scholarly journals SPECTROPHOTOMETRIC DETERMINATION OF PYROCATHECOL AND PYROGALLOL BASED ON THEIR REDOX REACTION WITH IRON(III)/PHENANTHROLINE SYSTEM

2010 ◽  
Vol 2 (3) ◽  
pp. 161-166 ◽  
Author(s):  
Mudasir Mudasir ◽  
Mugiyanti Mugiyanti ◽  
Ngatidjo Hadipranoto
Keyword(s):  
Phenolic Compounds ◽  
Redox Reaction ◽  
Heating Temperature ◽  
Heating Time ◽  
Maximum Absorption ◽  
Optimum Conditions ◽  
Phenanthroline Complex ◽  
Maximum Absorption Wavelength ◽  
Absorption Wavelength

An analytical method for the spectrophotometric determination of some phenolic compounds, i.e.: pyrocathecol and pyrogallol based on their redox reaction with iron(III)-phenanthroline complex has been developed. These two compounds, in appropriate conditions, reduce iron(III)-phenanthroline complex to yield very stable and color-intense complex of iron(II)-phenanthroline, [Fe(phen)2]2+, whose concentration is equivalent to the amount of pyrocathecol or pyrogallol in the solution, and is easily detected by spectrophotometric method. Some parameters influencing the sensitivity of the determination were optimized. These included maximum absorption wavelength, pH of the solution, time and temperature of heatingand reagent to analyte minimum mole-ratio. Using the optimum conditions obtained, the analytical performance of the method was examined and the developed method was then applied to analyzed pyrocathecol and pyrogallol contents in several river water of Yogyakarta, Indonesia. Result of the study showed that the optimum conditions for the determination of pyrocathecol are as follows: maximum absorption wavelength (lmax) at 510 nm, pH of the solution = 4, heating time = 120 min, heating temperature = 70 0C and the minimum mole ratio of reagent to analyte is 8. On the other hand, the optimum conditions for the determination of pyrogallol are as follows: maximum absorption wavelength (lmax) at 510 nm, pH of the solution = 5, heating time = 90 min, heating temperature = 90 0C and the minimum mole ratio of reagent to analyte is 7. At the corresponding conditions of analysis, calibration curves for pyrocathecol and pyrogallol are linear in the range concentration of 0.00 - 0.16 ppm and 0.00 - 0.24 ppm, respectively. The correlation coefficients for both compounds were found to be higher than 0.998 and the detection limits went down below 0.07 ppm. It has been demonstrated that the developed method can be applied for the determination of pyrocathecol and pyrogallol contents in natural samples.   Keywords: Spectrophotometry, phenolic compounds, 1,10-phenanthroline, redox reaction

Study on Determination of Glucose in Amylofermentation Liquid Using Ultraviolet Spectrophotometry

2012 ◽  
Vol 538-541 ◽  
pp. 2434-2437 ◽  
Author(s):  
Bao Shan He ◽  
Na Gao ◽  
Fang Wei ◽  
Qi Yu Lu
Keyword(s):  
Hydrogen Peroxide ◽  
Glucose Oxidase ◽  
Optical Method ◽  
Maximum Absorption ◽  
Ultraviolet Spectrophotometry ◽  
Titanyl Oxalate ◽  
Maximum Absorption Wavelength ◽  
Absorption Wavelength

In the presence of glucose oxidase, glucose in samples was oxygenated to hydrogen peroxide, the solution turned from colourless to yellow upon the reaction of potassium titanyl oxalate to the generated hydrogen peroxide. Using ultraviolet spectrophotometry, a new optical method for detecting glucose in amylofermentation liquid has been established. Results demonstrated that glucose concentrations were proportional to absorbance at the maximum absorption wavelength of 380 nm. A favorable linearity was presented in the range of 1 mmol/L to 60 mmol/L. The linear coeffciency was 0.993. This method was simple, reliable, and could be used for determing glucose in samples.

Ammonium removal from wastewater via struvite pyrolysate recycling with Mg(OH)2 addition

2013 ◽  
Vol 68 (12) ◽  
pp. 2661-2667 ◽  
Author(s):  
Rongtai Yu ◽  
Subin Cheng ◽  
Hongqiang Ren ◽  
Yanru Wang ◽  
Lili Ding ◽  
...  
Keyword(s):  
Heating Temperature ◽  
Ammonium Phosphate ◽  
Heating Time ◽  
Phosphate Concentration ◽  
Molar Ratio ◽  
Optimum Conditions ◽  
Magnesium Ammonium Phosphate ◽  
Ammonium Removal ◽  
Ammonia Release ◽  
Magnesium Ammonium

Magnesium ammonium phosphate (MAP) pyrolysate recycling technology was investigated with Mg(OH)2-mediated pyrolysis. The results revealed that the removal ratio of ammonium was stable at about 75%, and could be increased to 79% after additional acidolysis. The phosphate concentration in the supernate was low at 2 mg/L. The optimum conditions for ammonia release were a 1:1 molar ratio of Mg(OH)2:NH4+, a heating temperature of 110 °C and a heating time of 3 h. With continual additions of Mg(OH)2 to release ammonia, magnesium phosphate (Mg3(PO4)2) was suggested as a possible derivative. However, with Mg(OH)2-mediated pyrolysis, the growth and nucleation of MAP was inhibited during MAP pyrolysate recycling.

Spectrophotometric determination of peroxymonosulfate anions via oxidative decolorization of dyes induced by cobalt

2016 ◽  
Vol 8 (5) ◽  
pp. 973-978 ◽  
Author(s):  
J. Q. Zhang ◽  
J. Ma ◽  
J. Zou ◽  
H. Z. Chi ◽  
Y. Song
Keyword(s):  
Spectrophotometric Determination ◽  
Maximum Absorption ◽  
Optimum Conditions ◽  
Good Linear ◽  
Linear Correlations ◽  
Decolorization Of Dyes

Dyes can be decolorized by the activation of peroxymonosulfate (PMS) in the presence of cobalt, and four good linear correlations between the depletion of dyes at their maximum absorption wavelengths and the concentration of PMS are demonstrated under the optimum conditions.

Theoretical calculation of the maximum absorption wavelength for Cyanidin molecules with several methodologies

2015 ◽  
Vol 1067 ◽  
pp. 129-134 ◽  
Author(s):  
Nora-Aydee Sanchez-Bojorge ◽  
Luz-Maria Rodriguez-Valdez ◽  
Daniel Glossman-Mitnik ◽  
Norma Flores-Holguin
Keyword(s):  
Theoretical Calculation ◽  
Maximum Absorption ◽  
Maximum Absorption Wavelength ◽  
Absorption Wavelength

The Interaction between Reactive Dye and Octyl Trimethyl Ammonium Chloride

2013 ◽  
Vol 781-784 ◽  
pp. 2712-2715
Author(s):  
Yu Kun Si ◽  
Jian Feng Zhou ◽  
Li Yuan Qu ◽  
Ling Zhong ◽  
Feng Xiu Zhang ◽  
...  
Keyword(s):  
Particle Size ◽  
Ammonium Chloride ◽  
Reactive Dyes ◽  
Reactive Dye ◽  
Maximum Absorption ◽  
Trimethyl Ammonium Chloride ◽  
Dye Molecules ◽  
Maximum Absorption Wavelength ◽  
Dye Molecule ◽  
Absorption Wavelength

Octyl trimethyl ammonium chloride (OTMAC) is a very efficient accelerant for reactive dyes on dyeing silk. In order to understand the accelerating mechanism, the interaction between dye molecules and OTMAC molecule was studied in this paper. The results showed that the DTMAC made the dye molecules assembled and the particle size of dye assemblages could reach to more than 500nm. The assembling of dye molecules leads to increase of the maximum absorption wavelength of dye. The higher the temperature is, the weaker the interaction between dye molecule and accelerant.

Based on the Protection of Water Pack Polysaccharide Processing Technology and its Optimization

2014 ◽  
Vol 1056 ◽  
pp. 107-113
Author(s):  
Yun Long Zhu ◽  
Qian Qian Wang ◽  
Yang Yuan ◽  
Jing Jing Zhu
Keyword(s):  
Heating Temperature ◽  
Retention Rate ◽  
Heating Time ◽  
Processing Method ◽  
Slice Thickness ◽  
Optimal Process ◽  
Frying Time ◽  
Heating Treatment ◽  
Baked Products

Purpose: For health water pack polysaccharide easy loss occurred during processing, establish a high retention rate of the processing method. Method: Chooseing slice thickness, heating time and temperature as the parameter, the water pack for steaming, boiled, Fried, baked oil heating treatment, determination of the water pack polysaccharide content, it is concluded that optimal process parameters, the retention rate of statistics. Results: The best conditions for water pack all kinds of processing method is: (1) steamed products: slice thickness of 1.6 cm, 106 °C steamed 10 mins; (2) boiled products: slice thickness of 1.2 cm, 90 °C cooked for 10 mins; (3) baked products: the slice thickness of 0.2 cm, 160 °C baking 14 mins; (4) Fried products: the slice thickness of 0.2 cm, and 150 °C the frying time of 5.5 mins. Processing products in water pack polysaccharide retention rate is as follows: Steaming > Boiled > Fried > Baking. Conclusion: steamed processing for water pack polysaccharide retention rate is high, is the water pack of preferred processing method; Boiled, grilled, Fried method should choose low heating temperature.

scholarly journals Determination of Isoniazid by Fe(II)-2,2’-Bipyridine Spectrophotometry

2021 ◽  
Vol 290 ◽  
pp. 01028
Author(s):  
Changqing Tu ◽  
Xinrong Wen
Keyword(s):  
Linear Regression ◽  
Linear Relationship ◽  
Correlation Coefficient ◽  
Linear Correlation ◽  
Mass Concentration ◽  
Linear Regression Equation ◽  
Optimum Conditions ◽  
Acidic Media ◽  
Maximum Absorption Wavelength

In acidic media, Fe(Ш) could be reduced to Fe(Ⅱ) by isoniazid, Fe(Ⅱ) reacts with 2,2'-bipyridine to form an orange complex with a maximum absorption wavelength of 522 nm. According to this principle, the content of isoniazid can be measured indirectly by measuring the amount of Fe(Ⅱ). A new method for the determination of isoniazid by Fe(Ⅱ)-2,2'-bipyridine spectrophotometry has been established. At the optimum conditions, the linear relationship is good between the mass concentration of isoniazid and absorbance of Fe(Ⅱ)-2,2'-bipyridine complex in the range of 0.0004000-0.002800 mg/mL. The linear regression equation is A=0.0251+138.04C(mg/mL), and the linear correlation coefficient is 0.9995. This method is used to determine the content of isoniazid in isoniazid tablets, and the results are similar to those obtained by pharmacopoeia method.

2-chloromethyl-5-aryl-1,3,4-oxadiazole Synthesis and Properties of Compounds

2012 ◽  
Vol 554-556 ◽  
pp. 768-771
Author(s):  
Xiong Lu Zhang ◽  
Qiu Yan Qin ◽  
Yi Ping Qian ◽  
Hong Xiao
Keyword(s):  
Thermal Stability ◽  
Fluorescence Spectroscopy ◽  
Oxidation Resistance ◽  
Fluorescence Emission ◽  
Maximum Absorption ◽  
Blue Fluorescence ◽  
Excellent Thermal Stability ◽  
Ft Ir ◽  
Maximum Absorption Wavelength ◽  
Absorption Wavelength

1,3,4-oxadiazole(OXD) and its derivatives have excellent thermal stability and oxidation resistance and strong blue fluorescence emission[1].Six novel compounds have been designed and and synthesized. And their structures were confirmed by 1HNMR,FT-IR MS, UV-vis absorption results showed that the maximum absorption wavelength appeared at 304 nm，and fluorescence spectroscopy results showed that they emit strong purple fluorescence in DMF solution.

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