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|Other titles||Twenty-eight thousand hour xenon hollow cathode life test results.|
|Statement||Timothy R. Sarver-Verhey.|
|Series||[NASA contractor report] -- NASA CR--97-206231., NASA contractor report -- NASA CR-206231.|
|Contributions||Lewis Research Center.|
|The Physical Object|
Download 28,000 hour xenon hollow cathode life test results
28, hour Xenon Hollow Cathode Life Test Results Timothy R. Sarver-Verhey NYMA, Inc. NASA Lewis Research Center Group Brook Park, OH The International Space Station Plasma Contactor System requires a hollow cathode assembly (HCA) with a lifetime of at le hours.
Critical components of the HCA include the hollow cathode and electronCited by: Get this from a library. 28, hour xenon hollow cathode life test results: contract NAS [Timothy R Sarver-Verhey; Lewis Research Center.]. Destructive Evaluation of a Xenon Hollow Cathode After a 28, Hour Life Test Timothy R.
Sarver-Verhey Dynacs Engineering Company, Inc. Prepared for the 34th Joint Propulsion Conference 28,000 hour xenon hollow cathode life test results book Exhibit cosponsored by AIAA, ASME, SAE, and ASEE Cleveland, Ohio, JulyPrepared under Contract NAS National Aeronautics and Space.
Get this from a library. Destructive evaluation of a xenon hollow cathode after a 28, hour life test. [Timothy R Sarver-Verhey; Lewis Research Center.]. 28,000 hour xenon hollow cathode life test results book of hollow cathode operation and life limiting mechanisms An Overview of the Results from an Hour Wear Test of the NSTAR Ion Thruster Destructive Evaluation of a.
Progress towards high-current, long-lifetime hollow cathodes has been made by Goebel and Chu 5,6 in testing a lanathanum hexaboride (LaB 6) bulk-emitting hollow cathode at up to A of. measured on axis in the NEXIS hollow cathode at 25 A of discharge current.
The structure of the hollow cathode serves three main functions. First, some fraction of the thruster propellant is injected through the hollow cathode, and the discharge inside the resulting high neutral pressure region generates a cold, high-density plasma.
experimental results and then coupled with the deposition/desorption model already developed by the authors. The evolution of the surface of the cathode tested hours by Sarver-Verhey has been Hollow Cathode Life Time Model. Q-SUN xenon arc test chambers use air-cooled xenon arc lamps to significantly reduce operating and maintenance expenses.
Lamp life is guaranteed at hours. Q-SUN models Xe-1 and Xe-2 use one lamp and model Xe-3 uses three. Changing lamps is quick and easy and does not interfere with the specimen Size: 2MB.
A hollow cathode lamp containing an inert gas like argon or neon at a very low pressure is used as a light source. Inside the lamp is a metal cathode that contains the same metal as the analyte of analysis. For example, for copper analysis a hollow copper cathode lamp is needed.
For analysis of lead, a hollow lead cathode lamp is required. xenon hollow cathode. In the following, the hollow cathode and experimental investigation are described. Then, a detailed description of the numerical model is provided.
Numerical results from the model are presented at three different operating points of the hollow cathode, and comparisons are made with the mea-sured data. Hollow Cathode Plasma Sources – addressing a paradigm shift in semiconductor industry.
For more than 30 years, nothing much changed regarding plasma sources. Historically, for deposition purposes, plasma sources were most heavily used for PECVD (plasma enhanced CVD) and PVD (physical vapour deposition) applications.
test article as well as the throttling profile used over the course of the test. Section III describes the post-test inspection objectives, as well as the overall approach that was taken. Section IV includes major results of the post-test inspection for the cathode inserts.
Section V then summarizes key findings. of high-current LaB6 hollow cathodes for high-power ion and Hall thruster applications was reported in In this paper, we present results from a larger LaB 6 hollow cathode that reliably produced discharge currents from 10 to 50 A.
In this paper the latest advances in the hollow cathode lifetime modeling carried out at the University of Southampton will be presented. A barium oxide insert depletion model and a surface low work function compounds deposition/depletion model have been already developed by the authors.
Here a procedure to update the plasma parameters relatively to changes of the Author: Michele Coletti, Stephen B. Gabriel. III. HOLLOW CATHODE ION SOURCE While in the past on the Test EBIS we have used several type sources for 1+ injection (ex.
liquid metal ion source, metal vapor vacuum arc source, cesium emitter), on the EBIS used for accelerator operation we have so far used only hollow cathode ion sources. This type sourceAuthor: J Alessi, E.
Beebe, C. Carlson, D. McCafferty, A. Pikin, J. Ritter. Chapter 7 presents the modelling of hollow cathodes and discharges in hol-low geometry.
Three models and results from these are presented. Chapter 8 presents the H-HEAD plasma source and its characterisation. Results from experiments with this source is also given.
Chapter 9 gives a short summary of each paper included in this thesis, em. The hollow cathode effect allows electrical conduction at a lower voltage or with more current in a cold-cathode gas-discharge lamp when the cathode is a conductive tube open at one end than a similar lamp with a flat cathode.
The hollow cathode effect was recognized by Friedrich Paschen in In a hollow cathode, the electron emitting surface is in the inside of the tube. 1) The emission spectrum of a hollow cathode lamp for molybdenum was found to have a sharp peak at nm as long as the lamp current was less than 50 mA.
At higher currents, however, the peak developed a cup-like crater at its maximum. Xenon Arc Testing. Micom offers Xenon arc testing to simulate outdoor and indoor sun exposure on surface finishes, coatings and polymers. Equipments used to conduct such a test are called weatherometers.
ASTM G is a practice used to do xenon arc testing. Glow Discharge Hollow Cathode Hollow Cathode Lamp Neutral Beam Injector Hollow Cathode Discharge These keywords were added by machine and not by the authors.
This process is experimental and the keywords may be updated as the learning algorithm by: Hollow Cathode Lamp - Cadmium - " - Non-Coded: : Industrial & Scientific.
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A flashtube, also called a flash lamp, is an electric arc lamp designed to produce extremely intense, incoherent, full-spectrum white light for very short durations.
Flashtubes are made of a length of thin glass tubing with electrodes at either end and are filled with a gas that, when triggered, ionizes and conducts a high voltage pulse to.
One of the strengths of atomic absorption and other ionizing elemental analysis techniques using optical detection (ICP-OES is the main other one I know of) is that the optical absorption and emission properties at particular wavelengths are highly e this, the reasons for desiring monochromatic, element-specific AAS light sources are as follows.
Purpose: Wewon xenon arc test chamber use xenon arc lamp as a light source, It is a equipment for simulation and strengthening of weathering accelerated aging test, After testing, You can quickly get closely atmospheric aging test results, Used to evaluate the weather resistance of the testing material/ samples.
Hollow Cathode Plasma Electron Emitter (HCPEE) Products. EPL Manufactures four ground-based hollow cathode models, with steady state plasma electron emission current ratings up to A. Operating gasses include Xe, Kr, Ar, Ne, He, N 2 and H 2. All share common design and manufacturing heritage and offer mounting interface options.
hollow cathode will be produced and tested. The result of the analysis will be used to decide on thermouple points during the test. Test results and analysis will be compared.
Also analysis can be enhanced like using joule heating model. This paper discusses a detailed thermal analysis for this LaB 6 hollow Size: KB. One of the topics on the hollow cathode studies is a life test of a discharge cathode.
The keeper disk, orifice plate, and cathode tube of this discharge cathode are made of "high density graphite," which possesses much higher tolerance to ion impingement compared with conventional metal materials. The life test had started in March and Cited by: 2.
Physics Final. STUDY. Flashcards. Learn. Write. Spell. Test. PLAY. Match. Gravity. Created by. Upsideeedwn. Terms in this set (69) a late traveler rushes to catch a plane pulling a suitcase with force directed 30 deg.
above horizontal, if horrizontal force ='s n what is the force on handle. The current in an electron beam in a cathode.
Label the components of the hollow-cathode lamp below Then match the component with its description Each component will be used once when labeling the diagram and once when matching to the description It is made of tungsten It is ionized when a potential of V a applied between the electrodes.
3 Motivation Two major failure modes for conventional hollow cathode – emitter poisoning and heater failure LaB 6 is two orders of magnitude less sensitive to oxygen poisoning1 Erosion rate for LaB 6 is lower for emission currents below 13 A/cm2 (Ref.
2) LaB 6 operation temperature is higher to attain similar emission current densities1 due to higher low-temperature work function. dry the test samples, or the proxim-ity of a body of water to promote dew for-mation.
Random year-to-year variations in the weather, which can cause degradation to vary as much as in successive years at the same location. Seasonal variations (i.e., winter exposure may be only 1/7th as severe as summer exposure).File Size: KB.
Wewon Environmental Chambers Co., Ltd. as a manufacturer and supply xenon test chamber for abroad partners many years.
The mainly product from Wewon Environmental Chambers Co., Ltd.: Xenon Test Chamber, Temperature Humidity Chambers, Walk-in Chambers, Xenon Testing Chamber, Weather Ometer, Weatherometer. A model for the insert chemistry developed by the authors and based on the knowledge of the BaO – CaO – Al2O3 ternary system the ELT discharge cathode insert from the Deep Space 1 life test has been simulated.
The computed data show a good agreement with the experimental one; the agreement increase with the imposition of boundary conditions closer to Cited by: 2.
The cathode schematic adopted in this study is shown in Fig. 1, along with the electrical layout of the main tube, made of a refractory metal (e.g.
tantalum, tungsten, molybdenum), internally houses an electron emitter made of LaB tube ends with an orifice plate, which is in contact with the insert and is considered to be made of the same material of Cited by: Hollow Cathode Lamps filled with Deuterium gas are sometimes used as background correction devices in atomic absorption analysis.
” lamps can be used in all instruments with the exception of Varian, for which we offer a shortened Size: KB.
With walk in option you have a facility to test your product in bulk quantity and even for the products which are larger in size. This chamber also known as Uv Test Chamber and Xenon Lamp Weather Resistance Test Chamber.
Weiber xenon test chambers are easy to install, easy to program and easy to operate. Analytical West Offers Genuine Photron Deuterium Arc Lamps and Hollow Cathode in Both Data Coded and Non-Coded Types. DISCLAIMER: Analytical West is not affiliated in any way with Agilent Technologies.
Any claims of compatibility are the sole claim of Analytical West and our manufacturers, and have not been reviewed, approved, or endorsed by Agilent Technologies. of the hollow cathode are provided. The results of this study are going to be used in deciding the design of the hollow cathode heater to be manufactured.
THE THEORETICAL PREDICTION The basic operation mechanism of a hollow cathode is as follows: The insert (LaB6) is heated by an external heater coil. However, the results from XENON can be seen as the preparation for the next step, XENON1T.
As XENON1T has about 2kg of Xe in its two-ton active xenon target (a factor of 70 more compared to the 29g used in XENON) it will be more sensitive to this rare decay.
Moreover, the background in XENON1T is a factor of 30 smaller in the region. SHIPPING IS ON US! Free on orders of $ or more ; Select the Free Shipping FedEx Ground option at checkout * Free shipping is valid on orders of $ or more via FedEx Ground to all locations in the Continental 48 States, after promotions and discounts are applied.The commercially available xenon arrives with a Kr-nat in xenon concentration on the order of (ppm, parts per million) to (ppb, parts per billion) and needs to be purified down to a concentration of x (ppt, parts per trillion).
To put this in relation: When purchased, an Olympic swimming pool filled with liquid xenon.Xenon Arc Lamp Aging Test Chamber Product introduction: Xenon Aging Test Chamber can simulate the damage caused by sunlight, rain and dew, using xenon lamp simulation of the effect of sunlight, the use of condensed moisture to simulate the rain and dew, the test material is placed in a certain temperature alternating light and moisture cycling program for aging testing.