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Image analysis and spectroscopic method of evaluation are applied on Gamma auto radiographs (GAR) to assess the effect of plutonium concentration in (U,Pu)O2 mixed oxide (MOX) fuel samples on the characteristics of the irradiated film. Results of the two different methods of GAR analysis are compared with results of the earlier studies using alpha irradiated solid state nuclear track detectors using Pu bearing fuel samples with low as well as high plutonium content. Theoretical simulations using Monte Carlo method of radiation transport were carried out for comprehension of the process of GAR under ideal conditions and results were applied for understanding the relative degree of heterogeneity in Pu bearing fuel samples and compared with that from experimental methods of analysis.

Accurate, precise, and rapid analytical monitoring of various nuclear materials is essential for the smooth functioning of nuclear reactors. Ion chromatography (IC) has emerged as an effective analytical tool for simultaneous detection of different ions in a wide range of materials used in the nuclear industry. The major advantages over other techniques include superior selectivity and sensitivity for detection of anions and cations, wide dynamic range, and speciation studies of ions. This article provides an overview of different ion chromatographic methodologies developed for the analyses of various nuclear materials such as fuel, control rods, moderator, coolant, and process streams. Comparison of various analytical aspects of IC over the other routine techniques reveals the ease and multidimensional capability of the technique. An insight is given to the modern variations in the field such as coupling of IC with other techniques for the characterization of nuclear matrices, implementation of capillary IC in terms of miniaturization, and so on. The information presented herein will serve as a very useful resource for investigators in the field of characterization of nuclear materials.

Synthesis of Mo-substituted CeVO4 systems by facile co-precipitation process is reported wherein an upper solubility limit of 40 mol% Mo was obtained retaining the tetragonal structure. Solid solution formation was investigated by X-ray diffraction, X-ray fluorescence and Raman spectroscopy and XPS. Introduction of Mo into the anionic framework yielded hierarchical mesoporous structures with substantial increase in surface area from 76 to 147 m2/g as exhibited by TEM and BET analysis. Complete uptake of Pb2+ ions from aqueous solutions was shown by both CeVO4 and Mo-CeVO4 with sorption capacity of 100 mg/g. In addition, the presence of Mo in CeVO4 depicted five times faster and superior kinetics than pure CeVO4. Various isotherms have been used to model the data. This study not only unravels the structural aspects of Mo-substituted CeVO4 system but also discusses new promising sorbents for toxic Pb2+ ions obtained by simple synthetic route.

The use of any new extractant requires the study of its tendency to form third phases. To understand the phase separation process it is important to have knowledge of the molecular scale phenomena present in the system. This includes the mixing of the substances and the behavior and nature of the aggregates. Here we report the mixing properties of N,N,N′,N′-tetra-(2-ethyl hexyl) diglycolamide (TEHDGA)–dodecane–isodecanol (in the absence and presence of micellar aggregates) which is recognized as a promising system for the separation of minor actinides through the conventional solvent extraction route. The nature of interactions between TEHDGA and isodecanol was investigated using several techniques, including density and speed of sound measurements, ultraviolet absorption spectroscopy and computational studies. The TEHDGA–isodecanol interaction was found to be favored over the inter-isodecanol interaction. On equilibrating the organic phase with nitric acid, some indication of pre-micellar aggregation was obtained. Increase of micellar aggregate size on addition of isodecanol was indicated.

A simple, rapid, and accurate method for the determination of trace level anionic impurities of fluoride and chloride in nuclear grade boron carbide and elemental boron is presented. The me...

The surface functionalization of ZnO nanoparticles (ZnO NPs) was carried out by a simple one pot co-precipitation method followed by a facile ligand introduction onto the surface. This technique al...

(U,Pu)O2 mixed oxide (MOX) fuel has been irradiated in thermal as well as fast reactors in India for Pu utilization. MOX fuels are conventionally fabricated through the powder metallurgical route in conformance with the quality specifications. Homogeneity of fissile material in MOX fuel is a crucial characteristic which affects its performance in reactor as well as post irradiation dissolution for reprocessing. The relative richness and spatial extent of Pu rich agglomerates in the fuel matrix are the two important parameters to be controlled during fabrication to ensure homogeneity in the fuel. Gamma auto radiography is one of the routinely used inspection techniques for quality control of PFBR fuels for homogeneity. A new method based on image analysis and spectrophotometric analysis of the gamma auto radiographs has been developed for quantitative characterisation of fuel heterogeneity. The method could be used to estimate the relative Pu richness and size of the agglomerate in the fuel.

Determination of trace level of iron in metallic uranium is of great importance. The developed procedure involves online pre-concentration and separation of iron and its determination using flow injection analysis system. The analyte forms complex with mandelic acid and retained in the micro column packed with cation exchanger and matrix goes to waste. The eluted iron was determined and the detection limit of the method is 5 ppb with a precision (RSD) at 100 ppb level of 6.2%.

Radiation imaging using solid state nuclear track detectors is an important non destructive technique for estimation of radioactive species like plutonium, thorium etc. In this study, two alpha sources were used for imaging of alpha tracks. From the image analysis of the tracks, different track characteristics were analysed. The frequency distribution of track parameters is Gaussian in nature and is found to be affected by the energy of alphas. It was seen that the maximum of the frequency distribution was located at higher values of track diameter (or area) for the tracks registered with alphas of higher energy. This could be attributed to greater extents of structural changes within the polymer upon impingement of alphas with higher energy. The studies could prove to be a marker for the identification of alpha sources of different nuclides.

Analytical evaluation of the effect of alpha fluence and energy on the properties of the irradiated PADC polymers was carried out. The images obtained by alpha irradiation on the films were analyzed using image analysis technique while UV–Vis spectrophotometry was used to understand the changes of the optical properties of the polymer. The results of this study could be applied for estimation of fluence and identification of energy of plutonium bearing sources in nuclear industrial facilities without having to use a dedicated and glove box enclosed equipment.

New methods for estimation of concentration and distribution of plutonium in (Th,Pu)O2 MOX fuel samples have been attempted by spectroscopic analysis of SSNTD based alpha images using UV–Vis spectrophotometry and photoluminescence spectroscopy. (Th,Pu)O2 MOX fuel samples having a large range of PuO2 concentration, were subjected to this study and found beneficial when compared with the conventional analysis of alpha autoradiographs. UV–Vis absorbance and photoluminescence of the alpha autoradiograph showed linear decrease proportionally to PuO2% in the fuel sample. Optical band gap was found to proportionally increase with PuO2% in the fuel sample which was revealed in UV–Vis spectrophotometry.

Evaporation induced assembly of colloidal particles in an aerosol droplet has been utilized to synthesize nano-structured porous silica microcapsules comprising of interlocked correlated nano-particles. Morphology of the microcapsules was tuned by controlling the rate of evaporation. In the present work, we demonstrate that such porous capsules can efficiently take up cationic dye from aqueous solution. In-situ UV–vis spectroscopy has been utilized to monitor the time dependence of sorption by these capsules. Small-angle X-ray scattering and scanning electron microscopy have been used to probe the multi-level structure of the powder granules. Thermal analysis was performed on the dye-sorbed granules to investigate the effect of confinement on the thermal degradation behaviour of the dye molecules within the granules.

Nitrate (NO3−) is one of the most common contaminants of water bodies with harmful effects to aquatic life and human beings. There is a need for development of sorbents for effective removal of NO3− form aqueous streams. The aim of present study was to develop a Polyaniline modified halloysite nanoclay (PAni-HC) composite sorbent for the uptake of NO3− from aqueous medium. Aniline coated on halloysite clay was oxidised in acidic medium at 4ºC to synthesise PAni-HC composite in one pot reaction. Successful incorporation of polyaniline (PAni) in the clay matrix was confirmed by different surface characterisation techniques. The as synthesised PAni-HC composite sorbent was tested for NO3− sorption in a batch mode in the initial concentration range of 5–500 mg L−1. The analysis of NO3− was performed using ion chromatography in the suppressed conductivity mode. The experimental data were assessed using different kinetic and equilibrium models for understanding the sorption behaviour of the PAni-HC composite. Sorption followed pseudo second order kinetics and intraparticle diffusion model. The maximum Langmuir sorption capacity of PAni-HC composite for NO3− was found to be 27.9 mg g−1. The composite sorbent when treated with groundwater samples exhibited quantitative removal (> 90%) of NO3−thus demonstrating the applicability of the sorbent in real situations.

The present study aims to probe the effect of silver nanoparticles (AgNPs) on the sorption behaviour of boroaluminosilicate glass (BASG). Firstly, BASG was loaded with AgNPs and benzotriazole (BT) and the glass exhibited surface-enhanced Raman spectrum of BT. The loaded BASG was equilibrated with copper (II) chloride solution and was investigated using ICP-AES, Raman spectroscopy, and luminescence measurements. It was observed that the glass matrix along with the sorbed copper ions showed luminescence, with a broad peak centered at ∼400 nm, indicating the presence of copper ions in the Cu (I) state. However, in the absence of AgNPs, the glass matrix containing BT and sorbed copper ions failed to show luminescence implying that the copper ions are in the Cu (II) state. The glass matrix containing copper ions in addition to AgNPs and BT gave an enhanced Raman peak at 240 cm −1 (corresponding to Ag-Cl stretch with overlapping Ag-N stretch mode) and a shift of peak from 1022 (inplane trigonal ring breathing mode) to 1040 cm −1 and a broadening of the ring stretching modes at 1390 and 1575 cm −1 . All these observations could be attributed to the interaction of copper ions with BT and the simultaneous uptake of chloride ions along with copper. The studies suggest that both AgNPs and copper ions bind to the nitrogen atoms of BT and form a nanoarray like assembly AgNPs-BT-Cu which facilitates the diffusion/tunnelling of electrons from AgNPs to Cu (II) ions resulting in the reduction of Cu (II) to Cu (I).

Titanium di-oxide (TiO 2 ) nanotubes (NTs) based solar cells are currently analyzed for the high efficiency solar cell devices due to its efficient electron transport. In this context, the present review deals about the recent advances made through the semiconductor nanoparticles sensitization on well aligned, vertically oriented TiO 2 NTs for fabrication of high efficiency third generation solar cells architecture. This review also deals with the efficient methods which are currently used to sensitize TiO 2 NTs by semiconductor nanoparticles. Special attention has been paid to the sensitization effect of cadmium chalcogenides based nanoparticles (CdS, CdSe, CdTe) on TiO 2 nanotubes in improving the efficiency of the solar cell. The expectations on TiO 2 NTs to face the 20 Terawatt (20 TW) challenge is examined.

Iron oxide-silica nanocomposite synthesized by one-pot co-precipitation method was evaluated for its applicability as sorbents for removal of toxic species like inorganic metal ions (UO22+, Zn2+, Cu2+, Ni2+, Co2+) and cationic dyes (MB and R6G) from aqueous streams at room temperature. The detailed structural analysis revealed the formation of crystalline iron oxide core with amorphous silica shell. The zeta potential measurements of surface charge helped in assessing the applicability of the sorbents. The magnetic property of the sorbent, as evaluated from magnetic measurements helped in its easy separation from solution using external magnetic field. The high porosity and large surface area of sorbent contributed to its excellent sorption efficiency. The efficiency of magnetic nano-composites was analyzed with respect to sorption kinetics (rate and kinetics order), initial concentration of toxic species (equilibrium conditions) and weight of sorbent. The optimum pH for uptake was in the range of 5–6. Extensive modelling of sorption data helped in getting an insight to the mechanism of metal ion sorption. The selectivity towards uptake of MB (MB) as opposed to that of Rhodamine 6G (R6G) was quite intriguing and detailed studies were carried out to understand this. Since the bare nanosorbent showed no selectivity in sorption of metal ions, modification was carried out to enhance selectivity with respect to uranyl ion.

The surface charge of nanosorbents is a very important factor which affects applications. In the present paper, the surface charge of ZnO NPs was tailored using by adopting different synthesis protocols. The synthesized nanoparticles were characterized and zeta potential measurements showed that the ZnO Nps synthesized by pyrolysis method (ZnO (PY)) and the gel-combustion method (ZnO (GC)) possess a positive charge while the co-precipitation method results in nanoparticles (ZnO (CP)) with negative surface charge.

CR is a commercially available Poly allyl diglycol carbonate PADC detector which has very high efficiency in registering alpha tracks from radio nuclides nbsp Optical properties of CR have been found to change in correlation with the alpha fluence incident upon it nbsp UV Vis spectroscopic studies have been carried out to understand these changes in alpha irradiated CR SSNTDs and these correlations were effectively applied for identification of radioactive Pu isotopes nbsp

Luminescent cadmium telluride nanoparticles were synthesized from the reaction intermediate tellurium nanorods as tellurium source at 100 °C through colloidal approach. Oxyanion source of tellurium, (i.e.) potassium tellurite (K 2 TeO 3 ) was used as precursor to synthesize the tellurium nanorods under the low temperature process without any surfactant in various volumes of water. Thioglycolic acid (TGA) was employed as capping agent for the synthesis of CdTe nanoparticles. Absorption and emission spectra of the prepared nanoparticles clearly indicate the size dependent nature of the particles. SEM and EDX analyses of the nanorods reveal the shape of the synthesized nanorods and the presence of elemental tellurium without any impurities. XRD analysis of the prepared samples confirms the existence of trigonal phase of tellurium nanorods (t-Te) and the formation of CdTe particles with cubic zincblende structure. The size distribution of the prepared CdTe nanoparticles was analyzed through TEM analysis. It was found that considerable influence of solvent on morphology of the synthesized tellurium nanorods. The synthesis mechanism of one dimensional structure as seeds for zero dimensional nanoparticles was analyzed.

n-Benzoyl-n-phenylhydroxylamine impregnated Amberlite XAD-4 beads were used for the removal of Th(IV) from a mixture of ions. The impregnated XAD was characterized using different techniques like weight and colour change, IR spectra, surface area and pore size measurements to confirm the presence of n-BPHA within the macroreticular resin structure. The experimental conditions were optimized to make the separation fast and selective. It was seen that the maximum sorption was achieved in the pH range of 3–7.5 and uptake was nearly complete within half an hour. The results obtained in the present study were subjected to extensive modelling in order to get a complete understanding of the sorption process. It is seen that the maximum uptake was calculated to be 500 mg/g and has very fast kinetics it was seen that the process is chemisorption. It was further deduced from the modelling that the overall sorption process was controlled dominantly by external mass transfer. Considering the simplicity this procedure, the present study has a possible application for the removal of thorium from different mixtures.

Cadmium selenide (CdSe) nanoparticles were synthesized in aqueous medium using mercaptopropionic acid (MPA) as the stabilizer at the temperature 100 °C. Air stable sodium selenite (Na2SeO3) was used as the selenium source. The synthesized particles were used to co-sensitize the TiO2 nanotubes with N3 dye. Ex-situ linker assisted method was used to sensitize the nanotubes by CdSe nanoparticles. Electrochemical anodization technique was employed to prepare TiO2 nanotubes in the presence of hydrogen fluoride (HF) as electrolyte. A solar cell was fabricated using co-sensitized TiO2 nanotubes by N3 dye/CdSe nanoparticles as the anode and platinum coated fluorine doped tin oxide (FTO) electrode as the cathode. Polysulphide ( S 2 - / S x 2 - ) mixture was used as the electrolyte. UV–Visible, SEM, AFM and TEM analysis were used to characterize the synthesized particles and TiO2 nanotubes.

Luminescent CdTe nanoparticles were synthesized in aqueous medium at low temperature under the inert atmosphere using water soluble precursors. Potassium tellurite was employed as the tellurium source for the synthesis. As synthesized CdTe nanoparticles were phase transferred into organic medium via partial ligand exchange method through long chain organic ligand 1-dodecanethiol in the presence of acetone. The phase transferred CdTe nanoparticles were blended homogeneously with P3HT polymer in a common solvent (chloroform) for possible application as the active layer in hybrid solar cell structure. The prepared blends were characterised with UV–Vis, Photoluminescence, SEM and AFM analysis. The XRD patterns of the particles in two phases confirm the uniformity of the cubic structure. The size distribution of the synthesized particles was confirmed through TEM analysis. The effective interactions of the donor and acceptor components were confirmed through UV–Visible spectroscopy. The efficient charge transfer processes of the blends were confirmed through photoluminescence analysis of the nanoparticles various volume additions with polymer. The morphological analysis of the blends was carried out using the Scanning Electron Microscopy which reveals the distribution of the nanoparticles in the polymer. AFM analysis of the coated blend film explores the phase separation of the nanoparticles when blended with the polymer in chloroform. Advantages of these nanoparticles for solar cell applications were discussed.

Ethylenediamine capped CuInSe 2 nanoparticles were synthesized by wet chemical method at room temperature and hydrothermal method at 150 °C for 2 h at two different mole ratio of the capping agent. The effect of the synthesis method and ratio of the capping agent on the optical, structural, and morphology of the synthesized nanoparticles were analyzed. The optical property of the synthesized nanoparticles was estimated from the UV–Vis spectra and also from the emission spectra. The surface capping was confirmed through the FT-IR. Powder XRD analysis reveals that the nanoparticles exhibit wurtzite phase and the crystallinity increases while increasing the capping ratio and hydrothermally synthesized nanoparticles show higher crystallinity. Raman analysis shows that the hydrothermally synthesized samples exhibit B 2 (LO) mode. The surface morphology was modified depending on the synthesis method and capping agent ratio (i.e.) rod like and cube like morphology were obtained for the hydrothermally synthesized nanoparticles with 5 and 10 mol ratio of the capping agents respectively.

Thioglycolic acid (TGA) capped cadmium selenide (CdSe) nanoparticles were synthesised in aqueous medium through wet chemical method using sodium selenite as the selenium source. The synthesised particles were transformed into organic medium using 1-dodecanethiol through efficient partial ligand exchange strategy. The UV–visible spectra recorded for the particles reveal the size distribution in water as well as in organic solvent. TEM analysis of the synthesised particles shows the size and the nature of distribution of the particles in solution. The phase transferred particles were blended with the polymer poly-3-hexyl thiophene (P3HT) in chloroform. UV–visible and photoluminescence spectra of the polymer with various volumes of the nanoparticles clearly indicate the effective coupling and the efficient charge transfer process in the blend. SEM analysis of the CdSe–P3HT blends confirms the effective distribution of the nanoparticles in the polymeric matrix. AFM studies reveal the morphology of the nanoparticles and the phase separation process in the blends.

MnWO4 and MnMoO4 nanoparticles have been synthesized using a facile sonochemical technique. The nanostructures were characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM) and nitrogen adsorption–desorption measurements. The as-prepared spherical MnWO4 and MnMoO4 nanostructures have a high specific surface area and their excellent adsorbent properties to remove organic pollutants have been demonstrated for the first time. Complete removal of dyes like Rhodamine B and Methylene blue was possible within 2–10 minutes. The influences including initial pH, dosage of adsorbent and contact time have been researched in order to find the optimum adsorption conditions. The experimental data were analyzed by the Langmuir and Freundlich adsorption models. MnWO4 also proved to be a good sorbent for Cu(II) ions. The kinetic modeling for Cu(II) sorption has been discussed. These studies showed that there is a possible application for the complete and fast removal of the organic dyes in the presence of inorganic cations using MnWO4/MnMoO4 sorbents. The thermal regeneration of the sorbents is possible and they show similar adsorption efficiency up to ten consecutive cycles. The sonochemically synthesized MnWO4 and MnMoO4 nanomaterials could serve as promising adsorbents for the removal of organic dyes, especially, cationic dye, and Cu(II) ions from polluted water.

The present work reports the development of new (sodium alginate-gelatin (SAG))-g-poly(acrylic acid)/polyaniline (SAPAPN) from sodium alginate/gelatin blend by cross-linking with glutaraldehyde, followed by grafting with poly(acrylic acid) and polyaniline by free radical polymerization using ammonium persulfate. The structure, thermal stability, and morphology of SAPAPN adsorbent was characterized by Fourier transform infrared spectroscopy, thermo gravimetric analysis, and scanning electron microscopy, and results were consistent with the expected structures. The influence of various experimental conditions like pH, time, and initial feed concentrations on the uptake of metal ions like Cu2+, Ni2+ by SAPAPN adsorbent was tested. It was seen that the adsorption equilibrium data could be fitted to the Langmuir isotherm. Desorption studies were performed in acid media and EDTA, to examine whether the SAPAPN adsorbent can be recycled for the metal ion removal. The results showed that with SAPAPN adsorb...

Antimony phosphate nanoribbons was synthesized and characterized using different techniques. Studies showed that the synthesized antimony phosphate possessed highly crystalline monoclinic SbPO4 phase with an average crystallite size of 14 nm. TEM studies showed that antimony phosphate was present both as nano ribbons and nano particles. It is observed that the nano ribbons have length in the range of 500–700 nm and width around 100–200 nm whereas the nanoparticles size in the range of 1–5 nm. The synthesized nano phosphate was studied for its efficiency as sorbent for uptake of various metal ions including uranyl ion. The results indicated that a clean separation of uranyl ion from its various binary mixtures could be achieved at optimized pH of 4.5 and equilibration period of 1 h using 0.1 g of the sorbent.

Polyaniline (Pani) was synthesized by the chemical oxidation of aniline. The use of persulphate instead of dichromate was desired in order to avoid the incorporation of chromium in the polymer matrix. The presence of chromium in the matrix, when dichromate was used as an oxidant, was confirmed by various techniques. The batch mode experiments showed that Pani could be used for separation of different metal ions. These ions were converted into their anionic complexes using suitable complexing agents. It was found that EDTA was used as a suitable reagent for the separation of Cu2+ from Zn2+ whereas the uranyl ion uptake could be increased to about 95 % when carbonate was used instead of EDTA as complexing agent. A possible application of the above exchange system to preconcentration of uranyl ion from seawater has also been examined.

Novel chitosan (CS) based membrane networks were developed by solution casting and followed by crosslinking with different crosslinkers such as glutaraldehyde, urea-formaldehyde, and thiourea-formaldehyde. The developed membrane networks were designated as CS-GA, CS-UF and CS-TF. Crosslinking reaction of CS membranes was confirmed by Fourier transform infrared spectroscopy. Membrane rigidity and compactness were studied by the differential scanning calorimetry. The surface morphology of CS membranes was characterized by scanning electron microscopy. The sorption behaviour with respect to contact time, initial pH and initial metal ion concentration were investigated. The maximum adsorption capacity of CS-GA, CS-UF and CS-TF sorbents was found to be 1.03, 1.2 and 1.18 mM/g for and 1.48, 1.55 and 2.18 mM/g for respectively. Swelling experiments have been performed on the membrane networks at . Desorption studies were performed in acid media and EDTA and it was found that the membranes are reusable for the metal ion removal for three cycles. The developed membranes could be successfully used for the separation of and metal ions from aqueous solutions.

Nanocrystalline manganese oxide was prepared and characterized using various techniques like XRD, surface area analyzer and zeta potential measurements. The sorption characteristics with respect to uptake of various ions including uranyl have been evaluated. Various experimental conditions which affect the sorption characteristics have been studied. Nanocrystalline manganese oxide was prepared by the hydrolysis of KMnO4 and the nano oxide were found to have a size of 8 nm and surface area of 145 m2/g. Due to the high surface area, the sorption property of the nano oxide was good. It was found that the sorption was achieved at different pH values and with varying time of equilibration. Thus it is seen that the kinetics was an important aspect for the possible separation of metal ions.

Solvent extraction is hoary yet modern technique with great scope of research due to the various intriguing phenomena in the system. Tri-n-butyl phosphate (TBP) is a well known extractant which has been extensively used for separation of uranium matrix prior to elemental profiling. In this paper, one of the impurities namely Fe is being considered as it posed a challenge to the separation due to its co-extraction with TBP along with uranium. In these studies, for the first time, the existence of cation-cation inner sphere complexes between the UO22+and Fe3+ ions in both aqueous and organic phases have been establisted in addition to the selective separation of iron from uranium sample matrix using only TBP. The data from both spectrophotometric and thermophysical studies corroborated one another confirming the presence of cation-cation interactions (CCIs). The developed solvent extraction with only TBP showed almost no interferences on the iron extraction from matrix uranium and other co-ions like aluminum and copper. This has been the first time application of pure TBP for selective removal of iron from uranium samples. The procedure possessed excellent reproducibility and robustness.

were prepared and char-acterized using various techniques like XRD, TEM, surface area analyzer and zeta potential mea-surements. The synthesized oxides were evaluated for their sorption characteristics with respect touptake of lead ion. It was found that depending on the nature of the oxide the maximum sorptioncould be achieved within varying periods of time. However, it was found that for all the sorption,the optimum pH was around 6. It was seen that the oxides could be used as room temperaturesorbents for uptake of Pb

Sodium boroaluminosilicate glasses, (Na2O)0.22(K2O)0.029(B2O3)0.05(SiO2)0.69(Al2O3)0.011 and (Na2O)0.05(K2O)0.029(B2O3)0.22(SiO2)0.69(Al2O3)0.011 having different B2O3 to Na2O mole ratio of 0.23 and 4.4 respectively were investigated for their uptake characteristics of cationic dyes, namely Rhodamine 6G and methylene blue, from aqueous solutions. Both the glasses have been found to adsorb these dyes. However, the glass with B2O3 to Na2O ratio of 0.23 is found to have more uptake capacity with 2.5 and 1.8 mmol of Rhodamine 6G and methylene blue respectively per gram of the glass sample. For Rhodamine 6G dye, the amount of uptake by glass is found to be significantly higher than that of conventionally used activated charcoal (0.1 mmol/g). Based on 29Si and 11B magic angle spinning nuclear magnetic resonance technique, it is confirmed that the increased concentration of Si–O− Na+ and BO4− Na+ linkages present in the glass with B2O3 to Na2O mole ratio of 0.23 is responsible for the increase in its uptake of the dye compared to the glass sample with B2O3 to Na2O mole ratio of 4.4. From fluorescence studies, incorporation of the dye molecules in the glass matrix is confirmed. The present study is quite relevant for the removal of dye molecules present in untreated aqueous solutions generated from the textile industry.

The carrier activity of 8-hydroxy quinoline (oxine) towards the facilitated transport of copper ions through chloroform bulk liquid membrane has been studied. The effects of pH of the source phase, the nature of stripping agents in the receiving phase, presence of other cations, nature of synergistic reagents on the transport were investigated. A solution of 0.1 M nitric acid (HNO 3 ) served as receiving phase for maximum transport of the metal ion. Addition of 2-amino pyridine to the membrane phase had a synergistic effect and caused a pronounced enhancement in the transport, while citric acid or glycine did not change the transport significantly. Maximum transport efficiency was observed for Cu 2+ ion when it was present in the concentration of 10 −4 M. Tolerance to the presence of Pb 2+ , Zn 2+ , Cd 2+ , Ni 2+ , Fe 2+ and Fe 3+ ions was investigated and it was found that Cu 2+ transport was not affected even in the presence of 10-fold concentration of these ions. This system was applied for the recovery of copper in electroplating industrial waste water samples.

Two series of boroaluminosilicate glasses having varying mole ratios of B 2 O 3 /Na 2 O (series 1) and B 2 O 3 /SiO 2 (series II) were prepared by conventional melt-quench method. Based on 29 Si and 11 B MAS NMR studies, it has been established that for series I glasses up to 15 mol% B 2 O 3 content, Na 2 O preferentially interacts with B 2 O 3 structural units resulting in the conversion of BO 3 to BO 4 structural units. Above 15 mol% B 2 O 3 for series I glasses and for all the investigated compositions of the series II glasses, silicon structural units are unaffected whereas boron exist in both trigonal and tetrahedral configurations. Variation of microhardness values of these glasses as a function of composition has been explained based on the change in the relative concentration of BO 4 and BO 3 structural units. These glasses in the powder form can act as efficient room temperature ion exchangers for metal ions like Cu 2+ . It is seen that the ion exchange does not affect the boron and silicon structural units as revealed by IR studies.

8‐Hydroxy quinoline was used successfully as a carrier for the transport of molybdenum across a bulk liquid membrane of chloroform. The pH of the feed solution was adjusted to 5.5. A mixture of 0.1‐M nitric acid and 0.2‐M hydrogen peroxide served as receiving phase for the maximum transport of the metal ion. Under the optimized experimental conditions, 80% of molybdenum was transported across the membrane in 5 hr and the value increased to 95% in 24 hr. Addition of 1,10 phenanthroline to the feed solution had a synergistic effect and caused a pronounced acceleration of the transport, while the effect of Dibenzo 18 crown 6 was insignificant. The transport of molybdenum was made selective by the addition of suitable masking agents to the feed solution. Most of the common interfering metal ions were masked by the addition of EDTA. The interference from tungsten was eliminated with citrate and the co‐transport of uranium was minimized by the addition of ammonium carbonate to the feed solution.

Colloidal cadmium selenide (CdSe) nanoparticles capped by a short chain thiol ligand thioglycolic acid (TGA) were prepared in aqueous medium at using sodium selenite as the selenium source. The prepared particles were efficiently transferred into organic phases through the partial ligand exchange process using 1-dodecanethiol (1-DDT). The FT-IR spectrum analysis shows the existence of the ligands on the surface of the nanoparticles in aqueous and organic phase through their characteristic modes. TEM analysis of the prepared samples reveals the size and crystalline nature of the particles. EDX analysis indicates the presence of respective elements in the resultant powdered sample. The possible mechanism of the phase transfer process was analysed. The resultant phase-transferred particles can efficiently be blended with a low band gap semiconducting polymer in a common solvent for active layer in hybrid solar cell fabrication. The results are discussed in detail.

Uranyl ion selective electrode based on 5,11,17,23,29,35-hexa- tert -butyl-37,38,39,40,41,42-hexahydroxy calix[6]arene (calixarene I) and tri- n -octyl phosphine oxide (TOPO) incorporated into a poly(vinyl chloride) (PVC) membrane has been developed. The PVC membrane containing the active ingredients was casted on the surface of a graphite electrode. The electrode showed a near Nernstian response to uranyl ion in the concentration range of 10 −1 to 10 M with an average slope of 27 mV per decade. The best performance of the electrode could be obtained by using a sensor mixture of calixarene and TOPO in the weight ratio of 1:100. The optimum pH range was between 3.2 and 4.6. Alkali and alkaline earth metal ions did not interfere with the determination of uranyl ion. There was nominal interference from Cu 2+ , Ni 2+ , Co 2+ and Al 3+ , while Fe 3+ , Th(IV), EDTA and F − interfered seriously. The interferences from these ions could be eliminated by coating the membrane surface with Nafion. Nafion coating eliminated the anionic interference while the interference from transition metal ions and thorium, could be minimized by converting them to their anionic complexes with EDTA or F − .

Transport of uranyl ion across a bulk liquid membrane using chloroform solutions of calixarenes (as carriers) has been studied. Various factors that affect the transport have been optimised in order to obtain maximum transport. It has been observed that the use of tri-n-octyl phosphine oxide (TOPO) as a synergistic reagent showed a marked enhancement of transport of uranyl ion. Crown ether 18 Crown 6 (18C6) also exhibited synergistic behaviour when used in combination with calixarenes. The use of these synergistic reagents resulted in high transport of uranyl ion with 0.1 M nitric acid as the receiving solution. The interference from different transition metal ions was found to be negligible. The serious interference from Th(IV) could be minimised by using EDTA as masking agent. A possible application of this carrier system and transport process to the pre concentration and recovery of uranium from seawater has also been examined.

Removal of various toxic species from aqueous streams is of great importance. Sorption is one of the important remediation procedures as it involves the use of cheap and easily available materials. Also the advantage of regeneration of the sorbent involves the possibility of using novel sorbents. Nanosorbents are very important as the removal is based on the surface phenomena and this is greatly affected by surface charge and area. Functionalization has been very important to bring about the removal of metal ions with greater selectivity., {"references":["F.W. Pontius, J. Am. Water Works Assoc., 1996, 88:22-27, 30-33.","J. Y. Choi, D. S. Kim, J. Y. Lim, J. Environ. Sci. Health A Tox. Hazard. Subst. Environ. Eng. 2006, 41, 1155-1172.","S. Pacheco, R. Rodriguez, J. Sol-Gel Sci. Technol. 2001, 20, 263–273.","F. M. Koehler, M. Rossier, M. Waelle, E. K. Athanassiou, L. K. Limbach, R. N. Grass, D. Günther, W. J. Stark, Chem. Commun. (Cambridge), 2009, 4862–4864.","S. Singh, K. C. Barick, D. Bahadur, J. Mater. Chem. A. 2013, 1, 3325 -3333.","B. R. White, B. T. Stackhouse, J. A. Holcombe, J. Hazard. Mater. 2009, 161, 848–853.","S. Singh, K. C. Barick, D. Bahadur, J.Hazard. Mater. 2011, 192, 1539-1547.","Jerina Majeed, Jayshree R, S. Chandramouleeswaran, O. D. Jayakumar, A. K. Tyagi , RSC Adv. 2013, 3, 3365-3373."]}