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101.
Novel biological vascular conduits, such as decellularized tissue engineered vascular grafts (TEVGs) are hindered by high thrombogenicity. To mimic the antithrombogenic surface of native vessels with a continuous glycosaminoglycan layer that is present on endothelial cells (ECs), a hyaluronic acid (HA) modified surface is established, to effectively shield blood platelets from collagen‐triggered activation. Using the amine groups present on 4 mm diameter decellularized TEVGs, a continuous HA hydrogel coating is built via a bifunctional thiol‐reactive cross‐linker, thereby avoiding nonspecific collagen matrix cross‐linking. The HA hydrogel layer recreates a luminal wall, “hiding” exposed collagen from the bloodstream. In vitro blood tests show that adhered platelets, fibrinogen absorption, and fibrin formation on HA‐coated decellularized TEVGs are significantly lower than on uncoated decellularized TEVGs. The HA surface also inhibits macrophage adhesion in vitro. HA‐coated decellularized syngeneic rat aortae (≈1.5 mm diameter), and TEVGs in rat and canine models, respectively, are protected from aggressive thrombus formation, and preserve normal blood flow. Re‐endothelialization is also observed. HA‐coated TEVGs may be an off‐the‐shelf small‐diameter vascular graft with dual benefits: antithrombogenic protection and promotion of endothelium.  相似文献   
102.
Controllable actuation and coordinating motion of artificial self‐propelled micro/nanomotors to mimic the motile natural microorganism systems are of great significance for constructing intelligent nanoscale machines. In particular, inorganic oxide particles have shown considerable promise in implementation of synthetic micro/nanomotors, due to their unique features and active response to environmental stimuli. This work critically reviews the recent progress in inorganic oxide‐based micro/nanomotors and focuses on their propulsion response to chemical and physical stimuli, especially emphasizing and discussing operating principles in the single engine, adaptive navigation under composite‐driven powers, and intriguing collective behaviors. The impact of oxide structure, multiple fields in motion controllability, and interaction between grouped micro/nanomotors are explored. Practical applications of individual and assembled micro/nanomotors in environmental and biomedical fields are demonstrated, including the removal of pollutants, drug delivery, cancer therapy, and in vivo imaging. Finally, current challenges for the development of novel micro/nanomotors and possible constraints toward the defined structure and accumulated toxicity are discussed along with future opportunities and directions. Owing to their facile synthesis, impressive physicochemical performances, high biocompatibility, and versatile actuations, it is expected that the association of inorganic oxides with micro/nanomotors will bring new and unique capabilities to the field of active matter.  相似文献   
103.
从研究分析电子显示器供求关系出发,预测有源矩阵液晶显示器(AMLCDs)的世界市场.  相似文献   
104.
A new class of organic dielectrics, benzocyclobutenes, 1, are described and their application to the fabrication of thin film multichip modules is detailed. Key properties for3, a siloxy containing BCB derivative include low dielectric constant (2.7), low loss (0.008 at 1 MHz), low water absorption (0.25% after 24 h water boil) and high degree of planarization (>90% from one layer coverage). All other properties meet the requirements necessary for fabrication of thin film MCM structures.  相似文献   
105.
A method is described for the exact calculation of message length transition probabilities in asynchronous selective reject (SREJ) ALOHA channels with Poisson message arrivals. The formulas derived are used for exact calculation of the throughput characteristics of example SREJ-ALOHA channels which were previously analyzed using bounds or approximate methods  相似文献   
106.
An analytic perturbation solution to the nonlinear Schrodinger equation with loss Γ for both normal and anomalous dispersion is developed. Explicit results are obtained through second order in the perturbation Γ. The results show that the dark pulse spreads less rapidly than the bright one and that total spreading as well as the difference in spreading rate for the two types of pulses decreases with loss. Comparisons are made with a zeroth-order perturbation theory and with numerical simulations, which are found to bracket the second-order results  相似文献   
107.
High-quality, large (10 cm long and 2.5 cm diameter), nuclear spectrometer grade Cd0.9Zn0.1Te (CZT) single crystals have been grown by a controlled vertical Bridgman technique using in-house zone refined precursor materials (Cd, Zn, and Te). A state-of-the-art computer model, multizone adaptive scheme for transport and phase-change processes (MASTRAP), is used to model heat and mass transfer in the Bridgman growth system and to predict the stress distribution in the as-grown CZT crystal and optimize the thermal profile. The model accounts for heat transfer in the multiphase system, convection in the melt, and interface dynamics. The grown semi-insulating (SI) CZT crystals have demonstrated promising results for high-resolution room-temperature radiation detectors due to their high dark resistivity (ρ≈2.8 × 1011 Θ cm), good charge-transport properties [electron and hole mobility-life-time product, μτe≈(2–5)×10−3 and μτh≈(3–5)×10−5 respectively, and low cost of production. Spectroscopic ellipsometry and optical transmission measurements were carried out on the grown CZT crystals using two-modulator generalized ellipsometry (2-MGE). The refractive index n and extinction coefficient k were determined by mathematically eliminating the ∼3-nm surface roughness layer. Nuclear detection measurements on the single-element CZT detectors with 241Am and 137Cs clearly detected 59.6 and 662 keV energies with energy resolution (FWHM) of 2.4 keV (4.0%) and 9.2 keV (1.4%), respectively.  相似文献   
108.
The unique properties of the diamond‐like carbon (a:DLC), such as high mechanical hardness and abrasive resistance, optical transparency in the visible and IR spectral regions and high thermal conductivity, provide this material with advantages over other types of protecting materials for solar cells. Furthermore, the a:DLC films are inert to corrosive gases and other corrosive agents. Resistance to radiation damage of the a:DLC films deposited on solar cells is very important for space application. In the study we investigate the effect of electron damage on silicon solar cells coated with a:DLC films. We measure the I – V characteristic and the spectral response and calculate the values of the seven parameters of the double exponential solar cell model (usually not investigated) as a function of electron fluence irradiation. In addition we obtain also the usual external parameters Isc, Voc, Im, Vm, FF, and efficiency) of the solar cells. We investigate solar cells with and without anti‐reflecting coating coated with a:DLC films which were exposed to electron radiation. The main findings show that the solar cells with a:DLC films of thickness up to 500 nm degrade similarly to regular silicon cells exposed to electron irradiation. The degradation of the spectral response of the solar cell is mainly in the range of longer wavelengths and the irradiation affects the solar cell parameters (mainly the reverse saturation currents). Copyright © 2000 John Wiley & Sons, Ltd.  相似文献   
109.
Early channel reliance research compared different modes of communication to assess relationships among nonverbal and verbal cues. Emerging communication technologies represent a new venue for gaining insights into the same relationships. In this article, the authors advance a principle of interactivity as a framework for decomposing some of those relationships and report an experiment in which physical proximity—whether actors are in the same place ("co-located") or interacting at a distance ("distributed")—and the availability of other nonverbal environmental, auditory, and visual information in distributed modes is varied. Results indicate that both proximity and availability of nonverbal cues affect communication processes, social judgments participants make about each other, and task performance. The authors discuss implications about gains and losses due to presence of nonverbal features.  相似文献   
110.
The interfacial electronic structure between oxide thin films and organic semiconductors remains a key parameter for optimum functionality and performance of next‐generation organic/hybrid electronics. By tailoring defect concentrations in transparent conductive ZnO films, we demonstrate the importance of controlling the electron transfer barrier at the interface with organic acceptor molecules such as C60. A combination of electron spectroscopy, density functional theory computations, and device characterization is used to determine band alignment and electron injection barriers. Extensive experimental and first principles calculations reveal the controllable formation of hybridized interface states and charge transfer between shallow donor defects in the oxide layer and the molecular adsorbate. Importantly, it is shown that removal of shallow donor intragap states causes a larger barrier for electron injection. Thus, hybrid interface states constitute an important gateway for nearly barrier‐free charge carrier injection. These findings open new avenues to understand and tailor interfaces between organic semiconductors and transparent oxides, of critical importance for novel optoelectronic devices and applications in energy‐conversion and sensor technologies.  相似文献   
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