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Sample records for bakelite

  1. Study of Performance of Bakelite Resistive Plate Chamber (RPC)

    CERN Document Server

    Ganai, R; Roy, A; Muduli, B; Chattopadhyay, S; Ahammed, Z; Das, G; Ramnarayan, S

    2016-01-01

    Resistive Plate Chamber (RPC) is a type of gaseous detector having excellent time and position resolutions. VECC is involved in the R\\&D of indigenously developed bakelite RPCs. The largest size of bakelite RPC developed in India is 100 cm $\\times$ 100 cm. We present here the test results of a bakelite sample along with the cosmic ray test results of a bakelite RPC (30 cm $\\times$ 30 cm $\\times$ 0.2cm) fabricated at VECC. The steps taken towards the development of a large size (240 cm $\\times$ 120 cm $\\times$ 0.2 cm) bakelite RPC have also been discussed.

  2. Recycling Waste Bakelite As A Carbon Resource In Ironmaking

    Directory of Open Access Journals (Sweden)

    James Ransford Dankwah

    2015-02-01

    Full Text Available Abstract Bakelite is a 3-dimensional cross-linked network structured thermosetting polymer which is difficult to recycle after use. However it contains high levels of carbon and CaCO3 that can be recovered for use as reductant and fluxing agent in ironmaking. In this work we report the use of post-consumer bakelite as reductant for the production of metallic iron from iron oxide in a horizontal tube furnace through the composite pellet approach.Gas emission studies were conducted by pyrolysing raw bakelite at different temperatures within the temperature range 1200-1600 C in a horizontal tube furnace. Following thiscomposite pellets were then formed from mixtures of iron oxide and post-consumer bakelite.The iron oxide-bakelite composites were heated from room temperature to 1200 C and then between 1200-1600 C in a continuous stream of pure argon and the off gas was analysed continuously using an infrared IR gas analyser. Elemental analyses of samples of the reduced metal were performed chemically for its oxygen content using a LECO oxygennitrogen analyser. The extent of reduction after ten minutes was determined from the oxygen content. Gas emission studies revealed the emission of large volumes of the reductant gases CO and CH4along with CO2.It is further demonstrated that post-consumer bakelite is effective at reducing iron oxide to produce metallic iron.

  3. Study of Glass and Bakelite Properties as Electrodes in RPC

    CERN Document Server

    Manisha,; Shahi, J S

    2016-01-01

    India-based Neutrino Observatory (INO) collaboration is planning to build a magnetized Iron-CALorimeter detector (ICAL) for the study of atmospheric neutrinos. ICAL detector consists of 151 layers of magnetized iron plates interleaved with Resistive Plate Chambers (RPCs) as active detector elements with a total mass of 50 kton. Resistive Plate Chambers are gaseous detectors made up of two parallel electrodes of high bulk resistivity like float glass and bakelite. These detectors are extensively used in several high energy physics experiments since 1980s because of high count rate, excellent time as well as spatial resolutions, simple to fabricate and operate. Due to detector aging issue, it is necessary to characterize electrode material so as to select appropriate electrode material before fabricating the detector. In the present studies, we measured bulk resistivity and surface current of glass as well as bakelite. Bulk resistivity of bakelite is ~ 100 times less than that of glass and surface current of ba...

  4. Influence of Temperature and Humidity on Bakelite Resistivity

    CERN Document Server

    Arnaldi, R; Barret, V; Bastid, N; Blanchard, G; Chiavassa, E; Cortese, P; Crochet, Philippe; Dellacasa, G; De Marco, N; Dupieux, P; Espagnon, B; Fargeix, J; Ferretti, A; Gallio, M; Lamoine, L; Luquin, Lionel; Manso, F; Mereu, P; Métivier, V; Musso, A; Oppedisano, C; Piccotti, A; Rahmani, A; Royer, L; Roig, O; Scalas, E; Scomparin, E; Vercellin, Ermanno

    1999-01-01

    Presentation made at RPC99 and submitted to Elsevier PreprintThe use of phenolic or melaminic bakelite as RPC electrodes is widespread. The electrode resistivity is an important parameter for the RPC performance. As recent studies have pointed out, the bakelite resistivity changes with temperature and is influenced by humidity. In order to gain a quantitative understanding on the influence of temperature and humidity on RPC electrodes, we assembled an apparatus to measure resistivity in well-controlled conditions. A detailed description of the experimental set-up as well as the first resistivity measurements for various laminates in different environmental conditions are presented.

  5. The bakelite for the RPCs of the experiment CMS

    OpenAIRE

    Altieri, S.; Bruno, Giacomo Luca

    2000-01-01

    Results from aging tests on the bakelite used for the CMS RPCs are presented. Samples of melaminic bakelite were exposed to a heavy gamma and neutron radiation. Data on the bulk resistivity were collected while accumulating gamma and neutron doses and particles fluence up to values well beyond those expected in 10 years of RPCs operation in the barrel region of CMS. The test with gamma radiation was performed at the CERN Gamma Irradiation Facility (GIF) with a 20 Ci 137Cs source. A total abso...

  6. Recycling Waste Bakelite As A Carbon Resource In Ironmaking

    OpenAIRE

    James Ransford Dankwah; Emmanuel Baawuah

    2015-01-01

    Abstract Bakelite is a 3-dimensional cross-linked network structured thermosetting polymer which is difficult to recycle after use. However it contains high levels of carbon and CaCO3 that can be recovered for use as reductant and fluxing agent in ironmaking. In this work we report the use of post-consumer bakelite as reductant for the production of metallic iron from iron oxide in a horizontal tube furnace through the composite pellet approach.Gas emission studies were conducted by pyrolysin...

  7. Study of Glass and Bakelite properties as electrodes in RPCs

    OpenAIRE

    Manisha,; Bhatnagar, V.; Shahi, J. S.

    2016-01-01

    India-based Neutrino Observatory (INO) collaboration is planning to build a magnetized Iron-CALorimeter detector (ICAL) for the study of atmospheric neutrinos. ICAL detector will be a stack of 151 layers of magnetized iron plates interleaved with Resistive Plate Chambers (RPCs) as active detector elements with a total mass of 50 kton. Resistive Plate Chambers are gaseous detectors made up of two parallel electrodes of high bulk resistivity like float glass and bakelite. These detectors are ex...

  8. Development of linseed oil-free bakelite resistive plate chambers

    CERN Document Server

    Biswas, S; Bose, S; Chattopadhyay, S; Saha, S; Viyogi, Y P

    2009-01-01

    In this paper we would like to present a few characteristics of the Resistive Plate Chambers (RPC) made of a particular grade of bakelite paper laminates (P-120, NEMA LI-1989 Grade XXX), produced and commercially available in India. This particular grade is used for high voltage insulation in humid conditions. The chambers are tested with cosmic rays in the streamer mode using argon, tetrafluroethane and isobutane in 34:59:7 mixing ratio. In the first set of detectors made with such grade, a thin coating of silicone fluid on the inner surfaces of the bakelite was found to be necessary for operation of the detector. Those silicone coated RPCs were found to give satisfactory performance with stable efficiency of >90% continuously for a long period as reported earlier. Results of the crosstalk measurement of these silicone coated RPC will be presented in this paper. Very recently RPCs made with the same grade of bakelite but having better surface finish, are found to give equivalent performance even without any ...

  9. Bakelite chambers for time-of-flight measurements

    CERN Document Server

    Cwiok, M; Górski, M; Królikowski, J

    1999-01-01

    We report on the search of composite organic materials with the volume resistivity ranging from 10 sup 8 to 10 sup 1 sup 1 OMEGA cm. Materials having resistivity in this range may be used for electrodes of thin gap Parallel Plate Avalanche Chambers. Gas detectors of such structure and operated at increased gas pressure allow, potentially, a sub-nanosecond time resolution. Using bakelite-like material with electrical properties well tuned during manufacturing opens the possibility to overcome limitations related to the semi-conductive glass employed usually for ultrafast gas detectors of parallel plate structure for time-of-flight technique.

  10. The bakelite for the RPCs of the experiment CMS

    CERN Document Server

    Altieri, S; Bruno, G; Guida, R; Merlo, M; Ratti, S P; Riccardi, C; Torre, P; Vitulo, P; Mognaschi, E R; Abbrescia, M; Colaleo, A; Iaselli, Giuseppe; Loddo, F; Maggi, M; Marangelli, B; Natali, S; Nuzzo, S; Pugliese, G; Ranieri, A; Romano, F

    2000-01-01

    Results from aging tests on the bakelite used for the CMS RPCs are presented. Samples of melaminic bakelite were exposed to a heavy gamma and neutron radiation. Data on the bulk resistivity were collected while accumulating gamma and neutron doses and particles fluence up to values well beyond those expected in 10 years of RPCs operation in the barrel region of CMS. The test with gamma radiation was performed at the CERN Gamma Irradiation Facility (GIF) with a 20 Ci /sup 137/Cs source. A total absorbed dose of 5 Gy was accumulated during an irradiation period of about one month. The test with both neutron and gamma radiation was held at the Triga Mark II 250 kW reactor located in Pavia. A total of 80 h of exposure were accumulated integrating a neutron and gamma dose of about 80 Gy and a fast neutron fluence of some 10/sup 11/ cm/sup -2/. Experimental data on dose rate in both the test facilities have been compared to simulation output and show a good agreement. (4 refs).

  11. The bakelite for the RPCs of the experiment CMS

    Science.gov (United States)

    Altieri, S.; Belli, G.; Bruno, G.; Guida, R.; Merlo, M.; Ratti, S. P.; Riccardi, C.; Torre, P.; Vitulo, P.; Mognaschi, E. R.; Abbrescia, M.; Colaleo, A.; Iaselli, G.; Loddo, F.; Maggi, M.; Marangelli, B.; Natali, S.; Nuzzo, S.; Pugliese, G.; Ranieri, A.; Romano, F.

    2000-12-01

    Results from aging tests on the bakelite used for the CMS RPCs are presented. Samples of melaminic bakelite were exposed to a heavy gamma and neutron radiation. Data on the bulk resistivity were collected while accumulating gamma and neutron doses and particles fluence up to values well beyond those expected in 10 years of RPCs operation in the barrel region of CMS. The test with gamma radiation was performed at the CERN Gamma Irradiation Facility (GIF) with a 20 Ci 137Cs source. A total absorbed dose of 5 Gy was accumulated during an irradiation period of about one month. The test with both neutron and gamma radiation was held at the Triga Mark II 250 kW reactor located in Pavia. A total of 80 h of exposure were accumulated integrating a neutron and gamma dose of about 80 Gy and a fast neutron fluence of some 10 11 cm-2. Experimental data on dose rate in both the test facilities have been compared to simulation output and show a good agreement.

  12. Study of the molecular structure and dynamics of bakelite with neutron cross section measurements

    International Nuclear Information System (INIS)

    The molecular structure and dynamics of calcined bakelite were studied with neutron transmission and scattering cross section measurements. The total cross sections determined were correlated with data obtained with infra-red spectroscopy, elemental analysis and other techniques to get the probable molecular formulae of bakelite. The total cross section determined showed a deviation smaller than 5% from the literature values. The frequency distribution as well as overall experimental results allowed to suggest a structural model like polycyclic hydrocarbons for bakelite calcined at 8000 C. (F.E.). 65 refs, 31 figs, 5 tabs

  13. EFFECT OF BAKELITE INTERLAYER POWDER ON FRICTION STIR SPOT WELDING OF THERMOPLASTIC POLYMERS

    OpenAIRE

    Bekir ÇEVİK

    2014-01-01

    In this study, effect of bakelite interlayer powder on friction stir spot welding of polyethylene materials were investigated. 3 mm thick polyethylene materials were used in the experiments. 900 rpm rotational speed, 70, 100 and 130 seconds stirring time and 60 second waiting time were selected for the welding processes. Tensile-shear tests were applied on welded specimens and mechanical performances were determined

  14. Fabrication and Characterisation of Oil-Free Large Bakelite Resistive Plate Chamber

    CERN Document Server

    Ganai, Rajesh; Agarwal, Kshitij; Ahammed, Zubayer; Choudhury, Subikash; Chattopadhyay, Subhasis

    2015-01-01

    A large (240 cm $\\times$ 120 cm $\\times$ 0.2 cm) oil-free bakelite Resistive Plate Chamber (RPC) has been developed at VECC-Kolkata using locally available P-301 OLTC grade bakelite paper laminates. The chamber has been operated in streamer mode using Argon, Freon(R134a) and Iso-butane in a ratio of 34:57:9 by volume. The electrodes and glue samples were characterised by measuring their electrical parameters like bulk resistivity and surface resistivity. The performance of the chamber was studied by measuring the efficiency, time resolution and uniformity in detection of cosmic muons. The chamber showed an efficiency $>$95$\\%$ and time resolution ($\\sigma$) of $\\sim$0.83 ns. Details of the material characterisation, fabrication procedure and performance studies have been discussed.

  15. Study of RPC bakelite electrodes and detector performance for INO-ICAL

    CERN Document Server

    Kumar, Ashok; Hasbuddin, Md; Kumar, Praveen; Kumar, Purnendu; Kaur, Daljeet; Mishra, Swati; Naimuddin, Md

    2014-01-01

    The Resistive Plate Chambers (RPCs) are going to be used as the active detectors in the India-based Neutrino Observatory (INO)-Iron Calorimeter (ICAL) experiment for the detection and study of atmospheric neutrinos. In this paper, an extensive study of structural and electrical properties for different kind of bakelite RPC electrodes is presented. RPCs fabricated from these electrodes are tested for their detector efficiency and noise rate. The study concludes with the variation of efficiency, leakage current and counting rate over the period of operation with different gas compositions and operational conditions like temperature and relative humidity.

  16. Long Term Performance Studies of Large Oil-Free Bakelite Resistive Plate Chamber

    CERN Document Server

    Ganai, Rajesh; Shiroya, Mehul Kumar; Agarwal, Kshitij; Ahammed, Zubayer; Choudhury, Subikash; Chattopadhyay, Subhasis

    2016-01-01

    Several high energy physics and neutrino physics experiments worldwide require large-size RPCs to cover wide acceptances. The muon tracking systems in the Iron calorimeter (ICAL) in the INO experiment, India and the near detector in DUNE at Fermilab are two such examples. A (240 cm $\\times$ 120 cm $\\times$ 0.2 cm) bakelite RPC has been built and tested at Variable Energy Cyclotron Centre, Kolkata, using indigenous materials procured from the local market. No additional lubricant, like oil has been used on the electrode surfaces for smoothening. The chamber is in operation for $>$ 365 days. We have tested the chamber for its long term operation. The leakage current, bulk resistivity, efficiency, noise rate and time resolution of the chamber have been found to be quite stable during the testing peroid. It showed an efficiency $>$ 95$\\%$ with an average time resolution of $\\sim$0.83 ns at the point of measurement at 9000 V throughout the testing period. Details of the long term performance of the chamber have be...

  17. Investigation of mass attenuation coefficients of water, concrete and bakelite at different energies using the FLUKA Monte Carlo code

    International Nuclear Information System (INIS)

    The mass attenuation coefficients of water, bakelite and concrete sample defined in the simulation package were obtained using the FLUKA Monte Carlo code at 59.5, 80.9, 140.5, 356.5, 661.6, 1173.2 and 1332.5 keV photon energies. The results for the mass attenuation coefficients obtained by simulation have been compared with experimental and the theoretical ones and good agreement has been observed. The results indicate that this process can be followed to determine the data on the attenuation of gamma-rays with the several energies in other materials. Also, the deposited energy by 661.6 keV photons at several thicknesses of each media was determined as being an important data for radiation shielding studies. (author)

  18. Exposure buildup factors for bakelite, perspex and magnox-A12 up to 40 m.f.p. using the interpolation method

    Science.gov (United States)

    Brar, G. S.; Sandhu, Apjit Kaur; Singh, Makhan; Mudahar, Gurmel S.

    1994-11-01

    The Geometric Progression (G-P) fitting parameters have been computed with respect to the equivalent atomic number for the composite materials of bakelite and perspex by the interpolation method. These parameters are then used to generate the exposure buildup factors up to 40 m.f.p. in the energy range of 0.015-15.0 MeV for these materials. The behaviour of buildup factors is shown in the form of plots as a function of penetration depth.

  19. Temperature and humidity dependence of bulk resistivity of bakelite for resistive plate chambers in CMS

    CERN Document Server

    Ahn, S H; Bahk, S Y; Gapienko, V A; Hong, B; Hong, S J; Jung, S Y; Kim, J Y; Kim, Y J; Kim, Y U; Koo, D G; Lee, K S; Lee, S J; Lee, Y L; Lim, I T; Nam, S K; Pac, M Y; Park, S K; Ra, Y S; Rhee, J T; Seo, S W; Sim, K S

    2000-01-01

    This paper presents data obtained in a systematic study on the bulk resistivity of Korean bakelike as a function of temperature in the range 20-30 degrees C and relative humidity in the range 35-65%. Strong dependence of resistivity on both temperature and humidity was observed. Measurements were carried out in the framework of R&D work on resistive plate chambers which will be used in the CMS detector. (4 refs).

  20. Application of mixed programming method in bakelite tea during processing%混合编程法在胶木茶盘加工中的应用

    Institute of Scientific and Technical Information of China (English)

    刘刚; 陈志祥

    2013-01-01

    With the progress of science and technology,machinery manufacturing industry is developing rapidly.Gradually from the most basic manual programming to the automatic programming,but any kind of CAM software on the market has its own defect,because all CAM software generated automatically from its core module,the generated program can produce a product,but not necessarily the most reasonable route and the save time.Then according to the different products generated by different CAM software manual programming and program is a combination,optimization,will greatly improve the production efficiency,reduce production cost.%  随着科技的进步,机械制造业发展迅速。从最基本的手工编程逐渐发展到自动编程,但市场上任何一种 CAM 软件都有自身的缺陷,因为所有的 CAM 软件自动生成的程序都来自于它核心模块,它所生成的程序可以加工出产品,但不一定是最合理的路线和最省时间的工艺。那么根据不同的产品通过手工编程加上不同 CAM 软件生成的程序进行一个组合、优化,将会大大的提高生产效率,从而降低生产成本。

  1. TERMOPLASTİK POLİMERLERİN SÜRTÜNME KARIŞTIRMA NOKTA KAYNAĞINA BAKALİT ARA TABAKA TOZUNUN ETKİSİ

    OpenAIRE

    Bekir ÇEVİK

    2014-01-01

    In this study, effect of bakelite interlayer powder on friction stir spot welding of polyethylene materials were investigated. 3 mm thick polyethylene materials were used in the experiments. 900 rpm rotational speed, 70, 100 and 130 seconds stirring time and 60 second waiting time were selected for the welding processes. Tensile-shear tests were applied on welded specimens and mechanical performances were determined.

  2. A modified method for the synthesis of polycondensate phenolic resin with iminodiacetic caid (IDA) functional group for treatment of alkaline waste from reprocessing plants (Preprint no. SST-10)

    International Nuclear Information System (INIS)

    Synthesis of bakelite type resin with iminodiacetic acid(IDA) group was carried out. The product formed by following the procedure published in literature was found to be unstable in alkaline solution and the reaction rate was considerably slow. A modified method for preparing the resin with improved stability is discussed in this paper. (author). 2 refs., 2 tab

  3. TERMOPLASTİK POLİMERLERİN SÜRTÜNME KARIŞTIRMA NOKTA KAYNAĞINA BAKALİT ARA TABAKA TOZUNUN ETKİSİ

    Directory of Open Access Journals (Sweden)

    Bekir ÇEVİK

    2014-05-01

    Full Text Available In this study, effect of bakelite interlayer powder on friction stir spot welding of polyethylene materials were investigated. 3 mm thick polyethylene materials were used in the experiments. 900 rpm rotational speed, 70, 100 and 130 seconds stirring time and 60 second waiting time were selected for the welding processes. Tensile-shear tests were applied on welded specimens and mechanical performances were determined.

  4. Optimisation and Characterisation of Glass RPC for India-based Neutrino Observatory Detectors

    OpenAIRE

    Kanishka, R.; Bhatnagar, Vipin; Indumathi, D.

    2016-01-01

    The proposed magnetised Iron CALorimeter detector (ICAL) to be built in the India-based Neutrino Observatory (INO) laboratory aims to detect atmospheric muon neutrinos. In order to achieve improved physics results, the constituent components of the detector must be fully understood by proper characterisation and optimisation of various parameters. Resistive Plate Chambers (RPCs) are the active detector elements in the ICAL detector and can be made of glass or bakelite. The number of RPCs requ...

  5. A theoretical way to determine gamma-ray mass attenuation coefficients of materials

    OpenAIRE

    ERMİŞ, ELİF EBRU; PİLİÇER, Ercan; ÇELİKTAŞ, CÜNEYT

    2015-01-01

    The gamma-ray mass attenuation coefficients of various absorber materials such as Ag, Al, Au, Bakelite, Cu, Fe, Pb, Plexiglas, Si, Sn, water, and Zn were determined theoretically at different gamma-ray energies and different absorber thicknesses in order to investigate how the number of gamma photons and their energies affect the calculation of mass attenuation coefficients of the absorbers since no study such a comprehensive work here was encountered. For this purpose, the FLUKA ...

  6. Large drift tube arrays with external delay line readout

    International Nuclear Information System (INIS)

    The construction and performance of 2 meter long, 5 cm diameter, circular drift tubes made of 1 mm thick bakelite paper coated inside with conductive paint. The longitudinal coordinate is read-out with an external delay line system. The measured spatial resolution obtained from the drift time is close to 180 μm (one standard deviation). A system of 1100 tubes has been built for a muon experiment

  7. Determination of scatter fractions of some materials by experimental studies and Monte Carlo calculations

    CERN Document Server

    Meric, N; Bor, D

    1999-01-01

    Scatter fractions have been determined experimentally for lucite, polyethylene, polypropylene, aluminium and copper of varying thicknesses using a polyenergetic broad X-ray beam of 67 kVp. Simulation of the experiment has been carried out by the Monte Carlo technique under the same input conditions. Comparison of the measured and predicted data with each other and with the previously reported values has been given. The Monte Carlo calculations have also been carried out for water, bakelite and bone to examine the dependence of scatter fraction on the density of the scatterer.

  8. The trigger of the ALICE dimuon arm architecture and detectors

    CERN Document Server

    Arnaldi, R; Barret, V; Bastid, N; Blanchard, G; Chiavassa, E; Cortese, P; Crochet, Philippe; Dellacasa, G; De Marco, N; Dupieux, P; Espagnon, B; Fargeix, J; Gallio, M; Lamoine, L; Luquin, Lionel; Manso, F; Métivier, V; Musso, A; Piccotti, A; Rahmani, A; Ramillien, V; Royer, L; Roig, O; Scalas, E; Scomparin, E; Vercellin, Ermanno

    1999-01-01

    The trigger system of the ALICE dimuon arm is based on resistive plate chambers (RPC). Besides a short description of the trigger system, the test results of a RPC prototype with electrodes made of low resistivity bakelite ( equivalent to 3.10/sup 9/ Omega .cm) are presented. Rate capability, time resolution and cluster size have been measured for the RPC operated both in streamer and in avalanche mode. Although the rate capability is obviously higher in avalanche mode (few kHz/cm/sup 2/), remarkable results have been achieved even in streamer mode (several hundreds of Hz/cm/sup 2/). (6 refs).

  9. A low-resistivity RPC for the ALICE dimuon arm

    International Nuclear Information System (INIS)

    In view of ALICE, the dedicated Heavy-Ion Experiment at LHC, a Resistive Plate Chamber (RPC) with electrodes made of low-resistivity bakelite (ρ≅3.5x109 Ω cm) has been tested at the CERN SPS both in streamer and in avalanche mode. The chamber has shown a stable behaviour and excellent rate capability: its efficiency is better than 95% for local particle fluxes of about 1 and 10 kHz/cm2 for operation in streamer and in avalanche mode, respectively. The cluster size and the time resolution have also been measured for both modes of operation

  10. 1. Airborne 2. Hangár

    OpenAIRE

    Johnson, Christy

    2008-01-01

    Hangár, Bakelit Multi Art Center 7th L1 Dance Festival, Budapest, Hungary Installation, 2008 AIRBORNE (projection-sound-monitor installation) was sited in the Hangár, B.A.C. as part of the 7th L1 Dance Festival in Budapest, Hungary (March 2008). This work continues Johnson's interest in and use of 'found' material (16mm wind tunnel footage), and performative methods (sound recording of Channel 9 on United Airlines). This immersive work explores the turbulence of suspension and sets ...

  11. Highly efficient resistive plate chambers for high rate environment

    International Nuclear Information System (INIS)

    The full scale prototype of an Inverted Double Gap RPC module for ME-1/1 station of the CMS detector was tested in the Gamma Irradiation Facility at the CERN SPS muon beam. The chamber made of medium resistivity bakelite and filled with 'green gas' mixture of C2H2F4/iso-butane/SF6 has wide efficiency plateau and good timing properties when operated in avalanche mode under continuous irradiation with strong 137Cs source for rates up to about 5 kHz/cm2/gap

  12. Organic Fingerprint Powders Based on Fluorescent Phloxine B Dye.

    Directory of Open Access Journals (Sweden)

    G. S. Sodhi

    2000-04-01

    Full Text Available Novel fingerpript powders based on organic dye (phJoxine B have been prepared using insoluble salts as adhesive matrials in place of costly resinous polymers (which most conventional powders incorporate. Sharp and clear prints have been developed on a wide range of surfaces, such as paper, I plastic, glass, bakelite, enamelled metal and polished wood. The fluorescent nature of phloxine B assists in developing weak prints und.er ultraviolet light which can assist a forensic scientist for lifting  fingerprints frqm the scene of crime and also a defence scientist for establishing the identity of deceased native soldiers as well as of prisoners of war.

  13. An Improved Technique for the Preparation of Mounted or Unmounted Carbon/Epoxy Specimens

    Science.gov (United States)

    Edahl, Robert A., Jr.

    2007-01-01

    As carbon/epoxy materials became more prevalent in the aerospace industry, microstructural analysis demanded specimen preparation techniques that led to better polished surfaces, achievable in a shorter time, and using fewer steps. The desire to use image analysis for material characterization also helped drive the goal for defect free surfaces. At NASA-Langley (LaRC), carbon/epoxy specimens had been historically prepared in 1 inch diameter Bakelite mounts. Carbon/epoxy specimens that were 1/8 to 1/4 inch thick were not affected by the heat and pressure required for mounting in Bakelite, however thinner specimens were crushed during mounting. A two-part room temperature curing epoxy was chosen as an alternative but sometimes voids developed between the specimen and the mounting material. This was prevented by either heating the epoxy to 140 degrees F to lower the viscosity of the epoxy or by using a vacuum impregnation apparatus. Both techniques helped facilitate flow and allowed the epoxy to penetrate crevices.

  14. Beam test results of CMS RPCs at high eta region under high-radiation environment

    CERN Document Server

    Park, S; Bahk, S Y; Hong, B; Hong, S J; Kang, D H; Kang, T I; Kim, T J; Kim, Y J; Kim, Y U; Koo, D G; Lee, H W; Lee, K S; Lee, S J; Lim, J K; Moon, D H; Nam, S K; Oh, J K; Park, W J; Rhee, J T; Ryu, M S; Shim, H H; Sim, K S

    2004-01-01

    The Compact Muon Solenoid (CMS) forward resistivity plate chambers (RPCs) at the high eta region must be operated in presence of a radiation-induced rate as high as 1 kHz/cm**2. It is still unknown if the RPCs coated with linseed oil can be operated under such a high- radiation environment over the lifetime of CMS. Non-oiled RPCs may be one of the options since phenolic or melamine-coated bakelite is chemically stabler than linseed oil. We have constructed oiled and non-oiled RPCs at the high eta region of CMS using phenolic bakelite and tested them in the Gamma Irradiation Facility at CERN. While both RPCs show the same characteristics in the efficiency and the strip multiplicity, the non-oiled RPC generates an intrinsic noise rate of 50 Hz/cm**2, compared to only 5 Hz/cm**2 for the oiled RPC, both at 10.0kV which is about 100 V above the 95% knee of the efficiency curve.

  15. A new type of RPC for the VETO of JUNO

    Science.gov (United States)

    Xie, B.; Wang, Y.; Guo, B.; Zhu, W.; Li, Y.; Cheng, J.

    2014-10-01

    The capability of covering very large areas at low cost, besides showing excellent performance in many aspects, motivated the application of RPCs to Neutrino physics research in experiments such as Daya Bay neutrino experiment. However, some of the traditional bakelite RPCs cannot work well in these hash underground environments. This paper mainly describes a new type of RPC for the VETO detector of JUNO. It is developed with thin float glass, and a special necklace spacer is designed to keep the gap uniformity. The RPC is sealed in a gas tight box, so it will not be affected directly by ambient environment and it can work well in humid condition underground. A one-dimensional and a two-dimensional readout RPC prototypes have been developed and tested in our lab. The results show that the detection efficiency can reach as high as 98% and the noise rate is less than 1 Hz/cm2 both in the avalanche mode and streamer mode. The dark current is much lower than the traditional Bakelite RPC. Some details of the structure and performance of the new type of RPC are all described in this paper.

  16. Development and characterization of single gap glass RPC

    CERN Document Server

    Manisha,; Shahi, J S; Singh, J B

    2016-01-01

    The India-based Neutrino Observatory (INO) collaboration is going to build a 50 kton magnetized Iron CALorimeter (ICAL) detector for the precise measurement of neutrino oscillations using atmospheric neutrinos. The proposed ICAL detector will be a stack of magnetized iron plates (acting as target material) interleaved with the glass Resistive Plate Chambers (RPCs)as active elements. RPC is a gaseous detector made up of two parallel electrodes having high bulk resistivity like that of the float glass and bakelite. For ICAL detector, glass is preferred over bakelite as it does not need any kind of surface treatment to achieve better surface uniformity and also the cost of detector is reduced. Under detector R&D efforts for the proposed detector, we have fabricated the glass RPCs of 1m X 1m in size procuring glass of ~ 2 mm thickness from one of the Indian glass manufacturers (Asahi). In the present characterization studies, we report on the leakage current, pulse width optimization for the measurements of e...

  17. Long-term operation test of RPCs for the OPERA experiment

    CERN Document Server

    Barichello, G; Brugnera, R; Candela, A; Carrara, E; D'Incecco, M; Dal Corso, F; Degli Esposti, L; Dusini, S; Garfagnini, A; Gustavino, C; Lindozzi, M; Mengucci, A; Monacelli, P; Paoloni, A; Spinetti, M; Stanco, L; Terranova, F; Ventura, M; Votano, L

    2004-01-01

    OPERA is one of the two detectors foreseen in the CERN Neutrino to Gran Sasso project, devoted to the detection of nu//mu into nu //tau oscillations in the parameter region suggested by SuperKamiokande data on atmospheric neutrinos. Bakelite RPCs will be used to instrument the iron yoke of the muon spectrometers. We present the results of long-term (greater than 6 months) streamer operations of real size OPERA RPCs at cosmic rays fluxes. Given the very low rate observed in the underground Gran Sasso Laboratories, under 3 km w.e., even this short time period is equivalent to more than 10 OPERA years. Results of tests with different gas mixtures are reported, in view of decreasing the streamer charge of operation for the RPCs employed in the experiment.

  18. Effect of sample thickness on the measured mass attenuation coefficients of some compounds and elements for 59.54, 661.6 and 1332.5 keV gamma-rays

    CERN Document Server

    El-Rahman, M A; Abdel-Hady, Y L; Kamel, N

    2000-01-01

    Measurements have been made to determine gamma-rays attenuation coefficients very accurately by using an extremely narrow-collimated-beam transmission method. The effect of the sample thickness on the measured values of the mass attenuation coefficients (mu/rho) cm sup 2 /g of perspex, bakelite, paraffin, Al, Cu, Pb and Hg have been investigated at three different gamma-ray energies (59.54, 661.6 and 1332.5 keV). It is seen that for these chosen materials (mu/rho) remains constant in good agreement with the theoretical values up to 3 mean free paths and after that (mu/rho) values for Cu, Pb and Hg decrease with further increase in the absorber thickness. This result may be attributed to the increase in the number of coherent small-angle scattering photons which reach the detector.

  19. Aging tests and chemical analysis of Resistive Plate Chambers for the trigger of the ALICE dimuon arm

    CERN Document Server

    Arnaldi, R; Colla, A; Cortese, P; Dellacasa, G; De Marco, N; Ferretti, A; Gallio, M; Guernane, R; Mereu, P; Musso, A; Oppedisano, C; Piccotti, A; Poggio, F; Scomparin, E; Sigaudo, F; Travaglia, G; Vercellin, E; Yermia, F

    2004-01-01

    Resistive Plate Chambers operated in streamer mode have been chosen as trigger detectors for the forward dimuon spectrometer of the ALICE experiment. During tests performed at CERN PS, small size prototypes with low-resistivity bakelite electrodes and with a strongly quenched gas mixture have shown the required rate capability, tracking and timing properties. Present efforts are devoted to the study of the detector performance after long irradiation periods. In this paper, a summary of the results of aging tests performed at the Gamma Irradiation Facility at CERN will be presented. Detectors show quite stable performance up to about 50mC/cm**2, as the requirements for 10 years operation, program at LHC including a safety factor of 2. Afterwards, we observed an increase of the dark current not associated with an increase of the counting rate. We also report results of chemical analysis carried out by different CERN teams on exhaust gases and electrode surfaces of the detectors after aging.

  20. Method of measuring dielectric constant using an oscilloscope

    Science.gov (United States)

    Nogi, Yasuyuki; Watanabe, Masayuki; Suzuki, Kiyomitsu; Ohkuma, Yasunori

    2015-09-01

    A simple relationship determining the dielectric constant of a material inserted in a parallel-plate capacitor is formulated from Gauss's law for a uniform electric field and the continuity condition of electric flux at the boundary of the material. The relationship suggests that the dielectric constant can be determined from the dependence of the charge stored on the capacitor on the thicknesses of the material and the air layer between the plates. A uniform field is created by applying an ac voltage to the plates, which includes a guard ring. The stored charge is estimated by using an oscilloscope to measure the voltage across a resistor inserted between the power supply and the capacitor. The results of the measurement are given for planar materials such as soda-lime glass, Bakelite, acrylic glass, and Teflon with a thickness of 0.5-1 cm.

  1. Performance and simulation of a double-gap resistive plate chamber in the avalanche mode

    CERN Document Server

    Ahn Sung Hwan; Hong Byung Sik; Hong Seong Jong; Ito, M; Kang, T I; Kim, B I; Kim, J H; Kim, Y J; Kim, Y U; Koo, D G; Lee Hyup Woo; Lee, K B; Lee Kyong Sei; Lee Seok Jae; Lim, J K; Moon, D H; Nam, S K; Park, S; Park, W J; Rhee June Tak; Ryu, M S; Sim Kwang Souk

    2004-01-01

    We present a detailed analysis of the time and the charge signals of a prototype double-gap resistive plate chamber for the endcap region of the Compact Muon Solenoid (CMS) detector at the Large Hadron Collider (LHC). The chamber was built with relatively low-resistivity bakelite. The time and the charge results demonstrate that the high- voltage plateau, which satisfies various CMS requirements for the efficiency, the noise cluster rate, the fraction of the large signal, and the streamer probability, can be extended at least up to 400 V with the present design. In addition, a simple avalanche multiplication model is studied in detail. The model can reproduce the experimental charge spectra reasonably well. The charge information enables us to estimate the effective Townsend coefficient in avalanche-mode operation.

  2. Study of cosmic ray muons tracks recorded by prototype ICAL (Kolkata): Zenith angle distribution

    International Nuclear Information System (INIS)

    The India-based Neutrino Observatory (INO) collaboration is moving fast towards setting up a magnetized Iron CALorimeter (ICAL) to study atmospheric neutrinos and to determine the neutrino oscillation parameters with high precision. In final phase ICAL uses 50 kton Iron as target mass and ∼ 30000 glass Resistive Plate Chambers (RPC) having dimension 2m x 2m x 0.002m and 4m x 2m x 0.002m as active detector elements. A prototype RPC detector stack comprising 12 layers of RPCs of glass and bakelite having area 1m x 1m is in continuous operation with and without magnetic field having strength 1.5 Tesla for the last two years. We present here the recent results of the studies performed with this experimental set up

  3. Study of the impact of environmental parameters on the operation of CMS RPCs

    CERN Document Server

    Assran, Yasser

    2011-01-01

    CMS (Compact Muon Solenoid) is a general purpose detector designed to run at the highest luminosity at Large Hadron Collider (LHC), CERN, Geneva, Switzerland. The muon system of the CMS experiment relies on Drift Tubes (DT), Cathode Strip Chambers (CSC) and Resistive Plate Chambers (RPC). RPCs are dedicated for the first level muon trigger and they are characterized by bakelite electrodes delimited in a specialized gas volume filled with operational gas mixture. This analysis has been done for the RPC chambers installed in CMS experiment at CERN. The Currents of CMS RPCs chambers are analyzed as a function of environmental parameters such as Temperature, Humidity and pressure, which are important for the operation of the muon detector system. A novel Neural Network approach has been used to analyze the data and to build a model using experimental measurements and combining the results of the simulations. Data from RPC Chambers in CMS experiment are taken and compared to the results from neural Network.

  4. The Monitor online system of the OPERA muon magnetic spectrometer

    CERN Document Server

    Ugolino, U.; Acquafredda, R.; Masone, v.

    2008-01-01

    The OPERA muon magnetic spectrometer has been designed for muon detection, tracking and timing. The 44 bakelite Resistive Chambers (RPC) planes, imbibed inside the magnet iron slabs, must provide the tracking of the muon curved in the magnetic field to ease the momentum and charge measurement provided by the HPT. Furthermore, it provides the momentum for muons stopping in the iron. RPC signals will be also used as start of drift tube acquisition thanks to the very good time resolution of RPC detectors. Due to the required performances the tracking detector must be fully efficient and stable. In this conditions an online monitor is mandatory to continuously control stability of run conditions. We report the main characteristics and performances of the monitor system for the OPERA spectrometer and capabilities of the software developed for settings and data acquisition.

  5. The BaBar instrumented flux return performance: lessons learned

    CERN Document Server

    Anulli, F; Baldini, R; Band, H R; Bionta, R; Brau, J E; Brigljevic, V; Buzzo, A; Calcaterra, A; Carpinelli, M; Cartaro, C; Cavallo, N; Crosetti, G; De Nardo, Gallieno; De Sangro, R; Eichenbaum, A; Fabozzi, F; Falciai, D; Ferrarotto, F; Ferroni, F; Finocchiaro, G; Forti, F; Frey, R; Gatto, C; Graug; Iakovlev, N I; Iwasaki, M; Johnson, J R; Lange, D J; Lista, L; Lo Vetere, M; Lü, C; Macri, M; Messner, R; Moore, T B; Morganti, S; Neal, H; Neri, N; Palano, A; Paoloni, E; Paolucci, P; Passaggio, S; Pastore, F C; Patteri, P; Peruzzi, I; Piccolo, D; Piccolo, M; Piredda, G; Robutti, E; Roodman, A; Santroni, A; Sciacca, C; Sinev, N B; Soha, A; Strom, D; Tosi, S; Vavra, J; Wisniewski, W J; Wright, D M; Xie, Y; Zallo, A

    2002-01-01

    The BaBar Collaboration has operated an instrumented flux return (IFR) system covering over 2000 m sup 2 with resistive plate chambers (RPCs) for nearly 3 years. The chambers are constructed of bakelite sheets separated by 2 mm. The inner surfaces are coated with linseed oil. This system provides muon and neutral hadron detection for BaBar. Installation and commissioning were completed in 1998, and operation began mid-year 1999. While initial performance of the system reached design, over time, a significant fraction of the RPCs demonstrated significant degradation, marked by increased currents and reduced efficiency. A coordinated effort of investigations have identified many of the elements responsible for the degradation. This article presents our current understanding of the aging process of the BaBar RPCs along with the action plan to combat performance degradation of the IFR system.

  6. Laser beam characterization of the ATLAS RPC gas mixture

    Energy Technology Data Exchange (ETDEWEB)

    Chiodini, G. [INFN Lecce, via per Arnesano, 73100 Lecce (Italy); Coluccia, M.R.; Gorini, E. [INFN Lecce, via per Arnesano, 73100 Lecce (Italy); Dipartimento di Fisica, Universita degli Studi di Lecce, via per Arnesano, 73100 Lecce (Italy); Grancagnolo, F.; Primavera, M. [INFN Lecce, via per Arnesano, 73100 Lecce (Italy)

    2007-10-15

    A measurement of the electrons drift velocity in C{sub 2}H{sub 2}F{sub 4}-based gas mixture has been performed and results have been compared with calculations. Primary ionization is induced in the gas via double photon ionization process by mean of a pulsed Nitrogen laser. The results of the drift velocity, obtained at room temperature and normal pressure, are presented as a function of the electric field strength. To perform the measurements we used a small sized RPC prototype with a 2 mm gas gap delimited by 2mm-thick linseed-oil-treated bakelite plates with resistivity of about 1.71x10{sup 10}{omega} cm at 20{sup o}C.

  7. Laser beam characterization of the ATLAS RPC gas mixture

    International Nuclear Information System (INIS)

    A measurement of the electrons drift velocity in C2H2F4-based gas mixture has been performed and results have been compared with calculations. Primary ionization is induced in the gas via double photon ionization process by mean of a pulsed Nitrogen laser. The results of the drift velocity, obtained at room temperature and normal pressure, are presented as a function of the electric field strength. To perform the measurements we used a small sized RPC prototype with a 2 mm gas gap delimited by 2mm-thick linseed-oil-treated bakelite plates with resistivity of about 1.71x1010Ω cm at 20oC

  8. Optimisation and Characterisation of Glass RPC for India-based Neutrino Observatory Detectors

    CERN Document Server

    Kanishka, R; Indumathi, D

    2016-01-01

    The proposed magnetised Iron CALorimeter detector (ICAL) to be built in the India-based Neutrino Observatory (INO) laboratory aims to detect atmospheric muon neutrinos. In order to achieve improved physics results, the constituent components of the detector must be fully understood by proper characterisation and optimisation of various parameters. Resistive Plate Chambers (RPCs) are the active detector elements in the ICAL detector and can be made of glass or bakelite. The number of RPCs required for this detector is very large number so a detailed R & D is necessary to establish the characterisation and optimisation of these RPCs. These detectors once installed will be taking data for 15-20 years. In this paper, we report the selection criteria of glass used of various Indian manufacturers such as Asahi, Saint Gobain and Modi. Based on the factors like aging that deteriorate the quality of glass the choice is made. The glass characterisation studies include UV-VIS transmission for optical properties, SEM...

  9. Performance of a large forward resistive plate chamber for the CMS /LHC under high radiation environment

    CERN Document Server

    Ahn, S H; Bahk, S Y; Hong, B; Hong, S J; Kim, K H; Kim, Y J; Kim, Y U; Koo, D G; Lee, K S; Lee, S J; Nam, S K; Park, S; Rhee, J T; Seo, S W; Sim, K S

    2001-01-01

    We present the first beam test results of a real size prototype RPC for the endcap region of the CMS, one of large detectors at CERN LHC. The chamber was built with relatively low resistivity bakelite made in Korea and was operated successfully at the Gamma Irradiation Facility at CERN under the highest photon flux available, which corresponds to an effective cluster rate up to about 800 Hz/cm/sup 2 /. The cross-talk effects between strips and sectors have been studied extensively. The high voltage plateau, which satisfies the CMS requirements for efficiency and the number of strips fired per cluster, extends to at least 300 V. The time resolution has been measured to be better than 1.3 ns in this HV plateau region. These results demonstrate that the current design of the device can be used as a muon trigger detector for the CMS forward region. (13 refs).

  10. Heat Transfer Augmentation in Developing Flow Through a Ribbed Square Duct

    Institute of Scientific and Technical Information of China (English)

    Khan R K; Ali M.A.T; Akhanda M.A.R

    2006-01-01

    An experimental study is conducted to investigate the heat transfer augmentation in developing turbulent flow through a ribbed square duct. The duct is made of 16mm thick bakelite sheet. The bottom surface of the ribbed wall having rib pitch to height ratio of 10 is heated by passing a c current to the heater placed under it. The uniform heating is controlled using a digital temperature controller and a variac. The results of ribbed duct are compared with the results of a smooth duct under the same experimental conditions. It is observed that the heat transfer augmentation in ribbed duct is better than that of the smooth duct. At Re=5.0 × 104 , the mean temperature of air flowing through the ribbed duct increases by 2.45 percent over the smooth duct, whereas in the ribbed duct Nusselt number increases by 15.14 percent than that of the smooth duct with a 6 percent increase in pressure drop.

  11. Beam test results of the first full-scale prototype of CMS RE 1/2 Resistive Plate Chamber

    CERN Document Server

    Ying, Jun; Cai Jian Xin; Liu Hong Tao; Qian Si Jin; Wang Quan Jin; Ye Yan Lin

    2005-01-01

    We reported the muon beam test results of the first full-scale prototype of CMS RE 1/2 Resistive Plate Chamber (RPC). The bakelite surface is treated using a special technology without oil to make it smooth enough. The full scale RE 1/2 RPC with honeycomb supporting frame is strong and thin enough to be fitted to the limited space of CMS design for the inner Forward RPC. The muon beam test was performed at CERN Gamma Irradiation Facility (GIF). The detection efficiency of this full scale RPC prototype is >95% even at very high irradiation background. The time resolution (less than 1.2 ns) and spatial resolution are satisfactory for the muon trigger device in future CMS experiments. The noise rate is also calculated and discussed.

  12. [Surgical technique of displacement and retraction of the heart with a pigtail shaped hook and Tentacles Heart Positioner].

    Science.gov (United States)

    Shimamura, Yoshiei; Mochizuki, Y; Yamada, Y; Eda, K; Shibasaki, I; Inoue, Y; Miyoshi, S

    2007-07-01

    We describe a novel heart retracting system with Tentacles Heart Positioner (Sumitomo Bakelite, Tokyo) during off-pump coronary artery bypass grafting (OPCAB). The heart retracting system is composed of a pigtail shaped hook attached to a flexible Universal Stabilizer Arm (Estech, Minneapolis). After Tentacles suction device is applied on the surface of the heart, the retracting system is fixed on the sternal retracter so that the hook can hang and support the retracting tubes of the sucker. By regulating the shape of the Universal Stabilizer Arm and the position of the hook, the retracting system can lift the heart sufficiently and maintain the optimal position of the heart during OPCAB procedure. Together with Tentacles Heart Positioner, the heart retracting system provides excellent exposure of target coronary arteries with minimal effect on hemodynamics.

  13. Performance simulation of a MRPC-based PET Imaging System

    CERN Document Server

    Banerjee, A

    2011-01-01

    The low cost and high resolution gas-based Multi-gap Resistive Plate Chamber (MRPC) opens a new possibility to find an efficient alternative detector for Time of Flight (TOF) based Positron Emission Tomography, where the sensitivity of the system depends largely on the time resolution of the detector. Suitable converters can be used to increase the efficiency of detection of photons from annihilation. In this work, we perform a detailed GEANT4 simulation to optimize the converter thickness thereby improving the efficiency of photon conversion. Also we have developed a Monte Carlo based simulation of MRPC response thereby obtaining the intrinsic time resolution of the detector, making it possible to simulate the final response of MRPC-based systems for PET imaging. The result of the cosmic ray test of a four-gap Bakelite-based MRPC operating in streamer mode is discussed.

  14. Ageing tests on the low-resistivity RPC for the ALICE dimuon arm

    CERN Document Server

    Arnaldi, R; Barret, V; Bastid, N; Blanchard, G; Chiavassa, E; Cortese, P; Crochet, Philippe; De Marco, N; Dellacasa, G; Drancourt, C; Dupieux, P; Espagnon, B; Ferretti, A; Forestier, B

    2003-01-01

    The trigger for the Dimuon Forward Spectrometer of the forthcoming ALICE experiment at CERN LHC will be provided by low-resistivity, single gap Resistive Plate Chambers working in streamer mode. Different ageing test were performed to measure and improve the life- time of the detector. Dummy chambers have been built to understand the effects of continuous gas flow upon the Bakelite resistivity: the results concerning our standard gas mixture (49% Ar, 40% forane, 7% isobutane and 4% SF//6) are reported, and compared with the same mixture in which similar to 1% of water vapor is added. Moreover, two ageing test of 1 month each have been carried out at the Gamma Irradiation Facility at CERN during 2001. The efficiency for cosmic rays under gamma irradiation of RPCs coated with different thicknesses of linseed oil was measured. After protracted operation, the detectors have shown an increase of the current and of the background rate. The increase is slower in the chamber with a thicker oil coating.

  15. Effective atomic numbers of some H-, C-, N- and O-based composite materials derived from differential incoherent scattering cross-sections

    Indian Academy of Sciences (India)

    S Prasanna Kumar; V Manjunathaguru; T K Umesh

    2010-04-01

    In this work, we have made an effort to determine whether the effective atomic numbers of H-, C-, N- and O-based composite materials would indeed remain a constant over the energy grid of 280–1200 keV wherein incoherent scattering dominates their interaction with photons. For this purpose, the differential incoherent scattering cross-sections of Be, C, Mg, Al, Ca and Ti were measured for three scattering angles 60°, 80° and 100° at 279.1, 661.6 and 1115.5 keV using which an expression for the effective atomic number was derived. The differential incoherent scattering cross-sections of the composite materials of interest measured at these three angles in the same set-up and substituted in this expression would yield their effective atomic number at the three energies. Results obtained in this manner for bakelite, nylon, epoxy, teflon, perspex and some sugars, fatty acids as well as amino acids agreed to within 2% of some of the other available values. It was also observed that for each of these samples, eff was almost a constant at the three energies which unambiguously justified the conclusions drawn by other authors earlier [Manjunathaguru and Umesh, J. Phys. B: At. Mol. Opt. Phys. 39, 3969 (2006); Manohara et al, Nucl. Instrum. Methods B266, 3906 (2008); Manohara et al Phys. Med. Biol. 53, M377 (2008)] based on total interaction cross-sections in the energy grid of interest.

  16. Final results of the tests on the resistive plate chambers for the ALICE muon arm

    Energy Technology Data Exchange (ETDEWEB)

    Arnaldi, R. [INFN, Sezione di Torino (Italy); Baldit, A.; Barret, V.; Bastid, N.; Blanc, A.; Blanchard, G. [LPC Clermont Ferrand, IN2P3/CNRS, Universite Blaise Pascal (France); Chiavassa, E. [INFN, Sezione di Torino (Italy); Dipartimento di Fisica Sperimentale dell' Universita di Torino (Italy); Cortese, P. [INFN, Sezione di Torino (Italy); Dipartimento di Scienze e Tecnologie, Avanzate dell' Universita del Piemonte Orientale (Italy); Crochet, P. [LPC Clermont Ferrand, IN2P3/CNRS, Universite Blaise Pascal (France); Dellacasa, G. [INFN, Sezione di Torino (Italy); Dipartimento di Scienze e Tecnologie, Avanzate dell' Universita del Piemonte Orientale (Italy); De Marco, N. [INFN, Sezione di Torino (Italy); Devaux, A.; Dupieux, P. [LPC Clermont Ferrand, IN2P3/CNRS, Universite Blaise Pascal (France); Ferretti, A.; Gallio, M. [INFN, Sezione di Torino (Italy); Dipartimento di Fisica Sperimentale dell' Universita di Torino (Italy); Gemme, R. [INFN, Sezione di Torino (Italy); Dipartimento di Scienze e Tecnologie, Avanzate dell' Universita del Piemonte Orientale (Italy); Grygorian, S.; Insa, C.; Jouve, F.; Lopez, X. [LPC Clermont Ferrand, IN2P3/CNRS, Universite Blaise Pascal (France)] (and others)

    2009-05-01

    The trigger for the ALICE muon spectrometer will be issued by single-gap, low resistivity bakelite resistive plate chambers (RPCs). The trigger system consists of four 5.5x6.5m{sup 2} RPC planes arranged in two stations, for a total of 72 detectors. One hundred and sixteen detectors have been assembled and tested in Torino. The tests have been performed with the streamer mixture developed for heavy ion data-taking. The tests include: the detection of gas leaks and parasitic currents; the measurement of the efficiency with cosmic rays, with particular regard to the uniformity of the efficiency throughout the whole active surface, with a granularity of about 2x2cm{sup 2}; the measurement of the dark current and of the mean and localised noise rate. All the RPCs produced have been characterised. Among them, the detectors to be finally installed in ALICE and some spare have been selected; 17% of all the produced detectors have been discarded. A short description of the test set-up is given. The results of the tests are presented, with particular regard to the performance of the selected detectors.

  17. Operation of low-noise single-gap RPC modules exposed to ionisation rates up to 1 kHz/cm$^{2}$

    CERN Document Server

    Cwioka, M; Górski, M; Królikowski, J; 10.1016/j.nima.2004.06.123

    2004-01-01

    Two single gap medium-size RPC modules, made of bakelite plates of very good mechanical quality of the surface and having initial volume resistivity of 1 * 10/sup 10/ Omega cm, were tested in the Gamma Irradiation Facility at CERN at ionisation rates up to 1 kHz/cm/sup 2 /. The internal surfaces facing the gas volume of one RPC module were cladded with a thin layer of linseed oil varnish for comparison of oiled and non-oiled RPC operation. The results refer to the gas mixture of C/sub 2/H/sub 2/F/sub 4//isobutane (97:3) with SF/sub 6/ addition below 1%. The single gap modules exhibited full detection efficiency plateau for the high voltage range of about 1 kV at full intensity of gamma rays. Good timing characteristics allowed to reach 95% efficiency at fully opened irradiation source with time window of 20 ns. The intrinsic noise rate for a non-oiled and an oiled RPC gap was, respectively, below 5 and 1 Hz/cm/sup 2/ at full efficiency over 1 kV voltage range.

  18. Ageing tests on the low-resistivity RPC for the ALICE dimuon arm

    International Nuclear Information System (INIS)

    The trigger for the Dimuon Forward Spectrometer of the forthcoming ALICE experiment at CERN LHC will be provided by low-resistivity, single gap Resistive Plate Chambers working in streamer mode. Different ageing test were performed to measure and improve the life-time of the detector. Dummy chambers have been built to understand the effects of continuous gas flow upon the Bakelite resistivity: the results concerning our standard gas mixture (49% Ar, 40% forane, 7% isobutane and 4% SF6) are reported, and compared with the same mixture in which ∼1% of water vapor is added. Moreover, two ageing test of 1 month each have been carried out at the Gamma Irradiation Facility at CERN during 2001. The efficiency for cosmic rays under γ irradiation of RPCs coated with different thicknesses of linseed oil was measured. After protracted operation, the detectors have shown an increase of the current and of the background rate. The increase is slower in the chamber with a thicker oil coating

  19. MUON DETECTORS: RPC

    CERN Multimedia

    P. Paolucci

    2013-01-01

    During LS1, the Resistive Plate Chamber (RPC) collaboration is focusing its efforts on installation and commissioning of the fourth endcap station (RE4) and on the reparation and maintenance of the present system (1100 detectors). The 600 bakelite gaps, needed to build 200 double-gap RE4 chambers are being produced in Korea. Chamber construction and testing sites are located at CERN, in Ghent University, and at BARC (India). At present, 42 chambers have been assembled, 32 chambers have been successfully tested with cosmic rays runs and 7 Super Modules, made by two chambers, have been built at CERN by a Bulgarian/Georgian/Italian team and are now ready to be installed in the positive endcap. The 36 Super Modules needed to complete the positive endcap will be ready in September and installation is scheduled for October 2013. The Link-Board system for RE4 is under construction in Naples. Half of the system has been delivered at CERN in June. Six crates (Link-Board Boxes) and 75 boards, needed to instrument t...

  20. 连续玄武岩纤维增强复合材料的抗弹性能研究%THE BALLISTIC PERFORMANCE OF COMPOSITES REINFORCED BY CONTINUOS BASALT FIBER

    Institute of Scientific and Technical Information of China (English)

    李英建; 李峰; 曲英章; 金子明

    2011-01-01

    By researching the ballistic performance of epoxy / continuous basalt fiber ( CBF ), viynyl ester/CBF, polyurethane / CBF and bakelite / CBF, it was found that the ballistic performance of viynyl ester/CBF was optimal.The relationship between thickniss and narmal angle of composites and ballistic performance was researched. In the end, the analysis of ballistic mechanism of CBF reinforced composites was given.%通过研究环氧树脂/连续玄武岩纤维( CBF)、乙烯基酯树脂/CBF、聚氨酯树脂/CBF、酚醛树脂/CBF体系的抗弹性能,发现CBF增强乙烯基酯复合材料的抗弹性能较好.考察了CBF增强乙烯基酯树脂复合材料厚度、靶板法线角对抗弹性能的影响,并对CBF增强复合材料的抗弹机理进行了分析.

  1. The Muon Spectrometer Barrel Level-1 Trigger of the ATLAS Experiment at LHC

    CERN Document Server

    Aloisio, A; Conventi, F; De Asmundis, R; Izzo, V; Migliaccio, A; Ciapetti, G; Di Mattia, A; Luci, C; Luminari, L; Nisati, A; Pastore, F; Petrolo, E; Vari, R; Veneziano, Stefano; Salamon, A

    2006-01-01

    The proton-proton beam crossing at the LHC accelerator at CERN will have a rate of 40 MHz at the project luminosity. The ATLAS Trigger System has been designed in three levels in order to select only interesting physics events reducing from that rate of 40 MHz to the foreseen storage rate of about 200 Hz. The First Level reduces the output rate to about 100 kHz. The ATLAS Muon Spectrometer has been designed to perform stand-alone triggering and measurement of muon transverse momentum up to 1 TeV/c with good resolution (from 3% at 10 GeV/c up to 10% at 1 TeV/c). In the Barrel region of the Muon Spectrometer the Level-1 trigger is given by means of three layers of Resistive Plate Chamber detectors (RPC): a gaseous detector working in avalanche mode composed by two plates of high-resistivity bakelite and two orthogonal planes of read-out strips. The logic of the Level-1 barrel muon trigger is based on the search of patterns of RPC hits in the three layers consistent with a high transverse momentum muon track ori...

  2. Biomorphous SiC ceramics prepared from cork oak as precursor

    Science.gov (United States)

    Yukhymchuk, V. O.; Kiselov, V. S.; Valakh, M. Ya.; Tryus, M. P.; Skoryk, M. A.; Rozhin, A. G.; Kulinich, S. A.; Belyaev, A. E.

    2016-04-01

    Porous ceramic materials of SiC were synthesized from carbon matrices obtained via pyrolysis of natural cork as precursor. We propose a method for the fabrication of complex-shaped porous ceramic hardware consisting of separate parts prepared from natural cork. It is demonstrated that the thickness of the carbon-matrix walls can be increased through their impregnation with Bakelite phenolic glue solution followed by pyrolysis. This decreases the material's porosity and can be used as a way to modify its mechanical and thermal characteristics. Both the carbon matrices (resulted from the pyrolysis step) and the resultant SiC ceramics are shown to be pseudomorphous to the structure of initial cork. Depending on the synthesis temperature, 3C-SiC, 6H-SiC, or a mixture of these polytypes, could be obtained. By varying the mass ratio of initial carbon and silicon components, stoichiometric SiC or SiC:C:Si, SiC:C, and SiC:Si ceramics could be produced. The structure, as well as chemical and phase composition of the prepared materials were studied by means of Raman spectroscopy and scanning electron microscopy.

  3. Study of neutron response for two hybrid RPC setups using the GEANT4 MC simulation approach

    Institute of Scientific and Technical Information of China (English)

    M.Jamil; J.T.Rhee; Y.J.Jeon

    2009-01-01

    The present article describes a detailed neutron simulation study in the energy range 10~(-10) MeV to 1.0 GeV for two different RPC configurations.The simulation studies were taken by using the GEANT4 MC code.Aluminum was utilized on the GND and readout strips for the (a) Bakelite-based and (b) glass-based RPCs.For the former type of RPC setup the neutron sensitivity for the isotropic source was S_n=2.702×10~(-2) at E_n=1.0 GeV, while for the latter type of RPC, the neutron sensitivity for the same source was evaluated as S_n=4.049×10~(-2) at E_n=1.0 geV.These results were further compared with the previous RPC configuration in which copper was used for ground and pickup pads.Additionally A1 was employed at (GND+strips) of the phosphate glass RPC setup and compared with the copper-based phosphate glass RPC.Good agreement with sensitivity values was obtained with the current and previous simulation results.

  4. Ultra fast timing MMRPC: a versatile detector for basic and applied science

    International Nuclear Information System (INIS)

    Three decades ago the Resistive Plate Chamber (RPC) was invented to overcome several problems of parallel plate chambers. Unlike parallel plate chambers, electrodes of RPCs are made of resistive material like Bakelite or float glass. This has the effect that only a limited part of the electrode is discharged during the passage of an ionizing particle with subsequent avalanches or streamers, while the rest of the electrode remains unchanged. Wide and/or single gap RPC detectors are used in many large scale experiments to explore various directions of science. This includes fundamental research in particle physics, in astrophysics, in cosmology etc,. In India, RPC detectors array (INO) will play a vital role in the measurement of mass hierarchy of three flavors of neutrino mass. To improve timing resolution, Multigap Resistive Plate Chamber (MRPC) is an intelligent modification of an RPC by increasing the electric field across the gap and creating thinner layers of gas gap by inserting (electrostatically) floating glasses between anode and cathode. It can be shown that a resolution in the range of 50-100 ps is achievable with gaps of 200-300 mm. Moreover, RPCs are insensitive to the magnetic field. Finally timing RPCs have already proved in the last years to be a reliable and stable detector with sensitive larger and regularly used in a large number of experiments

  5. Komposit Laminate Rami Epoksi Sebagai Bahan Alternatif Socket Prosthesis

    Directory of Open Access Journals (Sweden)

    Agustinus P. Irawan

    2009-01-01

    Full Text Available pure plant oil, biofuel, coconut oil, palm oil, jatropha oilSocket is the most important component in a prosthesis making. Performance criteria for prosthetic socket material include strength, durability, minimal weight, comfort, and minimal fabrication cost. This research attempts to analyze the strength of ramie fiber reinforced epoxy laminate composite as an alternative of socket prosthesis. The research based on ASTM D 3039/D 3039M for tensile strength and ASTM D 695 for compressive strength. The ramie fiber used was a continuous fiber 100 % Ne14'S, with Epoxy Resin Bakelite EPR 174 and Epoxy Hardener V-140. The sample test was created using a hand lay-up method. The result of this research is presented in a correlation of finsile strength (st, compression strength (sc, elasticity modulus (E versus fraction volume of fiber (Vf. The result is then being compared with some of the prosthesis material’s strength produced by Otto Bock. The analysis was completed with the mode of the failure observation by using Scanning Electron Microscope (SEM. The result concludes that the ramie fiber reinforced epoxy laminate composite is potentially developed further as a socket prosthesis material on Vf 40 – 50 %. Tensile strength and specific strength that has been generated was higher than that of several materias for socket prosthesis, including fiberglass. The mode of the failure found were a brittle failure on Vf: 10-30%, debonding and delamination on Vf: 40-50%. Abstract in Bahasa Indonesia: Socket merupakan bagian terpenting dalam pembuatan prosthesis. Kriteria bahan socket prosthesis antara lain kekuatan, ketahanan, ringan, kenyamanan dan biaya produksi yang rendah. Penelitian ini bertujuan menganalisis kekuatan komposit laminate berpenguat serat rami epoksi sebagai bahan alternatif socket prosthesis. Pengujian kekuatan mengacu standar ASTM D 3039/D 3039M uji tarik dan ASTM D 695 uji tekan. Serat rami yang digunakan berupa serat kontinyu jenis

  6. 分子蒸馏双酚A环氧树脂的性能研究%Research on the performance of molecular distillation bisphenol- A epoxy resin

    Institute of Scientific and Technical Information of China (English)

    夏宇; 陶纯初; 汝国兴; 张犇

    2012-01-01

    The bisphenol A epoxy resin with trademark JF -9955A was obtained by the molecular distillation of common commercial 128 epoxy resin removed the ligtht distillate and polymer heavy distillate. The JF -9955A was compared with Dow DER 332 and Bakelite EPR 162 high purity bisphenol A epoxy resins by the analysis of FT - IR and liquid chromatography, testings of basic properties and Na + content detection. The product properties of the three epoxy resins cured with anhydride were also tested. The results showed that JF - 9955A had low viscosity, high purity, low contents of hydrolyzable chlorine and other ions. The performance indicators of JF -9955A reached the level of similar foreign products.%采用普通市售128环氧树脂经过分子蒸馏,去除轻馏分和多聚体重组分后,得到双酚A分子环氧树脂,牌号为JF-9955A。通过红外光谱和液相色谱分析,基础性能和Na+含量检测以及对其酸酐固化物性能的测试将JF-9955A与国外陶氏化学的DER 332、BakeliteEPR 162高纯度双酚A环氧树脂进行了对比。结果表明,JF-9955A具有粘度低,纯度高,可水解氯及其他离子杂质含量低等特点,各项性能指标达到国外同类产品水平。

  7. Effective atomic numbers for photon energy absorption of some low-Z substances of dosimetric interest

    International Nuclear Information System (INIS)

    Effective atomic numbers for photon energy absorption (ZPEAeff) and effective atomic numbers for photon interaction (ZPIeff) of some low-Z substances of dosimetric interest such as A-150 tissue-equivalent plastic (A150TEP), alanine, bakelite, Gafchromic sensor (GS), plastic scintillator (PS), polyethylene, mylar, polystyrene, perspex, radiochromic dye film nylon base (RDF : NB), tissue-equivalent gas-methane based (TEG : MB) and tissue-equivalent gas-propane based (TEG : PB) have been calculated by a direct method in the energy region of 1 keV-20 MeV. Experimental mass attenuation coefficients and ZPIeff of some of these substances at selected photon energies of 26.34, 33.2, and 59.54 keV have been obtained and compared with theoretical values. The ZPEAeff and ZPIeff values steadily increases up to 6-15 keV, and then they steadily decrease up to 600-1500 keV for all the substances studied. From 1.5 MeV, the values increases with increase in energy up to 20 MeV. Significant differences up to 33.68% exist between ZPIeff and the ZPEAeff in the energy region of 10-150 keV. The single effective atomic numbers obtained using the program XMuDat (ZXMUDATeff ) are found to be significantly higher compared to those of ZPEAeff and ZPIeff values in the entire energy of interest for all the substances studied. The directly calculated ZPEAeff and ZPIeff values vary with energy compared to the energy-independent effective atomic numbers predicted by various theoretical expressions. The effects of absorption edges on effective atomic numbers and their variation with photon energy and the possibility of defining two set values of effective atomic numbers below the absorption edges of elements present in the composite substances are discussed

  8. A Comparative Study of the Effects of Substrate Composite Materials on External and Internal Handset Antenna EM Absorption

    Directory of Open Access Journals (Sweden)

    Md Ikbal HOSSAIN

    2016-09-01

    Full Text Available Cellular phones are used in the vicinity of a human head, which absorbs power from antenna radiation. This investigation analyzes the effects of antenna substrate materials on electromagnetic (EM absorption in a human head. Antennas are used in analysis with four different dielectric substrate materials, which are Bakelite, FR4 glass epoxy, Rogers R04003, and Taconic TLC. Moreover, two different thicknesses of each substrate are considered in the experimental setup. The EM absorption associated with two types of cell phone antennas is evaluated in the closed vicinity of the human head model. One of them is planar inverted-F antenna (PIFA, which is used as the internal handset antenna and another one is helical antenna, which is used as external handset antenna. This investigation consists of two different operating frequency bands, GSM 900 MHz and DCS 1800 MHz. The EM absorption in the human head is presented using the peak specific absorption rate (SAR and total absorbed power (TAP by the user. The finite-difference time-domain (FDTD method based on Computer Simulation Technology (CST Microwave studio is utilized in this investigation. The obtained results show that the substrate materials do not effect SAR and TAP values considerably for both antennas, but substrate thickness affects the SAR and TAP values significantly. In addition, the substrate thickness affects the SAR and TAP values significantly in most of the cases Moreover, PIFA produces lower SAR than that of a helical antenna significantly for both GSM and DCS frequency band.DOI: http://dx.doi.org/10.5755/j01.ms.22.3.8889

  9. ZZ SIGMNA-A, Photon Interaction and Absorption Cross-Section Library

    International Nuclear Information System (INIS)

    1 - Description of program or function: - Format: special format; - Number of groups: Photon interaction and absorption coefficients covering the energy range 1 KeV to 100 MeV. - Nuclides: Materials: A150TE PLAST (H, C, N, O, F, Ca); Ac; Air (N, O, Ar); Sb; Ar; As; At; Bakelite (C, H, O); Ba; BARSO4; Be; Bk; Bi; Bone (H, C, N, O, Mg, P, S, Ca); B; Br; C552SHONKA P (H, C, O, F, Si); Cd; Ca; Cf; CAPINTEC (H, C, O, F, Si); C; Ce; Cs; Cl; Cr; Co; Concrete (H, O, Na, Mg, Al, Si, S, K, Ca, Fe); Cu; Cm; Delrin (C, H, O); Dy; Er; Eu; Fat (H, C, N, O, S); F; Fr; FRICK8 (H, O, Na, S, Cl, Fe); Gd; Ga; Ge; Au; Hf; He; Ho; H; ICRP Cortical bone (H, C, N, O, Mg, P, S, Ca, Zn); ICRP Tissue (H, C, N, O, S, Mg, P, S, Cl, K, Ca, Fe, Zn); ICRU Tissue (H, C, N, O); In; I; Ir; Fe; Kr; Pb; LIFTLD (Li, F); Li; Lucite (C, H, O); Lu; Mg; Mn; Hg; Mo; Muscle (H, C, N, O, S, Mg, P, S, K, Ca); Nd; Ne; Np; Ni; Nb; N; Nylon (H, C, N, O); O; Pd; P; Pt; Pu; Po; Polyethylene (C, H); Polystyrene (C, H); K; Pr; Pm; Pa; Ra; Re; Rh; Rb; Ru; Sm; Sc; Se; Si; Ag; Sodium-iodide; Na; SOLWA1; SOLWA2; Sr; S; Ta; Te; Tb; Tl; Th; Tm; Sn; Ti; W; U; V; Water (H, O); Xe; Yb; Y; Zn; Zr. - Origin: Howerton, JRC. An extensive library of photon interaction coefficients has been developed by the Ontario Cancer Institute, Toronto, Ontario, Canada, based on the compilation of Plechaty, Cullen, and Howerton. In addition to partial cross section data, the following are given: mass attenuation coefficients, mass energy transfer coefficients, mass energy absorption coefficients, average energy transferred to electrons, average energy absorbed per interaction, and average stopping power of electrons. Partial interaction coefficients and absorption coefficients are useful in any radiation transport or other radiation analysis application. The data from the Ontario Cancer Institute are given for 94 elements and 25 composite materials covering the energy range 1 KeV to 100 MeV. The reactions considered are coherent and

  10. 利用Q值各向异性识别裂缝走向

    Institute of Scientific and Technical Information of China (English)

    尹志恒; 魏建新; 狄帮让; 李向阳; 孙文博; 齐宇

    2011-01-01

    Using a seismic physical model, we study impact of aligned fractures on Q values of the model, and identify the relationship between fracture orientations and Q value changes. The physical model consists of three layers. The first layer is made of epoxy resin, and the third layer is made of mixed material. Both of them are isotropic layers. The second layer is a bakelite layer, simulating HTI media with aligned vertical fracture. 2D data of three lines from different directions were acquired using the pulse-transmission method with the physical model submerged in a water tank. The pre-stack CDP gathers have been used to calculate Q of target zone by the method QVO (Q versus offset) based on the classical spectral ratio theory. According to the experiment analysis,Q of vertical fractured layer changes versus azimuth, where the biggest of Q value appears in the direction parallel to the fracture orientation and the smallest in the normal direction to the fracture orientation. This would be helpful for the fracture orientation detection.%本文利用地震物理模型方法研究定向排列的裂缝对模型Q值的影响,并找出Q值与地震裂缝走向的关系.物理模型由三层组成,第一层为环氧树脂层,第三层为混合材料,是各向同性介质层;第二层为胶木层,模拟定向排列的垂直裂缝层,是HTI介质层.将物理模型置于水槽中,使用脉冲测量的方法得到物理模拟的三条不同方向测线的二维地面地震数据.对提取的叠前CDP道集数据,使用基于经典的频谱比方法提出的QVO(品质因子Q值随炮检距变化)方法来计算模型目的层位的品质因子.实验结果表明,垂直裂缝层的品质因子Q值随方位角的变化而变化,其中Q最大值方向平行干裂缝走向,最小值方向垂直干裂缝走向,据此可推断裂缝的走向.