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Mons Rümker, located in the northern part of the near side of the moon, was chosen as the landing site for the future Chinese mission Chang'e-5. The launch of the mission is planned for the end of 2020. This will be the first Chinese mission in which it is planned to return to Earth and deliver samples of lunar soil. The probe will consist of two parts: orbital and landing modules. The landing module will be equipped with a drilling rig capable of taking soil samples from a depth of up to 2 meters. In this paper, we studied the temperature regime and surface characteristics in the region of Mons Rümker. Mons Rümker is located in the northern part of the Oceanus Procellarum. The peak is of volcanic origin. The formation of the peak began in the Imbrian period and ended in the Eratosthenian, that is, its age exceeds 1.3 billion years. We investigated illumination and temperature conditions in the region of the peak. Selected part of the lunar surface is divided into a number of elements of given size. The height, slope and orientation of each element are calculated based on a DEM. To determine the position of the sun at each time step its angular height and the orientation will be calculated. This will allow us to investigate the insolation and solar and infrared flux from all elements of the surface visible from the element at a given time step. The peak height reaches 1.2 km above the surrounding area. The size of the base is about 75 km. The highest part of the feature is located in its southern part. The values of surface slopes range from 0.1 on the surrounding peak area to 9 degrees in the region of the southwestern slope of the peak. Slopes are in the range of 0.3 - 4 degrees in the central part of the peak. The maximum temperatures reach 359 K in this region, and the minimum - about 100 K. [ABSTRACT FROM AUTHOR]

This paper reports the detection and measurement of neutron-induced isotopes in the vault wall of the CS-30 cyclotron located at King Faisal Specialist Hospital and Research Centre (KFSHRC). The aim was to avoid the harmful effects of radiation on employees working with the cyclotron and on faculty members and students using it for nuclear physics research and industrial applications. In addition, emitted radioactivity values are essential in future experiments, as background levels to be subtracted from collected data. Detection was performed using a portable gamma ray spectroscopy system consisting of a NaI(Tl) detector (CANBERRA, model: 802-4) coupled with a digitizer (CAEN, model: N6730) at a counting time of 10 minutes for each point on the wall. The points were at the orientation of 0° with respect to the incoming proton beams and all at 1.5 m above the floor. The results indicate that Co-60, Co-56, Mn-56, Fe-53 are the major radionuclides contributing to the gamma radiation emitted from the wall of cyclotron vault. The link between these isotopes and their corresponding elements was established using the branching index technique. It was found that some isotopes detected were the daughters of elements constituting a very small proportion of the concrete structure such as iron (0.50%), while the elements representing the bulk of the concrete showed no radioactivity. No other significant radioactive sources were detected in the wall. The maximum exposure measured on the wall surface was much less than the permissible occupational exposure for radiation workers. [ABSTRACT FROM AUTHOR]

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Local hemodynamic factors are known affect the natural history of the restenosis critically after coronary stenting of atherosclerosis. Stent-induced flows disturbance magnitude dependent directly on the strut design. The impact of flow alterations around struts vary as the strut geometrical parameters change. Our results provide data regarding the hemodynamic parameters for the blood flow in both stenosed and stented coronary artery under physiological conditions, namely wall shear stress and pressure drop. [ABSTRACT FROM AUTHOR]

This paper reviews the current understanding of powder mixed electrical discharge machining (PMEDM), highlighting particularly the mechanisms proposed for PMEDM under the influence of additive of powders in the dielectric fluids. Generally, the mirror surface phenomenon in PMEDM can be explained by the enlarged gap widths which can expand the discharge channel and thereby reduce the electrical power density since lower power density can yield large and shallow craters that evenly distributed on the machined surface. Moreover, the increment of the inter electrodes distance will limit the capacitive effect and enable a small surface roughness even in a large area. Another possible mechanism, multi-discharge model was also presented in this paper. More investigations on the fundamental mechanism in power mixed EDM are highly desirable since it has not been understood clearly. In this paper, the traditional and some recent development technology for PMEDM is also reviewed. Historically, PMEDM was invented to improve the surface quality of the machined components. Nowadays, some new applications of this technology, such as micro machining, rough machining and surface modification were proposed; some novel variations that based on power mixed EDM, such as PMEDM combined with ultrasonic or abrasive, powder mixed near-dry EDM and powder mixed electrical chemical discharge machining (ECDM) were also developed. [ABSTRACT FROM PUBLISHER]