引起離(li)子在被(bei)測(ce)(ce)溶(rong)(rong)液中(zhong)(zhong)運動的(de)(de)電(dian)(dian)(dian)(dian)(dian)場是由(you)(you)與溶(rong)(rong)液直(zhi)接接觸(chu)的(de)(de)二(er)個電(dian)(dian)(dian)(dian)(dian)極(ji)產生的(de)(de)。此對測(ce)(ce)量(liang)(liang)電(dian)(dian)(dian)(dian)(dian)極(ji)必須(xu)由(you)(you)抗(kang)化學腐蝕的(de)(de)材(cai)料(liao)制成。實際(ji)中(zhong)(zhong)經(jing)常用(yong)到(dao)(dao)的(de)(de)材(cai)料(liao)有鈦(tai)等(deng)。由(you)(you)二(er)個電(dian)(dian)(dian)(dian)(dian)極(ji)組成的(de)(de)測(ce)(ce)量(liang)(liang)電(dian)(dian)(dian)(dian)(dian)極(ji)被(bei)稱為(wei)爾(er)勞施電(dian)(dian)(dian)(dian)(dian)極(ji)。電(dian)(dian)(dian)(dian)(dian)導率的(de)(de)測(ce)(ce)量(liang)(liang)需要弄(nong)清(qing)兩方(fang)面。一(yi)個是溶(rong)(rong)液的(de)(de)電(dian)(dian)(dian)(dian)(dian)導，另一(yi)個是溶(rong)(rong)液中(zhong)(zhong)1/A的(de)(de)幾何關系，電(dian)(dian)(dian)(dian)(dian)導可以(yi)通過電(dian)(dian)(dian)(dian)(dian)流、電(dian)(dian)(dian)(dian)(dian)壓的(de)(de)測(ce)(ce)量(liang)(liang)得到(dao)(dao)。這一(yi)測(ce)(ce)量(liang)(liang)原理(li)在當今直(zhi)接顯示測(ce)(ce)量(liang)(liang)儀表(biao)中(zhong)(zhong)得到(dao)(dao)應用(yong)。
下面和大家分享一下粉末電導率測試儀是如何使用哦。
1、未開(kai)電源開(kai)關(guan)前，觀察表針是否指零(ling)，可調正表頭上的螺絲，使表針指零(ling)。
2、將校正(zheng)測量開關扳在“校正(zheng)”位置。
3、插(cha)接電(dian)源線，打開電(dian)源開關，并(bing)預熱(re)數分(fen)鐘(zhong)(待指(zhi)針*穩定下來(lai)為止(zhi))調節(jie)“調正”調節(jie)器使(shi)電(dian)表指(zhi)示滿度(du)。
4、當使用(1)-(8)量程(cheng)(cheng)來測(ce)量電(dian)導率(lv)低(di)于300μS.cm-1的(de)液體時，選用“低(di)周”，這時將高/低(di)周開關扳(ban)(ban)向低(di)周即可。當使用(9)-(10)量程(cheng)(cheng)來測(ce)量電(dian)導率(lv)在300μS.cm-1至105μS.cm-1范圍里的(de)液體時，則將扳(ban)(ban)向“高周”。
5、將量(liang)(liang)程(cheng)選擇開關扳到所(suo)需要的測量(liang)(liang)范圍(wei)，如(ru)預先不知被測溶液(ye)電(dian)導(dao)率大(da)小，應先把其(qi)扳到zui大(da)電(dian)導(dao)率測量(liang)(liang)檔(dang)，然后(hou)逐漸(jian)下降(jiang)，以防表針打彎。
6、電(dian)(dian)極的使用(yong)：使用(yong)時用(yong)電(dian)(dian)極夾夾緊電(dian)(dian)極的膠木帽，并把電(dian)(dian)極夾固定在電(dian)(dian)極桿上。
7、將(jiang)電極插頭插入(ru)電極插口內，旋緊(jin)插口上(shang)的緊(jin)固螺絲，再將(jiang)電極綅入(ru)待測溶液中。
8、接著校(xiao)(xiao)正(zheng)[當用(yong)(1)-(8)量程(cheng)測量時，校(xiao)(xiao)正(zheng)時扳到(dao)低(di)周，當用(yong)(9)-(12)量程(cheng)測量時，則校(xiao)(xiao)正(zheng)扳到(dao)高周]，扳到(dao)“校(xiao)(xiao)正(zheng)”，調節校(xiao)(xiao)正(zheng)調節器，使指(zhi)示在(zai)滿度(du)。
9、當(dang)用(0-0.1)或(0-0.3)μS.cm-1這兩檔測量高純水時，先把(ba)電(dian)(dian)極(ji)引線插入電(dian)(dian)極(ji)插孔，在電(dian)(dian)極(ji)未綅入溶液(ye)前，調節(jie)電(dian)(dian)容(rong)補償調節(jie)器使電(dian)(dian)表指(zhi)示為zui小值(zhi)(zhi)(此zui小值(zhi)(zhi)即電(dian)(dian)極(ji)鉑片間的漏(lou)電(dian)(dian)阻，由于此漏(lou)電(dian)(dian)阻的存在，使得調電(dian)(dian)容(rong)補償調節(jie)器時電(dian)(dian)表指(zhi)針不(bu)能達到零點)。
電導的基本單位(wei)是西門子(S)，原(yuan)來被稱為姆(mu)歐(ou)，取電阻(zu)單位(wei)歐(ou)姆(mu)倒數之意。因為電導池的幾何形狀影響電導率值，所以(yi)標準(zhun)的測量中用單位(wei)S/cm來表(biao)示電導率，以(yi)補償各種電極尺寸造成的差別。
單位電(dian)(dian)(dian)導(dao)(dao)率(lv)(C)簡單的(de)說是所測電(dian)(dian)(dian)導(dao)(dao)(G)與電(dian)(dian)(dian)導(dao)(dao)池常數(L/A)的(de)乘積(ji).這里的(de)L為(wei)兩塊極板之間的(de)液柱長度，A為(wei)極板的(de)面積(ji)。=ρl=l/σ(1)定義或解(jie)釋電(dian)(dian)(dian)阻(zu)率(lv)的(de)倒數為(wei)電(dian)(dian)(dian)導(dao)(dao)率(lv)。σ=1/ρ;(2)單位:在單位制(zhi)中(zhong),電(dian)(dian)(dian)導(dao)(dao)率(lv)的(de)單位是西門(men)子/米,其它單位有：s/cm，us/cm。1S/m=0.01s/cm=10000us/cm;(3)說明電(dian)(dian)(dian)導(dao)(dao)率(lv)的(de)物(wu)理意義是表示物(wu)質導(dao)(dao)電(dian)(dian)(dian)的(de)性能(neng)。電(dian)(dian)(dian)導(dao)(dao)率(lv)越大則導(dao)(dao)電(dian)(dian)(dian)性能(neng)越強，反之越小(xiao)。
