Optical configuration of an N ∶ 2N reversible decoder using a LiNbO3-based Mach-Zehnder interferometer.

These days when integrated circuit (IC) designers are facing an uphill task in limiting energy/heat dissipation, reversible computing is emerging as a potential candidate with vast application in fields like nanotechnology, quantum-dot cellular automata, and low power IC. Optical reversible logics have turned up to offer high speed and low energy computations with almost no loss of input information when a certain (arithmetic or logical) operation is performed. This paper explores an optical implementation of an optimized Fredkin gate that is employed to design an $ N:2^N $ reversible decoder. The optical designs have been carried out using the electro-optic effect of a lithium niobate ($ {{\rm LiNbO}_3}$)-based Mach-Zehnder interferometer under the beam propagation method (BPM) with Optiwave's OptiBPM tool. The mathematical model of output power of these designs is also performed along with its validation in MATLAB.

Injectable dicalcium phosphate bone cement prepared from biphasic calcium phosphate extracted from lamb bone.

Quick setting and poor injectability due to liquid-solid phase separation have limited the clinical use of brushite and monetite cements. The presence of certain ions in the cement during the setting reaction moderate the setting time and properties of the cement. This study reports the preparation of injectable bone cement by using biphasic calcium phosphate (BCP) extracted from femur lamb bone by calcination at 1450 °C. EDX analysis infers the presence of Mg and Na ions as trace elements in BCP. X-ray diffraction patterns of the prepared cement confirmed the formation of brushite (DCPD) along with monetite (DCPA) as a minor phase. DCPA phase diminished gradually with a decrease in powder to liquid ratio (PLR). Initial and final setting time of 5.3 ±â€¯0.5 and 14.67 ±â€¯0.5 min respectively are obtained and within the acceptable recommended range for orthopedic applications. Exceptional injectability of ≈90% is achieved for all prepared bone cement samples. A decrease in compressive strength was observed with increase in the liquid phase of the cement, which is attributed to the higher degree of porosity in the set cement. Immersion of bone cement in simulated body fluid (SBF) for up to 7 days resulted in the formation of apatite layer on the surface of cement with Ca/P ratio 1.71, which enhanced the compressive strength from 2.88 to 9.15 MPa. The results demonstrate that bone cement produced from BCP extracted from femur lamb bone can be considered as potential bone substitute for regeneration and repair of bone defects.

Effect of Sintering on Di-Electric Characteristics of Al-Cu Doped Cobalt Ferrite Nanoparticles.

Aluminium substituted cobalt-copper Co1-xCuxFe2-xAlxO4, (x ═ 0.8) nanoparticles are grown and sintered at different temperature in the range 600 to 900 °C. XRD analysis on nanoparticles prepared at sintered temperatures of 700 °C and 800 °C confirms the spinel structure and presence of hematite phase (alpha ferrite) in them. The dielectric behaviour of the prepared nano-particles is investigated. Although crystallinity improved with increase in sintering temperature and there was a dielectric loss at higher probe analyser frequency. The synthesized nanoparticles an average particle size of 20-24 nm while the FTIR absorption in regions of 586-595 cm-1 and 450-460 cm-1 indicated the presence of intrinsic vibrations of the tetrahedral and octahedral complexes respectively. Electrical resistivity as a function of temperature confirms the semiconducting nature of the Cu-Al substituted cobalt ferrite, and is attributed to the hopping mechanism between Fe2+ Fe3+ ions and Co2+ Cu2+, Co2+ Al3+. The lower values of dielectric constants and dielectric losses make Al-Cu doped cobalt ferrite, a potential material for microwave and radio wave absorber applications.