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Volume 32 (1982)
- Issue 2 Pages 43-
- Issue 1 Pages 1-
Volume 32, Issue 2
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Tadahisa JIN1982 Volume 32 Issue 2 Pages 43-47
Published: 1982
Released on J-STAGE: October 23, 2012
JOURNAL FREE ACCESSIt was pursued haw the decrease in the thinking power and memory reduce in smoke. The decrease in thinking power was estimated by means of the changes of correct answer rate of mental calculation. The reduction of memory was estimated how the order of four kinds of color panel could be remembered in the smoke.
Thinking power decreased with increase of smoke concentration, even in thin smoke concentration. It was clear that the apparent reduction in memory came out when the optical smoke density exceeded over 0.4/m expressed in extinction coefficient.
Changes of thinking power and reduction in memory after having alcohol were also pursued in same method as aforementioned system.View full abstractDownload PDF (262K) -
H. OHTANI, T. HIRANO, K. AKITA1982 Volume 32 Issue 2 Pages 49-55
Published: 1982
Released on J-STAGE: October 23, 2012
JOURNAL FREE ACCESSA kinetic analysis on pyrolysis of Polymethylmethacrylate (PMMA) under fire conditions was performed by the thermal gravimetric analysis (TG) method. Heating rates of PMMA samples adopted in this study to simulate fire conditions were 10, 20, 30, 40 and 50 °C/min which were relatively high heating rates in comparison with those adopted in usual studies for examining thermal properties of polymers. The amount of a sample (ca. 5 mg) adopted in each run was restricted to be as small as possible to minimize temperature difference in the sample.
Two peaks were found in each weight loss rate (DTG) curve. These peaks correspond to two different reactions. Initiation temperatures of these reactions show that the first stage in pyrolysis reaction of PMMA is end-initiated and the second is initiated by random chain scissions. End-initiated pyrolysis reaction takes place for molecules with unsaturated chain-ends. Experimentally confirmed fraction of molecules with unsaturated chain-ends were about 0.22 and 0.25-0.28 for Acrylite AR (Mitsubishi Rayon Co.) and Plexiglas G (Rohm and Haas Co.), respectively.
Activation energies for each reaction under different conditions and different samples were estimated from experimentally obtained TG and DTG curves. Estimated activation energies for pyrolysis reaction of Acrylite AR were 51 kcal/mol in N2 and 44 kcal/mol in air at the first peak and 22 kcal/mol in N2 and 18 kcal/mol in air at the second peak, and those of Plexiglas G were 39 kcal/mol in N2 and 40 kcal/mol in air at the first peak and 20 kcal/mol in N2 and 21 kcal/mol in air at the second peak. Activation energies for pyrolysis reaction of Acrylite AR depend on its atmosphere. On the other hand, Plexiglas G were nearly independent of its atmosphere. For either Acrylite AR or Plexiglas G, the activation energy at the first peak was almost twice of that at the second peak.View full abstractDownload PDF (522K) -
Kenjiro YASUNO, Hiroyuki TAKAI, Yoshiro NAMBA1982 Volume 32 Issue 2 Pages 57-65
Published: 1982
Released on J-STAGE: October 23, 2012
JOURNAL FREE ACCESSIn this paper, we consider the effectiveness of suppression of wooden building fire by the use of water and by varying the beginning time of water application. Several parameters and functions concerning the effectiveness are obtained by analyzing the data of real fires in K city.
Furthermore the effectiveness is simulated by using standard fire condition, G = 300 m2 and ν = 3.0 m/sec, in eq. (4-1) as a case of fire model.
Following results are obtained:
(1) Burnt Area A(t) which is influenced by water application can be calculated by using eq. (3-10) and eq. (3-11).
(2) Necessary water application coefficient q0 can be expressed by the function Burnt Area A0 And coefficient q0 is shown by eq. (4-3) from the method of non-linear least squares.
(3) The water application rate Q is expressed by the function t (time from the beginning of water application). Q2 (a case of the average in K city; eq. (4-6)) is adequate three fire engines if one fire engine's water application rate is expected 1.0-1.2 m3 /min.
(4) It is proved that the necessary and enough number of fire engines is three if the fire area is under 100 m2, and if the water application begins within 10 min. from fire broken out.
(5) We refer to the estimation method of parameters in eq. (3-2), which is the fire spread of formula without fire fighting from applying the method of least squares to eq. (3-6) by using the data of real fire fighting.View full abstractDownload PDF (612K)
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