The influence of pH on the reaction between tartaric acid and metaperiodic acid

1968 ◽  
Vol 21 (6) ◽  
pp. 1531 ◽  
Author(s):  
PS Verma ◽  
KC Grover
Keyword(s):  
Formic Acid ◽  
Tartaric Acid ◽  
Coordination Compound ◽  
Phosphate Buffer ◽  
Periodic Acid ◽  
Glyoxylic Acid ◽  
Second Order ◽  
Influence Of Ph

Tartaric acid in phosphate buffer (pH 6.6) at 30� consumed 2,003 � 0.001 molar proportions of periodic acid in 2.5 hr. The reaction has been shown to be of second order. It is suggested that the oxidation proceeds through the disproportionation of a coordination compound intermediate involving the bitartrate and IO4 or H4IO4 ions, followed by the subsequent slow oxidation of glyoxylic acid to give formic acid.

A CHEMICAL PROCEDURE FOR DETERMINATION OF THE C14-DISTRIBUTION IN LABELLED XYLOSE

1955 ◽  
Vol 33 (1) ◽  
pp. 368-373 ◽  
Author(s):  
Stewart A. Brown
Keyword(s):  
Carbon Dioxide ◽  
Formic Acid ◽  
Glycolic Acid ◽  
Periodic Acid ◽  
Glyoxylic Acid ◽  
Lead Tetraacetate ◽  
Carbon 14 ◽  
Chemical Procedure ◽  
Purified Salt

A series of reactions reported previously for the degradation of glucose has been modified and extended to permit the determination of carbon-14 in each of the five carbons of a single 2 mM. xylose sample. Methyl xylopyranoside was oxidized with periodic acid giving C-3 as formic acid, and a dialdehyde which was converted to strontium methoxy-diglycolate. The purified salt was hydrolyzed to glyoxylic and glycolic acids. The glyoxylic acid was isolated as the 2, 4-dinitrophenylhydrazone (C-1 + C-2) which was decarboxylated to give carbon dioxide from C-2. The glycolic acid was oxidized by lead tetraacetate to give C-4 as carbon dioxide and C-5 as formaldehyde. The activity in C-1 was determined by difference. The method was applied to xylose-1-C14, xylose-5-C14, and a biologically synthesized xylose sample with satisfactory results. This degradation procedure is theoretically applicable to other aldopentoses and aldotetroses.

A CHEMICAL PROCEDURE FOR DETERMINATION OF THE C14-DISTRIBUTION IN LABELLED XYLOSE

1955 ◽  
Vol 33 (3) ◽  
pp. 368-373 ◽  
Author(s):  
Stewart A. Brown
Keyword(s):  
Carbon Dioxide ◽  
Formic Acid ◽  
Glycolic Acid ◽  
Periodic Acid ◽  
Glyoxylic Acid ◽  
Lead Tetraacetate ◽  
Carbon 14 ◽  
Chemical Procedure ◽  
Purified Salt

A series of reactions reported previously for the degradation of glucose has been modified and extended to permit the determination of carbon-14 in each of the five carbons of a single 2 mM. xylose sample. Methyl xylopyranoside was oxidized with periodic acid giving C-3 as formic acid, and a dialdehyde which was converted to strontium methoxy-diglycolate. The purified salt was hydrolyzed to glyoxylic and glycolic acids. The glyoxylic acid was isolated as the 2, 4-dinitrophenylhydrazone (C-1 + C-2) which was decarboxylated to give carbon dioxide from C-2. The glycolic acid was oxidized by lead tetraacetate to give C-4 as carbon dioxide and C-5 as formaldehyde. The activity in C-1 was determined by difference. The method was applied to xylose-1-C14, xylose-5-C14, and a biologically synthesized xylose sample with satisfactory results. This degradation procedure is theoretically applicable to other aldopentoses and aldotetroses.

A CHEMICAL PROCEDURE FOR DETERMINATION OF THE C14-DISTRIBUTION IN LABELED GLUCOSE

1955 ◽  
Vol 33 (1) ◽  
pp. 62-68 ◽  
Author(s):  
B. Boothroyd ◽  
Stewart A. Brown ◽  
J. A. Thorn ◽  
A. C. Neish
Keyword(s):  
Carbon Dioxide ◽  
Formic Acid ◽  
Periodic Acid ◽  
Glyoxylic Acid ◽  
Glyceric Acid ◽  
Diglycolic Acid ◽  
Glucose Molecule ◽  
Strontium Salt ◽  
Chemical Procedure

A procedure based on the work of Jackson and Hudson was developed for the degradation of methyl-α-D-glucopyranoside formed from 2 millimoles of glucose. Oxidation of the glucoside with periodic acid gave C-3 as formic acid and a dialdehyde which was converted to the strontium salt of D′-methoxy-D-hydroxymethyl diglycolic acid. The purified salt was hydrolyzed to glyoxylic and glyceric acids. The glyoxylic acid was isolated as the 2,4-dinitrophenylhydrazone (C-1 + C-2); this was decarboxylated by heat to give carbon dioxide from C-2. The glyceric acid was oxidized by periodate to give C-4 as carbon dioxide, C-5 as formic acid, and C-6 as formaldehyde. This degradation permitted the determination of C14 in each position of the glucose molecule, the activity in C-1 being determined by difference. The method was applied to glucose-1-C14 and a sample of glucose labeled in all positions with satisfactory results.

A CHEMICAL PROCEDURE FOR DETERMINATION OF THE C14-DISTRIBUTION IN LABELED GLUCOSE

1955 ◽  
Vol 33 (1) ◽  
pp. 62-68 ◽  
Author(s):  
B. Boothroyd ◽  
Stewart A. Brown ◽  
J. A. Thorn ◽  
A. C. Neish
Keyword(s):  
Carbon Dioxide ◽  
Formic Acid ◽  
Periodic Acid ◽  
Glyoxylic Acid ◽  
Glyceric Acid ◽  
Diglycolic Acid ◽  
Glucose Molecule ◽  
Strontium Salt ◽  
Chemical Procedure

A procedure based on the work of Jackson and Hudson was developed for the degradation of methyl-α-D-glucopyranoside formed from 2 millimoles of glucose. Oxidation of the glucoside with periodic acid gave C-3 as formic acid and a dialdehyde which was converted to the strontium salt of D′-methoxy-D-hydroxymethyl diglycolic acid. The purified salt was hydrolyzed to glyoxylic and glyceric acids. The glyoxylic acid was isolated as the 2,4-dinitrophenylhydrazone (C-1 + C-2); this was decarboxylated by heat to give carbon dioxide from C-2. The glyceric acid was oxidized by periodate to give C-4 as carbon dioxide, C-5 as formic acid, and C-6 as formaldehyde. This degradation permitted the determination of C14 in each position of the glucose molecule, the activity in C-1 being determined by difference. The method was applied to glucose-1-C14 and a sample of glucose labeled in all positions with satisfactory results.

scholarly journals Influence of pH and Matric Potential on Germination of Cephalosporium gramineum Conidia

Plant Disease ◽  
1998 ◽  
Vol 82 (9) ◽  
pp. 975-978 ◽  
Author(s):  
Cynthia A. Blank ◽  
Timothy D. Murray
Keyword(s):  
Soil Moisture ◽  
Soil Ph ◽  
Significant Influence ◽  
Phosphate Buffer ◽  
Mineral Salts ◽  
Matric Potential ◽  
High Soil Moisture ◽  
Soil Fungistasis ◽  
Cephalosporium Gramineum ◽  
Influence Of Ph

Germination of Cephalosporium gramineum conidia in soil was up to twofold greater at -0.064 MPa than at -0.037 and -0.007 MPa when incubated at 5°C for 2 days. Soil pH from 4.7 to 7.5 did not have a significant influence on germination of conidia and the interaction between soil pH and matric potential on germination was not significant. Soil fungistasis, which was previously observed for conidia of C. gramineum, was not observed in these studies. Germination of conidia on mineral salts agar containing phosphate buffer was significantly less at pH 4.5 than at 5.5, 6.5, or 7.5 at 5°C in one of two experiments; however, pH had no influence on germination at 10 or 20°C in two experiments. Although Cephalosporium stripe is more severe under conditions of high soil moisture and low soil pH, increased germination of conidia in response to these factors does not explain the observed increase in disease.

OXIDATION OF WHEAT STARCH WITH ALKALINE HYPOCHLORITE

1961 ◽  
Vol 39 (1) ◽  
pp. 61-72 ◽  
Author(s):  
A. A. Eisenbraun ◽  
C. B. Purves
Keyword(s):  
Oxalic Acid ◽  
Tartaric Acid ◽  
Glucuronic Acid ◽  
Carbonic Acid ◽  
Glyoxylic Acid ◽  
Wheat Starch ◽  
Calcium Hypochlorite ◽  
First Order ◽  
Tartronic Acid

The starch was oxidized with 5.5 base molar equivalents of 0.43 M calcium hypochlorite kept near pH 12 and 20°. The rate of oxidation was consistent with the occurrence of two first-order reactions differing in rate by a factor of 10, the more rapid of which consumed about 4 moles of hypochlorite for each C6H10O5 unit actually oxidized. Oxalic acid (0.2 mole) and perhaps carbonic acid [Formula: see text] were formed directly, but it was necessary to hydrolyze the product in order to liberate D-glucose (0.4 mole), glyoxylic acid (0.03 mole), D-erythronic acid (0.11 mole), mesotartaric acid (0.02 mole), D-tartaric acid (0.02 mole), L-tartaric acid (0.01 mole), D-glucuronic acid (0.004 mole), and probably tartronic acid [Formula: see text].

Dissolution of wood in α-keto acid and aldehydic carboxylic acids and fractionation at room temperature

2014 ◽  
Vol 16 (7) ◽  
pp. 3569-3579 ◽  
Author(s):  
Yuri Nishiwaki-Akine ◽  
Takashi Watanabe
Keyword(s):  
Formic Acid ◽  
Carboxylic Acids ◽  
Pyruvic Acid ◽  
Ball Mill ◽  
Room Temperature ◽  
Glyoxylic Acid ◽  
Keto Acid

Wood pulverised using a ball mill was dissolved in an α-keto acid, pyruvic acid, and two aldehydic carboxylic acids, namely glyoxylic acid and formic acid, at room temperature.

The homogeneous decomposition reactions of gaseous formic acid

1960 ◽  
Vol 255 (1283) ◽  
pp. 444-455 ◽  
Keyword(s):  
Formic Acid ◽  
Kinetic Parameters ◽  
Rate Constant ◽  
Ion Pairs ◽  
Order Rate Constant ◽  
Second Order ◽  
Unimolecular Decomposition ◽  
Order Component ◽  
First Order ◽  
Homogeneous Decomposition

By use of reaction vessels with specially treated surfaces the homogeneous decomposition of formic acid has been studied kinetically in the range 436 to 532°C. Neither of the two simultaneous reactions ( a ) HCOOH = CO 2 + H 2 , ( b ) HCOOH = CO + H 2 O, is retarded by the usual inhibitors of chain processes. Each appears to be molecular. Reaction ( a ) is of the first order in the range 3 to 650 mm, the first-order rate constant being given by k CO 2 = 10 4⋅8 exp (–30600/ RT )s -1 . It is suggested tentatively that the abnormal kinetic parameters might be explained by regarding the reaction as a decarboxylation of (H + ) (HCOO¯) ion pairs present in minute concentration. Reaction ( b ) shows a pressure dependence most simply explained by a superposition of a predominant second-order component with a small first-order component. The most satisfactory interpretation of the second-order reaction is that it represents the unimolecular decomposition of dimer molecules, known to be present in formic-acid vapour. On this basis the rate constant is given by k CO dimer = 10 13⋅58 exp (–42600/ RT )s -1 , the kinetic parameters thus being in the normal range. The various alternative interpretations are discussed.

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