Video: Thaum twg cov hnab ntim khoom ntim tau tsim?
2024 Tus sau: Stanley Ellington | [email protected]. Kawg hloov kho: 2023-12-16 00:17
Los ntawm Xyoo 1960s ntawm, lub tuam txhab tau ua raws li txoj cai nruj ntawm polyethylene ntim patents thiab los ntawm 1977 tau tsim nws lub hnab. Cov hnab yas khoom noj khoom haus tau qhia hauv Asmeskas xyoo 1979; Kroger thiab Safeway tau khaws lawv hauv xyoo 1982. Tab sis qee lub khw muag khoom tau siv lawv.
Tsis tas li lo lus nug yog, thaum twg cov hnab yas ntshiab tau tsim?
Polyethylene (hom feem ntau ntawm yas siv rau pov tseg hnab ) yog thawj zaug tsim nyob rau hauv 1898 tab sis nws tsis yog mus txog rau thaum nruab nrab xyoo 1950s uas muaj polyethylene high-density. invented.
Ib tug kuj nug, thaum twg peb pib siv yas? Thawj yas Raws li ib tug hluavtaws polymer yog tsim los ntawm phenol thiab formaldehyde, nrog thawj txoj kev siv tau yooj yim thiab pheej yig tau tsim nyob rau xyoo 1907, los ntawm Leo HendrikBaekeland, tus neeg Belgian-yug Asmeskas nyob hauv New Yorkstate.
Ib tug kuj nug, thaum twg yog lub hnab yas siv thawj zaug?
Qhov feem ntau yas hauv tam sim no siv ispolyethylene los yog polythene, ua los ntawm petrochemicalethylene. Txawm tias ua ntej tsim los ntawm kev sib tsoo hauv xyoo 1898 los ntawm German chemist Hans von Pechmann, nws tsis yog txog rau xyoo 1950 uas peb lees paub niaj hnub no. yas tau tsim txaus rau kev lag luam thiab pheej yig ntau lawm.
Lawv siv dab tsi ua ntej lub hnab khib nyiab?
Tsev neeg khib nyiab tau khaws cia rau hauv lub nroog-tsim metalcans, sau txhua lub lim tiam los ntawm cov neeg ua haujlwm huv. Ntau tus neeg pov khib nyiab ncaj qha rau hauv lub kaus poom; lwm tus siv ntawv hnab los yog daim ntawv liners, uas sai sai tau ntub thiab sloppy. In 1950, Canadian inventors Harry Wasylyk thiab Larry Hansen invented the hnab khib nyiab.
Pom zoo:
Txoj cai twg tau dhau los hauv xyoo 1972 los tiv thaiv cov neeg siv khoom los ntawm cov khoom tsim kev puas tsuaj?
Consumer Product Safety Act (CPSA) Enacted in 1972, CPSA is our umbrella statute. Txoj cai lij choj no tsim lub koom haum, txhais CPSC txoj cai tseem ceeb thiab tso cai rau lub koom haum los tsim cov qauv thiab txwv. Nws tseem muab CPSC txoj cai los nrhiav kev rov qab thiab txwv cov khoom lag luam raws li qee qhov xwm txheej
Dab tsi yog cov tswv yim thiab cov khoom tsim tawm hauv cov txheej txheem tsim khoom?
Hauv kev lag luam, yam tseem ceeb ntawm kev tsim khoom, peev txheej, lossis cov tswv yim yog qhov uas siv hauv cov txheej txheem tsim khoom los tsim cov khoom tawm - uas yog, cov khoom tiav thiab cov kev pabcuam. Tus nqi siv ntawm ntau yam inputs txiav txim seb qhov ntau npaum li cas ntawm cov zis raws li kev sib raug zoo hu ua ntau lawm muaj nuj nqi
Dab tsi yog qhov kev sib raug zoo ntawm tag nrho cov khoom tsim tau thiab cov khoom tsim tawm thawj zaug sau qhov sib npaug?
Koj tuaj yeem pom tias koj tus lej nyiaj hauv tuam txhab nyiaj tau txiav txim siab raws li hauv qab no: Koj qhov Net ntau lawm yog sib npaug rau koj qhov Kev Tsim Nyog Tag Nrho Tshem Tawm Tawm, uas yog tib yam li qhov sib npaug saum toj no uas hais txog Net Primary Production (NPP) = Gross Primary Production (GPP) Kev ua pa tawm (R)
Thaum twg tus neeg yuav khoom tau txais tswv cuab los ntawm tus muag khoom thaum siv cov lus FOB?
'FOB shipping point' lossis 'FOB keeb kwm' txhais tau tias tus neeg yuav khoom muaj kev pheej hmoo thiab siv cov tswv cuab ntawm cov khoom thaum tus muag khoom xa khoom. Rau cov hom phiaj kev lag luam, tus neeg muag khoom yuav tsum sau ib qho muag ntawm qhov chaw tawm ntawm nws qhov chaw xa khoom
Thaum twg yuav tsum tau tsim pob khoom tsim?
Kev Pabcuam Design Package - (Service Design) Cov ntaub ntawv qhia txog txhua yam ntawm Kev Pabcuam IT thiab lawv Cov Kev Xav Tau los ntawm txhua theem ntawm nws lub neej. Kev Pabcuam Tsim Pob yog tsim rau txhua qhov kev pabcuam IT tshiab, Hloov loj lossis IT Service so haujlwm