Adsorption potential of ionic liquid-modified ZnO nanoparticles for highly efficient removal of azo dye: detailed isotherms and kinetics.

In this study, bare and ionic liquid-modified ZnO nanoparticles have been fabricated using microwave irradiation method. The fabricated nanoparticles were characterized by different techniques, viz. XRD, FT-IR, FESEM, and UV-Visible spectroscopy, and were explored as adsorbent for effective sequestration of azo dye (Brilliant Blue R-250) from aqueous media. Various factors affecting the adsorption efficiency of synthesized nanoparticles (bare/ionic liquid-modified) such as concentration of dye, pH of reaction media, dose of nanoparticles, and reaction time were thoroughly investigated with varying experimental conditions; on a magnetic stirrer and in a sonicator. The results exhibited a high adsorption efficiency of ionic liquid-modified nanoparticles for removal of dye as compared to the bare one. Also, an enhanced adsorption was observed via sonication in comparison with magnetic stirring. Different isotherms such as Langmuir, Freundlich, and Tempkin were elaborated. Evaluation of adsorption kinetics showed a linear pseudo-second-order equation for adsorption process. The exothermic and spontaneous nature of adsorption was further confirmed by thermodynamic investigations. As per the results obtained, it is suggested that the fabricated ionic liquid-modified ZnO nanoparticles could successfully remediate the toxic anionic dye from aqueous media. Hence, this system can be utilized for large-scale industrial applications.

A comprehensive review on the metal-based green valorized nanocomposite for the remediation of emerging colored organic waste.

In today's era, "green" synthesis is an emerging research trend. It has gained widespread attention owing to its dynamic behavior, reliability, simplicity, sustainability, and environment friendly approach for fabricating various nanomaterials. Green fabrication of metal/metal oxides nanomaterials, hybrid materials, and other metal-based nanocomposite can be utilized to remove toxic colored aqueous pollutants. Nanomaterials synthesized by using green approach is considered to be the significant tool to minimize unwanted or harmful by-products otherwise released from traditional synthesis methods. Various kinds of biosynthesized nanomaterials, such as animal waste and plant-based, have been successfully applied and well documented in the literature. However, their application part, especially for the cure of colored organic polluted water, has not been reported as a single review article. Therefore, the current work aims to assemble reports on using novel biosynthesized green metal-based nanomaterials to exclude harmful dyes from polluted water.

Silver embellished PANI/CNT nanocomposite for antimicrobial activity and sequestration of dye based on RSM modelling.

Silver doped PANI/CNT (Ag-PANI/CNT) nanocomposite was synthesized and investigated as adsorbent for its possible application in the elimination of organic dye Brilliant Blue G (BBG). The morphological characteristics of Ag-PANI/CNT were studied using Fourier transform infrared, scanning electron microscopy, elemental mapping, transmission electron microscopy and X-ray diffraction. The response of operational parameters given as adsorbent dosage, concentration, pH and contact time for dye removal were investigated by using Response Surface Methodology (RSM). The results from RSM suggested that the efficiency of BBG elimination is 98.7 under the optimum conditions of experimental factors. The adsorption studies showed that the equilibrium data fitted well with Langmuir isotherm model compared to Freundlich. Finally, the antimicrobial activities of Ag-PANI/CNT were tested against bacterial strain Escherichia coli and Salmonella typhi and fungal strains Aspergillus niger.

Preferential and Enhanced Adsorption Ability of ZrO2 Nanoparticles for the Removal of Cationic, Anionic and Azo Dyes: Isotherm and Kinetic Studies.

Adsorption of Coomassie Brilliant Blue R-250, Congo Red and Acridine Orange from aqueous solution has been examined using ZrO2 nanoparticles, which proved to be a novel adsorbent. ZrO2 nanoparticles have been prepared by simple chemical precipitation method. The characterization of ZrO2 nanoparticles has been carried out by UV-vis spectroscopy, FTIR, XRD, TEM and FESEM. ZrO2 nanoparticles were found tetragonal in structure, spherical in morphology, and illustrated constricted size window (8-12 nm). The findings depicted that adsorbate removal on ZrO2 nanoparticles was affected significantly by change in adsorbent dose, pH and initial dye concentration w.r.t to contact time. The isotherms were well elaborated using Langmuir and Freundlich adsorption isotherms. The adsorptive kinetics was also investigated with pseudo-second-order to evaluate constant corresponding to rate. Moreover, the ZrO2 nanoparticles along with adsorbed dyes were desorbed. The identities of recovered nanoparticles as well as the adsorbed dyes were found to be same.

Regional hippocampal damage in heart failure.

AIMS: Heart failure (HF) patients show cognitive and mood impairments, including short-term memory loss and depression, that have an adverse impacting on quality of life and self-care management. Brain regions, including the hippocampus, a structure significantly involved in memory and mood, show injury in HF, but the integrity of specific hippocampal subregions is unclear. METHODS AND RESULTS: To assess regional hippocampal volume loss, we evaluated 17 HF patients (mean age ± SD, 54.4 ± 2.0 years; 12 male, left ventricular ejection fraction 28.3 ± 6.8%; New York Heart Association class II/III 94%/6%) and 34 healthy control subjects (52.3 ± 1.3 years; 24 male) using high-resolution T1-weighted magnetic resonance imaging and evaluated localized surface changes with morphometric procedures. Hippocampi were manually outlined, and volumes calculated from normalized tracings. Volume differences between groups were assessed by two-sample t-tests, and regional differences were assessed by surface morphometry. Patients with HF exhibited smaller hippocampal volumes than controls (right 3060 ± 146 mm(3) vs. 3478 ± 94 mm(3), P = 0.02; left 3021 ± 145 mm(3) vs. 3352 ± 98 mm(3), P = 0.06). Volume reductions were detected principally in CA1, an area integral to an array of learning and memory functions, as well as in mid to posterior CA3 and subiculum. CONCLUSION: The hippocampus shows regional volume reduction in HF, which may contribute to short-term memory loss and depression associated with the condition.

Ultra fast and effective treatment of dyes from water with the synergistic effect of Ni doped ZnO nanoparticles and ultrasonication.

The current research work focuses on the synergistic effect of Ni doped ZnO nanoparticles and ultrasonication for the degradation of anionic (Fast Green) and cationic (Victoria Blue) dyes. Well crystalline monodispersed Ni doped ZnO nanoparticles have been synthesized by quick and simple co-precipitation technique at low temperature. Synthesized nanoparticles have been characterized by X-ray diffraction, UV-vis spectroscopy, transmission electron microscopy and energy dispersive X-ray spectroscopy. The effects of operating parameters such as catalyst dosage, pH, power dissipation, temperature and dye initial concentration have been investigated, and the enhancement in degradation capability of Ni doped ZnO with undoped ZnO has also been discussed. The degradation of both the dyes follows pseudo-first-order kinetics. In concert with superior activity and reuse performance, the current route is promising for the application of ZnO-based catalysis for water decontamination.

Gamma-Fe2O3 nanospindles for environmental remediation: a study on the adsorption and desorption characteristics of acridine orange and direct red dyes.

In this paper, the adsorption and desorption characteristics of two harmful dyes, i.e., acridine orange (AO; cationic dye) and direct red 81 (DR; anionic dye) from aqueous solutions onto gamma-Fe2O3 nanospindles have been investigated. The nanospindles were synthesized by facile chemical precipitation method and characterized in detail in terms of their morphological, compositional and optical properties. Batch mode experiments were conducted to examine the adsorption process by investigating several factors such as effect of pH, amount of adsorbent dose, and effect of dye concentrations. The experimental results indicated that the maximum adsorption capacity occurred at pH = 6.0 for AO and at pH = 4.0 for DR, respectively with 0.03 gm of adsorbent. Langmuir, Freundlich, Temkin, and Dubinin-Radushkevich isotherm models have been used to evaluate the ongoing adsorption. Kinetic parameters for the adsorption have also been applied. Moreover, the gamma-Fe2O3 nanospindles and the adsorbed dyes were desorbed with good performance and could be reused to absorb the dyes again.

Removal of water contaminants by iron oxide nanomaterials.

In recent years, there has been increasing concern about the usage of a broad range of organic substances, heavy metals and aromatic compounds in the aquatic environment due to their wide distribution and potential adverse health effects. The presence of toxic contaminants in water effluent, even at very low concentrations, is extremely harmful and undesirable. Various treatment processes have been investigated to reduce these toxic pollutants from wastewater. Because of the chemical stability of the contaminants, these technologies have proved to be ineffective for handling waste effluents. Nanotechnology offers the possibility of efficient removal of pollutants as nanoparticles have a smaller size and higher adsorptive surface area. From the past few years, nanoscale iron oxides such as magnetite, maghemite, and hematite have been used for the separation and removal of organic and inorganic contaminants. In this review we summarize the use of iron oxide nanomaterials performed over the last few years for the removal of dyes, heavy metals and aromatic compounds.

Adsorption studies of cationic, anionic and azo-dyes via monodispersed Fe3O4 nanoparticles.

The present paper reports the applicability of magnetite (Fe3O4) nanoparticles as an adsorbent for the removal of three dyes viz. Acridine orange (cationic dye), Comassie Brilliant Blue R-250 (anionic dye) and Congo red (azo dye) from their aqueous solution. The Fe3O4 nanoparticles were synthesized via simple chemical precipitation method using CTAB, as surfactant. The as-prepared nanoparticles were characterized in terms of their morphological, structural and optical properties by using transmission electron microscopy X-ray diffraction and UV-visible spectroscopic measurements. The dye removal efficiency of Fe3O4 NPs have been determined by investigating several factors such as effect of pH, amount of adsorbent dose and effect of contact time on different dye concentrations. Langmuir and Freundlich adsorption isotherms have also been studied to explain the interaction of dyes. The experimental data indicate that the adsorption rate follows pseudo- second-order kinetics for the removal of all the three dyes. Moreover, the nanoparticles and the adsorbed dyes were desorbed. The identities of recovered nanoparticles as well as the three dyes have been found, as same and were reused.

Three-dimensional mapping of hippocampal and amygdalar structure in euthymic adults with bipolar disorder not treated with lithium.

Structural neuroimaging studies of the amygdala and hippocampus in bipolar disorder have been largely inconsistent. This may be due in part to differences in the proportion of subjects taking lithium or experiencing an acute mood state, as both factors have recently been shown to influence gray matter structure. To avoid these problems, we evaluated euthymic subjects not currently taking lithium. Thirty-two subjects with bipolar type I disorder and 32 healthy subjects were scanned using magnetic resonance imaging. Subcortical regions were manually traced, and converted to three-dimensional meshes to evaluate the main effect of bipolar illness on radial distance. Statistical analyses found no evidence for a main effect of bipolar illness in either region, although exploratory analyses found a significant age by diagnosis interaction in the right amygdala, as well as positive associations between radial distance of the left amygdala and both prior hospitalizations for mania and current medication status. These findings suggest that, when not treated with lithium or in an acute mood state, patients with bipolar disorder exhibit no structural abnormalities of the amygdala or hippocampus. Future studies, nevertheless, that further elucidate the impact of age, course of illness, and medication on amygdala structure in bipolar disorder are warranted.

Hippocampal volume is related to body mass index in Alzheimer's disease.

Obesity is associated with lower brain volumes in early Alzheimer's disease, but its effects on hippocampal volumes are unclear, as weight loss is also associated with Alzheimer's disease. To address this question, we applied an automated hippocampal mapping method to brain MRI scans for 162 patients with Alzheimer's disease. We hypothesized that obesity, measured by body mass index, would be associated with lower hippocampal volumes in mildly affected patients. Statistical maps showed a selective pattern of hippocampal volume differences that were significantly associated with body mass index. Associations were detected in the anterior hippocampus, and confirmed by permutation testing. Cardiovascular risk factors, such as high body mass index, may promote additional neurodegenerative changes, and should therefore be considered in epidemiological studies and clinical trials.

VENTRICULAR MAPS IN 804 SUBJECTS CORRELATE WITH COGNITIVE DECLINE, CSF PATHOLOGY, AND IMMINENT ALZHEIMER'S DISEASE.

There is an urgent need for neuroimaging biomarkers of Alzheimer's disease (AD) that correlate with cognitive decline, and with accepted measures of pathology detectable in cerebrospinal fluid (CSF). Ideal biomarkers should also be able to predict future decline, and should be computable automatically from hundreds to thousands of images without user intervention. Here we used our multi-atlas fluid image alignment method (MAFIA [1]), to automatically segment parametric 3D surface models of the lateral ventricles in brain MRI scans from 184 AD, 391 MCI, and 229 healthy elderly controls. Radial expansion of the ventricles, computed pointwise, was correlated with measures of (1) clinical decline, (2) pathology from CSF, and (3) future deterioration. Surface-based correlation maps were assessed using a cumulative distribution function method to rank influential covariates according to their effect sizes. The resulting approach is highly automated, and boosts the power of fluid image registration by integrating multiple independent registrations to reduce segmentation errors.