effect of pulsed infrared lasers on neural conduction and axoplasmic transport in sensory nerves

evaluates the effects of pulsed nd'yag laser light on neural impulse conduction and axoplasmic transport in sensory nerves in rats and cats. the data indicate that q-switched nd'yag laser irradiation can induce a preferential impairment of (1) the synaptic effects of small afferent fibers on dorsal horn cells in the spinal cord and of (2)..

inverse volume-conductor method for noninvasive assessment of nerve injuries

a standard method for characterizing focal nerve lesions is to estimate the fraction of nerve fibers that cross the lesion. in animals, this fraction can be computed electrophysiologically by excising and crushing the nerve to record monophasic compound action potentials (mcaps) whose areas are proportional to the number of active fibers...

the construction of the rfx vacuum vessel

the technologies adopted for constructing the reversed-field pinch experiment (rfx) vacuum vessel are described. the vessel is of all-welded inconel 625 construction, with very tight dimensional tolerances' 1 mm on the 4-m major diameter, and 0.5 mm on the 1-m minor diameter. welding the thin inconel sheets to create the sandwich structur..

a system for systematically preparing atom-probe field-ion-microscope specimens for the study of internal interfaces

a versatile system has been designed and fabricated to prepare atom-probe field-ion-microscope (apfim) specimens in a systematic manner, such that internal interfaces can be positioned in the tips of these wire specimens for subsequent analysis of their chemical composition. this system incorporates both beaker electrolytic and zone elect..

surface hydrophilization during direct silicon bonding

ammonia hydrophilization prior to direct silicon-wafer bonding substantially reduces the deep-center density in the fabricated structures, increases the breakdown voltage of the junctions, and is more promising for the fabricated of high-power devices by the dsb method than is hydrophilization with h/sub 2/so/sub 4/

excimer-laser ablation and etching

the characteristics of excimer lasers and the nature of ablation and etching processes are described. the two kinds of laser ablation mechanisms, thermal and electronic, are discussed. thermal processes all rely on an intense laser pulse to heat a surface very rapidly. electronic mechanisms do not rely on heating. two of these quantum-typ..

mass production back-grinding/wafer-thinning technology for gaas devices

the first mass-production back-grinding technology applicable to a fully-automatic wafer-thinning process in gaas device manufacturing is described. excellent productivity has been realized because the brittleness of gaas has been overcome. a mirror-like stress-free surface was obtained by utilizing the wafer-rotating downfeed grinding me..

planar flexible fiber-optic acoustic sensors

the acoustic sensitivity of optical fibers is considered analytically. high sensitivity is obtained with low bulk modulus, very thick polymeric coatings. the fiber coatings play an important role in determining the fiber acoustic sensitivity. the very thick coating limit is realized by embedding optical fibers in an appropriate elastomer ..

acoustic emission in single filament carbon/polycarbonate and kevlar/polycarbonate composites under tensile deformation

an analysis of envelope signals of acoustic emission (ae) produced from carbon/polycarbonate and kevlar/polycarbonate composites undergoing tensile deformation has been carried out to identify the sources of emission. the kaiser effect (1953) was reproduced to validate the ae technique. two different fiber failure mechanisms, i.e., fiber ..

ultrahigh au/p-gaas schottky barriers due to plasma hydrogenation

gaas surface modification caused by rf plasma hydrogenation has been studied by electrical characterization of subsequently fabricated au/gaas schottky barriers. while the schottky barrier height on n-gaas is found to reduce slightly, exceptionally high barriers have been seen for p-gaas. the effective barrier height of au/p-gaas diodes i..