Dextrins thickness

The mixture can be made into beads. To do this, add to it thick starch size or a solution of dextrin in cold water until a thick dough is formed. Make beads 5 mm in diameter from it. Put the beads on a chamotte plate and dry them in a drying cabinet at a temperature of 100 °C. 

Preparation of Anhydrous Chromium(III) Chloride. Perform the experiment in a fume cupboard Grind 5 g of charcoal into a fine powder in a mortar, mix it with 12.5 g of chromium(III) oxide, add a thick starch size or a dextrin solution in cold water, and make beads about 5 mm in diameter from the mixture. Put the beads onto a clay dish and dry them in a drying cabinet at 110-120 °C. Next put them into an iron crucible, cover them with the charcoal powder and a lid, and roast them. 

Fig. I. Single-drum dryer (atmospheric). Dryers of this type may be dip or splash fed (not shown), or, as shown, equipped with applicator rolls. The latter is particularly effective for drying high-viscosity liquids or pasty materials, such as mashed potatoes, applesauce, fruit-starch mixtures, gelatin, dextrine-type adhesives, and various star dies. The applicator rolls eliminate void areas, permit drying between successive layers of fresh material and (omi me product sheet gradually. While single applications may dry to a lacy sheet or flakes, the multiple layers generally result in a product of uniform thickness and density with minimum dusting tendencies. (Bujiovak Division, BlawKnox Food Chemical Equipment. Inc)...

No essential difference was found under the experimental conditions between the layer thickness for Newtonian and non-Newtonian liquids, as may be judged from a few data available on non-Newtonian liquids (e.g., latex SKS-30L and dextrin glue). This non-trivial experimental result has not yet been convingly or reasonably explained. 

This results from the transformation of starch by means of heat or by the action of dilute acid or diastase. It is prepared principally from potato, wheat or maize starch and rarely from rice or other exotic starches. Many varieties of dextrin, made in diverse ways, are sold under different names. It occurs as a fine powder, either wliite, dirty white, yellowish or light brown as granules, similar in appearance to gum arabic and as a thick syrup, more or less highly coloured and opaque. In general dextrin has a special odour and taste, which are particularly marked in the pulverulent varieties. It is soluble in water, but insoluble in alcohol. Its solution is strongly dextro-rotatory the value of [a]D varies from 173° to 2250,but is mostly about 200°. With iodine different dextrins give bluish violet to brownish red colorations (the colour is observed by adding the iodine solution drop by drop if the mass is mixed after the first drops are added, the colour disappears). 

A series of pulsed electron beam tests were conducted on dextrinated and RD-1333 Pb azide pellets by Avrami et al (Ref 232), From the limited data in Table 14 it can be seen that sample ambient pressure, sample thickness and type of Pb azide are all important factors in the sensitivity of initiation by pulsed electron beam The question arises as to what mechanism can explain the observed pressure, thickness and type of Pb azide dependence. A purely thermal initiation mechanism or a compressive shock initiation resulting from nearly instantaneous energy deposition can account for some of the observations but not all... 

A source of commercial glucose. Starch from various sources, e.g. corn, potatoes, etc., is hydrolyzed by boiling with dilute sulphuric acid, by which the final hydrolytic product, glucose, is obtained. It is ordinarily obtained as a thick syrup, corn syrup, or as a crystalline substance, glucose. Corn syrup as usually made is not pure glucose syrup but contains more or less of the intermediate products, dextrin and maltose. With these present the syrup does not crystallize even when very concentrated. 

The black antimony sulfide and the potassium chlorate are both wet before being mixed. If they are mixed dry an explosion can result. Then add dextrine or glue and enough water to make a thick paste. 

For a better quality powder, add one-half pan of dextrine or one part Lepage s Mucilage and enough water to form a thick mush. Stir and mix well and then rub it through a window screen in a thin layer on waxed paper. A lot will stick to the bottom of the screen. Let this dry until it can be scraped off without the particles going back to mush or being so dry as to become powder. 

The effect of an electric field on dextrinated lead azide pellets as a function of density and thickness was also studied [11]. The explosive was pressed in a nylon sleeve between two 0.48-mm (0.187-in) -diam, flat-surface steel rods with rounded edges. The explosive was subjected to a one-minute-on, onc-minutc-off application of voltage, increasing the voltage in 100-V increments until the sample detonated. The current was monitored continuously. 

Figure 19. Average electric field strength for detonation of dextrinated lead azide as a function of thickness [11].

Tests on dextrinated and RD 1333 lead azide (Table XVII) showed that ambient pressure, sample thickness, and the type of lead azide are important factors in determining the sensitivity to pulsed electron beams [107]. 

The samples were free standing disks of pressed dextrinated lead azide, pressed at 40,000 psi and having densities of 3.18-3.41 g/ml, depending on the thickness of the disks. 

The threshold for the detection of reaction in the dextrinated lead azide (3.4 g/ml) subjected to 3,5-psec pulses was dependent upon sample thickness (Figure 25). No reaction was noted in 1-mm-thick samples even at the highest impact stresses (8.9 kbar) tested, whereas the threshold for 4-mm-thick samples was between 4 and 6 kbar. 

The lead azide targets (Figure 27) were pressed into lead sleeves in an aluminum cup to a nominal thickness of 2 mm with an average density of 3.6 g/ml for the PVA material and 2.95 g/ml for the dextrinated azide. The experiments were conducted at ambient temperatures and a pressure of less than 5 pm mercury. 

Comparison of initiation-threshold measurements suggests that there is a minimum thickness, or a run-up distance, before detonation occurs and that this is independent of pulse-width for stresses up to 10 kbars. For long pulses (3.5 psec) in the gas gun, no evidence of detonation was detected for 1-mm-fhick samples. Detonation occurred with run-up distances in the range of 1-2 mm for impact stresses of 8.9 kbar. For stresses greater than 6.0 kbar, evidence of detonation was noted after a 2-mm run. In the thin-flyer-plate experiments at stresses of 8 kbar, dextrinated lead azide displayed a 2-usec initiation delay. Voreck and coworkers [8] determined that a similar minimum thickness of lead azide is required for complete detonation in an explosive train consisting of NOL-130, lead azide, and RDX (Figure 15). 

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