Hollow powder

Guo HB, Kuroda S, Murakami H. Segmented thermal barrier coatings produced by atmospheric plasma spraying hollow powders. Thin Solid Films. 2006 506-507 136-139. 

To clear up a role of two-side filling with liquids of dead-end capillaries in the practice of PT, we ve carried out some special experiments. It was established some years ago that it s almost impossible to reveal small defects applying dry powder developer in the case when defect s hollows are completely filled with a penetrant. But just such a situation one... 

The most widely used development in HTS wire production is tlie powder-in-tube procedure with BSCCO ceramic materials. In this procedure very fine HTS powder, placed inside of a hollow silver tube, is fused as the tube lengtn is mechanically increased to form a wire. Very high magnetic fields with this wire have been reported at 4 K however, the performance degrades substantially above 20 to 30 K. 

Nonbiological methods for removal of trichloroethylene from water are also being studied. These include the use of a hollow fiber membrane contactor (Dr. A.K. Zander, Clarkson University), photocatalysis by solar or artificially irradiated semiconductor powders (Dr. G. Cooper, Photo-catalytics, Inc.), and micellar-enhanced ultrafiltration (Dr. B.L. Roberts, Surfactant Associates, Inc.). 

One of the most widely used spray-drying techniques for coffee extract involves spraying percolated coffee extract at 40°F into the top of a baffled tower of hot air at 480°F initially. The cooler wet air is removed toward the bottom of the tower and finally a powder of the coffee extract solids leaves the tower at about 90°F. These solids are in the form of hollow beads and contain 3% moisture. 

Slurry containing the cathode powder is placed into a cylindrically shaped die with an open end, as shown in Figure 6.7 (a), and then a mandril is inserted into the tube that extrudes the slurry into the shape of a hollow tube with a closed end on one side and an open end on the other side, as shown in Figure 6.7 (b). The electrolyte, anode, and interconnect layers are then deposited onto the cathode support tube, using combinations of processes described in Section 6.2.2. 

Pigment powders continue to be used in thick-walled articles, such as extruded sheets, or hollow objects, or in injection-molded products although color concentrates are beginning to be more important even in these areas. 

With the introduction (about the end of the 15th century) of hollow type projectiles charged with Black Powder, these shells also became, to a certain extent, incendiary missiles. This was due to the fact that, when such a shell burst, the flame produced by the explosion of the Black Powder could ignite any closely-located inflammable object... 

Shock tube Hollow plastic tube with a thin coating of HMX and powdered aluminum used in nonelectric firing systems. 

One popular configuration is the Grimm source, which accepts samples in the form of discs. Such sources usually operate at 500-1000 V, 25-100 mA and 1-5 Torr, wiA detection limits of approximately 0.1 ppm. Another configuration is the hollow-cathode lamp in which the sample can be either machined as a hollow cathode, evaporated to dryness (if a solution) or pressed (if a powder) into a hollow cathode made of pure graphite. Typical operating conditions are 200-500 V, 10-100 mA, and 0.1-1.0 Torr, with detection limits in the range 0.1-10 ppm. 

Using a similar procedure, it was also possible to coat cationic and anionic latexes with zirconium hydrous oxide (145). On careful heating such powders in air at temperatures >500°C the core polymer was vaporized and the shell was calcined to yield hollow spheres of Zr02, as illustrated in Figure I.1.21B (145). 

EXE Powder. Brit brown powder used for a while after 1876 in cannons of 152mm as a replacement for BkWr, known as P (Pebble) Powder, which was in the form of cubes. EXE Powder was in the form of prisms with one central canal and with one of its bases being hollow and with grooves Ref Daniel (1902), 287 8c 595... 

One type of machine employs a dosator. The dosator can be viewed as a hollow tube containing a moveable piston (Fig. 1). The piston is preset to a particular height in the tube so that the volume between the piston head and the open end of the dosator would contain the appropriate mass of the formulation. In operation, the open end of the dosator is plunged downward into a powder bed that had been struck-off neatly at a particular height. 

Preparation of Chromium. Perform the experiment in the presence of your instructor, in a fume cupboard Wear eye protection or a mask ) Roast chromium(III) oxide in an iron crucible. Triturate potassium dichromate crystals in a mortar, melt the powder in a porcelain crucible with the flame of a gas burner, pour the substance onto a glazed tile plate, and after it solidifies again triturate it into a powder. Weigh 12 g of roasted chromium(III) oxide, 12 g of the fused potassium dichromate, and 10 g of an aluminium powder, and thoroughly mix all the substances in a mortar. Spill 10 g of a calcium fluoride powder onto the bottom of a chamotte crucible, and then the prepared mixture. (If there is no chamotte crucible in your laboratory, make a box from asbestos paper in the form of a crucible and fasten it with wire.) Tamp the substance with a pestle and make a hollow in the middle using a test tube (see Fig. 120). 

Prepare an incendiary mixture by shaking 5 g of an aluminium powder and 15 g of barium peroxide in a jar. (2 o not triturate the mixture in a mortar ) Spill the incendiary mixture into the hollow made in the reaction mass and insert a magnesium ribbon cleaned of oxide. Place the crucible on a pan and spill dry sand over it from all sides. Ignite the magnesium ribbon with a burning splinter insert-... 

Core Explosives or Core Charges. In ordet to lower the temperature of explosion to the level of "permissible explosives, thus avoiding the ignition of firedamp and dust in coal mines, R.W. Lawrence of Hercules Powder Co proposed [USP 2565380(1951) CA 46, 1752(1952)] to place inside of an AN Dynamite cartridge a "core , which can be either hollow or consist of an "inert material, similar to that used for sheaths (See under Enveloped or Sheathed Explosives)... 

Ejecting Projectiles (Ger). Special projectiles which ejected incendiary missiles on approaching a target (such as an airplane) were developed during WWII at Krummel Fabrik of Dynamit AG but did not come to the manufacturing stage. These projs contd several hollow steel cylinders, each of which was filled with an incendiary mixture consisting of Ba peroxide, powdered A1 and Fe. 

Powder C had particles with more and deeper folds or shrinkages and had frequently, as shown in Figure 5, broken hollow particles,possibly due to ballooning effect, as compared to powders A and B. The observed change is further magnified (1800 x) in Figure 4. 

---