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Green Cement Absorbs Carbon 213

Peace Corps Online writes "Concrete accounts for more than 5 percent of human-caused carbon dioxide emissions annually, mostly because cement, the active ingredient in concrete, is made by baking limestone and clay powders under intense heat that is generally produced by the burning of fossil fuels. Now Scientific American reports that British start-up company Novacem has developed a 'carbon-negative' cement that absorbs more carbon dioxide than it emits over its life cycle. The trick is to make cement from magnesium silicates rather than calcium carbonate, or limestone, since this material does not emit CO2 in manufacture and absorbs the greenhouse gas as it ages. 'The building and construction industry knows it has got to do radical things to reduce its carbon footprint and cement companies understand there is not a lot they can do without a technology breakthrough,' says Novacem Chairman Stuart Evans. Novacem estimates that for every ton of Portland cement replaced by its product, around three-quarters of a ton of CO2 is saved, turning the cement industry from a big emitter to a big absorber of carbon. Major cement makers have been working hard to reduce CO2 emissions by investing in modern kilns and using as little carbon-heavy fuel as possible, but reductions to date have been limited. Novacem has raised $1.7M to start a pilot plant that should be up and running in northern England in 2011."

Comment Re:Why does this matter? (Score 1, Insightful) 590

This comment gets rated 'Insightful'? To me it shows a complete lack of understanding of how media constructed 'norms' over time influence societies norms. The discussion of race and gender representation in computer games is long overdue and is just as valid as such discussions about film and television, perhaps more so seeing how games are played proportionally more by younger people. If you don't think this discussion is valid then IMHO you don't understand the influence of media in creating role-models.

Comment Re:This. Game. Sucks. (Score 1) 138

I agree. I liked this game a lot because of what they were trying to achieve. It is much more ambitious and interesting than something like Crysis. Although the OPs points are valid this is a different type of game - where getting around and knowing where you are are part of the challenge. As much as these things frustrate they also immersed me more in the world of the game. I'd love to see this game with another year of work done on it to really bring the non-linearity and the politics to the fore. I initially played as if i was really the character and made decisions about which factions i would work for based on whose politics i agreed with. It was frustrating to realise that I HAD to do missions for the right wing militia after a while. I would have loved if the story went in different directions based on which factions you supported.

Comment Re:DRM is pointless (Score 4, Insightful) 634

Your notion of 'music' is limited and dated. Touring and music creation are not inextricably linked. Much great music has been made by artists for whom it isn't economically feasible to tour (independant bedroom producers, huge experimental orchestras). Much music is made now for recorded delivery and can not be meaningfully replicated 'live'. Your idea of music 'authenticity' (i.e. bands who can play instruments well on stage) is confusing music and sport. Your ears tell you what is good music or not. Performance is a different skill altogether.

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