Synthetic Natural Environment Research Articles

Roles of carbon dioxide and steam on the hydrogen embrittlement of 3Cr tube steel in synthetic natural gas environment

ABSTRACTThe hydrogen embrittlement behaviour of 3Cr has been investigated under mixed H2 with CO2 at different strain rates, hydrogen partial pressures, and in the presence/absence of steam. The slow strain rate test results show that the HE susceptibility of 3Cr increased with increasing hydrogen partial pressure, and the plasticity of 3Cr obviously decreased in the presence of steam. The effect of strain rate was negligible in H2/CO2 environment but showed a significant difference in H2/CO2/steam environment. The fracture was a ductile fracture mode in N2 environment and a brittle fracture mode in H2/CO2/steam environment. The reason for the severe plasticity loss of 3Cr in H2/CO2/steam environment was probably that the steam has a preferential adsorption onto the 3Cr surface compared with H2 and CO2. Consequences in CO2 combined with H2O to form H2CO3, which accelerated the anodic dissolution of 3Cr, and the physical adsorption of H2 on steel was enhanced.

A novel accurate and expandable infrared radiation transmission effect computing service

In infrared imaging simulation system, the infrared radiation transmission is significantly affected by natural environment. Attenuation and blurring are introduced by atmospheric environment impacts on the transmission process from zero sight infrared radiation to the detector. The classic IR transmission calculation methods have been intensively studied and many applicable approaches are proposed. The novel IR transmission effect computing service introduced in this paper could render accurate and expandable IR simulation result based on synthetic natural environment, especially concerning the atmosphere effects imposed on the IR transmission process. A simulation architecture is constructed and supports an infrared imaging simulation system for the IR transmission process calculation. The environment representation approach and the transmission effect calculation method were elaborated. Simulation experiment was carried out and the result was shown to be more accurate than that of conventional MODTRAN based atmosphere transmission simulation results. The two results are both compared with the physically captured image. The comprehensive simulation experiment results are implied to be competent and offered an applicable solution for the infrared imaging simulation system. Furthermore, this interdisciplinary simulation method can be extended to other synthetic natural environment supported military simulation and further serve the large-scale distributed collaborative combat simulation.

Environmental cues used by advanced practice nurses in air medical services

Environmental cues used by advanced practice nurses in air medical services