Heat transformers reveal significant potential for primary energy savings in domestic and industrial processes, which can use different heat sources as driving force to provide the heat or cooling. In this paper, a hybrid resorption-compression heat transformer is presented, which aims to upgrade the heat source e.g. industrial waste heat or solar energy with a large temperature lift. Performance of hybrid heat transformer is also compared with that of multi-stage sorption type. Results indicate that with heat source temperatures ranging from 40 °C to 90 °C, energy and exergy efficiencies of hybrid heat transformer decrease from 0.429 to 0.403 and from 0.8 to 0.64, respectively. Energy efficiency of hybrid type is a bit lower than that of basic resorption transformer but almost double higher than that of multi-stage cycle. For different operating parameters, mass ratio and global conversion rate have larger influences on thermal performance than isentropic efficiency of compressor. Also hybrid resorption-compression heat transformer is prospective for domestic heat application through the integration with solar photovoltaic thermal collector. When heat output temperature ranges from 50 °C to 70 °C, it could ensure that the heat density is higher than 1000 kJ·kg_am⁻¹ with an energy storage function.

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Nonlinear finite element (FE) collapse pressure predictions are compared to experimental results for submarine pressure hull test specimens with and without artificial corrosion and tested to collapse under external hydrostatic pressure. The accuracy of FE models, and their sensitivity to modeling and solution procedures, are investigated by comparing FE simulations of the experiments using two different model generators and three solvers. The standard FE methodology includes the use of quadrilateral shell elements, nonlinear mapping of measured geometric imperfections, and quasi-static incremental analyses including nonlinear material and geometry. The FE models are found to be accurate to approximately 11%, with 95% confidence, regardless of the model generator and solver that is used. Collapse pressure predictions for identical FE models obtained using each of the three solvers agree within 2.8%, indicating that the choice of FE solver does not significantly affect the predicted collapse pressure. The FE predictions are found to be more accurate for corroded than for undamaged models, and neglecting the shell eccentricity that arises due to one-sided shell thinning is found to significantly decrease the resulting accuracy of the FE model.@en

The drive for elucidation of important macromolecular structures to high resolution in their 3D native or near-native state places continuously higher demands on the quality of the experimental data. For instance, recording of diffraction patterns good enough for structural studies from cryo-preserved bio-macromolecules at low dose conditions remains challenging and highly desirable. The emergence of hybrid pixel detectors opens up new possibilities for direct electron detection and superior detector performance. Here, we report on the characteristics of the Medipix2 detector in diffraction studies, with a special focus on the reliability of the intensities acquired in very low dose conditions. Diffraction data recorded on a Medipix2 detector were assessed in refinement analysis. R-factors lower than 10% were obtained from data recorded at electron dose of 0.05 el/angstrom(2). The reproducibility of the data was also shown to be high, given the correlation coefficient of the intensities being higher than 0.9970. The contrast that could be achieved at very low dose conditions was at least an order of magnitude better than that of image plates, based on a direct comparison.@en