Cov txheej txheem:
Video: Koj npaj PVA li cas?
2024 Tus sau: Stanley Ellington | [email protected]. Kawg hloov kho: 2023-12-16 00:17
Nyhav 40 grams polyvinyl cawv rau hauv 1-Lborosilicate iav beaker. Sau lub beaker rau 1-L cim nrog dej kub; do. Npog nrog microwaveable yas qhwv. Microwaveon siab li 3 feeb; do thiab kub rau ib qho ntxiv 3 feeb.
Ib yam li ntawd, tej zaum koj yuav nug, koj yuav ua li cas yaj PVA?
Yuav ua li cas yaj PVA
- Dej sov. Cov dej sov yuav txo lub sijhawm so.
- Sib tov. Siv nplawm/khiav dej kom txo tau lub sij hawm dissolving.
- Pliers. Koj tuaj yeem ua kom ceev PVA tawg los ntawm kev tso cov ntawv luam tawm hauv dej li ntawm 10 feeb, tom qab ntawd tshem tawm feem ntau ntawm kev txhawb nqa nrog cov pliers.
Ib yam li ntawd, PVA hmoov siv rau dab tsi? Polyvinyl cawv ( PVA , qee zaum hu ua PVOH) yog dej-soluble polymer siv dav inadhesives, xim, sealants, coatings, textiles, plastics, thiab lwm yam. Thepolymer yog ib txwm nkag rau hauv hmoov daim ntawv thiab ntau qib muaj nyob nrog sib txawv viscosity thiab solubility yam ntxwv.
Ua li no, PVA ua li cas?
Hloov chaw, PVA yog ua los ntawm dissolving lwmpolymer, polyvinyl acetate (PVAc), nyob rau hauv ib tug cawv xws li methanoland kho nws nrog ib tug alkaline catalyst xws li sodium hydroxide. Cov tshuaj qauv ntawm lub resulting vinyl cawv repeatingunits yog:.
PVA txheej yog dab tsi?
PVA yog ib qho hluavtaws, tsis muaj ntxhiab thiab tsis muaj xim polymer uas nyiam rau txheej daim ntawv thov. Nws tuaj yeem yaj hauv dej ntawm 80-90 ° C. Yog koj xav tau lub tsho tiv no hydrophilic los yog dej soluble nto, koj siv lub PVA daws ncaj qha.
Pom zoo:
Lub koom haum npaj npaj txhais li cas?
Lub koom haum npaj tau qhia txog kev sib raug zoo ntawm tib neeg, txheej txheem, tshuab thiab kev ntsuas kev ua haujlwm. Nws yuav tsum tau synchronization thiab kev sib koom tes yam tsis muaj qhov kev siv yuav ua tiav
Dab tsi yog kauj ruam thib peb ntawm txoj kev npaj npaj tos?
Qhov thib peb kauj ruam yog Kev Ua Ntej Muag Kev Pom Zoo uas ua kom cov neeg muag khoom siv sijhawm feem ntau
Dab tsi yog kev kwv yees hauv tib neeg kev npaj npaj?
Kev kwv yees ntawm tib neeg (HR) suav nrog kev xav tau kev ua haujlwm thiab cov teebmeem uas lawv yuav muaj rau kev lag luam. Lub tuam tsev HR tau kwv yees ob qho tib si luv luv thiab ntev cov neeg ua haujlwm xav tau raws li kev muag khoom, kev loj hlob hauv chaw ua haujlwm, attrition thiab lwm yam uas cuam tshuam rau lub tuam txhab xav tau kev ua haujlwm
Koj yuav tsum rov ntsuam xyuas koj txoj kev npaj Haccp ntau npaum li cas?
Ntau zaus ntawm Kev Tshawb Fawb lossis Kev Tshawb Fawb. FDA Food Safety Modernization Act (FSMA) Kev Tiv Thaiv Kev Tiv Thaiv rau Tib Neeg Txoj Cai Khoom Noj tau hais tias koj yuav tsum ua qhov kev tshuaj xyuas rov qab ntawm cov phiaj xwm kev nyab xeeb khoom noj tag nrho tsawg kawg ib zaug txhua 3 xyoos
Kev npaj npaj yog dab tsi?
Kev Npaj & Kev Npaj. Lus Txhais: Siv cov txheej txheem tsim nyog, txheej txheem thiab txheej txheem kom ua tau raws li lub hom phiaj. Kev npaj ua tau zoo thiab lub koom haum xav tau kev muaj peev xwm los tsim thiab siv cov txheej txheem tsim nyog, ua kom tiav cov hom phiaj