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Zusammenfassung Es wird auf eine Methode hingewiesen, die es ermöglicht, in Gaswerks- und Kokereiabwässern hohe, geringe und geringste Cyanid-Ionenkonzentrationen in Gegenwart von Hexacyanoferraten quantitativ exakt zu erfassen. Die Ergebnisse werden mit denen der in dieser Zeitschrift3 dargelegten Methoden verglichen.
Summary A method is recommended for the exact quantitative determination of high, law, and lowest concentrations of cyanide in presence of hexacyanoferrates in effluents from gas works and coke-oven plants. The results are compared with those of a method published earlier in this journal3.
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The analysis of single living cells, including intracellular delivery and extraction, is essential for monitoring their dynamic biochemical processes and exploring intracellular heterogeneity. However, owing to the 2D view in bright-field microscopy and optical distortions caused by the cell shape and the variation in the refractive index both inside and around the cells, achieving spatially undistorted imaging for high-precision manipulation within a cell is challenging. Here, an accurate and visual system is developed for single-cell spatial manipulation by correcting the aberration for simultaneous bright-field triple-view imaging. Stereo information from the triple view enables higher spatial resolution that facilitates the precise manipulation of single cells. In the bright field, we resolved the spatial locations of subcellular structures of a single cell suspended in a medium and measured the random spatial rotation angle of the cell with a precision of ±5°. Furthermore, we demonstrated the visual manipulation of a probe to an arbitrary spatial point of a cell with an accuracy of <1 pixel. This novel system is more accurate and less destructive for subcellular content extraction and drug delivery.

We achieved the low-damage spatial puncture of single cells at specific visual points with an accuracy of <65 nm.  相似文献   
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Multiple strategies to overcome the intrinsic limitations of the oxygen evolution reaction (OER) have been proposed by numerous research groups. Despite the substantial efforts, the driving force required for water oxidation is largely making the reaction inefficient. In the present work, we collected published studies involving DFT calculations for the OER, with the purpose to understand why the progress made so far, for lowering the overpotential of the reaction, is relatively small. The data revealed that the universal scaling relationship between HO* and HOO* intermediates is still present and robust, despite the variety in methods and structures used for calculating the binding energies of the intermediates. On the other hand, the data did not show a clear trend line regarding the O* binding. Our analysis suggested that trends in doped semiconducting oxides behave very differently from those in other oxides. This points towards a computational challenge in describing doped oxides in a realistic manner. We propose a way to overcome these computational challenges, which can be applied to simulations corresponding to doped semiconductors in general.

Multiple strategies to overcome the intrinsic limitations of the oxygen evolution reaction (OER) have been proposed by numerous research groups.  相似文献   
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Contrasts between beta relaxation in equilibrium viscous liquids and glasses are rationalized in terms of a double-well potential model with structure-dependent asymmetry, assuming structure is described by a single order parameter. The model is tested for tripropylene glycol where it accounts for the hysteresis of the dielectric beta loss peak frequency and magnitude during cooling and reheating through the glass transition.  相似文献   
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Background  

The archaeal exosome is formed by a hexameric RNase PH ring and three RNA binding subunits and has been shown to bind and degrade RNA in vitro. Despite extensive studies on the eukaryotic exosome and on the proteins interacting with this complex, little information is yet available on the identification and function of archaeal exosome regulatory factors.  相似文献   
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Joint models for longitudinal and survival data are routinely used in clinical trials or other studies to assess a treatment effect while accounting for longitudinal measures such as patient-reported outcomes. In the Bayesian framework, the deviance information criterion (DIC) and the logarithm of the pseudo-marginal likelihood (LPML) are two well-known Bayesian criteria for comparing joint models. However, these criteria do not provide separate assessments of each component of the joint model. In this article, we develop a novel decomposition of DIC and LPML to assess the fit of the longitudinal and survival components of the joint model, separately. Based on this decomposition, we then propose new Bayesian model assessment criteria, namely, ΔDIC and ΔLPML, to determine the importance and contribution of the longitudinal (survival) data to the model fit of the survival (longitudinal) data. Moreover, we develop an efficient Monte Carlo method for computing the conditional predictive ordinate statistics in the joint modeling setting. A simulation study is conducted to examine the empirical performance of the proposed criteria and the proposed methodology is further applied to a case study in mesothelioma. Supplementary materials for this article are available online.  相似文献   
10.
On drag, Strouhal number and vortex-street structure   总被引:5,自引:0,他引:5  
A phenomenological model for the vortex-shedding process behind bluff cylindrical bodies is proposed. Relationships between Strouhal frequency St, drag coefficient cD, Reynolds number Re and geometric wake parameters are obtained from mass conservation, momentum conservation in the transverse direction and energy considerations. For the first time, Roshko's (Technical Report TN 3169, NACA, US Government Printing Office, Washington DC, 1954) experimental discovery of vortex-street similarity behind different cylinders is analytically derived. In addition, the empirically obtained Strouhal-frequency laws of Roshko (Technical Report TN1191, NACA, US Government Printing Office, Washington DC, 1954) and Fey (Phys. fluids A 10 (1998) 1547) are also reproduced. Measurements of St and cD including their Re dependency for flows around cylinders with circular, square, triangular, semi-circular and other cross sections agree favorably with the proposed model.  相似文献   
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