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A novel anthracene derivative, disilanyl double-pillared bisanthracene ([sup.Si]DPBA), has been recently synthesized, which effectively functions as a bipolar carrier transport material in OLEDs. Its charge transport properties have been systemically investigated by band model and hopping model. Band structure calculations of [sup.Si]DPBA show that the dispersions of the larger valence band and conduction band are comparable, which demonstrates that both electron and hole are favoured for transport, and that [sup.Si]DPBA has the potential to be used as bipolar transport material from the viewpoint of band model. The density of states and transfer integrals in the main pathways show that it is the edge-to-face CH***π interaction that determines the charge transport property, and that the Si[Me.sub.2] group contibutes little to it. The calculated charge mobilities of holes and electrons are 0.461 and 0.116 [cm.sup.2]*[V.sup.-1]*[s.sup.-1], respectively. They are the same order of magnitude, and the electron mobility is on the order of magnitude of perylene-3,4:9,10-tetracarboxylic acid bisimide (PBI) derivatives (0.34 [cm.sup.2]*[V.sup.-1]*[s.sup.-1]). Both models demonstrate that [sup.Si]DPBA has the potential to be used as a bipolar transport material. Key words: disilanyl double-pillared bisanthracene ([sup.Si]DPBA), charge transport, band model, hopping model. On a recemment realise la synthese d'un nouveau derive de l'anthracene, un disilanyl bisanthracene a double pilier (<< [sup.Si]DPBA ?) qui fonctionne effectivement comme un materiel de transfert de charge bipolaire dans les diodes electroluminescentes organiques (DELO). On a etudie d'une facon systematique ses proprietes de transfert de charge par le modele de bande et le modele des sauts. Les calculs de structure de bande pour le ? [sup.Si]DPBA ≫ montrent que les dispersions de la bande de valence (BV) la plus large et de la bande de conduction (BC) sont comparables, ce qui demontre que, selon le modele de la bande de conduction, l'electron et le trou favorisent tous les deux le transport et que le ? [sup.Si]DPBA ? a la capacite d'etre utilise comme materiel de transfert de charge. La densite des etats et les integrales de transfert dans les voies principales montrent que la propriete de transfert de charge est determinee par l'interaction CH***π entre l'arete et la face et que la contribution du groupe Si[Me.sub.2] est minime. Les mobilites de charge du trou et de l'electron sont respectivement de 0 461 et 0 116 [cm.sup.2]*[V.sup.-1]*[s.sup.-1]. Elles sont du meme ordre de grandeur et la mobilite de l'electron est du meme ordre de grandeur que celle des derives bisimides de l'acide perylene-3,4 :9,10-tetracarboxylique (BIP), soit 0,34 [cm.sup.2]*[V.sup.- 1]*[s.sup.-1]. Les deux modeles montrent que le ? [sup.Si]DPBA ? a le potentiel pour etre utilise comme materiel de transfert de charge bipolaire. Mots-cles : disilanyl bisanthracene a double pilier (? [sup.Si]DPBA ?), transfert de charge, modele de bande, modele des sauts. [Traduit par la Redaction], Introduction In recent years, organic semiconductors have attracted considerable attention because of their potential applications, such as organic light-emitting diodes (OLED), (1-7) organic field effect transistors (OFETs), (8-10) organic thin-film [...]

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Objective: To solve the ESB bus performance and safety problems caused by the explosive growth of the hospital's business, and to ensure the stable interaction of the hospital's business system., Methods: Taking the construction of our hospital's information system as an example, we used AlwaysOn, load balancing and other technologies to optimize the ESB bus architecture to achieve high availability and scalability of the hospital's ESB bus., Results: The ESB bus high-availability architecture effectively eliminates multiple points of failure. Compared with the traditional dual-machine Cluster solution, the security is significantly improved. The nodes based on load balancing can be scaled horizontally according to the growth of the hospital's business volume., Conclusions: The construction of the ESB bus high-availability architecture effectively solves the performance and security issues caused by business growth, and provides practical experience for medical information colleagues. It has certain guiding significance for the development of regional medical information.

In this paper, a four-channel pulse-triggered functional electrical stimulator using complementary current source and time division output method is proposed for the research and application of functional electrical stimulation (FES). The high-voltage compliance and output impedance is increased by adopting the complementary current source, which can also realize the linear voltage-to-current conversion and high channel isolation. A high-voltage analog switch chip MAX14803, combined with a FIFO queue algorithm in the microprocessor, is used to setup the H-bridge and multiplexers for the four-channel time division multiplexing output. With this method, the size and cost of the key components are reduced greatly. The stimulating core circuit area is 30 × 50 mm(2). According to the experiments, the stimulator can achieve the four-channel charge-balanced biphasic stimulation with a current range between 0 and 60 mA and a single-phase pulse amplitude up to 60 V.