Xov Xwm - Tus Saib Xyuas Invisible: Cov yeeb nkab xim tiv thaiv lub nroog lifeline li cas

Taw qhia ntawm cov xim tha xim

Hauv cov vaj tse infrastructure thiab kev lag luam ntawm cov zej zog niaj hnub, xa xov mus ua si lub luag haujlwm tseem ceeb. Lawv zoo li kev thauj khoom ntsiag to, twj ywm thauj cov kua, roj av thiab ntau yam tshuaj, kom muaj zog ntawm kev lag luam kev lag luam thiab qhov yooj yim ntawm lub neej txhua hnub. Txawm li cas los xij, qab ntawm kev ua haujlwm ntsiag to ntawm lub raj dej uas ntsiag to, muaj ib tus neeg tsis pom kev "- pipeline pleev xim, uas muab kev tiv thaiv tseem ceeb rau cov raj xa hluav taws xob.

1. Lub ntsiab lus txhais thiab ua haujlwm ntawm cov pipeline xim

Yeeb pleev xim rau, raws li lub npe qhia, yog xim pleev xim tshwj xeeb los siv rau saum npoo ntawm cov kav dej. Nws lub luag haujlwm tseem ceeb mus deb dhau qhov kev kho kom zoo nkauj thiab kev kos npe, tab sis mus tob rau txhua theem ntawm kev tiv thaiv kev ua haujlwm thiab kev ua tau zoo.

(1) corrosion thiab xeb tiv thaiv

Cov kav dej hlau tau txais kev sib xyaw rau corrosion thiab xeb hauv noo, acidic lossis alkaline ib puag ncig. Qhov no yuav tsis tsuas yog luv tawm lub neej ua haujlwm ntawm lub raj dej, tab sis kuj tseem yuav ua rau cov raj xa dej xau, ua rau muaj kuab paug rau ib puag ncig thiab ib puag ncig kev nyab xeeb. Yeeb pleev xim yuav ua tau ib txheej ntawm cov yeeb nkab ntawm cov yeeb nkab kom tiv thaiv noo, oxygen thiab corrosive tshuaj thiab hlau ncaj qha rau kev sib cuag. Ntawm lawv, cov xim tiv thaiv xeb, xws li xim liab, zinc hmoov, thiab tuaj yeem chemicals ntawm cov kab sib txuas, ntxiv txhim kho cov anti-xeb ua hauj lwm. Nyob rau hauv txoj kev no, cov yeeb nkab pleev xim qeeb cov txheej txheem ntawm corrosion thiab xeb ntev tshaj tawm cov kev pabcuam lub neej ntawm cov yeeb nkab, thiab txo tus nqi kho thiab hloov vim cov yeeb nkab puas.

(2) txhim kho huab cua tiv

The pipeline exposed to the outdoors faces the test of various extreme climates, sunlight exposure will cause the coating to age and fade, rain erosion will weaken the adhesion of the coating, and the alternations of cold and heat will cause the pipeline material to expand and Ntsws, yog li cuam tshuam kev ncaj ncees ntawm txheej. Cov yeeb nkab zoo ua yeeb yam muaj huab ua kom zoo heev thiab tuaj yeem tswj tau kev hloov pauv tau ruaj khov hauv kev hloov pauv ntev. Nws cov qauv tshwj xeeb ua rau nws tiv taus ultraviolet hluav taws xob, tiv thaiv txheej laus thiab embrittlement; Nyob rau tib lub sijhawm, cov dej tsis zoo ua kom cov nag tsis nkag mus rau hauv txheej txheej, tsis txhob xeb ntawm cov hlau hauv qab. Nyob rau lub caij ntuj no txias, cov yeeb nkab xim tuaj yeem tiv thaiv cov cawv ntawm qhov kub tsawg, tsis muaj kev tawg thiab tev; Nyob rau lub caij ntuj sov sov, nws tuaj yeem ua tau zoo rwb thaiv tsev, txo qhov nce ntawm qhov kub thiab txias ntawm cov raj xa dej thiab ua kom cov raj xa pa tawm.

(3) Qhia thiab ceeb toom

Nyob rau hauv cov raj hluav taws xob ua kom zoo, cov kav dej rau cov xim sib txawv yuav tsum tau ua kom pom tseeb kom cov xim pom tseeb kom tau txheeb xyuas thiab tswj lawv. Piv txwv, roj pipelines feem ntau yog pleev xim rau cov lus ceeb toom ntawm cov kev phom sij thiab kev siv tshwj xeeb; Cov kav dej roj hluav taws yog pleev xim liab los xyuas kom lawv tuaj yeem tau sai thiab siv thaum muaj xwm txheej ceev. Ib qho ntxiv, cov xim pleev cov yeeb nkab kuj tuaj yeem ntxiv cov cim ceeb toom hauv qhov chaw txaus ntshai, xws li "kev nyab xeeb loj", "tsis txhob kov" thiab lwm yam. Cov paib no tsis tuaj yeem ua rau cov neeg ua haujlwm rau kev nyab xeeb rau cov neeg ua haujlwm tsis muaj xwm txheej ceev, nrawm nrawm, thiab txo cov kev raug xwm ceev.

(4) txhim kho kev ua kom loog

Txawm hais tias kev zoo nkauj tsis yog cov tub ntxhais ua haujlwm ntawm cov xim yeeb, ib qho huv si, xim zoo nkauj, xim zoo nkauj heev tuaj yeem txhim kho cov yeeb nkab tag nrho ntawm cov yeeb nkab system. Hauv cov chaw muaj kev lag luam, qauv txheem thiab unified yeeb cov xim hlau tuaj yeem qhia txog qib kev tswj hwm thiab cov duab ntawm cov lag luam; Hauv cov chaw pej xeem, xws li cov nroog hauv nroog, thaj chaw nyob, thiab lwm yam, xim av xim tuaj yeem txo cov xim hlau thiab ua kom ib puag ncig tshuab ntxhua khaub ncaws thiab ua kom zoo dua. Tsis tas li ntawd, cov tsos zoo tuaj yeem ua kom pej xeem kev ntseeg siab thiab txaus siab nrog cov cuab yeej siv hluav taws xob thiab txhim kho qhov zoo ntawm lub nroog.

2, cov hom thiab cov yam ntxwv ntawm cov raj pleev xim

Muaj ntau cov raj pleev xim rau cov kav dej, txhua tus nrog cov cim tshwj xeeb thiab cov xwm txheej thov kom tau raws li cov kav kev tiv thaiv kev sib txawv thiab cov haujlwm sib txawv.

(1) tiv thaiv xeb xim

Anti-xeb pleev xim yog ib txheej tshwj xeeb siv los tiv thaiv cov xeb hlau, thiab yog ib qho ntawm cov txheej txheem txheej txheem rau kev tiv thaiv kab hluav taws xob. Nws feem ntau muaj tshwj xeeb los tiv thaiv cov xim xeb thiab cov ntxiv, uas tuaj yeem tsim cov hlau, noo noo thiab cov hlau, thiaj li ua kom muaj kev cuam tshuam ntawm xeb.
Anti-xeb pleev xim yog feem ntau muab faib ua ob pawg: oily anti-xeb pleev xim thiab dej-ua los tiv thaiv xeb pleev xim. Roj-based anti-xeb pleev xim nrog cov organic solvent ua rau kev ua kom nrawm dua thiab cov lus qhia txog kev noj qab haus huv, muaj qee qhov kev noj qab haus huv thiab tib neeg kev noj qab haus huv, Yog li kev siv yog raug rau qee yam kev txwv. Hauv kev sib piv, raws li los tiv thaiv xeb pleev xim rau cov dej ua rau kev tiv thaiv ib puag ncig, uas muaj yooj yim hlawv, thiab ua tau raws li cov cai ntawm ib puag ncig niaj puag ncig. Txawm li cas los xij, nws lub sijhawm ziab yog qhov tsis ntev, thiab nws cov tshuaj tiv thaiv xeb yuav tsis zoo dua li cov roj-xeb los tiv thaiv xeb xim hauv qee kis.
Nyob rau hauv cov nqe lus ntawm kev tawm tsam pigments, ib txwm liab txhuas, zinc poov, zinc phosphate thiab li ntawd. Cov xim liab liab los tiv thaiv xeb xim muaj cov txhuas zoo, tab sis vim tias xim liab muaj cov hmoov txhuas muaj cov hmoov txhuas muaj cov hmoov txhuas thiab tib neeg lub cev, nws tau txwv maj mam. Zinc Plant anti-xeb pleev xim siv cov kev tiv thaiv xeb ntawm zinc, uas tuaj yeem muab cov khoom tiv thaiv ntev xeb, tshwj xeeb yog tsim nyog rau kev ua tub rog thiab lwm lub sijhawm muaj xeb. Zinc Phosphate Anti-xeb Posting Paint Paint nrog Hlau Txawv Tiv Thaiv Daim Duab Zoo, uas muaj cov tshuaj tiv thaiv zoo thiab dej tsis kam zoo.

(2) tiv thaiv cov xim corrosion

Anti-corrosion xim yog ib txheej tshwj xeeb tsim los tawm tsam cov tshuaj yaig, thiab ua cov roj av, kev phom sij, dej phwj tuaj thiab lwm yam lag luam. Raws li cov qauv sib txawv, tiv thaiv corrosion corrosion tuaj yeem faib ua cov xim acid-resistant, alkali-paus pleev xim thiab lwm hom.
Acid-resistant xim yog tsuas yog siv los tiv thaiv cov xeb ntawm cov tshuaj acidic, xws li sulfuric acid, hydrochloric acid, hydrochloric acid thiab li ntawd. Cov qauv no feem ntau muaj cov txheej txheem acid-resistant thiab cov fitters tshwj xeeb uas tswj hwm kev ncaj ncees thiab kev ruaj ntseg ntawm cov acidic ib puag ncig. Alkali Resistant pleev xim yog rau cov tshuaj Alkaline, xws li sodium hydroxide, poov tshuaj hydrochod, thiab lwm yam, muaj zoo alkali tsis kam. Cov tshuaj tsuag ntsev pleev xim yog kom tiv taus ntsev txau thiab cov chaw muaj xeb tshwj xeeb, kom tiv thaiv ntsev tso rau hauv ntug dej hiav txwv, los ntawm kev ua kom huv si
Thaum xaiv cov xim tiv thaiv corrosion, nws yog qhov tsim nyog yuav tsum tau nkag siab txog qhov nruab nrab, ua haujlwm kub, siab thiab lwm yam kev thauj mus los ntawm kev thauj khoom. Piv txwv li, hauv cov raj dej pipeline, yog tias kev xa cov tshuaj muaj kuab lom neeg, nws yog ib qho tsim nyog los xaiv cov tshuaj pleev cov tshuaj tua kab thiab xim sib xws raws li qhov tshwj xeeb ntawm cov tshuaj.

(3) Kub tiv taus cov xim

Hauv qee cov ntawv thov tshwj xeeb, xws li cov kav dej tshwj xeeb, kev nqus cov kav dej sov, thiab lwm yam yuav tsum ua haujlwm ntev ntev hauv kev kub ib puag ncig. Cov xim kub tiv thaiv kub yog tsim kom tau raws li qhov kev thov no.
Cov xim kub tiv thaiv kub tuaj yeem tswj hwm qhov ruaj khov ntawm cov txheej txheem hauv qab cov kev mob siab, tsis muaj muag muag, ntws tawm thiab lwm yam tshwm sim. Nws lub ntsiab lus tseem ceeb xws li cov dej kub siab tiv taus cov resin, cov xim kub tiv taus cov xim thiab cov haujlwm ua haujlwm. Silicone Kev Tiv Thaiv Kub Xes Kub yog ib hom kev kub siab ua tau thiab tuaj yeem siv sijhawm ntev ntawm 200 ° Ntau xim ntau dua cov xim dej siab, txog 800 ° C Los yog tseem ntau tshaj 1000 ° C, tab sis nws yooj thiab cov nplaum tsis zoo.
Txhawm rau kom muaj cov nyhuv ntawm cov xim kub siab, nruj nruj ua ntu zus yog qhov yuav tsum tau ua ntej siv cov roj, xeb thiab oxide. Nyob rau tib lub sijhawm, thaum lub sijhawm tsim qauv, kev saib xyuas yuav tsum tau them rau cov txheej txheem tuab thiab kev sib txawv ntawm cov kev tshwm sim ntawm cov hauv zos tuab dhau los lossis yuag dhau.

(4) cov xim insulating

Rau cov raj xa hluav taws xob uas xa cov khoom siv hluav taws xob, xws li cov hlua cable tiv thaiv, thiab lwm yam, rwb thaiv tsev kev ua tau zoo yog qhov tseem ceeb. Cov xim insulating tuaj yeem tsim cov txheej txheem insulating rau saum npoo ntawm raj, tiv thaiv kev nyab xeeb ntawm cov khoom siv hluav taws xob.
Insulating pleev xim feem ntau yog tsim cov khoom hluavtaws, cov kuab tshuaj thiab insulting tsis kam, voltage resistance, voltage resistance, thiab noo noo tsis kam. Cov xim pleev xim rau ib txwm muaj xws li alkyd insulating pleev xim, polyester insulating pleev xim, epoxy insulating pleev xim thiab lwm yam. Thaum xaiv cov xim pleev xim, nws yog qhov tsim nyog kom muaj kev nkag siab ntau yam xws li kev ua haujlwm voltage, siv ib puag ncig ua haujlwm, siv cov kev xav tau ntawm cov raj xa dej.

(5) Kev tiv thaiv ib puag ncig cov xim

Nrog kev txhim kho thoob ntiaj teb rau kev tiv thaiv ib puag ncig, ib puag ncig cov xim pleev xim zoo nkauj tau dhau los ua kev txhim kho ntawm kev ua lag luam. Cov xim pleev xim no txo cov emission ntawm kev sib txuas ntawm cov organic (VOC) hauv kev tsim khoom thiab siv cov tshuaj lom zem, thiab tseem txo cov kev phom sij ntawm huab cua,
Kev tiv thaiv ib puag ncig cov xim feem ntau yog suav nrog cov xim av-ua xim, cov xim zoo xim thiab lwm hom. Waterborne pleev xim siv cov dej kom dej, tsis muaj qhov zoo ntawm kev tiv thaiv ib puag ncig, kev nyab xeeb, tsis muaj nplaim taws thiab li ntawd. Los ntawm nce cov ntsiab lus hauv cov xim, kev siv cov kuab tshuaj yog txo qis, yog li txo lub suab tawm suab. Cov xim pleev xim yog yuav luag cov kuab tshuaj dawb thiab muaj cov khoom siv zoo thiab tshuaj lom neeg, tab sis kev tsim kho cov kev tsim kho siab dua.
Kev tiv thaiv ib puag ncig tsis tsuas yog ua tau zoo rau kev tiv thaiv ib puag ncig, tuaj yeem ua tau kev tiv thaiv kev tiv thaiv ntawm ntau lub raj dej, thiab tau ua rau muaj kev sib raug zoo rau kev txhim kho kom ruaj khov.

3. Xaiv ntawm cov raj xa dej xim pipeline

Xaiv cov xim pleev xim xis yog tus yuam sij los xyuas kom cov nyhuv tiv thaiv thiab kev pabcuam lub neej ntawm cov yeeb nkab. Thaum ua ib qho kev xaiv, ntau tus ntawm cov xwm txheej yuav tsum tau txiav txim siab kom ua tau raws li cov dej num hauv qhov chaw ib puag ncig thiab kev ua haujlwm.

(A) kev siv cov raj xa dej ib puag ncig

Cov pa dej ib puag ncig ntawm cov yeeb nkab yog qhov kev txiav txim siab thawj zaug hauv kev xaiv cov yeeb nkab pleev xim. Cov cheeb tsam sib txawv muaj qhov sib txawv uas yuav tsum muaj rau kev ua tau zoo ntawm cov txheej txheem.
Yog hais tias cov raj xa dej tau nruab rau hauv av noo ib puag ncig, xws li cov kav dej hauv av, thiab lwm yam av noo. Cov xim pleev xim no feem ntau muaj cov dej tsis kam ua tau zoo thiab tshuaj lom neeg tiv thaiv, uas tuaj yeem tiv thaiv cov yaig ntawm dej thiab tshuaj lom nyob hauv av av.
For pipelines exposed to the outdoors, such as overhead heat pipelines, oil pipelines, etc., they need to withstand the test of natural factors such as sun exposure, rain erosion, wind and sand erosion. Yog li, cov yeeb nkab pleev xim nrog huab cua zoo thiab hnav tsis kam yuav tsum tau raug xaiv kom ntseeg tau tias qhov chaw sab nraud sab nraum zoov ntev.
Yog tias cov raj xa dej nyob hauv ib puag ncig kub thiab cua sov cog chav, thiab lwm yam., Tom qab ntawd qhov kev xaiv kub tiv thaiv yog qhov kev xaiv zoo tshaj plaws. Cov xim pleev no tuaj yeem tswj hwm nws lub cev nqaij daim tawv thiab tshuaj lom neeg thaum muaj hluav taws xob kub, kev tiv thaiv kev teeb meem thiab lwm yam teeb meem vim muaj qhov kub.

(B) cov tshuaj nqa los ntawm pipelines

Cov khoom thauj los ntawm cov raj xa dej tseem muaj qhov cuam tshuam tseem ceeb rau kev xaiv cov yeeb nkab pleev xim. Cov tshuaj sib txawv muaj cov tshuaj sib txawv thiab lub cev, uas tuaj yeem ua rau xeb, kev sib cais lossis hnav ntawm cov yeeb nkab txheej.
Yog tias cov raj xa dej thauj cov kua ntshav, xws li cov kua qaub, thiab lwm yam, ces koj yuav tsum xaiv cov yaig ntawm cov tshuaj yaig uas muaj kuab lom. Piv txwv li, cov raj xa dej uas xa cov roj acid
Rau kis tau cov nplaim hluav taws thiab cov roj tawg xws li roj thiab roj av, ntxiv rau kev txiav txim siab los tiv thaiv hluav taws xob zoo li qub los ntawm kev ua kom hluav taws xob lossis tawg cov xwm txheej.
Yog tias nws yog cov khoom noj khoom haus lossis dej haus cov dej pipeline, yuav tsum tau siv cov khoom siv tshuaj tiv thaiv kev noj qab haus huv, tiv thaiv kev noj qab haus huv thiab kev nyab xeeb ntawm cov pej xeem Cov.

(C) kev tsim kho

Cov kev tsim kho cov cai muaj tus cwj pwm ncaj qha rau kev xaiv thiab kev tsim kho cov khoom pleev cov nplooj ntoo. Txoj kev tsim qauv, qhov cua ntawm cov chaw tsim kho, thiab cov kev kho kom zoo yog txhua yam uas yuav tsum tau txiav txim siab.
Cov xim sib txawv nyias yog qhov haum rau cov qauv kev tsim qauv. Piv txwv li, qee cov xim pleev xim yog tsim rau kev txhuam hniav vim tias lawv cov viscosity heev thiab tuaj yeem sib xyaw nrog rau saum npoo ntawm cov leeg ntawm cov txhuam; Lwm cov xim av yog qhov tsim nyog dua rau txau vim tias lawv tau ua ib lub thinner, ntau txheej txheej.
Qhov chaw tsim kho ntawm tus chaw tsim cai yog tseem ceeb heev. Hauv qhov chaw tsis zoo, pleev xim nrog cov khoom siv tsis zoo (VOC) cov ntsiab lus yuav tsum tau raug tsim txom rau kev kho mob ntawm cov neeg ua haujlwm thiab cov pa phem rau ib puag ncig.
Tsis tas li ntawd, cov kev kho mob xav tau ntawm cov yeeb nkab nto yuav tseem cuam tshuam rau kev xaiv cov xim. Yog hais tias lub raj dej ntawm cov raj xa hluav taws xob yog qhov muaj kuab paug xws li roj av, nws yog qhov ua tau zoo nyob rau hauv kev kho mob saum npoo av, lossis txoj kev kho kom zoo dua qub ua ntej kev tsim kho.

(D) nyiaj txiag

Thaum xaiv cov xim yeeb yaj kiab, peev nyiaj kuj yog qhov tseem ceeb uas tsis tuaj yeem tsis quav ntsej. Tus nqi ntawm ntau hom thiab hom yeeb nkab xim txawv txav heev, yog li nws yog ib qho tsim nyog los tsim nyog raws li cov peev txheej uas yuav tsum tau ua raws li kev tiv thaiv kev tiv thaiv.
Feem ntau, kev ua tau zoo yeeb cov xim hlau yog kim, tab sis lawv tuaj yeem muab kev pabcuam ntev dua thiab kev tiv thaiv zoo dua. Yog tias cov peev nyiaj tsawg, koj tuaj yeem xaiv cov khoom siv tau nqi qee yam siv tau, tab sis nco ntsoov tias nws txoj kev ua tau zoo tuaj yeem ua tau raws li qhov kev tiv thaiv kev tiv thaiv kev tiv thaiv kev tiv thaiv yooj yim ntawm cov raj xa dej.
Nyob rau tib lub sijhawm, nws tseem tsim nyog los xav txog kev saib xyuas tus nqi ntawm cov kav hlau pleev xim. Qee cov yeeb nkab zoo cov yeeb nkab zoo, txawm hais tias thawj zaug kev nqis peev yog qhov siab, tej zaum yuav muaj kev lag luam ntev vim lawv cov khoom lag luam zoo thiab tsawg zaus.

4, kev siv thev naus laus zis ntawm cov nplooj ntxaij pleev xim

Kev tsim kho cov thev naus laus zis yog qhov txuas tseem ceeb los xyuas kom cov nyhuv tiv thaiv kab yees. Tsuas yog los ntawm nruj me ntsis tom qab cov txheej txheem tsim qauv txheem tuaj yeem peb ua kom paub tseeb tias qhov ua tau zoo thiab ua tau zoo ntawm txheej sib ntsib cov hom phiaj.

(1) Kev Kho Mob Nto

Kev kho deg yog theem tseem ceeb ntawm cov raj xa dej pleev xim, thiab nws cov khoom zoo cuam tshuam cov nplaum thiab kev tiv thaiv nyhuv ntawm cov txheej txheem.
Ua ntej kev kho deg, qhov saum npoo yuav tsum tau muab ntxuav kom huv kom tshem tawm cov pa phem xws li roj, xeb, xeb, thiab oxide. Rau cov kav dej rusted tiag tiag xeb yog feem ntau nqa tawm los ntawm sandblasting, pickling, sib tsoo thiab lwm txoj kev. Blasting yog ib qho kev tiv thaiv xeb, uas tau tshem tawm cov xeb thiab oxidation txheej los ntawm kev kub ceev, kom cov oliidation txheej los ntawm kev kub siab txog ib qho kev sib tw thiab txhim kho cov nplaum ntawm txheej. Pickling yog siv cov kua qaub kom yaj cov xeb thiab oxide nyob rau ntawm cov raj xa dej los tiv thaiv cov khoom seem ntawm cov raj xa pa rau lub raj xa pa. Sib tsoo yog haum rau cov xeb xeb lossis thaj chaw me me.
Ntxiv rau kev tshem tawm xeb, nws tseem tsim nyog kom tshem tawm cov roj thiab hmoov av ntawm cov raj xa dej. Cov hau kev xws li cov kuab tshuaj ntxuav tu, quaj tu lossis kub siab dej ntws tuaj yeem siv tau. Tom qab txoj kev kho deg ua tiav, nws yuav tsum tau kuaj xyuas nyob rau lub sijhawm kom ntseeg tau tias cov yeeb nkab nto ntsib cov kev nyiam huv thiab kev xav tau.

(2) pre-txheej

Ua ntej-txheej yog cov txheej txheem ntawm pre-txheej txheej ntawm cov raj xa dej uas yog qhov nyuaj pleev xim, xws li weld, lub pob txha sib koom ua ke.
Vim yog cov duab nyuaj, cov ntu no yog cov teeb meem xws li nyias txheej thiab ploj txheej txheej txheem kos duab, yog li lawv yuav tsum tau kho ua ntej. Cov xim siv nyob rau hauv cov txheej txheem ua ntej yuav tsum yog tib yam li cov txheej txheem tseem ceeb, thiab rab phom me me kom ntseeg tau tias cov ntu no tau tiv thaiv kom txaus.

(3) Painting

Painting yog qhov txuas tseem ceeb ntawm cov raj xa dej pleev xim, raws li hom pipeline pleev xim thiab kev tsim kho cov kev tsim kho, xaiv txoj kev pleev xim tsim nyog.
Txhuam txheej yog ib qho kev coj ua ib txwm muaj, haum rau thaj chaw me, cov duab ntawm cov yeeb nkab lossis kho hauv zos. Thaum siv tus txhuam txhuam, ua tib zoo mloog rau lub hardness thiab dav ntawm cov kab txhuam, kom paub meej tias cov txheej thiab tsis muaj zog thiab tsis muaj xau.
Cov txheej txheej rau cov menyuam yog tsim nyog rau thaj chaw loj ntawm cov raj xa dej uas muaj zog, tuaj yeem txhim kho cov kev tsim kho, tab sis cov txheej txheej tuab yog nyias.
Cov txheej txheej rau cov menyuam yog tsim nyog rau thaj chaw loj ntawm cov raj xa dej uas muaj zog, tuaj yeem txhim kho cov kev tsim kho, tab sis cov txheej txheej tuab yog nyias.

Txog Peb

Peb lub tuam txhabyeej ib txwm tau ua adering rau "'science thiab thev naus laus zis, ua tau zoo ntawm LS0900L: .2000 qhov kev pab cuam zoo ntawm LS0900L: .2000 qhov kev lees paub ruaj khov, yeej kev lees paub ntawm cov neeg siv feem ntau Cov.Raws li tus kws tshaj lij thiab muaj zog suav Hoobkas, peb tuaj yeem muab cov qauv rau cov neeg siv khoom uas xav yuav, yog tias koj xav tau xim, thov hu rau peb.