Nhoroondo yemakani earuminiyamu
Magaba esimbi edoro nezvinwiwa ane nhoroondo yemakore anopfuura makumi manomwe. Mukutanga kwema1930, United States yakatanga kugadzira magaba esimbi edoro. Bhodhoro iri rine zvidimbu zvitatu rakagadzirwa nesimbi. Chikamu chepamusoro chemuviri wetangi chakaita sekoni, uye chikamu chepamusoro chakaita sechivharo chebhodhoro chakaita sekorona. Chitarisiko charo hachina kusiyana zvakanyanya nechemabhodhoro egirazi, saka mutsetse wekuzadza mabhodhoro egirazi wakashandiswa kuzadza pakutanga. Zvakatosvika kuma1950 apo mutsetse wakatsaurirwa wekuzadza wakawanikwa. Chivharo chebhodho chakashanduka kuita chimiro chakati sandara pakati pema1950 uye chakagadziriswa kuita chivharo chemhete yearuminiyamu muma1960.
Magaba ezvinwiwa zvearuminiyamu akaonekwa kare kuma1950 ekupedzisira, uye magaba eDWI ane zvidimbu zviviri akabuda zviri pamutemo kuma1960 ekutanga. Kugadzirwa kwemagaba earuminiyamu kuri kukurumidza zvikuru. Pakupera kwezana rino remakore, kushandiswa kwegore negore kwasvika mabhiriyoni anopfuura 180, inova ndiyo mhando huru pane ese magaba esimbi pasi rose (anenge mabhiriyoni 400). Kushandiswa kwearuminiyamu inoshandiswa kugadzira magaba earuminiyamu kuri kukurawo nekukurumidza. Muna 1963, kwaive pedyo ne zero. Muna 1997, kwakasvika matani mamiriyoni 3.6, zvakaenzana ne15% yekushandiswa kwese kwezvinhu zvakasiyana-siyana zvearuminiyamu pasi rose.
Tekinoroji yekugadzira magaba earuminiyamu yagara ichivandudzwa.
Kwemakumi emakore, tekinoroji yekugadzira magaba earuminiyamu yakaramba ichivandudzwa. Huremu hwemagaba earuminiyamu hwakaderedzwa zvakanyanya. Mukutanga kwema1960, huremu hwemagaba earuminiyamu chiuru chimwe nechimwe (kusanganisira muviri wegaba nechivharo) hwakasvika mapaundi makumi mashanu nemashanu (anenge makirogiramu makumi maviri nemashanu), uye pakati pema1970 hwakaderera kusvika pamakirogiramu makumi mana nemana. Makirogiramu), hwakaderedzwa kusvika pamakirogiramu makumi matatu nematatu (15 makirogiramu) mukupera kwema1990, uye ikozvino hwaderedzwa kusvika pasi pemakirogiramu makumi matatu, inova inenge hafu yemakore makumi mana apfuura. Mumakore makumi maviri kubva muna 1975 kusvika muna 1995, huwandu hwemagaba earuminiyamu (12 ounces muhukuru) akagadzirwa nepaundi imwe yearuminiyamu hwakawedzera ne35%. Pamusoro pezvo, zvichienderana nehuwandu hwekambani yeAmerican ALCOA, zvinhu zvealuminium zvaidiwa pamakani ealuminium chiuru chimwe nechimwe zvakaderedzwa kubva pa25.8 pounds muna 1988 kusvika pa22.5 pounds muna 1998 uye zvakazoderedzwa kusvika pa22.3 pounds muna 2000. Makambani ekugadzira makani ekuAmerica akaramba achiita budiriro mumichina yekuvhara uye mamwe matekinoroji, saka ukobvu hwemakani ealuminium muUnited States hwakaderera zvakanyanya, kubva pa0.343 mm muna 1984 kusvika pa0.285 mm muna 1992 uye 0.259 mm muna 1998.
Kufambira mberi kuri nyore mumavharo emagaba ealuminium kuri pachenawo. Ukobvu hwemavharo emagaba ealuminium hwakaderera kubva pa039 mm pakutanga kwema1960 kusvika pa0.36 mm muma1970, kubva pa0.28 mm kusvika pa0.30 mm muna 1980, uye kusvika pa0.24 mm pakati pema1980. Upamhi hwechivharo chemagaba hwakaderedzwawo. Huremu hwemavharo emagaba hwakaramba huchiderera. Muna 1974, huremu hwemagaba ealuminium chiuru hwaive mapaundi gumi nematatu, muna 1980 hwakaderedzwa kusvika mapaundi gumi nemaviri, muna 1984 hwakaderedzwa kusvika mapaundi gumi nerimwe, muna 1986 hwakaderedzwa kusvika mapaundi gumi, uye muna 1990 na1992 hwakaderedzwa kusvika mapaundi mapfumbamwe nemapfumbamwe zvichiteerana. Makirogiramu masere, akadzikiswa kusvika pamakirogiramu matanhatu nehafu muna 2002. Kumhanya kwekugadzira magaba kwavandudzika zvikuru, kubva pa650-1000cpm (paminiti imwe chete) muma1970 kusvika pa1000-1750cpm muma1980 uye anopfuura 2000cpm pari zvino.
Nguva yekutumira: Zvita-28-2021