ultrasonic investigation of the structure of heat-treated bentonite glass fibers

ultrasonic techniques were used to monitor the structural changes that occur in leachable bentonite glass fibers as a result of specially selected thermal treatments. values of the parameters time, velocity of propagation of ultrasonic waves, and the young's modulus were determined for fibers that had been subjected to various temperature..

surface microfabrication of a gold surface in argon using scanning tunneling microscopy

using a scanning tunneling microscope which can operate in a high- purity argon atmosphere, the generation of rectangular pits in a polycrystalline gold sample is demonstrated. unlike the common method of applying voltage pulses to the tip, these are fabricated by scanning a small portion of the surface at a higher tip bias. the structure..

chemistry of carbon fibre surfaces and its effect on interfacial phenomena in fibre/epoxy composites

the properties of the fibre/resin interface in carbon fibre/epoxy composites can play a dominant role in governing the overall performance of the material. understanding the interactions occurring at the interface and being able to tailor them to give a desired composite property is of great importance. a variety of commercial treatments ..

starburst polymers

universtiy researchers are developing a new family of polymers that will make possible the design and introduction of novel products with unique properties ion the 1990s - new reinforcements for composites, novel coatings, adhesives, lubricants, nonlinear fiber-optic devices, conductive plastics and drug delivery systems these new materia..

improvement of regrown interface in inp organo-metallic vapor phase epitaxy

it is shown that a preheating process in a pure hydrogen atmosphere with a (nh//4)//2s//x treatment was effective for improvement of the regrown interface in inp organometallic vapor phase epitaxy (omvpe). the carrier concentration was under 5 $multiplied by$ 10**1**5 cm** $minus$ **3 in the entire region after the regrowth, even if we ca..

colorimetric activity assays of enzyme-modified mir fibers

the object of this investigation is the determination of the activity of enzymes, for instance, glucose oxidase (gox), immobilized on chalcogenide and silver halide fiber surfaces. after different ways of chemical modification of the fiber surfaces, two different silanes, 3-aminopropyltriethoxysilane (3-apts) and $gamma$ -glycidoxypropylt..

fiber-optic remote detection of pesticides and related inhibitors of the enzyme acetylcholine esterase

we present a novel method for the remote detection of inhibitors (e.g., pesticides) of the enzyme acetylcholine esterase (ache) with a fiber-optic photometer based exclusively on the use of solid-state opto-electronic components including light-emitting diodes and photodiodes. the method employs a yellow synthetic enzyme substrate which i..

compression failure in reduced adhesion fiber laminates

the compressive strength of fiber composites is of key interest in many strength critical composite structures, due to the generally lower failure values relative to tension dominated stress states. the general understanding of the factors that control compression failure is quite rudimentary, and as a consequence strength controlled desi..

zno-modified high modulus glass fibers

it was found that zinc oxide is a modifier that effectively increases the modulus of aluminate and silicate glass fibers. glass fibers having a higher fiber modulus than that of s-glass were prepared by modifying aluminate and silicate composition with 5-25 mol zno under conventional glass-forming conditions by melting the mixed oxide pow..

upgrading of low-grade jute and cuttings part iii: large-scale application and the processing of jute fibres by means of enzymes

a major problem for the jute industry is how to utilize effectively the large proportion of low-grade jute and cuttings in the total amount of raw jute delivered to the mills. by using an enzymatic method of softening and cleaning of low-grade jute and cuttings developed at the bangladesh jute research institute with financial assistance ..