The Utilization of Private Automobiles

The excessive and spontaneous increase in the number of privately owned automobiles that is presently seen in the economically developed capitalist countries has posed complex economic and social problems by overburdening roads and streets, impeding the development of public transit, polluting the environment, necessitating the neutralization of transport noise, causing significant resources to be channeled into the production and servicing of private automobiles, etc. In the United States, for example, the one-sided orientation toward the privately owned automobiles has not only not solved the transportation problem but at the same time has brought the public transit system to such a critical state that in November 1974 President G. Ford had to sign an act authorizing the payment of $11.8 billion in subsidies to public transit over a period of sixyears. Experts consider even this amount to be too small. (>u>1>/u>)

Comparative study on the creation of ferromagnetic properties in Fe/Co-doped lanthanum-oxide ceramics: role of the hydrogenation

Lanthanum oxide (Lanthana-La2O3) doped with Fe and Co nanoparticles was synthesized by a co-precipitation method. These synthesized samples were systematically characterized and studied using several measuring techniques: X‐ray fluorescence (XRF), X-ray diffraction (XRD), and UV-visible optical spectroscopy. Moreover, magnetization measurements were performed to study the elemental content analysis, crystalline structure, and optical bandgap and created ferromagnetic magnetic properties respectively. These measurements were aimed to investigate the structural and optical properties and the possibility of the creation of room-temperature ferromagnetic (RT-FM) properties in a host lanthana ceramic doped by Fe and Co ions, which could transform the La2O3 ceramic into a dilute magnetic semiconductor (DMS). The bandgap of the synthesized lanthana nanoparticles (NPs) was found to be significantly redshifted (~50–60%) by Fe/Co doping. The main objective of the present study is to investigate the significant effect of hydrogenation on the ferromagnetic properties of Fe- and Co-doped lanthanum-oxide ceramics. The results in this work indicate that the hydrogenation of the host NPs played an essential role in creating the RT-FM properties. The experimental results also showed that the magnetization obtained in La2O3 doped with Co ions was enhanced approximately by about three times higher than when Fe ions were doped. The obtained results were reported and discussed