Ososayensi benze inzwa eshibhile besebenzisa ubuchwepheshe be-PEGS obungahlola ukudla ubusha futhi kungasiza ukunciphisa ukumoshakala ngenxa yokulahla ukudla ngaphambi kwesikhathi (ukulahla ukudla ngenxa yokuthi kuseduze (noma kudlule) nedethi yokusetshenziswa, kungakhathaliseki ubusha bakho bangempela). Izinzwa zingahlanganiswa emaphaketheni okudla noma kumathegi.
Cishe amaphesenti angu-30 ukudla okuphephile ukuthi kungadliwa abantu kuyalahlwa noma kumane kulahlwe minyaka yonke. Igalelo elikhulu kulokhu okukhulu ukumoshakala kokudla kungenxa yokulahla okwenziwa umthengi noma izitolo ezinkulu ikakhulukazi emazweni athuthukile. Ukudla ukumoshakala sekuba udaba lomhlaba wonke futhi kunomthelela omkhulu emnothweni nakwezemvelo.
Konke kupakishiwe ukudla ethengiswa ezitolo nezitolo ezinkulu inelebula elithi 'use by date' elibonisa usuku lapho ukudla kuphephile futhi kungadliwa. Kodwa-ke, ochwepheshe bathi lolu suku oluvame ukunyatheliswa umenzi luwukulinganisa nje hhayi inkomba enembile yobusha bangempela njengoba ezinye izici isibonelo izimo okugcinwa kuzo ukudla nazo zibalulekile. Ukulahla ukudla ngaphambi kwesikhathi ngesisekelo 'sokusetshenziswa ngedethi' kungakhathaliseki ubusha bakho bangempela kunomthelela emalini enkulu yokumoshwa kokudla minyaka yonke.
Ukusetshenziswa kwezinzwa kungenye indlela ethembisayo 'yokusetshenziswa ngedethi' yomkhiqizi njengoba lezi zinzwa zingakwazi ukulandelela isimo sokubola okupakishweyo okonakalayo futhi zikudlulisele kumsebenzisi ngesikhathi sangempela. Izinhlobo eziningi zobuchwepheshe bezinzwa zenzelwe; kodwa-ke, azikakahlanganiswa nokupakishwa kokudla okujwayelekile ngenxa yezizathu ezimbalwa njengokungasebenzeki kwezohwebo, izindleko eziphezulu, inqubo yokwenziwa eyinkimbinkimbi nobunzima bokusebenzisa. Futhi, lobu buchwepheshe bebungahambisani nezinkundla zedijithali ngakho-ke idatha ayikwazi ukuqondwa kalula ngumsebenzisi.
Ucwaningo olusha olushicilelwe ngoMeyi 8 ngo Izicabisho ze-ACS ichaza isibonelo esizwelayo, esivumelana nemvelo, esibiza kancane futhi esivumelana nezimo se-PEGS (inzwa yegesi kagesi esekelwe ephepheni) ekwazi ukubona amagesi awonakele njenge-ammonia ne-trimethylamine engancibilika emanzini. Inzwa yenziwe ngokuphrinta ama-electrode ekhabhoni ephepheni le-cellulose elitholakala kalula kusetshenziswa ipeni lokukhomba elilula kanye ne-automated cutter plotter. Iphepha le-cellulose, nakuba libukeka lomile, liqukethe imicu ye-cellulose ene-hygroscopic equkethe umswakama okhangeka ebusweni bawo uvela endaweni yangaphandle. Ngakho-ke, izindlela zamakhemikhali ezimanzi zingasetshenziswa ukuzwa amagesi ancibilikayo emanzini ngenxa yalesi sakhiwo se-hygroscopic futhi ngaphandle kokwengezwa kwamanzi ku-substrate. Ukuqhutshwa kwephepha kungalinganiswa ngokusebenzisa ama-electrode amabili ekhabhoni (graphite) aphrintwe phezu kwephepha. Ngakho, ifilimu elincanyana lezinto zikagesi zamanzi lingaphenywa kalula nge-conductance. Uma noma iyiphi igesi encibilikayo emanzini ikhona endaweni eqondile, lokhu kuholela ekwenyukeni kokwenziwa kwe-ionic kwephepha ikakhulukazi ngenxa yokuhlukaniswa kwamagesi ancibilika emanzini kufilimu elincanyana lamanzi phezu kwephepha.
Abacwaningi bahlole ubuchwepheshe be-PEGS ekudleni okupakishiwe (imikhiqizo yenyama - ikakhulukazi inhlanzi nenkukhu) elabhorethri ukuze baqaphe ubusha. Imiphumela yabonisa ukuthi inzwa ye-PEGS ibonise ukuzwela okukhulu kumagesi ancibilikayo emanzini njengoba ikwazile ukuthola ngokushesha nangokunembile ukulandelela amanani amagesi okonakalisayo uma kuqhathaniswa nezinzwa ezikhona. Amagesi ahloliwe kwakuyi-carbon monoxide, carbon dioxide, sulfur dioxide, trimethylamine kanye ne-ammonia ezwela kakhulu i-ammonia ngenxa yokuthi inyibilika kakhulu emanzini. I-PEGS ibonise ukusebenza okuthuthukisiwe, isikhathi sokuphendula esingcono kanye nokuzwela okuphezulu. Futhi, kwakungekho ukushisisa okwengeziwe noma ukukhiqiza okuyinkimbinkimbi okwakudingeka. Le miphumela yaqinisekiswa kusetshenziswa ukuhlolwa okusungulwe kwe-microbiological esebenzisa amasiko amagciwane. Ngakho-ke, i-PEGS ifaneleka njengenkomba yokuhluka kokusha kokudla ngenxa yokungcoliswa kwamagciwane enyameni epakishiwe. Ngaphezu kwalokho, idizayini yenzwa ihlanganiswe nochungechunge lwama-microchips abizwa nge-NFC (near field communication) omaka ukuze kunikwe amandla ukuthatha ukufundwa kumadivayisi eselula aseduze ngaphandle kwentambo.
Inzwa eyingqayizivele echazwe ocwaningweni lwamanje iyinzwa yokuqala ekwazi ukuhwebelana, engenabuthi, ne-eco-friendly engasetshenziswa ukuhlola ubusha bezinto zokudla ngokuthepha ukuzwela kwazo kumagesi abandakanyeka ekuboleni kokudla. Okubalulekile, akubizi, ngenani elincane nje lezindleko zezinzwa ezikhona. I-PEGS isebenza kahle ekamelweni lokushisa ngisho nakumaphesenti angu-100 izimo ezinomswakama ngenkathi idla amandla amancane kakhulu. Ngokusho kwababhali, i-PEGS ingatholakala ukuze ihlanganiswe nokupakishwa kokudla okuthengiswayo ngabakhiqizi nezitolo ezinkulu eminyakeni emi-3 ezayo. Ukusetshenziswa kwazo kunganwetshwa nakwezinye izinhlelo zamakhemikhali nezokwelapha, ezokulima nezemvelo.
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{Ungafunda iphepha lokuqala locwaningo ngokuchofoza isixhumanisi se-DOI esinikezwe ngezansi ohlwini lwemithombo ekhonjiwe}
Umthombo (s)
Barandun G et al. 2019. Imicu yeCellulose inika amandla inzwa kagesi engabizi kakhulu yamagesi ancibilika emanzini. Izinzwa ze-ACS. https://doi.org/10.1021/acssensors.9b00555
