scholarly journals Investigations on the combustion of hydrocarbons II-Absorption spectra and chemical properties of intermediates

1935 ◽  
Vol 152 (876) ◽  
pp. 378-402 ◽  
Author(s):  
Alfred Rene Jean Paul Ubbelohde ◽  
Alfred Charles Egerton
Keyword(s):  
Absorption Coefficient ◽  
Organic Acids ◽  
Ethyl Acetate ◽  
Induction Period ◽  
Absorption Spectra ◽  
Chemical Properties ◽  
Iron Carbonyl ◽  
Slow Combustion ◽  
Higher Hydrocarbons ◽  
And Chemical Properties

The investigations recorded here are a development of the work of Egerton and Pidgeon on the absorption spectra of burning hydrocarbons, which had included investigations of the absorption and slow combustion of alcohols up to amyl alcohols, aldehydes up to valeraldehyde, acids up to butyric; amylene, ethylene, ethyl acetate, ethyl hydroperoxide, diethyl, peroxide, and of anti-knocks such as lead tetraethyl, iron carbonyl, butyl iodide, and aniline. The results were compared with the slow combustion of the normal hydrocarbons up to pentane, in the same apparatus. The only intermediates which could be demonstrated spectroscopically in the slow combustion of hydrocarbons were formaldehyde and organic acids, mainly because only these substances have a sufficiently large absorption coefficient to he detectable at the concentrations occurring. In addition, a characteristic hand was discovered at the end of the (pseudo) induction period, in the slow combustion of the higher hydrocarbons, though the molecule responsible for it was not identified, in spite of a considerable search among the ordinary products of slow combustion.

scholarly journals On a new Iron carbonyl, and on the action of light and of heat on the Iron carbonyls

1907 ◽  
Vol 79 (527) ◽  
pp. 66-80 ◽  
Keyword(s):  
Liquid Iron ◽  
Carbonyl Iron ◽  
Chemical Properties ◽  
Iron Pentacarbonyl ◽  
Iron Carbonyl ◽  
Physical And Chemical Properties ◽  
Solid Compound ◽  
Iron Carbonyls ◽  
Physical And Chemical ◽  
And Chemical Properties

This paper contains an account of the results of the continuation of the experiments on the action of light on the liquid iron carbonyl (iron penta-carbonyl) and the action of heat on the resulting solid compound, diferro-nonacarbonyl, Fe 2 (CO) 9 , which were described in a paper on “The Physical and Chemical Properties of Iron Carbonyl,” communicated to the Society in 1905. The experiments on the action of light on iron pentacarbonyl under varied conditions have resulted in new and interesting observations, and approximate measurements of the velocity of the reaction induced by light have been made and compared with that of other reactions induced by light.

scholarly journals On the Violence of High Explosive Reactions

2005 ◽  
Vol 127 (1) ◽  
pp. 39-48 ◽  
Author(s):  
Craig M. Tarver ◽  
Steven K. Chidester
Keyword(s):  
High Explosive ◽  
Chemical Properties ◽  
Subsequent Reaction ◽  
Energy Delivery ◽  
Current State ◽  
Slow Combustion ◽  
Shear Heating ◽  
Deposition Processes ◽  
Physical And Chemical ◽  
And Chemical Properties

High explosive reactions can be caused by three general energy deposition processes: impact ignition by frictional and/or shear heating; bulk thermal heating; and shock compression. The violence of the subsequent reaction varies from benign slow combustion to catastrophic detonation of the entire charge. The degree of violence depends on many variables, including the rate of energy delivery, the physical and chemical properties of the explosive, and the strength of the confinement surrounding the explosive charge. The current state of experimental and computer-modeling research on the violence of impact, thermal, and shock-induced reactions is briefly reviewed in this paper.

scholarly journals The absorption spectra of the vapours of benzene and its homologues at different temperatures and pressures, and likewise of solutions of benzene

1908 ◽  
Vol 80 (537) ◽  
pp. 162-165 ◽  
Keyword(s):  
Absorption Spectra ◽  
Chemical Structure ◽  
Constant Pressure ◽  
Chemical Properties ◽  
Complete Agreement ◽  
Physical And Chemical Properties ◽  
Different Temperatures ◽  
Temperature And Pressure ◽  
Physical And Chemical ◽  
And Chemical Properties

The author having been engaged since the year 1877 in investigating and correlating the physical and chemical properties of aromatic substances in relation to their chemical structure or constitution, he has latterly found it desirable that several very definite compounds should be examined in a state of vapour, as well as in solution. The work of E. Pauer, W. Friederichs, and of L. Grebe is referred to in detail. The vapours of benzene and several of its derivatives have been examined (1) at different temperatures and constant pressure; and (2) at different pressures, the temperature being constant. The previous measurements of Pauer, Friederichs, and Grebe have been confirmed, and reconciled where they do not show complete agreement with each other. The records of temperature and pressure, and the shortening of the exposure of the photographic plates, constitute important differences between the work of the former investigators and that of the author.

scholarly journals Use of some biostimulants to improve the growth and chemical constituents of sweet pepper

10.5219/1131 ◽  
2019 ◽  
Vol 13 (1) ◽  
pp. 553-561
Author(s):  
Rabab Maraei ◽  
Noha Eliwa ◽  
Amina Aly
Keyword(s):  
Organic Acids ◽  
Fulvic Acid ◽  
Vegetative Growth ◽  
Foliar Application ◽  
Chemical Constituents ◽  
Chemical Properties ◽  
Sweet Pepper ◽  
Physical And Chemical ◽  
Better Than ◽  
And Chemical Properties

The experiment was conducted during two successive seasons 2016 and 2017 on sweet pepper plants to study the effect of foliar application of some natural extracts (fulvic acid at 2, 4 and 6% or algae at 1, 2 and 4 g.L-1) were applied three times along each season (after 2, 4 and 6 weeks of planting). The influence was evaluated through the response of vegetative growth, and some physical and chemical characteristics of sweet pepper fruits. The results obtained showed that the algae extract at 1 g.L-1 in most cases was better than the other spray treatments investigated to improve most fruit characteristics (length, diameter and yield of fruits), vegetative growth, and chemical properties followed by 6% fulvic acid. With regard to organic acids, malic and citric acids are the main organic acids found in sweet pepper. Malic, succinic and glutaric acids were higher in 1 g.L-1 algae extract treatment, but the concentration of citric acid was higher in 6% fulvic acid treatment. Therefore, algae extract and fulvic acid could be safely recommended as a natural biostimulants application for improving most desirable characteristics of sweet pepper grown under the same experimental condition.

scholarly journals The physical and chemical properties of iron carbonyl

1905 ◽  
Vol 76 (513) ◽  
pp. 558-577 ◽  
Keyword(s):  
Carbon Monoxide ◽  
Chemical Properties ◽  
Iron Pentacarbonyl ◽  
Iron Carbonyl ◽  
Physical And Chemical Properties ◽  
Analogous Compound ◽  
Physical And Chemical ◽  
And Chemical Properties

This paper contains an account, as promised, of a study of the physical and chemical properties of iron carbonyl, similar to that already communicated to the Society on the properties of the analogous compound of nickel,* to which this forms the sequel. The combination of iron and carbon monoxide was discovered by Drs. Mond and Quincke in 1891, and the resulting compound called iron pentacarbonyl was isolated (as a coloured liquid), and examined by Drs. Mond and Langer in the course of the same year.

scholarly journals DEVELOPMENT OF GEL DOSAGE FORM OF ETHYL ACETATE EXTRACT OF MANGOSTEEN RIND

2017 ◽  
Vol 1 (1) ◽  
pp. 28 ◽  
Author(s):  
Ketut Widyani Astuti ◽  
Ni Putu Ayu Dewi Wijayanti ◽  
I Gusti Ngurah Jemmy Anton Prasetia
Keyword(s):  
Ethyl Acetate ◽  
Propylene Glycol ◽  
Dosage Form ◽  
Ethyl Acetate Extract ◽  
Chemical Properties ◽  
Physical And Chemical Properties ◽  
Dispersive Power ◽  
Optimum Formula ◽  
Physical And Chemical ◽  
And Chemical Properties

Abstract Alpha-mangostin is a xanthonoid compound contained in mangosteen rind (Garcinia mangostana L.) and has an antibacterial effect against Staphylococcus aureus, the bacterium that causes acne. In this study, mangosteen rind extract is formulated in a gel dosage form. This study aimed to determine the optimum formula, the physical and chemical properties as well as the optimum formula release profile of the gel dosage form of mangosteen rind extract. The mangosteen rind extract gel formula consists of viscolam, propylene glycol, glycerin, microcare®, ethyl acetate extract of mangosteen rind, and distilled water. The formula was optimized by varying the concentrations of viscolam (2% and 5%), propylene glycol (5% and 20%) and glycerin (2% and 15%) using a factorial experimental design program called Design Expert 7.0.0. The 8 formulas were developed into gel dosage form and the physical and chemical properties were then evaluated. The evaluation tests include viscosity, dispersive power, and pH tests. The evaluation results were processed using the Design Expert 7.0.0 program to determine the optimum formula. The results of the analysis showed the optimum formula of gel dosage form of mangosteen rind extract with viscolam percentage of 4.97%, propylene glycol of 9.91%, glycerin of 12.23%, microcare® of 0.3%, TEA (q.s), ethyl acetate extract of mangosteen rind of 1%, and distilled water of 45%. The evaluation results of the physical and chemical properties of the gel optimum formula revealed the viscosity of 2,345 cps, dispersive power of 6.59 cm, and pH of 6.74. Alpha-mangostin release test on the optimum formula revealed a flux value of 41.327 ?g/cm2/t1/2. From these results, it is concluded that the optimum formula has met the physical and chemical characteristics of a good gel.

Significance of Nonaromatic Organic Acids in Honey

2003 ◽  
Vol 66 (12) ◽  
pp. 2371-2376 ◽  
Author(s):  
INÉS MATO ◽  
JOSÉ F. HUIDOBRO ◽  
JESÚS SIMAL-LOZANO ◽  
M. TERESA SANCHO
Keyword(s):  
Organic Acids ◽  
Current Literature ◽  
Antioxidant Activities ◽  
Chemical Properties ◽  
Antibacterial Activities ◽  
Physical And Chemical Properties ◽  
Physical And Chemical ◽  
And Chemical Properties

Although organic acids represent <0.5% of honey's constituents, they make important contributions to the organoleptic, physical, and chemical properties of honey. To date, approximately 30 nonaromatic organic acids have been identified in honey, but relatively little attention has been paid to these components. This article reviews the current literature related to the significance of nonaromatic organic acids in honey; it was written with a goal of attracting researchers to study these interesting honey components. Previous research contributions on nonaromatic organic acids in honey may be classified into five main areas: (i) the antibacterial activities of these acids, (ii) the antioxidant activities of these acids, (iii) the use of these acids as possible indicators of incipient fermentation, (iv) the use of these acids for treatment of Varroa infestation, and (v) the use of these acids as factors for the characterization of both botanical and geographical origins of honeys. We conclude that nonaromatic organic acids are of interest for diverse reasons and that there is a particular need for studies regarding their possible antibacterial and antioxidant activities.

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