Metallic foil

The use of thin metal foils (Be, Cu, Ti) reduces the radiation attenuation in the window or serves as pre-filtration for various measurement set-ups. 

Comparison of the specific surface estimated by the adsorption of different vapours on some powders and metal foils ... 

Figure 5 shows a typical metallic foil strain gauge. It consists of an etched grid of very thin foil attached to a thin insulating backing material. The... 

Fig. 4. Diffusion bonding process (a) apply metal foil and cut to shape, (b) lay up desired pHes, (c) vacuum encapsulate and heat to fabrication temperature, (d) apply pressure and hold for consoHdation cycle, and (e) cool, remove, and clean part.

Fiber dmms can be produced to meet a wide variety of requirements. They can be constmcted with adhesives for water resistance, their interiors can be coated, their walls and ends can incorporate metal foil or asphalt-impregnated pHes, and their exteriors can be decorated by painting, varnishing, and silk screening for both ornamental and functional purposes. 

Film and foil adhesives based on internally plastici2ed copolymer adhesives have been suggested. For instance, vinyl acetate—ethylene or vinyl acetate—acrylate copolymers may be used for adhesion of films to porous surfaces. For metallic foil adhesion, copolymers containing carboxylate functionahty are suggested. 

Adhesives. Poly(vinyl alcohol) is used as a component in a wide variety of general-purpose adhesives to bond ceUulosic materials, such as paper and paperboard, wood textiles, some metal foils, and porous ceramic surfaces, to each other. It is also an effective binder for pigments and other finely divided powders. Both fully and partially hydrolyzed grades are used. Sensitivity to water increases with decreasing degree of hydrolysis and the addition of plasticizer. Poly(vinyl alcohol) in many appHcations is employed as an additive to other polymer systems to improve the cohesive strength, film flexibiUty, moisture resistance, and other properties. It is incorporated into a wide variety of adhesives through its use as a protective coUoid in emulsion p olymerization. 

The primary substrates or support iaclude many types of paper and paperboard, polymer films such as polyethylene terephthalate, metal foils, woven and nonwoven fabrics, fibers, and metal cods. Although the coating process is better suited to continuous webs than to short iadividual sheets, it does work very well for intermittent coating, such as ia the printing process. In general, there is an ideal coater arrangement for any given product. 

The finish may be a coating (paint, asphaltic, resinous, or polymeric), a membrane (coated fmt or paper, metal foil, or laminate of plastic, paper, foil or coatings), or sheet material (fabric, metal, or plastic). 

In LT motors, a standard test finger as shown in Figure 11.7 is used, connected by an incandescent lamp to one pole of a supply of at least 40 V, the other pole of the supply being connected to the parts intended to be live in normal service. All parts must be connected electrically. The lamp should not glow when an attempt is made to touch the bare live parts or insufficiently insulated parts. Insufficiently insulated parts may be covered with a metal foil connected to tho.se parts that are live in normal service. Conducting parts covered with varnish or enamel only or protected by oxidation or by a similar process may be considered as insufficiently insulated. In HT motors, the clearance is verified with the minimum clearance required to withstand the dielectric test as in Section 11.4.8,... 

The most common form of energy deposition used for planar shock wave research has been electrical resistance heating of a metal foil which vaporizes, driving a flyer plate to a high velocity before it impacts a specimen. In a hybrid system incorporation both resistance vaporization and an electromagnetic push, velocities to 18 km/s are reported for kapton flyer plates which are... 

Figure 2 Molybdenum K-edge X-ray absorption spectrum, ln(i /i ) versus X-ray energy (eV), for molybdenum metal foil (25- jjn thick), obtained by transmission at 77 K with synchrotron radiation. The energy-dependent constructive and destructive interference of outgoing and backscattered photoelectrons at molybdenum produces the EXAFS peaks and valleys, respectively. The preedge and edge structures marked here are known together as X-ray absorption near edge structure, XANES and EXAFS are provided in a new compilation of literature entitled X-rsy Absorption Fine Structure (S.S. Hasain, ed.) Ellis Norwood, New York, 1991.

Figures Background-subtracted, normalized, and ili -weighted Mo K-edge EXAFS, versus k (A ), for molybdenum metal foil obtained from the primary experimental data of Figure 2 with Eq = 20,025 eV.

The Fourier transform of the EXAFS of Figure 5 is shown in Figure 6 as the solid curve It has two large peaks at 2.38 and 2.78 A as well as two small ones at 4.04 and 4.77 A. In this example, each peak is due to Mo—Mo backscattering. The peak positions are in excellent correspondence with the crystallographically determined radial distribution for molybdenum metal foil (bcc)— with Mo—Mo interatomic distances of2.725, 3.147, 4.450, and 5.218 A, respectively. The Fourier transform peaks are phase shifted by -0.39 A from the true distances. 

Papier-fabrik, /. paper factory, paper mill, -fabrikant, m. paper maker, -fabrikation, /. paper making, -farbe, /. paper color, -filter, n. paper filter, -flftche, /. paper sur-faee, surfaee of the paper, -gam, n. paper yarn, paper twine, -handel, m. paper trade stationery, -handlung, /. stationer s shop, -holz, n. pulpwood. -jod, n. a solution of iodine and potassium iodide for test paper, papierkaschiert, a. paper-covered, paper-baeked (as metal foil). 

Hertz s last piece of experimental work was done when his health was deteriorating and he was devoting most of his research time to intensive theoretical work on the logical foundations of mechanics. In 1892 in his laboratoi-y in Bonn, he discovered that cathode rays could pass through thin metallic foils. He published a short paper on the subject, but did not pursue the matter further. Instead he handed his apparatus and his ideas over to Philipp Lenard (1862—1947), his assistant in Bonn. Lenard pushed Hertz s suggested research so far that Lenard received the Nobel Prize in Physics in 1905 for his work on cathode rays. ... 

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