R. Rohr, A. Eberhard, R. Delon, Jp Descombes, Jm Demor
Abstract Tobacco leaf texture, appreciated by the difference of surface roughness of cured leaves, is studies with light microscopy and scanning electron microscopy (SEM). The leaf texture is obviously determined by the presence or absence of conical cellular protuberances on the adaxial side of the leaf. Considering the anatomic point of view, the leaf thickness, always more important when the leaf texture is open, is the only objective criterion which could be associated to the texture. The ultra-structural study with SEM and transmission electron microscopy (TEM) demonstrates that the expansion capacity of tobacco doesn't rely on cytological factors such as cellular reserves or debris. The expansion capacity could be inversely proportional with the relative importance of the mesophyll comparing to palisade parenchyma. On the studied material, no direct relation between the leaf texture and the expansion capacity has been noticed.
{"title":"Comparative Study of Leaf Surface Texture and Ability to Expand of Cured Tobacco","authors":"R. Rohr, A. Eberhard, R. Delon, Jp Descombes, Jm Demor","doi":"10.2478/CTTR-2013-0720","DOIUrl":"https://doi.org/10.2478/CTTR-2013-0720","url":null,"abstract":"Abstract Tobacco leaf texture, appreciated by the difference of surface roughness of cured leaves, is studies with light microscopy and scanning electron microscopy (SEM). The leaf texture is obviously determined by the presence or absence of conical cellular protuberances on the adaxial side of the leaf. Considering the anatomic point of view, the leaf thickness, always more important when the leaf texture is open, is the only objective criterion which could be associated to the texture. The ultra-structural study with SEM and transmission electron microscopy (TEM) demonstrates that the expansion capacity of tobacco doesn't rely on cytological factors such as cellular reserves or debris. The expansion capacity could be inversely proportional with the relative importance of the mesophyll comparing to palisade parenchyma. On the studied material, no direct relation between the leaf texture and the expansion capacity has been noticed.","PeriodicalId":10723,"journal":{"name":"Contributions to Tobacco & Nicotine Research","volume":"98 1","pages":"333 - 338"},"PeriodicalIF":0.0,"publicationDate":"2001-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"73619491","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Abstract The international community working in the field of indoor air research gathers every three years to discuss the state-of-the-art. In Nagoya, Japan, some 900 scientists from more than 50 countries met. More than 600 papers were presented in the form of keynote lectures, plenary lectures, lectures in technical sessions and posters. Special issues were discussed in 16 workshops. The papers have been published in four proceeding volumes with almost 4000 pages.
{"title":"Conference Report - 7th International Conference on Indoor Air Quality and Climate (Indoor Air 96) July 21-26, 1996, Nagoya, Japan","authors":"G. Scherer","doi":"10.2478/cttr-2013-0649","DOIUrl":"https://doi.org/10.2478/cttr-2013-0649","url":null,"abstract":"Abstract The international community working in the field of indoor air research gathers every three years to discuss the state-of-the-art. In Nagoya, Japan, some 900 scientists from more than 50 countries met. More than 600 papers were presented in the form of keynote lectures, plenary lectures, lectures in technical sessions and posters. Special issues were discussed in 16 workshops. The papers have been published in four proceeding volumes with almost 4000 pages.","PeriodicalId":10723,"journal":{"name":"Contributions to Tobacco & Nicotine Research","volume":"43 1","pages":"15 - 16"},"PeriodicalIF":0.0,"publicationDate":"1996-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"88053548","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Abstract From 23.-26. September 1996 the Biologische Bundesanstalt fuer Land- und Forstwirtschaft heldthe 50th ‘Deutsche Pflanzenschutztagung’ (German Plant Protection Conference) in Muensterwithmorethan 1000 participants. Approximately 350 presentations were classified into different specialities which were discussed in five parallel sessions. In addition, a poster session with 250 posters also included the culture and pesticide protection of the tobacco plant. The subjects treated in the various sessions were very broud. Besides the increasing importance of natural plant protection agents, modern biotechnological and genetic methods used for pest control and analysis of pest organisms in cultivars were a major discussion topic. Manufacturers of agrochemicals used the opportunity to present their newly developed products.
{"title":"Conference Report - 50th “Deutsche Pflanzenschutztagung”, September 23-26, 1996, Muenster, Germany","authors":"H. Eberhardt","doi":"10.2478/cttr-2013-0650","DOIUrl":"https://doi.org/10.2478/cttr-2013-0650","url":null,"abstract":"Abstract From 23.-26. September 1996 the Biologische Bundesanstalt fuer Land- und Forstwirtschaft heldthe 50th ‘Deutsche Pflanzenschutztagung’ (German Plant Protection Conference) in Muensterwithmorethan 1000 participants. Approximately 350 presentations were classified into different specialities which were discussed in five parallel sessions. In addition, a poster session with 250 posters also included the culture and pesticide protection of the tobacco plant. The subjects treated in the various sessions were very broud. Besides the increasing importance of natural plant protection agents, modern biotechnological and genetic methods used for pest control and analysis of pest organisms in cultivars were a major discussion topic. Manufacturers of agrochemicals used the opportunity to present their newly developed products.","PeriodicalId":10723,"journal":{"name":"Contributions to Tobacco & Nicotine Research","volume":"39 1","pages":"17 - 19"},"PeriodicalIF":0.0,"publicationDate":"1996-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"73184043","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
J. Brenizer, R. Jenkins, H. Lanzillotti, D. Mcrae, Carlos Mora
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.
{"title":"Measurement of Dynamic Mass Changes in Burning Cigarettes by Neutron Radioscopy","authors":"J. Brenizer, R. Jenkins, H. Lanzillotti, D. Mcrae, Carlos Mora","doi":"10.2478/CTTR-2013-0648","DOIUrl":"https://doi.org/10.2478/CTTR-2013-0648","url":null,"abstract":"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.","PeriodicalId":10723,"journal":{"name":"Contributions to Tobacco & Nicotine Research","volume":"99 1","pages":"3 - 13"},"PeriodicalIF":0.0,"publicationDate":"1996-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"79017062","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Abstract Deliveries of tar, nicotine and carbon monoxide in mainstream smoke decreased as the exogenous-potassium content of tobacco increased. The puff count was almost unchanged with added potassium malate, but slightly decreased with added nitrate. Potassium malate was more effective than the nitrate for the reduction of carbon monoxide, whereas the opposite was observed in the case of nicotine. Both the exogenous and the endogenous potassium contents influenced the reduction of carbon-monoxide delivery through a decrease in the peak temperature of the burning cone. The pungency and off-taste peculiar to the tobacco were eliminated to some extent by the addition of potassium malate at levels less than 2 % expressed as potassium.
{"title":"Effect of Exogenous Potassium on the Reduction in Tar, Nicotine and Carbon Monoxide Deliveries in the Mainstream Smoke of Cigarettes","authors":"T. Yamamoto, S. Umemura, H. Kaneko","doi":"10.2478/CTTR-2013-0613","DOIUrl":"https://doi.org/10.2478/CTTR-2013-0613","url":null,"abstract":"Abstract Deliveries of tar, nicotine and carbon monoxide in mainstream smoke decreased as the exogenous-potassium content of tobacco increased. The puff count was almost unchanged with added potassium malate, but slightly decreased with added nitrate. Potassium malate was more effective than the nitrate for the reduction of carbon monoxide, whereas the opposite was observed in the case of nicotine. Both the exogenous and the endogenous potassium contents influenced the reduction of carbon-monoxide delivery through a decrease in the peak temperature of the burning cone. The pungency and off-taste peculiar to the tobacco were eliminated to some extent by the addition of potassium malate at levels less than 2 % expressed as potassium.","PeriodicalId":10723,"journal":{"name":"Contributions to Tobacco & Nicotine Research","volume":"67 1","pages":"379 - 385"},"PeriodicalIF":0.0,"publicationDate":"1990-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"81594718","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Abstract A simple and general mathematical model has been developed to calculate filter-filtration efficiency, which is based on practical design parameters: pressure drop, filter dimension, flow rate, and filament denier. This model has been verified by examining published experimental data, which include a broad range of design parameters. This model surpasses other models currently described in the literature in terms of accuracy. The drag force of the filter (which is accounted for by the pressure drop times the circumference squared, DP • C2) appears to be the most important contribution to filter-filtration efficiency, but its contribution can be drastically reduced by varying design parameters.
{"title":"Practical Modeling of Filter Filtration Efficiency","authors":"J. Kao","doi":"10.2478/CTTR-2013-0611","DOIUrl":"https://doi.org/10.2478/CTTR-2013-0611","url":null,"abstract":"Abstract A simple and general mathematical model has been developed to calculate filter-filtration efficiency, which is based on practical design parameters: pressure drop, filter dimension, flow rate, and filament denier. This model has been verified by examining published experimental data, which include a broad range of design parameters. This model surpasses other models currently described in the literature in terms of accuracy. The drag force of the filter (which is accounted for by the pressure drop times the circumference squared, DP • C2) appears to be the most important contribution to filter-filtration efficiency, but its contribution can be drastically reduced by varying design parameters.","PeriodicalId":10723,"journal":{"name":"Contributions to Tobacco & Nicotine Research","volume":"1 1","pages":"341 - 352"},"PeriodicalIF":0.0,"publicationDate":"1990-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"89468395","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Abstract In summary, nuclear radiation has been widely used to elucidate many aspects of the mechanisms of tobacco being converted to smoke. In addition, the mechanisms of smoke transfer, tobacco inorganic chemistry and smoke filtration have been clarified by many authors worldwide. The newer techniques now being developed, using radiation detection coupled with the enhanced use of electronic-data reduction and interpretation, promise to continue the important role these techniques have played in understanding smoke-formation mechanisms.
{"title":"A Review of the Uses of Nuclear Radiation in Tobacco and Smoke Research","authors":"R. Jenkins","doi":"10.2478/CTTR-2013-0612","DOIUrl":"https://doi.org/10.2478/CTTR-2013-0612","url":null,"abstract":"Abstract In summary, nuclear radiation has been widely used to elucidate many aspects of the mechanisms of tobacco being converted to smoke. In addition, the mechanisms of smoke transfer, tobacco inorganic chemistry and smoke filtration have been clarified by many authors worldwide. The newer techniques now being developed, using radiation detection coupled with the enhanced use of electronic-data reduction and interpretation, promise to continue the important role these techniques have played in understanding smoke-formation mechanisms.","PeriodicalId":10723,"journal":{"name":"Contributions to Tobacco & Nicotine Research","volume":"522 1","pages":"353 - 378"},"PeriodicalIF":0.0,"publicationDate":"1990-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"75247952","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Abstract Plants from 64 Nicotiana species were sampled in the greenhouse in 1983 and 1984 and from the field in 1985 and 1986 for the purpose of developing a chemical profile of each species. Mature green leaves were harvested at flowering, freeze-dried and ground to pass a 1 mm screen prior to chemical analysis. In this study we report the type and amounts of nicotinoid alkaloids. Alkaloid values were determined by glass-capillary gas chromatography and were averaged over the two years for each environment. Both total alkaloids (mg g-1 dry weight) and the distribution (percentage composition) of nicotine, nornicotine, anabasine, and anatabine were highly correlated between years for greenhouse and field samples. Greenhouse and field data were highly correlated, although total-alkaloid levels were significantly higher from field-grown plants. All of the Nicotiana species tested contained a measurable alkaloid fraction (at least 10 µg g-1). There was a wide range in total-alkaloid levels with nearly a 200-fold difference among greenhouse-grown samples and a 400-fold difference among field-grown species. In general, total-alkaloid levels among the species were found to be relatively low. Eleven species were found to have a different alkaloid composition when green leaf and air-dried samples were compared. Evidence is presented for the association between alkaloid characteristics and the phylogenetic classification of the species in the genus.
{"title":"Alkaloid Composition of the Nicotiana Species","authors":"V. Sisson, R. Severson","doi":"10.2478/CTTR-2013-0610","DOIUrl":"https://doi.org/10.2478/CTTR-2013-0610","url":null,"abstract":"Abstract Plants from 64 Nicotiana species were sampled in the greenhouse in 1983 and 1984 and from the field in 1985 and 1986 for the purpose of developing a chemical profile of each species. Mature green leaves were harvested at flowering, freeze-dried and ground to pass a 1 mm screen prior to chemical analysis. In this study we report the type and amounts of nicotinoid alkaloids. Alkaloid values were determined by glass-capillary gas chromatography and were averaged over the two years for each environment. Both total alkaloids (mg g-1 dry weight) and the distribution (percentage composition) of nicotine, nornicotine, anabasine, and anatabine were highly correlated between years for greenhouse and field samples. Greenhouse and field data were highly correlated, although total-alkaloid levels were significantly higher from field-grown plants. All of the Nicotiana species tested contained a measurable alkaloid fraction (at least 10 µg g-1). There was a wide range in total-alkaloid levels with nearly a 200-fold difference among greenhouse-grown samples and a 400-fold difference among field-grown species. In general, total-alkaloid levels among the species were found to be relatively low. Eleven species were found to have a different alkaloid composition when green leaf and air-dried samples were compared. Evidence is presented for the association between alkaloid characteristics and the phylogenetic classification of the species in the genus.","PeriodicalId":10723,"journal":{"name":"Contributions to Tobacco & Nicotine Research","volume":"26 1","pages":"327 - 339"},"PeriodicalIF":0.0,"publicationDate":"1990-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"74632012","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Abstract The paper describes a method for the determination of polychlorinated dibenzodioxins and -furans both in gas phase and in particulate matter of cigarette smoke. This method was used for analysing the concentrations of all relevant polychlorinated dibenzofurans in the smoke of the ten best-selling German cigarette brands. The distribution of the various tetra-octachlordibenzodioxin isomers was similar to that obtained after combustion. None of the cigarettes investigated was found to contain 2,3,7,8-tetrachlordibenzodioxin. The total values expressed as TCDD toxic equivalent values are low, ranging from 0.05 to 0.17 pg/cig. These results are compared with the data reported in the literature to date. Regarding uptake of polychlorinated dibenzodioxins and -furans, cigarette smoke is only a source of minor importance as compared to nutrition.
{"title":"Polychlorinated Dibenzodioxins and Dibenzofurans in Cigarette Smoke - Polychlordibenzodioxine und Polychlordibenzofurane in Cigarettenrauch","authors":"M. Ball, O. Päpke, A. Lis","doi":"10.2478/CTTR-2013-0615","DOIUrl":"https://doi.org/10.2478/CTTR-2013-0615","url":null,"abstract":"Abstract The paper describes a method for the determination of polychlorinated dibenzodioxins and -furans both in gas phase and in particulate matter of cigarette smoke. This method was used for analysing the concentrations of all relevant polychlorinated dibenzofurans in the smoke of the ten best-selling German cigarette brands. The distribution of the various tetra-octachlordibenzodioxin isomers was similar to that obtained after combustion. None of the cigarettes investigated was found to contain 2,3,7,8-tetrachlordibenzodioxin. The total values expressed as TCDD toxic equivalent values are low, ranging from 0.05 to 0.17 pg/cig. These results are compared with the data reported in the literature to date. Regarding uptake of polychlorinated dibenzodioxins and -furans, cigarette smoke is only a source of minor importance as compared to nutrition.","PeriodicalId":10723,"journal":{"name":"Contributions to Tobacco & Nicotine Research","volume":"141 1","pages":"393 - 402"},"PeriodicalIF":0.0,"publicationDate":"1990-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"88305900","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
京公网安备 11010802042870号
京ICP备2023020795号-1
扫码关注我们
求助内容：
应助结果提醒方式：