Aluminum supports

The secret that makes this process work is no surprise, the catalyst. Those that work include some of the noble metals, specifically, platinum or palladium, a rare earth metal like cerium or neodynium (are they rare or what ) on alumina, or a non-noble metal like chromium on a silica-aluminum support. 

Our initial work on the TEMPO / Mg(N03)2 / NBS system was inspired by the work reported by Yamaguchi and Mizuno (20) on the aerobic oxidation of the alcohols over aluminum supported ruthenium catalyst and by our own work on a highly efficient TEMP0-[Fe(N03)2/ bipyridine] / KBr system, reported earlier (22). On the basis of these two systems, we reasoned that a supported ruthenium catalyst combined with either TEMPO alone or promoted by some less elaborate nitrate and bromide source would produce a more powerful and partially recyclable catalyst composition. The initial screening was done using hexan-l-ol as a model substrate with MeO-TEMPO as a catalyst (T.lmol %) and 5%Ru/C as a co-catalyst (0.3 mol% Ru) in acetic acid solvent. As shown in Table 1, the binary composition under the standard test conditions did not show any activity (entry 1). When either N-bromosuccinimide (NBS) or Mg(N03)2 (MNT) was added, a moderate increase in the rate of oxidation was seen especially with the addition of MNT (entries 2 and 3). 

It is, however, more complex than this because the silica-alumina support affects also the polymerization. A. Clark describes the correlation between the chromium trioxide and the silica-aluminum support. He also shows the effect of the catalyst activation temperature on the molecular weight of the polyethylene formed. 

The catalyst may be prepared by impregnating a silica-aluminum support with an aqueous solution of chromium trioxide. After drying, the catalyst is usually activated in a stream of dry air at temperatures ranging from ca. 400°-800°C. Under these conditions catalysts can be prepared with a major percentage of chromium in the form of chromium trioxide. Evidently, the support is not just an inert diluent for chromium oxide by itself is stable only as Cr203 at these temperatures. There must be interaction between chromium trioxide and the support which stabilizes the former. 

The metallic layers were examined either by conventional or cross-section TEM in a Jeol 200 Cx microscope. For the cross section preparation a sandwich of two laminates is made, glued face to face with an epoxy, cut in small pieces, mechanically polished, and then ion milled to a final TEM observation thickness. The plane section TEM sample are prepared by dissolving the PET in trifluoroacetic acid for 5 to 10 mn. The area observed, on plane section TEM, for the grain size calculation is close to 0.2 urn. For the adhesion measurements, test pieces consist of aluminum support (1 mm thick) double sided tape (Permacel P-94) PET (12pm) / evaporated aluminum/ ethylene acrylic acid (EAA) copolymer film. These laminates are prepared for the peel test by compression under 1.3 105 N.m2 at 120°C for 10 seconds. The peel test is performed by peeling the EAA copolymer sheet from the laminate in an INSTRON tensile tester at 180° peel angle and 5 cm min peel rate. 

The glass tube is fixed on a stand by an aluminum support frame. A glass rod is used to fix the distanee between the eleetrodes, as they may be pulled each other and attract together under the strong magnetic field, if a cold-rolled steel (CRS) panel is used as the cathode. The gas is fed through a small hole placed in the center of the anode. The cathode is made of a 7 x 7 in CRS plate. The ratio of cathode surface area to anode surface area is 4.5 1. 

In order to confirm that the film thicknesses monitored on quartz were the same as those on aluminum under identical coating conditions, the following experiment was performed. Sample films on aluminum, 10 cm2, were obtained for each polymer under coating conditions established on quartz. The polymer films were dissolved off the aluminum support with methylene chloride into 10 mL volumetric flasks. The... 

The polymer films on the aluminum support were exposed in the same manner as described for the films on quartz. However, in addition the films were irradiated through a photographic step tablet in which the density varies in increments of 0.15 per step. After irradiation, the films were developed by soaking in cyclohexanone for one minute or until no further change was noted in the number of crosslinked polymer steps. 

The detectors were made from pure (Series 1100) aluminum plates with a coated area of 3 X 20 mm. They were arranged cylindrically with their long dimension vertical about the line of intersection of the two vertical ribbon beams. The detectors were equally spaced (except for beam entrances and exits) and mounted on two aluminum support rings that formed the edges of a... 

The liquid photosensitive resin is employed as a top coating on an aluminum support. A negative is then used and exposed to actinic radiation from a Xenon lamp. The unexposed areas are removed with a solution of surface-active agents using an ultrasonic washing technique. 

Solid photopolymer plates for printing were pioneered by Dupont with the introduction of Dycril in 1957. The photosensitive layer in Dycril is a 0.3-1.0mm thick binder composed of a water-soluble cellulose derivative such as cellulose acetate succinate, a monomer of the divinyl type such as triethylene glycol diacrylate, and a photo-initiator such as 2-ethylanthraquinone and a thermal stabilizer (inhibitor) of the p-methoxyphenol type. The mixture is applied on an aluminum support or steel with an adhesive sheet and exposure to actinic radiation from a carbon or mercury arc lamp is performed through a negative placed over the photosensitive layer. Postexposure treatment involves washing with a 0.2-0.5% caustic soda solution that removes the unexposed area and leaves a relief on the support. Dycril is fairly cheap, has a fairly high resolving power, and is durable. 

Figure 1 Parts of a pervaporation module (A) acceptor chamber (B) membrane support (C) spacer (D) donor chamber (E) aluminum supports (F) and (G) rods for screwing and aligning the module, respectively (H) connectors (I) screws. (Reprinted with permission from De Mattos et al. (1995) Pervaporation an integrated. Talanta, 42 757 Elsevier.)...

Ota, X. Aluminum support for presensitized lithographic printing plate showing excellent sensitivity, printing-resistance, smear-resistance, and plate-cleanability and image formation method with 350-450 nm laser light. Jpn. Kokai Xokkyo Koho IP 2004358780, 2004 Chem. Abstr. 2004,142, 82321. 

Pulsed reactivity measurements were made, in the Subcritical Eiqperiment Facility at the vannah River Laboratory. A rigid aluminum support frame maintained accurate spacing within the arrays. The lattices were tolly flooded to achieve an effective infinite H2O reflection. A KAMAN modei A-800 puised-neutron generator was located at the mhtotone 15 cm from toe core. Neutron detectors were placed in the low importance region on toe radial centerline of representative fuel assemblies. The measured fundamental-mode prompt-neutron decay constant, (meas), was determined by standard pulsedineutron techniques (Table I). 

HPTLC prepared plates are mostly available on glass in 10 x 20 cm, 10 x 10 cm, and 5 X 5 cm sizes because of the shorter developing distances required. A couple, however, are available with the aluminum support (often called an aluminum foil). These are 5 X 7.5 cm in size and are used in MS techniques as described previously. One such paper by Himmelsback et al. [3] used the HPTLC silica gel on aluminum to separate various mixtures, cut the plate with a 60° angle point in front of the band, placing it in front of the MS orifice, and a spectra was obtained after a spray solvent was applied to the thin layer. 

In the case of combining DESI ion source with TLC separation technique for its analysis, it is advisable to use good quality TLC plates. During the ionization process, the stationary phase might be detached from the plate surface and, in extreme cases, may clog the MS inlet. TLC plates with aluminum support seem to be more prone to such process than are those with glass support. 

Macromolecules 1989, 22, 3858-3866. (b) Collette, J. W. Tullock, C. W. MacDonald, R. N. Harrell, R. Aaron, C. L. Buck, W. A. Mtilhaupt, R. Burton, C. A. Elastomeric polypropylenes from aluminum-supported tetraaUcyl group IVB catalysts. 2. Chain microstructures, crystallinity, and morphology. Macromolecules 1989, 22, 3858-3866. 

Precoated plates for TLC have been commercially available since 1961. The sorbents may be coated on glass, plastic, or aluminum supports. Sorbents with and without binder, and with and without UV indicators, are available in a variety of layer thicknesses, ranging from 100 pm in the case of plastic plates and high-performance layers to 2311 pm for preparative layers. The largest selection is presented by glass plates, coated to a thickness of 250 pm in the case of analytical layers. ... 

These high-voltage transmission lines are made of aluminum supported with steel cables. 

Takagi, K. Lithographic plates with high sensitivity, printability, and clean ability, method for laser platemaking thereof, aluminum supports thereof, and manufacture thereof. Jpn. Kokai Tokkyo Koho JP 2005070267, 2005 Chem. Abstr. 2005, 142, 325965. 

Figure 33.10 Schematic of an apparatus for the evaporative casting of polymeric membranes from a casting solution consisting of cellulose acetate, acetone, and water the simultaneous downward movement of the phase separation fiont and hquid-gas interface was monitored with a 10-MHz UTDR transducer placed on the underside of the aluminum support surface.

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