Poly(diallyldimethylammonium chloride)(PDDA)is used as organic coagulant in water purification and auxiliary agent in paper production.Determination of PDDA in aqueous solutions is carried out usually by means of poly...Poly(diallyldimethylammonium chloride)(PDDA)is used as organic coagulant in water purification and auxiliary agent in paper production.Determination of PDDA in aqueous solutions is carried out usually by means of polyelectrolyte titration using streaming current detector or o-Toluidine Blue dye for endpoint recognition.The proposed method of PDDA assay takes advantage of Coomassie Brilliant Blue G dye having strong affinity to cationic macromolecules.Titration of PDDA solution with the dye is carried out measuring absorbance at 585nm.Inflection points of the obtained zigzag photometric curves have good repeatability provided that titration rate is low enough to attain endpoint for 1hour or more.The method assures rectilinear calibration(R2=0.999 5)in the broad range of PDDA concentrations from 0.3to 9.6mg·dm^(-3).展开更多
The paper presents a new method of determining Ge in gold alloys by potassium iodate potentiometric titration rather than by traditional distillation separation. The influences of conditions such as the reduction acid...The paper presents a new method of determining Ge in gold alloys by potassium iodate potentiometric titration rather than by traditional distillation separation. The influences of conditions such as the reduction acidity, dosage of sodium hypophosphite and reduction time on the determination of Ge were studied. Comparison was made between the influences of end-point indication for potential method and starch method on accruracy and precision of the analysed results, stability and sensitivity of end-point, selectivity of method and so on. The possibility of reaction in an electrochemical way was discussed. Ge in the alloys such as AuGe 12 , AuGeNi 12 2 , AuAgGe 18.8 12.5 and AuAgGeNi 43.8 6 0.2 was measured, respectively, with the relative standard deviation of 0.10%~0.31% and the recoveries of added standard Ge in sample of 99.40%～100.40% when the reduction acidity was 0.40~0.80 mol/L HCl and 3.3 mol/L H 3 PO 4, 15 g sodium hypophosphite and reduction time 40 min. The new method presented is high accuracy and precision in results, good stability and sensibility in end point, easy operation and strong selectivity of determination. When it is applied to analyse actual samples, satisfactory results are achieved.展开更多
10001 A Precise Coulometric Titration Method forthe Determination of Purity of Sodium Carbonate.Tang Gaohua,Lin Dawei: 1(2). 1980. pp.142--146.This paper describes the method artd device of precisecoulometric titratio...10001 A Precise Coulometric Titration Method forthe Determination of Purity of Sodium Carbonate.Tang Gaohua,Lin Dawei: 1(2). 1980. pp.142--146.This paper describes the method artd device of precisecoulometric titration at constant current for thedetermination of purity of sodium carbonate. The con-ditions of measurement are stated in detail. By thismethod. the attainable precision is 0.004%. and thetotal uncertainty is 0.005%.展开更多
The capacity intermittent titration technique (CITT) was developed based on the ratio of potentio-charge capacity to galvano-charge capacity (RPG) method, to continuously determine the solid diffusion coefficient (D) ...The capacity intermittent titration technique (CITT) was developed based on the ratio of potentio-charge capacity to galvano-charge capacity (RPG) method, to continuously determine the solid diffusion coefficient (D) of the intercalary species within insertion-host materials with a small voltage region. The linear equations of D vs the value of ratio of the potentio-charge capacity to the galvano-charge capacity (q) were given. By the CITT technique,the Li+ solid diffusion coefficients within LiMn2 O4 at different voltages were determined. The results show that the values of D varied from 3. 447× 10-9 to 7.60× 10-11 cm2/s in the voltage range of charge from 3.3 to 4.3 V as a function of voltage with "W" shape.展开更多
文摘Poly(diallyldimethylammonium chloride)(PDDA)is used as organic coagulant in water purification and auxiliary agent in paper production.Determination of PDDA in aqueous solutions is carried out usually by means of polyelectrolyte titration using streaming current detector or o-Toluidine Blue dye for endpoint recognition.The proposed method of PDDA assay takes advantage of Coomassie Brilliant Blue G dye having strong affinity to cationic macromolecules.Titration of PDDA solution with the dye is carried out measuring absorbance at 585nm.Inflection points of the obtained zigzag photometric curves have good repeatability provided that titration rate is low enough to attain endpoint for 1hour or more.The method assures rectilinear calibration(R2=0.999 5)in the broad range of PDDA concentrations from 0.3to 9.6mg·dm^(-3).
基金The National High Technology Research and Development Program of China(2012AA063203,2012AA063207)Research Foundation of Kunming Institute of Precious Metals(GY08RD27)
文摘The paper presents a new method of determining Ge in gold alloys by potassium iodate potentiometric titration rather than by traditional distillation separation. The influences of conditions such as the reduction acidity, dosage of sodium hypophosphite and reduction time on the determination of Ge were studied. Comparison was made between the influences of end-point indication for potential method and starch method on accruracy and precision of the analysed results, stability and sensitivity of end-point, selectivity of method and so on. The possibility of reaction in an electrochemical way was discussed. Ge in the alloys such as AuGe 12 , AuGeNi 12 2 , AuAgGe 18.8 12.5 and AuAgGeNi 43.8 6 0.2 was measured, respectively, with the relative standard deviation of 0.10%~0.31% and the recoveries of added standard Ge in sample of 99.40%～100.40% when the reduction acidity was 0.40~0.80 mol/L HCl and 3.3 mol/L H 3 PO 4, 15 g sodium hypophosphite and reduction time 40 min. The new method presented is high accuracy and precision in results, good stability and sensibility in end point, easy operation and strong selectivity of determination. When it is applied to analyse actual samples, satisfactory results are achieved.
基金supported by the National Natural Science Foundation of China(6127509961371164)+2 种基金the Natural Science Foundation of Chongqing(CSTC2012JJA40008)the Research Project of Chongqing Educational Commission(KJ120525KJ130524)
文摘10001 A Precise Coulometric Titration Method forthe Determination of Purity of Sodium Carbonate.Tang Gaohua,Lin Dawei: 1(2). 1980. pp.142--146.This paper describes the method artd device of precisecoulometric titration at constant current for thedetermination of purity of sodium carbonate. The con-ditions of measurement are stated in detail. By thismethod. the attainable precision is 0.004%. and thetotal uncertainty is 0.005%.
基金Project (20406024) supported by the National Natural Science Foundation of China project (76600) supported by the Postdoctoral Science Foundation of Central South University
文摘The capacity intermittent titration technique (CITT) was developed based on the ratio of potentio-charge capacity to galvano-charge capacity (RPG) method, to continuously determine the solid diffusion coefficient (D) of the intercalary species within insertion-host materials with a small voltage region. The linear equations of D vs the value of ratio of the potentio-charge capacity to the galvano-charge capacity (q) were given. By the CITT technique,the Li+ solid diffusion coefficients within LiMn2 O4 at different voltages were determined. The results show that the values of D varied from 3. 447× 10-9 to 7.60× 10-11 cm2/s in the voltage range of charge from 3.3 to 4.3 V as a function of voltage with "W" shape.
