THE LIMITING EQUIVALENT CONDUCTANCES OF AMMONIUM CHLORIDE, AMMONIUM BROMIDE, AND AMMONIUM NITRATE AT 35.00 °C.

1958 ◽  
Vol 36 (2) ◽  
pp. 330-338 ◽  
Author(s):  
A. N. Campbell ◽  
E. Bock
Keyword(s):  
Aqueous Solutions ◽  
Ammonium Nitrate ◽  
Ammonium Chloride ◽  
Stokes Equation ◽  
Probable Error ◽  
Ammonium Bromide ◽  
Conductance Data ◽  
Ionic Conductances ◽  
Hydrolysis Of ◽  
Limiting Equivalent Conductances

The limiting equivalent conductances of ammonium chloride, ammonium bromide, and ammonium nitrate as well as the limiting ionic conductances of the ammonium and nitrate ions were determined at 35 °C. with a probable error of 0.05%. The values found were [Formula: see text] 180.97 mhos, [Formula: see text] 182.73 mhos, [Formula: see text] 174.21 mhos, [Formula: see text] 88.73 mhos, and [Formula: see text] 85.48 mhos. These values were obtained by the application of the Shedlovsky method of extrapolation to equivalent conductance data, which had been corrected for the hydrolysis of the ammonium ion.Observed equivalent conductances of aqueous solutions of ammonium nitrate at 35 °C., in the concentration range from 0.0002 N to 10 N, have been compared with those calculated by means of the Wishaw–Stokes and Falkenhagen–Leist equations. The Wishaw–Stokes equation was found to give better agreement with experiment than the Falkenhagen–Leist equation.

CONDUCTANCES OF AQUEOUS SOLUTIONS OF SODIUM HEXANOATE (SODIUM CAPROATE) AND THE LIMITING CONDUCTANCES OF THE HEXANOATE ION, AT 25 °C AND 35 °C

1960 ◽  
Vol 38 (10) ◽  
pp. 1939-1945 ◽  
Author(s):  
A. N. Campbell ◽  
J.I. Friesen
Keyword(s):  
Molecular Weight ◽  
Aqueous Solutions ◽  
Stokes Equation ◽  
Apparent Molecular Weight ◽  
Ionic Micelles ◽  
Limiting Conductances ◽  
Limiting Equivalent Conductances

The equivalent conductances, densities, and viscosities of aqueous solutions of sodium hexanoate have been determined at 25 °C and 35 °C at concentrations ranging from 0.0003 M to saturation.The limiting equivalent conductances of the hexanoate ion have been determined as 27.37 ± 0.04 mhos at 25 °C and 34.69 ± 0.05 mhos at 35 °C.The Robinson–Stokes and the Falkenhagen–Leist equations have been applied to the data. The Robinson–Stokes equation reproduces the data within 0.7 mho up to 0.5 M at 25 °C when å = 13 Å. At 35 °C the data are reproduced within 0.5 mho up to 0.05 M with å = 10 Å. The Falkenhagen–Leist equation reproduces the data at 25 °C within 0.4 mho up to 0.1 M with å = 5.5 Å. An å = 4.0 Å reproduces the 35 °C data within 0.5 mho up to 0.05 M.From the form of the conductance curves and from an estimation of the apparent molecular weight it was concluded that the hexanoate ion does not form ionic micelles.

Alkaline Hydrolysis of Substituted Phenyl Acetates Catalyzed by Quaternary Ammonium Salts

1993 ◽  
Vol 58 (12) ◽  
pp. 2891-2895 ◽  
Author(s):  
Jiří Kulič ◽  
Jiří Sussenbek ◽  
Aleš Ptáček
Keyword(s):  
Ammonium Chloride ◽  
Alkaline Hydrolysis ◽  
Quaternary Ammonium Salts ◽  
Ammonium Salts ◽  
Ammonium Bromide ◽  
Hexadecyltrimethylammonium Bromide ◽  
Rate Data ◽  
Hammett Equation ◽  
Efficient Catalyst ◽  
Hydrolysis Of

Alkaline hydrolysis if the phenyl acetates CH3COOC6H4X (X = 4-NO2, 3-NO2, 3-Cl, H, 4-CH3, 3-CH3, and 4-OCH3) in the presence of hexadecyltris(2-hydroxyethyl)ammonium chloride, bis(2-hydroxyethyl)hexadecyl(methyl)ammonium bromide, and hexadecyltrimethylammonium bromide has been studied. Comparison of the rates of the hydrolysis for the above tenzides showed that the most efficient catalyst is the hexadecyltris(2-hydroxyethyl)ammonium chloride. In all cases, the rate data correlated well with structure effects by the Hammett equation.

The enthalpy of solution of ammonia in water and in aqueous solutions of ammonium chloride and ammonium bromide

1974 ◽  
Vol 6 (6) ◽  
pp. 565-570 ◽  
Author(s):  
R.D Worswick ◽  
A.G Dunn ◽  
L.A.K Staveley
Keyword(s):  
Aqueous Solutions ◽  
Ammonium Chloride ◽  
Enthalpy Of Solution ◽  
Ammonium Bromide

The Effects of Amines on the Esterase Activities of Thrombin and Thrombokinase and on Several Clotting Tests

1974 ◽  
Vol 31 (02) ◽  
pp. 309-318
Author(s):  
Phyllis S Roberts ◽  
Raphael M Ottenbrite ◽  
Patricia B Fleming ◽  
James Wigand
Keyword(s):  
Choline Chloride ◽  
Polymerization Process ◽  
Ammonium Bromide ◽  
Bovine Thrombin ◽  
One Stage ◽  
Human Proteins ◽  
Rate Of Hydrolysis ◽  
The One ◽  
Hydrolysis Of Esters ◽  
Hydrolysis Of

Summary1. Choline chloride, 0.1 M (in 0.25 M Tris. HCl buffer, pH 7.4 or 8.0, 37°), doubles the rate of hydrolysis of TAME by bovine thrombokinase but has no effect on the hydrolysis of this ester by either human or bovine thrombin. Only when 1.0 M or more choline chloride is present is the hydrolysis of BAME by thrombokinase or thrombin weakly inhibited. Evidence is presented that shows that these effects are due to the quaternary amine group.2. Tetramethyl ammonium bromide or chloride has about the same effects on the hydrolysis of esters by these enzymes as does choline chloride but tetra-ethyl, -n.propyl and -n.butyl ammonium bromides (0.1 M) are stronger accelerators of the thrombokinase-TAME reaction and they also accelerate, but to a lesser degree, the thrombin-TAME reaction. In addition, they inhibit the hydrolysis of BAME by both enzymes. Their effects on these reactions, however, do not follow any regular order. The tetraethyl compound is the strongest accelerator of the thrombokinase-TAME reaction but the tetra-ethyl and -butyl compounds are the strongest accelerators of the thrombin-TAME reaction. The ethyl and propyl compounds are the best (although weak) inhibitors of the thrombokinase-BAME and the propyl compound of the thrombin-BAME reactions.3. Tetra-methyl, -ethyl, -n.propyl and -n.butyl ammonium bromides (0.01 M) inhibit the clotting of fibrinogen by thrombin (bovine and human proteins) at pH 7.4, imidazole or pH 6.1, phosphate buffers and they also inhibit, but to a lesser degree, a modified one-stage prothrombin test. In all cases the inhibition increases regularly as the size of the alkyl group increases from methyl to butyl. Only the ethyl com pound (0.025 M but not 0.01 M), however, significantly inhibits the polymerization of bovine fibrin monomers. It was concluded that inhibition of the fibrinogen-thrombin and the one-stage tests by the quaternary amines is not due to any effect of the com pounds on the polymerization process but probably due to inhibition of thrombin’s action on fibrinogen by the quaternary amines.

Viscosity, electrical conductivity and density of the system ammonium nitrate-dimethyl sulphoxide

1984 ◽  
Vol 49 (5) ◽  
pp. 1109-1115
Author(s):  
Jindřich Novák ◽  
Zdeněk Kodejš ◽  
Ivo Sláma
Keyword(s):  
Electrical Conductivity ◽  
Aqueous Solutions ◽  
Ammonium Nitrate ◽  
Transport Properties ◽  
Calcium Nitrate ◽  
Dimethyl Sulphoxide ◽  
Present System ◽  
Empirical Equations ◽  
Concentrated Solutions ◽  
Nitrate Solutions

The density, viscosity, and electrical conductivity of highly concentrated solutions of ammonium nitrate in dimethyl sulphoxide have been determined over the temperature range 10-60 °C and the concentration range 7-50 mol% of the salt. The variations in the quantities as a function of temperature and concentration have been correlated by empirical equations. A comparison is made between the transport properties for the present system, aqueous solutions of ammonium nitrate, and calcium nitrate solutions in dimethyl sulphoxide.

scholarly journals Generation of highly amenable cellulose-Iβ via selective delignification of rice straw using a reusable cyclic ether-assisted deep eutectic solvent system

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Chiranjeevi Thulluri ◽  
Ravi Balasubramaniam ◽  
Harshad Ravindra Velankar
Keyword(s):  
Enzymatic Hydrolysis ◽  
Rice Straw ◽  
Deep Eutectic Solvent ◽  
Solvent System ◽  
Cyclic Ether ◽  
Cellulolytic Enzymes ◽  
Ammonium Bromide ◽  
Selective Delignification ◽  
Cellulose Iβ ◽  
Hydrolysis Of

AbstractCellulolytic enzymes can readily access the cellulosic component of lignocellulosic biomass after the removal of lignin during biomass pretreatment. The enzymatic hydrolysis of cellulose is necessary for generating monomeric sugars, which are then fermented into ethanol. In our study, a combination of a deep eutectic (DE) mixture (of 2-aminoethanol and tetra-n-butyl ammonium bromide) and a cyclic ether (tetrahydrofuran) was used for selective delignification of rice straw (RS) under mild conditions (100 °C). Pretreatment with DE-THF solvent system caused ~ 46% delignification whereas cellulose (~ 91%) and hemicellulose (~ 67%) recoveries remained higher. The new solvent system could be reused upto 10 subsequent cycles with the same effectivity. Interestingly, the DE-THF pretreated cellulose showed remarkable enzymatic hydrolysability, despite an increase in its crystallinity to 72.3%. Contrary to conventional pretreatments, we report for the first time that the enzymatic hydrolysis of pretreated cellulose is enhanced by the removal of lignin during DE-THF pretreatment, notwithstanding an increase in its crystallinity. The current study paves way for the development of newer strategies for biomass depolymerization with DES based solvents.

Kinetic studies on the rate of hydrolysis of N-ethyl-N′-(dimethylaminopropyl)carbodiimide in aqueous solutions using mass spectrometry and capillary electrophoresis

2002 ◽  
Vol 310 (1) ◽  
pp. 122-124 ◽  
Author(s):  
Q Paula Lei ◽  
David H Lamb ◽  
Ron K Heller ◽  
Anthony G Shannon ◽  
Robert Ryall ◽  
...  
Keyword(s):  
Mass Spectrometry ◽  
Capillary Electrophoresis ◽  
Aqueous Solutions ◽  
Kinetic Studies ◽  
Rate Of Hydrolysis ◽  
Hydrolysis Of
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