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Hardware and software systems for the determination of charged particle parameters in low pressure plasmas using impedance-tuned langmuir probes
Engineering Information Abstracts (Part II) Source: Australasian Physical & Engineering Sciences in Medicine v 20 n 4 Dec 1997. p 214-219 CODEN: AUPMDI ISSN: 0158-9938 Publication Year: 1997 Abstract: A new fibre optic plethysmograph has been designed to monitor respiration non invasively. The device incorporates the idea of using thoracic and abdominal belts similar to conventional inductance plethysmography but uses an optical fibre woven into the belts rather than the usual coiled wire. The fibre optic belts incorporate a loop design in the fibre and rely on ‘macrobending’ losses from laser light transmitted down the fibre when the bend radius of the loop changes during respiration. Changes in lung volume are monitored by analyzing the relatively large resultant changes in light transmitted through the fibre. The output from the light detector has been interfaced to a computer containing a data acquisition card and the resultant intensity trace is monitored in real time using a virtual instrument created using LabVIEW graphical programming. Preliminary results suggest a highly sensitive system capable of detecting small changes in lung volume using a technique which is not susceptible to electrical noise and which is electrically safe. ŽAuthor abstract . 8 Refs. In English EI Order Number: EIP98044165921 Keywords: Biosensors; Fiber optic sensors; Patient monitoring; Plethysmography; Noninvasive medical procedures; Computer aided diagnosis; Light transmission; Real time systems; Computer programming; Computer software Title: HARDWARE AND SOFTWARE SYSTEMS FOR THE DETERMINATION OF CHARGED PARTICLE PARAMETER S IN LO W PR ESSUR E PLASM AS USIN G IMPEDANCE-TUNED LANGMUIR PROBES Author(s): Ye, Yuancai; Marcus, R. Kenneth Corporate Source: Clemson Univ, Clemson, SC, USA Source: Spectrochimica Acta, Part B: Atomic Spectroscopy v 52 n 14 Dec 19 1997. p 2025-2041 CODEN: SAASBH ISSN: 0584-8547 Publication Year: 1997 Abstract: A computer-controlled, impedance-tuned Langmuir probe data acquisition system and processing software package have been designed for the diagnostic study of low pressure plasmas. The combination of impedance-tuning and a wide range of applied potentials Ž plus or minus 100 V. provides a versatile system, applicable to a variety of analytical plasmas without significant modification. The automated probe system can be used to produce complete and undistorted current-voltage Ži-V. curves with extremely low noise over the wide potential range. Based on these hardware and software systems, it is possible to determine all of the important charged particle parameters in a plasma; electron number density Žnrre., ion number density Žnrri., electron temperature ŽTrre., electron energy distribution function ŽEEDF., and average electron energy Ž left angle bracket epsilon right angle bracket .. The complete data acquisition system and evaluation software are described in detail. A Lab View ŽNational Instruments Corporation, Austin, TX. application program has been developed for the Apple Macintosh line of microcomputers to control all of the operational aspects of the
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Langmuir probe experiments. The description here is mainly focused on the design aspects of the acquisition system with the targets of extremely low noise and reduction of the influence of measurement noise in the calculation procedures. This is particularly important in the case of electron energy distribution functions where multiple derivatives are calculated from the obtained i-V curves. A separate C-language data processing program has been developed and is included here to allow the reader to evaluate data obtained with the described hardware, or any i-V data imported in tab separated variable format. Both of the software systems are included on a Macintosh formatted disk for their use in other laboratories desiring these capabilities. ŽAuthor abstract . 29 Refs. In English EI Order Number: EIP98034112192 Keywords: Plasmas; Charged particles; Glow discharges; Computer control; Computer software; Computer hardware; Data acquisition; Current voltage characteristics; Probes; Electrons Title: EXAMINATION OF TRIBOLOGICAL PROPERTIES OF PLASMA SURFACE LAYER USING SPECIAL TEST EQUIPMENT Author(s): Skoric, B.; Kakas, D. Corporate Source: Univ of Novi Sad, Novi Sad, Yugosl Source: TriboTest v 4 n 2 Dec 1997. p 209-218 CODEN: TRITFO ISSN: 1354-4063 Publication Year: 1997 Abstract: The hardness, adhesion, and tribological behaviour of magnetron-deposited coatings ŽTiN and ŽTi, Al.N. have been determined and related to microstructure composition. To enhance the adhesion of the coating, plasma nitriding of substrates was employed. Wear behaviour, coefficient of friction and contact temperature were measured using computerized data acquisition and processing. The bonding force between the coated samples and counter material was monitored and controlled by newly designed and constructed equipment, to keep a constant level of load during sliding. With the new hardware and software, it was possible to monitor on-line the development of the wear process. The hardware consisted of PC computer, piezoelectric transducer, sensors with high sensitivity, microprocessor-controlled measuring system, ADrDA transformer, and multichannel plotter. The wear zone morphology and characteristics of the surface layer structure and other important properties were investigated using scanning electron microscopy ŽSEM. and X-ray diffraction analysis ŽXRD.. Energy dispersive X-ray analysis ŽEDAX. of the wear scars on pins provided essential information on the wear characteristics. Based on the results, the correlations between the mechanical properties, the surface structure, and tribological characteristics are explained. ŽAuthor abstract . 7 Refs. In English EI Order Number: EIP98034104204 Keywords: Ceramic coatings; Titanium nitride; Tribology; Surface structure; Plasma applications; Nitriding; Hardness; Adhesion; Composition Title: ON SOME PC-BASED ELECTRICAL MEASUREMENTS IN EET LABORATORY Author(s): Gapinski, Andrzej J.
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Langmuir probe experiments. The description here is mainly focused on the design aspects of the acquisition system with the targets of extremely low noise and reduction of the influence of measurement noise in the calculation procedures. This is particularly important in the case of electron energy distribution functions where multiple derivatives are calculated from the obtained i-V curves. A separate C-language data processing program has been developed and is included here to allow the reader to evaluate data obtained with the described hardware, or any i-V data imported in tab separated variable format. Both of the software systems are included on a Macintosh formatted disk for their use in other laboratories desiring these capabilities. ŽAuthor abstract . 29 Refs. In English EI Order Number: EIP98034112192 Keywords: Plasmas; Charged particles; Glow discharges; Computer control; Computer software; Computer hardware; Data acquisition; Current voltage characteristics; Probes; Electrons Title: EXAMINATION OF TRIBOLOGICAL PROPERTIES OF PLASMA SURFACE LAYER USING SPECIAL TEST EQUIPMENT Author(s): Skoric, B.; Kakas, D. Corporate Source: Univ of Novi Sad, Novi Sad, Yugosl Source: TriboTest v 4 n 2 Dec 1997. p 209-218 CODEN: TRITFO ISSN: 1354-4063 Publication Year: 1997 Abstract: The hardness, adhesion, and tribological behaviour of magnetron-deposited coatings ŽTiN and ŽTi, Al.N. have been determined and related to microstructure composition. To enhance the adhesion of the coating, plasma nitriding of substrates was employed. Wear behaviour, coefficient of friction and contact temperature were measured using computerized data acquisition and processing. The bonding force between the coated samples and counter material was monitored and controlled by newly designed and constructed equipment, to keep a constant level of load during sliding. With the new hardware and software, it was possible to monitor on-line the development of the wear process. The hardware consisted of PC computer, piezoelectric transducer, sensors with high sensitivity, microprocessor-controlled measuring system, ADrDA transformer, and multichannel plotter. The wear zone morphology and characteristics of the surface layer structure and other important properties were investigated using scanning electron microscopy ŽSEM. and X-ray diffraction analysis ŽXRD.. Energy dispersive X-ray analysis ŽEDAX. of the wear scars on pins provided essential information on the wear characteristics. Based on the results, the correlations between the mechanical properties, the surface structure, and tribological characteristics are explained. ŽAuthor abstract . 7 Refs. In English EI Order Number: EIP98034104204 Keywords: Ceramic coatings; Titanium nitride; Tribology; Surface structure; Plasma applications; Nitriding; Hardness; Adhesion; Composition Title: ON SOME PC-BASED ELECTRICAL MEASUREMENTS IN EET LABORATORY Author(s): Gapinski, Andrzej J.