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The problem of developing a dedicated neutron diffractometer for placement on a horizontal reactor channel to measure internal stresses in bulk materials and components under conditions of a limited space is considered. It is shown that the use of a double-crystal monochromator composed of pyrolytic graphite and a focusing bent perfect silicon single crystal is the optimal solution to this problem. The diffractometer with such a monochromator that is installed at the IR-8 reactor of the National Research Center Kurchatov Institute is comparable in luminosity and resolution at a reactor power of 6 MW to modern stress diffractometers at more powerful reactors.  相似文献   
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Robotics has been a very fast growing field especially in the last years. In the late 1970s the first industrial applications of stationary unintelligent industrial robots were realised. Since the beginning of the 1990s a new generation of mobile, intelligent, cooperative robots has grown up. This new generation opens new applications areas, e.g. in production automation, in agriculture, in the food industry, in household, for medical and rehabilitation applications, in the entertainment industry as well as for leisure and hobby. Current developing trends are humanoid robots and robots supporting people in everyday life. Other intensive research areas are cooperative robots, bio inspired robots, ubiquitous robots and cloud robots. The following paper is divided into three parts: current state, future development trends as well as visions in robotics.  相似文献   
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Electrostatic or capacitive accelerometers are among the highest volume microelectromechanical systems (MEMS) products nowadays. The design of such devices is a complex task, since they depend on many performance requirements, which are often conflicting. Therefore, optimization techniques are often used in the design stage of these MEMS devices. Because of problems with reliability, the technology of MEMS is not yet well established. Thus, in this work, size optimization is combined with the reliability-based design optimization (RBDO) method to improve the performance of accelerometers. To account for uncertainties in the dimensions and material properties of these devices, the first order reliability method is applied to calculate the probabilities involved in the RBDO formulation. Practical examples of bulk-type capacitive accelerometer designs are presented and discussed to evaluate the potential of the implemented RBDO solver.  相似文献   
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The true boiling point curve (TBP) is an important tool for the petroleum industry; it is used to obtain the behavior of petroleum during distillation. This work developed a correlation for the extension of the TBP curve by means of molecular distillation. TBP curve is well established for a temperature of 565°C in a conventional distillation. With the correlation developed, it is possible to reach values near 1,000°C. A second correlation was also developed for predicting the values of molar mass of waste petroleum. Both correlations demonstrated to be valid and represent a great advancement for the petroleum industry.  相似文献   
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Mastitis is a major challenge to bovine health. The detection of sensitive markers for mastitis in dairy herds is of great demand. Suitable biomarkers should be measurable in milk and should report pathogen-specific changes at an early stage to support earlier diagnosis and more efficient treatment. However, the identification of sensitive biomarkers in milk has remained a challenge, in part due to their relatively low concentration in milk. In the present study, we used a selected reaction monitoring (SRM) mass spectrometry approach, which allowed the absolute quantitation of 13 host response proteins in milk for the first time. These proteins were measured over a 54-h period upon an in vivo challenge with cell wall components from either gram-negative (lipopolysaccharide from Escherichia coli; LPS) or gram-positive bacteria (peptidoglycan from Staphylococcus aureus; PGN). Whereas our data clearly demonstrate that all challenged animals have consistent upregulation of innate immune response proteins after both LPS and PGN challenge, the data also reveal clearly that LPS challenge unleashes faster and shows a more intense host response compared with PGN challenge. Biomarker candidates that may distinguish between gram-negative and gram-positive bacteria include α-2 macroglobulin, α-1 antitrypsin, haptoglobin, serum amyloid A3, cluster of differentiation 14, calgranulin B, cathepsin C, vanin-1, galectin 1, galectin 3, and IL-8. Our approach can support further studies of large cohorts of animals with natural occurring mastitis, to validate the relevance of these suggested biomarkers in dairy production.  相似文献   
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High-purity semi-insulating 8° off-axis 〈0001〉 4H-SiC was implanted with Al+ at different doses and energies to obtain a dopant concentration in the range of 5 × 1019–5 × 1020 cm?3. A custom-made microwave heating system was employed for post-implantation annealing at 2,000 °C for 30 s. Sheet resistance and Hall-effect measurements were performed in the temperature range of 150–700 K. At room temperature, for the highest Al concentration, a minimum resistivity of 3 × 10?2 Ω cm was obtained, whereas for the lowest Al concentration, the measured resistivity value was 4 × 10?1 Ω cm. The onset of impurity band conduction was observed at around room temperature for the samples implanted with Al concentrations ≥3 × 1020 cm?3. Vertical p +-i-n diodes whose anodes were made by 1.5 × 1020 cm?3 Al+ implantation and 2,000 °C/30 s microwave annealing showed exponential forward current–voltage characteristics with two different ideality factors under low current injection. A crossover point of the temperature coefficient of the diode resistance, from negative to positive values, was observed when the forward current entered the ohmic regime.  相似文献   
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