Kev hloov pauv ntawm cov khoom sib txuas pom hauv cov tsiaj qus, nrog rau tshwm sim los ntawm tib neeg kev ua haujlwm, tuaj yeem suav tias yog cov txheej txheem tshuaj. Reagents nyob rau hauv lawv tuaj yeem yog ob lossis ntau yam khoom uas nyob hauv tib lossis hauv ntau lub xeev ntawm kev sib sau. Nyob ntawm qhov no, homogeneous lossis heterogeneous systems tau txawv. Cov xwm txheej rau kev coj ua, cov yam ntxwv ntawm chav kawm thiab lub luag haujlwm ntawm cov txheej txheem tshuaj lom neeg hauv cov xwm txheej yuav raug txiav txim siab hauv daim ntawv no.
txhais li cas los ntawm tshuaj tiv thaiv
Yog tias, raws li kev sib cuam tshuam ntawm cov tshuaj thawj zaug, cov khoom siv ntawm lawv cov molecules hloov pauv, thiab cov nqi ntawm cov nuclei ntawm cov atoms tseem zoo ib yam, lawv hais txog cov tshuaj tiv thaiv lossis cov txheej txheem. Cov khoom tsim los ntawm lawv cov dej ntws yog siv los ntawm cov txiv neej hauv kev lag luam, kev ua liaj ua teb thiab lub neej txhua hnub. Cov kev sib tshuam loj heevnruab nrab ntawm cov khoom tshwm sim, ob qho tib si nyob rau hauv thiab inanimate xwm. Cov txheej txheem tshuaj muaj qhov sib txawv ntawm lub cev tshwm sim thiab cov khoom ntawm cov xov tooj cua. Cov molecules ntawm cov tshuaj tshiab yog tsim nyob rau hauv lawv, thaum lub cev cov txheej txheem tsis hloov cov muaj pes tsawg leeg ntawm cov tebchaw, thiab atoms ntawm cov tshuaj tshiab tshwm sim nyob rau hauv nuclear tshuaj.
Txoj Cai rau kev siv cov txheej txheem hauv chemistry
Lawv tuaj yeem sib txawv thiab nyob ntawm qhov feem ntau ntawm cov reagents, qhov xav tau ntawm lub zog ntawm sab nraud, nrog rau lub xeev ntawm kev sib sau ua ke (khoom, tov, gases) uas cov txheej txheem tshwm sim. Cov txheej txheem tshuaj lom neeg ntawm kev sib cuam tshuam ntawm ob lossis ntau lub tebchaw tuaj yeem ua tiav raws li kev ua haujlwm ntawm catalysts (piv txwv li, kev tsim cov nitric acid), kub (tau txais ammonia), lub teeb lub zog (photosynthesis). Nrog rau kev koom tes ntawm enzymes nyob rau hauv cov xwm, cov txheej txheem ntawm cov tshuaj tiv thaiv ntawm fermentation (cawv, lactic acid, butyric), siv nyob rau hauv cov zaub mov thiab microbiological industries, yog dav. Txhawm rau kom tau txais cov khoom lag luam hauv kev lag luam organic synthesis, ib qho ntawm cov xwm txheej tseem ceeb yog qhov muaj cov dawb radical mechanism ntawm cov txheej txheem tshuaj. Ib qho piv txwv yuav yog kev tsim cov tshuaj chlorine derivatives ntawm methane (dichloromethane, trichloromethane, carbon tetrachloride, uas tshwm sim los ntawm cov tshuaj tiv thaiv kab mob.
homogeneous catalysis
Lawv yog hom tshwj xeeb ntawm kev sib cuag ntawm ob lossis ntau yam khoom. Lub ntsiab ntawm cov txheej txheem tshuaj tshwm sim nyob rau hauv ib theem homogeneous (piv txwv li, roj - roj) nrog kev koom tes ntawm acceleratorscov tshuaj tiv thaiv, muaj nyob rau hauv nqa tawm cov tshuaj tiv thaiv nyob rau hauv tag nrho cov ntim ntawm mix. Yog hais tias tus catalyst nyob rau hauv tib lub xeev ntawm aggregation li cov reactants, nws tsim mobile intermediate complexes nrog cov pib compounds.
Homogeneous catalysis yog txheej txheem tshuaj lom neeg siv hauv, piv txwv li, roj refining, roj av, naphtha, roj roj, thiab lwm yam roj. Nws siv thev naus laus zis xws li hloov kho, isomerization, catalytic cracking.
YHeterogeneous catalysis
Nyob rau hauv rooj plaub ntawm heterogeneous catalysis, kev sib cuag ntawm cov reactants tshwm sim, feem ntau, ntawm cov khoom nto ntawm lub catalyst nws tus kheej. Yog li-hu ua active chaw yog tsim rau nws. Cov no yog cov cheeb tsam uas qhov kev sib cuam tshuam ntawm cov tshuaj reacting ua tau sai heev, uas yog, cov tshuaj tiv thaiv tus nqi siab. Lawv yog hom tshwj xeeb thiab ua lub luag haujlwm tseem ceeb yog tias cov txheej txheem tshuaj tshwm sim hauv cov hlwb. Tom qab ntawd lawv tham txog cov metabolism - cov tshuaj tiv thaiv metabolic. Ib qho piv txwv ntawm heterogeneous catalysis yog kev lag luam ntawm sulfate acid. Hauv cov cuab yeej sib cuag, cov khoom sib txuas ntawm cov sulfur dioxide thiab oxygen yog rhuab thiab dhau los ntawm cov txee dai khaub ncaws uas muaj cov hmoov tawg ntawm vanadium oxide los yog vanadyl sulfate VOSO 4. Cov khoom uas tshwm sim, sulfur trioxide, ces absorbed los ntawm concentrated sulfuric acid. Cov kua hu ua oleum yog tsim. Nws tuaj yeem diluted nrog dej kom tau txais qhov xav tau ntawm sulfate acid.
Txhim kho cov tshuaj tiv thaiv thermochemical
Kev tso tawm lossis nqus lub zog hauv daim ntawv ntawm tshav kub yog qhov tseem ceeb tshaj plaws. Nws txaus kom nco qab cov kev sib txuas ntawm cov roj: cov pa roj, thee, peat. Lawv yog cov txheej txheem ntawm lub cev thiab tshuaj lom neeg, ib qho tseem ceeb ntawm cov txheej txheem uas yog qhov kub ntawm combustion. Cov tshuaj tiv thaiv cua sov yog dav nyob rau hauv lub ntiaj teb organic thiab nyob rau hauv inanimate xwm. Piv txwv li, nyob rau hauv cov txheej txheem ntawm kev zom, cov protein, lipids thiab carbohydrates tau tawg nyob rau hauv qhov kev txiav txim ntawm biologically active tshuaj - enzymes.
Lub zog tso tawm yog khaws cia hauv daim ntawv ntawm macroergic bonds ntawm ATP molecules. Dissimilation cov tshuaj tiv thaiv yog nrog los ntawm kev tso tawm ntawm lub zog, ib feem ntawm uas yog dissipated nyob rau hauv daim ntawv ntawm tshav kub. Raws li kev zom zaub mov, txhua gram ntawm cov protein muab 17.2 kJ ntawm lub zog, hmoov txhuv nplej siab - 17.2 kJ, rog - 38.9 kJ. Cov txheej txheem tshuaj uas tso tawm lub zog hu ua exothermic, thiab cov uas nqus tau nws hu ua endothermic. Hauv kev lag luam organic synthesis thiab lwm yam thev naus laus zis, cov txiaj ntsig thermal ntawm cov tshuaj tiv thaiv thermochemical suav nrog. Nws yog ib qho tseem ceeb kom paub qhov no, piv txwv li, rau kev xam kom raug ntawm cov nqi ntawm lub zog siv los ua kom sov lub reactors thiab synthesis kem nyob rau hauv uas cov kev tshwm sim tshwm sim, nrog rau kev nqus ntawm tshav kub.
Kinetics thiab nws lub luag haujlwm hauv txoj kev xav ntawm cov txheej txheem tshuaj
Xaiv qhov ceev ntawm cov khoom ua haujlwm (molecules, ions) yog txoj haujlwm tseem ceeb tshaj plaws rau kev lag luam. Nws cov kev daws teeb meem ua kom muaj txiaj ntsig ntawm kev lag luam thiab cov txiaj ntsig ntawm kev siv thev naus laus zis hauv kev tsim tshuaj lom neeg. Rau kev nce ntxivQhov ceev ntawm xws li cov tshuaj tiv thaiv, xws li cov synthesis ntawm ammonia, qhov kev txiav txim siab yuav yog ib qho kev hloov nyob rau hauv siab nyob rau hauv ib tug roj sib tov ntawm nitrogen thiab hydrogen mus txog 30 MPa, raws li zoo raws li kev tiv thaiv ntawm ib tug ntse nce nyob rau hauv kub (qhov kub thiab txias. yog 450-550 ° C yog qhov zoo).
Cov txheej txheem tshuaj siv hauv kev tsim cov sulfate acid, uas yog: pyrites burning, sulfur dioxide oxidation, nqus sulfur trioxide los ntawm oleum, yog nqa tawm nyob rau hauv ntau yam mob. Rau qhov no, siv lub tshuab hluav taws xob pyrite thiab cov cuab yeej tiv tauj. Lawv coj mus rau hauv tus account lub concentration ntawm reactants, kub thiab siab. Tag nrho cov xwm txheej no cuam tshuam los ua cov tshuaj tiv thaiv ntawm tus nqi siab tshaj plaws, uas ua rau nce cov txiaj ntsig ntawm sulfate acid rau 96-98%.
Lub voj voog ntawm cov tshuaj raws li lub cev thiab cov txheej txheem tshuaj nyob rau hauv xwm
Qhov kev paub zoo hais tias "Kev txav mus los yog lub neej" tuaj yeem siv rau cov khoom siv tshuaj lom neeg uas nkag mus rau hauv ntau hom kev sib cuam tshuam (kev cuam tshuam ntawm kev sib xyaw ua ke, hloov pauv, decomposition, pauv). Molecules thiab atoms ntawm cov tshuaj lom neeg muaj nyob rau hauv qhov kev txav mus tas li. Raws li cov kws tshawb fawb tau tsim, txhua yam ntawm cov tshuaj tiv thaiv saum toj no tuaj yeem nrog lub cev tshwm sim: kev tso tawm ntawm tshav kub lossis nws qhov nqus, emission ntawm photons ntawm lub teeb, kev hloov hauv lub xeev ntawm kev sib sau. Cov txheej txheem no tshwm sim hauv txhua lub plhaub ntawm lub ntiaj teb: lithosphere, hydrosphere, cua, biosphere. Qhov tseem ceeb tshaj plaws ntawm cov no yog cov voj voog ntawm cov khoom xws li oxygen, carbon dioxide thiab nitrogen. Nyob rau hauv nqe lus tom ntej, peb saib yuav ua li cas nitrogen circulates nyob rau hauv cov huab cua, av, thiabCov tsiaj muaj sia.
Kev hloov pauv ntawm nitrogen thiab nws cov tebchaw
Nws paub zoo tias nitrogen yog ib qho tseem ceeb ntawm cov proteins, uas txhais tau hais tias nws koom nrog hauv kev tsim txhua yam ntawm lub neej hauv ntiaj teb yam tsis muaj kev zam. Nitrogen yog absorbed los ntawm cov nroj tsuag thiab tsiaj nyob rau hauv daim ntawv ntawm ions: ammonium, nitrate thiab nitrite ions. Raws li qhov tshwm sim ntawm photosynthesis, cov nroj tsuag tsim tsis tsuas yog qabzib, tab sis kuj amino acids, glycerol, thiab fatty acids. Tag nrho cov tshuaj lom neeg saum toj no yog cov khoom ntawm cov tshuaj tiv thaiv tshwm sim hauv Calvin lub voj voog. Tus kws tshawb fawb Lavxias zoo tshaj K. Timiryazev tau hais txog lub luag haujlwm cosmic ntawm cov nroj tsuag ntsuab, xa mus, ntawm lwm yam, rau lawv lub peev xwm los tsim cov proteins.
Herbivores tau txais lawv cov peptides los ntawm cov zaub mov cog, thaum cov tsiaj txhu tau txais lawv cov peptides los ntawm cov nqaij nyug. Thaum lub sij hawm lwj ntawm cov nroj tsuag thiab tsiaj nyob rau hauv tus ntawm cov kab mob saprotrophic av, complex biological thiab tshuaj txheej txheem tshwm sim. Yog li ntawd, nitrogen los ntawm cov organic tebchaw kis mus rau hauv ib daim ntawv inorganic (ammonia, dawb nitrogen, nitrates thiab nitrites yog tsim). Rov qab mus rau qhov chaw thiab av, tag nrho cov tshuaj no rov qab los ntawm cov nroj tsuag. Nitrogen nkag mus rau hauv stomata ntawm daim tawv nqaij ntawm nplooj, thiab kev daws teeb meem ntawm nitric thiab nitrous acids thiab lawv cov ntsev yog absorbed los ntawm cov hauv paus plaub hau ntawm cov hauv paus hniav ntawm cov nroj tsuag. Lub voj voog ntawm nitrogen transformation kaw kom rov ua dua. Lub ntsiab ntawm cov txheej txheem tshuaj uas tshwm sim nrog nitrogen tebchaw nyob rau hauv cov xwm yog kawm nyob rau hauv nthuav dav thaum pib ntawm lub xyoo pua 20th los ntawm Lavxias teb sab kws tshawb fawb D. N. Pryanishnikov.
Powder Metallurgy
Cov txheej txheem tshuaj lom neeg niaj hnub thiab thev naus laus zis ua rau muaj txiaj ntsig zoo rau kev tsim cov khoom siv nrog lub cev thiab tshuaj lom neeg tshwj xeeb. Qhov no yog qhov tseem ceeb tshaj plaws, ua ntej ntawm tag nrho cov, rau cov cuab yeej thiab cov cuab yeej ntawm cov roj refineries, tuam txhab uas muag tsim inorganic acids, dyes, varnishes, thiab plastics. Hauv lawv cov khoom siv, cov khoom siv hluav taws xob sib txuas, cov khoom sib txuas, cov kab sib txuas, cov kav dej yog siv. Qhov saum npoo ntawm cov khoom siv yog nyob rau hauv kev sib cuag nrog aggressive media nyob rau hauv siab. Ntxiv mus, yuav luag tag nrho cov txheej txheem tshuaj lom neeg yog nqa tawm ntawm qhov kub thiab txias. Qhov cuam tshuam yog kev tsim cov khoom siv nrog tus nqi siab ntawm thermal thiab acid tsis kam, tiv thaiv corrosion.
hmoov metallurgy suav nrog kev tsim cov hmoov hlau uas muaj hlau, sintering thiab kev koom ua ke rau hauv cov hlau niaj hnub siv hauv kev cuam tshuam nrog cov tshuaj lom neeg.
Composites thiab lawv lub ntsiab lus
Ntawm cov thev naus laus zis niaj hnub no, cov txheej txheem tshuaj lom neeg tseem ceeb tshaj plaws yog cov tshuaj tiv thaiv ntawm kev tau txais cov khoom sib xyaw. Cov no muaj xws li foams, cermets, norpapalsts. Raws li ib tug matrix rau ntau lawm, hlau thiab lawv alloys, ceramics, thiab yas yog siv. Calcium silicate, av nplaum dawb, strontium thiab barium ferrides yog siv los ua fillers. Tag nrho cov khoom saum toj no muab cov ntaub ntawv sib xyaw cuam tshuam, kub thiab hnav tsis kam.
Yuav ua li cas yog chemical engineering
Cov ceg ntawm kev tshawb fawb uas kawm txog kev txhais tau tias thiab cov txheej txheem siv hauv kev cuam tshuam ntawm kev ua cov ntaub ntawv raw: roj, nkev, roj, thee, minerals, hu ua chemical technology. Hauv lwm lo lus, nws yog kev tshawb fawb ntawm cov txheej txheem tshuaj lom neeg tshwm sim los ntawm kev ua haujlwm ntawm tib neeg. Nws tag nrho theoretical puag yog tsim los ntawm kev ua lej, cybernetics, lub cev chemistry, thiab kev lag luam kev lag luam. Nws tsis muaj teeb meem dab tsi cov txheej txheem tshuaj koom nrog hauv cov thev naus laus zis (kom tau txais nitrate acid, decomposition ntawm limestone, synthesis ntawm phenol-formaldehyde plastics) - nyob rau hauv niaj hnub no nws yog tsis yooj yim sua yam uas tsis muaj automated tswj systems uas pab txhawb tib neeg kev ua ub no, tshem tawm ib puag ncig muaj kuab paug, thiab xyuas kom meej. Kev siv tshuab tsis tu ncua thiab pov tseg tsis muaj tshuaj lom neeg.
Nyob hauv daim ntawv no, peb tau txiav txim siab piv txwv ntawm cov txheej txheem tshuaj uas tshwm sim hauv cov tsiaj qus (photosynthesis, dissimilation, nitrogen voj voog) thiab hauv kev lag luam.
