Daisy Joseph
Bhabha Atomic Research Centre, Physics, Faculty Member
- noneedit
- I am Phd in Physics an expert in X-ray Florescence Techniques,PIXE .I am a very sincere,honest-and sensitive scientis... moreI am Phd in Physics an expert in X-ray Florescence Techniques,PIXE .I am a very sincere,honest-and sensitive scientist but extrovert in nature.Loves nature and music. If I were not a scientist definitely I would a renowned singer.edit
Research Interests: Proton and Ideal Ethics
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Concentrations of K,Ca,Mn,Fe,Cu,Zn,Rb and Sr were determined in Indian spices namely, pepper, clove, cardamom, cinnamon and cumin by Radioisotope excited Energy Dispersive X-ray Fluoresence method. The levels of K and Ca were highest in... more
Concentrations of K,Ca,Mn,Fe,Cu,Zn,Rb and Sr were determined in Indian spices namely, pepper, clove, cardamom, cinnamon and cumin by Radioisotope excited Energy Dispersive X-ray Fluoresence method. The levels of K and Ca were highest in cinnamon and cumin and that of Mn was highest in clove and cinnamon. Rubidium and strontium were found in all spices except cinnamon. Chromium and titanium were found only in pepper. The level of toxicity and the significance of the above trace elements in the human diet are discussed.
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Zinc oxide (ZnO) and samarium (Sm) doped ZnO nanoparticles (NPs) were synthesised by solution combustion approach using citric acid as fuel. The formation of hexagonal wurtzite structure of pure and Sm doped ZnO powder was prepared and... more
Zinc oxide (ZnO) and samarium (Sm) doped ZnO nanoparticles (NPs) were synthesised by solution combustion approach using citric acid as fuel. The formation of hexagonal wurtzite structure of pure and Sm doped ZnO powder was prepared and confirmed by x-ray diffraction (XRD). The structure formation, morphological and elemental analysis of pure and Sm doped ZnO powder were analysed using XRD, Raman spectra, scanning electron microscopy (SEM) and xray fluorescence spectroscopy (XRF). The results indicated that the trivalent Sm ions were successfully doped in to the lattice of ZnO matrix. The XRD images showed that both ZnO and Sm doped ZnO NPs are highly crystalline, having hexagonal wurtzite structure.
Curcumin is known as a blood purifier in Ayurveda which has been recently ascribed to its chelating ability with metal, hence reducing the deposition of metal in the body. Curcumin can exhibit keto-enol tautomerism and in the synthesized... more
Curcumin is known as a blood purifier in Ayurveda which has been recently ascribed to its chelating ability with metal, hence reducing the deposition of metal in the body. Curcumin can exhibit keto-enol tautomerism and in the synthesized 1:1 metal complexes, the enolate ion chelate to the metal. The antioxidant activity of the synthesized metal complexes of curcumin was slightly less than the parent curcumin-I. Curcumin in the complexed state retains its antioxidant behavior, consequently establishing importance of phenolic group in deciding its antioxidant activity. The study reveals that the flexibility at the diketo moiety is not a requisite for the radical formation and sufficient scavenging of DPPH occur by phenoxide ion formation.
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Green and black tea samples available in Indian markets were analyzed for their elemental composition using Hand held X-ray Fluorescence spectrometer. Twenty eight elements were analyzed in the tea leaves. Macronutrients detected in major... more
Green and black tea samples available in Indian markets were analyzed for their elemental composition using Hand held X-ray Fluorescence spectrometer. Twenty eight elements were analyzed in the tea leaves. Macronutrients detected in major proportions were K and Ca, while Zn, Fe, Cu, Mn, and Mg were the micronutrients detected in all the samples. Si, P and S were the nonmetals detected in the tea leaves. The samples also showed presence of rare earth metals like Ag, Sr, Rb, Nb and Mo.
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The Folded Tandem Ion Accelerator (FOTIA) at Van De Graaff was used to study PIXE (Particle-induced X-ray Emission) using protons of energy 3-5 MeV. It has been used for a variety of applications from studying intensity ratios, biological... more
The Folded Tandem Ion Accelerator (FOTIA) at Van De Graaff was used to study PIXE (Particle-induced X-ray Emission) using protons of energy 3-5 MeV. It has been used for a variety of applications from studying intensity ratios, biological samples (blood), rare earth, materials (gold standards), geological samples (gemstones) pottery samples and forensic samples (ink). This article attempts to elucidate the preparation methods of the samples, the detectors used, the analysis and the findings therein for different applications.
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Coercive fields and X-Ray intensity ratios of the K-series lines of Ni films in the thickness range of 5-2000 nm deposited onto Si (111) substrate have been studied. The Coercive field is observed to increase with thickness and follows... more
Coercive fields and X-Ray intensity ratios of the K-series lines of Ni films in the thickness range of 5-2000 nm deposited onto Si (111) substrate have been studied. The Coercive field is observed to increase with thickness and follows power law for the thickness range ≥ 50 nm. For lower thickness, there is a deviation from power law. A correlated change is also observed in the Kβ/Kα X-ray intensity ratios.
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Application of energy dispersive X-ray fluorescence (EDXRF) and proton induced X-ray emission (PIXE) methods has been demonstrated for determining the elemental composition of thin film superconducting materials. The results of analysis... more
Application of energy dispersive X-ray fluorescence (EDXRF) and proton induced X-ray emission (PIXE) methods has been demonstrated for determining the elemental composition of thin film superconducting materials. The results of analysis carried out by EDXRF method have been compared with those obtained by PIXE method. Thin films of YBa2Cu3O7 superconducting material were deposited on various substrates such as thin mylar
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A Peltier cooled X-ray detector of Bruker Baltic make was tested and applied for studying pottery samples using Cd109 and Am241 radios isotope sources. The characteristics of Si(Li) Peltier-cooled detectors are close to those of detectors... more
A Peltier cooled X-ray detector of Bruker Baltic make was tested and applied for studying pottery samples using Cd109 and Am241 radios isotope sources. The characteristics of Si(Li) Peltier-cooled detectors are close to those of detectors cooled with the liquid nitrogen and remain the most preferred type of detectors for the tasks of X-ray fluorescence analysis. One of the conditions to provide low detection limits for Xray fluorescence (XRF) analysis equipment is high energy resolution of the detector applied for the detection of the characteristic radiation. Semiconductor detectors offer the best energy resolution, but often at the expense of deep cooling with liquid nitrogen LN2. In recent years, there has been significant progress in the development of semiconductor detectors without the need for deep cooling. The operating temperature of these detectors could be maintained by thermoelectric Peltier coolers. The characteristics of semiconductor x-ray detectors with Peltier coole...
Mn, Cr and Cu K X-ray absorption edges were measured in various compounds containing Mn in Mn, Mn and Mn oxidation states, Cr in Cr and Cr oxidation state and Cu in 2+ states in different compounds. Few compounds are having tetrahedral... more
Mn, Cr and Cu K X-ray absorption edges were measured in various compounds containing Mn in Mn, Mn and Mn oxidation states, Cr in Cr and Cr oxidation state and Cu in 2+ states in different compounds. Few compounds are having tetrahedral coordination in the 1 shell surrounding the cation while others are having octahedral coordination. The measurements have been carried out at the energy dispersive EXAFS beamline at INDUS-2 Synchrotron radiation source at RRCAT, Indore. Energy shifts of ~ 8-16 eV were observed for Mn K edge in the Mn-compounds while a shift of 13-20 eV were observed for Cr K edge in Cr-compounds compared to their values in elemental Mn and Cr respectively. Cu showed an energy shift of 4-7 ev compared to the elemental Cu. The different chemical shifts observed for the compounds having the same oxidation state of the cation but different anions or ligands show the effect of different chemical environments surrounding the cations in determining their X-ray absorption edg...
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Nanotechnology opens a new opportunity for the food industry and food products to use new management systems has capable of treated with any risks associated with nanofoods as well as the use of nanotechnology at food industry.... more
Nanotechnology opens a new opportunity for the food industry and food products to use new management systems has capable of treated with any risks associated with nanofoods as well as the use of nanotechnology at food industry. Nanomaterials have a wide surface area per each mass unit, they are expected to be more biologically active than larger-sized particles of the same chemical composition, which offer numerous perspectives for functional food applications [1]
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A chemically modified electrode was developed for determination of metal ions (Cd, Pb, Zn, Co, Hg). The modifier used for the study was Curcumin. Curcumin acts as a complexing agent at the surface of the electrode for preconcentration of... more
A chemically modified electrode was developed for determination of metal ions (Cd, Pb, Zn, Co, Hg). The modifier used for the study was Curcumin. Curcumin acts as a complexing agent at the surface of the electrode for preconcentration of metal ions from electrolyte to electrode surface and stripped back to electrolyte during analysis. EDXRF was used to analyze these electrodes and it was concluded that the PCR modified electrode favored effective chelation for lead and mercury.A chemically modified electrode was developed for determination of metal ions (Cd, Pb, Zn, Co, Hg). The modifier used for the study was Curcumin. Curcumin acts as a complexing agent at the surface of the electrode for preconcentration of metal ions from electrolyte to electrode surface and stripped back to electrolyte during analysis. EDXRF was used to analyze these electrodes and it was concluded that the PCR modified electrode favored effective chelation for lead and mercury.
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Rice husks are the hard protecting coverings of grains of rice. Several million tons of rice husks, which can be considered as an agricultural waste, are obtained every year. Precipitated silica is commonly used reinforcing filler in... more
Rice husks are the hard protecting coverings of grains of rice. Several million tons of rice husks, which can be considered as an agricultural waste, are obtained every year. Precipitated silica is commonly used reinforcing filler in rubber industry. The objective of the present work is to replace commercial silica commonly used in natural rubber industries with high purity rice husk- nanosilica (RHNS). Nanosilica was obtained from rice husk through a simple sol get method. The synthesized RHNS was characterized by FTIR, XRD, SEM, BET, TEM etc. From BET analysis the surface area of RHNS was found to be 252m 2 /g which is greater than that of commercial silica (CS). The particle size of RHNS was found to be 10-15 nm. The mechanical properties of natural rubber incorporated with RHNS shows better results than commercial silica.
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A novel nanoscale zero-valent iron Sargassum swartzii (nZVI-SS) biocomposite was synthesized and evaluated its ability to adsorb Crystal violet (CV) from aqueous solutions. Involvement of various functional groups of the biosorbent in... more
A novel nanoscale zero-valent iron Sargassum swartzii (nZVI-SS) biocomposite was synthesized and evaluated its ability to adsorb Crystal violet (CV) from aqueous solutions. Involvement of various functional groups of the biosorbent in preferential adsorption of cationic dye were observed using FTIR spectroscopy. Morphological changes occurring on the biocomposite materials were characterized using Scanning Electron Microscopy (SEM). Significant increase (∼90%) in the biosorption of cationic dye was observed with gradual increase in pH of the medium from 3 to 12. The effect of biosorbent concentration, initial pH, temperature, agitation rate, adsorption time and initial dye concentration was studied for the biosorption of CV using nZVI biocomposite. During the optimization study, maximum biosorption capacity was observed at pH of 8. At various initial CV concentrations (20 - 100 mg/L), attainment of batch sorption equilibrium was observed within 120 min of reaction time. Langmuir iso...
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Rice husks are the hard protecting coverings of grains of rice. Several million tons of rice husks, which can be considered as an agricultural waste, are obtained every year. Precipitated silica is commonly used reinforcing filler in... more
Rice husks are the hard protecting coverings of grains of rice. Several million tons of rice husks, which can be considered as an agricultural waste, are obtained every year. Precipitated silica is commonly used reinforcing filler in rubber industry. The objective of the present work is to replace commercial silica commonly used in natural rubber industries with high purity rice husk-nanosilica (RHNS). Nanosilica was obtained from rice husk through a simple sol get method. The synthesized RHNS was characterized by FTIR, XRD, SEM, BET, TEM etc. From BET analysis the surface area of RHNS was found to be 252m 2 /g which is greater than that of commercial silica (CS). The particle size of RHNS was found to be 10-15 nm. The mechanical properties of natural rubber incorporated with RHNS shows better results than commercial silica.
K- Shell X-ray Intensity Ratios of Fe, Ag and Te via Electron Capture Decay Employing 2π geometry S. B. Gudennavar1*, S.G. Bubbly1, Daisy Joseph2, P. V. Sreevidya1 and Linu George1 1Department of Physics, Christ University, Bangalore-560 029, INDIA 2Nuclear Physics Division, Bhabha Atomic Researc...more
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The single photon counting X-ray CCD camera spectrometer is used in laser-plasma interaction experiments as a simple tool to study the K-shell X-ray generation . Since these spectrometers require almost no alignment, they are a useful... more
The single photon counting X-ray CCD camera spectrometer is used in laser-plasma interaction experiments as a simple tool to study the K-shell X-ray generation . Since these spectrometers require almost no alignment, they are a useful tool to study the X-ray flux variations in laser-plasma interaction experiments. A CCD detector enables the spectrum of the impinging X-ray radiation to be obtained without further dispersive devices. To calibrate the CCD for x-ray spectrum measurement, Americium-241 gamma source was used to excite x-rays from different mixed metal samples (containing Ti, Cu, Fe, Zn, Cr). The experiment was setup with the CCD placed in front of the metal target. The Americium-241 source was placed behind this target foil and the X-rays generated in the target were collected by CCD. It is seen that for a better quality spectrum with good spectral resolution, only single pixel events should be considered and in cases where the incident x-ray flux is small, multiple pixel...
Using a simple method of targets of Mo and Ag being excited by a weak Cs137 γ-ray source it was possible to determine K shell X-ray intensity ratios (I Kβ /I Kα) and the total vacancy transfer probabilities (ηKL) of Moand Ag. The targets... more
Using a simple method of targets of Mo and Ag being excited by a weak Cs137 γ-ray source it was possible to determine K shell X-ray intensity ratios (I Kβ /I Kα) and the total vacancy transfer probabilities (ηKL) of Moand Ag. The targets of Mo and Ag were excited using barium K X-rays from a weak Cs137 γ-ray source. K shell X-rays were detected using Si (Li) X-ray detector coupled to 8k multichannel analyzer. The values of I Kβ to I Kα ratios and ηKL are compared with the theoretical values and experimental data of other experimentalists and the results are found to be in good agreement.
Elemental concentrations in some herbal medical products, produced by different ayurvedic pharmacies in India, were determined using Energy Dispersive X-Ray Fluorescence Spectrometry (EDXRF). All the eight products, which were studied,... more
Elemental concentrations in some herbal medical products, produced by different ayurvedic pharmacies in India, were determined using Energy Dispersive X-Ray Fluorescence Spectrometry (EDXRF). All the eight products, which were studied, contained mercury, and four out of the eight products contained arsenic in varied amounts. Daily mercury and arsenic intakes by the patients taking these products, determined from the doses prescribed by the manufacturers, exceeded the recommendations by WHO. The present work does not argue on the toxicity of heavy metals in drugs but gives information about the presence of heavy metals at levels more than the required recommendations by various health regulatory bodies. This level of As and Hg calls for caution as far as their safe intake is concerned.
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Metal monitoring is one of the major concern of biological and bio-medical research. The Proton Induced X-ray Emission (PIXE) which is a multi elemental and non-destructive technique for trace element analysis has been set up at the... more
Metal monitoring is one of the major concern of biological and bio-medical research. The Proton Induced X-ray Emission (PIXE) which is a multi elemental and non-destructive technique for trace element analysis has been set up at the Folded Tandem Ion accelerator (FOTIA) at BARC, Trombay, Mumbai, India. A few of the bioscience applications carried out at the Van de Graaff Laboratory using PIXE will be summarized in this presentation. Tea leaves obtained from the eastern region of India were analyzed by PIXE using 2.5 MeV protons. Trace elements such K , Ca , Ti , Cr , Ni , Mn , Fe , Cu , Zn , Rb and Sr were present in varying concentration in the tea leaves. The soil analysis showed Ti , Y , Zr and Nb in addition to the elements shown in the leaves. Blood samples of children exposed to vehicular traffic exhaust were analyzed for its Pb content and it was seen that the concentrations of Pb in the blood of the children were high (6.0 μg/ml). Pb poisoning of air due to vehicular exhaust...
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K shell X-rays of barium and thallium following internal conversion decay in Cs137 and Hg203, respectively, were detected using a Si(Li) X-ray detector coupled to PC-based 8k multichannel analyser employing the method suggested earlier by... more
K shell X-rays of barium and thallium following internal conversion decay in Cs137 and Hg203, respectively, were detected using a Si(Li) X-ray detector coupled to PC-based 8k multichannel analyser employing the method suggested earlier by our group. The K shell X-ray intensity ratios and vacancy transfer probabilities for thallium and barium were calculated. The obtained results are compared with theoretical, semiempirical, and others’ experimental results obtained via photoionization as well as decay processes. The effects of beta decay and internal conversion on X-ray emission probabilities are discussed.
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Oxidative stress resistant Deinococcus radiodurans surprisingly exhibited moderate sensitivity to tellurite induced oxidative stress (LD50 = 40 μM tellurite, 40 min exposure). The organism reduced 70% of 40 μM potassium tellurite within 5... more
Oxidative stress resistant Deinococcus radiodurans surprisingly exhibited moderate sensitivity to tellurite induced oxidative stress (LD50 = 40 μM tellurite, 40 min exposure). The organism reduced 70% of 40 μM potassium tellurite within 5 h. Tellurite exposure significantly modulated cellular redox status. The level of ROS and protein carbonyl contents increased while the cellular reduction potential substantially decreased following tellurite exposure. Cellular thiols levels initially increased (within 30 min) of tellurite exposure but decreased at later time points. At proteome level, tellurite resistance proteins (TerB and TerD), tellurite reducing enzymes (pyruvate dehydrogense subunits E1 and E3), ROS detoxification enzymes (superoxide dismutase and thioredoxin reductase), and protein folding chaperones (DnaK, EF-Ts, and PPIase) displayed increased abundance in tellurite-stressed cells. However, remarkably decreased levels of key metabolic enzymes (aconitase, transketolase, 3-hydroxy acyl-CoA dehydrogenase, acyl-CoA dehydrogenase, electron transfer flavoprotein alpha, and beta) involved in carbon and energy metabolism were observed upon tellurite stress. The results demonstrate that depletion of reduction potential in intensive tellurite reduction with impaired energy metabolism lead to tellurite toxicity in D. radiodurans.
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Drought-tolerant and drought-susceptible genotypes of sorghum (Sorghum bicolor L. Monech) were analyzed by the energy-dispersive X-ray fluorescence (EDXRF) technique to study the correlation of trace elements with drought-tolerance... more
Drought-tolerant and drought-susceptible genotypes of sorghum (Sorghum bicolor L. Monech) were analyzed by the energy-dispersive X-ray fluorescence (EDXRF) technique to study the correlation of trace elements with drought-tolerance capacities. Samples prepared from mature seeds, young seedlings, and old plants were analyzed using a 109Cd radioisotope source and a Si(Li) semiconductor detector of resolution 170 eV for 5.9-keV MnKalpha X-rays. Elements such as K, Fe, Cu, Zn, Rb and Sr and Y were found to be present in varying concentrations in different samples. The trace element profile studied in the seeds of 11 genotypes and in seedlings (young and old) of 4 sorghum genotypes showed considerable variation. The genotype Arfa Gadamak (AG) showed a distinct presence of a high level of Zn in its young seedling. It was observed that in most of the genotypes (seeds), K and Fe concentrations were more in the tolerant genotype as compared to the susceptible type. The concentration of Fe de...
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ABSTRACT Abstract An Indian herbomineral drug was characterized for its trace elements by radioisotope induced EDXRF .The drug contains minerals like mercury, sulfur and arsenic disulfide, along with herbs such as dhaturra, bhrami, vacha... more
ABSTRACT Abstract An Indian herbomineral drug was characterized for its trace elements by radioisotope induced EDXRF .The drug contains minerals like mercury, sulfur and arsenic disulfide, along with herbs such as dhaturra, bhrami, vacha etc.All the above ingredients were processed together in a step wise manner (6steps), Hence the motive was to expect some change in the drug molecule at every step of processing it. The 6 samples are the samples collected at every step of drug preparation. These 6 samples which are collected as intermediatary samples would be then evaluated for its role in various neuropsychological (psychosis, depression etc) disorders in experimental animals such as rats/mice. Hence it was required to find the elements/ trace elements composition, details of chemical components present in the drug samples,. It was seen that using EDXRF it was possible to determine As and Hg .The EXAFS results also showed the presence of As in their sulphide form
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... KM Niranjana 1 ,; NM Badiger 1,* ,; Daisy Joseph 2 ,; S. Kailas 2. Article first published online: 23 SEP 2010. ... Because of the long half-life of 90 Sr, the intensity of beta particles remains constant throughout the experiment.... more
... KM Niranjana 1 ,; NM Badiger 1,* ,; Daisy Joseph 2 ,; S. Kailas 2. Article first published online: 23 SEP 2010. ... Because of the long half-life of 90 Sr, the intensity of beta particles remains constant throughout the experiment. ... 5 Perrine Chaurand, Jérôme Rose, Valérie Briois, Murielle ...
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Blood lead levels of children admitted to Sion Hospital, Bombay (India), from the adjoining Dharavi slum areas have been determined by proton-induced X-ray emission (PIXE). Blood samples were collected from 36 children with suspected lead... more
Blood lead levels of children admitted to Sion Hospital, Bombay (India), from the adjoining Dharavi slum areas have been determined by proton-induced X-ray emission (PIXE). Blood samples were collected from 36 children with suspected lead poisoning and from 20 control children. The analysis showed that the lead concentration of the patients varied from 0.1 to 6.0 micrograms ml-1. In addition to lead, K, Ca, Fe, Cu, Zn, Se, Br and Rb were also detected simultaneously, of which the concentrations of Fe, Cu, Zn, Se, Rb and Pb were determined. The high blood lead levels of the children from this area may be ascribed to environmental pollution due to heavy vehicular traffic and industrial sources.
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The K shell X-ray photons of Fe, Ag, and Te following the electron capture decay of Co57, Cd109, and I125, respectively, were detected using Si(Li) detector coupled to PC-based 8k multichannel analyzer employing a simple method suggested... more
The K shell X-ray photons of Fe, Ag, and Te following the electron capture decay of Co57, Cd109, and I125, respectively, were detected using Si(Li) detector coupled to PC-based 8k multichannel analyzer employing a simple method suggested earlier by our group. The calculated K shell X-ray intensity ratios and vacancy transfer probabilities for these elements are compared with the theoretical values predicted by Scofield and with others’ experimental values obtained via photoionization. It is found that the Κβ to Κα X-ray intensity ratio of Fe is lower by 4.0%, while that of Ag and Te are greater by 7.9% and 19.1%, respectively, from the theoretical values. These deviations may be attributed to the exchange interactions occurring between the 3p–3d shell electrons as well as the recoil effect of the nucleus due to neutrino emission.
