What's the difference between formaldehyde and melamine?
Formaldehyde
Definition:
(n.) A colorless, volatile liquid, H2CO, resembling acetic or ethyl aldehyde, and chemically intermediate between methyl alcohol and formic acid.
Example Sentences:
(1) At the light-microscopic level, adrenergic fibres were identified due to their formaldehyde-induced fluorescence.
(2) Alcohol oxidase and catalase, which catalyse the oxidation of methanol to formaldehyde in Candida boidinii, could be localized within the peroxisomes.
(3) These results suggest that formaldehyde has tumor-promoting activity in carcinogenesis in the glandular stomach.
(4) Colitis was induced in the distal colon by rectal infusion of formaldehyde solution, followed by an intravenous bolus of soluble immune complexes.
(5) The variables tested were: formaldehyde concentration, pH, time, and temperature.
(6) In the scope of our research about the antimicrobial activity of aldehyde-amin-condensates a number of partly new unsymmetrically substituted animals was synthesized by reaction of formaldehyde with different secondary amines.
(7) The fluorescence anisotropy changes observed in A-1 (H1N1) influenza and Sendai parainfluenza viruses in aqueous suspensions when formaldehyde (0.1 to 1.0 p.c.)
(8) Similar results were obtained when hybrid-selected RNA, which had been labeled for 3 h with [3H]uridine, was analyzed on formaldehyde-agarose gels, suggesting that the observed differences were due to splicing rather than RNA stability.
(9) The relative toxicities of formaldehyde and glutaraldehyde to the rat nasal epithelium were determined following intra-nasal instillation of aqueous solutions of these compounds into one nostril of male Fischer 344 (F-344) rats.
(10) When tissue metabolism was irreversibly inhibited by exposure to formaldehyde, hydrogen ion concentration and pCO2 were significantly decreased in the mucosal side of the chamber compared with the viable gall bladder.
(11) Whereas the diagnosis unequivocally could be established by semithin sections the diagnosis was doubtful using material fixed with Bouin's solution and overlooked when the material was fixed with 4% formaldehyde solution.
(12) Key intermediate of the synthesis was 2-formyl-estradiol (2) which was prepared in quantitative yield through reaction of the phenoxymagnesium bromide of estradiol with formaldehyde in the presence of HMPA.
(13) In 139 persons occupationally exposed to compounds of chromium, formaldehyde and p-phenylenediamine lymphocytic transformation test (ltt) was performed to detect a delayed-type hypersensitivity.
(14) Microwave fixation in dilute aldehyde solution has been reported to be superior to fixation in formaldehyde for the preservation of antigens.
(15) Isolated nuclei from green leaf tissue of tomato plants infected with potato spindle tuber viroid (PSTVd) were bound to microscope slides, fixed with formaldehyde and hybridized with biotinylated transcripts of cloned PSTVd cDNA.
(16) Adverse reactions to phenol-formaldehyde resins include depigmentation, irritant dermatitis, chemical burns and allergic contact dermatitis.
(17) The merits of formaldehyde, formaldehyde-glutaraldehyde combinations, and glutaraldehyde in phosphate buffers have been compared as fixatives that will give easy and satisfactory preservation of tissues for routine automated histologic processing and yet keep them suitable for electron microscopical studies after prolonged storage at room temperature.
(18) The optimum hybridization procedure was found to be incubation of serum samples with salt, NaOH, formaldehyde and detergent, followed by spot application of the samples.
(19) A mixture of 4% formaldehyde and 0.5% glutaraldehyde gave the best combination of ultrastructural preservation and retention of enzyme activity.
(20) In second group after thoracotomy the lungs were stabilized with gelatin-resorcin-formaldehyde glue.
Melamine
Definition:
(n.) A strong nitrogenous base, C3H6N6, produced from several cyanogen compounds, and obtained as a white crystalline substance, -- formerly supposed to be produced by the decomposition of melam. Called also cyanuramide.
Example Sentences:
(1) An air sampling and liquid chromatographic separation method for melamine is described.
(2) The melamine forms disordered crystals of orthorhombic symmetry with a = 11.957(3), b = 17.267(3), c = 5.769(3)A.
(3) Sample materials studied were melamine resin, polyethylene, polypropylene, polystyrene, and polyvinyl chloride.
(4) A new cell culture technique is described which is based on the observation that foils cast from the melamine resin hexamethylol-melamine-ether are suitable for the cultivation of beating heart muscle cells and fibroblasts of the rat.
(5) Treatment of Vicia faba main root meristems with methyl iodide (MeI) 2 h before challenge treatment with triethylene melamine (TEM) significantly reduced the yield of metaphases with chromatid aberrations, i.e., resulted in clastogenic adaptation.
(6) When Saccharomyces cerevisia MP1 was treated with bile acids alone or in combination with triethylene melamine (TEM), cholic acid was found to be comutagenic and antirecombinogenic while lithocholic acid had the opposite effect.
(7) The method of tissue embedding in melamine resin was applied to rat skeletal muscle.
(8) Moreover, the domains observed in hydrosoluble resin-embedded tissue shrink differently according to the proportion of water removed by melamine; this can provide interesting information on the initial equilibrium between water, ion sand macromolecules.
(9) It is based on the polycondensation of amphiphilic and, thus, tensioactive precondensates on a melamine-formaldehyde base on the surface of suspended particles during spray drying.
(10) Melamine resins are derived from the heterocyclic compound triaminotriazine, C3H6N6.
(11) The relationship between the concentrations of formaldehyde and melamine released into 4% acetic acid from dishes and bowls made of melamine-formaldehyde resin was determined.
(12) The correlation between the concentrations of formaldehyde and melamine released at 95 degrees C was y=0.4858x-0.2728 (r=0.8860), where y is melamine concentration (ppm), x is formaldehyde concentration (ppm) and r is the correlation coefficient.
(13) The molecular ratio of the migration amount of formaldehyde to melamine decreased according to the formula Y = 9.15X-0.813 over seven repetitions of the test, and was maintained at about 1.6 between the 10th and 20th repetitions.
(14) Hexamethylmelamine (HXM) is one of the substituted melamines derived from cyanuric chloride [1].
(15) Because they can be sectioned extremely thinly, melamine resins are particularly suitable for dark-field and electron spectroscopic imaging of unstained molecular suspensions providing in this way an unusually clear reproduction of ultrastructural detail such as the helical structure of isolated unstained double-strand DNA molecules (Frösch et al., 1987b).
(16) In melamine-embedded muscles the actin and myosin filaments appear larger in diameter and subunits can be recognized in cross-sectioned myosin filaments.
(17) Electron micrographs of muscles embedded in melamine differ from those embedded in the conventional epoxy resin.
(18) The potential of Nanoplast melamine resin embedding for the study of mammalian lung parenchyma was examined by means of electron spectroscopic imaging (ESI) and electron energy-loss spectroscopy (EELS).
(19) The potential advantages of Trimelamol over previously tested melamines are discussed.
(20) We have used two-dimensional gel electrophoresis (2DE) coupled with computer-assisted data analysis to analyze liver-protein expression in mice known to be heterozygous carriers of recessive lethal mutations induced in In(1)1Rk or In(7)13Rk inversion stocks by exposure to either triethylene melamine or ionizing radiation.