bluuebunny/crossref_metadata_2025_split huggingface dataset:
A Model Study on the Diffusion and the Dilution of Low Molecular Weight Gaseous Components through Cigarette Paper during Smoking
Authors: Muramatsu M. , Mikami T. , Naito N. , Tomita H. 
Published: July 2016

AbstractThe effects of diffusion and dilution on the concentration of gaseous components have been studied by a model consisting of unlit cigarettes differing in paper porosity and length, and a standard gas mixture. Results are as follows: The difference in the concentration of gaseous components between the front and butt end of the cigarette during the puff increases with cigarette length and paper porosity, and also depends on the diffusion coefficient of respective components through the cigarette paper. These changes could be explained mainly by the diffusion loss through the paper in the case of the cigarette with ordinary paper, but by both dilution with air through the paper and diffusion loss in the case of the cigarette with perforated paper. Subsequently, the levels of gaseous components such as carbon monoxide in the exit stream become lower in the Iatter cigarette. In addition, the following equation, which can fully account for these changes, has been derived:where C1i and C0i are the concentrations of the component i at the front and butt end, respectively, L the cigarette length, r the cigarette radius, s the thickness of paper, U0 and U1 the apparent linear gas velocities at the butt and front end, respectively, and Di the diffusion coefficient of component i through the paper.
The Permeability of Cigarette Papers and Cigarette Ventilation
Authors: Selke W. A. , Mathews J. H. 
Published: July 2016

AbstractThe importance of determining not only the nominal permeability of papers, but also the nature of the flow resistance was confirmed, for cigarette wrapper and for papers used in constructing ventilated filters. For perforated papers, for which the flow is not proportional to pressure drop, it was shown that logarithmic plotting and the use of the form V = k (D P)
Isolation and ldentification of 2,6- Dimethyl- and 2,2,6 -Trimethyl-4-piperidone, Artifacts Produced by the Reaction of Cigarette Smoke Condensate and Acetone
Authors: Einolf W. N. , Ferguson R. N. , Whidby J. F. , DeBardeleben J. F. 
Published: July 2016

AbstractCigarette smoke condensate (CSC) processed with acetone was found to contain 2,2,6-trimethyl-4-piperidone and the cis and trans isomers of 2,6-dimethyl-4-piperidone. The compounds were found to be artifacts formed by the reaction of the smoke components ammonia and acetaldehyde with the solvent acetone. Conditions which affected the yield of the artifacts from the processed CSC include pH, temperature, reaction time, and levels of ammonia and acetaldehyde present in CSC.
Rapid Spectrophotometric Analysis of the Chemical Composition of Tobacco: Part 2: TotaI AIkaloids
Authors: Hamid A. , McClure W.F. , Weeks W.W. 
Published: July 2016

Abstract
This paper illustrates the potential of a computerized spectrophotometer for measuring total alkaloids in tobacco. Prediction equations were developed for three optical parameters. Of the three parameters investigated d2 (log (1/R)) /d/2 gave the best results and d R / R d l gave better results than log (1/R), where reflectance R is the ratio of the detector signal of the sample to the detector signal of the ceramic standard in the reflectance mode. The coefficient of determination r2 for the prediction equation containing d2 (log (1/R)) /d/2 terms at 10 different wavelengths was 0.975. This equation predicted the total alkaloids in an independent set of samples with a standard error of 0.438 %. Instrument noise contributed 43 % of the variation, the remainder was attributed to anomalies of the chemical methods.
High-Energy Electron-Beam Processing of Tobacco
Authors: Casey W.J. , Bhatt S.A. , Suhy W.M. , Fiore J.V. 
Published: July 2016

Abstract
While it is known that ionizing radiation can bring about chemical, biological and physical changes in organic tissue, relatively little is known concerning radiation effects on tobacco and its combustion products. In an effort to study such changes, Virginia bright tobacco was exposed to ionizing radiation at doses up to 50 Mrads, generated electronically by a high-voltage discharge. It was found that tobacco exposed to this high radiation will undergo physical changes such as a darkening, an increase in brittleness, puffing of the stems and a change in aroma characteristics. Chemical changes were found in selected chemicaI components such as water and solvent solubles, nicotine, reducing sugars, dextrin, cellulose, pectin, tannins and lignin. Both physical and chemical changes seem to be dose dependent. Studies on smoke components from cigarettes of both irradiated and non-irradiated tobacco indicate that irradiation had no major effects on the components of the gas phase examined and only minor effects on the composition of the particulate phase.
A Unified Smoking-Automated Calorimetric System for the Analysis of the Gas Phase of Cigarette Smoke and its Application to the Determination of Hydrogen Sulfide
Authors: Collins P. F. , Williams J. F. 
Published: July 2016

Abstract
A system has been developed wherein the gas phase produced on smoking a cigarette through a Cambridge pad is analysed, on a puff-by-puff basis, for a desired component using automated colourimetry. The system consists of an AutoAnalyser I and a simple, 1-port smoking machine. The continuous gas stream from the smoking machine, either gas phase or intervening air, is passed concurrently with a stream of absorbing solution through a glass coil. Following passage through the coil, the solution is separated from the gas stream and introduced into the AutoAnalyser for continuous measurement of the concentration of the absorbed component. The entire system is calibrated using standard gas mixtures puffed in the same manner as the cigarette. The puff profile is essentially rectangular. Chief benefits expected from use of this system include the ability to obtain puff-by-puff measurements, a minimum time for reaction to occur in the gas phase and essentially no sample handling other than smoking the cigarette. The system has been utilized for the determination of hydrogen sulfide in gas phase using 0.1 N NaOH as the absorbing solution and the "methylene blue" colourimetric reaction. Results obtained on a variety of commercial U.S. brands ranged from 18 to 50 µg of H2S per cigarette, similar to results reported by other investigators using wet chemical methods. The accuracy of the results is supported by recovery tests wherein gaseous H2S added to the gas phase is completely recovered. The average relative standard deviations obtained with 11 U.S. commercial or reference cigarette samples using random selection of the cigarettes is 10.8 % for µg of H2S per cigarette and 8.8 % for µg of H2S per puff for a single cigarette. The basic system is thought to be applicable to the determination of a number of other components in gas phase.
Some Factors Influencing Tobacco Leaf Senescence
Authors: DeJong Donald W. , Woodlief William G. 
Published: July 2016

Abstract
Tobacco leaf disks were subjected to various types of lighting and chemical solutions to determine the interaction of these factors in leaf senescence. Far-red light promoted senescence more than light of lower wave-lengths. Magnesium at 50 mM was a potent inhibitor of senescence, whereas EDTA-disodium salt at 50 mM promoted senescence in the light but retarded senescence in the dark. Additional work with the effect of ethylene on detached leaves demonstrated that hydrolytic enzyme activity for amylase, peptidase and protease increased as a result of treatment but esterase activity decreased. The response differed with regard to variety and leaf maturity. Exposure to ethylene increased chlorogenic acid oxidase in lower leaves of pale yellow tobacco but decreased the enzyme in NC-95 lower leaves. These data relate to the growth behaviour of the two genotypes in that physiological maturity occurs at considerably different rates in pale yellow and NC-95 plants. The results help to explain why leaves of pale yellow plants tend to ripen within a much shorter time than leaves of conventional green tobacco cultivars.
Pyrolytic Evaluation of Close-Grown Tobaccos
Authors: Higman H. C. , Severson R. F. , Chortyk O. T. , Arrendale R. F. 
Published: July 2016

Abstract
A pyrolytic method for evaluating the smoke properties of tobacco materials for their potential to produce biologically significant smoke phenols and PAH has been applied to close-grown tobacco, in comparison to conventionally grown tobacco. Analyses were performed on the lipids of tobacco samples to attempt correlations with amounts of polynuclear aromatic hydrocarbons in pyrolyzates. Relative to a standard flue-cured tobacco, the close-grown tobacco samples contained lower nicotine, neophytadiene and hydrocarbon levels, and lower sterols, solanesol and fatty acid levels. Close-grown tobacco pyrolyzates contained equivalent PAH levels and higher levels of phenols. Based on the pyrolysis data, the close-grown tobaccos do not offer a more desirable smoking product than conventionally grown flue-cured tobaccos. However, the lower levels of nicotine and higher amounts of smoke phenols may possibly make the close-grown materials suitable for inclusion into low-nicotine tobacco sheet products.
The Determination of Nitric Oxide in Gas Phase Cigarette Smoke by Non-dispersive Infrared Analysis
Authors: Williams T. B. 
Published: July 2016

AbstractNitric oxide in cigarette smoke was conveniently determined by non-dispersive infrared analysis (NDIR). Recoveries of 95 % were obtained with standard gas-air mixtures but recoveries from smoke increased from 87% for high-yield to 91 % for low-yield cigarettes. Relative error was about 4 %. A reduction in the dead volume of Cambridge filter cassettes, to reduce the amount of NO reacted between puffs, increased NO deliveries of cigarettes by 4%. Deliveries of NO were estimated to average 4 % lower due to oxidation, but reaction with other smoke components reduced them further depending upon concentrations. The NO deliveries of cigarettes increased as blend nitrate increased and as the flow of air around cigarettes decreased. Nitric oxide in smoke and in standard gas-air mixtures, determined by non-dispersive infrared (NDIR) spectroscopy, was substantiated by an automated colorimetric analysis. Interfering smoke species were determined and circumvented in both methods.
A Convenient Method for the Determination of Ambient Nicotine
Authors: Crouse W. E. , Johnson L. F. , Marmor R. S. 
Published: July 2016

AbstractThe impinger tube/gas chromatograph sampling technique has distinct advantages in specificity, simplicity and accuracy over the older literature methods for airborne nicotine sampling and analysis. The impinger/GC method was found to be useful in determining nicotine concentrations in both low and high nicotine environments.
The Generation of Water in the Tobacco Oven Volatile Test
Authors: Bourlas M. C. , Magin D. F. , Kornfeld R. A. 
Published: July 2016

AbstractAn investigation into the standard oven volatile procedure has been completed. Results have been presented which support the conclusion that ≈ 0.5 % (tobacco dry weight basis) of the oven volatiles are generated via decomposition of tobacco constituents. The use of oxygen-18 labelled water for equilibrating tobacco has provided the probe necessary to differentiate between equilibrium moisture and water generated during the oven volatile test. Mass spectrometry was utilized to detect isotopically labelled tobacco constituents. Observations that 34 % of the acetic acid and a significant portion (> 50 %) of the reducing sugars exhibit oxygen-18 incorporation indicate the dynamic and interactive nature of the tobacco/ water system.
Automated Method for Simultaneous Gas-chromatographic Analysis of Nicotine and Water in the Condensate of Tobacco Smoke/Automatisierte gaschromatographische Simultanbestimmung von Nicotin und Wasser im Tabakrauchkondensat
Authors: Hollweg J. , Schumacher H.J. , Seehofer F. 
Published: July 2016

AbstractA rapid, automated method for the simultaneous quantitative analysis of nicotine and water in the condensate of tobacco smoke was developed. With the process, it is also possible to quantify the propylene glycol and diethylene glycol, as well as the triacetin contents of the condensate. The apparatus comprises an isotherm gas chromatograph with an automatic injector. A variable split is connected to the injector block, which distributes the sample between two separation columns, as analysis of all substances in a single column does not succeed in a short time. The signals of the two detectors used (thermal conductivity detector and flame ionisation detector) are transferred one after another, time-switched, to an electronic single-channel integrator to be evaluated. With the system described, up to sixty analyses a day are made possible.
Kinetics of Oxidation of Tobacco Char
Authors: Muramatsu Motohiko , Umemura Setsuko 
Published: July 2016

Abstract
In this paper, thermal analyses (thermogravimetry, TG: derivative thermogravimetry, DTG: differential scanning calorimetry, DSC) of the tobacco char left after pyrolysis of tobacco shreds were carried out in a nitrogen atmosphere containing given amounts of oxygen under a linear heating or an isothermal condition. The principal object of the present work is to obtain apparent kinetic parameters useful in predicting the overall rate of the tobacco char - oxygen reaction. The TG-DTG-DSC curves obtained under linear heating conditions showed that the oxidation process of the tobacco char apparently consisted of two main steps ( I and II), which were independent of each other. Assuming that a uniform reaction model based on reaction rate - determined processes could be applied to the tobacco char - oxygen reactions in both steps, the oxidation rates for both steps were determined. The results showed that the oxidation rates of both steps could be expressed as:

The values of activation energies, E, and pre-exponential factors, Z, for the oxidation reactions in steps I and II were found to be 19-21, 33-40 kcal/mol and 5.9 × 105-5.7x 106, 5.5 × 109 4.5 × 1011/ min atm1/2, respectively.
Nomenclature
As reactant (solid phase, tobacco char)
E activation energy [kcal mol-1, 1 cal = 4.184 J]
po2,∞ ambient oxygen partial pressure [atm, 1 atm = 1.013 × 105 Pa]
R gas constant [ 1.98 cal mol-1 K-1]
T temperature [K]
t time [min]
W weight loss of tobacco char up to time, t, or temperature, T [mg]
Wc weight loss of tobacco char at completion of reaction [mg]
Z pre-exponential factor [min-1 atm-m]
a fraction of As decomposed at time, t, defined by a = W/Wc
A Study of Chemical Deliveries as a Function of Cigarette Butt Length
Authors: Young J. C. , Robinson J. C. , Rickert W. S. 
Published: July 2016

Abstract
It should be emphasized that the major conclusion of this paper is not that any particular parameter is linear on any particular scale, but that there are highly significant differences in slope, intercept and perhaps even linearity between brand groups and even brands within groups. In fact, although several brands do seem to be adequately linear on either arithmetic or logarithmic scales they very clearly do behave differently from each other. There is also quite strong evidence that condensate and nicotine are not linear on the same scale, with condensate being approximately linear on the logarithmic scale and nicotine approximately linear on the arithmetic scale. On the basis of the above it is quite clear that the ranking of brands on the basis of measured value of any parameter will depend strongly on the butt length at which the parameter was measured. It is therefore apparent that international comparison of deliveries requires redetermination of deliveries at the new butt length standard rather than mathematical manipulation using a single functional relationship. The form of a suitable functional relationship for HCN cannot be ascertained from the present study and will require additional experimentation. The statistical design and analysis proved worthwhile in model discrimination for the other three parameters.
Altering Condensate Levels in Tobacco Smoke by Genetic Techniques
Authors: Chaplin James F. , Spurr Harvey W. 
Published: July 2016

AbstractCondensate deliveries from cigarettes can be reduced by manufacturers in various ways. Lines or cultivars of tobacco can also be developed whose cured leaf, upon pyrolysis, delivers less condensate in the smoke. Since there appears to be an association between condensate and nicotine in smoke, the condensate : nicotine ratio is important to the development of lines of tobacco that deliver low condensate levels. Experiments were conducted to evaluate the potential for genetically controlling condensate delivery in cigarette smoke and data are presented. In general, when comparing the condensate delivery potential for different classes of tobacco, Burley delivered higher condensate values followed by dark fire-cured, dark air-cured, flue-cured and Maryland cultivars. In selecting genotypes for lowering condensate deliveries, the condensate / g of tobacco smoked is a better index than condensate/cigarette. In evaluating low-alkaloid tobaccos, the condensate delivery did not decrease appreciably as the total alkaloids were decreased. On an average, the decrease was about 4 mg of condensate / cigarette when compared with normal-alkaloid types but the condensate : nicotine ratio increased greatly. The ratio of condensate : nicotine was lowered when lines high in nicotine were produced. In one test reported, the ratio of condensate : nicotine ranged from 5.3 (TI 717) to 75.0 for a low-nicotine line. N. rustica had higher nicotine than N. tabacum cultivars and a lower condensate : nicotine ratio. The gene(s) responsible for the production of nicotine in N. rustica were transferred into N. tabacum and some of the derived lines had a nicotine content about 1 % higher than SC 58, the highest-nicotine cultivar, or flue-cured tobacco available. The condensate delivery / g of tobacco smoked was lower for these lines when compared with SC 58. All of the lines tested gave a condensate : nicotine ratio lower than SC 58. The data showed that condensate deliveries from tobaccos vary with the environment, cultural practices and the weather conditions under which the tobacco is produced. To make progress in breeding for lower condensate delivery in tobacco, it is necessary to assay large numbers of samples and methods for doing this were discussed. To breed low-condensate delivery lines with good smoking flavour, it will be necessary, simultaneously, to select for certain flavour compounds. More research is needed on flavour chemicals of tobacco and their relationship to condensate.
Variation of Sidestream Gas Formation during the Smoking Cycle
Authors: Baker R.R. 
Published: July 2016

AbstractExternal contour distributions for gas temperatures and for the concentrations of carbon monoxide, carbon dioxide, hydrogen and oxygen are reported at successive times in the smoking cycle. The sidestream gases leave the coal in a vertical column centering at about 3 mm in front of the paper burn line. The levels of oxygen and the carbon oxides outside the coal are not primarily determined by any diffusion gradient originating in the inner coal. Rather, the external levels are determined partly by a convective current set up by the hot coal, and influenced by buoyancy effects. The oxygen in the convection stream forms the oxides of carbon on the hot surface of the coal, and the convected air is transported around the coal in an upwards direction. On the other hand, the hydrogen levels outside the coal result from diffusion from the inner coal, although much of this outward diffusing hydrogen is oxidised to water on the surface of the coal. The visible sidestream smoke column is about 3 mm in diameter and its centre is about 5 mm behind the sidestream gas column, becoming visible when the temperatures in the gas column are below about 150°C. The vapour which eventually condenses to form mainstream and sidestream smoke is released in the general pyrolysis / distillation region of the cigarette, just behind the paper burn line. Some of this vapour diffuses to the outside of the cigarette, through the partially degraded paper, and it condenses to form the sidestream smoke particles once outside the coal.
Neutron Activation Analysis in Tobacco and Cigarette Smoke Studies: The Halogens
Authors: Jenkins R.W. , Newman R.H. , Lester G.F. , Frisch A.F. , Williamson T.G. 
Published: July 2016

AbstractThe mass balance for chlorine and bromine in the burning 1R1 Kentucky reference cigarette has been determined using neutron activation analyses. Gas radiochromatography has been used to measure dynamically the amounts of gamma-emitting isotopes as they elute from a gas chromatograph. The sidestream and mainstream gas phases which elute from a gas chromatograph appear to be qualitatively identical in their organohalogens, differing only in their quantitative values. The results show that a substantial conversion of ionic halides to organohalogens takes place during smoke formation and this transformation has a threshold temperature below that established during either the puffing or static burn modes of the cigarette. The chemical nature of the halogens present in the mainstream particulate smoke was 10.8 % organochlorine, 88.6 % ionic chloride, 13.3 % organobromine and 86.0 % ionic bromide
Surfactant Residues in Maryland Tobacco Treated with a Fatty-Alcohol-Type Sucker-Control Formulation
Authors: Cheng A.L.S. , Steffens G.L. 
Published: July 2016

AbstractSurfactant residues (Tween 80 Esters and Tween 80 free Polyols) were determined in Maryland tobacco treated with a fatty-alcohol-type sucker-control formulation. The levels of residues in leaves decreased throughout the growing and air-curing periods, but decreased the most during the first 24 hours after treatment. Factors affecting Tween 80 residue levels included dosage and location of leaves on the plant.
The Effect of Some Nitrogenous Blend Components on NO/NOx and HCN Levels in Mainstream and Sidestream Smoke
Authors: Norman V. , Ihrig A.M. , Larson T.M. , Moss B.L. 
Published: July 2016

AbstractVapour phase NO concentrations in mainstream and sidestream smoke correlated well with blend nitrate levels over the range from 0.07 to 3.70 %. Native and added nitrate fit the same correlation. No measurable amounts of NO
Study of the Action of Smoke on Alcohol Dehydrogenase, Lactic Dehydrogenase and Malate Dehydrogenase Enzymes
Authors: Neri M. , Carugno N. 
Published: July 2016

AbstractThe aim of this study is to acquire better knowledge of the action of the whole smoke and the vapour phase on alcohol dehydrogenase (ADH), lactic dehydrogenase (LDH), and malate dehydrogenase (MDH). The method developed provides that smoke comes into direct contact with the various enzymatic solutions without any preventive extraction, as in previous methods. It is based on the determination of the degree of inhibition of sulfhydryl reagent groups of enzyme by smoke. Additionally, the efficiency of cigarette filters for the reduction of this inhibition was evaluated. The purpose of this study also included the examination of the protective effect of thiol groups of enzymes against the inhibitory action of smoke. The results obtained show a high reactivity of smoke with sulfhydrylic groups of the enzymes examined. The effect of this reactivity is different for the three enzymes considered and dependent upon the role that sulfhydryl reagent groups had in the enzymatic activity. In particular, it was found that alcohol dehydrogenase, which needs all its sulfhydryl groups for its own activity, undergoes a strong inhibition due to smoke, while lactic dehydrogenase shows a negligible inhibition. The tests made have also shown the protective action of thiol on the inhibited enzymes.