Effect of tri-n-butyl phosphate on physical properties of dodecane–nitric acid system

Extraction power of solvent depends upon the physical properties of the system. Tri-n-butyl phosphate (TBP) in dodecane is a versatile solvent used in the nuclear fuel reprocessing like PUREX process. The study of physical properties like density, viscosity, interfacial tension and solubility for TBP–nitric acid–dodecane system will be helpful in carrying out different extraction studies during PUREX process. Thus, physical properties like density, viscosity, interfacial tension and solubility have been measured for TBP–nitric acid–dodecane system using pycnometer, viscometer, pendant drop method and high performance liquid chromatography respectively. It has been observed that density and viscosity increases but interfacial tension and solubility decreases with the concentration of TBP in dodecane–nitric acid system. Physical properties of 30 % TBP–nitric acid–dodecane system have also been studied in detail. All these studies will also be useful in stripping out dissolved TBP from the nuclear waste.     

Adaptive optics wide-field microscopy using direct wavefront sensing

We report a technique for measuring and correcting the wavefront aberrations introduced by a biological sample using a Shack-Hartmann wavefront sensor, a fluorescent reference source, and a deformable mirror. The reference source and sample fluorescence are at different wavelengths to separate wavefront measurement and sample imaging. The measurement and correction at one wavelength improves the resolving power at a different wavelength, enabling the structure of the sample to be resolved.     

Variable temperature Mössbauer spectroscopic studies of oxo-centered trinuclear mixed-valence iron succinate, mesaconate and isophthalate complexes

Three new oxo-centered trinuclear mixed-valence iron complexes, iron succinate, iron mesaconate and iron isophthalate have been prepared. Temperature dependent valence delocalization processes were observed for all the complexes on variable temperature Mössbauer spectroscopic studies. Two clear quadrupole split doublets attributed to high-spin Fe(III) and high-spin Fe(II) states were existed for the complexes at liquid nitrogen temperature. At room temperature a nearly averaged singlet peak was observed for mesaconate complex and averaged doublet peaks were observed for succinate and isophthalate complexes with IS values 0.68 and 0.68 mms^?1 and QS values 0.44 and 0.48 mms^?1 respectively.     

Theoretical investigation on first-principles electronic and thermal properties of some CdRE intermetallics

Ab initio calculation on B2-cadmium rare earth (RE), CdRE (RE=La, Ce and Pr) intermetallics has been performed at T=0 K with respect to their structural, electronic and thermal properties. The structural and electronic properties are derived using self-consistent tight binding linear muffin tin orbital method at ambient and at high pressure. Other properties like lattice parameter, bulk modulus, density of states, electronic specific heat coefficient, cohesive energy, heat of formation, Debye temperature and Grüneisen constant for CdRE are also estimated. The RE-f effect can be seen in CdPr in terms of variation in the density of states and opens a possibility of structural instability. A pressure induced variation of Debye temperature is also presented for three cadmium rare earth intermetallics.     

Highly Conductive,Scalable, and Machine Washable Graphene‐Based E‐Textiles for Multifunctional Wearable Electronic Applications

Graphene‐based textiles show promise for next‐generation wearable electronic applications due to their advantages over metal‐based technologies. However, current reduced graphene oxide (rGO)‐based electronic textiles (e‐textiles) suffer from poor electrical conductivity and higher power consumption. Here, highly conductive, ultraflexible, and machine washable graphene‐based wearable e‐textiles are reported. A simple and scalable pad?dry?cure method with subsequent roller compression and a fine encapsulation of graphene flakes is used. The graphene‐based wearable e‐textiles thus produced provide lowest sheet resistance (≈11.9 Ω sq^?1) ever reported on graphene e‐textiles, and highly conductive even after 10 home laundry washing cycles. Moreover, it exhibits extremely high flexibility, bendability, and compressibility as it shows repeatable response in both forward and backward directions before and after home laundry washing cycles. The scalability and multifunctional applications of such highly conductive graphene‐based wearable e‐textiles are demonstrated as ultraflexible supercapacitor and skin‐mounted strain sensors.     

Mössbauer spectroscopic study of oxo-centered mixed-valence trinuclear iron fumarate

Oxo-centered mixed-valence trinuclear iron dicarboxylic acid complex iron fumarate [Fe₃O(O₂CCH=CHCO₂)₃(H₂O)₃]·nH₂O (n = 18-19), have been synthesized firstly. Variable temperature Mössbauer spectroscopy has been carried out to elucidate the rate of intramolecular electron transfer. It was found that the complex showed a temperature dependent mixed-valence state. At low temperature two quadrupole split doublets were observed corresponding to high spin Fe(III) and high spin Fe(II) state and a complete averaged valence state was observed at about 270 K. At temperatures between 200 and 270 K the spectra showed relaxation effect as the electron transfer rate was comparable to the Mössbauer timescale (-10^–7 s).     

Ac conduction in Al/Sb2Pb1Se7/Al devices

Metal-glass-metal (MGM) thin film devices are prepared using vacuum deposition of Sb₂Pb₁Se₇ compound. The variation of ac conductance as a function of thickness of films, temperature and frequency is studied. The observed characteristics are explained on the basis of Co-related Barrier Hopping (CBH) of bipolaron. It is shown that the theoretical curve generated using the first order approximation gives excellent fitting with the experimental curve.     

Thermoluminescence and photoluminescence study on 150 MeV proton beam irradiated K2Ca2(SO4)3:Eu phosphor

This paper investigates the thermoluminescent response of K₂Ca₂(SO₄)₃:Eu prepared by solid state diffusion method, to 150 MeV proton beams. The structural confirmation of the sample was done using the XRD technique revealing the polycrystalline nature and the formation of the compound. Samples in the form of pellets were irradiated by 150 MeV proton clinical beams with dose range of 0.1 Gy–300 Gy. Thermoluminescence glow curves of the irradiated samples were recorded and studied. It has been found that the phosphor shows a characteristic single peak at around 420 K. The TL response is linear in the range up to 200 Gy and then becomes supralinear for higher doses. Photoluminescence spectra of the sample have also been studied and reported. When the material was excited at 320 nm, single emission bands were observed at 436 nm, which can be assigned to the transitions between the lowest band of the 4f⁶5d configuration and the ground state ⁸S_7/2 of the 4f⁷ configuration of Eu²⁺ ion, confirming the incorporation of the impurity in the prepared sample. The excitation spectra of these samples at emission wavelength of 436 nm show a major band at 320 nm. The linear TL response of K₂Ca₂(SO₄)₃:Eu and low fading with good reusability, makes it a potential candidate to be used as a dosimeter for detecting the doses of proton beams for specific applications.