Aluminum block

Electrical heating is accomplished with resistance bauds or ribbons which must be electrically insulated from the machine body but in good thermal contact with it. The heaters must be carefully spaced to avoid a succession of hot and cold areas. Sometimes they are mounted in aluminum blocks shaped to conform to the container walls. Their effective temperature range is 150 to 500°C (about 300 to 930°F). Temperature control is precise, maintenance and supervision costs are low, and conversion of electrical energy to useful heat is almost 100 percent. The cost of electrical energy is usually large, however, and may be prohibitive. 

A schematic view of an extruder is shown in figure 1. The extruder barrel is essentially a ferrous alloy cylinder, with aluminum block heaters attached to the outside. There are several temperature control zones along the length of the extruder. Measurement thermocouples are installed in the extruder barrel itself. Barrel temperature is used to control the temperature of the polymer melt. Energy from the heaters is conducted both radially and axially in the barrel. Below, figure 2 shows a sketch of the extruder barrel, with the heaters and the temperature measurement points used in this paper marked. 

The trin r samples were polyn rized in sealed pyrex ampoules placed in an aluminum block oven at 250 C. Typically, the ampoules contained 50g of trimer sealed under vacuum (0.005 to 0.010 mm Hg) and the reactions were terminated by removing the ampoules from the oven. After cooling, the ampoules were opened and the contents removed. 

The palladium-catalyzed asymmetric allylic substitution using seven different phosphano-oxazoline ligands at various ligand-to-metal ratios was also studied.112 An aluminum block containing 27 wells was placed in a dry box in which the reactions were carried out in parallel. Analyses were performed by conventional chiral GC equipped with an autosampler. Such a setup allowed about 33 catalyst evaluations per day. Apparently, only a few dozen were carried out in the study, resulting in the identification of a catalyst showing an ee-value of 74% in the reaction of 4-acyloxy-2-pentene with malonate.112 It is not clear whether further ligand diversification would lead to catalysts more selective than the record set in this case by the Trost-catalyst (92% ee).113... 

Magnesium, zinc, or aluminum blocks are anached to ships hulls, oil and gas pipelines, underground iron pipes, and gasoline storage tanks. These reactive metals provide cathodic protection by acting as a sacrificial anode. 

Fig. 1.41. Micropositioning assembly in the MIM tunneling experiment. In an aluminum block (1), two gold electrode.s (2) are contained. The right electrode is attached to a pair of membranes (3), and actuated by a stack of piezoelectric plates (4). The left electrode is actuated by a differential screw (5) for coarse positioning. The entire assembly is enclosed in a thermostat and then a vacuum chamber. (After Teague, 1978.)...

The reaction mixtures are cooled by placing the 96-well PGR plate on top of a 96-well aluminum block chilled on ice. Heat-shock of 42°C is accomplished by placing the plate in a water bath. Recooling on ice is done first by placing the plate in an ice-water bath and then by placing the plate on top of a 96-well aluminum block chilled on ice. 

Kreulen s Aluminum Block. See Aluminum Block (of Kreulen) in Vol 1, p A145-L... 

To control the area of the sample which was exposed to the beam, a thick aluminum block with a %-inch diameter aperture in the center was constructed and placed directly in front of the sample. 

The beam current to which the sample is exposed—i.e.9 the current which passes through the %-inch diameter aperture in the aluminum block—is in turn captured by another block behind the sample. The amount of the current received by this second block is used as a primary measure of the radiation intensity (beam current). This second block or plate is supported behind the sample on two ceramic insulators and is easily removed to facilitate changing samples. 

The samples were irradiated with 60Co gamma rays in an AECL Gammacell or in the pond facility of the AAEC, at dose rates from 0.1 to 2 Mrad h-1, to total doses from 0.1 to several hundred Mrad. Constant temperatures from 77° to 448°K (-196° to 175°C) were maintained using liquid nitrogen, slush baths, solid C02 and aluminum block heaters. 

Aluminum Block Expansion Test is similar to the Lead Block Expansion Test,but superior to it when testing brisant expls, especially those contg Al. A brief description of this test is given under Trauzl Tests Aluminum Boride. See under Borides... 

The output test using an aluminum block is performed in accordance with Test 303 of MIL-STD-331A. This test is identical in all respects with the steel dent test except that dent block is made of aluminum. Substitution of the softer metal allows testing of components whose output is insufficient to dent steel. ]... 

Aluminum Azide. See under Azides, Inorganic Aluminum Block (of Kreulen) is a hollow Al block used for detg the tendency of coal and other materials to spontaneous combustion... 

KI-Starch Test. See Abel s Test A2-L Kreulen, Aluminum Block of A145 L... 

Aluminum block Durham tube 96 Deep well B 7 mm, L 40 mm microplale... 

The reactor was heated by resistance wires wound in massive aluminum blocks placed around the reactor. The reactor temperature was measured at every inch of the catalyst height by traversing a thermocouple in a thermowell placed along the reactor bed. The reactor was operated at nearly isothermal conditions (1.5C° radial differences). 

Because a variety of individual holes may be drilled into a single aluminum block, it is possible to easily rotate different-sized flasks on a random basis with ease and have separate holes for thermometers as well. The thermometer allows you to easily monitor temperatures for various thermostat settings. By graphing these temperatures settings, one can easily set a temperature on a Variac as easily as setting a temperature on a stove. 

Filler at 100 pph Phenolic laminate tested at Aluminum block tested at ... 

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