A preliminary investigation of the structure of green wattle tannin (acacia decurrens willd)
- Authors: Glueck, Leonard David
- Date: 1952
- Subjects: Tannins , Tannin plants
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4475 , http://hdl.handle.net/10962/d1011988 , Tannins , Tannin plants
- Description: Green wattle tannin extracts were separated by lead salt precipitation into a phenolic tannin fraction and a nontannin fraction. The combustion analysis of the tannin fraction corresponded to an empirical formula C₁₅H₁₄O₆. Methoxy and acetyl values showed four oxygens were hydroxy groups while the residual oxygens could either be ether linked or carbonyl groups. Diazomethane methylation produced a white product of high methoxyl value which indicated that the four hydroxyl groups were phenolic. Chromatography of the lead salt purified tannin showed an indistinct non-fluorescent trail. Ether extraction of the tannin removed the associated Phenolic bodies. The ethereal extract unlike black wattle extracts contained no fisetin and evaporation of the ethereal solutions yielded a gummy non-crystalline residue. Alkaline fusion of the purified tannin produced for the first tlme a variety of acidic and phenolic compounds i.e. resorcinol, pyrogaloll, phloroglucinol β-resorcylic acid, gallic acid and protocatechuic acid. From the high yields of resorcinol (6%) and gallic acid (3%), these units appear to predominate. These degradation productions, coupled with the analytical figures, indicate a possible C₁₅ unit with resorcinol and pyrogallol nuclei as a basis. The non-tannin fraction failed to reveal any compound which might cause the excessive redness in green wattle extracts. Chromatography of this non-tannin fraction showed the presence of sucrose.
- Full Text:
- Date Issued: 1952
- Authors: Glueck, Leonard David
- Date: 1952
- Subjects: Tannins , Tannin plants
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4475 , http://hdl.handle.net/10962/d1011988 , Tannins , Tannin plants
- Description: Green wattle tannin extracts were separated by lead salt precipitation into a phenolic tannin fraction and a nontannin fraction. The combustion analysis of the tannin fraction corresponded to an empirical formula C₁₅H₁₄O₆. Methoxy and acetyl values showed four oxygens were hydroxy groups while the residual oxygens could either be ether linked or carbonyl groups. Diazomethane methylation produced a white product of high methoxyl value which indicated that the four hydroxyl groups were phenolic. Chromatography of the lead salt purified tannin showed an indistinct non-fluorescent trail. Ether extraction of the tannin removed the associated Phenolic bodies. The ethereal extract unlike black wattle extracts contained no fisetin and evaporation of the ethereal solutions yielded a gummy non-crystalline residue. Alkaline fusion of the purified tannin produced for the first tlme a variety of acidic and phenolic compounds i.e. resorcinol, pyrogaloll, phloroglucinol β-resorcylic acid, gallic acid and protocatechuic acid. From the high yields of resorcinol (6%) and gallic acid (3%), these units appear to predominate. These degradation productions, coupled with the analytical figures, indicate a possible C₁₅ unit with resorcinol and pyrogallol nuclei as a basis. The non-tannin fraction failed to reveal any compound which might cause the excessive redness in green wattle extracts. Chromatography of this non-tannin fraction showed the presence of sucrose.
- Full Text:
- Date Issued: 1952
A study of cation exchange in South African soils
- Authors: Du Toit, A A
- Date: 1952
- Subjects: Soil chemistry , Ion exchange
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4462 , http://hdl.handle.net/10962/d1011506 , Soil chemistry , Ion exchange
- Description: The colloidal fraction is the vital part of a soil. These extremely minute particles determine the nature of the soil and are mainly responsible for its many and varied functions. The most important of these functions is perhaps the ability of the colloids to adsorb and exchange cations, the elements so essential to all organisms as building materials. When pure water is passed through a non-saline. soil, the leachate will contain very few dissolved cations. If, on the other hand, an electrolyte such as a weak solution of sodiun chloride, is passed through the same soil, the leachate will contain considerable quantities of calcium, magnesium and potassiun chlorides as well as much of the original sodium chloride. The number of equivalents of the cations collected will be approximately the same as the number of equivalents of sodium ions added. Sodium ions have displaced some of the calcian, magnesium and potassium ions from the soil. This phenomenon is known as cation exchange. Intro., p. 1.
- Full Text:
- Date Issued: 1952
- Authors: Du Toit, A A
- Date: 1952
- Subjects: Soil chemistry , Ion exchange
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4462 , http://hdl.handle.net/10962/d1011506 , Soil chemistry , Ion exchange
- Description: The colloidal fraction is the vital part of a soil. These extremely minute particles determine the nature of the soil and are mainly responsible for its many and varied functions. The most important of these functions is perhaps the ability of the colloids to adsorb and exchange cations, the elements so essential to all organisms as building materials. When pure water is passed through a non-saline. soil, the leachate will contain very few dissolved cations. If, on the other hand, an electrolyte such as a weak solution of sodiun chloride, is passed through the same soil, the leachate will contain considerable quantities of calcium, magnesium and potassiun chlorides as well as much of the original sodium chloride. The number of equivalents of the cations collected will be approximately the same as the number of equivalents of sodium ions added. Sodium ions have displaced some of the calcian, magnesium and potassium ions from the soil. This phenomenon is known as cation exchange. Intro., p. 1.
- Full Text:
- Date Issued: 1952
Attempted synthesis of a [beta] or [gamma] resorcinyl alcohol
- Authors: Ryding, William Wallace
- Date: 1952
- Subjects: Alcohol -- Synthesis , Resorcinol
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4517 , http://hdl.handle.net/10962/d1014134
- Description: The ultimate objective of this research is the elucidation of the mechanism of the resorcinol-formaldehyde condensation. Whilst a vast literature has been built up about the phenol- formaldehyde condensation, that of resorcinol has received but scant attention, probably because the high reactivity of resorcinol rendered the following of the condensation extremely difficult. The earliest observation concerning the resorcinol-formaldehyde condensation was due to Baeyer who, in 1872, condensed resorcinol with various aldehydes. When the aldehyde was relatively inactive crystalline compounds were obtalned but with acetaldehyde or formaldehyde a resinous product resulted. In 1892 Caro condensed an excess ot resorcinol with formaldehyde in the presence of dilute hydrochloric acid; the product obtained recrystallised from alcohol as white microsoopic crystals, decomposed without melting at 250° and was stated to be bis (2- 4 dihydroxyphenyl) methane ... In decidlng upon the most suitable lines of attack it would seem that a survey of the literature relating to the phenol-formaldehyde concentration which might be expected to be closely related to that of resorcinol, would be of value. Summary of p. 1-5
- Full Text:
- Date Issued: 1952
- Authors: Ryding, William Wallace
- Date: 1952
- Subjects: Alcohol -- Synthesis , Resorcinol
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4517 , http://hdl.handle.net/10962/d1014134
- Description: The ultimate objective of this research is the elucidation of the mechanism of the resorcinol-formaldehyde condensation. Whilst a vast literature has been built up about the phenol- formaldehyde condensation, that of resorcinol has received but scant attention, probably because the high reactivity of resorcinol rendered the following of the condensation extremely difficult. The earliest observation concerning the resorcinol-formaldehyde condensation was due to Baeyer who, in 1872, condensed resorcinol with various aldehydes. When the aldehyde was relatively inactive crystalline compounds were obtalned but with acetaldehyde or formaldehyde a resinous product resulted. In 1892 Caro condensed an excess ot resorcinol with formaldehyde in the presence of dilute hydrochloric acid; the product obtained recrystallised from alcohol as white microsoopic crystals, decomposed without melting at 250° and was stated to be bis (2- 4 dihydroxyphenyl) methane ... In decidlng upon the most suitable lines of attack it would seem that a survey of the literature relating to the phenol-formaldehyde concentration which might be expected to be closely related to that of resorcinol, would be of value. Summary of p. 1-5
- Full Text:
- Date Issued: 1952
Investigation leading to a process for the synthesis of hydrogen sulphide from sulphur and certain lubricating oils derived from petroleum
- Authors: Schauder, H
- Date: 1952
- Subjects: Hydrogen sulfide
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4499 , http://hdl.handle.net/10962/d1013160
- Description: The primary object of the present study was to provide a process adaptable to prevailing South African conditions, for the manufacture of hydrogen sulphide. Such a process would also be suitable for use in other countries where the gas is not obtainable naturally or from refinery operations or as a by-product from other industries. Early in the study it was found that the literature embodying prior work was very scattered in character and had to be sought in many different fields of research. It was therefore decided to make the record of prior work as comprehensive as possible so as to provide, at the same time, a starting point tor future workers on related subjects. Intro., p. 1.
- Full Text:
- Date Issued: 1952
- Authors: Schauder, H
- Date: 1952
- Subjects: Hydrogen sulfide
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4499 , http://hdl.handle.net/10962/d1013160
- Description: The primary object of the present study was to provide a process adaptable to prevailing South African conditions, for the manufacture of hydrogen sulphide. Such a process would also be suitable for use in other countries where the gas is not obtainable naturally or from refinery operations or as a by-product from other industries. Early in the study it was found that the literature embodying prior work was very scattered in character and had to be sought in many different fields of research. It was therefore decided to make the record of prior work as comprehensive as possible so as to provide, at the same time, a starting point tor future workers on related subjects. Intro., p. 1.
- Full Text:
- Date Issued: 1952
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