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Informacje o czasopiśmie
Format
Czasopismo
eISSN
2719-9509
Pierwsze wydanie
01 Jan 1992
Częstotliwość wydawania
4 razy w roku
Języki
Angielski

Wyszukiwanie

Tom 8 (1975): Zeszyt 4 (December 1975)

Informacje o czasopiśmie
Format
Czasopismo
eISSN
2719-9509
Pierwsze wydanie
01 Jan 1992
Częstotliwość wydawania
4 razy w roku
Języki
Angielski

Wyszukiwanie

12 Artykułów
Otwarty dostęp

Leaf Quality and Usability: Theoretical Model I

Data publikacji: 14 Aug 2014
Zakres stron: 167 - 173

Abstrakt

Abstract

A changing concept in recent years on the usability of tobacco leaf has introduced many problems that may, not fit the traditional requirements of leaf quality. Usability represents the state of being usable without adverse effects to consumers. Theoretical Model I with selected markers is proposed for the development of tobacco materials with emphasis on improving tobacco usability. This preliminary Model I is based on currently available data, and can be improved as new information becomes available. Plant scientists may use this model to develop leaf tobacco of improved usability either through breeding, selection, and culture, or by means of homogenized leaf curing and reconstitution

Otwarty dostęp

The Thermal Degradation of Tobacco: VI. Influence of Extraction on the Formation of Some Major Gas Phase Constituents

Data publikacji: 14 Aug 2014
Zakres stron: 174 - 180

Abstrakt

Abstract

Formation profiles have been determined for the major gas phase constituents formed in an inert atmosphere during the dynamic thermal decomposition of tobaccos extracted with hexane, chloroform, acetone, acetonitrile, and methanol. The profiles include methane, ethane, ethene, propane, propene, isoprene, formaldehyde, acetaldehyde, acetone, 2-butanone, acetonitrile, benzene, and toluene. Except for propene and propane, extraction of tobacco does not dramatically influence either the temperatures for maximum formation or the level of hydrocarbons formed during thermal decomposition of the tobaccos. This suggests that the majority of the gas phase hydrocarbons are formed from the insoluble leaf constituents. Isoprene has formation maxima at 375°C and 450°C, and extraction of tobacco with non-polar solvents removes leaf precursors responsible for the formation maxima at 375°C. Polar solvents remove the major isoprene precursors which are responsible for the maxima at 375° and 450°C. Extraction effects an increase of both formaldehyde and acetaldehyde formation but has little influence on the formation of either acetone or 2-butanone. The formation profile for acetonitrile has been established and shows that it has maximum formation at 410° and 500°C. Extraction has no influence either on the formation of benzene or toluene. Data from the profiles of these volatile constituents generally agree with smoke data from extracted tobacco which indicates that this method is useful for studying factors that influence the formation of the gas phase constituents

Otwarty dostęp

Determination of Ethylene and lsoprene in the Gas Phase of Cigarette Smoke by Infra-red Spectroscopy

Data publikacji: 14 Aug 2014
Zakres stron: 181 - 185

Abstrakt

Abstract

An infra-red method was developed for the quantitative determination of ethylene and isoprene in the gas phase of cigarette smoke. The smoke was collected by smoking the cigarettes on a five-port syringe type smoking machine and transferring it to a gas cell positioned in a double-beam infra-red spectrophotometer for the duration of the analysis. The smoke transfer to the gas cell and its subsequent removal from the celI were accomplished by connecting the smoking machine to a vacuum pump through the automated solenoid valve unit which controlled the analysis system. In this manner any specific puff of interest could be analysed for the ethylene and isoprene concentrations by measuring the corrected absorbance of the 10.52 µm and 11.18 µm absorbance bands, respectively. TotaI deliveries of ethylene and isoprene per cigarette were obtained by adding the deliveries from the individual puffs. The puff-by-puff delivery profile also was obtainable at the same time. In addition filter efficiency for ethylene and isoprene removaI may be determined by this method. The relative standard deviation at the two-sigma level was 3 % for ethylene and isoprene in the gas phase smoke from commercial cellulose acetate filter cigarettes. The analysis of a particular puff of smoke required only 75 seconds insuring the analysis of a relatively fresh smoke with good reproducibility and accuracy.

Otwarty dostęp

The Reducing Property of Tobacco Smoke: 1. Modified FIue-Cured Tobacco and Other Smoking Products

Data publikacji: 14 Aug 2014
Zakres stron: 186 - 192

Abstrakt

Abstract

In order to determine which tobacco constituents give rise to reducing compounds in smoke as well as to find out what factors affected the reducing property of the latter, modifications of flue-cured tobacco by solvent extraction and chemical impregnations were carried out. While no unequivocal evidence has been obtained as to the main source of reducing activity, all the evidence suggests that lignin and phenolic compounds derived therefrom, are the main contributors to reducing activity. A number of cigarette parameters, strand width, expansion of tobacco, paper porosity and burn control additives were studied and found to have no significant effect, within the Iimits tested, on the reducing power of the smoke. On the other hand, additives such as glycerol, ethylene glycol, polyethylene glycol, polypropylene glycol and carbowax gave distinctly lower reducing activities. Examination of tobacco products showed Iower reducing activities in smoke from Cuban, Latakia and Turkish tobaccos, as well as in smoke from cigarettes made from Indian sun-cured and French dark, fermented tobaccos. The lowest reducing activity was recorded for the highly fermented Perique tobacco. Indian ''bidis'' have specific reducing activities similar to those of standard flue-cured cigarettes. Freshly harvested, rapidly dried green tobacco as well as dried beech leaves, gave specific reducing activities close to those obtained for regular cigarettes. On the other hand, commercially available lettuce cigarettes, which undergo a fermentation step in their manufacture, gave distinctly lower specific activity

Otwarty dostęp

The Reducing Property of Tobacco Smoke: 2. The Influence of Smoking Vehicle, with Particular Reference to the Pipe

Data publikacji: 14 Aug 2014
Zakres stron: 193 - 198

Abstrakt

Abstract

A detailed investigation of pipe smoking was undertaken to elucidate why this mode of smoking produced condensates of low dichlorophenolindophenol (DCIP)-reducing activity. Pipe tobaccos, smoked in cigarette tubes, gave reducing activities distinctly lower than those obtained for flue-cured tobacco, but the values were still higher than those obtained in pipe smoking. In pipe smoking, using both flue- and air-cured tobaccos, the initial high specific reducing activities (during 5-10 minutes of smoking) dropped to very Iow values towards the end of smoking. The decreasing specific activities paralleled the formation of water. No reducing activity was trapped by the water accumulating in the pipe, but a considerable amount of activity was trapped by the unsmoked tobacco. Unlike cigarette and cigarillo smoking, the trapped activity in cigar and pipe smoking was sufficient to significantly alter specific activity, but stilI much too Iow to obtain, in cigar and pipe smoking, the large totaI activities obtained in cigarette and cigarillo smoking. In the other three modes of smoking, viz cigarette, cigarillo and cigar, there was no change in specific activity with increase in duration of smoking (or change in butt length).

Otwarty dostęp

Material Balance Studies on Cigarettes Containing 3-Phenyl-5-methyl-1,2,4oxadiazole

Data publikacji: 14 Aug 2014
Zakres stron: 199 - 203

Abstrakt

Abstract

Material balance studies were performed on 85 mm machine-made cigarettes containing 1.5 % unlabelled PMO [3-phenyl-5-methyl-1,2,4-oxadiazole], which were smoked under standard conditions to a 23 mm butt length. Using standard analytical techniques, relative distributions of PMO of approximately 28 % for mainstream, 22 % for sidestream, and 27 % for butt were obtained, with an overall recovery of unchanged PMO of 75-80 %. Radiocarbon labeled PMO [5-14C] cigarettes were prepared manually (70 mm, 2 % PMO) and smoked under standard conditions to a 20 mm butt length. Four smoking runs gave statistically valid data accounting for 95.99 ± 0.58 % of the original label. Measurements of the radioactivity were made by liquid scintillation counting of the various fractions. The mainstream smoke passing through a Cambridge filter pad contained less than one percent of the label as carbon dioxide, and no volatile organic compounds. The PMO undergoing decomposition gave rise to products found almost entirely in the sidestream.

Otwarty dostęp

Chromatographic Determination of Hydrocarbon Waxes in Tobacco Leaf and Smoke

Data publikacji: 14 Aug 2014
Zakres stron: 204 - 210

Abstrakt

Abstract

Paraffins of tobacco Ieaf were separated by column chromatography on silicic acid. Leaf paraffins were fractionated from other wax constituents by chromatography in a definite sample to substrate to solvent ratio. The developed method was used to evaluate the transfer of paraffins and neophytadiene from leaf to smoke in a reference cigarette. Gas chromatographic separations were performed on a high-temperature liquid phase. Gas chromatography in conjunction with mass spectrometry was used to determine the paraffin composition of a representative flue-cured tobacco, a reference cigarette tobacco, and smoke condensate. It was concluded that paraffins were probably transferred to smoke relatively unchanged, while neophytadiene underwent some pyrolytic decomposition.

Otwarty dostęp

Phytosterols in Tobacco: Quantitative Analysis and Fate in Tobacco Combustion

Data publikacji: 14 Aug 2014
Zakres stron: 211 - 218

Abstrakt

Abstract

The influence of tobacco phytosterols (cholesterol, campesterol, stigmasteroI, b-sitosterol) on the chemical composition and biologicaI activity of tobacco smoke has been of concern to tobacco chemists. Therefore, a relatively simple method, utilizing a 14C-internal standard, chromatography on Sephadex and gas-liquid chromatography, was developed for the quantitative analysis of the phytosterols; this method was applied to the tobacco and smoke (mainstream and sidestream) of cigarettes and cigars to determine the fate of the phytosterols in burning tobacco. About 20 % of the total phytosterol content of tobacco was shown to be transferred intact into the smoke; about 2 % was possibly converted into polynuclear aromatic hydrocarbons. Radioactive tracer and pyrolysis studies were used to determine the nature of the phytosterol degradation products found in the smoke.

Otwarty dostęp

One-Dimensional Gas Concentration Profiles Within a Burning Cigarette During a Puff

Data publikacji: 14 Aug 2014
Zakres stron: 219 - 224

Abstrakt

Abstract

A technique for axial concentration measurements of several gas phase components of cigarette smoke during a two-second puff has been described. Gas concentration profiles constructed from these measurements were used to determine the axial order of the reactions which determine these concentrations. A one-dimensional model combustion reaction profile and a one-dimensional model coal temperature profile were presented. The diffusivities of several combustion gases through cigarette paper were calculated from the concentration data using the Owens-Reynolds model for the isothermal diffusion of gases through cigarette paper.

Otwarty dostęp

Formation of the Porous Structure of Cigarette Filters

Data publikacji: 14 Aug 2014
Zakres stron: 225 - 232

Abstrakt

Abstract

An originaI method based on permeability measurement is applied to studying the formation of the porous interstitial structure of cigarette filters. Using this method, it is shown that the porous structure of a filter is formed in the course of the filling process which is accomplished by compression of the filter material without significantly modifying the specific structure of this material. In the filling process, the elements of the filter material are assembled in the filter by imbrication. A given filter materiaI is characterised by the specific volume that it takes up when its elements are assembled at the compression Iimit without any crushing. A filter material is, moreover, characterised by the mode of assembling of its elements in the formation of the porous interstitial structure of a filter. The permeametric method allows us to define this characteristic. The results can be applied to the choice of filter material and to the determination of the optimum filling rate permitting the rapid development of a cigarette filter with fixed characteristics.

Otwarty dostęp

Genetic Influence on Chemical Constituents of Tobacco Leaf and Smoke

Data publikacji: 14 Aug 2014
Zakres stron: 233 - 240

Abstrakt

Abstract

Investigations have shown that many chemical constituents in tobacco (Nicotiana tabacum L.) plants and in the cured leaf are influenced by genetic, environmental, and cultural factors. The genetic basis for nicotine synthesis is well documented and plant breeders are capable of developing cultivars with varying levels. Differences for chemical constituents have been detected among cultivars and breeding lines which are attributed to genetic factors. Some of these constituents are: reducing sugars, polyphenols, phytosterols, and nitrogenous compounds. Research also indicates that alkalinity of water-soluble ash and certain smoke constituents are influenced by genetic factors

Otwarty dostęp

Residue Levels of Fatty Compounds and Surfactants as Suckering Agents on Tobacco

Data publikacji: 14 Aug 2014
Zakres stron: 241 - 245

Abstrakt

Abstract

Fatty compounds including lauryI alcohol and methyl laurate and Tween 20 surfactant (polyoxyethylene [20] sorbitan monolaurate) and Tween 80 surfactant (polyoxyethylene [20] sorbitan monooleate) with 14C-labelling at various positions were used as suckering agents for Maryland, Burley, and bright tobacco types (Nicotiana tabacum L.) and their residues on the tobacco determined. An average residue of 1.61 ppm of fatty compounds and 1.0 ppm of surfactants were found. The combined totaI of 2.6 ppm residue due to these suckering agents is far below an earlier preliminary test of 4.8 ppm of residue in comparison with 7.000 ppm naturally occurring fatty compounds in tobacco.

12 Artykułów
Otwarty dostęp

Leaf Quality and Usability: Theoretical Model I

Data publikacji: 14 Aug 2014
Zakres stron: 167 - 173

Abstrakt

Abstract

A changing concept in recent years on the usability of tobacco leaf has introduced many problems that may, not fit the traditional requirements of leaf quality. Usability represents the state of being usable without adverse effects to consumers. Theoretical Model I with selected markers is proposed for the development of tobacco materials with emphasis on improving tobacco usability. This preliminary Model I is based on currently available data, and can be improved as new information becomes available. Plant scientists may use this model to develop leaf tobacco of improved usability either through breeding, selection, and culture, or by means of homogenized leaf curing and reconstitution

Otwarty dostęp

The Thermal Degradation of Tobacco: VI. Influence of Extraction on the Formation of Some Major Gas Phase Constituents

Data publikacji: 14 Aug 2014
Zakres stron: 174 - 180

Abstrakt

Abstract

Formation profiles have been determined for the major gas phase constituents formed in an inert atmosphere during the dynamic thermal decomposition of tobaccos extracted with hexane, chloroform, acetone, acetonitrile, and methanol. The profiles include methane, ethane, ethene, propane, propene, isoprene, formaldehyde, acetaldehyde, acetone, 2-butanone, acetonitrile, benzene, and toluene. Except for propene and propane, extraction of tobacco does not dramatically influence either the temperatures for maximum formation or the level of hydrocarbons formed during thermal decomposition of the tobaccos. This suggests that the majority of the gas phase hydrocarbons are formed from the insoluble leaf constituents. Isoprene has formation maxima at 375°C and 450°C, and extraction of tobacco with non-polar solvents removes leaf precursors responsible for the formation maxima at 375°C. Polar solvents remove the major isoprene precursors which are responsible for the maxima at 375° and 450°C. Extraction effects an increase of both formaldehyde and acetaldehyde formation but has little influence on the formation of either acetone or 2-butanone. The formation profile for acetonitrile has been established and shows that it has maximum formation at 410° and 500°C. Extraction has no influence either on the formation of benzene or toluene. Data from the profiles of these volatile constituents generally agree with smoke data from extracted tobacco which indicates that this method is useful for studying factors that influence the formation of the gas phase constituents

Otwarty dostęp

Determination of Ethylene and lsoprene in the Gas Phase of Cigarette Smoke by Infra-red Spectroscopy

Data publikacji: 14 Aug 2014
Zakres stron: 181 - 185

Abstrakt

Abstract

An infra-red method was developed for the quantitative determination of ethylene and isoprene in the gas phase of cigarette smoke. The smoke was collected by smoking the cigarettes on a five-port syringe type smoking machine and transferring it to a gas cell positioned in a double-beam infra-red spectrophotometer for the duration of the analysis. The smoke transfer to the gas cell and its subsequent removal from the celI were accomplished by connecting the smoking machine to a vacuum pump through the automated solenoid valve unit which controlled the analysis system. In this manner any specific puff of interest could be analysed for the ethylene and isoprene concentrations by measuring the corrected absorbance of the 10.52 µm and 11.18 µm absorbance bands, respectively. TotaI deliveries of ethylene and isoprene per cigarette were obtained by adding the deliveries from the individual puffs. The puff-by-puff delivery profile also was obtainable at the same time. In addition filter efficiency for ethylene and isoprene removaI may be determined by this method. The relative standard deviation at the two-sigma level was 3 % for ethylene and isoprene in the gas phase smoke from commercial cellulose acetate filter cigarettes. The analysis of a particular puff of smoke required only 75 seconds insuring the analysis of a relatively fresh smoke with good reproducibility and accuracy.

Otwarty dostęp

The Reducing Property of Tobacco Smoke: 1. Modified FIue-Cured Tobacco and Other Smoking Products

Data publikacji: 14 Aug 2014
Zakres stron: 186 - 192

Abstrakt

Abstract

In order to determine which tobacco constituents give rise to reducing compounds in smoke as well as to find out what factors affected the reducing property of the latter, modifications of flue-cured tobacco by solvent extraction and chemical impregnations were carried out. While no unequivocal evidence has been obtained as to the main source of reducing activity, all the evidence suggests that lignin and phenolic compounds derived therefrom, are the main contributors to reducing activity. A number of cigarette parameters, strand width, expansion of tobacco, paper porosity and burn control additives were studied and found to have no significant effect, within the Iimits tested, on the reducing power of the smoke. On the other hand, additives such as glycerol, ethylene glycol, polyethylene glycol, polypropylene glycol and carbowax gave distinctly lower reducing activities. Examination of tobacco products showed Iower reducing activities in smoke from Cuban, Latakia and Turkish tobaccos, as well as in smoke from cigarettes made from Indian sun-cured and French dark, fermented tobaccos. The lowest reducing activity was recorded for the highly fermented Perique tobacco. Indian ''bidis'' have specific reducing activities similar to those of standard flue-cured cigarettes. Freshly harvested, rapidly dried green tobacco as well as dried beech leaves, gave specific reducing activities close to those obtained for regular cigarettes. On the other hand, commercially available lettuce cigarettes, which undergo a fermentation step in their manufacture, gave distinctly lower specific activity

Otwarty dostęp

The Reducing Property of Tobacco Smoke: 2. The Influence of Smoking Vehicle, with Particular Reference to the Pipe

Data publikacji: 14 Aug 2014
Zakres stron: 193 - 198

Abstrakt

Abstract

A detailed investigation of pipe smoking was undertaken to elucidate why this mode of smoking produced condensates of low dichlorophenolindophenol (DCIP)-reducing activity. Pipe tobaccos, smoked in cigarette tubes, gave reducing activities distinctly lower than those obtained for flue-cured tobacco, but the values were still higher than those obtained in pipe smoking. In pipe smoking, using both flue- and air-cured tobaccos, the initial high specific reducing activities (during 5-10 minutes of smoking) dropped to very Iow values towards the end of smoking. The decreasing specific activities paralleled the formation of water. No reducing activity was trapped by the water accumulating in the pipe, but a considerable amount of activity was trapped by the unsmoked tobacco. Unlike cigarette and cigarillo smoking, the trapped activity in cigar and pipe smoking was sufficient to significantly alter specific activity, but stilI much too Iow to obtain, in cigar and pipe smoking, the large totaI activities obtained in cigarette and cigarillo smoking. In the other three modes of smoking, viz cigarette, cigarillo and cigar, there was no change in specific activity with increase in duration of smoking (or change in butt length).

Otwarty dostęp

Material Balance Studies on Cigarettes Containing 3-Phenyl-5-methyl-1,2,4oxadiazole

Data publikacji: 14 Aug 2014
Zakres stron: 199 - 203

Abstrakt

Abstract

Material balance studies were performed on 85 mm machine-made cigarettes containing 1.5 % unlabelled PMO [3-phenyl-5-methyl-1,2,4-oxadiazole], which were smoked under standard conditions to a 23 mm butt length. Using standard analytical techniques, relative distributions of PMO of approximately 28 % for mainstream, 22 % for sidestream, and 27 % for butt were obtained, with an overall recovery of unchanged PMO of 75-80 %. Radiocarbon labeled PMO [5-14C] cigarettes were prepared manually (70 mm, 2 % PMO) and smoked under standard conditions to a 20 mm butt length. Four smoking runs gave statistically valid data accounting for 95.99 ± 0.58 % of the original label. Measurements of the radioactivity were made by liquid scintillation counting of the various fractions. The mainstream smoke passing through a Cambridge filter pad contained less than one percent of the label as carbon dioxide, and no volatile organic compounds. The PMO undergoing decomposition gave rise to products found almost entirely in the sidestream.

Otwarty dostęp

Chromatographic Determination of Hydrocarbon Waxes in Tobacco Leaf and Smoke

Data publikacji: 14 Aug 2014
Zakres stron: 204 - 210

Abstrakt

Abstract

Paraffins of tobacco Ieaf were separated by column chromatography on silicic acid. Leaf paraffins were fractionated from other wax constituents by chromatography in a definite sample to substrate to solvent ratio. The developed method was used to evaluate the transfer of paraffins and neophytadiene from leaf to smoke in a reference cigarette. Gas chromatographic separations were performed on a high-temperature liquid phase. Gas chromatography in conjunction with mass spectrometry was used to determine the paraffin composition of a representative flue-cured tobacco, a reference cigarette tobacco, and smoke condensate. It was concluded that paraffins were probably transferred to smoke relatively unchanged, while neophytadiene underwent some pyrolytic decomposition.

Otwarty dostęp

Phytosterols in Tobacco: Quantitative Analysis and Fate in Tobacco Combustion

Data publikacji: 14 Aug 2014
Zakres stron: 211 - 218

Abstrakt

Abstract

The influence of tobacco phytosterols (cholesterol, campesterol, stigmasteroI, b-sitosterol) on the chemical composition and biologicaI activity of tobacco smoke has been of concern to tobacco chemists. Therefore, a relatively simple method, utilizing a 14C-internal standard, chromatography on Sephadex and gas-liquid chromatography, was developed for the quantitative analysis of the phytosterols; this method was applied to the tobacco and smoke (mainstream and sidestream) of cigarettes and cigars to determine the fate of the phytosterols in burning tobacco. About 20 % of the total phytosterol content of tobacco was shown to be transferred intact into the smoke; about 2 % was possibly converted into polynuclear aromatic hydrocarbons. Radioactive tracer and pyrolysis studies were used to determine the nature of the phytosterol degradation products found in the smoke.

Otwarty dostęp

One-Dimensional Gas Concentration Profiles Within a Burning Cigarette During a Puff

Data publikacji: 14 Aug 2014
Zakres stron: 219 - 224

Abstrakt

Abstract

A technique for axial concentration measurements of several gas phase components of cigarette smoke during a two-second puff has been described. Gas concentration profiles constructed from these measurements were used to determine the axial order of the reactions which determine these concentrations. A one-dimensional model combustion reaction profile and a one-dimensional model coal temperature profile were presented. The diffusivities of several combustion gases through cigarette paper were calculated from the concentration data using the Owens-Reynolds model for the isothermal diffusion of gases through cigarette paper.

Otwarty dostęp

Formation of the Porous Structure of Cigarette Filters

Data publikacji: 14 Aug 2014
Zakres stron: 225 - 232

Abstrakt

Abstract

An originaI method based on permeability measurement is applied to studying the formation of the porous interstitial structure of cigarette filters. Using this method, it is shown that the porous structure of a filter is formed in the course of the filling process which is accomplished by compression of the filter material without significantly modifying the specific structure of this material. In the filling process, the elements of the filter material are assembled in the filter by imbrication. A given filter materiaI is characterised by the specific volume that it takes up when its elements are assembled at the compression Iimit without any crushing. A filter material is, moreover, characterised by the mode of assembling of its elements in the formation of the porous interstitial structure of a filter. The permeametric method allows us to define this characteristic. The results can be applied to the choice of filter material and to the determination of the optimum filling rate permitting the rapid development of a cigarette filter with fixed characteristics.

Otwarty dostęp

Genetic Influence on Chemical Constituents of Tobacco Leaf and Smoke

Data publikacji: 14 Aug 2014
Zakres stron: 233 - 240

Abstrakt

Abstract

Investigations have shown that many chemical constituents in tobacco (Nicotiana tabacum L.) plants and in the cured leaf are influenced by genetic, environmental, and cultural factors. The genetic basis for nicotine synthesis is well documented and plant breeders are capable of developing cultivars with varying levels. Differences for chemical constituents have been detected among cultivars and breeding lines which are attributed to genetic factors. Some of these constituents are: reducing sugars, polyphenols, phytosterols, and nitrogenous compounds. Research also indicates that alkalinity of water-soluble ash and certain smoke constituents are influenced by genetic factors

Otwarty dostęp

Residue Levels of Fatty Compounds and Surfactants as Suckering Agents on Tobacco

Data publikacji: 14 Aug 2014
Zakres stron: 241 - 245

Abstrakt

Abstract

Fatty compounds including lauryI alcohol and methyl laurate and Tween 20 surfactant (polyoxyethylene [20] sorbitan monolaurate) and Tween 80 surfactant (polyoxyethylene [20] sorbitan monooleate) with 14C-labelling at various positions were used as suckering agents for Maryland, Burley, and bright tobacco types (Nicotiana tabacum L.) and their residues on the tobacco determined. An average residue of 1.61 ppm of fatty compounds and 1.0 ppm of surfactants were found. The combined totaI of 2.6 ppm residue due to these suckering agents is far below an earlier preliminary test of 4.8 ppm of residue in comparison with 7.000 ppm naturally occurring fatty compounds in tobacco.

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