Kodi mukukumbukira melamine? Ndiwodziwika bwino kwambiri "wowonjezera ufa wa mkaka", koma chodabwitsa, ukhoza "kusinthidwa".

Pa February 2, pepala lofufuzira linasindikizidwa mu Nature, nyuzipepala ya sayansi yapadziko lonse lapansi, ponena kuti melamine ikhoza kupangidwa kukhala chinthu cholimba kwambiri kuposa chitsulo komanso chopepuka kuposa pulasitiki, modabwitsa anthu. Pepalali lidasindikizidwa ndi gulu lotsogozedwa ndi wasayansi wodziwika bwino wazinthu Michael Strano, pulofesa mu dipatimenti ya Chemical Engineering ku Massachusetts Institute of Technology, ndipo wolemba woyamba anali mnzake wa postdoctoral Yuwei Zeng.

Akuti adatchula dzina lamaterial muwotuluka kuchokera ku melamine 2DPA-1, polima wa mbali ziwiri yemwe amadziphatikiza pamasamba kuti apange zinthu zocheperako koma zolimba kwambiri, zapamwamba kwambiri, zomwe ma patent awiri adasungidwira.

Melamine, yomwe imadziwika kuti dimethylamine, ndi galasi loyera la monoclinic lomwe limawoneka ngati mkaka p

Melamine ndi yopanda pake ndipo imasungunuka pang'ono m'madzi, komanso mu methanol, formaldehyde, acetic acid, glycerin, pyridine, ndi zina zotero. Isungunuka mu acetone ndi ether. Ndizovulaza thupi la munthu, ndipo onse a China ndi WHO adanena kuti melamine sayenera kugwiritsidwa ntchito pokonza chakudya kapena zowonjezera zakudya, koma kwenikweni melamine ndi yofunika kwambiri ngati mankhwala opangira mankhwala ndi zomangamanga, makamaka mu utoto, lacquers, mbale, zomatira ndi zinthu zina zambiri ntchito.

Maselo a melamine ndi C3H6N6 ndipo kulemera kwa molekyulu ndi 126.12. Kupyolera mu mankhwala chilinganizo ake, tingathe kudziwa kuti melamine lili zinthu zitatu, carbon, haidrojeni ndi nayitrogeni, ndipo lili ndi dongosolo mpweya ndi nayitrogeni mphete, ndi asayansi MIT anapeza mu zoyeserera zawo kuti melamine mamolekyu monomers akhoza kukula pa miyeso iwiri pansi yoyenera. mikhalidwe, ndipo zomangira za haidrojeni mu mamolekyu zidzakhazikika palimodzi, kuzipanga mosalekeza Zomangira za haidrojeni mu mamolekyu zidzakhazikika palimodzi, kuzipanga kukhala mawonekedwe a diski mosalekeza, basi. monga mawonekedwe a hexagonal opangidwa ndi ma graphene awiri-dimensional, ndipo kapangidwe kameneka kamakhala kokhazikika komanso kolimba, kotero melamine imasandulika kukhala pepala lapamwamba kwambiri lotchedwa polyamide m'manja mwa asayansi.

Zinthuzi ndizosavuta kupanga, adatero Strano, ndipo zitha kupangidwa zokha mu yankho, momwe filimu ya 2DPA-1 imatha kuchotsedwa, ndikupereka njira yosavuta yopangira zinthu zolimba kwambiri koma zoonda kwambiri.

Ofufuzawo anapeza kuti zinthu zatsopanozi zili ndi mphamvu yopunthira, yomwe ndi yochuluka kuwirikiza kanayi kapena sikisi kuposa ya magalasi oletsa zipolopolo. Anapezanso kuti ngakhale kuti gawo limodzi mwa magawo asanu ndi limodzi ndi lolimba ngati chitsulo, polima ili ndi mphamvu zokolola kawiri, kapena mphamvu yofunikira kuti iwononge zinthuzo.

Chinthu chinanso chofunika kwambiri cha zinthuzo ndi kupuma kwake. Pomwe ma polima ena amakhala ndi maunyolo opotoka okhala ndi mipata pomwe mpweya ungatuluke, zatsopanozi zimakhala ndi ma monomers omwe amamatira limodzi ngati midadada ya Lego ndipo mamolekyu sangalowe pakati pawo.

Izi zimatipatsa mwayi wopanga zokutira zoonda kwambiri zomwe sizingalowe m'madzi kapena gasi, "adatero asayansi. Zotchingira zotchinga zamtunduwu zitha kugwiritsidwa ntchito kuteteza zitsulo zamagalimoto ndi magalimoto ena kapena zitsulo. ”

Tsopano ochita kafukufuku akuphunzira momwe polima iyi ingapangidwe kukhala mapepala amitundu iwiri mwatsatanetsatane ndipo akuyesera kusintha mamolekyu ake kuti apange mitundu ina ya zipangizo zatsopano.

Zikuwonekeratu kuti zinthuzi ndi zofunika kwambiri, ndipo ngati zingatheke kupangidwa mochuluka, zikhoza kubweretsa kusintha kwakukulu kumalo otetezera magalimoto, ndege, ndi mpira. Makamaka pamagalimoto amagetsi atsopano, ngakhale kuti mayiko ambiri akukonzekera kuchotsa magalimoto oyendetsa mafuta pambuyo pa 2035, koma magalimoto atsopano amphamvu adakalibe vuto. Ngati zinthu zatsopanozi zitha kugwiritsidwa ntchito pamagalimoto, zikutanthauza kuti kulemera kwa magalimoto atsopano amphamvu kudzachepetsedwa kwambiri, komanso kuchepetsa kuchepa kwa mphamvu, zomwe zidzasintha mosadukiza kuchuluka kwa magalimoto atsopano amagetsi.