bluuebunny/crossref_metadata_2025_split huggingface dataset:
Evaluation of a Tobacco Fractionation Procedure Using Pyrolysis Mass Spectrometry Combined with Multivariate Analysis
Authors: Scheijen MA , Brandt-de Boer B , Boon JJ , Hass W , Heemann V 
Published: July 2016

Abstract
This paper presents an evaluation of a fractionation procedure for use with tobacco. Correlation coefficients calculated from the weights of the polymer fractions obtained and data obtained with classical wet-chemical methods show that these parameters have a low resolving power, which precludes any detailed distinction between tobaccos and tobacco-derived fractions. Pyrolysis mass spectrometry combined with multivariate analysis is presented as a promising approach for investigating the variability in the chemical composition of tobacco. Multivariate analysis performed on the pyrolysis mass-spectrometric fingerprints of all tobacco fractions indicates that the differences between the individual tobaccos are smaller than the differences induced by the fractionation procedure. Multivariate analysis of subfiles of the pyrolysis mass-spectrometric fingerprints of separate polymer fractions is an excellent method for classifying tobaccos. Leaf and stem material can easily be distinguished. A further differentiation is made between the flue-cured and Burley-type tobaccos. The strong clustering of tobacco samples after treatment with potassium hydroxide points to a uniform cell-wall skeleton. The greater variability in the ethanolized tobacco samples, and samples subjected to hot-water extraction or amylase digestion, is related to the cytosol characteristics. These fractions appear to reflect both the dissimilarities between the distinct tobacco types and phenotypic variations due to differences in cultural management. Pyrolysis mass spectrometry of the Klason lignin residues points to a large variety of chemical constituents unrelated to lignin. Pyrolysis gas-chromatography mass-spectrometric data on the Klason lignin residues of a Burley tobacco showed that the correlation made between the organic-nitrogen content and the protein content of this fraction might be misleading. As a consequence the maximum value for the lignin content of this tobacco is estimated incorrectly.
Transfer of Added [18-14C]Octatriacontane - Cigarette Smoke Formation Studies
Authors: Bass RT , Brown LE , Hassam SB , Newell GC , Newman RH 
Published: July 2016

Abstract
Radiolabelled [18-14C]octatriacontane (C38H78) was used as a model compound to study the transfer of compounds from tobacco into smoke. Non-filter cigarettes were made from Kentucky reference 2R1 cigarette tobacco filler oversprayed with alkane and were smoked on a single-port total recovery smoking machine. Of the recovered activity nearly 60 % was found in the mainstream and sidestream particulate phases of smoke, 5 % in the gaseous phase and 35 % in the butt. Reverse-phase high-performance liquid radiochromatography and thin-layer radiochromatography were used effectively to analyse the cyclohexane extracts of the filler, mainstream and sidestream total particulate matter, and butt. No degradation of the alkane was observed prior to smoking. The radioactivity in the mainstream total particulate matter extracts consisted mostly of intact [14C]octatriacontane. Sidestream total particulate matter extracts contained both intact octatriacontane and breakdown products. The radioactivity in butt extracts consisted almost entirely of intact octatriacontane, indicating that excess radioactivity in the butt is due to filtration of the intact alkane by the filler rod. The transfer of octatriacontane into mainstream smoke without pyrolytic degradation parallels that of the tobacco alkane dotriacontane.
A Transient Method for Determining Thermal Diffusivity of Tobacco Stems
Authors: Barthakur NN , Arnold NP 
Published: July 2016

Abstract
A microwave generator and a closed-circuit wind tunnel were used to measure the thermal diffusivity of tobacco (Nicotianatabacum L.) stems in vivo by the unsteady-state method. A simple mathematical model for heat flow, based on Fourier's heat-conduction equation and Newton's law of cooling, was used in this study. The microwave method was found to be relatively rapid as both heating and cooling of a cylindrical stem in an air stream could be completed in approximately 30 minutes for thermal-diffusivity determinations. Thermal-diffusivity value of the tobacco stems, containing 94 % moisture and a mean stem temperature of 30°C, was found to be (1.38 ± 0.06) × 10-7 m2 s-1. The coefficient of variation for the measurements did not exceed 1.4 % as determined through the analysis of cooling curves for five different air-flow rates over the stems. This study showed that the microwave technique could be effectively used to determine both accurately and reliably the thermal diffusivity of tobacco stems in vivo.
Smoke Production from Cell Wall Materials of Tobacco Leaves
Authors: Ishizu Y , Kaneki K , Izawa K 
Published: July 2016

Abstract
Major components of cell wall materials, that is a-cellulose, hemicellulose, pectin and lignin, were isolated from tobacco leaves. They were heated in a micro-thermobalance in different atmospheres and at different heating rates. The weight loss rate of the sample materials, production rates of carbon oxides and smoke particles produced were measured. In general, materials which produce more carbon oxides produce less smoke particulate mass. In helium at a heating rate of 240°C/min, which attempts to approximate the burning conditions of a cigarette, weight ratios of smoke particles to the sample weight were 32 % for a-cellulose, 24 % for lignin, 3 % for hemicellulose and 0.4 % for pectin. Since a-cellulose is a major constituent of the cell wall of tobacco leaves and has the highest production rate, it can be concluded that a-cellulose is a major contributor to the production of smoke particles from cigarettes. On the contrary, pectin contributes the least.
The Determination of Benzo[a]Pyrene and Benz[a]Anthracene in Mainstream and Sidestream Smoke of the Kentucky Reference Cigarette 1R4F and a Cigarette Which Heats but Does Not Burn Tobacco: A Comparison
Authors: Risner CH 
Published: July 2016

Abstract
A quantitative method for the determination of benz[a]anthracene (B[a]A) and benzo[a]pyrene (B[a]P) in mainstream and sidestream cigarette smoke by high performance liquid chromatography (HPLC) has been developed. Mainstream and sidestream particulate matter is collected on Cambridge filter pads. The polycyclic aromatic hydrocarbons (PAH) are extracted with cyclohexane and subjected to normal-phase chromatography to isolate target fractions which are concentrated and then diluted with acetonitrile or acetonitrile/water prior to reverse-phase analytical chromatography. The Kentucky Reference cigarette 1R4F and a cigarette which heats but does not burn tobacco (New Cigarette) developed at R.J. Reynolds Tobacco Company were analysed and compared with respect to B[a]P and B[a]A in both mainstream and sidestream smoke.
Tobacco Leaf Protein: I. An Evaluation of the Use of Putative Chemical Growth Enhancers for Tobacco Leaf Protein Production
Authors: De Jong DW 
Published: July 2016

Abstract
Effects of foliar applications of long-chain fatty compounds on production of leaf protein from tobacco genotypes were evaluated. Triacontanol, purported to be a growth stimulant, had minimal effects on most experimental parameters. A propriety product, AgroLizer™, appeared to exert greater influence but results were inconclusive. Chemical treatments interacted with environmental conditions and tobacco genotype. Acid precipitation of the green fraction resulted in a pellet that could be easily removed by low speed centrifugation but produced a white fraction with lower protein percentage than heat precipitation of the green fraction. Triacontanol delayed flowering and extended vegetative growth in some genotypes. Increased cured leaf yields of flue-cured and Maryland type tobaccos were consistent but not statistically significant. An important finding was discovery of a genotype, T.I. 401, that produced high amounts of extractable leaf protein regardless of growth stage. This variety became the object of a follow-up investigation.
Time Resolved Emission of Sidestream Smoke Particles
Authors: Dittmann R , Feld HJ , Müller BH , Schneider W 
Published: July 2016

Abstract
By means of the dispersion quotient method, the aerosol properties of freshly produced sidestream smoke were measured during the puff and subsequent interpuff period. These measurements were made on short time scales and at high aerosol concentrations. Examples are presented, which show the influence of different combustion conditions during the puff (resulting from different degrees of ventilation and different types of tobacco) on the emission of sidestream particles during the interpuff period. The ratio of the volume concentrations of the particles before and during a puff is reduced by ventilation and is nearly unchanged by the variation of the tobacco type.
An Application of Fourier Transform Infra-red (FT-IR) Microspectroscopy to the Study of Cigarette Manufacturing Defects
Authors: Thompson MM , Ireland MS 
Published: July 2016

Abstract
FT-IR microspectroscopy was used to investigate a common type of cigarette defect in which the filter separates from the tobacco rod. Infra-red imagings of the adhesive located at this junction on the tipping papers from both defective and acceptable cigarettes were obtained. A comparison of these data revealed that although adhesive was present in the seam area of the defective cigarettes, the amount of adhesive was significantly less and its distribution was not uniform.
The Measurement of Intrapuff Nicotine Yield
Authors: Crooks EL , Lynm D 
Published: July 2016

Abstract
Time-resolved measurements of intrapuff nicotine yield in mainstream smoke have been performed with a specially designed intrapuff smoking apparatus (IPSA). The IPSA-filter traversing mechanism collects mainstream particles on a rectangular filter pad which moves at a constant velocity perpendicular to the direction of smoke flow at the mouthend of the cigarette. Filter pads were assayed by two analytical techniques. Standard gas chromatographic (GC) methodology was used to quantify nicotine mass in five equal time segments per puff. A second method, using a Berthold TLC-Linear Analyser, measured total radioactivity across the pad for samples from [2'-14C]-nicotine labelled cigarettes. Intrapuff nicotine concentrations were determined from measured puff flow-rate profiles and the collected masses of nicotine on the filters. GC nicotine concentration measurements correlated well with total activity from the scanner measurements. Studies carried out with filtered full-flavour cigarettes revealed that nicotine concentrations in the smoke vary significantly during a puff. This work provides a new technique for studying time-resolved yields of mainstream smoke components. It may potentially be used to elucidate mechanisms controlling the yield of nicotine and other mainstream smoke components.
Pattern-Arrangements of Tobacco Shreds in the Internal Structure of Cigarettes
Authors: Nestorov A , Vuthy C 
Published: July 2016

Abstract
Analyses of indices observed in macro-photographs of a variety of cigarette cross-sections have shown that tobacco shreds forming the internal structure of cigarettes are highly arranged in a defined pattern in which their lenghts are predominantly oriented along the cigarette lenghts and their widths - parallel to the cigarette seams. These pattern-arrangements of tobacco shreds have an effect upon the dielectric properties and deformation of cigarettes. The deformation has been found to be bigger when measured perpendicular to seams.
Tobacco and the Environment: The Continuous Reduction of Worldwide Energy Source Use for Green Leaf Curing
Authors: Campbell JS 
Published: July 2016

Abstract
Air-, flue-, fire-, and sun-cured, tobacco types require post-harvest curing of green leaves to produce optimum subjective and objective qualities for storage and subsequent processing and manufacture. Materials for construction of curing barns vary widely between countries. The major use of heating fuels within such structures is for flue-cured tobacco. Choice of energy sources, coal, wood, oil or gas depends on local availability, cost, and relative efficiencies. The vital importance of reducing such materials to a minimum has been recognised for many years by research into improving barn and furnace design and construction. Consumption of wood for curing has been shown to represent a minute proportion of total world wide consumer use. To ensure local availability, the growing of trees by flue cured farmers on a personal, self-sufficient, sustainable basis is well underway in parts of Africa, Asia, and South and Central America. Tobacco production, within an environmental farming system, on an economic basis, is discussed and strongly stressed.
The Biological Degradation of Nicotine by Nicotinophilic Microorganisms
Authors: Eberhardt HJ 
Published: July 2016

Abstract
Various microorganisms are capable of breaking down tobacco alkaloids by different biochemical processes and possess characteristic enzymatic systems for the catabolism of nicotine. Bacteria of the genus Pseudomonas and the fungus Cunninghamellaechinulata degrade nicotine via N-methylmyosmine and pseudooxynicotine which is linked to the opening of the pyrrolidine ring (pyrrolidine pathway), whereas Arthrobacteroxidanshydroxylates the pyridine ring in the 6-position. 6-hydroxynicotine is produced as a primary product (pyridine pathway). Tobacco plants, and some fungi (e.g. Pelliculariafilamentosa) degrade nicotine via demethylation to nornicotine (methyl pathway). As a result of the microbial degradation of nicotine and other tobacco alkaloids, carbon and nitrogen are made bioavailable. Following metabolic conversion to carboxylic acids, the reaction products are used by unicellular organisms as primary nutrients and a source of energy for the synthesis of new cell compounds.
Measurement of Dynamic Mass Changes in Burning Cigarettes by Neutron Radioscopy
Authors: Brenizer JS , Jenkins RW , Lanzillotti HV , McRae DD , Mora CA 
Published: July 2016

Abstract
Neutron radioscopic images of burning cigarettes under both static and dynamic smoking conditions were analysed with a video image processor to measure the changes occurring in the images. These changes were related to the actual mass changes occurring in the cigarette rod during the burning process. The neutron images were used to determine the deposition, movement and evaporation of pyrolysis products in the cigarette rod. In addition, the experimental data were used to calculate the mass burn rates of cigarettes. While the instantaneous mass burn rate of a smouldering cigarette can be measured with a balance, neutron radioscopy can be used to determine it under both static and dynamic smoking conditions. The results of this study, along with background information on neutron radioscopy, calibration methods and the image processing procedures, are presented.
Tobacco Production in Switzerland
Authors: Alber G 
Published: July 2016

Abstract
In Switzerland approximately 730 ha of tobacco are grown, mainly on small family farms. The main growing area is located in the French speaking part of the country, on altitudes ranging from 400 to 800 m above sea level. Approximately 93 % of the surface is planted with Burley and 7 % with Virginia. The cigarette manufacturers have to buy the whole crop of acceptable quality by law proportionally to their market share in Switzerland, in total approximately 1300-1500 tons per year. The buying organization, named SOTA (Societe cooperative pour l'achat du tabac indigene) has been created by the industry in 1930. It is responsible to buy and distribute the whole crop and finances a small research center with the aim to improve the quality. There is an agreement between the SOTA and the grower's organization FAPTA (Federation suisse des associations de planteurs de tabac) that limits the maximum surface to 730 ha. The price paid to the farmer is fixed by the government and is significantly higher than the world market price. The difference between the price paid to the farmer and the one paid by the industry is compensated by a specific fund which is under supervision of the custom and excise department. Because of several good crops, this system of subsidy became problematic. Therefore a new system of quota has been introduced for the 1997/1998 crop which limits the quantity of tobacco which can be delivered by each farmer.
Conference Report - Systemic Acquired Resistance (SAR): A Meeting Organized by the Pesticide Group of the Society of the Chemical Industry, March 10, 1998, London, UK
Authors: Eberhardt HJ 
Published: July 2016

Abstract
Conference Report Systemic Acquired Resistance (SAR): a meeting organized by the pesticide group of the society of the chemical industry, march 10, 1998, London, UK
Induction of Pathogenesis-Related Proteins of Group 1 by Systemic Virus Infections of Nicotiana tabacum L.
Authors: Röhring C 
Published: July 2016

Abstract
The induction of acid pathogenesis-related proteins (PR-proteins) of group 1 (PR-1) by systemic virus infections of tobacco plants was investigated during a time period between 3 and 19 days after inoculation. Each leaf position was investigated separately. The PR proteins were detected electrophoretically and, in addition, virus protein was detected by Enzyme Linked Immunosorbent Assay (ELISA). Potato virus X (PVX) and potato virus Y (PVY) were found to highly induce PR proteins in N. tabacum L. “Samsun NN”. The same results were obtained when PVX was investigated in N. tabacum L. “Samsun”. The accumulation started later and took place more slowly than during hypersensitive host reaction (HR) of “Samsun NN” to tobacco mosaic virus (TMV). A correlation was found between the accumulation of PR proteins and the accumulation of the virus in the same leaf. Cucumber mosaic virus (CMV) was less effective in PR protein induction than PVX and PVY. Consequently it could be demonstrated that PR proteins do not only appear due to hypersensitive host reactions but also during systemic virus infections.
Determination of Mainstream and Sidestream Cigarette Smoke Components for Cigarettes of Different Tobacco Types and a Set of Reference Cigarettes
Authors: Perfetti TA , Coleman WM , Smith WS 
Published: July 2016

Abstract
The yield of selected components in the mainstream and sidestream smoke for cigarettes of different tobacco types and a set of Kentucky Reference cigarettes have been measured. The BAT ‘fishtail’ chimney apparatus was used in conjunction with standard FTC Cambridge pad collection apparatus for the simultaneous collection of both sidestream (SS) and mainstream (MS) cigarette smoke, respectively. Comparison of MS FTC yields and MS yields from the BAT MS/SS smoke collection device showed that the smoke yields for the products of this study were similar for the two methods. Sidestream to mainstream smoke ratios (SS/MS) for TPM, nicotine, HO, ‘tar’, CO and COwere similar to those reported in the literature, despite the variety of collection devices employed in literature reports. The total nicotine accountabilities for the single tobacco cigarettes and the set of Reference cigarettes of this study were relatively constant (~53 %). Enantiomeric separation of the alkaloids in the different smoke streams was accomplished by chiral gas chromatography-mass selective detection. The levels and the enantiomeric ratios of nicotine and nornicotine varied in the smoke streams of the different cigarettes. The level and enantiomeric ratios of anaba-sine and anatabine in sidestream smoke were below detection limits of the method employed. The enantio-meric ratios of these secondary alkaloids could not be calculated. The fraction ofd -nicotine transferred to side-stream smoke did not change significantly when compared to that yielded in mainstream smoke even though the temperatures experienced during the side-stream smoke formation process are quite different (lower) from those occurring in the mainstream smoke formation process. Relatively low concentrations of the secondary alkaloids provided only a preliminary evaluation of their enantiomeric distribution in cigarette smoke.
Conference Report: 52nd Tobacco Science Research Conference (TSRC), September 13-16, 1998, Atlanta, Georgia, USA
Authors: Eberhardt HJ , Scherer G 
Published: July 2016

Abstract
The 52nd Tobacco Science Research Conference (TSRC) was held from 13th to 16th September 1998 in Atlanta, U.S.A., at the invitation of the University of Georgia, Atlanta. Two parallel sessions were held during which 64 papers were presented dealing with the results of recent biotechnological research with respect to the tobacco plant, as well as research into the manufacture and analysis of tobacco products, human smoking behaviour and the effects of pyrolytic products on the environment and the organism.
Conference Report: 51st German Plant Protection Conference, October 5-8, 1998, in Halle/Saale, Germany
Authors: Eberhardt HJ 
Published: July 2016

Abstract
The 51st German Plant Protection Conference was held by the Federal Biological Institute of Agriculture and Forestry [BiologischeBundesanstaltfür Land- und Forstwirtschaft] in Halle/Saale from 5th to 8th October 1998. The attendance of over 1,000 registered participants reflected the continued lively interest shown in the conference. Some 330 oral contributions, assigned to the various sections, were presented in five parallel sessions.