the experimental data with high value of regression coefficient compared to Freundlich and Temkin models indicating monolayer adsorption of the chromium ions on the surface of NH 2 -MCM-41 with the maximum Langmuir adsorption capacity of 83.33 mg/g. The adsorption mechanism can be explained by the combined effects of strong chemical interaction of chromium (III) ions with the surface amino group and some un-reacted silicate groups of NH 2 -MCM-41. Adsorption kinetics was best described by pseudo-second-order kinetics model as compared to pseudo-first-order and followed by both diffusion as well as intra-particle pore diffusion mechanism. Thermodynamic analysis revealed that the adsorption was highly favorable, spontaneous and endothermic in nature which allows application of amino-functionalized MCM-41 as a promising adsorbent for the treatment of industrial effluents and other environmental samples.

Fullerenes may be introduced to water during the life cycle/processing/disposal of products leading to the exposure of fullerene to human beings. The review of human health risk assessment (HHRA) studies indicated that very few studies have focused on exposures of specific carbon-based materials from water medium, indicating a knowledge gap. To understand difficulty in conducting HHRA, this study focused on identifying knowledge gaps in occurrence and toxicity data for assessing exposure risks of fullerenes in water using published studies. Knowledge gaps in four important areas were observed: (i) levels of fullerenes in water and fish tissues, (ii) oral exposure of fullerene, (iii) dermal exposure of fullerene, and (iv) conditions used in toxicity studies. This study proposed suggestions for addressing these knowledge gaps which could aid in assessing health risks of fullerene exposures from water route.

Nanomaterials have wide applications as sorbents for water purification as they have high selectivity as well as capacity for organic/inorganic pollutants and contaminants in aqueous solutions. Non-essential toxic heavy metals present in water have become a major cause of many diseases, ageing, and genetic problems. Carbon-based nanomaterials have generated great interest in their use as sorbent materials for removal of heavy metals from water/wastewater as they are stable, have limited reactivity, wide surface area, and are strong antioxidants. This study explored the possibility of ranking different carbon-based nanomaterials for efficient removal of lead ions from water which are routinely detected in water samples. Lead may be introduced in water because of its intensive use in many products. The adsorbents based on graphenes and carbon nanotubes have been analyzed on the basis of adsorption capacity, reusability, toxicity/biocompatibility, and cost. The effects of surface area of sorbent, pH of water, thermodynamics/kinetic studies have also been analyzed to evaluate the efficiency of sorbents. The information can be utilized to select the appropriate, most efficient and safe sorbents for removal of lead ions from water.

A green environment and a healthy life are dream projects of today's science and technology to save the world. Heavy metal ions in water affect both environment and human health. Cadmium has been identified as one of the heavy metals that causes acute or chronic toxic effects if ingested. Increasing use of cadmium in different technological fields has raised concern about its presence and removal from water/wastewater. Researchers have made many systematic efforts to remove heavy metals from water to reduce their impact on human beings and the environment. Adsorption is one of the best methods to remove heavy metals from water among the different proposed methods. This study explores carbon-based nanosorbents which have been proved as effective adsorbents for removal of cadmium ions from water. The adsorption efficiency of carbon-based nanosorbents is the main criterion to rank and select them for removal of cadmium ions from water. Toxicity, reusability and environmentally friendly characteristics of sorbents are also taken considered while ranking the suitable carbon-based nanosorbents for removal of cadmium ions from water.

Environmental water samples contain wide range of contaminants including heavy metal ions that are required only in trace amount. Excessive level of metal ions in water may be detrimental to health and environment. Heavy metal poisoning has been a serious concern all over the globe. Heavy metals are well known to be non-biodegradable and tend to bio-accumulate at various concentrations. A number of methods have been proposed to remove heavy metal ions from water and among them adsorption is one of the best methods. Cadmium has been identified as one of the toxic heavy metals that enters the water through disposal of waste from industries. The increasing technological use of cadmium has raised the concern for its removal from water/wastewater. This review article provides an overview of use of nano-metal oxides as adsorbents for removal of cadmium from water/wastewater. This study involves the identification of environmentally friendly, low-cost and efficient nano-metal oxide sorbents for water/wastewater purification. A detailed comparison of reported nano-metal oxide sorbents has been done in order to rank them and to predict the knowledge gaps in this area.

This article deals with the cloud point studies of ethoxylated sorbitan ester, Tween in the presence of glycols, and salts. Cloud point temperature of Tween 20 (5 mol dm−3) and Tween 80 (1 mol dm−3) has been determined in the presence of various salts in addition to glycols. The glycols chosen for these studies were triethylene glycol (TEG), and ethylene glycol mono butylether (EGMBE). At concentration below 0.02 M these salts have no significant effect on cloud point temperature in all cases. The cloud point temperature of Tween+TEG and Tween+EGMBE found to decrease in the presence of sodium chloride (NaCl) and potassium chloride (KCl). The cloud point temperature of Tween 20 + TEG and Tween 20 + EGMBE found to increase in the presence of urea and nicotinamide. The change in cloud point was found to be more in case of nicotinamide as compare to urea. The influence of an additive on the cloud point depends on how it affects the intermicellar interactions. An effort has been made to understand the interact...

Small-angle neutron scattering (SANS) and turbidity measurements have been carried out on the nonionic surfactants Tween 20 and Tween 80, in the presence of diethyleneglycol (DEG), triethyleneglycol (TEG), ethylene glycol monoethyl ether (EGMEE), and ethyleneglycol mono butyl ether (EGMBE). SANS measurements show that the shapes of the Tween 20 and Tween 80 micelles are oblate ellipsoidal, which do not change predominantly in the presence of DEG and TEG. However, the presence of EGMBE and EGMEE reduces the aggregation number of Tween. This has been attributed to the solubilization of EGMBE and EGMEE in the Tween micelles, providing them with additional hydrophobicity.

The cyclic voltammetric measurements were carried out for Tween 20 and Tween 80 in the presence of various glycol oligomers consisting of monomeric glycol to polymeric glycol (triblock polymers) additives. Lower glycol oligomers destabilize the Tween micelles by solubilizing themselves at micelle–solution interface. Triblock polymers stabilize the Tween micelles by forming mixed micelles with enhanced hydrophobicity. The nature of Tween–glycol aggregates is explained on the basis of obstruction effects encountered by electroactive probe molecules.

Cloud point (CP) measurements of Tween 20 and Tween 80 were carried out in the presence of various glycol oligomers and triblock polymers (TBP). The cloud points of both Tween 20 and 80 decrease in the presence of both types of additives. Among the glycol oligomeric additives, ethylene glycol monobutyl ether was found to reduce the CP maximum. An increase in the repeating units of polymeric glycol additives leads to a decrease in CP. Reduction in the CP in the presence of TBP depends upon the increase in hydrophobic/hydrophilic ratio among the polypropylene to polyethylene units.

Nefopam hydrochloride is a non-narcotic analgesic used parenterally and orally as a racemic mixture for the relief of postoperative pain. However, no information is presently available on the oral kinetics of (+) and (-) nefopam in humans. Also, nefopam is metabolized by N-demethylation but it is not known whether the desmethylnefopam enantiomers (DES1 and DES2) are present in plasma following intravenous (I.V.) or oral administration of parent drug. To address these issues, 24 healthy white male subjects received two treatments using a double-blind, placebo-controlled crossover design: oral administration of 20 mg nefopam hydrochloride solution or a placebo solution on a sugar cube, simultaneously with a continuous infusion of 20 mg nefopam hydrochloride or placebo infusion. A chiral assay using LC-MS was developed for the simultaneous determination of both enantiomers of the parent drug and its metabolite in plasma and urine. Following I.V. administration, the kinetics of (+) and (-) nefopam could be fitted to a bi-exponential equation but exhibited no stereoselectivity. Both enantiomers had large clearances (53.7 and 57.5 L/hr) and volumes of distribution (390 and 381 L) and half-lives around 5 hours. Following oral administration, (+) and (-) nefopam were rapidly absorbed with bioavailabilities of 44% and 42%, respectively, probably due to a first-pass effect. After I.V. administration, the enantiomers of desmethylnefopam exhibited lower concentrations and longer half-lives (20.0 h for DES1 and 25.3 h for DES2) relative to nefopam enantiomers. Following oral administration, desmethylnefopam enantiomers' plasma concentrations peaked earlier and higher than after I.V. administration (P < 0.05). Following I.V. and oral administration, desmethylnefopam enantiomers showed stereoselectivity in AUC and Cmax values. Urinary excretion of parent and metabolite enantiomers was less than 5% of dose. This study shows that desmethylnefopam enantiomers can contribute to the analgesic effect of racemic nefopam only when it is administered orally.

Carbon-based nanoparticles have attracted much attention because of their unique properties like specific strength, lightness, electrical properties and also show several promising potential applications in biology and pharmacology. However, their growing use and mass production have raised several questions about their probable unfavourable effects on human health. For example, use of carbon nanotubes (CNTs) and fullerenes are there in maximum number of consumer products containing carbon-based nanomaterials and have been reportedly found in environmental samples (Farre et al. 2010).

Small angle neutron scattering (SANS) technique has been used to study the micellar behavior of nonionic surfactants, Tween 20 and Tween 80 with additives like polyethylene glycols (PEG with molecular mass 400, 6000, and 15,000) and triblock polymers (TBPs) of varying composition. Surfactant-additive interactions have been explained on the basis of parameters like aggregation number (Nagg), core radius (Rc), hard sphere radius (Rhs), volume fraction (ϕ) and axial ratio (b/a). The SANS analysis indicate the reduction in values of Nagg of Tween on addition of PEG additive. Shape of Tweens (3 wt %) micelles in the presence of PEG (10 wt %) is found to oblate ellipsoidal. Similarly, the shape of Tween (3 wt %) micelles is oblate ellipsoidal at low concentration of TBPs (1 wt %); however, they become spherical as the concentration of TBP increases to 10 wt %. The shape of micelles of pure TBPs also comes out to be spherical. Results reflects that at low concentration of TBP shape is controlled by surfactant (Tween 20 and Tween 80) while at high concentration of TBP shape of mixed micelle is controlled by TBP. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010

A 5-year-old male child presented with progressively increasing asymmetrical overgrowth of limbs, hyperpigmentation on the right half of the body, and mental retardation since 9 months of age.