低溫等(deng)(deng)離(li)子(zi)(zi)體(ti)是繼固態(tai)、液(ye)態(tai)、氣態(tai)之后的物(wu)質(zhi)第(di)四態(tai),當外加電壓(ya)達(da)到氣體(ti)的著火電壓(ya)時,氣體(ti)分子(zi)(zi)被擊穿,產(chan)生包(bao)括電子(zi)(zi)、各種(zhong)離(li)子(zi)(zi)、原子(zi)(zi)和自由基在內(nei)的混合體(ti)。低溫等(deng)(deng)離(li)子(zi)(zi)體(ti)放(fang)電過(guo)程中雖(sui)然電子(zi)(zi)溫度(du)很高,但重粒子(zi)(zi)溫度(du)很低,整個(ge)體(ti)系呈(cheng)現低溫狀(zhuang)態(tai),所以稱為低溫等(deng)(deng)離(li)子(zi)(zi)體(ti),也叫非平衡(heng)態(tai)等(deng)(deng)離(li)子(zi)(zi)體(ti)。
如(ru)果(guo)電子(zi)(zi)的溫(wen)度和重粒(li)子(zi)(zi)溫(wen)度差(cha)不(bu)多,則(ze)為高溫(wen)等離子(zi)(zi)體(ti),或平衡(heng)態等離子(zi)(zi)體(ti)。
低(di)溫等(deng)(deng)離子(zi)(zi)(zi)(zi)(zi)(zi)體(ti)中能(neng)(neng)量(liang)的(de)(de)(de)(de)傳遞大(da)致(zhi)為:電(dian)(dian)(dian)子(zi)(zi)(zi)(zi)(zi)(zi)從電(dian)(dian)(dian)場(chang)中得到(dao)能(neng)(neng)量(liang),通(tong)(tong)過碰撞(zhuang)(zhuang)將(jiang)能(neng)(neng)量(liang)轉化為分子(zi)(zi)(zi)(zi)(zi)(zi)的(de)(de)(de)(de)內(nei)能(neng)(neng)和(he)(he)動能(neng)(neng),獲(huo)得能(neng)(neng)量(liang)的(de)(de)(de)(de)分子(zi)(zi)(zi)(zi)(zi)(zi)被激(ji)發,與(yu)此同時(shi),部分分子(zi)(zi)(zi)(zi)(zi)(zi)被電(dian)(dian)(dian)離,這(zhe)些(xie)活(huo)化了(le)的(de)(de)(de)(de)粒子(zi)(zi)(zi)(zi)(zi)(zi)相互碰撞(zhuang)(zhuang)從而(er)(er)引(yin)起一系(xi)列復雜的(de)(de)(de)(de)物(wu)(wu)理化學(xue)(xue)反應(ying)。因(yin)等(deng)(deng)離子(zi)(zi)(zi)(zi)(zi)(zi)體(ti)內(nei)富含的(de)(de)(de)(de)大(da)量(liang)活(huo)性粒子(zi)(zi)(zi)(zi)(zi)(zi)如離子(zi)(zi)(zi)(zi)(zi)(zi)、電(dian)(dian)(dian)子(zi)(zi)(zi)(zi)(zi)(zi)、激(ji)發態的(de)(de)(de)(de)原子(zi)(zi)(zi)(zi)(zi)(zi)和(he)(he)分子(zi)(zi)(zi)(zi)(zi)(zi)及自由(you)基等(deng)(deng),從而(er)(er)為等(deng)(deng)離子(zi)(zi)(zi)(zi)(zi)(zi)體(ti)技術通(tong)(tong)過化學(xue)(xue)反應(ying)處理異(yi)味(wei)物(wu)(wu)質提(ti)供(gong)了(le)條件。它是基于放(fang)(fang)電(dian)(dian)(dian)物(wu)(wu)理、放(fang)(fang)電(dian)(dian)(dian)化學(xue)(xue)、反應(ying)工(gong)程學(xue)(xue)的(de)(de)(de)(de)學(xue)(xue)科之(zhi)上的(de)(de)(de)(de)交叉(cha)學(xue)(xue)科。近幾十年來,有關等(deng)(deng)離子(zi)(zi)(zi)(zi)(zi)(zi)體(ti)技術的(de)(de)(de)(de)研究非常(chang)活(huo)躍,為合成新(xin)(xin)物(wu)(wu)質、新(xin)(xin)材料(liao)及環境污染(ran)(ran)治理等(deng)(deng)提(ti)供(gong)了(le)一種新(xin)(xin)技術、新(xin)(xin)方法和(he)(he)新(xin)(xin)工(gong)藝。低(di)溫等(deng)(deng)離子(zi)(zi)(zi)(zi)(zi)(zi)體(ti)降(jiang)解(jie)(jie)污染(ran)(ran)物(wu)(wu)是利用(yong)這(zhe)些(xie)高(gao)能(neng)(neng)電(dian)(dian)(dian)子(zi)(zi)(zi)(zi)(zi)(zi)、自由(you)基等(deng)(deng)活(huo)性粒子(zi)(zi)(zi)(zi)(zi)(zi)和(he)(he)廢氣中的(de)(de)(de)(de)污染(ran)(ran)物(wu)(wu)作用(yong),使污染(ran)(ran)物(wu)(wu)分子(zi)(zi)(zi)(zi)(zi)(zi)在(zai)短的(de)(de)(de)(de)時(shi)間內(nei)發生分解(jie)(jie),并發生后續的(de)(de)(de)(de)各種反應(ying)以達到(dao)降(jiang)解(jie)(jie)污染(ran)(ran)物(wu)(wu)的(de)(de)(de)(de)目的(de)(de)(de)(de)。但是,無論(lun)是哪一種高(gao)壓放(fang)(fang)電(dian)(dian)(dian)技術,都是通(tong)(tong)過高(gao)壓放(fang)(fang)電(dian)(dian)(dian)的(de)(de)(de)(de)原理,充分考(kao)慮到(dao)爆炸問題,特別是在(zai)易(yi)燃易(yi)爆的(de)(de)(de)(de)化工(gong)場(chang)合。
狀態解釋(shi)
冰升溫(wen)至(zhi)0℃會(hui)變成水(shui)(shui),如繼續(xu)使溫(wen)度(du)(du)升至(zhi)100℃,那么水(shui)(shui)就會(hui)沸騰(teng)成為(wei)水(shui)(shui)蒸氣。隨(sui)著溫(wen)度(du)(du)的(de)(de)(de)上升,物(wu)(wu)質(zhi)(zhi)的(de)(de)(de)存(cun)在狀(zhuang)態一(yi)般會(hui)呈現出固態→液態→氣態三(san)種物(wu)(wu)態的(de)(de)(de)轉(zhuan)化(hua)過(guo)程,我們(men)把這三(san)種基本形態稱為(wei)物(wu)(wu)質(zhi)(zhi)的(de)(de)(de)三(san)態。那么對(dui)于氣態物(wu)(wu)質(zhi)(zhi),溫(wen)度(du)(du)升至(zhi)幾千度(du)(du)時(shi),將會(hui)有什么新變化(hua)呢? 由(you)于物(wu)(wu)質(zhi)(zhi)分(fen)子(zi)(zi)熱運動(dong)加劇(ju),相互間的(de)(de)(de)碰撞就會(hui)使氣體(ti)(ti)分(fen)子(zi)(zi)產生電(dian)離(li)(li),這樣物(wu)(wu)質(zhi)(zhi)就變成由(you)自(zi)由(you)運動(dong)并相互作(zuo)用的(de)(de)(de)正(zheng)離(li)(li)子(zi)(zi)和(he)電(dian)子(zi)(zi)組成的(de)(de)(de)混合(he)物(wu)(wu)(蠟燭的(de)(de)(de)火焰(yan)就處(chu)于這種狀(zhuang)態)。我們(men)把物(wu)(wu)質(zhi)(zhi)的(de)(de)(de)這種存(cun)在狀(zhuang)態稱為(wei)物(wu)(wu)質(zhi)(zhi)的(de)(de)(de)第(di)四(si)態,即(ji)等(deng)(deng)(deng)(deng)離(li)(li)子(zi)(zi)體(ti)(ti)(plasma)。因為(wei)電(dian)離(li)(li)過(guo)程中正(zheng)離(li)(li)子(zi)(zi)和(he)電(dian)子(zi)(zi)總(zong)是成對(dui)出現,所以等(deng)(deng)(deng)(deng)離(li)(li)子(zi)(zi)體(ti)(ti)中正(zheng)離(li)(li)子(zi)(zi)和(he)電(dian)子(zi)(zi)的(de)(de)(de)總(zong)數大(da)致(zhi)相等(deng)(deng)(deng)(deng),總(zong)體(ti)(ti)來看為(wei)準電(dian)中性。反過(guo)來,我們(men)可以把等(deng)(deng)(deng)(deng)離(li)(li)子(zi)(zi)體(ti)(ti)定義為(wei):正(zheng)離(li)(li)子(zi)(zi)和(he)電(dian)子(zi)(zi)的(de)(de)(de)密度(du)(du)大(da)致(zhi)相等(deng)(deng)(deng)(deng)的(de)(de)(de)電(dian)離(li)(li)氣體(ti)(ti)。
產生(sheng)方法
輝光放(fang)(fang)(fang)電(dian)(dian),電(dian)(dian)暈放(fang)(fang)(fang)電(dian)(dian),介質阻(zu)擋(dang)放(fang)(fang)(fang)電(dian)(dian),射(she)頻放(fang)(fang)(fang)電(dian)(dian),滑動電(dian)(dian)弧(hu)放(fang)(fang)(fang)電(dian)(dian),射(she)流放(fang)(fang)(fang)電(dian)(dian),大(da)氣壓(ya)輝光放(fang)(fang)(fang)電(dian)(dian),次(ci)大(da)氣壓(ya)輝光放(fang)(fang)(fang)電(dian)(dian)
輝光放(fang)電(GlowDischarge)
輝(hui)光(guang)放電(dian)(dian)(dian)屬于(yu)低(di)氣(qi)(qi)(qi)壓放電(dian)(dian)(dian)(low pressure discharge),工(gong)作壓力一般(ban)都低(di)于(yu)10mbar,其(qi)構造是在封(feng)閉(bi)的(de)(de)容器(qi)內(nei)放置兩(liang)個平行的(de)(de)電(dian)(dian)(dian)板(ban),利用(yong)電(dian)(dian)(dian)子將中性原(yuan)子和(he)分子激發(fa),當粒子由激發(fa)態(excited state)降回至基態(ground state)時會以光(guang)的(de)(de)形式(shi)釋(shi)放出能量。電(dian)(dian)(dian)源可(ke)以為(wei)直流(liu)電(dian)(dian)(dian)源也可(ke)以是交流(liu)電(dian)(dian)(dian)源。每種氣(qi)(qi)(qi)體都有(you)(you)其(qi)典型的(de)(de)輝(hui)光(guang)放電(dian)(dian)(dian)顏(yan)色(se)(如下(xia)表所示),熒光(guang)燈的(de)(de)發(fa)光(guang)即為(wei)輝(hui)光(guang)放電(dian)(dian)(dian)。因(yin)(yin)此(ci),實驗(yan)時若發(fa)現等(deng)離子的(de)(de)顏(yan)色(se)有(you)(you)誤,通常代表氣(qi)(qi)(qi)體的(de)(de)純度(du)有(you)(you)問題,一般(ban)為(wei)漏氣(qi)(qi)(qi)所至。輝(hui)光(guang)放電(dian)(dian)(dian)是化學等(deng)離子體實驗(yan)的(de)(de)重要(yao)工(gong)具,但因(yin)(yin)其(qi)受(shou)低(di)氣(qi)(qi)(qi)壓的(de)(de)限(xian)制,工(gong)業(ye)應(ying)用(yong)難于(yu)連續(xu)化生(sheng)產且(qie)應(ying)用(yong)成本高(gao)昂,而無法廣泛(fan)應(ying)用(yong)于(yu)工(gong)業(ye)制造中。到(dao)2013年止的(de)(de)應(ying)用(yong)范圍僅(jin)局限(xian)于(yu)實驗(yan)室、燈光(guang)照明產品和(he)半(ban)導體工(gong)業(ye)等(deng)[1] 。