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Flame sampling apparatus

Techniques have been developed for the quantification of fire propagation using FMRC s Small-Scale Flammability Apparatus (A,6) and the National Institute of Standards and Technology (NIST) Flame Spread Apparatus (j J ). In this study, the FMRC technique was used. Oxygen Index and its dependency on temperature was used by AMTL to examine the fire propagation behavior of small samples of FRC materials (J 2). [Pg.543]

Polymerization of I. Polymerizations were carried out in flame-dried apparatus under a N2 atmosphere. A 50-mL round-bottom flask equipped with a poly(tetra-fluoroethylene) (Teflon)-covered magnetic stirring bar and a rubber septum was charged with I (6 g, 36 mmol) dissolved in 30 mL of hexane. n-Butyllithium (0.1 mL, 1.5 N) was added to this mixture at room temperature. The reaction was stirred for 60 h. Ether was then added, and the organic phase was washed twice with water, dried over anhydrous magnesium sulfate, and filtered. The solvent was removed by evaporation under reduced pressure. The residue was taken up in THE, and the polymer product, a viscous oil, was precipitated by addition of methanol. The THF-methanol supernatant liquid was decanted from the polymer it contained 2.0 g of I. This precipitation procedure was repeated to obtain analytical samples. The polymer was dried at 57 °C under vacuum overnight, and 3.7 g (93% yield) was obtained. [Pg.688]

Procedure. The sample, mixed with very pure quartz sand or silica powder, is placed in the bulb of the apparatus and moistened thoroughly with 1 or 2 drops of concentrated sulfuric acid. The stopper, with its suspended water drop, is put in place and the apparatus gently heated for about 1 minute. After removing the flame, the apparatus is allowed to stand 3-5 minutes. The water drop is then washed into a micro crucible, 1 or 2 drops of ammonium molybdate added, and the mixture warmed until bubbles begin to rise. When... [Pg.226]

The liquid becomes progressively darker in colour, and then effervesces gently as ethylene is evolved. Allow the gas to escape from the delivery-tube in T for several minutes in order to sweep out the air in F and B. Now fill a test-tube with water, close it with the finger, and invert the tube in the water in T over the delivery-tube so that a sample of the gas collects in the tube. Close the tube again with the finger, and then light the gas at a Bunsen burner at a safe distance from the apparatus. If the tube contains pure ethylene, the latter burns with a clear pale blue (almost invisible) flame if the ethylene still contains air, the mixture in the test-tube ignites with a sharp report. Allow the... [Pg.84]

In the Wickbold method, solid samples are vaporised in an oxygen stream and fed into an oxyhydrogen flame, which bums in a cooled quartz tube. The combustion products are condensed here, or are captured in an absorption solution as gaseous materials. Although combustion in a Wickbold apparatus is a quick and effective method for destroying organic material of all types, incomplete destruction may occur [19]. In special digestion vessels, known as cold-plasma ashers (CPA),... [Pg.593]

This contains two ignitability tests one uses a glowing wire and one a needle flame. Setchkin ignition apparatus. Measures flash ignition and spontaneous ignition temperatures. Normal sample orientation horizontal. [Pg.467]

Commonly used methods for the determination of petroleum hydrocarbon contamination in soil are modifications of Environmental Protection Agency method 418.1, which use sonication or a Soxhlet apparatus for analyte extraction and either infrared spectrometry [5] or gas chromatography with flame ionization detection [6-7] for extract analysis. Regardless of the analytical method following the extraction, both modifications use Freon-113, which has been implicated as a cause of ozone depletion. Therefore, alternative methods are being sought for the determination of hydrocarbon contamination in environmental samples that reduce the need for this halogenated solvent. [Pg.119]

The aim of the present work was to design and operate an apparatus in which stationary combustion and flames can be produced and sustained to pressures of 2000 bar and with environmental temperatures up to 500°C. Visual observation of the interior of the reaction vessel should be possible. Arrangements had to be made by which a gas flow of only a few microlitres per second could be fed steadily into the reaction vessel at pressures to two kilobar. A similar provision was necessary to extract small samples for product analysis at constant conditions. The principle of design and operation will be described. First results will be given for experiments with oxygen introduced into supercritical water-methane mixtures. [Pg.2]

Fig. 9.4.10 Apparatus for the gas flow-arc plasma method. The apparatus is composed of two components. The upper part is a glass Dewar, which accumulates small particles in a cryogenic matrix on the trim cooled with liquid nitrogen (LN). Sorv, inlet of organic vapor Syr, syringe for transferring produced colloids under anaerobic conditions RP, rotary pump S, target sample. Lower part is for plasma discharge. A BN furnace has gas inlets (G) and is specially designed for Ar gas to flow in screwed stream hence the plasma is emitted in a jet flame due to a plasma pinch effect. The black parts are copper electrodes cooled by water. In order to maintain a constant spacing between the surface of sample and tbe upper electrode, the sample position can move vertically so that the current through the sample to the upper electrode is precisely controlled and constant. This is very important to produce powders with a narrow size distribution. Fig. 9.4.10 Apparatus for the gas flow-arc plasma method. The apparatus is composed of two components. The upper part is a glass Dewar, which accumulates small particles in a cryogenic matrix on the trim cooled with liquid nitrogen (LN). Sorv, inlet of organic vapor Syr, syringe for transferring produced colloids under anaerobic conditions RP, rotary pump S, target sample. Lower part is for plasma discharge. A BN furnace has gas inlets (G) and is specially designed for Ar gas to flow in screwed stream hence the plasma is emitted in a jet flame due to a plasma pinch effect. The black parts are copper electrodes cooled by water. In order to maintain a constant spacing between the surface of sample and tbe upper electrode, the sample position can move vertically so that the current through the sample to the upper electrode is precisely controlled and constant. This is very important to produce powders with a narrow size distribution.
Sampling and Analysis. A frozen slice of bread was cut in pieces and stacked in an enlarged sample flask of an aroma isolation apparatus according to MacLeod and Ames (74). Volatile compounds were trapped on Tenax TA and afterwards thermally desorbed and cold trap injected in a Carlo Erba GC 6000 vega equipped with a Supelcowax 10 capillary column (60 m x 0.25 mm i.d.) and a flame ionisation detector. Similar GC conditions were used for GC-MS identification of volatile compounds by dr. M.A. Posthumus (Dept. Organic Chemistry, VG MM7070F mass spectrometer at 70 eV El, 75). [Pg.194]

What had happened to this sample to yield such unexpected results The purity of the starting monomer, other than its water content, was probably no better or worse than that used in previous studies. The final degassing of the monomer had been conventional. Only one difference had been introduced in the preparative scheme—the monomer had been dried over baked silica gel, and the glassware of the vacuum apparatus had been flame-dried under vacuum. In other words, the irradiated styrene had been exhaustively dried. [Pg.182]

A sample of approximately 15 to 20 ml. of monomer was collected in an ampoule (A, Figures 1 and 2), attached to the product take-off assembly of the still. There are no stopcocks between the column and vessel A, and hence no possibility of contamination with any stopcock lubricant. When sample collection is completed, the ampoule is isolated from the distillation apparatus by freezing a monomer-filled U-tube located between the distillation head and the collection vessel. The contents of the ampoule are then frozen, and vessel A is removed from the still by flame-sealing at point 1. The monomer in vessel A is kept frozen until the degassing step is reached. [Pg.183]

BM Apparatus, 1kg wt 30 cm with 20 mg sample (Phillips gave 68 cm with 2 kg wt) Initiating Efficiency 0.4 g of LNDR did not initiate Tetryl pressed at 3000 psi Minimum Detonating Charge of MF - 0.24 g Sensitivity to Flame -deflagrates Sensitivity to Spit of BkPdr Fuse -deflagrates Vacuum Stability at 1200 - exploded in 73 mins... [Pg.169]

Fig. 9.2. Constant-volume tensimeter. The sample tube (enlarged view, upper left) is loaded with solid in a dry box or by sublimation from the vacuum line. The lube is evacuated, sealed, weighed, then glassblown to the tensimeter. After evacuating and flame-drying the tensimeter, the mercury level is raised and the break-seal cracked. Since the mercury serves as the cutoff to the vacuum manifold, the sample is not exposed to grease, stopcocks, or joints. This design is desirable when very long equilibration times are necessary. The mercury level is adjusted at the volume-calibrated reference point, such as A on (he diagram, if it is important to know the gas volume in the apparatus. Fig. 9.2. Constant-volume tensimeter. The sample tube (enlarged view, upper left) is loaded with solid in a dry box or by sublimation from the vacuum line. The lube is evacuated, sealed, weighed, then glassblown to the tensimeter. After evacuating and flame-drying the tensimeter, the mercury level is raised and the break-seal cracked. Since the mercury serves as the cutoff to the vacuum manifold, the sample is not exposed to grease, stopcocks, or joints. This design is desirable when very long equilibration times are necessary. The mercury level is adjusted at the volume-calibrated reference point, such as A on (he diagram, if it is important to know the gas volume in the apparatus.
Arsenic.—50 grams of the minced sample are weighed into a round-bottomed flask and heated over a naked flame with 10 c.c. of concentrated sulphuric acid when the mass becomes dense, 30 c.c. of the same acid are added, the heating being continued and further small quantities of acid added until the liquid is completely decolorised. When cold, the solution is poured carefully into 150 c.c. of cold water, the resulting liquid being filtered and the filtrate tested for arsenic in the Marsh apparatus see later, 5, b) and also for any other metals (zinc, nickel, etc.). [Pg.18]

Pensky-Martens dosed tester-apparatus used in determining the flash point of fuel oils and cutback asphalt, under conditions prescribed by test method ASTM D 93. The test sample is slowly heated in a closed cup, at a specified constant rate, with continual stirring. A small flame is introduced into the cup at specified... [Pg.197]

Tag open cup-apparatus for determining the flash point of hydrocarbon liquids, usually solvents, having flash points between -17.8° and 168°C (0° to 325°F), under test methods prescribed in ASTM D 1310. The test sample is heated in an open cup at a slow, constant rate. A small flame is passed over the cup at specified intervals. The lowest temperature at which the vapors above the sample briefly ignite is the flash point. See Cleveland open cup. [Pg.221]

The carboxin is extracted from the sample with acetone in a Soxhlet extraction apparatus and, after concentration of the extract, is determined via gas-liquid chromatography using a nitrogen-selective detector. The presence of carboxin is confirmed by the use of a sulfur flame photometric detector. Recoveries ranged from 73 to 80% (barley) and 73 to 78% (wheat). [Pg.241]

The Lateral Ignition and Flame spread Test (LIFT) apparatus was developed primarily for lateral flame spread measurements. The apparatus, test procedures, and methods for data analysis are described in ASTM E 1321. A sample of 155 x 800 mm is exposed to the radiant heat of a gas-tired panel. The panel measures 280 x 483 mm. The heat flux is not uniform over the specimen, but varies along the long axis as a function of distance from the hot end as shown in Figure 14.6. The flux distribution is an invariant of distance when normalized to the heat flux at the 50 mm position. When methane or natural gas is burnt, the upper limit of the radiant heat flux is 60-65 kW/m2. The lower limit is approximately 10kW/m2 since the porous ceramic tile surface of the panel is only partly covered with flame at lower heat fluxes. [Pg.361]

The heat flux distribution is fairly uniform over the first 100-150mm. Therefore, the same apparatus, with some slight modifications, may also be used for ignitability measurements. A 155 x 155mm specimen is positioned at the hot end in the flame spread sample holder. An acetylene-air pilot is located... [Pg.361]


See other pages where Flame sampling apparatus is mentioned: [Pg.188]    [Pg.154]    [Pg.154]    [Pg.86]    [Pg.101]    [Pg.106]    [Pg.149]    [Pg.440]    [Pg.317]    [Pg.72]    [Pg.479]    [Pg.278]    [Pg.71]    [Pg.612]    [Pg.168]    [Pg.467]    [Pg.525]    [Pg.547]    [Pg.265]    [Pg.243]    [Pg.87]    [Pg.624]    [Pg.588]    [Pg.99]    [Pg.487]    [Pg.488]    [Pg.194]    [Pg.146]    [Pg.154]    [Pg.75]   
See also in sourсe #XX -- [ Pg.4 , Pg.7 ]




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Flames sampling

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