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This paper shows that a conventional semi-custom design-flow based on a energy efficient adiabatic logic (EEAL) cell library allows any VLSI designer to design and verify complex adiabatic arithmetic units in a simple way, thus, enjoying the energy reduction benefits of adiabatic logic. A family of semi-custom EEAL-based 32-bit carry-lookahead adder (CLA) has been designed in a TSMC 90-nm CMOS process technology and verified by CADENCE Design suite. Differential cascode voltage swing (DCVS) logic has been used to implement the newly proposed EEAL and it uses only a sinusoidal clock supply to ensure correct operation. Post-layout simulations show that semi-custom adiabatic arithmetic units can save significant amount of energy, as compared to the previously reported single clocked adiabatic logic and logically equivalent static CMOS implementation. Extensive CADENCE simulations have been done for the verification of the functionality of the proposed logic structure.

An experimental study on pressure drop and heat transfer in single-phase was carried out using 10 types of internally helical-grooved and smooth small-diameter tubes with an outside diameter of 4 mm. The results are listed below: (1) In the turbulent flow region, fin height had the greatest effect, helix angle had only a minor effect, and the number of grooves had almost no effect upon the pressure drop versus the mass flow rate of the 4-mm grooved small-diameter tubes. In the laminar flow region, except for fin height, the shapes of the internal grooves had scarcely any effect upon pressure drop. (2) In the turbulent flow region, the heat transfer coefficients of the 4-mm grooved small-diameter tubes were greatly affected by fin height. The heat transfer coefficients became the maximum when a helix angle was near 15°, and there is a different tendency in the experiments of the pressure drop. On the other hand, there is almost no effect of the number of grooves. In the laminar flow region, there were no large differences in the heat transfer coefficients between the internally helical-grooved tubes and smooth small-diameter tube. (3) New empirical correlations for the friction factor and heat transfer coefficient in the laminar and turbulent flow regions were developed based on the experimental values. (4) The performance assessment in consideration of both heat transfer and pressure drop was indicated by using Colburn's analogy.

In this research, influence of adding Li₂CO₃ (at 0%, 2%, 4%, 6%) on electrical and magnetic properties of ${\text{Ni}}_{0.6}$${\text{Mg}}_{0.4}$Fe₂O₄ (with 60% Ni and 40% Mg) ferrite has been studied. The samples are prepared by solid state reaction method and sintered at 1300^∘C for 6h. X-ray diffraction (XRD) patterns show the samples belong to single-phase cubic structure without any impurity phase. The magnetic properties (saturation magnetization and coercivity) of the samples have been investigated by VSM and found that the higher concentration of Li₂CO₃ reduces the hysteresis loss. DC resistivity increases with Li₂CO₃ contents whereas it decreases initially and then becomes constant at lower value with temperature which indicates that the studied samples are semiconductor. The dielectric dispersion occurs at a low-frequency regime and the loss peaks are formed in a higher frequency regime, which are due to the presence of resonance between applied frequency and hopping frequency of charge carriers. Notably, the loss peaks are shifted to the lower frequency with Li₂CO₃ additions.