Xi'an Jiaotong University

About: Xi'an Jiaotong University is a education organization based out in Xi'an, China. It is known for research contribution in the topics: Heat transfer & Dielectric. The organization has 85440 authors who have published 99682 publications receiving 1579683 citations. The organization is also known as: '''Xi'an Jiaotong University''' & Xi'an Jiao Tong University.

Use of two structurally similar small molecular acceptors enabling ternary organic solar cells with high efficiencies and fill factors

Abstract: Ternary blends have shown great potential to increase the power conversion efficiency (PCE) of organic solar cells (OSCs) In this work, we studied a ternary OSC system with a donor polymer (PM6) and two structurally similar non-fullerene acceptors (named ITCPTC and MeIC) Although these two small molecular acceptors (SMAs) exhibit similar absorption spectra, they introduce a surprising synergistic effect on tuning the domain size and crystallinity of the OSC blend More specifically, MeIC is a SMA with strong crystallinity, which results in excessive phase segregation and large domain size for the PM6:MeIC binary blend By adding a structurally similar and less crystalline SMA (ITCPTC) into the binary blend, the domain size and morphology of the blend are much improved without sacrificing the electron mobility of the blend As a result, the optimal blend ratio of PM6 : ITCPTC : MeIC (1 : 04 : 06) led to an impressive FF of 782% and PCE of 1413%, which are the highest values reported for ternary non-fullerene OSCs reported to date

Roadmap on optical rogue waves and extreme events

Abstract: The pioneering paper 'Optical rogue waves' by Solli et al (2007 Nature 450 1054) started the new subfield in optics. This work launched a great deal of activity on this novel subject. As a result, the initial concept has expanded and has been enriched by new ideas. Various approaches have been suggested since then. A fresh look at the older results and new discoveries has been undertaken, stimulated by the concept of 'optical rogue waves'. Presently, there may not by a unique view on how this new scientific term should be used and developed. There is nothing surprising when the opinion of the experts diverge in any new field of research. After all, rogue waves may appear for a multiplicity of reasons and not necessarily only in optical fibers and not only in the process of supercontinuum generation. We know by now that rogue waves may be generated by lasers, appear in wide aperture cavities, in plasmas and in a variety of other optical systems. Theorists, in turn, have suggested many other situations when rogue waves may be observed. The strict definition of a rogue wave is still an open question. For example, it has been suggested that it is defined as 'an optical pulse whose amplitude or intensity is much higher than that of the surrounding pulses'. This definition (as suggested by a peer reviewer) is clear at the intuitive level and can be easily extended to the case of spatial beams although additional clarifications are still needed. An extended definition has been presented earlier by N Akhmediev and E Pelinovsky (2010 Eur. Phys. J. Spec. Top. 185 1-4). Discussions along these lines are always useful and all new approaches stimulate research and encourage discoveries of new phenomena. Despite the potentially existing disagreements, the scientific terms 'optical rogue waves' and 'extreme events' do exist. Therefore coordination of our efforts in either unifying the concept or in introducing alternative definitions must be continued. From this point of view, a number of the scientists who work in this area of research have come together to present their research in a single review article that will greatly benefit all interested parties of this research direction. Whether the authors of this 'roadmap' have similar views or different from the original concept, the potential reader of the review will enrich their knowledge by encountering most of the existing views on the subject. Previously, a special issue on optical rogue waves (2013 J. Opt. 15 060201) was successful in achieving this goal but over two years have passed and more material has been published in this quickly emerging subject. Thus, it is time for a roadmap that may stimulate and encourage further research.

Structure and in vitro bioactivity of titania-based films by micro-arc oxidation

Abstract: Titania-based films on titanium were formed by micro-arc oxidation in electrolytic solutions containing sodium carbonate, sodium phosphate, acetate monohydrate and β-glycerophosphate disodium salt pentahydrate using a pulse power supply. The morphology, elemental composition and phase components of the films were investigated as a function of the electrolytes composition and the applied voltage (in the range of 200–500 V). In vitro bioactivity of the films was evaluated in a most commonly used simulated body fluid as proposed by Kokubo et al. The results showed that the films were porous with 1–8 μm pores and nano-crystallized, without apparent interface to the titanium substrates. The phase components of the films could be anatase, rutile, CaTiO 3 , β-Ca 2 P 2 O 7 and α-Ca 3 (PO 4 ) 2 , strongly depending on the electrolytes composition and the applied voltage. The pore size and the content of Ca and P tended to increase with the applied voltage. Among the prepared titania-based films, only the film containing CaTiO 3 , β-Ca 2 P 2 O 7 and α-Ca 3 (PO 4 ) 2 could induce an apatite layer on its surface, exhibiting bioactivity. The bioactive response of the micro-arc oxidized films to the structural factors and the apatite-induced mechanism were discussed.