蒸(zheng)汽(qi)壓滲透儀測(ce)量原(yuan)理(li):
連(lian)接不(bu)同(tong)測(ce)量的(de)兩(liang)個電熱(re)調節(jie)器懸(xuan)掛在恒溫測(ce)量池(chi)中,測(ce)量池(chi)充滿了溶(rong)劑(ji)的(de)飽(bao)和(he)蒸(zheng)汽(qi)。測(ce)量探頭初表面都覆(fu)蓋溶(rong)劑(ji)液(ye)滴,因而它們之間(jian)沒(mei)有(you)溫差。將壹個探頭表(biao)面的溶(rong)劑(ji)液(ye)滴換(huan)成(cheng)溶(rong)液(ye)液(ye)滴,由(you)於溶(rong)液(ye)表(biao)面更(geng)低(di)的溶(rong)劑(ji)蒸(zheng)氣(qi)壓,會導(dao)致溶(rong)劑(ji)蒸(zheng)氣(qi)冷凝。冷凝釋(shi)放的涵(han)使溶(rong)液(ye)液(ye)滴的(de)溫(wen)度(du)升高(gao),同(tong)時導(dao)致蒸(zheng)氣(qi)壓升高(gao)。當測(ce)量池(chi)和(he)溶(rong)液(ye)液(ye)滴表(biao)面的飽(bao)和(he)蒸(zheng)氣(qi)達到氣壓(ya)平(ping)衡時,溶(rong)液(ye)液(ye)滴達到壹個相對(dui)穩定的溫度(du),終導(dao)致兩(liang)個探頭的(de)溫(wen)度(du)不(bu)同(tong),溫度(du)差異(yi)直(zhi)接轉(zhuan)變(bian)成電壓信號。測(ce)量值(zhi)與(yu)溶(rong)液(ye)的(de)滲透濃(nong)度(du)成比例。
由於聚合(he)物溶(rong)液(ye)滲(shen)透壓(ya)與(yu)濃(nong)度(du)的非(fei)線(xian)性(xing)行(xing)為(wei),至少需要(yao)測(ce)量三(san)個濃(nong)度(du)梯(ti)度(du)的溶(rong)液(ye)。通過線(xian)形回歸的統計(ji)方法(fa)計(ji)算測(ce)量結(jie)果。
蒸(zheng)汽(qi)壓滲透儀的(de)檢(jian)測(ce)原(yuan)理(li)基(ji)於拉烏爾(er)定(ding)律(lv),即(ji)與(yu)溶(rong)液(ye)中(zhong)蒸(zheng)汽(qi)壓力的降(jiang)低有(you)關(guan)。在檢(jian)測(ce)池(chi)中彌(mi)散著溶(rong)劑(ji)蒸(zheng)汽(qi),兩(liang)個熱(re)敏(min)探頭 作(zuo)為(wei)惠(hui)斯通電橋(qiao)的的(de)兩(liang)個臂(bi),位(wei)於檢(jian)測(ce)池(chi)中。若(ruo)在兩(liang)個熱(re)敏(min)探頭上(shang)滴(di)入的均(jun)勻純溶(rong)劑(ji),則(ze)兩(liang)個熱(re)敏(min)探頭上(shang)的(de)電位(wei)為(wei)零。在檢(jian)測(ce)時,其中壹(yi)個熱(re)敏(min)探頭上(shang)的(de)液滴(di)被待(dai)測(ce)溶(rong)液(ye)滴(di)所(suo)代(dai)替,這(zhe)樣便導(dao)致蒸(zheng)汽(qi)壓力的下(xia)降(jiang)。於是,溶(rong)液(ye)的(de)蒸(zheng)汽(qi)凝聚在溶(rong)液(ye)的(de)液滴(di)上(shang),在與(yu)純溶(rong)劑(ji)液(ye)滴的(de)蒸(zheng)汽(qi)壓力相等(deng)時,溶(rong)液(ye)液(ye)滴的(de)蒸(zheng)汽(qi)壓會增加。
蒸(zheng)汽(qi)壓滲透儀產(chan)品(pin)特點(dian):
*測(ce)量系統自動調零
*自動(dong)控制測(ce)量室溫度(du)變化(hua)
*通過兩(liang)個高(gao)靈(ling)敏(min)度(du)的電(dian)熱(re)調節(jie)器測(ce)量溫(wen)差變(bian)化(hua)
*通過惠(hui)斯通電橋(qiao)顯(xian)示溫差(cha)變(bian)化(hua),靈(ling)敏(min)度(du)為(wei)5×10-5℃
*溫(wen)度(du)可從(cong)30℃調節(jie)到130℃,精(jing)度(du)為(wei)1℃,電(dian)熱(re)調節(jie)器適(shi)合(he)測(ce)量電(dian)導(dao)液
蒸(zheng)汽(qi)壓滲透儀基(ji)於純溶(rong)劑(ji)和(he)溶(rong)液(ye)之(zhi)間(jian)的(de)蒸(zheng)氣(qi)壓差原理(li)工(gong)作。將兩(liang)個經(jing)過仔(zai)細(xi)匹(pi)配的熱(re)敏(min)電(dian)阻(zu)放置在充(chong)滿溶(rong)劑(ji)蒸(zheng)氣(qi)的室內。將溶(rong)劑(ji)置(zhi)於兩(liang)個熱(re)敏(min)電(dian)阻(zu)上(shang)時,它(ta)們的溫度(du)相同(tong)。如果(guo)將溶(rong)液(ye)放在壹(yi)個熱(re)敏(min)電(dian)阻(zu)上(shang),則(ze)冷凝會加熱(re)該熱(re)敏(min)電(dian)阻(zu),直(zhi)到蒸(zheng)汽(qi)壓升至純溶(rong)劑(ji)的(de)蒸(zheng)汽(qi)壓為(wei)止(zhi)。溫度(du)的變(bian)化(hua)引(yin)起熱(re)敏(min)電(dian)阻(zu)的(de)電阻(zu)變(bian)化(hua)。電(dian)阻(zu)的(de)這(zhe)種(zhong)變化(hua)由(you)靈(ling)敏(min)的(de)橋(qiao)式電(dian)路(lu)測(ce)量,並(bing)顯(xian)示在面板儀表(biao),帶狀(zhuang)記(ji)錄儀和(he)/或計(ji)算機(ji)終端上(shang)。