Plastics. Melamine-formaldehyde mouldings. Determination of extractable formaldehyde

1978 ◽  
Keyword(s):  
Melamine Formaldehyde

IR spectroscopy: Suitable method for determination of curing degree and crosslinking type in melamine–formaldehyde resins

2019 ◽  
Vol 136 (25) ◽  
pp. 47691 ◽  
Author(s):  
Stephanie Weiss ◽  
Katharina Urdl ◽  
Hermann A. Mayer ◽  
Edith M. Zikulnig‐Rusch ◽  
Andreas Kandelbauer
Keyword(s):  
Ir Spectroscopy ◽  
Suitable Method ◽  
Melamine Formaldehyde

Liquid Chromatographic Determination of Melamine in Beverages

1987 ◽  
Vol 70 (3) ◽  
pp. 457-460 ◽  
Author(s):  
Hajimu Ishiwata ◽  
Takiko Inoue ◽  
Takeshi Yamazaki ◽  
Kunitoshi Yoshihira
Keyword(s):  
Exchange Resin ◽  
Anion Exchange Resin ◽  
Chromatographic Determination ◽  
Formaldehyde Resin ◽  
Melamine Formaldehyde ◽  
Quantitation Limit ◽  
Liquid Chromatographic Method ◽  
Liquid Chromatographic Determination ◽  
Liquid Chromatographic

Abstract A liquid chromatographic method is described for the determination of melamine in beverages. Melamine is separated by column chromatography using cation and anion exchange resin and determined by ion-pair liquid chromatography using an ODS column and a mixture of acetonitrile and 0.05M phosphate buffer (pH 3.0) containing 0.005M sodium 1-laurylsulfate (1 + 4, v/v) as mobile phase. Recoveries of melamine ranged between 90.3 ± 7.8 and 102.1 ± 5.6% at levels of 0.6 to 2.4 ppm in 4 kinds of beverages. The quantitation limit was 2.5 μg melamine in 50 mL beverage. The method was applied to the migration test of melamine from melamine-formaldehyde resin products to the beverages.

scholarly journals Determination of the pH Gradient in Hair Follicles of Human Volunteers Using pH-Sensitive Melamine Formaldehyde-Pyranine Nile Blue Microparticles

Sensors ◽  
2020 ◽  
Vol 20 (18) ◽  
pp. 5243 ◽  
Author(s):  
Dennis Kaden ◽  
Lars Dähne ◽  
Fanny Knorr ◽  
Heike Richter ◽  
Jürgen Lademann ◽  
...  
Keyword(s):  
Hair Follicle ◽  
Laser Scanning ◽  
Nile Blue ◽  
Hair Shaft ◽  
Hair Follicles ◽  
Laser Scanning Microscopy ◽  
Confocal Laser ◽  
Melamine Formaldehyde

Nanoparticles can be applied to the hair follicles, which can serve as reservoirs for triggered drug release. A valid measurement method for the determination of the pH within the hair follicle in vivo has not been shown yet. Here, melamine formaldehyde particles up to 9 µm in size were applied on 40 freshly plucked scalp hairs of eight individuals to determine the pH along the hair shaft down to the root area of the hair. For fluorescent pH indicators, pyranine and Nile blue were incorporated into the particles. Measurements were conducted using confocal laser scanning microscopy. A pH decay gradient could be found from the hair sheath towards the external hair shaft (p = 0.012) with pH values at the hair sheath of 6.63 ± 0.09, at the hair sheath end at 6.33 ± 0.11, and at the external hair shaft at 6.17 ± 0.09 (mean ± SE). The pH difference between the hair sheath end and the external hair shaft was found to be significant (p = 0.036). The results might be comparable with the pH within the hair follicle in vivo indicating a pH increase towards the hair root.

Convenient determination of methoxy groups of methylated melamine-formaldehyde resins by IR spectroscopy

1987 ◽  
Vol 34 (7) ◽  
pp. 2601-2607 ◽  
Author(s):  
Noriyuki Miyauchi ◽  
Toshio Takeshita ◽  
Mitsuru Akashi ◽  
Riyoko Machida
Keyword(s):  
Ir Spectroscopy ◽  
Melamine Formaldehyde ◽  
Methoxy Groups
Sign in / Sign up

Export Citation Format

Share Document