Cellulose etherinogadzirwa kubva ku cellulose ne etherification reaction neimwe kana akati wandei etherification ejenti uye yakaoma kugaya.Zvinoenderana neakasiyana makemikari zvimiro zveether zvinotsiva, cellulose ethers inogona kupatsanurwa kuita anionic, cationic, uye isiri ionic ethers.Ionic cellulose ethers inonyanya kusanganisira carboxymethyl cellulose ethers (CMC);Non ionic cellulose ethers inonyanya kusanganisira methyl cellulose ether (MC), hydroxypropyl methyl cellulose ether (HPMC), uye hydroxyethyl cellulose ether (HC).Non ionic ethers akapatsanurwazve kuita ether-soluble ethers uye oiri soluble ethers, uye anonyanya kushandiswa muzvigadzirwa zvedhaka.Pamberi pe calcium ions, ionic cellulose ether haina kugadzikana, saka haiwanzo shandiswa mune yakaoma yakasanganiswa dhaka zvigadzirwa uchishandisa simende, hydrated lime, uye zvimwe cementitious zvinhu.Non ionic water-soluble cellulose ethers anoshandiswa zvakanyanya muindasitiri yezvivakwa zvekuvaka nekuda kwekumira kwavo kugadzikana uye kuchengetedza mvura.
1. Chemical properties ye cellulose ether
Imwe neimwe cellulose etherine chimiro chekutanga che cellulose - iyo yakasvibiswa glucose chimiro.Mukugadzira cellulose ether, iyo cellulose fibers inotanga kupiswa muine alkaline solution, yozobatwa ne etherification agents.Zvigadzirwa zvefibrous reaction zvinocheneswa uye zvinogayiwa kuita hupfu hwakafanana nehumwe hunyoro.
Munguva yekugadzirwa kweMC, methane chloride chete ndiyo inoshandiswa se etherifying agent;Pamusoro pekushandisa methane chloride mukugadzirwa kweHPMC, epoxy propylene inoshandiswawo kuwana hydroxypropyl substituents.Akasiyana-siyana cellulose ethers ane akasiyana methyl uye hydroxypropyl substitution rates, ayo anokanganisa kunyungudika kwe organic kwe cellulose ether mhinduro uye tembiricha yegel yemafuta nezvimwe zvinhu.
2. Mamiriro ekushandiswa kwe cellulose ether
Cellulose etheris a non ionic semi synthetic polymer ine mvura-soluble uye solvent-based properties, uye maitiro ayo anosiyana mumaindasitiri akasiyana.Semuyenzaniso, mune makemikari ekuvaka zvinhu, ine zvinotevera composite mhedzisiro:
① Mushandi wekuchengetedza mvura ② Thickener ③ Kuenzana chivakwa ④ Firimu kugadzira chivakwa ⑤ Adhesive
MuPVCindasitiri, iri emulsifier uye inoparadzira;Muindasitiri yemishonga, cellulose imhando yebinder uye inononoka-kuburitsa furemu zvinhu, uye chaizvo nekuti ine akawanda anoumbwa mhedzisiro, ayo mashandisirwo minda ndiwo zvakare akawandisa.Pazasi, isu tichatarisa nzira dzekushandisa uye basa re cellulose ether mune zvakasiyana siyana zvekuvaka.
(1) Mune latex pendi:
Mune latex pendi indasitiri, zvinodikanwa kusarudzahydroxyethyl cellulose.Iyo yakajairika yekumisikidzwa kweakaenzana viscosity ndeye RT30000-5000cps, inoenderana neiyo HBR250 yakatarwa.Iyo referensi dosage inowanzotenderedza 1.5 ‰ -2 ‰.Basa guru re hydroxyethyl mu latex pendi kukora, kudzivirira pigment gel, inobatsira mukupararira kwe pigment, latex kugadzikana, kuvandudza viscosity yezvikamu, uye kubatsira mukuita kwekuita kwekuvaka: hydroxyethyl cellulose iri nyore kushandisa, inogona kunyungudika mukati. mvura inotonhora nemvura inopisa, uye haina kukanganiswa neiyo PH kukosha.Inogona kushandiswa zvakachengeteka pakati pePI kukosha 2-12.Nzira nhatu dzinotevera dzinoshandiswa: I Kuwedzera kuwedzera mukugadzirwa: Iyi nzira inofanira kusarudza hydroxyethyl cellulose inononoka mhando, ine nguva yekuparara inopfuura maminitsi makumi matatu.Matanho ekushandisa ndeaya anotevera: ① Isa huwandu hwehuwandu hwemvura yakachena mumudziyo une chidhinha chepamusoro;② Tanga kubvongodza nekumhanya kwakaderera pasina kumira, Panguva imwecheteyo, zvishoma nezvishoma uye zvakaenzana wedzera hydroxyethyl kune mhinduro.③ Ramba uchimutsa kusvika zvinhu zvese zvatota.④ Wedzera zvimwe zvinowedzera uye alkaline additives.⑤ Shingairira kusvikira yose hydroxyethyl yanyungudutswa zvachose.Zvadaro wobva wawedzera zvimwe zvikamu mufomu uye kugaya kusvikira chigadzirwa chapera.II.Gadziriro yedoro raamai rekushandisa: Iyi nzira inogona kusarudza pakarepo mhando uye ine anti mold effect pa cellulose.Kubatsira kweiyi nzira ndeyokuti ine kushanduka kukuru uye inogona kuwedzerwa zvakananga kune latex pendi.Nzira yekugadzirira yakafanana nematanho ① kusvika ④.III.Kugadzirira kweConge sezvinhu zvekushandisa mune ramangwana: Sezvo organic zvinonyungudutsa zvakashata zvinonyungudutsa (zvisinganyunguriki) zvehydroxyethyl, zvinonyungudutsa izvi zvinogona kushandiswa kugadzira Congee senge zvinhu.Inonyanya kushandiswa organic solvent ndiyo organic liquid mu emulsion paint formula, yakadai se ethylene glycol, propylene glycol uye film forming agent (yakadai se diethylene glycol butyl acetate).Iyo Congee senge hydroxyethyl cellulose inogona kuwedzerwa zvakananga kupende, uyezve ramba uchimutsa kusvika yanyungudika zvachose.
(2) Mukukwesha madziro putty:
Parizvino, putty ine hushamwari kwezvakatipoteredza iyo isingaende kumvura uye kukwesha yakave yakakosha mumaguta mazhinji eChina.Mumakore mashoma apfuura, nekuda kwekubuda kwe formaldehyde gasi kubva ku putty yakagadzirwa neadhesive yekuvaka, iyo inokuvadza hutano hwevanhu, chivakwa chekunamatira chakagadzirwa neacetal reaction ye polyvinyl doro uye formaldehyde.Saka chinhu ichi chiri kubviswa zvishoma nezvishoma nevanhu, uye chinotsiva chinyorwa ichi ndeye cellulose ether series zvigadzirwa, zvinoreva kugadzira zvinhu zvekuvaka zvine hushamwari.Cellulose parizvino ndiyo chete zvinhu zviripo.Mumvura inodzivirira putty, inogona kukamurwa kuita mhando mbiri: yakaoma poda putty uye putty paste.Kazhinji, yakagadziridzwa methyl cellulose uye hydroxypropyl methyl inosarudzwa semhando mbiri dzeputty, uye iyo viscosity yakatarwa kazhinji iri pakati pe30000-60000 cps.Basa guru re cellulose mu putty kuchengetedza mvura, bond, uye lubricate.Nekuda kweakasiyana mafomati evagadziri akasiyana, mamwe ari grey calcium, light calcium, chena simende, zvichingodaro, nepo mamwe ari gypsum powder, grey calcium, light calcium, etc. iwo mafomula maviri akasiyana zvakare, ane huwandu hwekuwedzera huwandu hunosvika 2 ‰ -3 ‰.Mukuvaka kwekupura madziro putty, nekuda kwekumwe kunyura kwemvura kwechigadziko chemadziro (chiyero chekunyudza kwemvura yemadziro ezvidhinha i13%, uye kunyudzwa kwemvura kwekongiri ndeye 3-5%), pamwe nekunze. evaporation, kana iyo putty ikarasikirwa nemvura nekukurumidza, inokonzera kuputika kana kuputika kwehupfu, uye nokudaro kuderedza simba reputty.Naizvozvo, kuwedzera cellulose ether kuchagadzirisa dambudziko iri.Nekudaro, iyo mhando yekuzadza zvinhu, kunyanya mhando yegrey calcium, yakakoshawo zvakanyanya.Nekuda kweiyo yakakwira viscosity ye cellulose, zvakare inokwidziridza buoyancy ye putty, inodzivirira kudonha panguva yekuvaka, uye yakanyanya kugadzikana uye kuponesa basa kukwenya.Iyo cellulose ether mu powder putty inoda kuwedzerwa kufekitari zvakakodzera.Kugadzirwa kwayo uye kushandiswa kuri nyore, uye zvinhu zvekuzadza uye zvinowedzera zvinogona kusanganiswa zvakaenzana nehupfu hwakaoma.Kuvakwa kwacho kuri nyore, uye kugovera mvura panzvimbo yacho kunoenderana nekuti yakawanda sei inoshandiswa.
(3) Dongo rekongiri:
Mune dhaka rekrete, kuti uwane zvechokwadi simba rekupedzisira, zvakakosha kuti unyatso hydrate simenti.Kunyanya mukuvaka kwezhizha, apo kurasikirwa kwemvura kwekrete kwekongiri kwakakurumidza, zviyero zvakakwana zve hydration zvinotorwa kuchengetedza uye kusasa mvura.Iyi nzira inokonzera tsvina yemvura uye kusagadzikana mukushanda, uye kiyi ndeyokuti mvura iri pamusoro chete, asi iyo yemukati hydration ichiri isina kukwana.Naizvozvo, mhinduro kudambudziko iri ndeiyi:, Kuwedzera masere ekuchengetedza mvura cellulose kune dhaka kongiri kazhinji anosarudza hydroxypropyl methyl kana methyl cellulose, ine viscosity yakatarwa kubva pa20000 kusvika 60000 cps uye kuwedzera kwe2% kusvika 3%.Kutenderedza, mwero wekuchengetedza mvura unogona kuwedzera kusvika pamusoro pe85%.Nzira yekushandisa mudhaka kongiri ndeyekusanganisa hupfu hwakaoma zvakaenzana uye wozodira mvura mumuromo.
(4) Mukupura gypsum, kubatanidza gypsum, uye caulking gypsum:
Nekukurumidza kukura kweindasitiri yekuvaka, kudiwa kwezvinhu zvitsva zvekuvaka kuri kuwedzerawo zuva nezuva.Nekuda kwekuwedzera kuziva kwekuchengetedzwa kwezvakatipoteredza uye nekuenderera mberi kwekuvandudzwa kwekuvaka, zvigadzirwa zve cementitious gypsum zvakakura nekukurumidza.Parizvino, zvigadzirwa zvegypsum zvakajairika zvinosanganisira plastering gypsum, bonding gypsum, embedded gypsum, tile binder, etc. Gypsum plastering imhando yepamusoro yekupura madziro emukati uye denga slabs.Madziro ayo anoshandiswa kupurasita akapfava uye anotsvedzerera, asina kusvuura hupfu uye kunamatira zvakasimba kunheyo, pasina kuputika kana kusvuura, uye nebasa rekudzivirira moto;Bonded gypsum imhando nyowani yekuvaka light board binder, iyo inogadzirwa kubva gypsum seyakadzika zvinhu uye inowedzerwa neakasiyana ekuwedzera simba.Yakakodzera kusungirirana pakati peakasiyana inorganic ekuvaka madziro emidziyo uye ine hunhu hwekusina-chepfu, husina hwema, simba rekutanga, kukurumidza kugadzika, uye kusimba kwakasimba.Icho chinhu chinotsigira chekuvaka bhodhi uye kuvaka block;Gypsum joint filler chinhu chinozadza mapundu pakati pemabhodhi egypsum, pamwe nekugadzirisa kuzadza kwemadziro uye kuputika.Izvi zvigadzirwa zvegypsum zvine mutsara wemabasa akasiyana.Mukuwedzera kune gypsum nemamwe mafirita ane hukama, nyaya yakakosha ndeyekuti iyo yakawedzera cellulose ether additives inoita basa guru.Nekuda kwekuti gypsum yakakamurwa kuita anhydrous gypsum uye hemihydrate gypsum, mhando dzakasiyana dzegypsum dzine mhedzisiro dzakasiyana pakuita kwechigadzirwa.Naizvozvo, kukora, kuchengetwa kwemvura, uye kudzoreredza kunotarisisa kunaka kwezvinhu zvekuvaka gypsum.Dambudziko rinowanzoitika nemidziyo iyi igomba uye kuputika, uye simba rekutanga harigone kusvika.Kuti ugadzirise dambudziko iri, zvinodikanwa kusarudza muenzaniso we cellulose uye iyo composite yekushandisa nzira yevanodzosera.Panyaya iyi, methyl kana hydroxypropyl methyl inowanzosarudzwa se30000 kusvika 60000 cps, pamwe nehuwandu hwe1.5% -2%.Pakati pavo, cellulose inotarisa pakuchengetedza kwayo mvura, kudzoreredza, uye nekuzora zvinhu.Zvisinei, hazvibviri kushandisa cellulose ether seretarder mumutambo uyu, uye zvakakosha kuwedzera citric acid retarder kusanganisa uye kuishandisa pasina kukanganisa simba rekutanga.Mwero wekuchengetedza mvura kazhinji unoreva huwandu hwekurasika kwemvura chaiyo pasina kutorwa kwemvura kunze.Kana rusvingo rwakaoma, kunyura kwemvura uye kubuda kwechisikigo kwepasi pevhu kunoita kuti zvinhu zvirasikirwe nemvura nekukurumidza, izvo zvinozoita kuti pave negomba uye kuputika.Iyi nzira yekushandisa ndeyekusanganisa hupfu hwakaoma.Kana uchigadzirira mhinduro, tapota tarisa kune nzira yekugadzirira mhinduro.
(5) Insulation mortar
Insulation dhaka imhando nyowani yemukati madziro ekudzivirira zvinhu mudunhu rekuchamhembe, inova madziro emadziro anoumbwa nezvinhu zvekudzivirira, dhaka, uye zvinonamira.Cellulose inoita basa rakakosha mukubatanidza uye kuwedzera simba mune ino chinyorwa.Kazhinji, methyl cellulose ine yakakwira viscosity (yakatenderedza 10000eps) inosarudzwa, uye iyo dosage inowanzo pakati pe2 ‰ -3 ‰.Nzira yekushandisa ndiyo yakaoma poda kusanganisa.
(6) Interface agent
Iyo interface mumiririri inofanira kunge iriHPMC20000 cps, uye inonamira yematiles inofanira kunge iri pamusoro pe60000 cps.Mune iyo interface mumiriri, tarisiro inofanirwa kunge iri pane thickening agent, iyo inogona kuvandudza simba rekusimba uye kuramba museve.Isa mushonga wekuchengetedza mvura mukubatanidza matiles kuti asadonha nekukurumidza nekuda kwekurasikirwa nemvura.
3. Indasitiri cheni mamiriro
(1) Indasitiri yepamusoro
Iyo huru mbishi zvinhu zvinodiwa pakugadziracellulose etherzvinosanganisira donje rakanatswa (kana pulp yehuni) uye mamwe anowanzo shandiswa makemikari zvinonyungudutsa, senge epoxy propane, chloromethane, liquid alkali, flake alkali, ethylene oxide, toluene, uye zvimwe zvekubatsira.Iwo mabhizinesi ekumusoro muindastiri iyi anosanganisira akacheneswa donje uye huni pulp kugadzira mabhizinesi, pamwe nemamwe mabhizinesi emakemikari.Kuchinja-chinja kwemitengo yezvinhu zvikuru mbishi yataurwa pamusoro ichange iine madhigirii akasiyana-siyana pamutengo wekugadzira uye mutengo wekutengesa we cellulose ether.
Mutengo wekotoni yakanatswa yakanyanya.Kutora zvinhu zvekuvaka giredhi cellulose ether semuenzaniso, panguva yekubika, chikamu cheyakanatswa donje mutengo wekutengesa mutengo wekuvaka giredhi cellulose ether yaive 31.74%, 28.50%, 26.59%, uye 26.90%, zvichiteerana.Kuchinja-chinja kwemitengo yedonje yakanatswa kuchakanganisa mutengo wekugadzira cellulose ether.Chinhu chikuru chekugadzira donje rakanatswa icotton linter.Cotton linter ndeimwe yezvigadzirwa mukugadzira donje, inonyanya kushandiswa kugadzira zvigadzirwa zvakaita sedonje pulp, donje rakanatswa, uye nitrocellulose.Pane mutsauko wakakura mukukosha kwekushandisa uye kushandiswa kwekotoni linter nekotoni, uye mitengo yavo yakadzikira zvakanyanya pane iyo yekotoni, asi pane kumwe kuwirirana nekushanduka kwemitengo yekotoni.Kuchinja kwemutengo wekotoni linter kuchakanganisa mutengo wedonje rakanatswa.
Kuchinja kwakanyanya mumitengo yedonje yakanatswa kuchave neakasiyana madhigirii ekukanganisa pakutonga kwemitengo yekugadzira, mitengo yechigadzirwa, uye pundutso yemabhizinesi muindasitiri ino.Muchirevo chemitengo yakakwira yedonje rakanatswa uye nemitengo yakachipa yehuni pulp, kuitira kuderedza mutengo, matanda ehuni anogona kushandiswa sechinotsiva uye anowedzera padonje rakanatswa, kunyanya kugadzira cellulose ethers ine yakaderera viscosity senge mishonga uye chikafu. giredhi cellulose ethers.Zvinoenderana nedandemutande rewebhusaiti reNational Bureau of Statistics, muna 2013, nzvimbo yekuChina yekudyara donje yaive mahekita 4.35 miriyoni, uye donje renyika rairimwa matani 6.31 miriyoni.Zvinoenderana nehuwandu hwehuwandu hweChina Cellulose Indasitiri Association, muna 2014, iyo yakazara kubuda kwedonje rakanatswa nemabhizimusi makuru ekugadzira donje akacheneswa aive matani 332000, aine huwandu hwemidziyo.
Iyo mikuru yezvigadzirwa zvekugadzira graphite yakavakirwa makemikari michina isimbi uye graphite kabhoni.Mutengo wesimbi uye graphite kabhoni inoverengera chikamu chepamusoro chemutengo wekugadzira wezvigadzirwa zvemakemikari emagraphite.Kuchinja kwemitengo yezvinhu izvi mbishi kuchave nekukanganisa pamutengo wekugadzira uye mutengo wekutengesa wezvigadzirwa zvemakemikari emagraphite.
(2) Mamiriro ekudzika kwerukova cellulose ether industry
Cellulose ether, se "industrial monosodium glutamate", ine chikamu chakaderera chezvinowedzera uye zvakasiyana-siyana zvekushandiswa, nemaindasitiri ezasi akapararira mune zvakasiyana-siyana zvehupfumi hwenyika.
Kazhinji, kuvaka kwakadzika uye maindasitiri ezvivakwa anozove nekukanganisa kwekukura kwekudiwa kwezvinhu zvekuvaka giredhi cellulose ether.Kana kukura kwemaindasitiri ekuvaka edzimba uye zvivakwa kuri kukurumidza, kudiwa kwekuvaka giredhi cellulose ether mumusika wepamba kuri kukura nekukurumidza.Kana kukura kwezvivakwa zvekuvaka uye maindasitiri ezvivakwa kukadzikira, kudiwa kwekuvaka giredhi cellulose ether mumusika wepamba kunodzikira, zvichiita kuti makwikwi muindasitiri iyi awedzere uye nekumhanyisa maitiro ekurarama kwemabhizinesi muindastiri iyi. .
Kubva 2012, mumamiriro ekudzikira kwekuvaka kwedzimba uye maindasitiri ezvivakwa, hapasati paine shanduko yakakosha mukudiwa kwekuvaka giredhi cellulose ether mumusika wepamba.Zvikonzero zvikuru ndezvi: chekutanga, chiyero chese chekuvaka kwedzimba uye maindasitiri edzimba yakakura, uye huwandu hwemusika hunodiwa hwakakura;Musika mukuru wevatengi wekuvaka giredhi cellulose ether wakawedzera zvishoma nezvishoma kubva kumatunhu akasimukira hupfumi uye yekutanga neyechipiri tier maguta kuenda kumatunhu epakati nekumadokero uye yechitatu tier maguta, kuwedzera mukana uye nzvimbo yekukura kwekuda kwemba;2, Kuwedzerwa kwehuwandu hwe cellulose ether inotora chikamu chakaderera chemutengo wezvigadzirwa zvekuvaka, uye mari inoshandiswa nemutengi mumwechete idiki.Vatengi vakaparadzirwa, izvo zvinogona nyore kuburitsa kuomarara kudiwa.Zvose zvinodiwa mumusika wepasi zvakagadzikana;3, Shanduko yemutengo wemusika chinhu chakakosha chinokanganisa kudiwa kwechimiro chekuvaka giredhi cellulose ether.Kubva 2012, mutengo wezvinhu zvekuvaka giredhi cellulose ether wakadzikira zvakanyanya, zvichikonzera kuderera kukuru kwemitengo yepakati kusvika kune yepamusoro-yekupedzisira zvigadzirwa, kukwezva vatengi vakawanda kutenga uye kusarudza, kuwedzera kudiwa kwepakati kusvika kune yakakwirira-kuguma zvigadzirwa, uye. kudzvanya kudiwa kwemusika uye nzvimbo yemitengo yezvakajairwa modhi zvigadzirwa.
Chiyero chekusimudzira uye kukura kweindasitiri yemishonga kuchakanganisa kudiwa kwemishonga giredhi cellulose ether.Kuvandudzwa kwemararamiro evanhu uye kusimudzira indasitiri yechikafu kunobatsira kufambisa kudiwa kwemusika kwechikafu giredhi cellulose ether.
6. Kuvandudza maitiro e cellulose ether
Nekuda kwekusiyana kwemaitiro mukudiwa kwemusika kweselulosi ether, mamiriro ezvinhu akabuda apo mabhizinesi ane masimba akasiyana anogona kugarisana.Mukupindura kusiyanisa kuri pachena kwekuda kwemusika, vagadziri vedzimba cellulose ether vakatora akapatsanurwa nzira dzemakwikwi zvichienderana nesimba ravo, uku vachinyatso kubata maitiro ekusimudzira uye gwara remusika.
(1) Kuve nechokwadi chekugadzikana kwemhando yechigadzirwa chinoramba chiri musimboti wekukwikwidza we cellulose ether mabhizinesi.
Cellulose etherinoverengera chikamu chidiki chemitengo yekugadzira mumabhizinesi mazhinji ari pasi peindastiri iyi, asi ine simba rakakura pamhando yechigadzirwa.Boka revatengi vepamusoro-soro rinofanirwa kuita zviyedzo zveformula risati rashandisa imwe mhando uye modhi ye cellulose ether.Mushure mekugadzira chimiro chakagadzikana, kazhinji hazvisi nyore kutsiva zvigadzirwa kubva kune mamwe mabhureki, uye zvinodiwa zvepamusoro zvinoiswawo pakugadzikana kwemhando ye cellulose ether.Chiitiko ichi chakanyanya kutariswa muminda yepamusoro-soro senge makambani epamba uye ekunze makuru ekugadzira zvinhu zvekuvakisa, zvigadzirwa zvemishonga, zvekuwedzera zvekudya, PVC, etc. Kuvandudza kukwikwidza kwezvigadzirwa, mabhizinesi ekugadzira anofanirwa kuve nechokwadi chekuti kugadzikana kwemhando dzakasiyana siyana. mabheti e-cellulose ether anopihwa anogona kuchengetedzwa kwenguva yakareba, kuitira kuumba mukurumbira wakanaka wemusika.
(2) Kuvandudza huwandu hwechigadzirwa chekushandisa tekinoroji ndiyo nzira yekusimudzira yemabhizinesi emumba cellulose ether
Nekuwedzera kuri kuita tekinoroji yekugadzira cellulose ether, mwero wepamusoro wetekinoroji yekushandisa inobatsira kumabhizinesi kuti vawedzere kukwikwidza kwavo uye kugadzira hukama hwevatengi hwakagadzikana.Mabhizinesi ane mukurumbira cellulose ether munyika dzakabudirira anonyanya kutora nzira yemakwikwi e "kunangisa vatengi vepamusoro-soro uye kugadzira maapplication uye mashandisiro epasi", kusimudzira.cellulose ethermashandisirwo uye mafomula ekushandisa, uye kumisikidza yakatevedzana yezvigadzirwa zvinoenderana neakasiyana akakamurwa mashandisirwo minda kufambisa kushandiswa kwevatengi, uye kurima pasi pemusika kudiwa kuburikidza neizvi.Makwikwi pakati pemabhizinesi e-cellulose ether munyika dzakabudirira achinja kubva pachigadzirwa kuenda kuhunyanzvi hwekushandisa.
Nguva yekutumira: Aug-31-2023