Certified reference material (CRM) for trace elements in quartz matrix is required to assess the performance of analytical methods in regards to their validation, calibration and for comparability of measurements between laboratories. Due to unavailability of matrix matched CRMs in our country, National Centre for Compositional Characterization of Materials (NCCCM) of Bhabha Atomic Research Centre (BARC), Hyderabad and Council of Scientific and Industrial Research CSIR-National Physical Laboratory (NPL), New Delhi have initiated a program for the production of a CRM for the certification of critical trace elements in high purity quartz. Preparation and certification of Indian Reference Material (BND 4101.01), quartz powder with certified mass fractions of seven trace impurities was carried out jointly between NCCCM and NPL; two national laboratories of Government of India. Sampling constant (Ks) were established before carrying out the homogeneity test within and between bottles. The homogeneity test was carried out by NCCCM. The certified values were assigned after Inter Laboratory Comparison Exercise (ILCE) between reputed National Laboratories in India as per ISO-Guide 34 & 35. Analytical techniques like Inductively coupled plasma atomic emission spectrometry (ICP-AES), Flame atomic absorption spectrometry (FAAS) and Total reflection x-ray fluorescence analysis (TXRF) have been used for the characterization of property values.

A novel graphene oxide mediated microwave assisted cloud point extraction is developed in basic solution, for the extraction of ultra trace beryllium from natural water and plant waste water.

A new method for extraction and determination of trace and ultratrace impurities from edible oils via an ultrasound-assisted extraction using tetramethylammonium hydroxide (TMAH) and ethylenediaminetetraacetic acid (EDTA) has been described. Method is simple and sensitive. Extraction variables like pH, concentrations of TMAH and EDTA, ultrasonication and centrifugation times were all optimised for analyzes using engine-oil. Under optimised conditions, extraction of spiked analyzes from all the edible oils into aqueous-medium were investigated and found to be quantitative (89-101%). Using this method, concentrations of impurities in edible-oils were determined by graphite furnace atomic absorption spectrometer (GFAAS) using standard-addition calibration method and validated with microwave-digestion method. The method was successfully applied to edible oils extracted from various seeds such as mustard oil, sun flower oil, sesame oil, ground nut oil, coconut oil, rice bran oil and corn oil containing ultratrace impurities. Accuracy of developed method for edible-oils was checked with corresponding results obtained by microwave digestion method.

A wet chemical method is reported to characterize ultrapure germanium (Ge) of 9N (99.9999999%) purity. In this method, matrix germanium is separated from all its impurities with a matrix volatilization procedure. Chlorine gas is generated in situ and reacts with Ge solid material directly at the temperature of 230 +/- 5 degrees C and separates the Ge matrix as volatile GeCl4 from all its impurities. Further modifications were done to the matrix volatilization setup earlier used for 8N pure Ge to further control the contamination of the atmospheric gases to the 9N pure Ge sample during the different stages of matrix volatilization. After modifications, the method provides sub parts per billion and parts per trillion levels of process blanks and extremely low limits of detection. More than 60 elements were examined for their separation from the Ge matrix using the proposed method and found to be quantitatively separated. Determination of impurity concentrations was performed by inductively coupled plasma quadrupole mass spectrometer (ICP-QMS) and high resolution continuum source graphite furnace atomic absorption spectrometer (HR-CS-GFAAS). In the absence of certified reference materials for ultrapure Ge, accuracy of the present method was established by spike recovery tests. Precision of this method was between 4 to 10% for impurity concentrations from 0.28 to 0.011 ng g(-1). Limits of detection (LOD) were found between 4.6-0.005 ng mL(-1) or 1.4-0.002 ng g(-1) for the target analytes. The wet chemical method was found to be useful for the characterization of ultrapure Ge material of 9N purity.

Food Safety and Standards Authority of India has set maximum permissible level of lead in noodle at 2.5 mg/kg. The standardized lead measurement is of high priority in food matrix to obtain closer comparability of results obtained using routine measurement procedures. For this purpose, certified reference material (CRM) for lead in noodle matrix is required to assess analytical methods performance with respect to their validation, calibration and of comparability of measurements between laboratories. Considering the unavailability of matrix-matched reference materials, National Centre for Compositional Characterization of Materials (BARC-NCCCM) has initiated a program for the production of a noodle CRM for the certification of lead mass fraction. Various parameters for homogeneous spiking were optimized for the production of 2.35kg of homogeneous noodle matrix. Parameters for sample digestion and minimum sample intake for analytical homogeneity (H-E) were established before carrying out the homogeneity test between and within bottles. Homogeneity assessment and stability tests were carried out according to the ISO Guide 34 and 35. The certified value was assigned after inter-laboratory comparison exercise where eight national laboratories of repute from both government and private sector participated.

A novel sequential/simultaneous extraction procedure was developed for determining Tl(I) and Tl(III) and total Tl in coal mine effluents. In this method, the selective formation of anionic species of Tl(I) and Tl(III) with HCl and diethylenetriamine pentaaceticacid (DTPA), respectively, were introduced in a mixed micelle cloud point extraction. An Aliquat-336 and Triton X-114 aggregates acted as ion-pair and extracting agents. In sequential extraction, the hydrophilic Tl(III)-DTPA(2?), first reacted with cationic aggregate through electrostatic interaction and extracted into a small aggregate rich phase and leaves the cationic Tl(I) in supernatant. This was subjected to a similar extraction after converting Tl(I) into TlCl32? on addition of HCl. In simultaneous extraction, total Tl was extracted by adapting a similar extraction, adding HCl and DTPA, avoiding the chelating and oxidation/reducing agents. Parameters affecting the process are optimised using GFAAS. Under the optimised conditions, the detection limit and pre-concentration factor were 15 pg mL(?1) and 25(,) respectively for both sequential and simultaneous extractions. The recoveries of Tl(III) and Tl(I) were between 85% and 104% in the range of 0.5 to 3 ng mL(?1). A certified reference material, NIST 1643c, was used to verify the accuracy of the procedure. The method was applied to natural waters and coal effluents.

BACKGROUND:Surveillance of post-kala-azar dermal leishmaniasis (PKDL) is critical to the elimination of visceral leishmaniasis (VL). In this study we assessed the feasibility of using trained field workers for detecting suspected PKDL cases.METHODS:A cross-sectional study using a multistage sampling technique was conducted in the Araria district of Bihar. Trained field workers were utilized for identification of suspected PKDL case.RESULTS:We investigated 57 099 individuals from 11 300 households. The trained field workers were useful in identifying 107 (18%) probable PKDL cases. The calculated PKDL prevalences were 18.7/10 000 and 9.7/10 000 for probable and confirmed PKDL cases, respectively. The median duration of onset of PKDL was 23 months (interquartile range 16.5-56.5). The younger age group developed PKDL significantly more often compared with the older age group (p=0.007). Of the 107 patients, 25 (55.5%) were positive by microscopy of slit skin smear and 42 (93.3%) by polymerase chain reaction. Of 45 patients, 33 (73%) PKDL cases were cured after full treatment. The risk of not being cured with incomplete treatment was three times higher than with complete treatment (relative risk 3.12 [95% confidence interval 1.23 to 8.67], p=0.004).CONCLUSIONS:We conclude that the prevalence of PKDL is high and the use of trained field workers may be feasible to actively detect PKDL cases in VL-endemic areas of Bihar, India.

In the present study, a green chemistry based cloud point extraction (CPE) method has been developed for the in situ synthesis and preconcentration of cetylpyridinium complexed hexaiodo platinum nanoparticles (Pt-I NP) from the leachate of spent automobile catalytic converter using potassium iodide (KI) and assisted by a combination of cationic and non-ionic surfactants; cetylpyridinium bromide (CPB) and Triton X-114, respectively. The process parameters such as concentrations of hydrochloric acid, platinum, KI, sodium chloride, CPB, Triton X-114; incubation temperature and complexation time on CPE were optimized. The synthesized nanoparticles were characterized by UV-visible spectroscopy (UV-vis), transmission electron microscopy (TEM), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS) and zeta potential techniques. The formation of Pt-I NP was followed with UV-vis. The XRD pattern established the tetragonal crystal structure of the produced nanoparticles. The nanoparticles were spherical in shape and the particle size obtained with TEM was about 5.6 nm. Further, the preconcentrated nanoparticles were quantified by continuum source electro-thermal atomic absorption spectrometry (ET-AAS) and a preconcentration factor of 25 was obtained for a reaction volume of 25 mL. The accuracy of the developed method was confirmed by analyzing the certified reference materials such as CCRMP PTM-1a (copper-nickel sulphide matte) and CCRMP PTC-1a (copper-nickel sulphide concentrate). The current CPE protocol demonstrates advantages such as simultaneous synthesis and preconcentration; synthesis at micromolar concentration from metal scrap, higher nanoparticle recovery; biodegradability and biocompatibility of the employed surfactants and dual solubility of the synthesized Pt-I NP. Thus, the developed method can be applied for the separation, large scale synthesis and preconcentration of Pt-I NP from various environmental and industrial wastes, in a single pot. (C) 2019 The Author(s). Published by Elsevier B.V. on behalf of King Saud University.

In this work, a new surfactant assisted dispersive liquid-liquid microextraction procedure is developed for removal/recovery of potentially harmful trace and ultra-trace levels of beryllium from industrial effluents. An anionic hydrophobic double tailed surfactant, dioctyl sodium sulfosuccinate (AOT) is used as the dispersing solvent which disperses uniformly in aqueous as well as in extracting solution by forming vesicle aggregates. These vesicles entrap beryllium in its cavity in the presence of salicylic acid. Chloroform is used as extracting agent for the pre-concentration of the vesicles carrying beryllium salicylate from bulk aqueous phase into a small chloroform phase at room temperature providing an energy efficient extraction process. The recoveries are in the range 88%-99% at 0.05-1,000 ng mL(-1) beryllium with relative standard deviation of 1%-10%. Several factors influencing the recovery were optimized for providing better recoveries. The formation of vesicles has been conformed in the transmission electron microscope analysis. Under the optimized conditions, the pre-concentration factor is 25. The accuracy of the procedure is verified by analyzing NIST standard reference materials such as 1640, 1640a and 1643e using electrothermal atomic absorption spectrometry. The procedure has been utilized for the recovery of beryllium from effluent samples collected from beryllium processing plant and also been applied to natural water samples.

A new synergetic salt- and add-induced ligandless mixed micelle cloud point extraction procedure was developed for the simultaneous separation and preconcentration of Cd, Hg, Bi, and 11 from petrochemical effluents and groundwater samples. The cationic mixed micelles are formed by the micelle-micelle interaction of cationic cetylpyridinium ammonium bromide (CPAB) and nonionic Triton (R) X-114 micelles, which act as an ion pair and extracting agent. Due to the synergetic effect of potassium iodide and sulfuric add, the hydrophilic anionic Cd, Hg, Bi, and Tl iodide species are formed. These also induce the clouding phenomenon in cationic mixed micelles. The strong electrostatic interaction between the mixed micelles head groups and the anionic iodide species form the hydrophobic ion pairs which are separated from the bulk aqueous phase into a small mixed micelle-rich phase, thus avoiding] the addition of an external chelat ing agent. Under the optimized conditions, a pre-concentration factor of nearly 20 times was obtained for all of the elements. The limits of detection obtained were 0.0005, 0.2, 0.04, and 0.05 ng mL(-1) for Cd, Hg, Bi, and Tl, respectively. The recoveries were in the range of 93 102% at 0.1 to 10 ng with a relative standard deviation of 2-10%. The accuracy of the method was validated by analysis of certified reference materials BCR 714 Initial Influent, BCR 715 Industrial Effluent, BCR 610 Groundwater, and MIST 1643e, 1643f, and 1642b Trace Elements in Water. The method was also applied to real samples of petrochemical effluents and groundwater collected locally. A continuum source electrothermal atomic absorption spectrometer (CS-ETAAS) was used for the determination of the elements.

The present study involves the estimation of ring tensile properties of Indian Pressurised Heavy Water Reactor (IPHWR) fuel cladding made of Zircaloy-4, subjected to experiments under a simulated loss-of-coolant- accident (LOCA)condition. Isothermal steam oxidation experiments were conducted on clad tube specimens at temperatures ranging from 900 to 1200 degrees C at an interval of 50 degrees C for different soaking periods with subsequent quenching in water at ambient temperature. The specimens, which survived quenching, were then subjected to ambient temperature ring tension test (RTT). The microstructure was correlated with the mechanical properties. The yield strength (YS) and ultimate tensile strength (UTS) increased initially with rise in oxidation temperature and time duration but then decreased with further increase in oxidation. Ductility is adversely affected with rising oxidation temperature and longer holding time. A higher fraction of load bearing phase and lower oxygen content in it ensures higher residual ductility. Cladding shows almost zero ductility behavior in RIT when load bearing phase fraction is less than 0.72 and its average oxygen concentration is greater than 0.58 wt%. (C) 2017 Elsevier B.V. All rights reserved.

Hussain Sagar is a man-made lake originally designed for drinking water purpose that receives domestic sewage and industrial effluents through drainage canals due to rapid residential and industrial growth. Also, every year thousands of idols are immersed into the lake during festivals. In this context, a comprehensive study was initiated for monitoring the lake water quality. Various physico-chemical parameters such as temperature, pH, EC, TDS, COD and chlorophyll a were analyzed using APHA standard methods Water was also monitored for heterotrophic bacteria, total coliforms, Escherichia coli and antibiotic resistant bacteria. The average values for heterotrophs were found to be 8.6×104 and 2.8×104CFU/mL before and after idol immersion, respectively. While the average values for total coliforms and E. coli were 5×104 and 5×102; 1.2×104 and 7.2×101CFU/mL, for the respective sampling periods. The mean values for ampicillin and gentamicin resistant bacteria were 5.9×103 and 6.9×102; and 2.2×103 and 5.4×102CFU/mL, respectively. It was found that TDS, COD and chlorophyll a values were decreased after idol immersion due to extensive cleaning. The statistical results showed no correlation between faecal bacteria and physico-chemical parameters and one way-ANOVA indicated statistically significant differences between the mean values of different sampling locations, with respect to COD and E. coli at 95% confidence. However, enormous load of coliforms and E. coli indicated severe contamination of the lake with domestic sewage and human excreta. Thus, the water is not suitable for human consumption/drinking purpose. Notably, incidence of antibiotic resistant bacteria in lake water is a potential threat to both public health and the environment. Thus, regular monitoring and applying appropriate corrective actions are needed to improve the water quality.

A simple multielemental mixed micelle cloud point extraction procedure has been developed for the simultaneous separation and preconcentration of toxic trace analytes from natural and wastewater samples prior to their determination by electrothermal atomic absorption spectrometry. The analytes Cr, Be, Pb, Cd, Tl, and Hg were converted simultaneously, as hydrophilic anionic iodide species formed with KI in the presence of HCl. The method is based on the formation of extractable ion associates of anionic iodide species with solubilizing cationic and hydrophobic sites of mixed micelles. The mixed micelles are formed by cationic, Aliquat-336 (N-methyl-N,N,N-trioctylammonium chloride) and nonionic, Triton X-114. The ion associates formed are preconcentrated from bulk aqueous phase into a small mixed micelle-rich phase, avoiding the addition of an external chelating agent. The parameters affecting the process are evaluated and optimized. The recoveries of anaytes are in the range of 86-102% at 0.1-10gL(-1). The accuracy of the procedure has been verified by using certified reference materials, such as National Institute of Standards and Technology (NIST) 1640a natural water, Community Bureau of Reference (BCR)-713 final effluent, and BCR-715 industrial effluent and being applied to industrial wastewater.

This study investigates the failure of embrittled Zircaloy-4 cladding in a simulated loss of coolant accident condition and correlates it with the evolved stratified microstructure. Isothermal steam oxidation of Zircaloy-4 cladding at high temperatures (900-1200 degrees C) with soaking periods in the range 60-900 s followed by water quenching was carried out. The combined oxide + oxygen stabilized alpha-Zr layer thickness and the fraction of the load bearing phase (recrystallised alpha-Zr grains + prior beta-Zr or only prior beta-Zr) of clad tube specimens were correlated with the %ECR calculated using Baker-Just equation. Average oxygen concentration of the load bearing phase corresponding to different oxidation conditions was calculated from the average microhardness using an empirical correlation. The results of these experiments are presented in this paper. Thermal shock sustainability of the clad was correlated with the % ECR, combined oxide+alpha-Zr(O) layer thickness, fraction of the load bearing phase and its average oxygen concentration. (C) 2016 Elsevier B.V. All rights reserved.

Micelle and mixed-micelle sequential and simultaneous speciation of Cr(iii), Cr(vi) and Cr (total) can be performed for microlitre volumes on site.

Modified matrix volatilization (MV) method has been described to characterize high purity germanium material of 7 N (99.99999%) purity. Transport of both, the chlorine gas generated in-situ in this method and the argon gas (carrier) is fine controlled by means of a mass flow controller. This enabled both uniform reaction of chlorine gas with the germanium matrix and smooth removal of germanium matrix as its chloride. This resulted in improvement in the reproducibility of the analytical results. The use of quartz reaction vessel has lead to the reduction in the process blank levels. The combined effect of these modifications in the MV setup has resulted in very consistent and low process blanks and hence improved detection limits of this method. Applicability of the method has been expanded to rare earth elements and other elements after examining their recoveries. The quantification is done by using inductively coupled plasma quadrupole mass spectrometer (ICP-QMS) and continuum source graphite furnace atomic absorption spectrometry (CS-GFAAS). In the absence of certified reference materials for high pure germanium, the accuracy of the method is established by spike recovery tests. The precision of the method has been found to vary from 1 to 30% for concentrations between 1 and 30 ng g(-1). The limits of detection (LOD) for the target analytes are found to be between 18 and 0.033 ng g(-1).

A new ion pair-based surfactant-assisted dispersive liquid liquid microextraction (IP-SA-DLLME) procedure was developed for the separation and pre-concentration of ultratrace levels of beryllium from effluents and natural water samples. A cetylpyridinium ammonium bromide (CPAB) cationic surfactant was used as both ion pairing and dispersing solvent. The method is based on the formation of extractable hydrophobic ion pair complexes of an anionic specie of beryllium-oxalate with the cationic head group of CPAB dispersive aggregates in the presence of oxalic acid. Chloroform was used as an extracting solvent for the pre-concentration of the formed extractable ion pair from a bulk aqueous phase into a small chloroform phase at room temperature. This provides an energy-efficient extraction process and avoids the addition of an external chelating agent. The recoveries were in the range of 92-98% at 50-250 pg mL(-1) Be, which would be impossible to achieve with conventional dispersive liquid-liquid microextraction. Several factors influencing the recovery were investigated and optimized for providing better recoveries. Under the optimized conditions, the pre-concentration factor was 25 and the limit of detection was 1 pg mL(-1). The accuracy of the procedure was verified by ETAAS analysis of certified reference materials. The procedure was applied to effluent and natural water samples.

An improved matrix separation method has been described to characterize ultrapure germanium of 8N (99.999999%) purity. In this method, temperature of the reaction vessel in which in-situ generated chlorine gas reacts with germanium solid material directly is optimized to quantitatively remove Ge matrix from all its impurities. Optimized reaction temperature has been found to be 230±5 °C. Recovery studies on more than 60 elements have been carried out at the optimized temperature. Recoveries of all the analytes except As, Se, Sn, Hg, Tl are found to be quantitative. The method has been examined for various amounts of Ge material and found to be suitable even for 10 g of Ge sample and provides low parts per billion and trillion levels of process blanks. Determination of concentrations of impurities has been done by inductively coupled plasma quadrupole mass spectrometer (ICP-QMS) and high resolution continuum source graphite furnace atomic absorption spectrometer (HR-CS-GFAAS). In the absence of certified reference materials for ultrapure germanium, accuracy of the proposed method is established by spike recovery tests. Precision of this method is found to vary from 7% to 50% for concentrations between 4 and 0.004 ng g−1. Limits of detection (LOD) for the target analytes are found to be between 6 and 0.011 ng mL−1 or 1.8–0.003 ng g−1 for the proposed procedure. The method has been successfully applied for that characterization of ultrapure germanium material of 8N purity.