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91.
Obtaining quantitative information about molecular assemblies with high spatial and temporal resolution is a challenging task in fluorescence microscopy. Single‐molecule techniques build on the ability to count molecules one by one. Here, a method is presented that extends recent approaches to analyze the statistics of coincidently emitted photons to enable reliable counting of molecules in the range of 1–20. This method does not require photochemistry such as blinking or bleaching. DNA origami structures are labeled with up to 36 dye molecules as a new evaluation tool to characterize this counting by a photon statistics approach. Labeled DNA origami has a well‐defined labeling stoichiometry and ensures equal brightness for all dyes incorporated. Bias and precision of the estimating algorithm are determined, along with the minimal acquisition time required for robust estimation. Complexes containing up to 18 molecules can be investigated non‐invasively within 150 ms. The method might become a quantifying add‐on for confocal microscopes and could be especially powerful in combination with STED/RESOLFT‐type microscopy.  相似文献   
92.
Input–output datasets from two magnetic confinement fusion (MCF) experiments of the reversed-field pinch (RFP) type are examined. The RFP datasets, which are samples of the distributed magnetic field dynamics, are naturally divided into many smaller batches due to the pulsed-plasma operation of the experiments. The two RFP experiments considered are (i) EXTRAP T2R (T2R) with 64 inputs and 64 outputs and (ii) RFX-mod (RFX) with 192 inputs and 192 outputs. Both T2R and RFX are magnetohydrodynamically unstable and operates under magnetic feedback with optional dither injection. Using subspace system identification techniques and randomised cross-validation (CV) methods to minimise the generalisation error, state-space orders of the empirical systems are suggested. These system orders are compared to “stabilisation diagrams” commonly used in experimental modal analysis practice. The relation of the CV system order to the decay of the singular values from the subspace method is observed. Both (i) stable vacuum diffusion and (ii) unstable plasma response datasets are analysed. Apparent simulation and prediction errors are quantified for both cases using a deviation-accounted-for index. These results are purely data-driven. A simple approach towards exploitation of the subspace techniques for finite-element model refinement and data confrontation is presented.  相似文献   
93.
The paper gives a summary of the existing results about algorithmic analysis of probabilistic pushdown automata and their subclasses.  相似文献   
94.
In this paper, we analyse a systematically designed and easily tunable backstepping-based boundary control concept for a gantry crane with heavy chain and payload. The corresponding closed-loop system is formulated as an abstract evolution equation in an appropriate Hilbert space. Non-restrictive conditions for the controller coefficients are derived, under which the solutions are described by a C0-semi-group of contractions, and are asymptotically stable. Moreover, by applying Huang's theorem we can finally even show that under these conditions the controller renders the closed-loop system exponentially stable.  相似文献   
95.
An interference of heavy-fermion superconductivity (SC) and antiferromagnetism (AFM) has been studied in the framework of the periodic Anderson model with the superexchange interaction between localized electrons. It has been shown that pressure-induced energy change of the localized states leads to modifying antiferromagnetic and superconducting order parameters. Conditions have been found for the coexistence of SC and AFM in the model. Theoretical results of the pressure effects on the ground state character of the heavy-fermion systems are in good agreement with experimental data for a rare-earth intermetallic compound CeRhIn5. The divergence of the effective electron mass produced by suppressing the long-range antiferromagnetic order has also been analyzed in the same framework.  相似文献   
96.
In the field of humidity quantities, the first CIPM key comparison, CCT-K6 is at its end. The corresponding European regional key comparison, EUROMET.T-K6, was completed in early 2008, about 4?years after the starting initial measurements in the project. In total, 24 NMIs from different countries took part in the comparison. This number includes 22 EURAMET countries, and Russia and South Africa. The comparison covered the dew-point temperature range from ?50?°C to +20?°C. It was carried out in three parallel loops, each with two chilled mirror hygrometers as transfer standards in each loop. The comparison scheme was designed to ensure high quality results with evenly spread workload for the participants. It is shown that the standard uncertainty due to the long-term instability was smaller than 0.008?°C in all loops. The standard uncertainties due to links between the loops were found to be smaller than 0.025?°C at ?50?°C and 0.010?°C elsewhere. Conclusions on the equivalence of the dew-point temperature standards are drawn on the basis of calculated bilateral degrees of equivalence and deviations from the EURAMET comparison reference values (ERV). Taking into account 16 different primary dew-point realizations and 8 secondary realizations, the results demonstrate the equivalence of a large number of laboratories at an uncertainty level that is better than achieved in other multilateral comparisons so far in the humidity field.  相似文献   
97.
Sharp indentation test have been studied very frequently in recent years and the fundamental knowledge of the mechanics of such test has reached some maturity. Such studies also include the correlation between residual stresses and the global properties, i.e., hardness and size of the contact area. The investigations presented have been based on experimental, theoretical, and numerical methods and as a result, the basic features of the problem are fairly well understood but quantitative relations, for the determination of residual stresses using sharp indentation, have been proven to be less accurate and accordingly not suitable for a practical situation, in particular so at predominantly compressive residual stresses. It is therefore the aim of the present study to investigate this matter in some detail and to determine possible mechanisms for the difference in indentation behavior between tension and compression and, with this as a background, determine relations suitable for a quantitative determination of the residual fields. The present analysis is based on theoretical and numerical methods and in the latter case, the finite element method is relied upon. Classical Mises elastoplastic material behavior is assumed throughout the investigation.  相似文献   
98.
We report a simple one-step synthesis method of large single crystalline Ag (111) hexagonal microplates with sharp edges and a size of up to tens of microns. Single silver crystals were produced by reduction silver nitrate aqueous solution with 4-(methylamino)phenol sulfate. Scanning and transmission electron microscopy, energy-dispersive X-ray spectroscopy, selected area electron diffraction and optical microscopy techniques were combined to characterize the crystals. It is shown that the microplates can be easily dispersed and transferred as single objects onto different substrates and subsequently used as a high quality plasmonic starting material for micromachining of future nanocomponents, using modern top-down techniques like focused-ion beam milling and gas injection deposition.  相似文献   
99.
Process intensification in distillation systems has received much attention during past decades, with the aim of increasing both energy and separation efficiency. Various techniques, such as internal heat‐integrated distillation, membrane distillation, rotating packed bed, dividing‐wall columns and reactive distillation were studied and reported in the literature. All these techniques employ the conventional continuous counter‐current contact of vapor and liquid phases. Cyclic distillation technology is based on an alternative operating mode using separate phase movement which leads to key practical advantages in both chemical and biochemical processes. This article provides a mini‐review of cyclic distillation technology. The topics covered include the working principle, design and control methods, main benefits and limitations as well as current industrial applications. Cyclic distillation can be rather easily implemented in existing columns by simply changing the internals and the operating mode, thus bringing new life to old distillation towers by significantly increasing the column throughput, reducing the energy requirements and offering better separation performance. © 2016 Society of Chemical Industry  相似文献   
100.
Throughout history, distillation has been the most widespread separation method. However, despite its simplicity and flexibility, distillation still remains very energy inefficient. Novel distillation concepts based on process intensification, can deliver major benefits, not just in terms of significantly lower energy use, but also in reducing capital investment and improving eco‐efficiency. While very likely to remain the separation technology of choice for the next decades, there is no doubt that distillation technology needs to make radical changes in order to meet the demands of the energy‐conscious modern society. This article aims to show that in spite of its long age, distillation technology is still young and full of breakthrough opportunities. Moreover, it provides a broad overview of the recent developments in distillation based on process intensification principles, for example heat pump assisted distillation (e.g. vapor compression or compression–resorption), heat‐integrated distillation column, membrane distillation, HiGee distillation, cyclic distillation, thermally coupled distillation systems (Petlyuk), dividing‐wall column, and reactive distillation. These developments as well as the future perspectives of distillation are discussed in the context of changes towards a more energy efficient and sustainable chemical process industry. Several key examples are also included to illustrate the astonishing potential of these new distillation concepts to significantly reduce the capital and operating cost at industrial scale. © 2013 Society of Chemical Industry  相似文献   
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