2024 Tus sau: Elizabeth Oswald | [email protected]. Kawg hloov kho: 2024-01-13 00:07
1. Cov neeg ua haujlwm hauv kev lag luam qhuav-tu. Trichlorethylene tau siv rau hauv kev tu kom qhuav ua cov kuab tshuaj tseem ceeb (los ntawm xyoo 1930 mus txog rau xyoo 1950) thiab tseem yog siv los ua tus neeg saib xyuas kom tshem tawm cov stains.
Puas TCE txwv hauv Asmeskas?
Thaum Lub Kaum Ob Hlis 2016, siv nws txoj cai raws li Txoj Cai Tswj Kev Tiv Thaiv Kab Mob Tshiab (TSCA), EPA tau thov kom txwv tsis pub siv ntawm trichlorethylene (TCE) hauv aerosol degreasing thiab chaw Kev tu hauv cov chaw tu qhuav, tom qab pom muaj kev pheej hmoo ntau dhau rau cov neeg ua haujlwm, cov neeg siv khoom, thiab cov neeg sawv cev.
TCE puas tseem siv niaj hnub no?
Txawm hais tias qee lub tshuab ziab khaub ncaws siv TCE yav dhau los, feem ntau cov ntxhua khaub ncaws qhuav tam sim no siv tetrachlorethylene (perchloroethylene) lossis 1, 1, 1-trichloroethane. Hauv chaw ua haujlwm, TCE tsis tshua muaj tam sim no yog cov khoom ntshiab.
Dab tsi yog trichlorethylene siv rau feem ntau?
Nws yog siv feem ntau rau ua cov tub yees thiab lwm yam hydrofluorocarbons thiab ua cov kuab tshuaj degreasing rau cov khoom siv hlau. TCE kuj tseem siv tau rau hauv qee cov khoom siv hauv tsev, xws li cov ntaub so huv, cov khoom siv tshuaj aerosol, cov cuab yeej ntxuav, cov xim tshem tawm, cov nplaum nplaum, thiab cov ntaub pua plag thiab cov chaw tshem tawm.
Vim li cas thiaj txwv trichlorethylene?
Fetal toxicity thiab kev txhawj xeeb rau carcinogenic peev xwm ntawm TCE coj mus rau nws tso tseg nyob rau hauv cov teb chaws tsim los ntawm 1980s. Kev siv trichlorethylene hauv cov khoom noj thiab tshuaj lag luam tau uatxwv tsis pub nyob hauv lub ntiaj teb no txij li xyoo 1970s vim kev txhawj xeeb txog nws cov tshuaj lom.
Pom zoo:
Vim li cas thiaj siv cov khoom siv pseudo tseem ceeb?
Pseudocritical txoj cai muab a txhais tau tias txiav txim siab txo cov khoom sib tov kom cov khoom xyaw ntshiab sib xws hauv cov xeev kev sib raug zoo yuav raug siv los kwv yees cov khoom sib xyaw. Pseudo tseem ceeb yog dab tsi? 2.1 Taw qhia.
Puas yog qhov tseem ceeb lossis qhov tseem ceeb?
Emphasise thiab hais txog yog ob qhov kev hloov pauv ntawm cov lus qhia uas txhais tau hais tias qhov tseem ceeb ntawm qee yam. Keeb kwm, hais txog yog tus qauv hauv Askiv Askiv, tab sis niaj hnub no, kev hais qhia ntau dua hauv Askiv thiab Asmeskas Askiv.
Dab tsi yog qhov tseem ceeb thiab vim li cas nws tseem ceeb los txheeb xyuas koj qhov tseem ceeb?
Qhov tseem ceeb yuav coj koj hauv kev txiav txim siab hauv lub neej thiab ua rau koj taug qab. Qhov tseem ceeb tshaj plaws, qhov tseem ceeb tshaj plaws yuav ua rau koj ntseeg siab hais tias "tsis yog." Lawv pab koj txheeb xyuas qhov xav tau tiag tiag hauv koj lub neej, piv rau lwm tus xav tias tseem ceeb.
Puas yog kev siv khoom siv hauv xyoo 1920 yog qhov zoo?
Kev vam meej ntawm xyoo 1920 ua rau cov qauv tshiab ntawm kev noj, lossis kev yuav khoom siv xws li xov tooj cua, tsheb, nqus tsev, khoom zoo nkauj lossis khaub ncaws. Kev nthuav dav ntawm cov credit hauv xyoo 1920 tau tso cai rau kev muag khoom ntawm cov neeg siv khoom ntau dua thiab muab cov tsheb thauj mus los ntawm cov neeg Asmeskas nruab nrab.
Puas yog threonine tseem ceeb lossis tsis tseem ceeb?
Qhov tseem ceeb amino acids tsis tuaj yeem tsim los ntawm lub cev. Yog li ntawd, lawv yuav tsum tau los ntawm cov khoom noj. 9 cov amino acids tseem ceeb yog: histidine, isoleucine, leucine, lysine, methionine, phenylalanine, threonine, tryptophan, thiab valine.
