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Sample records for duralumin

  1. Pengaruh Temperatur Pada Proses Hot Isostatic Pressing Terhadap Porositas, Keausan Dan Mikrostruktur Sludge Powder Duralumin

    OpenAIRE

    Multazam, Ahmad; Suprapto, Wahyono; Pratikto, Pratikto

    2014-01-01

    Sludge is the starting raw material in the process of forming wheels with forging method. Performance wheels strongly influenced by the quality of sludge. Sludge should have physical properties that light , soft and easy strengthened. One material that can be used as materials for sludge are: duralumin material. Duralumin is another name for aluminum & copper alloy (Al / Cu) with a Cu content of about 4 %. Making sludge powder duralumin with powder metallurgical methods can improve the qu...

  2. Suppression of Fatigue Crack Propagation of Duralumin by Cavitation Peening

    Directory of Open Access Journals (Sweden)

    Hitoshi Soyama

    2015-08-01

    Full Text Available It was demonstrated in the present paper that cavitation peening which is one of the mechanical surface modification technique can suppress fatigue crack propagation in duralumin. The impacts produced when cavitation bubble collapses can be utilised for the mechanical surface modification technique in the same way as laser peening and shot peening, which is called “cavitation peening”. Cavitation peening employing a cavitating jet in water was used to treat the specimen made of duralumin Japanese Industrial Standards JIS A2017-T3. After introducing a notch, fatigue test was conducted by a load-controlled plate bending fatigue tester, which has been originally developed. The fatigue crack propagation behavior was evaluated and the relationship between the fatigue crack propagation rate versus stress intensity factor range was obtained. From the results, the fatigue crack propagation rate was drastically reduced by cavitation peening and the fatigue life of duralumin plate was extended 4.2 times by cavitation peening. In addition, the fatigue crack propagation can be suppressed by 88% in the stable crack propagation stage by cavitation peening.

  3. Taguchi based fuzzy logic optimization of multiple quality characteristics in laser cutting of Duralumin sheet

    Science.gov (United States)

    Pandey, Arun Kumar; Dubey, Avanish Kumar

    2012-03-01

    Capability of laser cutting mainly depends on optical and thermal properties of work material. Highly reflective and thermally conductive Duralumin sheets are difficult-to-laser-cut. Application of Duralumin sheets in aeronautic and automotive industries due to its high strength to weight ratio demand narrow and complex cuts with high geometrical accuracy. The present paper experimentally investigates the laser cutting of Duralumin sheet with the aim to improve geometrical accuracy by simultaneously minimizing the kerf width and kerf deviations at top and bottom sides. A hybrid approach, obtained by combining robust parameter design methodology and Fuzzy logic theory has been applied to compute the fuzzy multi-response performance index. This performance index is further used for multi-objective optimization. The predicted optimum results have been verified by performing the confirmation tests. The confirmation tests show considerable reduction in kerf deviations at top and bottom sides.

  4. An optimal open/closed-loop control method with application to a pre-stressed thin duralumin plate

    Science.gov (United States)

    Nadimpalli, Sruthi Raju

    The excessive vibrations of a pre-stressed duralumin plate, suppressed by a combination of open-loop and closed-loop controls, also known as open/closed-loop control, is studied in this thesis. The two primary steps involved in this process are: Step (I) with an assumption that the closed-loop control law is proportional, obtain the optimal open-loop control by direct minimization of the performance measure consisting of energy at terminal time and a penalty on open-loop control force via calculus of variations. If the performance measure also involves a penalty on closed-loop control effort then a Fourier based method is utilized. Step (II) the energy at terminal time is minimized numerically to obtain optimal values of feedback gains. The optimal closed-loop control gains obtained are used to describe the displacement and the velocity of open-loop, closed-loop and open/closed-loop controlled duralumin plate.

  5. Electrophoretic deposits of boron on duralumin plates used for measuring neutron flux

    International Nuclear Information System (INIS)

    Lang, F.M.; Magnier, P.; Finck, C.

    1956-01-01

    Preparation of boron thin film deposits of around 1 mg per cm 2 on duralumin plates with a diameter of 8 cm. The boron coated plates for ionization chambers were originally prepared at the CEA by pulverization of boron carbides on sodium silicates. This method is not controlling precisely enough the quantity of boron deposit. Thus, an electrophoretic method is considered for a better control of the quantity of boron deposit in the scope of using in the future boron 10 which is costly and rare. The method described by O. Flint is not satisfying enough and a similar electrophoretic process has been developed. Full description of the method is given as well as explanation of the use of dried methanol as solvent, tannin as electrolyte and magnesium chloride to avoid alumina formation. (M.P.)

  6. Electrophoretic deposits of boron on duralumin plates used for measuring neutron flux; Depots electrophoretiques de bore sur plaques de duralumin destines a des mesures de flux de neutrons

    Energy Technology Data Exchange (ETDEWEB)

    Lang, F M; Magnier, P; Finck, C [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

    1956-07-01

    Preparation of boron thin film deposits of around 1 mg per cm{sup 2} on duralumin plates with a diameter of 8 cm. The boron coated plates for ionization chambers were originally prepared at the CEA by pulverization of boron carbides on sodium silicates. This method is not controlling precisely enough the quantity of boron deposit. Thus, an electrophoretic method is considered for a better control of the quantity of boron deposit in the scope of using in the future boron 10 which is costly and rare. The method described by O. Flint is not satisfying enough and a similar electrophoretic process has been developed. Full description of the method is given as well as explanation of the use of dried methanol as solvent, tannin as electrolyte and magnesium chloride to avoid alumina formation. (M.P.)

  7. Investigation of Tribological Properties of Friction Pairs Duralumin – Fluoropolymer Used for Design and Manufacturing of Biomechatronic Devices

    Directory of Open Access Journals (Sweden)

    P. Kovalenko

    2017-06-01

    Full Text Available This paper deals with the processes occurring on the surfaces of materials during the interaction between metal and non-metal parts of various biomechatronic devices, such as prostheses, orthoses and exoskeletons. These mechatronic systems require careful selection of materials for design and manufacturing of their parts taking into consideration not only mechanical properties of the materials, but also their tribological characteristics. Friction pairs duralumin – fluoropolymer and stainless steel 100CrMn6 – fluoropolymer were chosen for the research as the samples. Experimental research was carried out with the use of the universal friction machine MTU-1. For this research, the scheme “plate-on-plate” was used without lubricants. Friction torque, friction coefficient and the temperature in the contact area versus the runtime were obtained as a result of the experiments. Furthermore, estimation of wear of contacting samples was performed. Analysis of the results allowed us to choose suitable materials for design and manufacturing of orthoses, prostheses and exoskeletons.

  8. Analysis of the Surface of Deposited Copper After Electroerosion Treatment

    Science.gov (United States)

    Ablyaz, T. R.; Simonov, M. Yu.; Shlykov, E. S.

    2018-03-01

    An electron microscope analysis of the surface of deposited copper is performed after a profiling-piercing electroerosion treatment. The deposited copper is treated with steel, duralumin, and copper electrode tools at different pulse energies. The treatment with the duralumin electrode produces on the treated surface a web-like structure and cubic-morphology polyhedral dimples about 10 μm in size. The main components of the surface treated with the steel electrode are developed polyhedral dimples with a size of 10 - 50 μm. After the treatment with the copper electrode the main components of the treated surface are large polyhedral dimples about 30 - 80 μm in size.

  9. Untitled

    Indian Academy of Sciences (India)

    tation occurs in several aluminium alloys of commercial importance. The forma- tion of CuAl2 precipitates in duralumin, an alloy of Al with about 4' 5% copper, is an example: matrix (a) - depleted matrix (a) -- CuAl (O). 4.5% Cu. 0.5% Cu. 52%. Cu. Figure 4. Austenite of 0.8% carbon transforms to alternate lamellae of ferrite.

  10. Surface mechanics design by cavitation peening

    OpenAIRE

    Hitoshi Soyama

    2015-01-01

    Although impacts at cavitation bubble collapses cause severe damage in hydraulic machineries, the cavitation impacts can be utilised for surface mechanics design such as introduction of compressive residual stress and/or improvement of fatigue strength. The peening method using the cavitation impacts was called as cavitation peening. In order to reveal the peening intensity of hydrodynamic cavitation and laser cavitation, the arc height of Almen strip and duralumin plate were measured. In the...

  11. Research on a new type of precision cropping method with variable frequency vibration

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    Aiming at the cropping operations widely applied in practical industry production, a new method of bar cropping is presented. The rotational speeds of actuating motor of eccentric blocks are controlled by a frequency-changer, and the shearing die provides the bar with the controllable force, frequency and amplitude of vibration. By utilizing the stress concentration at the bottom of V shape groove on the bar, the low stress bar cropping is realized. The bar cropping experiments of duralumin alloy and steel ...

  12. Construction of dry-boxes for plutonium metallurgy; Construction des boites a gants pour la metallurgie du plutonium

    Energy Technology Data Exchange (ETDEWEB)

    Grison, E; Pascard, R [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

    1958-07-01

    The dry-boxes used at Chatillon are of two main types: a) boxes with a metal frame work of welded angle-pieces, panels of plexiglass, bakelite, duralumin, etc... They include a standard panel which enables them to be connected up to the contaminated repairs workshop; b) boxes made entirely of welded plastic. The working face only is of plexiglas held by screw clamps to a pure rubber joint. These boxes, which cannot be connected to the contaminated workshop, are generally reserved for small pieces of chemical apparatus. None has yet been used for working under argon, although their airtightness is excellent. After an interval of several hours, in fact, no decrease in the pressure inside the box can be detected. Several means can be adopted to ensure that the joints between panels and mountings are absolutely air-tight. Up to the present we are using three types of box with metal framework at the same time, without being able to make a definitive choice. (author) [French] Les boites a gants utilisees a Chatillon sont de deux types principaux: a) boites a armature metallique en cornieres soudees, panneaux en plexiglas, bakelite, duralumin, etc... Elles comportent un panneau standard permettant de les raccorder a l'atelier de reparations contamine; b) boites entierement en matiere plastique soudee. Seule la face de travail est en plexiglas appliquee par serre-joints sur un joint de caoutchouc pur. Ces boites, qui ne peuvent etre raccordees a l'atelier contamine, sont en general reservees a du petit materiel de chimie. Aucune, jusqu'a present, n'a ete utilisee pour le travail sous argon bien que leur etancheite soit excellente. On ne detecte en effet sur un intervalle de plusieurs heures aucune diminution de la depression regnant dans la boite. Plusieurs solutions peuvent etre adoptees pour assurer l'etancheite des panneaux sur les montants. Jusqu'a ce jour, nous utilisons concurremment trois types de boites a armature metallique sans qu'il soit possible de faire un

  13. Magnetically suspended experimental vehicle-strength of structure and dynamic analysis

    Energy Technology Data Exchange (ETDEWEB)

    Nagahiro, T; Terada, K; Kasai, Y; Motonaga, M

    1973-06-01

    To cope with rapid increase in demand for railroad transportation, studies in magnetically suspended high speed trains are being pushed forward at the Japanese National Railways. Recently a special experimental vehiclc was completed which will be used by JNR in experiments concerning magnetic propulsion and suspension of magnetically suspended high speed trains. This test vehicle is provided with reaction plates of linear induction motor under the floor at about the center of the vehicle, with superconducting magnets for suspension on both sides. The vehicle body is made mainly of high tensile strengthened aluminium (duralumin) for weight reduction, but its strength was checked by the vibration analysis and load tests carried out in the suspended condition. Remote-operated from the control tower, this unmanned test vehicle will provide a key to the completion of a super-high speed magnetically suspended train.

  14. Construction of dry-boxes for plutonium metallurgy

    International Nuclear Information System (INIS)

    Grison, E.; Pascard, R.

    1958-01-01

    The dry-boxes used at Chatillon are of two main types: a) boxes with a metal frame work of welded angle-pieces, panels of plexiglass, bakelite, duralumin, etc... They include a standard panel which enables them to be connected up to the contaminated repairs workshop; b) boxes made entirely of welded plastic. The working face only is of plexiglas held by screw clamps to a pure rubber joint. These boxes, which cannot be connected to the contaminated workshop, are generally reserved for small pieces of chemical apparatus. None has yet been used for working under argon, although their airtightness is excellent. After an interval of several hours, in fact, no decrease in the pressure inside the box can be detected. Several means can be adopted to ensure that the joints between panels and mountings are absolutely air-tight. Up to the present we are using three types of box with metal framework at the same time, without being able to make a definitive choice. (author) [fr

  15. Development of a portable power system with meso-scale vortex combustor and thermo-electric device

    International Nuclear Information System (INIS)

    Shimokuri, D; Hara, T; Ishizuka, S

    2014-01-01

    In this study, a small scale power generation system with a meso-scale vortex combustor has been developed. The system was consisted of a couple of thermo-electric device and a heat medium. The medium was made of duralumin, 40 × 40 × 20 mm and 52 g weight, and the vortex combustion chamber of 7 mm inner diameter was embedded in it. It was found that a stable flame could be established in the narrow 7 mm channel even the mean axial velocity reached 1.2 m/s. And furthermore, the vortex flow significantly enhanced the heat transfer from the burned gas to combustion chamber, and as a result, the medium was heated to 300°C quickly (within 5 minutes) by the combustion of propane / air mixture for 145W input energy. The system could successfully generate 1.98 W (4.3 V and 0.46 A), which corresponded to the energy conversion rate of 0.7 % per unit thermo-electric device

  16. Evaluation of aerodynamic forces acting on oscillating cantilever beams based on the study of the damped flexural vibration of aluminium test samples

    Science.gov (United States)

    Egorov, A. G.; Kamalutdinov, A. M.; Nuriev, A. N.

    2018-05-01

    The paper is devoted to study of the aerodynamic forces acting on flat cantilever beams performing flexural vibrations in a viscous fluid. Original method for the force evaluation is presented based on analysis of experimental measurements of a logarithmic decrement of vibrations and relative variation in frequency of duralumin test specimens. The theoretical core of the method is based on the classical theory of bending beam oscillations and quasi-two dimensional model of interaction between a beam and a gas. Using the proposed method, extensive series of experiments for a wide range of oscillations parameters were carried out. The processing of the experimental data allowed to establish the global influence of the aerodynamic effects on beam oscillations and the local force characteristics of each cross-section of the beam in the form of universal functions of dimensionless amplitude and dimensionless frequency of oscillation. The obtained estimates of the drag and added mass forces showed a good correspondence with the available numerical and experimental data practically in the entire range of the investigated parameters.

  17. Photothermal radiometry applied to characterization and control of thermal contact resistance of crimped metals; Radiometrie photothermique appliquee a la caracterisation et au controle de la resistance thermique de contact de metaux sertis

    Energy Technology Data Exchange (ETDEWEB)

    Van Schel, Etienne

    1989-11-15

    Modulated photothermal radiometry is used to study the thermal contact between two metals. At first, two models using a bidimensional axisymmetric geometry are proposed to describe the interface: the first one deals with thermal contact resistance, the second one with an equivalent layer. A thorough calculation of the photothermal signal taking into account the nature of the sample and the detection is here presented. Theoretical simulations show the influence of several parameters (frequency. dimensions of the excitation and the detection) on the sensitivity of the method applied to the detection of the thermal resistance. The comparison, with a three layer-model justifies the use of thermal resistance in periodical regime, for air layers between metals. Then, we present an experimental device that is used to validate the model. The results, obtained on duralumin-copper samples, show the sensitivity of the method and lead us to propose values of thermal contact resistance for different crimpings. At last an industrial testing equipment is described. The results, obtained on laboratory samples, are confirmed. Heat exchanger pipes, including voluntary defects are tested. Thanks to this device, we are able to make an in situ crimping control that can also be applied to other types of contacts. [French] La radiometrie photothermique est utilisee pour etudier le contact thermique entre deux metaux. Tout d'abord, deux modeles utilisant une geometrie bidimensionnelle axisymetrique sont proposes pour decrire l'interface: le premier utilise une resistance thermique de contact, le second un milieu equivalent Un calcul complet du signal photothermique, prenant en compte la nature de l'echantillon et de la detection, est presente. Des simulations theoriques montrent l'influence de quelques parametres (frequence, dimensions de l'excitation et de la detection) sur la sensibilite de la methode a la detection de la resistance thermique. La comparaison, avec un modele a trois

  18. Strength tests of thin-walled elliptic duralumin cylinders in pure bending and in combined pure bending and torsion

    Science.gov (United States)

    Lundquist, Eugene E; Stowell, Elbridge Z

    1942-01-01

    An analysis is presented of the results of tests made by the Massachusetts Institute of Technology and by the National Advisory Committee for Aeronautics on an investigation of the strength of thin-walled circular and elliptic cylinders in pure bending and in combined torsion and bending. In each of the loading conditions, the bending moments were applied in the plane of the major axis of the ellipse.

  19. Surface mechanics design by cavitation peening

    Directory of Open Access Journals (Sweden)

    Hitoshi Soyama

    2015-07-01

    Full Text Available Although impacts at cavitation bubble collapses cause severe damage in hydraulic machineries, the cavitation impacts can be utilised for surface mechanics design such as introduction of compressive residual stress and/or improvement of fatigue strength. The peening method using the cavitation impacts was called as cavitation peening. In order to reveal the peening intensity of hydrodynamic cavitation and laser cavitation, the arc height of Almen strip and duralumin plate were measured. In the case of hydrodynamic cavitation, cavitation was generated by injecting a high speed water jet into water with a pressurised chamber and an open chamber, and the cavitating jet in air was also examined. The laser cavitation was produced by a pulse laser, and a high speed observation using a high speed video camera was carried out to clarify laser abrasion and laser cavitation with detecting noise by a hydrophone. It was concluded that the peening intensity by using the cavitating jet in water with the pressurized chamber was most aggressive, and the impact induced by the laser cavitation was larger than that of the laser abrasion at the present condition.

  20. Corrosion resistant materials for fluorine and hydrogen fluoride

    International Nuclear Information System (INIS)

    Hauffe, K.

    1984-01-01

    Aluminum and Duralumin are resistant against fluorine and hydrogen fluoride up to 600 and 700 K, respectively. The resistance of nickel and its alloys, particularly monel, against fluorine and hydrogen fluoride is fairly good up to 900 and 800 K. During the attack of nickel-chromium alloys by fluorine between 1000 and 1300 K, it appears an inner fluorination similarly to the inner oxidation. The resistance of titanium in water-free liquid fluorine at lower temperatures with -1 is comparable to that of nickel and monel. However, the corrosion of titanium in gaseous fluorine amounts at 377 K only 0,0082 mm.a -1 . In spite of their limited resistance against fluorine and hydrogen fluoride, very pure molybdenum and tungsten are employed as construction materials in the rocket technology because of their large strength at high temperatures if fluorine-hydrogen and fluorine-hydrazine flames are used. Lanthanum and calcium borides are only little attacked by fluorine hydrazine flames between 1400 and 1800 K; they are superior to all special grade alloys. The same is true in a lower temperature region (290-400 K) with fluorcarbon resins. Organic materials substitute in increasing extent metal alloys and non-metal inorganic materials. (orig.) [de

  1. Corrosion resistant materials for fluorine and hydrogen fluoride

    Energy Technology Data Exchange (ETDEWEB)

    Hauffe, K.

    1984-12-01

    Aluminum and Duralumin are resistant against fluorine and hydrogen fluoride up to 600 and 700 K, respectively. The resistance of nickel and its alloys, particularly monel, against fluorine and hydrogen fluoride is fairly good up to 900 and 800 K. During the attack of nickel-chromium alloys by fluorine between 1000 and 1300 K, it appears an inner fluorination similarly to the inner oxidation. The resistance of titanium in water-free liquid fluorine at lower temperatures with <0,3 mm.a/sup -1/ is comparable to that of nickel and monel. However, the corrosion of titanium in gaseous fluorine amounts at 377 K only 0,0082 mm.a/sup -1/. In spite of their limited resistance against fluorine and hydrogen fluoride, very pure molybdenum and tungsten are employed as construction materials in the rocket technology because of their large strength at high temperatures if fluorine-hydrogen and fluorine-hydrazine flames are used. Lanthanum and calcium borides are only little attacked by fluorine hydrazine flames between 1400 and 1800 K; they are superior to all special grade alloys. The same is true in a lower temperature region (290-400 K) with fluorcarbon resins. Organic materials substitute in increasing extent metal alloys and non-metal inorganic materials.

  2. A T-shape linear piezoelectric motor with single foot.

    Science.gov (United States)

    Liu, Yingxiang; Chen, Weishan; Yang, Xiaohui; Liu, Junkao

    2015-02-01

    A new T-shape piezoelectric motor using the hybrid of two orthogonal longitudinal vibrations is proposed in this work. Six pieces of PZT ceramic plates are bonded on the upside and downside surfaces of a T-shape duralumin alloy base respectively to form the proposed motor. Elliptical movement can be generated on the driving tip by applying sine and cosine voltages to the PZT elements. The horizontal displacement of the driving tip will push the runner while the vertical displacement can overcome the preload. Finite element method is used to accomplish the design and analysis process. The resonance frequencies of the two vibration modes are tuned to be close by modal analysis, while the motion trajectory of the driving tip is observed by transient analysis. After the fabrication of a prototype, the vibration characteristics and mechanical output ability are measured. The no-load speed and the maximum output thrust force of the proposed motor are tested to be 718 mm/s and 3.5 N under an exciting frequency of 53.1 kHz. The proposed T-shape piezoelectric motor exhibits merits of simple structure, easy to realize miniaturization, easy to be fabricated, and high power-to-weight ratio. Copyright © 2014 Elsevier B.V. All rights reserved.

  3. A Motor/Generator for Flywheel Energy Storage System Levitated by Bulk Superconductor

    Energy Technology Data Exchange (ETDEWEB)

    Koh, C.S.; Yeon, J.U.; Jeoung, H.M.; Choi, J.H. [Chungbuk National University (Korea); Lee, H.J; Hong, G.W. [Korea Atomic Energy Research Institute (Korea)

    2000-06-01

    The energy storage systems are being widely researched for the high quality of the electric power. The FES(flywheel energy storage system)is especially, on the center of the research because it does not make any pollution and its life is long. The FES converts the electrical energy into the mechanical kinetic energy of the flywheel and reconverts the mechanical energy into the electrical energy, In order to store as much energy as possible, the flywheel is supposed to be rotated with very high speed. The motor/generator of the FES should be high efficient at high speed, and generate constant torque with respect to the rotation. In this paper, a motor/generator employing a Halbach array of permanent magnets is designed and constructed to meet the requirements, and its characteristics are examined. The magnetic field is analysed by using the magnetic surface charge method. The armature winding is designed for the harmonic components to be minimized by using the FFT. The sinusoidal currents for the motor driving are generated by the hysteresis current controller. A sample superconducting flywheel energy storage system is constructed with a duralumin flywheel which has a maximum rotating speed of 40,000[rpm] and a stored energy of 240[Wh] and its validity is examined through the experiment. (author). 15 refs., 17 figs., 2 tabs.

  4. PCBs determination in water, soils and biota by perchlorination and GC-ECD

    Energy Technology Data Exchange (ETDEWEB)

    Feshin, D. [Institute of Ecology and Evolution RAS, Moscow (Russian Federation); Klyuev, N.; Brodsky, E.; Kalinkevich, G.

    2004-09-15

    Most of the PCB pollutions are caused by industrial application. PCB-containing mixtures whose compositions are well known and constant should be rapidly and precisely analyzable as total PCB to monitor real pollution exposure. Consequently, a simple but reproducible and cheap method for operative control is needed which should be periodically controlled by standard analytical methods. So it is advisable to have a rapid method that will allow PCBs determination in wide range of quantities by simple instrumentation with internal standards. The method based on perchlorination of PCBs considerably simplifies the detection of PCB congeners as compared to other techniques. In this practice all polychlorinated derivatives are converted into decachlorobiphenyl (DCB). This is followed by gas chromatography with electron capture detector (GC-ECD), which is highly sensitive for the substances of interest. Currently EPA procedure 508a (1989) is the only official screening method for detection of PCBs using perchlorination. This uses SbCl5 and powdered Fe mixture as reagent at 270 C without internal standard. We reported about using of perchlorination reagent based on mixture of powdered duralumin, sulphur and SO2Cl2 heated at 105 C for 2 h for detection of PCBs as decachlorobiphenyls in a wide range of concentration: 16.4 ng/sample to 164 {mu}/sample. 4,4'-difluorobiphenyl was proposed as internal standard that allowed to control all steps of sample preparation including perchlorination reaction. In the present work we extended our experience of perchlorination to detect the PCBs.

  5. Discharge source coupled to a deceleration unit for anion beam generation: Application to H{sub 2}{sup −} photodetachment

    Energy Technology Data Exchange (ETDEWEB)

    Rudnev, V.; Ureña, A. González [Unidad de Láseres y Haces Moleculares, Instituto Pluridisciplinar, Universidad Complutense, Juan XXIII-1, Madrid 28040 (Spain)

    2013-12-15

    A cathode discharge source coupled to a deceleration unit for anion beam generation is described. The discharge source, made of stainless steel or duralumin electrodes and Macor insulators, is attached to the exit nozzle valve plate at one end, and to an Einzel lens to the other end. Subsequently, a cylindrical retardation unit is attached to the Einzel lens to decelerate the ions in order to optimize the laser beam interaction time required for spectroscopic investigations. The compact device is able to produce beam intensities of the order of 2 × 10{sup 12} anions/cm{sup 2} s and 20 μrad of angular divergence with kinetic energies ranging from 30 to 120 eV. Using distinct gas mixtures for the supersonic expansion together with a linear time-of-flight spectrometer, anions of great relevance in molecular astrophysics like, for example, H{sub 2}{sup −}, C{sub 3}H{sup −}, C{sub 2}{sup −}, C{sub 2}H{sup −}, HCN{sub 2}{sup −}, CO{sub 2}{sup −}, CO{sub 2}H{sup −}, C{sub 4}{sup −}, C{sub 4}H{sup −}, C{sub 5}H{sub 4}{sup −}, C{sub 5}H{sub 6}{sup −}, C{sub 7}N{sup −}, and C{sub 10}N{sup −} were produced. Finally, in order to demonstrate the capability of the experimental technique the photodetachment cross-section of the metastable H{sub 2}{sup −}, predominantly in the (v = 0, J = 26) state, was measured following laser excitation at λ{sub exc}= 565 nm obtaining a value of σ{sub ph}= 0.04 Å. To the best of our knowledge, it is the first time that this anion cross-section has been measured.

  6. Q-switched Nd:YAG/V:YAG microchip 1338 nm laser for laser-induced breakdown spectroscopy

    Science.gov (United States)

    Šulc, Jan; Jelínková, Helena; Nejezchleb, Karel; Škoda, Václav

    2017-12-01

    Q-switched microchip laser emitting radiation at wavelength 1338nm was tested as a radiation source for laser induced breakdown spectroscopy (LIBS). This laser used sandwich crystal which combined in one piece the cooling part (undoped YAG crystal 4mm long), the active laser part (Nd:YAG crystal 12mm long), and the saturable absorber (V:YAG crystal 0.7mm long). The diameter of this crystal was 5 mm. The microchip resonator consisted of dielectric mirrors directly deposited on the monolith crystal surfaces. The pump mirror (HT @ 808 nm, HR @ 1.3 ¹m) was placed on the undoped YAG part. The output coupler (R = 90% @ 1338 nm) was placed on the V:YAG part. The fibre-coupled 808nm pumping laser diode was operating in pulsed regime (rep. rate 250 Hz, pulse width 300 ¹s, pulse energy 6 mJ). Using this pumping, stable and high reproducible Q-switched pulses were generated at wavelength 1338 nm. Pulse length was 6.2 ns (FWHM) and the mean output power was 33mW. The single pulse energy and peak power was 0.13mJ and 21kW, respectively. Laser was operating in fundamental TEM00 mode. The laser radiation was focused on a tested sample using single plano-convex lens (focal length 75 mm). The focal spot radius was 40 ¹m. The corresponding peak-power density was 0.83GW/cm2. The laser induced break-down was successfully reached and corresponding laser-induced plasma spectra were recorded for set of metallic elements (Cu, Ag, Au, In, Zn, Al, Fe, Ni, Cr) and alloys (Sn-Pb solder, duralumin, stainless-steel, brass). To record the spectra, StellarNet BLACK-Comet concave grating CCD-based spectrometer was used without any special collimation optics. Thanks to used laser wavelength far from the detector sensitivity, no special filtering was needed to overcome the CCD dazzling. The constructed laser could significantly improve repletion-rate of up-to-date LIBS devices.

  7. Uso de fijador externo en la inestabilidad de la pared torácica anterior (volet esternal: Presentación de un caso Use of the external fixative in the instability of the anterior thoraxic wall (sternal volet: A case report

    Directory of Open Access Journals (Sweden)

    Orestes N Mederos Curbelo

    2005-03-01

    external stabilization was attained by an equipment that is utilized in our hospital and that is reusable and may be applied to any thoracic instability independently of its localization. The fixative is made of malleable duralumin plates that make possible its adaptability and introduce a way of treatment in the bilateral thoracic lesions with external instability, a complex situation in which it may be a useful instrument for treatment

  8. Fabrication of advanced military radiation detector sensor and performance evaluation

    International Nuclear Information System (INIS)

    Kang, Sin Yang

    2010-02-01

    shows a performance comparable to commercial ones. The beta ray sensor was manufactured using a BC-408 organic plastic scintillator. The main goal of this study was the measurement of beta - ray responses of the PMMA light guide attached to the sensor and the determination of window materials. Finally, the CsI(Tl) scintillator gamma ray sensor manufactured as engineering model and the shielding case was made of duralumin (side plane) and aluminium (window). The performance of the gamma - ray sensor was comparable to commercial high - sensitivity industrial sensors. These three types of scintillation sensors can be used directly as military equipment. And this study helps improving the protection of our country from nuclear threats

  9. Fabrication of advanced military radiation detector sensor and performance evaluation

    Energy Technology Data Exchange (ETDEWEB)

    Kang, Sin Yang

    2010-02-15

    efficiency: 41%). This alpha - particle sensor shows a performance comparable to commercial ones. The beta ray sensor was manufactured using a BC-408 organic plastic scintillator. The main goal of this study was the measurement of beta - ray responses of the PMMA light guide attached to the sensor and the determination of window materials. Finally, the CsI(Tl) scintillator gamma ray sensor manufactured as engineering model and the shielding case was made of duralumin (side plane) and aluminium (window). The performance of the gamma - ray sensor was comparable to commercial high - sensitivity industrial sensors. These three types of scintillation sensors can be used directly as military equipment. And this study helps improving the protection of our country from nuclear threats

  10. Elastic Nonlinear Response in Granular Media Under Resonance Conditions

    Science.gov (United States)

    Jia, X.; Johnson, P. A.

    2004-12-01

    We are studying the elastic linear and nonlinear behavior of granular media using dynamic wave methods. In the work presented here, our goal is to quantify the elastic nonlinear response by applying wave resonance. Resonance studies are desirable because they provide the means to easily study amplitude dependencies of elastic nonlinear behavior and thus to characterize the physical nature of the elastic nonlinearity. This work has implications for a variety of topics, in particular, the in situ nonlinear response of surface sediments. For this work we constructed an experimental cell in which high sensitivity dynamic resonance studies were conducted using granular media under controlled effective pressure. We limit our studies here to bulk modes but have the capability to employ shear waves as well. The granular media are composed of glass beads held under pressure by a piston, while applying resonance waves from transducers as both the excitation and the material probe. The container is closed with two fitted pistons and a normal load is applied to the granular sample across the top piston. Force and displacement are measured directly. Resonant frequency sweeps with frequencies corresponding to the fundamental bulk mode are applied to the longitudinal source transducer. The pore pressure in the system is 1 atm. The glass beads used in our experiments are of diameter 0.5 mm, randomly deposited in a duralumin cylinder of diameter 30 mm and height of 15 mm. This corresponds to a granular skeleton acoustic wave velocity of v ª 750m/s under 50 N of force [0.07 Mpa]. The loaded system gives fundamental mode resonances in the audio frequency band at half a wavelength where resonance frequency is effective-pressure dependent. The volume fraction of glass beads thus obtained is found to be 0.63 ± 0.01. Plane-wave generating and detecting transducers of diameter 30 mm are placed on axis at the top and bottom of the cylindrical container in direct contact with the glass