Analysis of Vertical Combustion and Carbonization Patterns of Floor Materials When Using a Needle Flame

Min-Su Park; Chung-Seog Choi

doi:10.7731/kifse.96dca8eb

Analysis of Vertical Combustion and Carbonization Patterns of Floor Materials When Using a Needle Flame

Fire science and engineering ◽

10.7731/kifse.96dca8eb ◽

2020 ◽

Vol 34 (4) ◽

pp. 101-106

Author(s):

Min-Su Park ◽

Chung-Seog Choi

Keyword(s):

Fire Retardant ◽

Growth Characteristics ◽

Left And Right ◽

Laminated Layer

This study analyzed flame growth characteristics and carbonization patterns when floor materials were burned vertically using a needle flame produced for this study. It was found that PVC flooring was fire retardant and the area under direct flame contracted inward. Vertical combustion causes solidification in the form of a lump at the bottom and also generates soot in a pattern that progresses upwards. This study found that laminated flooring exhibited no fire retarding characteristics and that the laminated layer of its upper surface was destroyed by fire, causing irregular delamination. The carbonization ranges at the left and right sides were determined to be symmetrical. A vertical combustion test of a sample carpet showed that it exhibited no fire-retarding characteristics. It was observed that if heat accumulated in the carpet, the flame formed an ascending air current, and that when flammable materials were present around the flame, they further accelerated the diffusion of the flame. The carbonization pattern at the carpet surface exposed to direct flame revealed that the carpet surface had melted and had flown downwards and that many tiny holes formed on it.

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The three-dimensional structure of frozen-hydrated left- and right-handed forms of bacterial flagellar filaments from an identical serotype

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100143110 ◽

1986 ◽

Vol 44 ◽

pp. 298-299

Author(s):

S. Trachtenberg ◽

D. J. DeRosier

Keyword(s):

Ionic Strength ◽

Basal Body ◽

Three Dimensional ◽

Dimensional Structure ◽

Protein Species ◽

Liquid Environment ◽

Bacterial Flagellum ◽

Left And Right ◽

Rotary Motor ◽

Helical Parameters

The bacterial cell is propelled through the liquid environment by means of one or more rotating flagella. The bacterial flagellum is composed of a basal body (rotary motor), hook (universal coupler), and filament (propellor). The filament is a rigid helical assembly of only one protein species — flagellin. The filament can adopt different morphologies and change, reversibly, its helical parameters (pitch and hand) as a function of mechanical stress and chemical changes (pH, ionic strength) in the environment.

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Advantages of Complementary Stereo Images as Viewed with the Low-Temperature Field-Emission SEM

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100131206 ◽

1992 ◽

Vol 50 (2) ◽

pp. 1314-1315

Author(s):

William P. Wergin ◽

Eric F. Erbe

Keyword(s):

Fold Increase ◽

Horizontal Displacement ◽

Three Dimensions ◽

Stereo Image ◽

Stereo Pair ◽

Sem Micrograph ◽

Left And Right ◽

The Common ◽

The Brain ◽

Pair Analysis

The eye-brain complex allows those of us with normal vision to perceive and evaluate our surroundings in three-dimensions (3-D). The principle factor that makes this possible is parallax - the horizontal displacement of objects that results from the independent views that the left and right eyes detect and simultaneously transmit to the brain for superimposition. The common SEM micrograph is a 2-D representation of a 3-D specimen. Depriving the brain of the 3-D view can lead to erroneous conclusions about the relative sizes, positions and convergence of structures within a specimen. In addition, Walter has suggested that the stereo image contains information equivalent to a two-fold increase in magnification over that found in a 2-D image. Because of these factors, stereo pair analysis should be routinely employed when studying specimens.Imaging complementary faces of a fractured specimen is a second method by which the topography of a specimen can be more accurately evaluated.

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Histological evaluation of cochlear hair cell damage from noise-induced hearing loss in chinchillas

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100159217 ◽

1990 ◽

Vol 48 (3) ◽

pp. 332-333

Author(s):

R.V. Harrison ◽

R.J. Mount ◽

P. White ◽

N. Fukushima

Keyword(s):

Hair Cell ◽

Evoked Potential ◽

Cell Damage ◽

Acoustic Trauma ◽

Histological Evaluation ◽

Cell Integrity ◽

Functional Changes ◽

Cochlear Hair Cell ◽

Left And Right ◽

Contralateral Ear

In studies which attempt to define the influence of various factors on recovery of hair cell integrity after acoustic trauma, an experimental and a control ear which initially have equal degrees of damage are required. With in a group of animals receiving an identical level of acoustic trauma there is more symmetry between the ears of each individual, in respect to function, than between animals. Figure 1 illustrates this, left and right cochlear evoked potential (CAP) audiograms are shown for two chinchillas receiving identical trauma. For this reason the contralateral ear is used as control.To compliment such functional evaluations we have devised a scoring system, based on the condition of hair cell stereocilia as revealed by scanning electron microscopy, which permits total stereociliar damage to be expressed numerically. This quantification permits correlation of the degree of structural pathology with functional changes. In this paper wereport experiments to verify the symmetry of stereociliar integrity between two ears, both for normal (non-exposed) animals and chinchillas in which each ear has received identical noise trauma.

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The crystallography characteristic of (Mn,Fe)S single crystal

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100177623 ◽

1990 ◽

Vol 48 (4) ◽

pp. 898-899

Author(s):

Jiang Xishan

Keyword(s):

Single Crystal ◽

Cast Steel ◽

Point Group ◽

Central Area ◽

Hexagonal Crystal ◽

Growth Step ◽

Left And Right ◽

Relationship Of ◽

Fcc Structure ◽

New Discovery

This paper reports the growth step pattern and morphology at equilibrium and growth states of (Mn,Fe)S single crystal on the wall of micro-voids in ZG25 cast steel by using scanning electron microscope. Seldom report was presented on the growth morphology and steppattern of (Mn,Fe)S single crystal.Fig.1 shows the front half of the polyhedron of(Mn,Fe)S single crystal,its central area being the square crystal plane,the two pairs of hexagons symmetrically located in the high and low, the left and right with a certain, angle to the square crystal plane.According to the symmetrical relationship of crystal, it was defined that the (Mn,Fe)S single crystal at equilibrium state is tetrakaidecahedron consisted of eight hexagonal crystal planes and six square crystal planes. The macroscopic symmetry elements of the tetrakaidecahedron correpond to Oh—n3m symmetry class of fcc structure,in which the hexagonal crystal planes are the { 111 } crystal planes group,square crystal plaits are the { 100 } crystal planes group. This new discovery of the (Mn,Fe)S single crystal provides a typical example of the point group of Oh—n3m.

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