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Optical imaging has played a pivotal role in deciphering in vivo bioinformatics but is limited by shallow penetration depth and poor imaging performance owing to interfering tissue autofluorescence induced by concurrent photoexcitation. The emergence of near-infrared (NIR) self-luminescence imaging independent of real-time irradiation has timely addressed these problems. There are two main kinds of self-luminescent agents, namely inorganic and organic luminophores. Inorganic luminophores usually suffer from long-term biotoxicity concerns resulting from potential heavy-metal ions leakage and nonbiodegradability, which hinders their further translational application. In contrast, organic luminophores, especially organic semiconducting luminophores (OSLs) with good biodegradable potential, tunable design, and outstanding optical properties, are preferred in biological applications. This review summarizes the recent progress of OSLs used in NIR afterglow, chemiluminescence, and bioluminescence imaging. Molecular manipulation and nanoengineering approaches of OSLs are discussed, with emphasis on strategies that can extend the emission wavelength from visible to NIR range and amplify luminescence signals. This review concludes with a discussion of current challenges and possible solutions of OSLs in the self-luminescence field.  相似文献   
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Journal of Signal Processing Systems - This paper presents an algorithm-adaptable, scalable, and platform-portable generator for massive multiple-input multiple-output (MIMO) baseband processing...  相似文献   
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L-NG-nitroarginine (LNNA), an analog of L-arginine, is a competitive inhibitor of nitric oxide synthase which causes the selective reduction of blood flow to tumor cells. Despite the potential of LNNA to function as an adjuvant in cancer therapies, its poor solubility and stability have hindered the development of an injectable formulation of LNNA that is suitable for human administration. This work, for the first time, details a systematic study on the determination of equilibrium Ka constants and the rate law of LNNA degradation. The four Ka values of LNNA were determined to be 1.03, 1.10?×?10?2, 2.51?×?10?10, and 1.33?×?10?13 M. From the kinetic and equilibrium studies, we have shown that the deprotonated form of LNNA is the main form of LNNA that undergoes degradation in aqueous media at room temperature. The rate law of LNNA degradation was found to be first order with respect to OH? concentration and first order with respect to LNNA? concentration. The rate constant at 25?°C and 1?atm was determined to be 0.04453 M?1min?1. A base catalyzed mechanism of LNNA degradation was proposed based on the kinetic study. The mechanism was found to be very useful in explaining the discrepancies and changes of the rate law at different pH values. It is thus recommended that LNNA should be formulated as a concentrated solution in acidic conditions for maximum chemical stability during storage and be diluted with a basic solution to near physiological pH just before administration.  相似文献   
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石墨烯是一种新型的碳材料具有优异的光学、电学、热学性能,可制备高性能纳米复合材料。以氧化石墨烯( GO)为前驱体的一维纤维可提高其柔韧性和导电性。本文针对石墨烯及其复合材料的研究现状进行了简述,评论了石墨烯复合纤维的性能,并展望了其应用领域与发展前景。  相似文献   
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J.Y.R. Liew  W.F. Chen 《Thin》1994,20(1-4):17-47
A plastic hinge analysis based on a two-surface stiffness degradation model is outlined for second-order inelastic analysis of steel structures. The analysis approach is based on refinements to the elastic-plastic hinge method and allows for a smooth transition from initial yielding to the full yielding of cross-sections in a beam-column element. This analysis method shows a good representation of the inelastic structural response compared to the conventional elastic-plastic hinge analysis, and it is efficient for use in the analysis design of large-scale structures. Design implications, recommendations and case studies for use of refined plastic hinge analysis for direct frame design considering semirigid connection effects are presented.  相似文献   
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随着矿山开采深度增加,原岩温度亦不断升高,围岩放热是深部矿体热环境恶化的诱因之一,严重制约深部矿体的安全高效开采。为有效分析三山岛金矿深部巷道围岩热源灾害诱因,本文通过在三山岛不同中段现场钻取岩样,在实验室内进行加工,应用稳态法测试岩石放热系数,测试结果表明:围岩的热传导系数随地点不同亦有一定的差异,三山岛金矿岩石的平均热传导率为1.92,围岩的平均热传导率为1.79,借此可以分析围岩放热量,为深部降温提供基础数据。  相似文献   
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