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Tattooing is a ubiquitous body modification involving the injection of ink and/or dye pigments into the dermis. Biosensors in the form of tattoos can be used to monitor metabolites in interstitial fluid. Here, minimally invasive, injectable dermal biosensors were developed for measuring pH, glucose, and albumin concentrations. The dermal pH sensor was based on methyl red, bromothymol blue, and phenolphthalein, which responded to a pH range from 5.0 to 9.0. The dermal glucose sensor consisted of glucose oxidase, 3,3′,5,5′‐tetramethylbenzidine, and peroxidase that detected concentrations up to 50.0 mmol L?1. The dermal albumin sensor consisted of 3′,3′′,5′,5′′‐tetrachlorophenol‐3,4,5,6‐tetrabromosulfophthalein to measure concentrations up to 5.0 g L?1. The sensors were multiplexed in ex vivo skin tissue and quantitative readouts were obtained using a smartphone camera. These sensors can be used to manage of acid–base homeostasis, diabetes, and liver failure in point‐of‐care settings.  相似文献   
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The real time evolution and relaxation of expectation values of quantum fields and of quantum states are computed as initial value problems by implementing the dynamical renormalization group (DRG). Linear response is invoked to set up the renormalized initial value problem to study the dynamics of the expectation value of quantum fields. The perturbative solution of the equations of motion for the field expectation values of quantum fields as well as the evolution of quantum states features secular terms, namely terms that grow in time and invalidate the perturbative expansion for late times. The DRG provides a consistent framework to resum these secular terms and yields a uniform asymptotic expansion at long times. Several relevant cases are studied in detail, including those of threshold infrared divergences which appear in gauge theories at finite temperature and lead to anomalous relaxation. In these cases the DRG is shown to provide a resummation akin to Bloch-Nordsieck but directly in real time and that goes beyond the scope of Bloch-Nordsieck and Dyson resummations. The nature of the resummation program is discussed in several examples. The DRG provides a framework that is consistent, systematic, and easy to implement to study the non-equilibrium relaxational dynamics directly in real time that does not rely on the concept of quasiparticle widths.  相似文献   
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欧发  蔡永强 《物理学报》1988,37(2):330-334
本文从慢包络近似的麦克斯韦方程出发,在优质腔极限下,结合腔的边界条件与平均场极限,建立了适用于任何物质的光学双稳系统及相应的激光系统的动力学方程;并通过对方程的线性稳定性分析,得到了一个普适性的失稳判据。 关键词:  相似文献   
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Starting from ketone III several acyl derivatives of 4-aminomethyl-9,10-dihydro-4H-benzo[4,5]cyclohepta-[1,2--6]thiophene (VII) have been synthesized. The intramolecular cyclization of some of these new amides through the Bischler-Napieralski reaction is described.  相似文献   
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The standard potentials of AgCl + 12H2 = Ag+HCl in water +10, +20, and +30 mass per cent of acetonitrile were obtained in a cell without liquid junction, using as reference electrode the standard hydrogen electrode. They were determined at eight temperatures ranging from 298.15 to 263.15 K at intervals of 5 K. Hydrochloric acid solutions from 0.01 to 0.10 mol·kg?1 were used. The Debye-Hückel theory and the standard potentials were used to calculate the mean activity coefficients for HCl in the solvents. The results were used to obtain the standard thermodynamic functions for the acidic dissociation of HCl in the solvents. High values of HCl activity coefficients were obtained, suggesting that the acid is completely dissociated in the mixed solvents.  相似文献   
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