儀器手動操作指南翻譯-中英對照
當使用儀器的手動標定功能時，按儀器的“▲”或“▼”鍵，使儀器顯示讀數(shù)與該緩沖溶液當時溫度下的pH值相一致(如用混合磷酸鹽定位溫度為10℃時，pH =6.92)，按儀器的“mV/pH/ENTER”鍵，儀器顯示該標準溶液在當時溫度下的pH值，然后儀器“斜率”符號閃耀，按儀器的“mV/pH/ENTER”鍵，儀器“斜率”符號消隱，儀器的一點標定完成，可以進行測量。
二點標定
(1) 按一點標定的方法進行第一點的標定，在儀器“斜率”符號閃耀時，表明儀器進入第二點標定狀態(tài)；
(2) 取出插在pH緩沖溶液中的電極，用蒸餾水清洗，把清洗過的電極插入另一種pH緩沖溶液中，同時利用電極輕輕攪拌，然后停止攪拌，輕輕地把電極置于溶液中，等待儀器的讀數(shù)穩(wěn)定，等待讀數(shù)穩(wěn)定；
(3) 當使用儀器的自動認知標定功能進行標定時，按儀器的“mV/pH/ENTER”鍵，儀器二點標定完成，自動進入測量狀態(tài)；
(4) 當使用儀器的手動功能時，按儀器的“▲”或“▼”鍵，使儀器顯示讀數(shù)與該緩沖溶液當時溫度下的pH值相一致(如用四硼酸鈉鹽標定溫度為10℃時，pH =9.33)，按儀器的“mV/pH/ENTER”鍵，儀器二點標定完成，自動進入測量狀態(tài)。
(5) 在第二點標定按“確認”后，如果儀器顯示“Er1”，時間大約4秒，然后儀器全屏顯示，之后進入pH測量狀態(tài)，表明儀器二點標定失敗，儀器會自動恢復到出廠時的參數(shù)。出現(xiàn)此現(xiàn)象有以下二個原因，第一，當使用自動認知標定功能時，由于pH復合電極的老化，其性能沒有達到規(guī)定的要求時，這時可以改用手動標定功能進行重新標定，如果還是出現(xiàn)“Er1”，說明電極已經(jīng)完全失效，這時必須更換電極，然后進行重新進行標定；第二，由于使用人員的誤操作，如使用了同一種標準溶液進行了二點標定或在手動標定時把第一種標準溶液誤認為第二種標準溶液時。
使用儀器進行pH值的測量
經(jīng)標定的儀器就可以進行pH值的測量（在不進行新的標定前儀器存儲最后一次標定的參數(shù)），但遇下列情況下，則儀器必須重新標定。
(1) 溶液溫度與標定時的溫度有很大的變化時；
(2) 離開溶液時間過久的電極；
(3) 換用了新的復合電極；
(4) 測量濃酸(pH<2)或濃堿(pH>12)之后；
(5) 測量含有氟化物的溶液而酸度在pH<7的溶液或較濃的有機溶液之后。
當被測溶液的溫度與標定時緩沖溶液溫度不同時，必須將溫度重新設置為被測溶液溫度，設置方法見儀器的溫度設定，即可測量溶液的pH值。
使用儀器進行電極電位(mV)值測量
(1) 按一下儀器的“電源”鍵接通電源，儀器即進入“pH”測量模式，再按一下儀器的“mV/pH/ENTER”鍵，儀器進入“mV”測量模式，就可以進行電極電位(mV)值測量；
(2) 接上各種適當?shù)碾x子選擇電極；
(3) 用蒸餾水清洗電極，用濾紙吸干；
(4) 把電極插在被測溶液內(nèi)，即可讀出該離子選擇電極的電極電位(mV值)并自動極性顯示。
儀器操作流程圖：
四、儀器的維護
儀器性能的好壞，除了儀器本身結構之外，與良好的維護是分不開的，特別是pH計這類儀器，它必須具有很高的輸入阻抗，而且使用環(huán)境經(jīng)常要接觸化學藥物，因此，合理的維護更有必要。
1． 儀器的輸入端（即復合電極插口）必須保持高度清潔，電極插頭不要經(jīng)常撥下，以防止灰塵及高濕浸入。
2． 復合電極的電極頭部很薄，因此，勿與硬物相碰，防止電極損壞。
3． 復合電極頭部勿接觸污物，如發(fā)現(xiàn)沾污可用醫(yī)用棉花輕擦電極頭部，或用0.1mol/L的稀鹽酸清洗。
4． 復合電極頭部裂紋或老化(久放一年以上)，則應調(diào)換新的電極，否則反應緩慢，甚至造成較大的測量誤差，新的電極在使用之前需在3mol/L氯化鉀溶液中浸泡24h。
5． 用緩沖溶液標定儀器時，要保證緩沖溶液的可靠性，因為緩沖溶液精度低，將導致測量結果的誤差，緩沖溶液可以自行配制，配制方法附后。
6． 請不要讓強烈陽光長時間直射液晶顯示器，以延長液晶顯示的使用壽命，必須防止硬物碰撞，劃傷顯示器表面玻璃。
7． 儀器長期不用請將電池取出。
附錄1：緩沖溶液的配制
1． pH4緩沖溶液(0.05mol/kg鄰苯二甲酸氫鉀溶液)，稱取(先在115℃±5℃下烘干 2h～3h的)鄰苯二甲酸氫鉀10.12g溶于蒸餾水，在容量瓶中稀釋至1000ml。
2． pH6.86緩沖溶液(0.025mol/kg磷酸二氫鉀和0.025mol/kg磷酸氫二鈉混合溶液)。分別稱取先在115℃±5℃下烘干 2h～3h的磷氫二鈉3.53g和磷酸二氫鉀3.39g溶于蒸餾水，在容量瓶中稀釋至1000ml。所用蒸餾水應預先煮沸15min～30min。
3． pH9緩沖溶液(0.01mol/kg硼砂鈉溶液)，稱取硼砂鈉3.80g(注意：不能烘)溶于蒸餾水，在容量瓶中稀釋至一升，蒸餾水應預先煮沸15min～30min。
附錄2：緩沖溶液的pH值與溫度關系對照表
溫度 緩沖溶液
℃ 0.05mol/kg
鄰苯二鉀酸氫鉀 0.025mol/kg
混合物磷酸鹽 0.01mol/kg
硼砂鈉
0 4.00 6.98 9.46
5 4.00 6.95 9.39
10 4.00 6.92 9.33
15 4.00 6.90 9.28
20 4.00 6.88 9.23
25 4.00 6.86 9.18
30 4.01 6.85 9.11
35 4.02 6.84 9.10
40 4.03 6.84 9.07
45 4.04 6.84 9.04
50 4.06 6.83 9.03
55 4.07 6.83 8.99
60 4.09 6.84 8.97
“mV/pH/ENTER”, which means the two-point calibration has been done and it enters into measuring state;
(4) After pressing “Enter” for calibration of the second point, if the instrument indicates “Er1” for about 4 seconds and the instrument switches to full screen display, then the instrument enters into pH measuring state, which indicates that two-point calibration is failed. The instrument will automatically return to parameters on leaving factory. There are two reasons for such phenomenon: firstly, when function of automatically cognitive calibration is applied, as the pH compound electrode is aging, its performance fails to satisfy requirement of standard, it is suggested to use function of manual calibration for re-calibrating; secondly, for the false operation performed by operator, if the same standard solution is applied for two-point calibration or regard the first standard solution as the second standard solution by mistake during manual calibration.
Measure pH value with instrument
The calibrated instrument can measure pH value (the instrument will store the parameters of calibration last time without implementing new calibration), but the instrument should be re-calibrated when following situations occurs:
(1) The temperature of solution changes a lot comparing with the temperature on calibration;
(2) The electrode has been out of solution for a long time;
(3) Replace a new compound electrode;
(4) After measuring concentrated acid (pH<2) or concentrated alkali (pH>12);
(5) After measuring solution which contains fluoride with the acidity pH<7 or concentrated organic solution.
When the temperature of tested solution is different from that of buffer solution during calibration, the temperature must be reset to that of tested solution, see temperature setting of instrument for the setting method, and then it is possible to measure pH value of solution.
Measure electrode potential (mV) value with instrument
(1) Press key “Power supply”on instrument to switch on and the instrument enters into “pH”measuring mode, and then press key“mV/pH/ENTER”, the instrument enters into“mV”measuring mode, then measurement on electrode potential (mV) value is available;
(2) .Connect various ion selective electrodes which are suitable;
(3) Rinse the electrode with distilled water and dry it with filter paper;
(4) Insert electrode into tested solution to read the electrode potential (mV value) of this ion selective electrode, with automatic polar display.
The operation flow chart for the instrument
IV. Maintenance of Instrument
The performance of instrument depends on its own structure as well as good maintenance, especially for pH instrument, which requires high input impedance and reasonable maintenance for it frequently contacts chemical substances.
1. The input terminal of instrument (namely, socket of compound electrode) must be kept clean and do not pull the plug frequently to prevent dust and high humidity from immerging.
2. The electrode tip of compound electrode is rather thin, thus collision with hard object should be avoided for fear of any damage to electrode.
3. Keep the compound electrode tip away from pollutant, and slightly wipe the electrode trip with medical cotton or rinse it with 0.1mol/L dilute hydrochloric acid if it is polluted.
4. If crack or aging occurs on compound electrode tip (being stored for over one year), replace it with a new electrode, or the reaction will be quite slow or serious measuring error will be caused. Before applying a new electrode, it must be immersed into 3mol/L potassium chloride solution for 24h.
5. On calibrating instrument with buffer solution, the reliability of buffer solution shall be ensured, because the buffer solution with low precision will lead to error of measuring result. The preparation of buffer solution is available with the method being attached.
6. Please do not expose the LCD (liquid crystal display) to sunlight directly in order to prolong the service life of LCD, avoiding collision with hard object which may scratch the glass surface of display.
7. Remove the battery of instrument for long-term storage without using it.
Appendix 1: Preparation of Buffer Solution
1. pH4 buffer solution (0.05mol/kg potassium hydrogen phthalate solution), weigh 10.12g potassium hydrogen phthalate (which has been dried for 2h～3h at a temperature of 115℃±5℃) and dissolve it in distilled water, and then dilute it to 1000ml in a volumetric flask.
2. PH6.86 buffer solution (mixed solution of 0.025mol/kg potassium dihydrogen phosphate and 0.025mol/kg disodium hydrogen phosphate). Respectively weigh 3.53g disodium hydrogen phosphate and 3.39g potassium dihydrogen phosphate which have been dried for 2h～3h at a temperature of 115℃±5℃ and dissolve them in distilled water, and then dilute them to 1000ml in a volumetric flask. The distilled water should be boiled for 15min～30min in advance.
3. pH9 buffer solution (0.01mol/kg sodium borate solution), weigh 3.80g sodium borate (remarks: no drying) and dissolve it in distilled water, and then dilute it to 1000L in a volumetric flask.
Appendix 2. Contrast forms in relation between pH value and temperature of the buffer solution
Temperature Buffer Solution
℃ 0.05mol/kg
Potassium Acid Phthalate (KAP 0.025mol/kg
Admixture of phosphate 0.01mol/kg
Borax sodium
2013.3.10