Double perovskite compounds (DPCs) have gained much more attention due to their versatile character in the fields of electronics and spintronics. Using density functional theory (DFT) we investigated the electronic, magnetic and optical properties of DPC La2BB′O6 where B = Cr, Sc and V and B′ = Co, Ni. The electronic band gaps suggest these compounds are half-metallic (HF) semiconductors in the spin-up channel and metallic in the spin-down channel. Magnetic properties suggest these are ferromagnetic in nature, so all DPCs are half-metallic ferromagnetic (HM-FM). Furthermore, the compound La2CrCoO6 shows outstanding electronic and optical properties, so it can be used in optoelectronic/spintronic devices.

The dielectric constant of CCTO materials can be as high as 104, which makes it suitable for use in electronic devices but the high dielectric loss limits its application. In this paper, a series of Sr and Zr co-doped CCTO ceramics having the formula Ca0.8Sr0.2Cu3Ti4−xZrxO12 (x = 0.1, 0.2, 0.3, 0.4) were obtained via a solid-state reaction technique. We force the effect of the Zr content on the phase composition, microstructure, cationic valence states, impedance, and dielectric properties of the as-prepared ceramics to reduce dielectric loss. The results demonstrate that Sr and Zr co-doping increases dielectric constant and reduces dielectric loss simultaneously, and the maximum dielectric constant (1.87 × 105, 1 Hz) and minimum dielectric loss (0.43, 102 Hz) are obtained when x = 0.3. Mixed Cu+/Cu2+ and Ti3+/Ti4+ valence states are observed to coexist in the co-doped material lattices, which promote dipole polarization, and thereby increase the dielectric constant of the ceramics. The dielectric properties of the materials are analyzed according to the internal barrier layer capacitance model, which elucidates the contributions of the grains and grain boundaries to dielectric performance. The maximum grain boundary resistance (3.7 × 105 Ω) is obtained for x = 0.3, which contributes toward the minimum dielectric loss (0.43) obtained for this ceramic at a frequency less than 1 kHz. The average grain sizes of the samples decrease with increasing Zr content, which is the primary factor increasing the grain boundary resistance of the co-doped ceramics.

Aggressive Driving behavior plays a key role in road safety as it is important in road traffic accident prevention. The aim of this study was to investigate the aggressive driving behavior attitude towards road safety issues in Pakistan and china and the applicability of three-factor structure (aggressive violations, ordinary violations and errors) of both version of driver behavior questionnaire (DBQ). T-test was conducted to evaluate significant differences and it exposed that Chinese sample is more significant. Confirmatory factor analysis was tested and calculated on both samples. Chinese samples fit the CFA statistics models best as compared to Pakistani sample. Additionally, Pakistan drivers especially the younger drivers were mostly engaged in aggression and errors, while Chinese drivers appeared more disciplined and rule followers.

Self-consolidating concrete (SCC) is a special concrete that is highly flow able, non-segregating and self-expanding. Self-compacted concrete (SCC) is poured into the formwork without compaction and fills the formwork by its own weight. SCC is considered to have many advantages. Compared with conventional concrete as improved Construction quality, faster construction activity, lower cost etc. This project was carried out to evaluate the effects of addition of nylon fiber and fly ash on the fresh and hardened properties of SCC mixes. In this project, concrete mixes with nylon fiber of 0.5%, 1.5%, 2.5%, and fly ash with 0%, 15%, 30% and 45% were used to determine its permeability, flow Capacity, evaluated on the basis of and separation resistance, slump flow, L-box and V-funnel tests. After 3 days, 14 days, 28 days of curing SCC cylinders, compressive and splitting tensile strength were tested. The test results show that nylon fibers increase permeability but decrease the filling capacity and segregation resistance of SCC. Furthermore, it can be concluded that after 3 days, 14 days, 28 days of curing, the test of concrete samples showed that the addition of nylon fiber up to 2.0% of cement by volume increased the compressive strength of SCC. Strength, improves tensile strength but 2.5%. Nylon fiber reduces the compressive strength, tensile strength of hardened SCC.