11,939 research outputs found
Estimated shuttle loading emissions
As space shuttle tanks are loaded with N2O4, pressurization gas is displaced and at the same time N2O4 entering the tank evaporates and mixes with the pressurization gas remaining in the tank. Further addition of N2O4 to the tank requires venting of this mixture of N2O4/NO2 vapor and pressurization gas, which must be scrubbed prior to atmospheric release. A computer analysis was performed to estimate concentrations, flow rates, and total quantities vented during the planned fast fill/slow fill cycles of 125 gallon and 640 gallon space shuttle tanks. With helium as the pressurization gas, total vent quantities were estimated to be 4.5 and 24 pounds N2O4, respectively, for the two tank sizes
Linking hematopoietic regeneration to developmental signalingpathways: a story of BMP and Wnt
Neo-Colonial Relationships Gone Wrong: French Leaders Should Be Held Legally Responsible for their Role in the Rwandan Genocide
This article explores the role of outside government intervention in civil war conflicts and the ability of these government actors to be held responsible for crimes committed by association and assistance to war criminals. By using the example of the French/Rwandan relationship and the criminal responsibility that France may have for its association and assistance to the Hutu majority government, it looks to the pitfalls that many western countries could find themselves in by assuming similar roles with other repressive and unstable regimes. This analysis proves particularly timely as lawyers for six Rwandan citizens recently filed a lawsuit with the Army Tribunal of Paris alleging that French soldiers had a role in the 1994 Rwanda genocide. Exploring various contemporary theories of criminal responsibility including complicity and other forms of indirect criminal responsibility, the analysis shows that if the allegations against French officials responsible for Operation Turquoise and the accompanying diplomatic and arms support are true, they could be held criminally liable for their participation in the Rwandan genocide of 1994. Beginning by laying the foundation of the history of the conflict and subsequent genocide as well as the facts surrounding France’s role before and during this conflict, the article sets out a case for the culpability of France. Briefly exploring jurisdictional issues, the analysis moves on to examine three theories of culpability; complicity in genocide, joint criminal enterprise, and command responsibility. Upon making a strong case under each of these international legal theories the paper then compares the Rwandan incident with other incidences of neo-colonialism or imperialism both in past and present times. Finally, the article concludes by stating the need for global accountability in our responsibility to not participate in actions against humanity
Handbook on Hypergolic Propellant Discharges and Disposal
The efficiency of all treatment methods formerly or currently used in treating chemical wastes is assessed with emphasis on the disposal of hypergolic propellants. Maximum focus is on the space shuttle propellants MMH and N2O4. Except for hydrogen peroxide oxidizers, all the propellants are nitrogen based and can be potentially reduced to valuable plant nutrients. In theory, all the propellants can be reduced to carbon, hydrogen, nitrogen, and oxygen, except of fuming nitric acid which contains a small amount of fluorine. Appendices cover: (1) a general design criteria for disposal ponds; (2) thermal aspects of reaction in dilute solution; (3) gas bubble growth, detachment, and rise (4) absorption scrubber fundamentals and descriptions; (5) separation of a propellant vapor from a helium stream by permeation; and (6) atmospheric emission limits
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