Trace impurity analysis is essential for the development of competitive silicon circuit technologies. Current best methods for chemically identifying and quantifying surface and near-surface impurities include grazing incidence x-ray fluorescence techniques using rotating anode x-ray sources. To date, this method falls short of what is needed for future process generations. However, the work described here demonstrates that with the use of synchrotron radiation, total reflection x-ray fluorescence methods can be extended to meet projected needs of the silicon circuit industry until, at least, the year 2000. The present results represent over an order of magnitude improvement in detection limit over what has been reported previously. A double multilayer monochromator on a high flux wiggler beam line resulted in a detection limit for Ni of 3×108 atoms/cm2. This is to be compared with a detection limit of 5×109 atoms/cm2 obtained with a rotating anode system. This is due to the greatly improved signal to background in the case of the synchrotron. Furthermore, there is a path to improving the synchrotron case to reach a detection limit of 5×107 atoms/cm2.

Adopting CO 2 as an alternative gas of SF 6 in a gas circuit breaker from the environmental viewpoint, a 72 kV-31.5 kA class CO 2 gas circuit breaker (CO 2-GCB) model, which does not contain SF 6 gas at all, was designed, and produced. In the CO 2-GCB model, some effective technologies for current interruption by CO 2 gas were adopted; namely, puffer pressure enhancing techniques utilizing arc energy during a current interruption and ablation phenomena of a polymer element located in the puffer cylinder. As a result of current interruption and electric insulation tests, the CO 2-GCB model achieved practical levels of performance. Furthermore, it was found by carrying out a life cycle assessment (LCA) that the CO 2-GCB model could reduce the global warming impact by about 40% compared to the latest SF 6 gas circuit breaker in the same rating for 20 years operation including one maintenance opportunity.

Although the online campaigns of anti-vaccine advocates, or anti-vaxxers, severely threaten efforts for herd immunity, their propaganda strategies remain poorly understood, as does their reply behavior, which constitutes the most direct form of outreach on social media. Therefore, we empirically analyzed the strategy of anti-vaxxers' reply behavior on Twitter in terms of interaction frequency, content, and targets. Among the results, anti-vaxxers more frequently conducted reply behavior to other clusters, especially to neutral accounts, and the content of their replies was significantly toxic and emotional. Furthermore, the most-targeted users were so-called "decent" accounts with large numbers of followers, including accounts related to health care or representing scientists, policymakers, or media figures or outlets. We discussed and evaluated the effectiveness of these reply strategies, as well as the possible countermeasures to them. Those findings should prove useful for developing guidelines for pro-vaxxers and fact-checkers in online communities.

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We apply the wave-kinetic approach to study nonlinearly coupled Rossby wave-zonal flow fluid turbulence in a two-dimensional rotating fluid. Specifically, we consider for the first time nonlinear excitations of zonal flows by a broad spectrum of Rossby wave turbulence. Short-wavelength Rossby waves are described here as a fluid of quasi-particles, and are referred to as the 'Rossbyons'. It is shown that Reynolds stresses of Rossbyons can generate large-scale zonal flows. The result should be useful in understanding the origin of large-scale planetary and near-Earth atmospheric circulations. It also provides an example of a turbulent wave background driving a coherent structure.