We investigated the stability of oxide nano particles in oxide dispersion-strengthened (ODS) steel, which is a promising candidate material for next-generation reactors, under neutron irradiation at ...high temperature to high doses. MA957, a 14Cr-ODS steel, was irradiated with Joyo in Japan Atomic Energy Agency under irradiation conditions of 130 dpa at 502 ºC, 154 dpa at 589 ºC, and 158 dpa at 709 ºC. Three-dimensional atom probe (3D-AP) and transmission electron microscope (TEM) observation were performed to characterize the oxide particles in the ODS steels. A high number density of Y-Ti-O particle was observed in the unirradiated and irradiated samples. Almost no change in the morphology of the oxide particles, i.e. average diameter, number density, and chemical composition, has been observed in the samples irradiated to 130 dpa at 502 ºC and to 154 dpa at 589 ºC. A slight decrease in number density was observed in the sample irradiated to 158 dpa at 709 ºC. The hardness of any of the irradiated samples was almost unchanged from that of the unirradiated sample. It was revealed that the oxide particles existed stable, and the strength of the material was sufficiently maintained even after being neutron irradiated to high dose of ∼160 dpa at high temperature up to 700 ºC.
Atom maps for Yttrium, Titanium and Oxygen in ODS steel before/after neutron irradiation obtained with three-dimensional atom probe. Display omitted
Abstract
In the process of power operation, the correct identification of tools can lay a foundation for the detection of violations in power operation. In order to realize the recognition of power ...instruments, based on the current Yolo V5 algorithm, a detection algorithm for power instruments is proposed by improving Yolo V5 algorithm. Firstly, the model of Yolo V5 algorithm is introduced. Then the establishment of the power tool database and the process of model training are analysed. Finally, the test results are analysed and evaluated. The models generated after training were accelerated by TensorRT and then deployed on Jetson Xavier NX.
For the purpose of utilizing the high voltage of a Geiger-Mueller (GM) tube survey meter for corona electric discharge experiment, the relation between the applied high voltage and corona discharge ...current for the different curvatures of the tips of the electrodes was examined both experimentally and theoretically. As a result, a new electric discharge phenomenon “triggered corona discharge” with the help of the usage of a leaf electroscope and tribo-electricity was found. Performance of science experiment such as corona electric discharge after radiation education experiments using the same GM tube survey meter is an effective use of the equipment and also helpful to understand “ionization phenomenon” from different perspectives of nuclear radiation, electric discharge and tribo-electricity.
Abstract
Astronauts Yuri Gagarin, Gherman Titov and John Glenn, in their satellite flights around the Earth, were first humans who experienced extended period of weightlessness, although with ...different feelings. Soon after these history-making events, various articles appeared in pedagogical journals, proposing classroom demonstrations by which teachers could show to their students weightlessness-related physical phenomena in freely-falling systems. In this article, a new demonstration of free-fall weightlessness is described and illustrated by photos taken from its recorded video. When a charged needle electroscope is at rest, the inclined position of the needle is determined by the equilibrium of moments of repulsive electrostatic force and gravitational force. In free fall, only repulsive electrostatic force acts in electroscope-bounded reference frame, causing visible rotational motion of the needle.
Abstract
Many public schools in Brazil do not have the financial resources to obtain certain equipment for teaching physics. Considering that the Brazilian National Common Curricular Base, a ...normative document that defines the organic and progressive set of essential learning that all students must develop, determines that the curriculum for teaching electromagnetism for high school encompass electrostatics. It is very important that schools offer laboratory conditions. For this reason, it was proposed to design simple and low-cost construction equipment, so that teachers from the basic education network can build them for their schools, thus improving the quality of teaching for their students. This study aims to gather equipment and experiments, such as electroscope, electrophorus, Leyden jar and Van de Graaf generator, which can be used in the classroom for didactic purposes in physics teaching. The main focus of this work is the construction of equipment for the implementation of a laboratory for the study of electrostatics, which addresses physical concepts seen by high school students of the basic network in Brazil.
As the key site in extending the territoriology of Victorian Spiritualism, the domestic séance harboured multiple interstices or interstitial spaces, most notably evident in the spaces in-between ...sitters and mediums, the various particularities of the séance room (such as spirit cabinets and penetrable walls for spirit materialisation and transport), and the thresholds between the world sitters inhabited and the one with which they sought intimate contact. Notions of interstitial space extended into Spiritualist philosophy when Anna Blackwell wrote in 1871 of a proto-quantum mechanics model of inter-cellular connec-tivity, linking humans to spirits that predated twentieth-century quantum notions of entanglement and nonlocality. The introduction of telephony in Britain further expanded the psychical geography of a Spiritualist imaginary of longdistance communication and provided a new means for spirit contact. In addition, the appearance of the telephone silence cabinet, an interstitial communicative device functioning in a manner similar to that of the séance spirit cabinet, provided conversation privacy through the mediumistic assistance of postal employees. This article contends that interstitial space served as a key component of Spiritualist thought and practice furthering an imaginary of social possibility in 1870s Britain.
PDF
