a low energy van de graaff accelerator for the study of semiconductor detector surfaces and of the stopping power of biological materials

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superconducting structures for a 130 mev recyclotron

reports feasibility studies of a proposed 3 ghz recyclotron using 20 cell rf structures of spherical shape. as first step a 5 cell nb cavity was fabricated by deep drawing and electron beam welding. only chemical etching was used as global surface treatment after detection of the breakdown location by a resistor network a local mechanical..

improved liquid phase epitaxial gaas for low series resistance schottky barrier mixer diodes

millimeter wave schottky barrier mixer diodes are extremely important devices for radio astronomy. the performance of the schottky diodes depends largely on the characteristics and quality of the gaas epitaxial material used. systematic manipulation of the liquid phase epitaxial growth conditions and substrate surface treatments has yield..

cross-linked fibrinogen dimers demonstrate a feature of the molecular packing in fibrin fibers

a stable population of fibrinogen dimers cross-linked by factor xiiia has been prepared and examined in the electron microscope. the trinodular fibrinogen molecules are cross-linked through their outer nodules in an end-to-end, non-overlapping fashion. these dimers form normal banded fibers after treatment with the clotting enzyme, thromb

cleaning systems for pcb fabrication

printed circuit technology demands a high level of dependability and performance from electronic equipment. field failures do occur, however, often caused by soldering flux residues and other surface contamination remaining on the circuit boards after manufacture. the removal of soldering flux residues and other contaminants has become ne..

design criteria for ion implantation equipment for surface treatment

ion implantation has become widely used as a means of fabricating semiconductor devices, and sophisticated equipment has been developed for this purpose. some very different problems arise in the more novel application of ion implantation to the provision of resistance to wear or corrosion. examples of the industrial success of the proces..

low light level imaging tube with gaas photocathode

describes the structure and fabrication of gaas photocathodes an ultra-high vacuum transfer equipment and the processes of growth, cleaning and activation of the semiconductor surface are briefly described

development of high-performance metal fiber brushes

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low capacitance josephson junctions

superconducting tunnel junctions of reduced junction capacitance can be prepared by backscattering aluminum oxide onto the base electrode surface concurrently with cleaning it prior to tunnel barrier formation. a process of fabricating good quality/low capacitance junctions using nb base electrodes is described as an example. the samples ..

a fourier-transform infrared spectroscopic study of the hydrolytic stability of silane coupling agents on e-glass fibres

fourier-transform (ft) infrared spectroscopy has been applied to study the hydrothermal degradation of various coupling agents on e-glass fibers. the coupling agents studied include gamma-methacryloxypropyltrimethoxysilane, vinyltrimethoxysilane, and cyclohexyltrimethoxysilane. the amount of coupling agent on e-fibers was measured as a fu..