{"id":9049,"date":"2011-06-27T03:00:59","date_gmt":"2011-06-27T08:00:59","guid":{"rendered":"http:\/\/blogs.scienceforums.net\/swansont\/?p=9049"},"modified":"2011-06-27T03:00:59","modified_gmt":"2011-06-27T08:00:59","slug":"we-are-saved-again","status":"publish","type":"post","link":"http:\/\/blogs.scienceforums.net\/swansont\/archives\/9049","title":{"rendered":"We Are Saved! Again!"},"content":{"rendered":"

New Alloy Can Convert Heat Directly Into Electricity<\/a><\/p>\n

[T]he new alloy \u2014 Ni45Co5Mn40Sn10 \u2014 undergoes a reversible phase transformation, in which one type of solid turns into another type of solid when the temperature changes, according to a news release from the University of Minnesota. Specifically, the alloy goes from being non-magnetic to highly magnetized. The temperature only needs to be raised a small amount for this to happen.<\/p><\/blockquote>\n

But if it’s a phase transformation, it should be happening at a specific temperature. Once the material has heated up and you get your magnetic field, what then? The article and press release<\/a> on which it was based don’t go into that.<\/p>\n

During a small-scale demonstration in a University of Minnesota lab, the new material created by the researchers begins as a non-magnetic material, then suddenly becomes strongly magnetic when the temperature is raised a small amount. When this happens, the material absorbs heat and spontaneously produces electricity in a surrounding coil.<\/p><\/blockquote>\n

Faraday’s law tells us this should happen upon the creation of the magnetic field, but once it has happened \u2014 nada. You would need to cycle between states to maintain a changing field needed to continually produce electricity, so after heating you would need to then cool the substance.<\/p>\n

The paper<\/a> confirms this requirement<\/p>\n

The design of the coil is to give a maximal component of E parallel to the wire, thereby driving a current. A potential difference across the coil of opposite polarity is obtained on the reverse phase transformation upon cooling.<\/p><\/blockquote>\n

So here “directly” doesn’t mean “directly” in the sense that you slap it on a car engine and produce electricity. You need a temperature gradient, just like always, and in this case, you need to bracket a specific temperature. Promising, but these headlines always seem to outnumber new products by a fair margin.<\/p>\n","protected":false},"excerpt":{"rendered":"

New Alloy Can Convert Heat Directly Into Electricity [T]he new alloy \u2014 Ni45Co5Mn40Sn10 \u2014 undergoes a reversible phase transformation, in which one type of solid turns into another type of solid when the temperature changes, according to a news release … Continue reading →<\/span><\/a><\/p>\n","protected":false},"author":2,"featured_media":0,"comment_status":"open","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[39,53],"tags":[],"class_list":["post-9049","post","type-post","status-publish","format-standard","hentry","category-physics","category-tech"],"_links":{"self":[{"href":"http:\/\/blogs.scienceforums.net\/swansont\/wp-json\/wp\/v2\/posts\/9049","targetHints":{"allow":["GET"]}}],"collection":[{"href":"http:\/\/blogs.scienceforums.net\/swansont\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"http:\/\/blogs.scienceforums.net\/swansont\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"http:\/\/blogs.scienceforums.net\/swansont\/wp-json\/wp\/v2\/users\/2"}],"replies":[{"embeddable":true,"href":"http:\/\/blogs.scienceforums.net\/swansont\/wp-json\/wp\/v2\/comments?post=9049"}],"version-history":[{"count":0,"href":"http:\/\/blogs.scienceforums.net\/swansont\/wp-json\/wp\/v2\/posts\/9049\/revisions"}],"wp:attachment":[{"href":"http:\/\/blogs.scienceforums.net\/swansont\/wp-json\/wp\/v2\/media?parent=9049"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"http:\/\/blogs.scienceforums.net\/swansont\/wp-json\/wp\/v2\/categories?post=9049"},{"taxonomy":"post_tag","embeddable":true,"href":"http:\/\/blogs.scienceforums.net\/swansont\/wp-json\/wp\/v2\/tags?post=9049"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}