Electronic structure near Fermi level of Pr 2 CoFeO 6 (at 300 K) was investigated by X-ray photoemission spectroscopy (XPS) technique. All three cations, i.e., Pr, Co and Fe were found to be trivalent in nature. XPS analysis also suggested the system to be insulating in nature. Moreover, Raman spectroscopy study indicated the random distribution of the B-site ions (Co/Fe) triggered by same charge states. In temperature-dependent Raman study, the relative heights of the two observed phonon modes exhibited anomalous behaviour near magnetic transition temperature T N~2 70 K, thus indicating towards interplay between spin and phonon in the system. Furthermore, clear anomalous softening was observed below T N which confirmed the existence of strong spin-phonon coupling occurring for at least two phonon modes of the system. The line width analysis of the phonon modes essentially ruled out the role of magnetostriction effect in the observed phonon anomaly. The investigation of the lattice parameter variation across T N (obtained from the temperature-dependent neutron diffraction measurements) further confirmed the existence of the spin-phonon coupling.

The magnetic spin ordering and the magnetization dynamics of a double perovskite Pr2CoFeO6 have been investigated by employing the (dc and ac) magnetization and neutron powder diffraction techniques. The study revealed that Pr2CoFeO6 adopted a B-site disordered orthorhombic structure (Pnma). Furthermore, ab initio band structure calculations suggested an insulating antiferromagnetic ground state. Magnetization measurements revealed that the system possesses a spectrum of competing magnetic phases, viz., long range canted antiferromagnetic (AFM) spin ordering (TN ∼ 269 K), Griffiths-like phase, re-entrant cluster glass (TG ∼ 34 K), and exchange bias effects. The neutron diffraction study divulged the exhibition of a long range G-type of canted AFM spin ordering. The random nonmagnetic dilution of magnetic Fe3+ (high spin) ions by Co3+ (low spin) ions due to B-site disorder essentially played a crucial role in manifesting such magnetic properties of the system.

Open tibia fractures are the most common type of all open injuries and are more prone to infection than other long bones. To control infection various surgical techniques and antibiotic therapy are used. Local delivery of antibiotics at the tissue-implant interface using Gentamicin-coated implants is one of the methods which provide mechanical stability, effectively prevent infection and promote bony union by simple one stage procedure. Materials and Methods: Thirty patients were selected with open fracture of shaft tibia, treated operatively with antibiotic coated intramedullary interlocking nail and were followed up for a minimum of six months duration. Radiological Union was assessed using RUST Score and clinical assessment results were graded as excellent, good, fair and poor. Result: In this study of 30 patients, time taken in wound healing in 15 patients is ≤5 weeks. RUST score at 6 months in 16 patients is 8. Infection found in 2 patients and 1 patient undergone non-union. 29 patients can bear weight without pain after 6 months of surgery. 16 patients have fair outcome. Conclusion:The use of the antibiotic coated nail has good clinical and radiological outcome at six months and preliminary results support the use of antibiotic coated implants as a new potential treatment option for prevention of infection in open tibia fractures.

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The changes in crystal and magnetic structure of BiFeO3 produced by partial substitution of Bi ions by Ho ions has been studied with powder X-ray diffraction, neutron powder diffraction, dielectric and magnetization techniques. The present study demonstrates that Bi1-xHoxFeO3(x = 0.05, 0.10, 0.15, & 0.2) multiferroics shows change in crystal structure at x > 0.05. The sample with x = 0.05 exhibits rhombohedral structure (space group R3c), while the other three samples (x > 0.05) exhibit mixed phase with coexisting rhombohedral (R3c) and Orthorhombic (Pnma) structure. This change in the crystal structure is attributed to the distortion of FeO6 octahedra via substitution of Ho at phase boundaries. The magnetization studies indicate that doping of Ho in pristine BiFeO3 leads to enhancement in the ferromagnetic moment. We find that doping of Ho breaks the spin cycloid phase of BiFeO3 and creates a canted G-type antiferromagnetic structure in the hexagonal phase whereas the orthorhombic phase exhibits a collinear G-type AFM structure. The canting angle increases with increase in doping with Ho, leading to an enhancement in the ferromagnetic component in magnetization. Dielectric constant (ε′) and loss factor (tanδ) are measured in frequency range 1 kHz to 7 MHz and ε′ and tanδ show dispersion behaviour at low frequencies. The significant improvement in magnetization and dielectric properties is achieved by Ho substitution which in turn enhances the potential of BiFeO3 for multiferroics applications.