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Detalles de la revista
Formato
Revista
eISSN
2719-9509
Publicado por primera vez
01 Jan 1992
Periodo de publicación
4 veces al año
Idiomas
Inglés

Buscar

Volumen 5 (1970): Edición 6 (December 1970)

Detalles de la revista
Formato
Revista
eISSN
2719-9509
Publicado por primera vez
01 Jan 1992
Periodo de publicación
4 veces al año
Idiomas
Inglés

Buscar

12 Artículos
Acceso abierto

Irrigation Experiments on Oriental Tobacco

Publicado en línea: 12 Jul 2014
Páginas: 259 - 261

Resumen

Abstract

Irrigation experiments were conducted at the Tobacco Institute of Drama and the Tobacco Research Station of Xanthi on aromatic and on neutral (Kaba-Koulak) tobacco. Both tobacco types benefited highly from a moderate water supply from 40-80 m3 per stremma. Yield was increased by about 20-30 % and quality was also significantly improved. Nicotine content was reduced in a proportion of 5-10 %. In the aromatic types, topping and close spacing gave significantly higher yield per stremma The nicotine level was higher with topping and lower with close spacing

Acceso abierto

''Ripening'' Tobacco with the Ethylene-Releasing Agent 2-Chloroethylphosphonic Acid

Publicado en línea: 12 Jul 2014
Páginas: 262 - 265

Resumen

Abstract

Treatment of flue-cured tobacco with the ethylene releasing agent 2-chloroethylphosphonic acid (CEPA) caused mature leaves to lose their green colour and turn yellow. The treated leaves appeared to go through a partial "yellowing'' or "colouring" phase prior to harvest. Treated leaves at harvest contained greater amounts of reducing sugars and lower levels of starch, relative to comparable untreated leaves. At the end of the curing process, comparisons between treated and untreated leaf showed that only small differences existed in total nitrogen, total alkaloids, starch, and reducing sugars. Statistically, protein of leaf treated with CEPA was significantly lower as compared to untreated leaf. For all yellowing times, dollar values per hundred weight of cured leaf from treated plants were higher than from untreated plants, but the average weight per leaf from treated plants was lower. During the curing process, leaf treated with CEPA can probably be subjected to shorter periods of yellowing or colouring than untreated leaf. If further work with "ripening'' chemicals such as CEPA show that they can be used to hasten yellowing or ripen tobacco successfully, as well as to reduce the time required for curing the crop, economic advantages are likely to accrue. It is to be hoped that such chemicals may help reduce the labour and investment required for crop production, and at the same time improve crop quality

Acceso abierto

Tobacco Chemistry. 3: Unsaturated Hydrocarbon Constituents of Greek Tobacco

Publicado en línea: 12 Jul 2014
Páginas: 266 - 274

Resumen

Abstract

Tobacco from Serres, Greece, has been studied with respect to the content of unsaturated hydrocarbons. The isolation of these constituents involved as a key step distillation with the aid of a new technique using carbon dioxide as carrier gas and total condensation of this and the distillate at liquid nitrogen temperature. In addition to the main constituent, neophytadiene, the unsaturated hydrocarbon fraction was shown to contain a series of aromatic compounds. These were examined by means of gas chromatography on capillary columns and also by gas chromatography in combination with mass spectrometry. Fractions were examined before and after elimination of smaller amounts of accompanying olefinic material with the aid of osmium tetroxide. The aromatic constituents were found to be alkylated benzene and naphthalene derivatives, of which many have been identified unambiguously. The vast majority of these have not previously been encountered in tobacco. Several have, however, been detected in smoke and the present results therefore show that these compounds are not necessarily formed solely in the pyrolysis process

Acceso abierto

Principal Aliphatic Secondary Amines of Burley Tobacco

Publicado en línea: 12 Jul 2014
Páginas: 275 - 278

Resumen

Abstract

Quantity and distribution of the principal aliphatic secondary amines - dimethylamine, methylethylamine, diethylamine, and methylpropylamine - varied within plant tissue and among Nicotiana spp. In Burley tobacco the stem tissue had the highest content of these amines and the leaf midrib the lowest. Leaf lamina, roots and seed were intermediate in amine content. Among Nicotiana spp. there was considerable difference in total amine content as well as among the ratios of the amine fractions measured. Amine content of tissue was positively correlated with nitrogen content of tissue and was altered by the drying process of tissue prior to analysis. The amines were not present as free amines or salts but were detected only following steam distillation from a basic medium

Acceso abierto

Changes of Alkaloid Composition During Curing in Three lsogenic Burley Tobaccos and Their F1 Hybrids

Publicado en línea: 12 Jul 2014
Páginas: 279 - 284

Resumen

Abstract

Quantitative changes of nicotine, nornicotine, anabasine (including anatabine), and total alkaloids in the juvenile leaves and roots of Nicotiana tabacum cv. Burley 21 (HN) and its isogenic lines selected for nicotine conversion (C), and low total alkaloids (LN) were studied during air-curing simulation. In the leaf, the C line contained less total alkaloids but more nornicotine than the HN line, suggesting that some may have been converted to nornicotine during leaf growth. The conversion phenomenon was not observed in the root. The root tissues of the LN line showed a high rate of nicotine decomposition at the inception of curing. On the basis of F1 results, both total alkaloids and nicotine conversion are governed by dominant factors. An intermediate nornicotine / nicotine ratio for the cured leaves of the LN and C hybrids indicated the presence of converter modifiers in the LN line. In the C line and its hybrids the decrease of nicotine content mainly occurred at the beginning of curing, whereas the nornicotine increase appeared after the eighth day of curing. The amount of anabasine was increased in the leaf but was decreased in the roots by curing

Acceso abierto

Electrophoretic Patterns of Soluble Proteins in Tobacco Leaf During Curing

Publicado en línea: 12 Jul 2014
Páginas: 285 - 289

Resumen

Abstract

Polyacrylamide gel disc electrophoresis revealed at least 13 anodic protein bands in leaf extracts of seven tobacco (Nicotiana tabacum L.) strains representing Burley, Turkish, flue- and fire-cured types. Four major bands B, E, G, and J were common in all strains. Weak bands varied slightly in mobility and in number among tobacco types. Studies of cell fractions of Burley 21 leaves yielded information that bands A, C, D, G, and J are present in the cytoplasm, whereas all but bands B, E, L, and M appeared to be identical in the chloroplast, mitochondrial, and nuclear extracts. The resemblance in protein banding pattern among the organelles indicates similarity in their membrane proteins. Bands B, E, L, and M are associated with plasma membrane or cell wall. During simulated air-curing, a majority of bands diminished by the tenth day, whereas bands B, E, and G remained highly intense and the concentration of band C was reduced in cured leaves. Bands B, E, and G reacted positively with the periodic-acid Schiff's reagent (PAS) but negatively with the colloidal ion staining. Trypsin digestion abolished protein bands stained with amido black or the PAS reagent. Results suggest that bands B, E, and G are neutral or weakly acidic glycoproteins

Acceso abierto

The Determination of Tobacco Additives1st Report: A Method for the Qualitative and Quantitative Determination of Vanillin, Ethylvanillin, Coumarin and Dihydrocoumarin in Tobacco and Tobacco Products/Zur Bestimmung von Tabakadditiven: 1. Mitteilung: Eine Methode zur qualitativen und quantitativen Bestimmung von Vanillin, Aethylvanillin, Cumarin und Dihydrocumarin in Tabak und Tabakerzeugnissen

Publicado en línea: 12 Jul 2014
Páginas: 290 - 294

Resumen

Abstract

A screening method has been developed for the qualitative and quantitative determination of vanillin, ethylvanillin, coumarin and dihydrocoumarin. The compounds are qualitatively determined by thin-layer chromatography after extraction of tobacco and purification of the extract. The quantitative determination is made by gas chromatography: Coumarin and dihydrocoumarin are determined directly and vanillin and ethylvanillin after silylation in the form of trimethylsilyl derivatives. Detection limit: thin-layer chromatography = 1 µg, gas chromatography = 0.02 µg. The coefficient of variation of the results obtained amounts to 2.4 % for vanillin and to 6.7 % for coumarin

Acceso abierto

Cigarette Smoke Formation Studies. I. Distribution and Mainstream Products From Added 14C- Dotriacontane-16,17

Publicado en línea: 12 Jul 2014
Páginas: 295 - 298

Resumen

Abstract

The distribution of 14C-dotriacontane-16,17 and its combustion and pyrolytic products in cigarette smoke is described. Twenty-one percent of the activity is found in the mainstream smoke, 49 % is found in the sidestream smoke, and 30 % is found in the butt. Of the mainstream activity, 95 % is in unchanged dotriacontane. The transfer of 14C-dotriacontane to mainstream smoke is linear throughout the smoking of the cigarette, as shown by puff-by-puff data. Hypotheses to explain the results are presented

Acceso abierto

Cigarette Smoke Formation Studies: II. Smoke Distribution and Mainstream Pyrolytic Composition of Added 14C-Menthol (U)

Publicado en línea: 12 Jul 2014
Páginas: 299 - 301

Resumen

Abstract

The distribution of 14C-menthol (U) and its combustion and pyrolytic products in cigarette smoke is described. The mainstream smoke contains 28.9 percent of the total activity with 44.3 percent in the sidestream smoke and 26.9 percent in the butt. The major 14C-menthol smoke product in the mainstream smoke is unchanged menthol (98.9%). A puff-by-puff plot of menthol delivery is presented. The results obtained are explained hypothetically

Acceso abierto

Chemical Studies on Tobacco Smoke. XIII. Inhibition of the Pyrosyntheses of Several Selective Smoke Constituents

Publicado en línea: 12 Jul 2014
Páginas: 302 - 306

Resumen

Abstract

Earlier studies demonstrated that polynuclear aromatic hydrocarbons (PAH) are selectively reduced in the smoke of alkali nitrate rich tobaccos. We hypothesized, therefore, that in the burning cone of a tobacco product, the non-volatilized organic compounds are partially pyrolyzed to C,H-radicals that may combine with each other and form, among others, the thermodynamically favoured PAH. Since we have in the burning cone of nitrate rich tobaccos an excess of thermically activated nitrogen oxides, we assumed that these may react as scavengers for C,H-radicals and, with it, partially inhibit the PAH pyrosynthesis. The present study was designed to challenge our working hypothesis. For the experiments we employed cigarettes to which we had added various amounts of KNO3 (0, 2.5, 5.0, 7.0 and 8.0 %). As expected, the yields of nitromethane, nitroethane, and nitrobenzene in the smoke increased with the increased of nitrate in the tobacco and the yields of phenanthrene, benz[a]anthracene, and benz[a]pyrene decreased. The concentration of naphthalene was only to a minor degree reduced with the increase of nitrates in the tobacco. One explanation for this observation could be that naphthalenes are primarily formed from specific tobacco terpenes, as suggested in the literature. As was expected, the smoke yields of N-unsubstituted and N-alkylated indoles was relatively little affected by the increase in the nitrate content, since these agents are predominantly formed from tryptophan. It was our objective to contribute to the understanding of the pyrosynthesis of carcinogenic PAH and the selective reduction of PAH in the smoke of nitrate rich tobacco. With the increase of our knowledge in this area we may also find an explanation for the reduced tumorigenicity of condensates from nitrate rich tobaccos

Acceso abierto

Measurement of Paper Porosity

Publicado en línea: 12 Jul 2014
Páginas: 307 - 311

Resumen

Abstract

The ''porosity'' or ''air permeability'' of cigarette tissue is measured by many different instruments, is expressed in various units and it is frequently impossible to correlate such measurements and the readings of such instruments. The property of a paper whereby it allows air and gases to pass through it while still containing the burning tobacco rod is of great and increasing interest in both the Research Laboratory and Raw Material Control Laboratory of the cigarette and filter rod manufacturer. Interest in papers of higher air permeability continues to grow, particularly in regard to the so-called ''Health Hazards of Smoking", and thus the effect of smoke dilution. Such interest by the cigarette and filter rod manufacturer necessarily means that the paper manufacturer must pay especial attention to this property during paper manufacture and in development work. He also requires to define and measure the property in his control and research laboratories. Unfortunately, there is no common language to describe this property and as interest in higher porosities grows so the shortcomings of some methods of measurement are highlighted. The situation is further complicated by the need of control laboratories for robust, simple to operate instruments, while a research laboratory might be more interested in accuracy and precision, while being less affected by the demands of careful operation and manipulation. Likely sample sizes can also vary, from small spills cut from individual cigarettes or rods, through long narrow skeins to the papermakers' sheets. A standard definition of air permeability of a sheet of paper has therefore been proposed and an instrument has been designed, using this definition, to meet the requirements of all interested parties. A number of these instruments have been built and proved by practical usage

Acceso abierto

Resolutions of the 5th tobacco colloquium 1963 regarding the nomenclature of air permeability of cigarette paper and related terms - Beschlüsse des 5. Tabak-Kolloquiums 1963 zur Nomenklatur der Luftdurchlässigkeit von Cigarettenpapier und verwandter Begriffe

Publicado en línea: 12 Jul 2014
Páginas: 312 - 314

Resumen

Abstract

1. Air permeability

1.1 Porosity

1.2 Perforation

2. Coefficient o fair permability oft he paper

3. Degree of ventilation of cigarettes

12 Artículos
Acceso abierto

Irrigation Experiments on Oriental Tobacco

Publicado en línea: 12 Jul 2014
Páginas: 259 - 261

Resumen

Abstract

Irrigation experiments were conducted at the Tobacco Institute of Drama and the Tobacco Research Station of Xanthi on aromatic and on neutral (Kaba-Koulak) tobacco. Both tobacco types benefited highly from a moderate water supply from 40-80 m3 per stremma. Yield was increased by about 20-30 % and quality was also significantly improved. Nicotine content was reduced in a proportion of 5-10 %. In the aromatic types, topping and close spacing gave significantly higher yield per stremma The nicotine level was higher with topping and lower with close spacing

Acceso abierto

''Ripening'' Tobacco with the Ethylene-Releasing Agent 2-Chloroethylphosphonic Acid

Publicado en línea: 12 Jul 2014
Páginas: 262 - 265

Resumen

Abstract

Treatment of flue-cured tobacco with the ethylene releasing agent 2-chloroethylphosphonic acid (CEPA) caused mature leaves to lose their green colour and turn yellow. The treated leaves appeared to go through a partial "yellowing'' or "colouring" phase prior to harvest. Treated leaves at harvest contained greater amounts of reducing sugars and lower levels of starch, relative to comparable untreated leaves. At the end of the curing process, comparisons between treated and untreated leaf showed that only small differences existed in total nitrogen, total alkaloids, starch, and reducing sugars. Statistically, protein of leaf treated with CEPA was significantly lower as compared to untreated leaf. For all yellowing times, dollar values per hundred weight of cured leaf from treated plants were higher than from untreated plants, but the average weight per leaf from treated plants was lower. During the curing process, leaf treated with CEPA can probably be subjected to shorter periods of yellowing or colouring than untreated leaf. If further work with "ripening'' chemicals such as CEPA show that they can be used to hasten yellowing or ripen tobacco successfully, as well as to reduce the time required for curing the crop, economic advantages are likely to accrue. It is to be hoped that such chemicals may help reduce the labour and investment required for crop production, and at the same time improve crop quality

Acceso abierto

Tobacco Chemistry. 3: Unsaturated Hydrocarbon Constituents of Greek Tobacco

Publicado en línea: 12 Jul 2014
Páginas: 266 - 274

Resumen

Abstract

Tobacco from Serres, Greece, has been studied with respect to the content of unsaturated hydrocarbons. The isolation of these constituents involved as a key step distillation with the aid of a new technique using carbon dioxide as carrier gas and total condensation of this and the distillate at liquid nitrogen temperature. In addition to the main constituent, neophytadiene, the unsaturated hydrocarbon fraction was shown to contain a series of aromatic compounds. These were examined by means of gas chromatography on capillary columns and also by gas chromatography in combination with mass spectrometry. Fractions were examined before and after elimination of smaller amounts of accompanying olefinic material with the aid of osmium tetroxide. The aromatic constituents were found to be alkylated benzene and naphthalene derivatives, of which many have been identified unambiguously. The vast majority of these have not previously been encountered in tobacco. Several have, however, been detected in smoke and the present results therefore show that these compounds are not necessarily formed solely in the pyrolysis process

Acceso abierto

Principal Aliphatic Secondary Amines of Burley Tobacco

Publicado en línea: 12 Jul 2014
Páginas: 275 - 278

Resumen

Abstract

Quantity and distribution of the principal aliphatic secondary amines - dimethylamine, methylethylamine, diethylamine, and methylpropylamine - varied within plant tissue and among Nicotiana spp. In Burley tobacco the stem tissue had the highest content of these amines and the leaf midrib the lowest. Leaf lamina, roots and seed were intermediate in amine content. Among Nicotiana spp. there was considerable difference in total amine content as well as among the ratios of the amine fractions measured. Amine content of tissue was positively correlated with nitrogen content of tissue and was altered by the drying process of tissue prior to analysis. The amines were not present as free amines or salts but were detected only following steam distillation from a basic medium

Acceso abierto

Changes of Alkaloid Composition During Curing in Three lsogenic Burley Tobaccos and Their F1 Hybrids

Publicado en línea: 12 Jul 2014
Páginas: 279 - 284

Resumen

Abstract

Quantitative changes of nicotine, nornicotine, anabasine (including anatabine), and total alkaloids in the juvenile leaves and roots of Nicotiana tabacum cv. Burley 21 (HN) and its isogenic lines selected for nicotine conversion (C), and low total alkaloids (LN) were studied during air-curing simulation. In the leaf, the C line contained less total alkaloids but more nornicotine than the HN line, suggesting that some may have been converted to nornicotine during leaf growth. The conversion phenomenon was not observed in the root. The root tissues of the LN line showed a high rate of nicotine decomposition at the inception of curing. On the basis of F1 results, both total alkaloids and nicotine conversion are governed by dominant factors. An intermediate nornicotine / nicotine ratio for the cured leaves of the LN and C hybrids indicated the presence of converter modifiers in the LN line. In the C line and its hybrids the decrease of nicotine content mainly occurred at the beginning of curing, whereas the nornicotine increase appeared after the eighth day of curing. The amount of anabasine was increased in the leaf but was decreased in the roots by curing

Acceso abierto

Electrophoretic Patterns of Soluble Proteins in Tobacco Leaf During Curing

Publicado en línea: 12 Jul 2014
Páginas: 285 - 289

Resumen

Abstract

Polyacrylamide gel disc electrophoresis revealed at least 13 anodic protein bands in leaf extracts of seven tobacco (Nicotiana tabacum L.) strains representing Burley, Turkish, flue- and fire-cured types. Four major bands B, E, G, and J were common in all strains. Weak bands varied slightly in mobility and in number among tobacco types. Studies of cell fractions of Burley 21 leaves yielded information that bands A, C, D, G, and J are present in the cytoplasm, whereas all but bands B, E, L, and M appeared to be identical in the chloroplast, mitochondrial, and nuclear extracts. The resemblance in protein banding pattern among the organelles indicates similarity in their membrane proteins. Bands B, E, L, and M are associated with plasma membrane or cell wall. During simulated air-curing, a majority of bands diminished by the tenth day, whereas bands B, E, and G remained highly intense and the concentration of band C was reduced in cured leaves. Bands B, E, and G reacted positively with the periodic-acid Schiff's reagent (PAS) but negatively with the colloidal ion staining. Trypsin digestion abolished protein bands stained with amido black or the PAS reagent. Results suggest that bands B, E, and G are neutral or weakly acidic glycoproteins

Acceso abierto

The Determination of Tobacco Additives1st Report: A Method for the Qualitative and Quantitative Determination of Vanillin, Ethylvanillin, Coumarin and Dihydrocoumarin in Tobacco and Tobacco Products/Zur Bestimmung von Tabakadditiven: 1. Mitteilung: Eine Methode zur qualitativen und quantitativen Bestimmung von Vanillin, Aethylvanillin, Cumarin und Dihydrocumarin in Tabak und Tabakerzeugnissen

Publicado en línea: 12 Jul 2014
Páginas: 290 - 294

Resumen

Abstract

A screening method has been developed for the qualitative and quantitative determination of vanillin, ethylvanillin, coumarin and dihydrocoumarin. The compounds are qualitatively determined by thin-layer chromatography after extraction of tobacco and purification of the extract. The quantitative determination is made by gas chromatography: Coumarin and dihydrocoumarin are determined directly and vanillin and ethylvanillin after silylation in the form of trimethylsilyl derivatives. Detection limit: thin-layer chromatography = 1 µg, gas chromatography = 0.02 µg. The coefficient of variation of the results obtained amounts to 2.4 % for vanillin and to 6.7 % for coumarin

Acceso abierto

Cigarette Smoke Formation Studies. I. Distribution and Mainstream Products From Added 14C- Dotriacontane-16,17

Publicado en línea: 12 Jul 2014
Páginas: 295 - 298

Resumen

Abstract

The distribution of 14C-dotriacontane-16,17 and its combustion and pyrolytic products in cigarette smoke is described. Twenty-one percent of the activity is found in the mainstream smoke, 49 % is found in the sidestream smoke, and 30 % is found in the butt. Of the mainstream activity, 95 % is in unchanged dotriacontane. The transfer of 14C-dotriacontane to mainstream smoke is linear throughout the smoking of the cigarette, as shown by puff-by-puff data. Hypotheses to explain the results are presented

Acceso abierto

Cigarette Smoke Formation Studies: II. Smoke Distribution and Mainstream Pyrolytic Composition of Added 14C-Menthol (U)

Publicado en línea: 12 Jul 2014
Páginas: 299 - 301

Resumen

Abstract

The distribution of 14C-menthol (U) and its combustion and pyrolytic products in cigarette smoke is described. The mainstream smoke contains 28.9 percent of the total activity with 44.3 percent in the sidestream smoke and 26.9 percent in the butt. The major 14C-menthol smoke product in the mainstream smoke is unchanged menthol (98.9%). A puff-by-puff plot of menthol delivery is presented. The results obtained are explained hypothetically

Acceso abierto

Chemical Studies on Tobacco Smoke. XIII. Inhibition of the Pyrosyntheses of Several Selective Smoke Constituents

Publicado en línea: 12 Jul 2014
Páginas: 302 - 306

Resumen

Abstract

Earlier studies demonstrated that polynuclear aromatic hydrocarbons (PAH) are selectively reduced in the smoke of alkali nitrate rich tobaccos. We hypothesized, therefore, that in the burning cone of a tobacco product, the non-volatilized organic compounds are partially pyrolyzed to C,H-radicals that may combine with each other and form, among others, the thermodynamically favoured PAH. Since we have in the burning cone of nitrate rich tobaccos an excess of thermically activated nitrogen oxides, we assumed that these may react as scavengers for C,H-radicals and, with it, partially inhibit the PAH pyrosynthesis. The present study was designed to challenge our working hypothesis. For the experiments we employed cigarettes to which we had added various amounts of KNO3 (0, 2.5, 5.0, 7.0 and 8.0 %). As expected, the yields of nitromethane, nitroethane, and nitrobenzene in the smoke increased with the increased of nitrate in the tobacco and the yields of phenanthrene, benz[a]anthracene, and benz[a]pyrene decreased. The concentration of naphthalene was only to a minor degree reduced with the increase of nitrates in the tobacco. One explanation for this observation could be that naphthalenes are primarily formed from specific tobacco terpenes, as suggested in the literature. As was expected, the smoke yields of N-unsubstituted and N-alkylated indoles was relatively little affected by the increase in the nitrate content, since these agents are predominantly formed from tryptophan. It was our objective to contribute to the understanding of the pyrosynthesis of carcinogenic PAH and the selective reduction of PAH in the smoke of nitrate rich tobacco. With the increase of our knowledge in this area we may also find an explanation for the reduced tumorigenicity of condensates from nitrate rich tobaccos

Acceso abierto

Measurement of Paper Porosity

Publicado en línea: 12 Jul 2014
Páginas: 307 - 311

Resumen

Abstract

The ''porosity'' or ''air permeability'' of cigarette tissue is measured by many different instruments, is expressed in various units and it is frequently impossible to correlate such measurements and the readings of such instruments. The property of a paper whereby it allows air and gases to pass through it while still containing the burning tobacco rod is of great and increasing interest in both the Research Laboratory and Raw Material Control Laboratory of the cigarette and filter rod manufacturer. Interest in papers of higher air permeability continues to grow, particularly in regard to the so-called ''Health Hazards of Smoking", and thus the effect of smoke dilution. Such interest by the cigarette and filter rod manufacturer necessarily means that the paper manufacturer must pay especial attention to this property during paper manufacture and in development work. He also requires to define and measure the property in his control and research laboratories. Unfortunately, there is no common language to describe this property and as interest in higher porosities grows so the shortcomings of some methods of measurement are highlighted. The situation is further complicated by the need of control laboratories for robust, simple to operate instruments, while a research laboratory might be more interested in accuracy and precision, while being less affected by the demands of careful operation and manipulation. Likely sample sizes can also vary, from small spills cut from individual cigarettes or rods, through long narrow skeins to the papermakers' sheets. A standard definition of air permeability of a sheet of paper has therefore been proposed and an instrument has been designed, using this definition, to meet the requirements of all interested parties. A number of these instruments have been built and proved by practical usage

Acceso abierto

Resolutions of the 5th tobacco colloquium 1963 regarding the nomenclature of air permeability of cigarette paper and related terms - Beschlüsse des 5. Tabak-Kolloquiums 1963 zur Nomenklatur der Luftdurchlässigkeit von Cigarettenpapier und verwandter Begriffe

Publicado en línea: 12 Jul 2014
Páginas: 312 - 314

Resumen

Abstract

1. Air permeability

1.1 Porosity

1.2 Perforation

2. Coefficient o fair permability oft he paper

3. Degree of ventilation of cigarettes

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