Analysis of energy saving in user equipment in LTE-A using stochastic modelling

Telecommunication Systems - Energy saving in User Equipment (UE) is one of the important issues for limited sources of power in the device. It is critical for the UE to maximize its energy...     

Fabrication of low-loss IR-transmitting Ge30As10Se30Te30 glass fibers

Improved purification and processing techniques have been utilized to fabricate Ge₃₀As₁₀Se₃₀Te₃₀ glass fibers with a minimum loss of O.11 dB/m at 6.6 μm. This is the lowest loss reported for any telluride glass fiber in the infrared region. Furthermore, the fibers exhibit less than 1 dB/m loss between 5.25 and 9.5 μm     

Applications of chalcogenide glass optical fibers

Chalcogenide-glass fibers based on sulfide, selenide, telluride and their rare-earth-doped compositions are being actively pursued worldwide. Great strides have been made in reducing optical losses using improved chemical purification techniques, but further improvements are needed in both purification and fiberization technology to attain the theoretical optical losses. Despite this, chalcogenide-glass fibers are enabling numerous applications that include laser power delivery, chemical sensing, and imaging, scanning near field microscopy/spectroscopy, IR sources/lasers, amplifiers and optical switches.     

A novel one-pot method for the preparation of pyrazoles by 1,3-dipolar cycloadditions of diazo compounds generated in situ

A convenient one-pot procedure for the preparation of pyrazoles by 1,3-dipolar cycloaddition of diazo compounds generated in situ has been developed. Diazo compounds derived from aldehydes were reacted with terminal alkynes to furnish regioselectively 3,5-disubstituted pyrazoles. Furthermore, the reaction of N-vinylimidazole and diazo compounds derived from aldehydes gave exclusively 3-substituted pyrazoles in a one-pot process.     

Studies on controlled potential coulometric determination of gallium in sodium perchlorate and sodium thiocyanate

Controlled potential coulometric (CPC) studies were carried out for developing a method to determine gallium at milligram levels, in the mixed supporting electrolyte medium (4 M NaClO₄ + 0.5 M NaSCN), employing stirring mercury as a working electrode. Investigations for optimization of working electrode potentials, quantity of charge, level of background current and electrolysis time for achieving quantitative reduction of Ga(III) to Ga and its oxidation back to Ga(III), were undertaken. Effect of gallium content and interference of zinc in of gallium determination were also studied. The developed methodology was employed for the determination of gallium in pure Ga as well as in synthetic U + Ga mixture solutions. Accuracy and precision values of better than 0.5% were obtained at 1-2 mg levels.     

Mathematical Correction for Polyatomic Isobaric Spectral Interferences in Determination of Lanthanides by Inductively Coupled Plasma Mass Spectrometry

The determination of lanthanides by Inductively Coupled Plasma Mass Spectrometry (ICP‐MS) is complicated by several spectral overlaps from M⁺, MO⁺ or MOH⁺ ions formed in the ICP. Especially, it is essential to avoid the spectral interferences from lighter lanthanide and Ba polyatomic ions on middle or heavier lanthanides. To tackle this problem, we have developed a mathematical correction method, which reduces all the spectral overlaps from oxide species of Pr, Nd, Ce and Sm over Gd, Tb, Dy and Ho, and Gd, Tb over Yb and Lu. It can also successfully correct the oxide and hydroxide interference of Ba over Eu. The effectiveness of the proposed the mathematical correction scheme is demonstrated for the USGS Standard Rock samples AGV‐1 and G‐2. The results show that the experimental data obtained by applying the mathematical correction scheme for lanthanides is in good agreement with the reported values, using pneumatic and ultrasonic nebulisation methods, for their ICP‐MS analysis.