Sodium hydroxide treatments

There is also evidence that at least some of the phenolic aldehydes and dehydrodiferulic acid (Figure 1) are linked covalently to cell wall polysaccharides. When ryegrass cell walls were treated with cellulase, the aldehydes and the acid were released as water-soluble carbohydrate-aromatic compounds from which the aromatics were released by cold sodium hydroxide treatment (6,7). This suggests that these compounds are either ether-linked or, in the case of the acid, ester-linked to the polysaccharides. 

The chemical treatment used depends upon the composition of the mineral. The sodium hydroxide treatment of monazite. Figure 8, is preferably used since it has the advantage of removing phosphates more readily than the sulfuric acid procedure. 

Gluconates and glucoheptonates are essential components of many alkaline rust removers and cleaners, paint strippers, and etchants. They frequently cause complexation of dissolved heavy metals such as copper, nickel, and zinc. Conventional sodium hydroxide treatment does not result in sufficient precipitation of these complexed metals to meet EPA standards. In tests performed by Srinivasan (1983), the use of lime or calcium hydroxide proved far better. In particular, lime treatment resulted in more metal removal, better flocculation and faster sludge settling, and could also be used in conjunction with sodium hydroxide treatment. 

A number of so-called 2,4-dihydroxyquinolines, after the introduction of a 3-hydroxyimino,106 3-nitroso,107 108 3-hydroxv-3-amino,109 or more frequently 3,3-dihalo groups,110-114 give isatins with sulfuric acid or sodium hydroxide. Treatment with sodium hydroxide of 3,3-... 

Pyrrolopyridines are quaternized at the pyridine nitrogen by methyl iodide (often at room temperature). Sodium hydroxide treatment of the methiodide of pyrrolo[2,3-6]pyridine gives a stable free base which reacts with a second molecule of methyl iodide, this time at the pyrrole nitrogen (Scheme 4). The resonance stabilization of the free base is shown by its stability towards boiling 20% sodium hydroxide, which rapidly hydrolyzes l-methyl-2-pyridoneimine (55JA6554). The same procedure with S-carboline leads to the 1,5-dimethyl quaternary salt (19) which on pyrolysis yields the 5-methyl derivative (20 Scheme 5) (60CJC2152). 

A compound formulated as 5-methyl-1,4-dihydro-1,2,4-triazin-3(2//)-one (696) was obtained by sodium hydroxide treatment of compound (697). Reacting (697) with thallium ethoxide led to the isolation of diethyl 5-methyl-3-oxo-l,2,3,4-tetrahydro-l,2,4-triazine-1,6-dicarboxylate (698) (70JOC3792). Since compound (697) is formed by reaction of aminocrotonic ester with diethyl azodicarboxylate, these reactions can also be treated as [3 + 3] atom component preparations. 

Proline catalyses an aldol-type addition of acyl cyanides (RCOCN) to acetone to give ft-kclocyanohydri ns (42) sodium hydroxide treatment gives the corresponding 1,3-diketone (43), by elimination of HCN.153... 

Methylpyrazine reacts with formaldehyde and dimethylamine to give the expected product (40) of Mannich reaction. This is converted in 63% overall yield to vinylpyrazine (41) by quaternization with methyl iodide followed by sodium hydroxide treatment.196... 

As with dilute sodium hydroxide, treatment with concentrated formic acid results in slow hydrolytic cleavage of peptide bonds. Ayers and his... 

The stability of 1,1-enediamines and their amidinium salts merits comment. Secondary and tertiary 1,1-enediamines substituted by two )S-electron-withdrawing substituents such as 104 are quite stable, being unaffected by refluxing with aqueous sodium hydroxide. Treatment of their salts with base regenerates the parent enediamines. On the other hand, 103 or its salt 106, undergoes hydrolysis to give iV-pentamethylene-TV -phenylmalonamide. Simple 1,1-enediamines or their salts are very sensitive to hydrolysis, leading to amides... 

Zhao, X., Liu, X., Ding, C., and Chu, P.K. (2006) In vitro bioactivity of plasma-sprayed Ti02 coating after sodium hydroxide treatment. Surf. Coat. Technol., 200 (16/18), 5487 -5492. 

Kerr (d) has shown that during the thermal decomposition of ammonium Y zeolite at 500 °C there is a loss of aluminum if a deep bed geometry is employed. In the particular material that Kerr studied, sodium hydroxide treatment of the deep bed sample led to the increase... 

D. M. Updegraff (Univ. of Denver) Do you know of any ruminant feeding experiment in which instead of the sodium hydroxide treatment of sawdust or wood products, waste paper was used, since this has approximately the same composition as the other products ... 

Two chiral manganese(III) salen catalysts, bearing different chiral diamine bridges (Figure 8.5) [74] were anchored by direct axial coordination of the metal center onto the phenolate groups created by sodium hydroxide treatment of an air-oxidized AC, as confirmed by XPS and TPD the air activation of these materials introduced mainly phenol and carbonyl-quinone groups that upon reflux with a sodium hydroxide solution were converted into phenolates. This method was also applied to anchoring of the Jacobsen catalyst onto air-oxidized CXs... 

Milk is defatted by centrifugation, animal tissues by heating and sedimentation. Saponification is no longer accomplished by sodium hydroxide treatment, but by active earth-catalyzed hydrolysis close to neutral pH values. 

Pyridine A -oxides protonate and are alkylated at oxygen stable salts can be isolated in some cases. Hot aqueous sodium hydroxide treatment of alkoxypyridinium salts produces aldehydes corresponding to the alkoxy substituent. ... 

Zein, which is the major protein in corn, was chosen because it contains no lysine. This precluded the formation of LAL during alkali treatment. Therefore, any changes in digestibility or uptake could be attributed to racemization effects alone. Additionally, we were interested in comparing the effects of sodium hydroxide treatment with the effects of calcium hydroxide treatment because lime is used in the preparation of corn meal for use in tortillas. If the traditional lime treatment of com meal is unnecessarily harsh, it could have important nutritional consequences because a large segment of the Mexican population obtains much of their dietary protein in the form of tortillas (22). 

The results from the everted sac experiments were that both calcium hydroxide and sodium hydroxide treatment significantly decrease in vitro digestibility, but that only sodium hydroxide treatment affects uptake of the zein hydrolysates. Because of the minimal effects of calcium hydroxide treatment on accumulation, we decided to reexamine the uptake phenomenon using an... 

A summary of the results from the perfused intestine experiment is shown in Figure 8. The results are expressed as the mean uptake of all the measured amino acids for the three zein hydrolysates. The results from this series clearly show that uptake has been reduced by both soda- and lime-treatments of zein, which is also consistent with the results of the pronase study which show that both calcium hydroxide and sodium hydroxide treatments decrease digestibility. However, it is not clear why the results for Ca(0H)2 treated zein are different for the everted sac and perfusion experiments, hut this may be related to the better viability of the in vivo perfusion technique. 

Microscopic examination of the substrate particles showed that cells of the substrate tissue were loosely held together and tended to separate easily when pressed. It Indicated that sodium hydroxide treatment solubilized lignin and weakened the bonds of adjacent cells. Figure 5 shows broken ends of cells on the sides... 

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