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The inclusion complex of diphenylamine (DPA) in 2-hydroxypropyl β-cyclodextrin (HP-β-CD) was synthesized by a co-precipitation method. The structure and molecular properties of the newly synthesized inclusion complex (DPA: HP-β-CD) were investigated along with a β-cyclodextrin (β-CD) inclusion complex (DPA: β-CD) using various analytical and theoretical methods. Phase solubility, absorption, fluorescence, Fourier transform-Infrared spectroscopy (FTIR), powder X-ray diffraction (PXRD) and scanning electron microscope (SEM) techniques were used to investigate the structural properties of the DPA before and after being encapsulated by the CDs (β-CD and HP-β-CD). Furthermore, the antioxidant and antibacterial activities were evaluated for DPA and the inclusion complexes (DPA: β-CD and DPA: HP-β-CD). The structure of the inclusion complexes was proposed based on the experimental results and their structural optimization was done using Becke's three parameter density functional theory using Lee-Yang-Parr's 3-21 G method in the gas phase. Then the various theoretical molecular properties, such as frontier molecular orbitals (FMO), molecular electrostatic potential map (MEP), Mulliken atomic charges, natural bond orbitals (NBO), electron localization function (ELF), localized orbital locator (LOL), quantum theory of atoms in a molecule (QTAIM) and noncovalent interactions—reduced density gradient (NCI-RDG) were studied for DPA and its inclusion complexes using the Gaussian 09 W software and Multiwfn 3.8 tool. [ABSTRACT FROM AUTHOR]

In this present work, a dumbbell-shaped ZnO nanostructure was successfully synthesized by a hydrothermal method through optimized hydrothermal temperature (200°C). The XRD showed the formation of the hexagonal crystalline structure with high-phase purity. The FE-SEM images of ZnO prepared at a hydrothermal temperature of 200°C exhibits a well-defined, monodispersed dumbbell-shaped morphology. The chemical surface states were investigated using XPS. The prepared ZnO-based anode material was tested using a 1M Na2SO4 aqueous electrolyte with a three-electrode cell configuration. The ZnO 200°C electrode materials delivered a high specific capacitance of 316 F/g at 1 A/ and columbic efficiency of 96% and capacitance retention of 92% after 10,000 cycles at the current density of 10 A/g. Due to its inherent properties, the maximum degradation efficiency of 91% for 180 min was obtained from a dumbbell-shaped ZnO (200°C) sample. The ZnO nanostructured materials suggest potential applications for supercapacitors and textile wastewater treatments. [ABSTRACT FROM AUTHOR]

In sequestration of CO2 in deep saline aquifers, the relative permeability of the immiscible fluids plays a crucial role in governing dissolution and capillary trapping mechanisms. Relative permeability is solely dependent on capillary pressure and saturation at that instant of time, whereas the capillary pressure dynamically changes during flow reversal resulting in the hysteresis behavior of the relative permeability curves. However, the conventionally used models equate relative permeability as an explicit function of saturation, neglecting the inherent physics that govern the immiscible displacement of fluids. On the other hand, upscaling the pore scale mechanisms, such as contact angle hysteresis and wettability characteristics, to Darcy scale remains complicated. In the present investigation, an attempt has been made in formulating a methodology to compute relative permeability of the phase fluids based on contact angle hysteresis. The relative permeability curves calculated using the present model have been compared with that computed using existing methodology present in the literature. It has been observed that the present relative permeability model effectively calculates the drainage and imbibition relative permeability of both the wetting and non-wetting phases in the porous system. [ABSTRACT FROM AUTHOR]

Arsenic present in water bodies causes devastating effects on aquatic organisms and indirectly poses a hazardous threat to human existence. There is an urgent need to develop potential and convincing technologies to troubleshoot this problem. In the present study, an adsorbent has been prepared using the waste red mud from hazardous aluminium industry and doping it with calcium-alginate beads (ARMCB) for the effective removal of As(III) from wastewater. The concentration of As(III) was reduced from 0.101 mg/L to 0.008 mg/L after adsorption which effectively met the economic and environmental conditions imposed by WHO (>0.01 mg/L). Further, the statistical Response Surface Methodology (RSM) is adopted to analyze the combined effects of four operational parameters namely: pH, sorbent dosage, contact time and initial concentration on the adsorption of As(III) from the synthetic contaminated water samples. A high correlation coefficient (R2) value of 0.9672 projected by ANOVA confirmed the satisfactory regression of the developed model. The maximum adsorption capacity is found to be 1.807 mg/g at optimum operating conditions. The surface characterization of the adsorbent before and after adsorption by SEM, EDX, XRD, and FTIR confirms the potentiality of the adsorbent towards As(III) ions. Thermodynamic, adsorption isotherms and kinetic analysis respectively projected the endothermic Langmuir model adsorption of As(III) and the pseudo-second-order rate kinetics of the sorption mechanism. The current study aids the implementation of the developed robust technique for the successful removal of As(III) from industrial and domestic polluted water samples. [ABSTRACT FROM AUTHOR]

During microbial enhanced oil recovery (MEOR) processes, the interaction between injection water (IW) and formation water (FW) salinity causesin-situsalinity variation which affects the final oil recovery. The present study explicitly quantifies the Original Oil in Place (OOIP) recovered for different IW and FW salinity conditions through numerical simulation. Based on simulation results, user-friendly empirical correlations were deduced to quickly estimate the OOIP. The results suggest that the OOIP increases drastically in all reservoirs with any initial FW salinity as the adopted salinity of IW is lowered. The study would serve as a tool for making reservoir management decisions. [ABSTRACT FROM PUBLISHER]

Considerable uncertainty occurs in the parameter estimates of traditional rainfall–water level transfer function noise (TFN) models, especially with the models built using monthly time step datasets. This is due to the equal weights assigned for rainfall occurring during both water level rise and water level drop events while estimating the TFN model parameters using the least square technique. As an alternative to this approach, a threshold rainfall-based binary-weighted least square method was adopted to estimate the TFN model parameters. The efficacy of this binary-weighted approach in estimating the TFN model parameters was tested on 26 observation wells distributed across the Adyar River basin in Southern India. Model performance indices such as mean absolute error and coefficient of determination values showed that the proposed binary-weighted approach of fitting independent threshold-based TFN models for water level rise and water level drop scenarios considerably improves the model accuracy over other traditional TFN models. EDITOR D. Koutsoyiannis ASSOCIATE EDITOR A. Fiori [ABSTRACT FROM AUTHOR]

This work presents a compositional numerical model to simulate the combustion of heavy crude oil in a porous combustion tube. The combustion tube experiments replicate an enhanced oil recovery process by in-situ combustion (ISC) of crude oil in a petroleum reservoir. Due to the economic constrains associated with the combustion tube tests, numerical simulation has been identified as an efficient and economical tool in understanding the complex ISC process. In the present model, mass and energy conservations have been drawn considering an advective, diffusive, and reactive flow of multiple components in multi-phase. The model includes temperature- and pressure-dependent fluid properties and considers the effect of capillary pressure. A block-centered finite-difference-based numerical tool with an implicit quasi-Newton iterative solver scheme has been developed to solve the conservation equations. The numerical model is validated with the combustion-tube results reported by Fadaei et al. (2011). The combustion front profile predicted by the present numerical model has been found to be in good agreement with the reported results. The numerical results projected a cumulative oil recovery of about 60% of original oil in place. The combustion front has been found to propagate with an average peak temperature of 715 K. [ABSTRACT FROM PUBLISHER]

Nutraceuticals availability in heat-processed foods is considered to be the index for healthy food. This study has made an attempt to optimize the temperature to retain nutraceuticals in wheat bran (WB) and wheat germ (WG). Heated WG (130 °C & 140 °C) and WB (140 °C & 150 °C) were analyzed for sensory profiles. Extracted oils were subjected to physicochemical parameter as well as its nutraceuticals. Increased oil yield, color values and reduced free fatty acids were found with varied temperatures. Fat-soluble compounds total tocols, steryl ferulates and carotenoids found in WG (0.316, 0.058 and 0.011%) and WB (0.228, 0.595 and 0.015%) and maximum reductions started in WG (0.183%, 0.034% and 0.004%) at 130 °C. The free radical-scavenging activities of control samples showed high EC50 values than processed samples; however, no differences were observed between two temperatures. Study may clearly spell out that the reduced nutraceuticals observed after subjecting food raw materials to optimum temperature eventually lead to its quality. [ABSTRACT FROM AUTHOR]

This paper presents outcomes of a cross-sectional study conducted in Kerala, India on the parenting practices of 0-3-year-old children supported by UNICEF. The aim of the study was to explore early child-care practices from conception to 3 years with a focus on the family as caregiver. Positive attitudes were observed in key indicators of child-rearing practices among the study population. No major difference was observed among women of various sociodemographic backgrounds in this respect. Early child-care practices are reaching high standards, even in tribal and economically backward areas. This may be an indicator of the overall achievement of Kerala in general health status. Even though parenting practices are generally healthy, as revealed through focus-group discussions, parents face many problems in child rearing and would benefit from training in parenting practices. [ABSTRACT FROM AUTHOR]