Kinetics of the chromium(VI)-arsenic(III)reaction. II. Dihydrogen phosphate-hydrogen phosphate buffer solutions

1970 ◽  
Vol 9 (4) ◽  
pp. 847-850 ◽  
Author(s):  
John G. Mason ◽  
Albert D. Kowalak ◽  
R. Michael Tuggle
Keyword(s):  
Phosphate Buffer ◽  
Dihydrogen Phosphate ◽  
Hydrogen Phosphate ◽  
Buffer Solutions ◽  
Chromium Vi ◽  
Kinetics Of

Kinetics of Electrochemical Reduction of Carbon Dioxide on a Gold Electrode in Phosphate Buffer Solutions

1995 ◽  
Vol 68 (7) ◽  
pp. 1889-1895 ◽  
Author(s):  
Hidetomo Noda ◽  
Shoichiro Ikeda ◽  
Akio Yamamoto ◽  
Hisahiko Einaga ◽  
Kaname Ito
Keyword(s):  
Carbon Dioxide ◽  
Electrochemical Reduction ◽  
Phosphate Buffer ◽  
Gold Electrode ◽  
Buffer Solutions ◽  
Kinetics Of

Viral inactivation by potassium ferrate

1995 ◽  
Vol 31 (5-6) ◽  
pp. 165-168 ◽  
Author(s):  
Futaba Kazama
Keyword(s):  
Phosphate Buffer ◽  
Potassium Ferrate ◽  
Sodium Thiosulphate ◽  
Viral Inactivation ◽  
Complete Decomposition ◽  
Kinetics Of ◽  
Oxidative Intermediate

The kinetics of inactivation by potassium ferrate were studied using a bacteriophage, F-specific RNA-coliphage Qβ as a viral model. The inactivation appeared to be expressed by Hom's model in phosphate buffer at pH 6, 7, and 8. The rate of inactivation depended on pH; the lower pH, the faster inactivation observed. To consider the mechanism by which ferrate caused inactivation, the efficiency of inactivation was checked after ferrate decomposition in buffer. Effective inactivation following Hom's model was also observed after the complete decomposition of ferrate ion; however, the efficiency of that inactivation disappeared by the addition of sodium thiosulphate, suggesting that rather long-lived oxidative intermediate was generated by the decomposition of ferrate ion. The intermediate might take part in the inactivation.

scholarly journals OBSERVATIONS IMPLICATING AN EXTRACELLULAR ENZYMIC MECHANISM OF CONTROL OF BONE MORPHOGENESIS

1974 ◽  
Vol 22 (2) ◽  
pp. 88-103 ◽  
Author(s):  
MARSHALL R. URIST ◽  
HISASHI IWATA ◽  
STUART D. BOYD ◽  
PETER L. CECCOTTI ◽  
MARLYS OKADA ◽  
...  
Keyword(s):  
Chemical Reactions ◽  
Phosphate Buffer ◽  
Bone Matrix ◽  
Chemical Extraction ◽  
Ammonium Bromide ◽  
Property A ◽  
Noncollagenous Proteins ◽  
Buffer Solutions ◽  
Sequential Chemical Extraction ◽  
Chloroform Methanol

Data on physicochemical conditions leading to loss of the bone morphogenetic property of bone matrix in neutral buffer solutions support the concept of an enzymic control mechanism better than a chemical blocking reaction or denaturation. The loss is associated with release of 35S-labeled constituents and not prevented by ε-amino caproic acid, an inhibitor of cathepsins. The loss is also associated with release of 35S-cysteine-labeled protein; about 60% of the yield is sustained by the addition of only 3 mmoles/liter of iodoacetic acid. A latent period of about 12 hr, decreased by extraction of bone matrix with CaCl2, is characterized by release of protein polysaccharide and other noncollagenous proteins. Release of sialic acid from the bone matrix by neuraminidase at pH 7.4 has no effect upon bone yield. At 2°C, Tris-HCl buffer or ethylenediaminetetraacetic acid extracts noncollagenous proteins without loss of bone yield; at 37°C, pH 7.4, these solutions also activate endogenous enzymes and reduce bone yield. The component of bone matrix responsible for reduction in bone yield is separable from bone matrix by extraction with phosphate buffer, by catheptic digestion of bone matrix in acidic buffer solutions, by sequential chemical extraction of noncollagenous proteins with cold slightly acidic salt solutions or by extraction-denaturation with chloroform-methanol. Detergents neither extinguish nor denature the morphogenetic property but some solubilize or extract degradative enzymes; hexodecyl trimethyl ammonium bromide, at pH 5.0, is positively charged and extracts hydrophobic proteins, including part of the bone morphogenetic property. A special selection of sulfhydryl chemical inhibitors remarkably different from the selection inhibiting known enzymes preserves the bone morphogenetic property of bone matrix; p-chloromercuribenzoate preservation is reversible by chemical reactions with cysteine. Reduction in bone yield in phosphate buffer is not attributable to a chemical block because chloroform-methanol extraction of the agent does not restore bone yield and is not attributable to denaturation because bone yield sustained by p-chloromercuribenzoate is lost by chemical reactions with cysteine. An hypothetical insoluble bone morphogenetic protein (BMP) firmly bound to collagen is degraded by a soluble neutral proteinase (BMPase). Digestion of the hypothetical BMP occurs without loss of the 640-A electron micrographic image of bone collagen, resembles tryptic digestion and is more selective as well as physiologic in action.

scholarly journals Isothermal and non-isothermal kinetics of hydrolysis of 1-[2-(2- pentyloxyphenylcarbamoyloxy)-(2-methoxymethyl)-ethyl]- perhydroazepinium chloride (BK 129)

2013 ◽  
Vol 60 (2) ◽  
pp. 43-48
Author(s):  
Stankovičová M. ◽  
Bezáková Ž. ◽  
Beňo P. ◽  
Húšťavová P.
Keyword(s):  
Biological Activity ◽  
Alkaline Hydrolysis ◽  
Functional Group ◽  
Isothermal Kinetics ◽  
Basic Part ◽  
Buffer Solutions ◽  
Kinetics Of Hydrolysis ◽  
Short Time ◽  
Kinetics Of ◽  
Hydrolysis Of

Abstract The substance BK 129 - 1-[2-(2-pentyloxyphenylcarbamoyloxy)-(2-methoxymethyl)-ethyl]-perhydroazepinium chloride was prepared in terms of influence of the connecting chain between the carbamate functional group and the basic part of molecule on biological activity. Such a structural feature is important with regard to its stability. In this work we determined the rate constants of alkaline hydrolysis of this compound at increased temperature under isothermal and non-isothermal conditions. The hydrolysis was also performed in buffer solutions with the purpose of evaluating its stability. Non-isothermal tests of stability enable to reduce the number of analyses. The necessary data for stability of compound are in this way achieved in a short time.

Effect of phosphate buffer on the kinetics of glycation of proteins

2005 ◽  
Vol 18 (2) ◽  
pp. 183-186 ◽  
Author(s):  
Herminia Gil ◽  
Daniel Salcedo ◽  
Rom�n Romero
Keyword(s):  
Phosphate Buffer ◽  
Kinetics Of

The Effect of Phosphatic Composite on Magnesium Phosphate Cement Performance

2014 ◽  
Vol 809-810 ◽  
pp. 477-484
Author(s):  
Zhao Qing Qi ◽  
Hong Tao Wang ◽  
Jun Liang Dang ◽  
Shi Hao Zhang ◽  
Jian Hua Ding
Keyword(s):  
Setting Time ◽  
Potassium Dihydrogen Phosphate ◽  
Magnesium Phosphate ◽  
Dihydrogen Phosphate ◽  
Ammonium Dihydrogen Phosphate ◽  
Hydrogen Phosphate ◽  
Sodium Dihydrogen Phosphate ◽  
Disodium Hydrogen Phosphate ◽  
Potassium Dihydrogen ◽  
Sodium Dihydrogen

The capacity of 10%, 30%, and 50% ammonium dihydrogen phosphate were replaced with an equal amount of three phosphate (potassium dihydrogen phosphate, sodium dihydrogen phosphate, disodium hydrogen phosphate) respectively. Magnesium phosphate cement was made by phosphate of replaced, which strength, setting time, fluidity, hydration temperature, and the hydration products was researched. The results show that: MPC was made that replaced with the equal amount of three kind of phosphate, which has good mechanical properties. Setting time and fluidity change along with the replacment. Three kind of phosphate replace ammonium dihydrogen phosphate, which change the hydration process of MPC. When ammonium dihydrogen phosphate was replaced by an equal amount of disodium hydrogen phosphate, the temperature of hydration is only 69.4 °C. XRD showed that the diffraction peaks of composite’s magnesium phosphate cement increases.

Kinetics of the oxidation of hypophosphorous and phosphorous acids by chromium(VI)

1973 ◽  
Vol 35 (3) ◽  
pp. 901-908 ◽  
Author(s):  
Kalyan K. Sengupta ◽  
J.K. Chakladar ◽  
A.K. Chatterjee
Keyword(s):  
Chromium Vi ◽  
Kinetics Of
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