We have demonstrated that the island nucleation in the initial stage of epitaxial thin film growth can be tuned by substrate surface charge doping. This charge effect was investigated using spin density functional theory calculation in Fe-deposition on graphene substrate as an example. It was found that hole-doping can noticeably increase both Fe-adatom diffusion barrier and Fe interadatom repu...

Delta doping techniques have been investigated to enhance the p-type doping of ZnSe. Tellurium was used as a codopant for improving the nitrogen doping efficiency. The net acceptor concentration (NA2ND) increased to 1.5310 18 cm using single d doping of N and Te ~N1Te!, while it was limited to 8310 cm by d doping of N alone. A promising approach was developed in which three consecutive d-doped ...

It is widely recognized that the effect of doping into a Mott insulator is complicated and unpredictable, as can be seen by examining the Hall coefficient in high Tc cuprates. The doping effect, including the electron-hole doping asymmetry, may be more straightforward in doped organic Mott insulators owing to their simple electronic structures. Here we investigate the doping asymmetry of an org...

For doping control, analyses of samples are generally achieved in two steps: a rapid screening and, in the case of a positive result, a confirmatory analysis. A two-step methodology based on ultra-high-pressure liquid chromatography coupled to a quadrupole time-of-flight mass spectrometry (UHPLC-QTOF-MS) was developed to screen and confirm 103 doping agents from various classes (e.g., beta-bloc...

ZnO nanowires (NWs) are used as building blocks for a wide range of different devices, e.g. light emitters, resonators, and sensors. Integration of the NWs into such structures requires a high level of NWs' diameter control. Here, we present that the doping concentration of Zn x Al1-x O and Zn x Ga1-x O seed layers has a strong impact on the NW growth and allows to tune the diameter of the NWs ...

BACKGROUND Doping attitude is a key variable in predicting athletes' intention to use forbidden performance enhancing drugs. Indirect reaction-time based attitude tests, such as the implicit association test, conceal the ultimate goal of measurement from the participant better than questionnaires. Indirect tests are especially useful when socially sensitive constructs such as attitudes towards ...

Photoelectrochemical water oxidation on hematite has been extensively studied, yet the relationship between the various facets exposed, heteroatom doping, and associated electrocatalytic activity has not been adequately explored. Here, hematite nanocrystals were synthesized with continuous tuning of the aspect-ratio and fine control of the surface area ratio of the (0001) facet with respect to ...

PbS quantum dots (QDs) are remarkable semiconducting materials, which are compatible with low-cost solution-processed electronic device fabrication. Understanding the doping of these materials is one of the great research interests, as it is a necessary step to improve the device performance as well as to enhance the applicability of this system for diverse optoelectronic applications. Here, we...

BACKGROUND Social science studies of doping practices in sport rely predominantly on self-reports. Studies of psychoactive drug use indicate that self-reporting is characterised by under-reporting. Likewise doping practice is likely to be equally under-reported, if not more so. This calls for more sophisticated methods for such reporting and for independent, objective validation of its results....

BACKGROUND Despite the development of advanced drug testing systems, both deliberate and inadvertent doping in sports is increasing in elite, amateur and school sports. As a result, alternative approaches that seek to influence an athlete's attitudes are needed to address the growing doping concerns that threaten both the health and well being of the athlete as well as the legitimacy of the spo...