The Experts below are selected from a list of 297 Experts worldwide ranked by ideXlab platform
Kwang Ho Kim - One of the best experts on this subject based on the ideXlab platform.
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Improvement of long-term stability in SnO2-based gas sensor for monitoring Offensive Odor
Sensors and Actuators B-chemical, 1999Co-Authors: Jong-hyun Park, Kwang Ho KimAbstract:Abstract WO 3 /SnO 2 ceramics has been suggested as an effective sensing material for monitoring Offensive Odor or pollutant gases. This work was focused on improving long-term stability, which has been a principal problem generally associated with SnO 2 semiconductor gas sensors. Miniaturized thick film gas sensors were fabricated by screen-printing technique. Two types of sensor materials, W-doped SnO 2 and WO 3 -mixed SnO 2 , were comparatively investigated with respect to long-term stability and sensitivity to several gases. Small amount of W doping (0.1 mol%) into SnO 2 largely improved the long-term stability. The W (0.1 mol%)-doped SnO 2 gas sensor had higher sensitivity to both acetone and alcohol compared with WO 3 (5 wt.%)-mixed SnO 2 gas sensor. On the contrary, WO 3 (5 wt.%)-mixed SnO 2 gas sensor showed superior sensitivity to cigarette smoke due to larger W content.
Makoto Misono - One of the best experts on this subject based on the ideXlab platform.
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effect of additives and particle size on the sensitivity of sno2 based sensors for Offensive Odor components
Sensors and Actuators B-chemical, 1993Co-Authors: Yukiko Nishizaka, Chikafumi Yokoyama, Kei Inumaru, Toshio Okuhara, Makoto MisonoAbstract:Abstract The sensing mechanism of an SnO 2 sensor as well as the effects of additives on its sensitivity for trimethylamine (TMA), (CH 3 ) 3 N, have been studied. The conductance changes reversibly and greatly upon the change between N 2 and N 2 + (CH 3 ) 3 N, while the change is small upon exposure to O 2 . Hence, it is concluded that the electron-donating adsorption of TMA is the key step in determining the change in the conductance. The addition of La to SnO 2 greatly enhances the sensitivity, whereas transition metals like Cr, Cu, Mn, etc., have opposite effects. The sensitivity is correlated almost inversely with the catalytic activity of the sensor for oxidation of TMA. The particle size of SnO 2 and the loading amount of La are also influential in determining the sensitivity. Therefore, a probable mechanism for the increase in sensitivity is that La enhances, by supressing the catalytic oxidation of trimethylamine, the supply of trimethylamine to the neck formed between SnO 2 particles, at which the conductance is mainly determined.
Hu J - One of the best experts on this subject based on the ideXlab platform.
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large scale synthesis of water soluble polymeric product of glu ala maillard reaction and its application in tobacco
Tobacco Science & Technology, 2010Co-Authors: Hu JAbstract:In order to industrialize the production of water-soluble Maillard reaction polymeric product,the synthetic conditions influencing the product of glucose/alanine ( Glu/Ala) Maillard reaction were investigated, including proportion of input materials,heating mode,reaction time and isolation method. The results showed that: 1) the appropriate synthetic conditions were: input ratio of Glu/Ala 1∶ 1 ( molar ratio) ,NaHCO3 4% , reaction temperature 95 ℃,reaction time 24 to 30 hours,and product isolation by alcohol precipitation or spray-drying. 2) The aroma quantity,Offensive Odor,smoke concentration,smoothness,irritancy,aftertaste of cigarette smoke were improved to different degrees by adding the synthetic product,particularly in aroma quantity,Offensive Odor,and smoothness. The smoking aroma was more significantly improved by an alcohol precipitation product,while taste was more obviously enhanced by a spray-drying product.
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Large-scale Synthesis of Water-soluble Polymeric Product of Glu/Ala Maillard Reaction and its Application in Tobacco
Tobacco Science & Technology, 2010Co-Authors: Hu JAbstract:In order to industrialize the production of water-soluble Maillard reaction polymeric product,the synthetic conditions influencing the product of glucose/alanine ( Glu/Ala) Maillard reaction were investigated, including proportion of input materials,heating mode,reaction time and isolation method. The results showed that: 1) the appropriate synthetic conditions were: input ratio of Glu/Ala 1∶ 1 ( molar ratio) ,NaHCO3 4% , reaction temperature 95 ℃,reaction time 24 to 30 hours,and product isolation by alcohol precipitation or spray-drying. 2) The aroma quantity,Offensive Odor,smoke concentration,smoothness,irritancy,aftertaste of cigarette smoke were improved to different degrees by adding the synthetic product,particularly in aroma quantity,Offensive Odor,and smoothness. The smoking aroma was more significantly improved by an alcohol precipitation product,while taste was more obviously enhanced by a spray-drying product.
Kazunori Sugahara - One of the best experts on this subject based on the ideXlab platform.
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The discrimination of many kinds of Odor species using fuzzy reasoning and neural networks
Sensors and Actuators A: Physical, 1994Co-Authors: Byeongdeok Yea, Ryosuke Konishi, Tomoyuki Osaki, Kazunori SugaharaAbstract:Abstract To discriminate many kinds of Odor species, a system composed of multiple gas sensors and neural networks is proposed. Three commercial gas sensors are used for the system, and four kinds of inflammable gases, four kinds of fragrant smells and one kind of Offensive Odor are introduced as Odor species. The discrimination is performed in two steps to increase the efficiency of the system; the first step is classification of the Odor group, that is, the groups of inflammable gases, fragrant smells and Offensive Odor; the second step is the discrimination of individual Odor species in the classified group. 100% group classification rate is obtained by the use of simple fuzzy reasoning and the steady-state response patterns of the sensors. The discrimination of individual Odor species is performed with a neural network and transient response patterns of the sensors and a high discrimination rate (99.2%) is achieved.
Jong-hyun Park - One of the best experts on this subject based on the ideXlab platform.
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Improvement of long-term stability in SnO2-based gas sensor for monitoring Offensive Odor
Sensors and Actuators B-chemical, 1999Co-Authors: Jong-hyun Park, Kwang Ho KimAbstract:Abstract WO 3 /SnO 2 ceramics has been suggested as an effective sensing material for monitoring Offensive Odor or pollutant gases. This work was focused on improving long-term stability, which has been a principal problem generally associated with SnO 2 semiconductor gas sensors. Miniaturized thick film gas sensors were fabricated by screen-printing technique. Two types of sensor materials, W-doped SnO 2 and WO 3 -mixed SnO 2 , were comparatively investigated with respect to long-term stability and sensitivity to several gases. Small amount of W doping (0.1 mol%) into SnO 2 largely improved the long-term stability. The W (0.1 mol%)-doped SnO 2 gas sensor had higher sensitivity to both acetone and alcohol compared with WO 3 (5 wt.%)-mixed SnO 2 gas sensor. On the contrary, WO 3 (5 wt.%)-mixed SnO 2 gas sensor showed superior sensitivity to cigarette smoke due to larger W content.
