scholarly journals An Innovative Technique of Liquid Purity Analysis and Its Application to Analysis of Water Concentration in Alcohol-Water Mixtures and Studies on Change of Activation Energies of the Mixtures

2012 ◽  
Vol 4 (4) ◽  
Author(s):  
Dilip K. De ◽  
A. B. Dikko
Keyword(s):  
Water Concentration ◽  
Activation Energies ◽  
Innovative Technique ◽  
Alcohol Water ◽  
Purity Analysis

Solvent structure effects on solvated electron reactions with ions in 2-butanol/water mixed solvents

1991 ◽  
Vol 69 (5) ◽  
pp. 884-892 ◽  
Author(s):  
Sedigallage A. Peiris ◽  
Gordon R. Freeman
Keyword(s):  
Rate Constant ◽  
Pure Water ◽  
Mixed Solvents ◽  
Reaction Rates ◽  
Bimolecular Reaction ◽  
Activation Energies ◽  
Solvated Electron ◽  
Polar Species ◽  
Water Solvent ◽  
Alcohol Water

The Smoluchowski–Debye–Stokes–Einstein equation for the rate constant k2 of a bimolecular reaction between charged or polar species[Formula: see text]was used to evaluate effects of bulk solvent properties on reaction rates of solvated electrons with [Formula: see text] and [Formula: see text] in 2-butanol/water mixed solvents. To explain detailed effects it was necessary to consider more specific behavior of the solvent. Rate constants k2, activation energies E2, and pre-exponential factors A2 of these reactions vary with the composition of 2-butanol/water mixtures. The values of E2 were in general similar to activation energies of ionic conductance EΛ0 of the solutions, except for much higher values of E2 of [Formula: see text] in alcohol-rich solvents and of [Formula: see text] in pure water solvent. The solvent apparently participates chemically in the [Formula: see text] reaction, and the [Formula: see text] reaction is multistep. Rate constant and conductance measurements of thallium acetate solutions in 2-butanol containing zero and 10 mol% water were complicated by the formation of ion clusters larger than pairs. Key words: alcohol/water mixed solvents, ions, reaction kinetics, solvated kinetics, solvated electron, solvent effects.

A Comparison of Structures and Crystallization Behavior of Gels, Gel-Derived Classes and Conventional Glasses

1986 ◽  
Vol 73 ◽  
Author(s):  
Shyama P. Mukherjee
Keyword(s):  
Kinetic Parameters ◽  
Crystallization Behavior ◽  
Water Concentration ◽  
Processing Parameters ◽  
Activation Energies ◽  
Crystallization Behaviors ◽  
Gel Processing

ABSTRACTStudies on the structures and crystallization behavior of gels in TiO2, GeO2, SiO2-GeO2 and PbO-GeO2 systems are presented to analyze the differences in structures and crystallization behavior of gel-derived glasses and conventional glasses. The kinetic parameters for crystallization such as activation energies and frequency factors of gels, gel-derived glasses and conventional glasses in the GeO2-PbO system are presented to elucidate their difference in nucleation and crystallization behaviors. The influence of gel processing parameters such as pH and water concentration on the crystallization behavior of gels are discussed.

REACTIONS OF ARYLSULPHONIC ESTERS: V. AN INTERPRETATION OF ACTIVATION ENERGIES OF SOLVOLYSIS OF METHYL BENZENESULPHONATE IN MIXED HYDROXYLIC SOLVENTS

1956 ◽  
Vol 34 (7) ◽  
pp. 931-941 ◽  
Author(s):  
J. B. Hyne ◽  
R. E. Robertson
Keyword(s):  
Activation Energy ◽  
Reaction Mechanism ◽  
Aliphatic Alcohol ◽  
Activation Energies ◽  
Physical Significance ◽  
Activation Entropy ◽  
Experimental Uncertainty ◽  
Extended Form ◽  
Uncertainty Product ◽  
Alcohol Water

The rates of solvolysis of methyl benzenesulphonate at 50 ° and 75 °C. in several binary aliphatic alcohol–water mixtures have been determined over the composition ranges. The derived activation energies are compared with those calculated from an extended form of the equation employed in accounting for solvolytic activation energies in pure hydroxylic solvents. The physical significance of the equation is discussed in terms of a spectrum of solvolytic mechanisms covering the range between SN1 and SN2 mechanisms. The equation predicts activation energy values well within the experimental uncertainty. Product ratio and activation entropy data are shown to be in keeping with the reaction mechanism proposed.

Deep level study in epitaxial 4H-SiC grown on substrates inclined toward

2002 ◽  
Vol 719 ◽  
Author(s):  
Masashi Kato ◽  
Masaya Ichimura ◽  
Eisuke Arai ◽  
Shigehiro Nishino
Keyword(s):  
Deep Level Transient Spectroscopy ◽  
Deep Level ◽  
Activation Energies ◽  
Thickness Dependence ◽  
Epitaxial Layers ◽  
Transient Spectroscopy

AbstractEpitaxial layers of 4H-SiC are grown on (0001) substrates inclined toward <1120> and <1100> directions. Defects in these films are characterized by deep level transient spectroscopy (DLTS) in order to clarify the dependence of concentrations and activation energies on substrate inclination. DLTS results show no such dependence on substrate inclination but show thickness dependence of the concentration.

Determination of δ-hexadecansultone in sodium α-olefinesulphonates and liquid detergents using gas chromatography-mass spectrometry (GC/MS)

2019 ◽  
Vol 85 (7) ◽  
pp. 16-21
Author(s):  
Liliya R. Mubarakova ◽  
German K. Budnikov
Keyword(s):  
Multicomponent Mixture ◽  
Operating Mode ◽  
Complete Separation ◽  
Gas Chromatography Mass Spectrometry ◽  
Liquid Detergent ◽  
Cyclic Esters ◽  
Alcohol Water ◽  
Household Chemicals ◽  
Hydrolysis Of

Sultones are cyclic esters of hydroxysulfonic acids, which are formed in the process of sulfonation of α-olefins with sulfur trioxide gas. More stable sultones may be present in the final product — an anionic surfactant — sodium α-olefin sulfonate (AOC-Na). AOC-Na is widely used in the production of household chemicals and cosmetic products, including liquid dishwashing detergents. Sultones are strong skin sensitizers, their level in AOC-Na should be strictly controlled and not exceed 5 ppm. Operational and strict control of the sultone content upon AOC-Na production allows timely adjustment at the stage of hydrolysis, which leads to a more complete disclosure of the sultone cycle with the formation of the corresponding olefin sulfonates and hydroxyalkanesulfonates. We propose a method for determining δ-hexadecansultone in liquid dishwashing detergents and sodium α-olefinsulfonates obtained on the basis of α-olefins of C14 – C16 fractions using GC/MS, which provides shortening of sample preparation and keeps the sensitivity with a detection limit of 0.02 mg/kg. The effect of various weakly polar and non-polar organic solvents used for Sultone extraction from AOC-Na and liquid detergent on liquid extraction based on the dispersion of the extractant in an alcohol/water phase is studied. When selecting the solvent we have shown that the use of diethyl ether provided the best extraction of the analyte. Determination of the analyte extraction recovery was performed using the reaction of hydrolysis of the extracted mixture. We specified the operating mode of the device which provided complete separation of the components of the analyzed compounds including the samples of liquid detergent for dishes being a multicomponent mixture of complex composition.

Pertumbuhan Dan Perkembangan Anggrek Dendrobium anosmum Pada Media Kultur In Vitro Dengan Beberapa Konsentrasi Air Kelapa

Agrologia ◽  
2018 ◽  
Vol 1 (1) ◽  
Author(s):  
S. Tuhuteru ◽  
Meity L Hehanussa ◽  
Simon H.T Raharjo
Keyword(s):  
Culture Medium ◽  
Culture Media ◽  
Water Concentration ◽  
Medium Composition ◽  
Coconut Water ◽  
Orchid Species ◽  
Randomized Design ◽  
Wet Weight ◽  
Completely Randomized Design

Dendrobium anosmum is one of natural orchids in Indonesia. Optimization of medium composition for orchid propagation through in vitro culture is necessary to enhance propagule multiplication capabilities and quality. This study was aimed to study the influence of concentration of coconut water in culture medium on in vitro growth and development of D. anosmum orchid species and to determine the optimal coconut water concentration in culture media.  The experiment were arranged in a Completely Randomized Design with four treatments and eight replications. The treatments consisted of the addition of coconut water with concentrations: 0 ml•l -1 (control), 50 ml•l-1, 100 ml•l-1 and 150 ml•l-1. The results showed that addition of coconut water in culture medium gave different effect on shoot growth and multiplication of D. anosmum orchids.  Coconut water concentration of 100 ml•l-1 was the best concentration for growth and multiplication of D. anosmum orchids, based on both shoots and roots growth, plantlet height and wet weight.

THE SOURCES OF AUXIN HORMONE TO GROWTH OF SHOOT PINEAPPLE STEM CUTTING (Ananascomosus.L. Merr.)

2016 ◽  
Vol 1 (1) ◽  
pp. 45-52
Author(s):  
Palupi Puspitorini
Keyword(s):  
Water Concentration ◽  
Urine Concentration ◽  
Experimental Results ◽  
Stem Cuttings ◽  
Randomized Design ◽  
Natural Hormone ◽  
Cow Urine ◽  
Urine Concentrations ◽  
Completely Randomized Design ◽  
Better Than

The aim of this study was to select the best sources of auxin of which it can stimulate the growth of shoots Pineapple plant cuttings. This research is compiled in a completely randomized design (CRD) with 4 treatments and 6 replications. The Data were statistically Analyzed by the DMRT. Level of treatment given proves that no treatment 0%, cow urine concentration of 25%, young coconut water concentration of 25% and Rootone F 100 mg / cuttings. The results showed that cow urine concentrations of 25% and Rootone F 100 mg give the best results in stimulating the growth of shoots pineapple stem cuttings. Experimental results concluded that the effect of this natural hormone were better than the shoots without given hormone.           

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