Brownian zoyenda: mwachidule.

Mu magawo oyambirira a chitukuko cha chiphunzitso cha machitidwe colloidal, ankaganiza kuti maselo katundu kayendedwe wapadera njira woona. maphunziro yaitali anasonyeza kuti katundu awa chibadidwe ndi colloidal njira. Iwo anapeza kuti pakati pawo palibe kusiyana Mkhalidwe, ndipo pali kachulukidwe kokha, kumene amadalira makamaka pa kukula ndi mawonekedwe a particles colloid (micelles). Choncho, kutsegula kwa zoyenda Brownian Mwanjira imeneyi inali yofunika kwambiri.

Kwa nthawi yoyamba (mu 1827), Brownian zoyenda kuphunzira ndi English katswiri Robert Brown. Kusunga ultramicroscope zomera mungu, zizikhala dontho la madzi, wasayansi anapeza kuti particles tosaoneka mungu zoumbika mosiyanasiyana (mosintha) ndi mosalekeza anagwidwa. Brownian zoyenda - ndi mosalongosoka, wachisokonezo kapena yokhotakhota zoyenda wa microparticles. Kafukufuku wosiyanasiyana anakhazikitsa kuti kayendedwe mwachisawawa mamolekyulu amayamba ndi tinthu kukula, kutentha ndi kukhuthala kwa sing'anga kupezeka. Pankhaniyi, chikhalidwe cha thunthu ali pafupifupi ziribe mphamvu pa kayendedwe kawo.

Brownian poyenda ndi amakono maselo-kayendedwe chiphunzitso zakumwa

Frankel adati kusamuka kwa wina molekyulu rearrangement pafupi, omwe amamuchititsa kutenga malo ake loyambirira, lomwe ndi zaphindu kwambiri mawu a mphamvu.

Chifukwa, mosayembekezeka ndi mosalekeza kayendedwe ka kudziona mayamwidwe ndondomeko ya mamolekyulu amapezeka. Kusungunuka mu microparticles madzi (gawo kupezeka) kuchita kayendedwe ndi pafupifupi chimodzimodzi ngati zosungunulira molekyulu (kupezeka sing'anga). Chifukwa wachisokonezo zoyenda mosalekeza amasuntha mwachangu ndipo musakhale mu malo aliwonse.

Brownian zoyenda wa particles ndi suspensions colloidal kumachitika chifukwa matenthedwe zoyenda sing'anga ozungulira particles ndi kumenyedwa awo wachisokonezo kwa molekyu imeneyi. Chifukwa cha zoopsa zotere microparticles mosintha akusuntha mu mlengalenga (kumwazikana sing'anga). magulu awa ndi zotsatira za zochita mantha nthawi zina za phunziroli (mphindi imodzi yeniyeni molekyulu akhoza kukumana mpaka 1020 zikwapu). Popeza kuti kukula ka molekyulu ndi milingo yosiyanasiyana ya nkhonya ku kumathandiza kupeza ngodya zosiyanasiyana, ikuyenda mu madera osiyana. Ndi awiri a micrometres oposa asanu microparticles Brownian zoyenda ali pafupifupi mwaonapo. Kukula kukula ndi kulemera maselo a mantha awo zimatenga. Choncho, particles ndi kulemera mkulu maselo (mpaka micrometers zisanu) ntchito zokhazo rotational kugwedera.

Brownian poyenda ndi mayamwidwe

Chifukwa cha Brownian ndi matenthedwe zoyenda la tinthu amapezeka mayikidwe ndende mu buku njira. Mayamwidwe zichitike mu njira colloidal ndi chenicheni.

Osmotic Anzanu chifukwa cha kukhalapo kwa micelles. Chifukwa chachikulu cha mamolekyulu ndi zazing'ono kuthamanga woipa awo otsika kwambiri. Kumene, kuthamanga mu gawo la njira analyte colloidal kwakukulukulu zimadalira pamaso zosafunika wa electrolytes zosiyanasiyana. Choncho, macromolecular njira - polysaccharides, labala, mapuloteni - pa peresenti 10-12 ndende ndi chidwi osmotic anzawo. Chifukwa cha zipangizo wapadera (osmometry) anatsimikiza kuthamanga osmotic wa madzi a m'magazi, amene ali pafupifupi pafupifupi 25 mamilimita Hg. Iwo imatsimikizirika kuti zoipazi ndi mwachindunji njila kwa anthu ambiri zinthu kusungunuka njira colloidal zoona.