Topic
Shields
About: Shields is a research topic. Over the lifetime, 1456 publications have been published within this topic receiving 10896 citations.
Papers published on a yearly basis
Papers
More filters
TL;DR: In this paper , Monte Carlo simulations to assess the performance of different materials (polyethylene, aluminum, Moon regolith) as thick shields (up to 400 g/cm2) against GCR were conducted using the FLUKA code.
Abstract: The exposure to galactic cosmic radiation (GCR) is a major health concern for astronauts. Crewed missions with durations of several years are foreseen in future space exploration projects such as permanent habitats on the Moon and flights to Mars. This aim requires elaborate space radiation shielding concepts and a proper understanding of the underlying radiation physics and radiobiology as well as their interplay. In the present work, Monte Carlo simulations to assess the performance of different materials (polyethylene, aluminum, Moon regolith) as thick shields (up to 400 g/cm2) against GCR were conducted using the FLUKA code. Absorbed dose, dose equivalent and the mean quality factor at 1 cm depth in the ICRU sphere as a function of shielding thickness were calculated in a spherical shell configuration for both solar minimum and solar maximum GCR conditions. Large differences were observed in the performance of the studied materials as thick GCR shields. Special attention was paid to the build-up and moderation of secondary neutrons. A method to reduce the neutron contributions to ambient dose equivalent by means of a two-layer shielding combination is proposed. The present study can be useful for considerations on thick shielding of Moon or Mars habitats built from local regolith.
8 citations
TL;DR: In this paper, the authors used the method of discrete ordinates to calculate the dose equivalent as a function of radius in spherical shields of various compositions, including soil, concrete, ilmenite, iron, and soil.
Abstract: Neutron-transport calculations have been carried out using the method of discrete ordinates, and the dose equivalent as a function of radius in spherical shields of various compositions is presented. The incident-neutron spectra used are characteristic of the spectra emitted in the argular intervals of 0 to 30 deg , 30 to 60 deg , 60 to 120 deg , and 120 to l80 deg when 400-MeV electrons are incident on a thick copper target. Results are given for shields of soil, concrete, ilmenite, iron, and iron followed by soil. (auth)
8 citations
Patent•
[...]
02 Feb 1937
TL;DR: In this paper, the authors proposed a method to add moisture to the air emitted from the air register with which the shield is used, by using a hood or a cover over the shield.
Abstract: The present invention relates to shields or hoods for deflecting the air delivered by warm air registers and more specifically relates to the provision of means to be used in conjunction with such shields for adding moisture to the air emitted from the register with which the shield is used....
8 citations
TL;DR: In this article, a small, rugged glass Dewar using a liquid nitrogen cooled metal shield is described, which is relatively inexpensive to construct and to modify, stores helium with only a moderate loss rate, and can be adapted for a wide variety of low temperature experiments.
Abstract: A small, rugged glass Dewar using a liquid nitrogen cooled metal shield is described. This Dewar is relatively inexpensive to construct and to modify, stores helium with only a moderate loss rate, and can be adapted for a wide variety of low temperature experiments. Two other Dewars, in which vapor‐cooled radiation shields replace liquid nitrogen cooled shields, also are described. Helium loss rates show that a liter of liquid helium will keep these Dewars at 4°K for about 5 to 10 hr.
8 citations