Measurement of natural radionuclides in bricks and brick-making clays from Cuddalore district,Tamilnadu,India

In India,bricks as building materials are mainly prepared by clay using the deposited sediments of rivers,and the radionuclide contents in bricks and brick-making clays should vary with origin and geological condition.In this paper,the radionuclide contents of these materials from river bank areas of Cuddalore district,Tamilnadu India are measured by gamma ray spectrometer using NaI(Tl) detector,and compared with those of other countries.The radiation hazard indices,which are evaluated by radium-equivalent(Raeq) activity,are lower than that of NEA-OECD.

Spatiotemporal binary interaction and designer quasi-particle condensates

We introduce a new integrable model to investigate the dynamics of two component quasi-particle condensates with spatiotemporal interaction strengths. We derive the associated Lax pair of the coupled Gross-Pitaevskii （GP） equation and construct matter wave solitons, We show that the spatiotemporal binary interaction strengths not only facilitate the stabilization of the condensates, but also enables one to fabricate condensates with desirable densities, geometries, and properties, leading to the so-called ＂designer quasi-particle condensates＂.

Medicinal Plant Using Ground State Stabilization of Natural Antioxidant Curcumin by Keto-Enol Tautomerisation

Curcumin is a medicinal agent that exhibits anti-cancer properties and bioactive pigment in Turmeric has a huge thera-peutic value.It has a keto-enol moiety that gives rise to many of its chemical properties.A recent study has shown thatketo-enol tautomerisation at this moiety is implicated the effect of curcumin.The tautomerisation of curcumin in methanol.acetone and acetonitrile are used in nuclear magnetic resonance(^(1)H,^(13)C)spectroscopy.It was characterized using UV,IRand Raman spectral values.The molecular electrostatic potential surface of the Curcumin has been visualized in elec-tropositive potential in the region of the CH^(3+) group and most electronegative potential in the two oxygen atom has verystrong binding group.In the following,the modality of structural and thermo dynamical parameters,electrophilicity(ω).chemical potential(μ),chemical hardness(η) and electronic charge transfer confirms the local reactivity.The rate constantof tautomerisation of curcumin shows strong temperature dependence.Molecular electrostatic potential and Temperature dependence of various thermodynamic properties like(C^(0)_(p,m),S^(0)_(m),and H^(0)_(m))is increase with increase in temperature formonomer and dimer of various electrical fields.

Type Inversion and Certain Physical Properties of Spray Pyrolysed SnO_2:Al Films for Novel Transparent Electronics Applications

Aluminium doped tin oxide films have been deposited onto glass substrates by using a simplified and low cost spray pyrolysis technique. The AI doping level varies between 0 and 30 at.% in the step of 5 at.%. The resistivity （p） is the minimum （0.38 Ω cm） for 20 at.% of AI doping. The possible mechanism behind the phenomenal zig-zag variation in resistivity with respect to AI doping is discussed in detail. The nature of conductivity changes from n-type to p-type when the AI doping level is 10 at.%. The results show that 20 at.% is the optimum doping level for good quality p-type SnO2：AI films suitable for transparent electronic devices.

Experimental charge density distribution and its correlation to structural and optical properties of Sm^3＋ doped Nd2O3 nanophosphors

Pure and Smdoped NdOnanophosphors were synthesized using modified Pechini method. The phase formation with symmetry of the sample is confirmed by the Rietveld refinement of the powder Xray diffraction(PXRD) data. The surface morphology and the crystallite size were examined using scanning electron microscopy(SEM) and transmission electron microscopy(TEM) and the results confirmed that the synthesized particles are in nanosize. The energy-dispersive X-ray(EDX) analysis was done to confirm the purity of the sample. The optical properties of the sample were studied using ultraviolet-visible range(UV-Vis) spectroscopic analysis and photoluminescence studies. The calculated band gap of the synthesized NdOwas found to be higher than that of bulk NdO. The photoluminescence(PL) of the prepared samples reveals that doping with Sm3+ ion has influenced the optical properties. Quantitative investigation on charge density distribution was done by analysing the 3-dimensional and 2-dimensional charge density maps drawn along the bonding directions. The maximum entropy method(MEM)/Rietveld analysis was used for the first time to analyse the charge density in the chosen system. Charge density arrangement in the unit cell is correlated to the analysed photoluminescent(PL) properties. The spectral behaviour of the samples has been explained through charge ordering which are verified using experimental data obtained. The studies on these materials have shown that these nanophosphors will provide promising application for near-ultraviolet lightemitting diodes(n-UV-LEDs).

High-temperature synthesis and electronic bonding analysis of Ca-doped LaMnO_(3) rare-earth manganites

Doped lanthanum manganites La_(1-x)Ca_(x)MnO_(3) with five different concentrations of Ca(x=0.1,0.2,0.3,0.4 and 0.5) were synthesized by high-temperature solidstate reaction method and characterized.The prepared samples were experimentally analyzed by X-ray diffraction(XRD),ultraviolet-visible spectroscopy(UV-Vis),scanning electron microscopy/energy dispersive spectroscopy(SEM/EDS) and vibrating sample magnetometer(VSM)measurements.Orthorhombic structure is confirmed for this compound from powder X-ray diffraction data.The XRD data confirm the shrinkage in the unit cell of synthesized samples for increasing calcium concentration.The UV-Visible analysis for the estimation of optical band gap(E_(g)) reveals that the band gap decreases with the incorporation of Ca.The synthesized samples were investigated for charge density distribution using maximum entropy method,utilizing the XRD data sets.From the charge density analysis,it is found that the bond lengths for La-O and Mn-O bonds decrease with the addition of Ca.The ionic nature between La and O atoms and covalent nature between Mn and O atoms are enhanced for 40% of calcium-doping.For 50% of Ca-doped sample,ionic nature between La and O atoms and covalent nature between Mn and O atoms decrease.All the prepared samples exhibit ferromagnetism at 20 K and paramagnetism at 300 K.

Enhancing the Antibacterial Efficiency of ZnO Nanopowders Synthesized by Combustion Method Through Ag+Fe Co-doping

（Ag ＋ Fe）-doped ZnO nanopowders have been synthesized using combustion method. Ag doping level was kept as 2 at.%, and Fe doping level was varied from 3 to 6 at,%, and the structural, optical, surface morphological, and antibacterial properties have been investigated. The structural studies show that ZnO/（Ag 4-Fe） nanopowders have hexagonal wurtzite structure with a preferential orientation along the （101） plane. The FE-SEM images indicate that there is a gradual decrease in the grain size with the increase in the doping level of Fe, and the TEM images are correlated well with FE-SEM images. The XPS profile clearly confirms the presence of expected elemental composition. Photolumi- nescence studies reveal the presence of extrinsic defects in the material. Antibacterial activity of Ag- and Fe-doped ZnO nanopowders against Vibrio parahaemolyticus, Vibrio Cholerae, and Staphylococcus aureus bacteria was also investigated.

Charge distribution around Ba-O and Ti-O bonds in BaTi_(1-x)Zr_(x)O_(3)through powder X-ray diffraction

Ferroelectric lead-free BaTi_(1-x)Zr_(x)O_(3)ceramic powder samples with various compositions(x=0,0.04,0.06)have been synthesized by conventional high-temperature solid-state reaction method at 1450℃for 10 h.Influences of Zr doping on the inter-atomic bonding and charge density distributions inside the lattice structure of BaTiO_(3)were analyzed through powder X-ray diffraction(XRD)and maximum entropy method.Lattice parameter and cell volume values are found to be increasing with the incorporation of Zr content.Calculated average grain sizes are found to be in the range of 23-28 nm.Maximum entropy mapping of electron density analysis reveals the reduction in ionic nature along Ba-O bond and the enhancement of covalent nature along Ti-O bond.Energy band gap values were determined from ultraviolet-visible(UV-Vis)spectra.Surface morphology and microstructures of the samples were analyzed from scanning electron microscopy(SEM)micrographs.Particles with irregular sizes were observed in all the prepared ceramics.Stoichiometry of the samples was further confirmed by energydispersive X-ray spectroscopy(EDAX).

Ceramic bodies with rock processing residues(RPR)for constructing materials

The rock processing residue(RPR)waste is used for part of the ceramic products.The present work deals with the unused waste useful for making ceramic materials and save the area and the dump space.The residues are initially analyzed with the chemical and spectroscopic method.The residues are mixed with clay of proportions 0-50 wt%in steps of 10%.The prepared specimens are characterized with Fourier transform infrared(FTIR),X ray fluorescence(XRF)for chemical,mechanical,and physiochemical properties,such as density,compressive strength,weight loss on ignition and porous nature,which are measured through the selective instrument.The thermal stability of the product was tested by firing at 950℃.This says the rock residues are useful for making ceramic and related materials with high concentrations.