WorldWideScience

Sample records for rotating-substrate pvd systems

  1. Corrosion behaviour of Arc-PVD coatings and hybrid systems

    International Nuclear Information System (INIS)

    Reichel, K.

    1992-01-01

    To achieve a comprehensive protective effect against corrosion and wear stresses, coating systems are increasingly being developed, in which there is a separation of the tasks of the coating materials regarding the protective effect. On the one hand, pure PVD coating systems are used, on the other hand hybrid coatings are examined, where galvanic processes are combined with PVD technique. The results of experiments introduced in this article were determined on Arc-PVD coatings. By this process, titanium nitride and chromium nitride coatings are both deposited directly on the basic material and are also deposited as combination coatings of Ti/TiN and chemical nickel/TiN. (orig.) [de

  2. Development of Production PVD-AIN Buffer Layer System and Processes to Reduce Epitaxy Costs and Increase LED Efficiency

    Energy Technology Data Exchange (ETDEWEB)

    Cerio, Frank

    2013-09-14

    was analyzed and improvements implemented to the Veeco PVD-AlN prototype system to establish a specification and baseline PVD-AlN films on sapphire and in parallel the evaluation of PVD AlN on silicon substrates began. In Phase II of the project a Beta tool based on a scaled-up process module capable of depositing uniform films on batches of 4”or 6” diameter substrates in a production worthy operation was developed and qualified. In Phase III, the means to increase the throughput of the PVD-AlN system was evaluated and focused primarily on minimizing the impact of the substrate heating and cooling times that dominated the overall cycle time.

  3. Relation of Thermal Conductivity with Process Induced Anisotropic Void Systems in EB-PVD PYSZ Thermal Barrier Coatings

    Energy Technology Data Exchange (ETDEWEB)

    Renteria, A. Flores; Saruhan-Brings, B.; Ilavsky, J.

    2008-03-03

    Thermal barrier coatings (TBCs) deposited by Electron-beam physical deposition (EB-PVD) protect the turbine blades situated at the high pressure sector of the aircraft and stationary turbines. It is an important task to uphold low thermal conductivity in TBCs during long-term service at elevated temperatures. One of the most promising methods to fulfil this task is to optimize the properties of PYSZ-based TBC by tailoring its microstructure. Thermal conductivity of the EB-PVD produced PYSZ TBCs is influenced mainly by the size, shape, orientation and volume of the various types of porosity present in the coatings. These pores can be classified as open (inter-columnar and between feather arms gaps) and closed (intra-columnar pores). Since such pores are located within the three-dimensionally deposited columns and enclose large differences in their sizes, shapes, distribution and anisotropy, the accessibility for their characterization is very complex and requires the use of sophisticated methods. In this work, three different EB-PVD TBC microstructures were manufactured by varying the process parameters, yielding various characteristics of their pores. The corresponding thermal conductivities in as-coated state and after ageing at 11000C/1h and 100h were measured via Laser Flash Analysis Method (LFA). The pore characteristics and their individual effect on the thermal conductivity are analysed by USAXS which is supported by subsequent modelling and LFA methods, respectively. Evident differences in the thermal conductivity values of each microstructure were found in as-coated and aged conditions. In summary, broader columns introduce higher values in thermal conductivity. In general, thermal conductivity increases after ageing for all three investigated microstructures, although those with initial smaller pore surface area show smaller changes.

  4. Relation of thermal conductivity with process induced anisotropic void system in EB-PVD PYSZ thermal barrier coatings.

    Energy Technology Data Exchange (ETDEWEB)

    Renteria, A. F.; Saruhan, B.; Ilavsky, J.; German Aerospace Center

    2007-01-01

    Thermal barrier coatings (TBCs) deposited by Electron-beam physical deposition (EB-PVD) protect the turbine blades situated at the high pressure sector of the aircraft and stationary turbines. It is an important task to uphold low thermal conductivity in TBCs during long-term service at elevated temperatures. One of the most promising methods to fulfil this task is to optimize the properties of PYSZ-based ,TBC by tailoring its microstructure. Thermal conductivity of the EB-PVD produced PYSZ TBCs is influenced mainly by the size, shape, orientation and volume of the various types of porosity present in the coatings. These pores can be classified as open (inter-columnar and between feather arms gaps) and closed (intra-columnar pores). Since such pores are located within the three-dimensionally deposited columns and enclose large differences in their sizes, shapes, distribution and anisotropy, the accessibility for their characterization is very complex and requires the use of sophisticated methods. In this work, three different EB-PVD TBC microstructures were manufactured by varying the process parameters, yielding various characteristics of their pores. The corresponding thermal conductivities in as-coated state and after ageing at 1100C/1h and 100h were measured via Laser Flash Analysis Method (LFA). The pore characteristics and their individual effect on the thermal conductivity are analysed by USAXS which is supported by subsequent modelling and LFA methods, respectively. Evident differences in the thermal conductivity values of each microstructure were found in as-coated and aged conditions. In summary, broader columns introduce higher values in thermal conductivity. In general, thermal conductivity increases after ageing for all three investigated microstructures, although those with initial smaller pore surface area show smaller changes.

  5. Morphology of PVD films

    International Nuclear Information System (INIS)

    Carr, M.J.; Grotzky, V.K.; Helms, C.J.; Johns, W.L.; Naimon, E.R.; Rafalski, A.L.; Smith, C.J.

    1982-01-01

    Experimental data show that the morphology of PVD chromium coatings is dependent on substrate temperature, deposition rate, and the oxygen content of the chromium source material. For chromium containing about 700-ppM oxygen, a variety of morphologies can form depending on substrate temperature and deposition rate. For chromium contaning 1000 to 2000 ppM of oxygen, porous coatings of the Type IV variety are produced over essentially the full range of temperatures and rates possible with current coating equipment. For chromium containing less than about 400 ppM of oxygen, dense coatings of the Type I variety are produced over the range of temperatures and rates investigated

  6. High temperature oxidation behavior of hafnium modified NiAl bond coat in EB-PVD thermal barrier coating system

    Energy Technology Data Exchange (ETDEWEB)

    Guo Hongbo; Sun Lidong; Li Hefei [Department of Material Science and Engineering, Beijing University of Aeronautics and Astronautics, No.37 Xueyuan Road, Beijing 100083 (China); Gong Shengkai [Department of Material Science and Engineering, Beijing University of Aeronautics and Astronautics, No.37 Xueyuan Road, Beijing 100083 (China)], E-mail: gongsk@buaa.edu.cn

    2008-06-30

    NiAl coatings doped with 0.5 at.% and 1.5 at.% Hf were produced by co-evaporation of NiAl and Hf ingots by electron beam physical vapor deposition (EB-PVD), respectively. The addition of 0.5 at.% Hf significantly improved the cyclic oxidation resistance of the NiAl coating. The TGO layer in the 1.5 at.% Hf doped NiAl coating is straight; while that in the 0.5 at.% Hf doped coating became undulated after thermal cycling. The doped NiAl thermal barrier coatings (TBCs) revealed improved thermal cycling lifetimes at 1423 K, compared to the undoped TBC. Failure of the 0.5 at.% Hf doped TBC occurred by cracking at the interface between YSZ topcoat and bond coat, while the 1.5 at.% Hf doped TBC cracked at the interface between bond coat and substrate.

  7. Lifetime-determining spalling mechanisms of NiCoCrAlRe/EB-PVD zirconia TBC systems

    Energy Technology Data Exchange (ETDEWEB)

    Fritscher, K.; Schulz, U. [DLR - German Aerospace Center, Institute of Materials Research, 51170 Cologne (Germany); Leyens, C. [Technical University of Brandenburg (BTU) Cottbus, Chair of Physical Metallurgy and Materials Technology, 03046 Cottbus (Germany)

    2007-09-15

    The mechanisms that control the lifetime of thermal barrier coating (TBC) systems have been traced by two particular overlay bondcoats serving as model systems: superalloy pins (IN100, CMSX-4) with two alternative NiCoCrAlRE (RE: Hf, Y) bond coat compositions (i) NiCoCrAlY without and (ii) with co-dopants of silicon and hafnium. On top an electron-beam physical-vapor deposited (EB-PVD) yttria partially stabilized zirconia (YPSZ) TBC commonly mixed with 2 wt.% hafnia, or, rarely with 10 wt.%, was applied. The test pins were thermo-cycled at 1100 and 1150 C until failure. Identical lifetimes in cyclic tests on YPSZ TBCs with 2 (relatively high sintering rate) and 10 wt.% hafnia (relatively low sintering rate) preclude an effect of diffusion mechanisms of the YPSZ TBC on lifetime. The fit of lifetimes and test temperatures to Arrhenius-type relationships gives activation energies for failure. These energies agree with the activation energies for anion and cation diffusion in alumina for the respective bondcoat variant: (i) for the NiCoCrAlY/TBC system for O{sup 2-} diffusion in alumina, (ii) for the NiCoCrAlYSiHf/TBC system for Al{sup 3+} diffusion in alumina. SEM and EDS investigations of the thermally grown oxides (TGOs) confirm the mechanisms responsible for TBC failure as indicated by activation energies. Two categories of failure can be distinguished: (i) NiCoCrAlY coatings fail by an ''adhesive mode of failure'' along smooth bond coat/TGO interfaces driven by a critical TGO thickness. (ii) NiCoCrAlYSiHf coatings fail later and more reluctantly by a ''cohesive'' crack mode via de-cohesion at the TGO/TBC interface. In the latter case a quasi-integrity of the crack-affected TGO is lengthily maintained up to failure by a crack-pinning mechanism which runs via Al{sup 3+} supply from the bondcoat. (Abstract Copyright [2007], Wiley Periodicals, Inc.) [German] Die Mechanismen, welche die Lebensdauer von Waermedaemmschichtsystemen

  8. The Study of Deposition Parameters, Properties for PVD TixN and CrxN Coatings Using a Closed Field Unbalanced Magnetron Sputter Ion Plating System

    Institute of Scientific and Technical Information of China (English)

    Hailin Sun; Susan Field; Jian Chen; Dennis. G. Teer

    2004-01-01

    Closed Field Unbalanced Magnetron Sputter Ion Plating (CFUBMSIP) systems have been used increasingly for PVD coating in recent years. TiN and CrN coatings, commonly used as the basic coating for a number of different hard coatings, have been chosen to study the coating process parameters for the CFUBMSIP system. In this paper, the process parameters, such as substrate temperature, substrate bias and OEM control, have been carefully examined to achieve hard and wear-resistance coatings with good adhesion. The coating structure and orientation were found to change according to the coating parameters. The Rockwell test and Scratch test were carried out to examine the coating adhesion; pin-on-disc testing was used to estimate the wear-resistant; micro-hardness was also used to determine coating hardness. HSS drill testing has been carried out to study the general properties of the coating for cutting tool application. A combination of process parameters can be selected to achieve good performance for the TiN and CrN coatings.

  9. High speed PVD thermal barrier coatings

    Energy Technology Data Exchange (ETDEWEB)

    Beele, W. [Sulzer Metco Coatings BV (Netherlands); Eschendorff, G. [Sulzer Metco Coatings BV (Netherlands); Eldim BV (Netherlands)

    2006-07-15

    The high speed PVD process (HS-PVD) combines gas phase coating synthesis with high deposition rates. The process has been demonstrated for high purity YSZ deposited as a chemically bonded top thermal barrier with columnar structure of EB-PVD features. The process can manufacture EB-PVD like coatings that match in regards to their TGO-formation and columnar structure. Coatings with a columnar structure formed by individual columns of 1/4 of the diameter of a classical EB-PVD type TBC have been deposited. These coatings have the potential to prove a significant reduction in thermal conductivity and in erosion performance. (Abstract Copyright [2006], Wiley Periodicals, Inc.)

  10. High speed PVD thermal barrier coatings

    International Nuclear Information System (INIS)

    Beele, W.; Eschendorff, G.

    2006-01-01

    The high speed PVD process (HS-PVD) combines gas phase coating synthesis with high deposition rates. The process has been demonstrated for high purity YSZ deposited as a chemically bonded top thermal barrier with columnar structure of EB-PVD features. The process can manufacture EB-PVD like coatings that match in regards to their TGO-formation and columnar structure. Coatings with a columnar structure formed by individual columns of 1/4 of the diameter of a classical EB-PVD type TBC have been deposited. These coatings have the potential to prove a significant reduction in thermal conductivity and in erosion performance. (Abstract Copyright [2006], Wiley Periodicals, Inc.)

  11. Metal (Ag/Ti)-Containing Hydrogenated Amorphous Carbon Nanocomposite Films with Enhanced Nanoscratch Resistance: Hybrid PECVD/PVD System and Microstructural Characteristics.

    Science.gov (United States)

    Constantinou, Marios; Nikolaou, Petros; Koutsokeras, Loukas; Avgeropoulos, Apostolos; Moschovas, Dimitrios; Varotsis, Constantinos; Patsalas, Panos; Kelires, Pantelis; Constantinides, Georgios

    2018-03-30

    This study aimed to develop hydrogenated amorphous carbon thin films with embedded metallic nanoparticles (a-C:H:Me) of controlled size and concentration. Towards this end, a novel hybrid deposition system is presented that uses a combination of Plasma Enhanced Chemical Vapor Deposition (PECVD) and Physical Vapor Deposition (PVD) technologies. The a-C:H matrix was deposited through the acceleration of carbon ions generated through a radio-frequency (RF) plasma source by cracking methane, whereas metallic nanoparticles were generated and deposited using terminated gas condensation (TGC) technology. The resulting material was a hydrogenated amorphous carbon film with controlled physical properties and evenly dispersed metallic nanoparticles (here Ag or Ti). The physical, chemical, morphological and mechanical characteristics of the films were investigated through X-ray reflectivity (XRR), Raman spectroscopy, Scanning Electron Microscopy (SEM), Atomic Force Microscopy (AFM), Transmission Electron Microscopy (TEM) and nanoscratch testing. The resulting amorphous carbon metal nanocomposite films (a-C:H:Ag and a-C:H:Ti) exhibited enhanced nanoscratch resistance (up to +50%) and low values of friction coefficient (<0.05), properties desirable for protective coatings and/or solid lubricant applications. The ability to form nanocomposite structures with tunable coating performance by potentially controlling the carbon bonding, hydrogen content, and the type/size/percent of metallic nanoparticles opens new avenues for a broad range of applications in which mechanical, physical, biological and/or combinatorial properties are required.

  12. Metal (Ag/Ti-Containing Hydrogenated Amorphous Carbon Nanocomposite Films with Enhanced Nanoscratch Resistance: Hybrid PECVD/PVD System and Microstructural Characteristics

    Directory of Open Access Journals (Sweden)

    Marios Constantinou

    2018-03-01

    Full Text Available This study aimed to develop hydrogenated amorphous carbon thin films with embedded metallic nanoparticles (a–C:H:Me of controlled size and concentration. Towards this end, a novel hybrid deposition system is presented that uses a combination of Plasma Enhanced Chemical Vapor Deposition (PECVD and Physical Vapor Deposition (PVD technologies. The a–C:H matrix was deposited through the acceleration of carbon ions generated through a radio-frequency (RF plasma source by cracking methane, whereas metallic nanoparticles were generated and deposited using terminated gas condensation (TGC technology. The resulting material was a hydrogenated amorphous carbon film with controlled physical properties and evenly dispersed metallic nanoparticles (here Ag or Ti. The physical, chemical, morphological and mechanical characteristics of the films were investigated through X-ray reflectivity (XRR, Raman spectroscopy, Scanning Electron Microscopy (SEM, Atomic Force Microscopy (AFM, Transmission Electron Microscopy (TEM and nanoscratch testing. The resulting amorphous carbon metal nanocomposite films (a–C:H:Ag and a–C:H:Ti exhibited enhanced nanoscratch resistance (up to +50% and low values of friction coefficient (<0.05, properties desirable for protective coatings and/or solid lubricant applications. The ability to form nanocomposite structures with tunable coating performance by potentially controlling the carbon bonding, hydrogen content, and the type/size/percent of metallic nanoparticles opens new avenues for a broad range of applications in which mechanical, physical, biological and/or combinatorial properties are required.

  13. Structure and corrosion properties of PVD Cr-N coatings

    International Nuclear Information System (INIS)

    Liu, C.; Bi, Q.; Ziegele, H.; Leyland, A.; Matthews, A.

    2002-01-01

    PVD Cr-N coatings produced by physical vapor deposition (PVD) are increasingly used for mechanical and tribological applications in various industrial sectors. These coatings are particularly attractive for their excellent corrosion resistance, which further enhances the lifetime and service quality of coated components. PVD Cr-N coated steels in an aqueous solution are usually corroded by galvanic attack via through-coating 'permeable' defects (e.g., pores). Therefore, the corrosion performance of Cr-N coated steel is determined by a number of variables of the coating properties and corrosive environment. These variables include: (i) surface continuity and uniformity; (ii) through-coating porosity; (iii) film density and chemical stability; (iv) growth stresses; (v) interfacial and intermediate layers; (vi) coating thickness; (vii) coating composition; and (viii) substrate properties. In this article, PVD Cr-N coatings were prepared, by electron-beam PVD and sputter deposition, with different compositions, thicknesses, and surface roughnesses, by changing the N 2 flow rate, applying multilayering techniques and changing the substrate finish prior to coating. The microstructure of such coatings is investigated by various analytical techniques such as glancing angle x-ray diffraction and scanning electron microscopy, which are also correlated with the corrosion performance of the coated steel. Both dc polarization and ac impedance spectroscopy were employed to investigate the corrosion resistance of Cr-N coated steel in a 0.5N NaCl solution. It has been found that the N 2 flow rate during reactive deposition strongly determines the microstructure of Cr-N coatings (due to the changing nitrogen content in the film) and can thus affect the corrosion resistance of coated systems. The surface finish of the steel substrate also affects the uniformity and coverage of PVD coatings; grooves and inclusions on the original substrate can raise the susceptibility of coated

  14. Development of environmentally compatible tribosystems with PVD-technology

    International Nuclear Information System (INIS)

    Lugscheider, E.; Hornig, T.; Kienitz, S.; Klocke, F.; Krieg, T.

    2001-01-01

    PVD coatings offer a wide variety of applications. The focal point of this work is the development of an advanced type of PVD-hardcoating which allows machining with environmentally compatible lubricants. Representative examples for the investigations are the tribological systems 'turning of quenched and tempered steel 42CrMo4 V' and 'austenitic stainless steel X5CrNi18-10'. Ti-Hf-Cr-N and TiAlN/Al 2 O 3 were deposited by AIP- and H.I.S. TM - process respectively. These coating systems showed best results concerning oxidation wear and abrasive wear in former investigations. This was necessary because main cutting-edge life criterias are oxidation wear and abrasive wear at the minor cutting edge. Consequently, a high oxidation stability and a high hardness at high temperatures are required. (author)

  15. Surface coatings deposited by CVD and PVD

    International Nuclear Information System (INIS)

    Gabriel, H.M.

    1982-01-01

    The demand for wear and corrosion protective coatings is increasing due to economic facts. Deposition processes in gas atmospheres like the CVD and PVD processes attained a tremendous importance especially in the field of the deposition of thin hard refractory and ceramic coatings. CVD and PVD processes are reviewed in detail. Some examples of coating installations are shown and numerous applications are given to demonstrate the present state of the art. (orig.) [de

  16. Latest Developments in PVD Coatings for Tooling

    Directory of Open Access Journals (Sweden)

    Gabriela Strnad

    2010-06-01

    Full Text Available The paper presents the recent developments in the field of PVD coating for manufacturing tools. A review of monoblock, multilayer, nanocomposite, DLC and oxinitride coatings is discussed, with the emphasis on coatings which enables the manufacturers to implement high productivity processes such as high speed cutting and dry speed machining.

  17. PVD TBC experience on GE aircraft engines

    Science.gov (United States)

    Maricocchi, Antonio; Bartz, Andi; Wortman, David

    1995-01-01

    The higher performance levels of modern gas turbine engines present significant challenges in the reliability of materials in the turbine. The increased engine temperatures required to achieve the higher performance levels reduce the strength of the materials used in the turbine sections of the engine. Various forms of thermal barrier coatings (TBC's) have been used for many years to increase the reliability of gas turbine engine components. Recent experience with the physical vapor deposition (PVD) process using ceramic material has demonstrated success in extending the service life of turbine blades and nozzles. Engine test results of turbine components with a 125 micron (0.005 in) PVD TBC have demonstrated component operating temperatures of 56-83 C (100-150 F) lower than non-PVD TBC components. Engine testing has also revealed the TBC is susceptible to high angle particle impact damage. Sand particles and other engine debris impact the TBC surface at the leading edge of airfoils and fracture the PVD columns. As the impacting continues, the TBC erodes away in local areas. Analysis of the eroded areas has shown a slight increase in temperature over a fully coated area, however a significant temperature reduction was realized over an airfoil without TBC.

  18. Microstructural, mechanical and oxidation features of NiCoCrAlY coating produced by plasma activated EB-PVD

    International Nuclear Information System (INIS)

    He, Jian; Guo, Hongbo; Peng, Hui; Gong, Shengkai

    2013-01-01

    NiCoCrAlY coatings produced by electron beam-physical vapor deposition (EB-PVD) have been extensively used as the oxidation resistance coatings or suitable bond coats in thermal barrier coating (TBC) system. However, the inherent imperfections caused by EB-PVD process degrade the oxidation resistance of the coatings. In the present work, NiCoCrAlY coatings were creatively produced by plasma activated electron beam-physical vapor deposition (PA EB-PVD). The novel coatings showed a terraced substructure on the surface of each grain due to the increased energy of metal ions and enhanced mobility of adatoms. Also a strong (1 1 1) crystallographic texture of γ/γ′ grains was observed. The toughness of the coatings got remarkably improved compared with the coatings deposited by conventional EB-PVD and the oxidation behavior at 1373 K showed that the novel coatings had excellent oxidation resistance. The possible mechanism was finally discussed.

  19. Thermal Conductivity of EB-PVD Thermal Barrier Coatings Evaluated by a Steady-State Laser Heat Flux Technique

    Science.gov (United States)

    Zhu, Dongming; Miller, Robert A.; Nagaraj, Ben A.; Bruce, Robert W.

    2000-01-01

    The thermal conductivity of electron beam-physical vapor deposited (EB-PVD) Zr02-8wt%Y2O3 thermal barrier coatings was determined by a steady-state heat flux laser technique. Thermal conductivity change kinetics of the EB-PVD ceramic coatings were also obtained in real time, at high temperatures, under the laser high heat flux, long term test conditions. The thermal conductivity increase due to micro-pore sintering and the decrease due to coating micro-delaminations in the EB-PVD coatings were evaluated for grooved and non-grooved EB-PVD coating systems under isothermal and thermal cycling conditions. The coating failure modes under the high heat flux test conditions were also investigated. The test technique provides a viable means for obtaining coating thermal conductivity data for use in design, development, and life prediction for engine applications.

  20. PVD processes of thin films deposition using Hall-current discharge

    International Nuclear Information System (INIS)

    Svadkovskij, I.V.

    2007-01-01

    Results of research and developments in the field of PVD processes of thin films deposition using Hall-current discharge have been summarized. Effects of interaction of ions with surface during deposition have been considered. Also features of application and prospects of devices based on ion beam and magnetron sputtering systems in thin films technologies have been analyzed. The aspects in the field plasma physics, technology and equipment plasma PVD processes of thin films deposition have been systematized, on the base of investigations made by author and other scientists. (authors)

  1. Crack resistance of pvd coatings : Influence of surface treatment prior to deposition

    NARCIS (Netherlands)

    Zoestbergen, E; de Hosson, J.T.M.

    The crack resistance of three different PVD coatings, TiN, Ti(C,N), and a multilayer system of alternating TiN and TiAlN, have been investigated. The three coating systems were deposited onto substrates with a different surface roughness to study the influence of this pretreatment on the crack

  2. New PVD Technologies for New Ordnance Coatings

    Science.gov (United States)

    2012-04-01

    characteristics using a Tantalum and a Chrome target; 4) Deposition of Ta coatings and reactive deposition of CrN; 5) Deposition parameters affecting film...Vapor Deposition (PVD); High Power Impulse Magnetron Sputtering (HIPIMS); Modulated Pulsed Power (MPP); Tantalum; Chrome ; Ta coatings; CrN; coating...The pre-production chemicals and acids are hazardous and hexavalent Cr is a known carcinogen. Significant annual expenditures are necessary to

  3. Ordered metal nanotube arrays fabricated by PVD.

    Science.gov (United States)

    Marquez, F; Morant, C; Campo, T; Sanz, J M; Elizalde, E

    2010-02-01

    In this work we report a simple method to fabricate ordered arrays of metal nanotubes. This method is based on the deposition of a metal by PVD onto an anodized aluminum oxide (AAO) template. The dimensions of the synthesized nanotubes depend both on the AAO template and on the deposited metal. In fact, it is observed that the aspect ratios of the nanotubes clearly depend significantly on the metal, ranging from 0.6 (Fe) to at least 3 (Zr).

  4. Structure and corrosion properties of PVD Cr-N coatings

    CERN Document Server

    Liu, C; Ziegele, H; Leyland, A; Matthews, A

    2002-01-01

    PVD Cr-N coatings produced by physical vapor deposition (PVD) are increasingly used for mechanical and tribological applications in various industrial sectors. These coatings are particularly attractive for their excellent corrosion resistance, which further enhances the lifetime and service quality of coated components. PVD Cr-N coated steels in an aqueous solution are usually corroded by galvanic attack via through-coating 'permeable' defects (e.g., pores). Therefore, the corrosion performance of Cr-N coated steel is determined by a number of variables of the coating properties and corrosive environment. These variables include: (i) surface continuity and uniformity; (ii) through-coating porosity; (iii) film density and chemical stability; (iv) growth stresses; (v) interfacial and intermediate layers; (vi) coating thickness; (vii) coating composition; and (viii) substrate properties. In this article, PVD Cr-N coatings were prepared, by electron-beam PVD and sputter deposition, with different compositions, t...

  5. Overview of PVD wear resistant coatings

    International Nuclear Information System (INIS)

    Teeter, F.J.

    1999-01-01

    The combined functionality of wear-resistant and low-friction multilayer coatings has widened application possibilities for a new generation of coated tools. For the first time tool wear mechanisms are comprehensively addressed both at the cutting edge and contact areas away from the edge where chip evacuation is facilitated. Since its recent market introduction a combined TiA1N and WC/C PVD coating has been proven to increase cutting performance in various metal cutting operations, notably drilling and tapping of steels and aluminum alloys. Significant improvements have been obtained under dry as well as with coolant conditions. The results of laboratory metal cutting tests and field trials to date will be described. Correlations between chip formation / wear mechanisms and coating properties are given to explain the effectiveness of this coating. (author)

  6. Antibacterial Functionalization of PVD Coatings on Ceramics

    Directory of Open Access Journals (Sweden)

    Javier Osés

    2018-05-01

    Full Text Available The application of surface treatments that incorporate silver or copper as antibacterial elements has become a common practice for a wide variety of medical devices and materials because of their effective activity against nosocomial infections. Ceramic tiles are choice materials for cladding the floors and walls of operation rooms and other hospital spaces. This study is focused on the deposition of biocide physical vapor deposition (PVD coatings on glazed ceramic tiles. The objective was to provide antibacterial activity to the surfaces without worsening their mechanical properties. Silver and copper-doped chromium nitride (CrN and titanium nitride (TiN coatings were deposited on samples of tiles. A complete characterization was carried out in order to determine the composition and structure of the coatings, as well as their topographical and mechanical properties. The distribution of Ag and Cu within the coating was analyzed using glow discharge optical emission spectrometry (GD-OES and field emission scanning electron microscope (FE-SEM. Roughness, microhardness, and scratch resistance were measured for all of the combinations of coatings and dopants, as well as their wettability. Finally, tests of antibacterial efficacy against Staphylococcus aureus and Escherichia coli were carried out, showing that all of the doped coatings had pronounced biocide activity.

  7. Iron-regulated transcription of the pvdA gene in Pseudomonas aeruginosa: effect of Fur and PvdS on promoter activity.

    OpenAIRE

    Leoni, L; Ciervo, A; Orsi, N; Visca, P

    1996-01-01

    The pvdA gene, encoding the enzyme L-ornithine N5-oxygenase, catalyzes a key step of the pyoverdin biosynthetic pathway in Pseudomonas aeruginosa. Expression studies with a promoter probe vector made it possible to identify three tightly iron-regulated promoter regions in the 5.9-kb DNA fragment upstream of pvdA. The promoter governing pvdA expression was located within the 154-bp sequence upstream of the pvdA translation start site. RNA analysis showed that expression of PvdA is iron regulat...

  8. The effect of PVD coatings on the corrosion behaviour of AZ91 magnesium alloy

    International Nuclear Information System (INIS)

    Altun, Hikmet; Sen, Sadri

    2006-01-01

    In this study, multilayered AlN (AlN + AlN + AlN) and AlN + TiN were coated on AZ91 magnesium alloy using physical vapour deposition (PVD) technique of DC magnetron sputtering, and the influence of the coatings on the corrosion behaviour of the AZ91 alloy was examined. A PVD system for coating processes, a potentiostat for electrochemical corrosion tests, X-ray difractometer for compositional analysis of the coatings, and scanning electron microscopy for surface examinations were used. It was determined that PVD coatings deposited on AZ91 magnesium alloy increased the corrosion resistance of the alloy, and AlN + AlN + AlN coating increased the corrosion resistance much more than AlN + TiN coating. However, it was observed that, in the coating layers, small structural defects e.g., pores, pinholes, cracks that could arise from the coating process or substrate and get the ability of protection from corrosion worsened were present

  9. Plasma Spray-Physical Vapor Deposition (PS-PVD) of Ceramics for Protective Coatings

    Science.gov (United States)

    Harder, Bryan J.; Zhu, Dongming

    2011-01-01

    In order to generate advanced multilayer thermal and environmental protection systems, a new deposition process is needed to bridge the gap between conventional plasma spray, which produces relatively thick coatings on the order of 125-250 microns, and conventional vapor phase processes such as electron beam physical vapor deposition (EB-PVD) which are limited by relatively slow deposition rates, high investment costs, and coating material vapor pressure requirements. The use of Plasma Spray - Physical Vapor Deposition (PS-PVD) processing fills this gap and allows thin (deposited and multilayer coatings of less than 100 microns to be generated with the flexibility to tailor microstructures by changing processing conditions. Coatings of yttria-stabilized zirconia (YSZ) were applied to NiCrAlY bond coated superalloy substrates using the PS-PVD coater at NASA Glenn Research Center. A design-of-experiments was used to examine the effects of process variables (Ar/He plasma gas ratio, the total plasma gas flow, and the torch current) on chamber pressure and torch power. Coating thickness, phase and microstructure were evaluated for each set of deposition conditions. Low chamber pressures and high power were shown to increase coating thickness and create columnar-like structures. Likewise, high chamber pressures and low power had lower growth rates, but resulted in flatter, more homogeneous layers

  10. Structure And Properties Of PVD Coatings Deposited On Cermets

    Directory of Open Access Journals (Sweden)

    Żukowska L.

    2015-06-01

    Full Text Available The main aim of the research is the investigation of the structure and properties of single-layer and gradient coatings of the type (Ti,AlN and Ti(C,N deposited by physical vapour deposition technology (PVD on the cermets substrate.

  11. A chemically stable PVD multilayer encapsulation for lithium microbatteries

    International Nuclear Information System (INIS)

    Ribeiro, J F; Sousa, R; Cunha, D J; Vieira, E M F; Goncalves, L M; Silva, M M; Dupont, L

    2015-01-01

    A multilayer physical vapour deposition (PVD) thin-film encapsulation method for lithium microbatteries is presented. Lithium microbatteries with a lithium cobalt oxide (LiCoO 2 ) cathode, a lithium phosphorous oxynitride (LiPON) electrolyte and a metallic lithium anode are under development, using PVD deposition techniques. Metallic lithium film is still the most common anode on this battery technology; however, it presents a huge challenge in terms of material encapsulation (lithium reacts with almost any materials deposited on top and almost instantly begins oxidizing in contact with atmosphere). To prove the encapsulation concept and perform all the experiments, lithium films were deposited by thermal evaporation technique on top of a glass substrate, with previously patterned Al/Ti contacts. Three distinct materials, in a multilayer combination, were tested to prevent lithium from reacting with protection materials and atmosphere. These multilayer films were deposited by RF sputtering and were composed of lithium phosphorous oxide (LiPO), LiPON and silicon nitride (Si 3 N 4 ). To complete the long-term encapsulation after breaking the vacuum, an epoxy was applied on top of the PVD multilayer. In order to evaluate oxidation state of lithium films, the lithium resistance was measured in a four probe setup (cancelling wires/contact resistances) and resistivity calculated, considering physical dimensions. A lithium resistivity of 0.16 Ω μm was maintained for more than a week. This PVD multilayer exonerates the use of chemical vapour deposition (CVD), glove-box chambers and sample manipulation between them, significantly reducing the fabrication cost, since battery and its encapsulation are fabricated in the same PVD chamber. (paper)

  12. A chemically stable PVD multilayer encapsulation for lithium microbatteries

    Science.gov (United States)

    Ribeiro, J. F.; Sousa, R.; Cunha, D. J.; Vieira, E. M. F.; Silva, M. M.; Dupont, L.; Goncalves, L. M.

    2015-10-01

    A multilayer physical vapour deposition (PVD) thin-film encapsulation method for lithium microbatteries is presented. Lithium microbatteries with a lithium cobalt oxide (LiCoO2) cathode, a lithium phosphorous oxynitride (LiPON) electrolyte and a metallic lithium anode are under development, using PVD deposition techniques. Metallic lithium film is still the most common anode on this battery technology; however, it presents a huge challenge in terms of material encapsulation (lithium reacts with almost any materials deposited on top and almost instantly begins oxidizing in contact with atmosphere). To prove the encapsulation concept and perform all the experiments, lithium films were deposited by thermal evaporation technique on top of a glass substrate, with previously patterned Al/Ti contacts. Three distinct materials, in a multilayer combination, were tested to prevent lithium from reacting with protection materials and atmosphere. These multilayer films were deposited by RF sputtering and were composed of lithium phosphorous oxide (LiPO), LiPON and silicon nitride (Si3N4). To complete the long-term encapsulation after breaking the vacuum, an epoxy was applied on top of the PVD multilayer. In order to evaluate oxidation state of lithium films, the lithium resistance was measured in a four probe setup (cancelling wires/contact resistances) and resistivity calculated, considering physical dimensions. A lithium resistivity of 0.16 Ω μm was maintained for more than a week. This PVD multilayer exonerates the use of chemical vapour deposition (CVD), glove-box chambers and sample manipulation between them, significantly reducing the fabrication cost, since battery and its encapsulation are fabricated in the same PVD chamber.

  13. Multilayered and composite PVD-CVD coatings in cemented carbides manufacture

    International Nuclear Information System (INIS)

    Glushkov, V.N.; Anikeev, A.I.; Anikin, V.N.; Vereshchaka, A.S.

    2001-01-01

    Carbide cutting tools with wear-resistant coatings deposited by CVD process are widely employed in mechanical engineering to ensure a substantially longer service life of tool systems. However, the relatively high temperature and long time of the process make the substrate decarburise and, as a result, the bend strength and performance characteristics of a tool decrease. The present study suggests the problem of deteriorated strength of CVD-coated carbide tools be solved by the development of a technology that combines arc-PVD and CVD processes to deposit multilayered coatings of titanium and aluminium compounds. (author)

  14. Thermal cycling behavior of YSZ and La2(Zr0.7Ce0.3)2O7 as double-ceramic-layer systems EB-PVD TBCs

    International Nuclear Information System (INIS)

    Xu Zhenhua; He Limin; Mu Rende; Lu Feng; He Shimei; Cao Xueqiang

    2012-01-01

    Highlights: ► DCL coating has a longer lifetime than that of single layer coating of LZ7C3 or YSZ. ► The unique growth modes of columns within DCL coating. ► The presence of cerium in both Ce 3+ and Ce 4+ oxidation states within the coating surface. ► The spallation of DCL coating induced by transverse cracks may be the first emergence of delamination followed by spalling layer by layer. ► The outward diffusion of Cr element (bond coat) into LZ7C3 layer. - Abstract: Double-ceramic-layer (DCL) thermal barrier coatings (TBCs) of La 2 (Zr 0.7 Ce 0.3 ) 2 O 7 (LZ7C3) and yttria stabilized zirconia (YSZ) were deposited by electron beam-physical vapor deposition (EB-PVD). The thermal cycling test at 1573 K in burner-rig with a coal gas flame indicates the thermal cycling life of DCL coating is not only much longer than that of LZ7C3 coating, but also approximately 27% longer than that of YSZ coating. The superior sintering-resistance of LZ7C3 coating and the unique growth modes of columns within DCL coating are all very helpful to the prolongation of thermal cycling life of DCL coating. The failure of DCL coating is mainly a result of the reduction–oxidation of cerium oxide, the re-crystallization of some LZ7C3 fine grains, the cracks initiation, propagation and extension, the abnormal oxidation of bond coat, the degradation of t′-phase in YSZ coating and the outward diffusion of Cr alloying element into LZ7C3 coating. Since no single material that has been studied so far satisfies all the requirements for high temperature applications, DCL coating is an important development direction of TBCs.

  15. Recubrimientos por PVD decorativos sobre cerámicas

    Directory of Open Access Journals (Sweden)

    García, J. A.

    2006-08-01

    Full Text Available During the last years PVD coatings has been used for decorative purposes on ceramics and other substrates. Standards layers like TiN, CrN, TiCN, etc, give us the possibly of obtaining a wide range of colours, with a good mechanical, chemical properties. This paper gathers the works carried out in the Center of Advance Surface engineering of AIN during the three last years in the field of the decorative coatings. Different layer have been deposited by means of a METAPLAS 232 PVD equipment. A complete chemical and mechanical characterisation have been carried out on the different deposited layers like ultramicroindentation, scratch tests, wear resistance and GDOES.

    En los últimos años se ha venido estudiado la aplicabilidad de las técnicas de depósitos mediante métodos físicos en fase vapor (PVD, para la realización de recubrimientos sobre cerámicas y otros substratos con fines decorativos. Los recubrimientos estándar por PVD como el TiN, CrN, TiCN, etc, ofrecen la posibilidad de conseguir acabados de apariencia metálica, de una amplia gama de colores, y con buenas propiedades mecánicas y químicas, como resistencia a la abrasión, estabilidad térmica, o resistencia a la corrosión. En este trabajo se recogen las experiencias realizadas en el recubrimiento y caracterización de cerámicas decorativas, durante los tres últimos años, en el Centro de Ingeniería de Superficies de la Asociación de la Industria Navarra. Los distintos tipos de recubrimientos se han realizado mediante un equipo de PVD modelo METAPLAS 232, con seis evaporadores de arco eléctrico y sistema de limpieza iónica patentado AEGD. Los recubrimientos han sido caracterizados, tanto química como mecánicamente, empleando las más modernas técnicas tribológicas (ultramicrodureza, scrascth tests, resistencia al desgaste... y espectroscópicas óptica por descarga luminiscente (GDOES. Los resultados obtenidos muestran que las técnicas de PVD son una

  16. Evaluation of interfacial mechanical properties under shear loading in EB-PVD TBCs by the pushout method

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Sang-Seok [Research Center for Advanced Science and Technology, University of Tokyo, Tokyo 153-8904 (Japan); Liu Yufu [Research Center for Advanced Science and Technology, University of Tokyo, Tokyo 153-8904 (Japan); Kagawa, Yutaka [Research Center for Advanced Science and Technology, University of Tokyo, Tokyo 153-8904 (Japan)]. E-mail: kagawa@iis.u-tokyo.ac.jp

    2007-06-15

    A new simple pushout technique for evaluation of interfacial shear mechanical properties in thermal barrier coatings has been developed. The technique is similar to the pushout test of fiber-reinforced ceramics, except for the specimen shape and support method. The technique has been applied to evaluation of interfacial delamination toughness, {gamma} {sub i}, of the electron beam physical vapor deposition (EB-PVD) ZrO{sub 2} thermal barrier coating (TBC) system. The change of {gamma} {sub i} in the EB-PVD system with thermal exposure is measured and discussed in terms of microstructural change and delamination crack path. The measured delamination toughness varied from {gamma} {sub i} = 10 to 115 J/m{sup 2}. The delamination path and TGO growth were found to be closely related. The delamination toughness significantly decreases due to the formation and growth of a spinel phase in the TGO layer. The relation between delamination toughness and delamination behavior is discussed.

  17. PVD Ti coatings on Sm-Co magnets

    International Nuclear Information System (INIS)

    Bovda, O.M.; Bovda, V.O.; Garkusha, I.E.; Leonov, S.O.; Onishchenko, L.V.; Tereshin, V.I.; Totrika, O.S.; Chen, C.H.

    2008-01-01

    The combination of conventional ion-plasma deposition (PVD) and pulsed plasma technologies (PPT) has been applied for rare-earth Sm-Co based magnets, to provide them with enhanced corrosion resistance. The influence of pulsed plasma treatment on Sm-Co magnets with deposited titanium PVD coatings has been investigated. It was revealed that thickness of modified layer significantly depends on the thickness of initial titanium film and plasma treatment regimes. As a result of plasma treatment with energy density of 30 J/cm 2 and pulse duration of ∼ 5 μs fine-grained layer with the thickness of 70 microns has been formed on the Sm-Co magnet with pure titanium film of 50 micron. According to SEM analyses considerable diffusion of titanium to the bulk of the magnet, on the depth of 20 microns, took place. Such reaction enhances strong bonding between the coating and the magnet

  18. Thermal conductivity issues of EB-PVD thermal barrier coatings

    Energy Technology Data Exchange (ETDEWEB)

    Schulz, U.; Raetzer-Scheibe, H.J.; Saruhan, B. [DLR - German Aerospace Center, Institute of Materials Research, 51170 Cologne (Germany); Renteria, A.F. [BTU, Physical Metallurgy and Materials Technology, Cottbus (Germany)

    2007-09-15

    The thermal conductivity of electron-beam physical vapor deposited (EB-PVD) thermal barrier coatings (TBCs) was investigated by the Laser Flash technique. Sample type and methodology of data analyses as well as atmosphere during the measurement have some influence on the data. A large variation of the thermal conductivity was found by changes in TBC microstructure. Exposure at high temperature caused sintering of the porous microstructure that finally increased thermal conductivity up to 30 %. EB-PVD TBCs show a distinct thickness dependence of the thermal conductivity due to the anisotropic microstructure in thickness direction. Thin TBCs had a 20 % lower thermal conductivity than thick coatings. New compositions of the ceramic top layer offer the largest potential to lower thermal conductivity. Values down to 0.8W/(mK) have been already demonstrated with virgin coatings of pyrochlore compositions. (Abstract Copyright [2007], Wiley Periodicals, Inc.) [German] Die Waermeleitfaehigkeit von elektronenstrahl-aufgedampften (EB-PVD) Waermedaemmschichten (TBCs) wurde mittels Laser-Flash untersucht. Probentyp, Messmethodik und die Atmosphaere waehrend der Messung haben einen Einfluss auf die Ergebnisse. Aenderungen in der Mikrostruktur der TBC fuehrten zu grossen Unterschieden der Waermeleitfaehigkeit. Eine Hochtemperaturbelastung verursachte Sintervorgaenge in der poroesen Mikrostruktur, was die Waermeleitfaehigkeit um bis zu 30 % ansteigen liess. EB-PVD TBCs zeigen eine deutliche Dickenabhaengigkeit der Waermeleitfaehigkeit durch die Anisotropie der Mikrostruktur in dieser Richtung. Duenne TBCs haben eine um 20 % geringere Waermeleitfaehigkeit als dicke Schichten. Neue Zusammensetzungen der keramischen Deckschicht bieten die groessten Moeglichkeiten fuer eine Reduktion der Waermeleitfaehigkeit. Werte bis zu 0,8 W/(mK) wurden damit bereits erreicht. (Abstract Copyright [2007], Wiley Periodicals, Inc.)

  19. Thermal cycling behavior of YSZ and La{sub 2}(Zr{sub 0.7}Ce{sub 0.3}){sub 2}O{sub 7} as double-ceramic-layer systems EB-PVD TBCs

    Energy Technology Data Exchange (ETDEWEB)

    Xu Zhenhua, E-mail: zhxuciac@yahoo.com [Beijing Institute of Aeronautical Materials, Department 5, P.O. Box 81-5, Beijing 100095 (China); He Limin; Mu Rende; Lu Feng; He Shimei [Beijing Institute of Aeronautical Materials, Department 5, P.O. Box 81-5, Beijing 100095 (China); Cao Xueqiang [State Key Laboratory of Rare Earth Resource Utilization, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun 130022 (China)

    2012-06-05

    Highlights: Black-Right-Pointing-Pointer DCL coating has a longer lifetime than that of single layer coating of LZ7C3 or YSZ. Black-Right-Pointing-Pointer The unique growth modes of columns within DCL coating. Black-Right-Pointing-Pointer The presence of cerium in both Ce{sup 3+} and Ce{sup 4+} oxidation states within the coating surface. Black-Right-Pointing-Pointer The spallation of DCL coating induced by transverse cracks may be the first emergence of delamination followed by spalling layer by layer. Black-Right-Pointing-Pointer The outward diffusion of Cr element (bond coat) into LZ7C3 layer. - Abstract: Double-ceramic-layer (DCL) thermal barrier coatings (TBCs) of La{sub 2}(Zr{sub 0.7}Ce{sub 0.3}){sub 2}O{sub 7} (LZ7C3) and yttria stabilized zirconia (YSZ) were deposited by electron beam-physical vapor deposition (EB-PVD). The thermal cycling test at 1573 K in burner-rig with a coal gas flame indicates the thermal cycling life of DCL coating is not only much longer than that of LZ7C3 coating, but also approximately 27% longer than that of YSZ coating. The superior sintering-resistance of LZ7C3 coating and the unique growth modes of columns within DCL coating are all very helpful to the prolongation of thermal cycling life of DCL coating. The failure of DCL coating is mainly a result of the reduction-oxidation of cerium oxide, the re-crystallization of some LZ7C3 fine grains, the cracks initiation, propagation and extension, the abnormal oxidation of bond coat, the degradation of t Prime -phase in YSZ coating and the outward diffusion of Cr alloying element into LZ7C3 coating. Since no single material that has been studied so far satisfies all the requirements for high temperature applications, DCL coating is an important development direction of TBCs.

  20. Development and characterization of nano structured hard coatings for high performance tools by using PVD technique

    International Nuclear Information System (INIS)

    Irfan, M.; Alam, S.; Hassan, Z.; Iftikhar, F.; Khadim, S.

    2006-01-01

    No doubt hard coatings nave major applications in high performance cutting tools in order to improve tribological and mechanical properties of these tools since last years. The actual top development in this regard is the development of PVD based AlTiN coatings and their supplementation with nano. layers. In present these nano coatings are replaced by nano composites along with an additional development of Multilayer Nano structured coatings. This PVD based nano structured coating development optimized by process parameters, crystalline structure and deposition in multilayer. These coating are definitely produced by combination of ARC and Sputtering with filtration of arc droplets. It is studied that the properties like oxidation resistance, wear resistance and resistance against chemical reaction may be obtained by alloying additions of different elements. This paper presents different development stages and Process parameters for- producing high performance Nanostructure coatings and including adhesion test by using Kalomax system for determination of adhesion strength of these coatings and coating thickness measurements by using image analyzer system. Results and conclusions are showing the optimum values for better coatings for different applications. (author)

  1. Optimization of hybrid polymer electrolytes with the effect of lithium salt concentration in PEO/PVdF-HFP blends

    Energy Technology Data Exchange (ETDEWEB)

    Pradeepa, P.; Edwin raj, S.; Sowmya, G.; Kalaiselvimary, J.; Ramesh Prabhu, M., E-mail: mkram83@gmail.com

    2016-03-15

    Highlights: • Polymer blends based on PVdF-HFP/PEO were prepared for Li-ion battery applications. • Structural and electrochemical studies were carried out on prepared electrolytes. • The electrolytes can be used as electrolyte in the possible device fabrications. - Abstract: Poly(ethylene oxide) (PEO) 6.25 wt%/poly(vinylidene fluoride-co-hexafluoropropylene) [P(VdF-HFP)] 18.75 wt% blend based electrolyte films containing different concentrations (2–10) wt% of lithium salt were prepared. The miscibility studies have been performed by using X-ray diffraction and Fourier transform infrared spectroscopy. The role of interaction between polymer hosts on conductivity is discussed using the results of a.c. impedance studies. A room temperature conductivity of 2.3912 × 10{sup −4} S cm{sup −1} has been obtained for PEO (6.25)–PVdF-HFP (18.75)–LiClO{sub 4} (8)–PC (67) polymer complex. The temperature dependence of the conductivity of polymer electrolyte seems to obey VTF relation. Electrochemical stability (3.3 V) was observed in the prepared polymer electrolyte. Reduction process and oxidation process of the prepared electrolyte system have also been evaluated by means of cyclic voltammetry. Thermogravimetric analysis results indicate thermal stability of PEO/PVdF-HFP lithium salt complexes. Roughness parameter of the sample having maximum ionic conductivity was studied by AFM. The morphology of the polymer complex is investigated by using SEM.

  2. Methods to improve the PVD coatability of brass by using diffusion barriers

    Science.gov (United States)

    Langer, Bernd

    Previous work involving PVD coatings on brass has used a combination of multilayers consisting of electroplated films like nickel or chromium and deposited decorative PVD coatings like TiN, TiAIN or ZrN systems. The disadvantages of these systems are the combination of wet electrochemistry and high tech vacuum processes. Furthermore the allergic reaction to nickel and the toxic nature of Cr(VI) must be considered.There is a need for intermediate layers to 'seal-off the brass in order to avoid the evaporation of zinc in vacuum using a diffusion barrier. Furthermore the intermediate layers are required to act as a corrosion barrier.This thesis reports on the development of PVD coatings on heat sensitive brass substrate materials utilising ABS technology with Al, CuAl8 and Nb targets as vapour sources.The brass pretreatment includes careful grinding, polishing and cleaning steps as well as steered arc metal ion etching using the above target materials. The coatings are produced at temperatures between 100 and 250°C in the unbalanced magnetron mode, including layers made from Al, Al-Nb, CuA18, CuAl8-Nb and Nb.Scratch adhesion and Rockwell indentation tests are found not to be directly applicable to the system of soft brass and ductile coating(s). Therefore a new classification for both scratch and indentation tests was defined. The best adhesion was shown by the CuA18 coatings on brass. Corrosion tests showed good results for the Al coatings and poor results for the pure Nb coatings directly applied on brass. The best corrosion result was obtained with a CuAl8-Nb layer system. This layer system also offers very good barrier behaviour concerning Zn diffusion.Other investigations like Glow Discharge Optical Emission Spectroscopy (GDOES), Scanning Electron Microscopy (SEM) imaging, Transmission Electron Microscopy (TEM) and X-ray Diffraction (XRD) were undertaken to characterise the new coating systems for brass.

  3. PVD following plasmin but not hyaluronidase: implications for combination pharmacologic vitreolysis therapy.

    Science.gov (United States)

    Wang, Zhi-Liang; Zhang, Xi; Xu, Xun; Sun, Xiao-Dong; Wang, Fang

    2005-01-01

    To study whether intravitreal injection of plasmin + hyaluronidase safely induces posterior vitreous detachment (PVD). Rabbits were randomized into three groups: (A) 20 rabbits, intravitreal injection of plasmin 1 U + hyaluronidase 20 U in balanced salt solution (BSS) 0.1 mL into one eye; (B) 12 rabbits, plasmin alone; (C) 12 rabbits, hyaluronidase alone. The fellow eye of each rabbit was injected BSS 0.1 mL. In Group A, scanning electron microscopy (SEM) was done in four rabbits at 0.5 hour and in four rabbits at 1 hour. After 7 days, all the remaining 36 rabbits received electroretinography, SEM was examined in eight of each group, and immunohistochemistry was done in four of each group. SEM disclosed the eyes of Group A had complete PVD (8/8), Group B partial PVD (7/8), and Group C (8/8) and all the control eyes (24/24) no PVD after 7 days. Partial PVD was found in 4/4 at 0.5 hour and complete PVD was seen in 3/4 at 1 hour in Group A. Immunohistochemistry showed that the amounts of laminin and fibronectin in the vitreoretinal interface were decreased in Group A and B versus the control eyes (P 0.05). Electroretinography showed no changes in any group (P >0.05). Vitreous injection of plasmin + hyaluronidase induced complete PVD with no obvious toxicity. Plasmin induced partial PVD, but hyaluronidase had no effects.

  4. Wear of Shaped Surfaces of PVD Coated Dies for Clinching

    Directory of Open Access Journals (Sweden)

    Miroslav Džupon

    2017-11-01

    Full Text Available A clinching method that uses a simple toolset consisting of a punch and a die, is utilized for joining lightweight materials. This paper is aimed at investigating the wear of the die cavity of a clinching tool. A clinching tool with a specially shaped cavity was used for joining thin hot-dip galvanized steel sheets. Various types of physical vapour deposition (PVD coatings such as ZrN, CrN and TiCN were deposited on the shaped surface of the die using Lateral Rotating Arc-Cathodes technology. Hot-dip galvanized steel sheets were used for testing the clinching tool. The material properties of PVD coatings that were deposited on the shaped part of the clinching die were evaluated. Finite Element Analysis was used to localize the area of the shaped part of the die and the part of surface area of the cylindrical die cavity of ϕ 5.0 mm, in which high contact pressure values were predicted. The prediction of the start of the wear cycle was verified experimentally by the clinching of 300 samples of hot-dip galvanized steel sheets. Unlike the CrN and ZrN coatings, the TiCN coating remained intact on the entire surface of the die.

  5. Raman microscopic studies of PVD deposited hard ceramic coatings

    International Nuclear Information System (INIS)

    Constable, C.P.

    2000-01-01

    PVD hard ceramic coatings grown via the combined cathodic arc/unbalance magnetron deposition process were studied using Raman microscopy. Characteristic spectra from binary, multicomponent, multilayered and superlattice coatings were acquired to gain knowledge of the solid-state physics associated with Raman scattering from polycrystalline PVD coatings and to compile a comprehensive spectral database. Defect-induced first order scattering mechanisms were observed which gave rise to two pronounced groups of bands related to the acoustical (150- 300cm -1 ) and optical (400-7 50cm -1 ) parts of the phonon spectrum. Evidence was gathered to support the theory that the optic modes were mainly due to the vibrations of the lighter elements and the acoustic modes due to the vibrations of the heavier elements within the lattice. A study into the deformation and disordering on the Raman spectral bands of PVD coatings was performed. TiAIN and TiZrN coatings were intentionally damaged via scratching methods. These scratches were then analysed by Raman mapping, both across and along, and a detailed spectral interpretation performed. Band broadening occurred which was related to 'phonon relaxation mechanisms' as a direct result of the breaking up of coating grains resulting in a larger proportion of grain boundaries per-unit-volume. A direct correlation of the amount of damage with band width was observed. Band shifts were also found to occur which were due to the stresses caused by the scratching process. These shifts were found to be the largest at the edges of scratches. The Raman mapping of 'droplets', a defect inherent to PVD deposition processes, found that higher compressive stresses and large amounts of disorder occurred for coating growth onto droplets. Strategies designed to evaluate the ability of Raman microscopy to monitor the extent of real wear on cutting tools were evaluated. The removal of a coating layer and subsequent detection of a base layer proved

  6. Adhesion and interface problems of EB-PVD thermal barrier coatings; Grenzschichtproblematik und Haftung von EB-PVD-Waermedaemmschichtsystemen

    Energy Technology Data Exchange (ETDEWEB)

    Fritscher, K.; Leyens, C. [Deutsche Forschungsanstalt fuer Luft- und Raumfahrt e.V. (DLR), Koeln (Germany). Inst. fuer Werkstoff-Forschung

    1996-12-31

    Loss of adhesion in thermal insulation layers produced by EB-PVD may be caused by surface morphologies or oxide phases resulting from previous process stages, e.g. shot peening, or inappropriate annealing conditions. These undesirable oxide phases are mostly spinels and silicates which pose mechanical problems. Annealing and densification must be modified in order to promote the formation of {alpha}-Al{sub 2}O{sub 3} layers. It may also be possible to avoid certain categories of flaws by changing one material partner (e.g. by using {beta}-NiAl-free adhesive layers). [Deutsch] Die Ursachen der Einbussen der Haftung in WDS-Systemen aus EB-PVD-Fertigung liegen oft in der Ausbildung von Oberflaechenmorphologien oder von Oxidphasen begruendet, die aus den der WDS-Beschichtung vorangehenden Verfahrensschritten wie z.B. des Glasperlstrahlens und von unangemessenen Gluehbedingungen herruehren koennen. Bei diesen unerwuenschten Oxidphasen handelt es sich u.a. um Spinelle und Silikate, die in mechanischer Hinsicht problematisch sind. Glueh- und Verdichtungsroutinen sind entsprechend zu modifizieren, um die Bildung von {alpha}-Al{sub 2}O{sub 3}-Schichten zu foerdern. Moeglicherweise sind gewisse Fehlerkategorien bereits dadurch zu umgehen, dass ein Materialpartner geaendert wird (Beispiel: {beta}-NiAl-freie Haftschichten anwenden). (orig.)

  7. Analysis of influence of different pressure and different depth of pvd on soft foundation treatment

    Science.gov (United States)

    Li, Bin; Wang, XueKui

    2018-02-01

    According to the depth of plastic vertical drainage (pvd), the arrangement mode and the loading mode to analyze the influence of Vacuum preloading near the existing road. An arrangement mode of vacuum preloading to reduce the impact was put forward. The combination of different depth of pvd and loading modes are used to analyze the effect of vacuum preloading treatment and its influence range. The calculations show that the deformation and the influence distance are smaller by using the 40kPa vacuum loading and 41kPa surcharge load preloading. Reducing the depth of the pvd and vacuum combined surcharge preloading can weaken the influence to the existing highway.

  8. Simultaneous Co-deposition of Zn-Mg Alloy Layers on Steel Strip by PVD Process

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Tae Yeob [POSCO Technical Research Laboratories, Gwangyang (Korea, Republic of); Goodenough, Mark [Strategic Marketing, Tata Steel, Warwickshire (United Kingdom)

    2011-12-15

    This is the first release of an interim report on the development of coating technology of Zn-Mg alloy layers on steel strip by EML-PVD (electromagnetic levitation - physical vapor deposition) process in an air-to-air type continuous PVD pilot plant. It intends to introduce a basic principle of the EML-PVD process together with the high speed PVD pilot plant built in Posco. Due to the agitation effect provided by the high frequency induction coil, simultaneous evaporation of Zn and Mg from a droplet could produce alloy coating layers with Mg content of 6% to 12% depending on the composition of the droplet inside the coil. For its superior corrosion resistance, Zn-Mg alloy coated steel would be a very promising material for automotive, electrical appliances, and construction applications.

  9. Simultaneous Co-deposition of Zn-Mg Alloy Layers on Steel Strip by PVD Process

    International Nuclear Information System (INIS)

    Kim, Tae Yeob; Goodenough, Mark

    2011-01-01

    This is the first release of an interim report on the development of coating technology of Zn-Mg alloy layers on steel strip by EML-PVD (electromagnetic levitation - physical vapor deposition) process in an air-to-air type continuous PVD pilot plant. It intends to introduce a basic principle of the EML-PVD process together with the high speed PVD pilot plant built in Posco. Due to the agitation effect provided by the high frequency induction coil, simultaneous evaporation of Zn and Mg from a droplet could produce alloy coating layers with Mg content of 6% to 12% depending on the composition of the droplet inside the coil. For its superior corrosion resistance, Zn-Mg alloy coated steel would be a very promising material for automotive, electrical appliances, and construction applications

  10. Nanograined Net-Shaped Fabrication of Rhenium Components by EB-PVD

    International Nuclear Information System (INIS)

    Singh, Jogender; Wolfe, Douglas E.

    2004-01-01

    Cost-effective net-shaped forming components have brought considerable interest into DoD, NASA and DoE. Electron beam physical vapor deposition (EB-PVD) offers flexibility in forming net-shaped components with tailored microstructure and chemistry. High purity rhenium (Re) components including rhenium-coated graphite balls, Re- plates and tubes have been successfully manufactured by EB-PVD. EB-PVD Re components exhibited sub-micron and nano-sized grains with high hardness and strength as compared to CVD. It is estimated that the cost of Re components manufactured by EB-PVD would be less than the current CVD and powder-HIP Technologies

  11. Fiber damage during the consolidation of PVD Ti-6Al-4V coated NEXTEL 610 trademark alumina fibers

    International Nuclear Information System (INIS)

    Warren, J.; Elzey, D.M.; Wadley, H.N.G.

    1995-01-01

    Titanium matrix composites reinforced with sol-gel synthesized α-alumina fiber tows have attracted interest as a potentially low cost continuous fiber reinforced metal matrix composite system. The authors have conducted a detailed investigation of fiber damage during high temperature consolidation of PVD Ti-6Al-4V metallized sol-gel alumina fiber tows. Using both hot isostatic pressing and interrupted vacuum hot press consolidation cycles, the two principal mechanisms of fiber damage have been experimentally identified to be microbending/fracture and fiber matrix reaction. A time dependent micromechanics model incorporating the evolving geometry and mechanical properties of both the fibers and matrix has been formulated to simulate the fiber bending/failure mechanism in a representative unit cell and explore the effect of fiber strength loss due to reaction with the matrix. This model has been used to design a process cycle that minimizes damage by exploiting the enhanced superplastic deformation of the initially nanocrystalline PVD Ti-6Al-4V matrix

  12. Prevalence of early and late stages of physiologic PVD in emmetropic elderly population.

    Science.gov (United States)

    Schwab, Christoph; Ivastinovic, Domagoj; Borkenstein, Andreas; Lackner, Eva-Maria; Wedrich, Andreas; Velikay-Parel, Michaela

    2012-05-01

    To investigate the early and late stages of posterior vitreous detachment (PVD) in the foveal area in correlation with age and gender. Three hundred and thirty-five emmetropic eyes of 271 Caucasian patients (216 women/119 men) were examined by optical coherence tomography (OCT) and ultrasound (US). Eyes were classified into groups according to the patients age (up to 69.9; 70-74.9; 75-79.9; over 80 years) and to the clinical findings [Vitreous state: Detached in US; Detached in OCT; Foveal adhesion (FA); Attached vitreous]. The mean age was 76 ± 8 ranging from 44 to 89 years in female and 72 ± 10 ranging from 46 to 87 years in male subjects. The vitreous was attached in 32% of all eyes, 18.5% had FA, 18.5% were detached in OCT and 68% were detached in US. While prevalence of FA decreases with increasing age, OCT-diagnosed detachments did not change significantly with age. Between the ages of 70 and 75, an increase in PVD rates occurred. The prevalence of PVD was similar in both genders. Women were significantly older than men in the late-stage PVD in the eyes. The use of OCT and US enabled us to detect a partial or total PVD in 80% of the eyes. A sudden increase in late-stage PVD between the ages of 70 and 75 was observed, correlating with the reported age prevalence of various macular diseases. In contrast to myopics, both genders of elderly emmetropics have a similar prevalence of PVD. © 2011 The Authors. Acta Ophthalmologica © 2011 Acta Ophthalmologica Scandinavica Foundation.

  13. Adaptive PVD Steganography Using Horizontal, Vertical, and Diagonal Edges in Six-Pixel Blocks

    Directory of Open Access Journals (Sweden)

    Anita Pradhan

    2017-01-01

    Full Text Available The traditional pixel value differencing (PVD steganographical schemes are easily detected by pixel difference histogram (PDH analysis. This problem could be addressed by adding two tricks: (i utilizing horizontal, vertical, and diagonal edges and (ii using adaptive quantization ranges. This paper presents an adaptive PVD technique using 6-pixel blocks. There are two variants. The proposed adaptive PVD for 2×3-pixel blocks is known as variant 1, and the proposed adaptive PVD for 3×2-pixel blocks is known as variant 2. For every block in variant 1, the four corner pixels are used to hide data bits using the middle column pixels for detecting the horizontal and diagonal edges. Similarly, for every block in variant 2, the four corner pixels are used to hide data bits using the middle row pixels for detecting the vertical and diagonal edges. The quantization ranges are adaptive and are calculated using the correlation of the two middle column/row pixels with the four corner pixels. The technique performs better as compared to the existing adaptive PVD techniques by possessing higher hiding capacity and lesser distortion. Furthermore, it has been proven that the PDH steganalysis and RS steganalysis cannot detect this proposed technique.

  14. 7YSZ coating prepared by PS-PVD based on heterogeneous nucleation

    Directory of Open Access Journals (Sweden)

    Ziqian DENG

    2018-04-01

    Full Text Available Plasma spray-physical vapor deposition (PS-PVD as a novel coating process based on low-pressure plasma spray (LPPS has been significantly used for thermal barrier coatings (TBCs. A coating can be deposited from liquid splats, nano-sized clusters, and the vapor phase forming different structured coatings, which shows obvious advantages in contrast to conventional technologies like atmospheric plasma spray (APS and electron beam-physical vapor deposition (EB-PVD. In addition, it can be used to produce thin, dense, and porous ceramic coatings for special applications because of its special characteristics, such as high power, very low pressure, etc. These provide new opportunities to obtain different advanced microstructures, thus to meet the growing requirements of modern functional coatings. In this work, focusing on exploiting the potential of gas-phase deposition from PS-PVD, a series of 7YSZ coating experiments with various process conditions was performed in order to better understand the deposition process in PS-PVD, where coatings were deposited on different substrates including graphite and zirconia. Meanwhile, various substrate temperatures were investigated for the same substrate. As a result, a deposition mechanism of heterogeneous nucleation has been presented showing that surface energy is an important influencing factor for coating structures. Besides, undercooling of the interface between substrate and vapor phase plays an important role in coating structures. Keywords: 7YSZ, Deposition mechanism, Heterogeneous nucleation, PS-PVD, TBC

  15. Comparative study of dlc coatings by pvd against cvd technique on textile dents

    International Nuclear Information System (INIS)

    Malik, M.; Alam, S.; Iftikhar, F.

    2007-01-01

    Diamond like Carbon (DLC) film is a hard amorphous carbon hydride film formed by Physical or Chemical vapor deposition (PVD or CVD) techniques. Due to its unique properties especially high hardness, lower coefficient of friction and lubricious nature, these coatings are not only used to extend the life of cutting tools but also for non cutting applications such as for forming dies, molds and on many functional parts of textile. In the present work two techniques were employed i.e. PVD and CVD for deposition of diamond like carbon film on textile dents. These dents are used as thread guider in high speed weaving machine. The measurement of coating thickness, adhesion, hardness and roughness values indicates that overall properties of DLC coating developed by PVD LARC technology reduces abrasion and increases the workability and durability of textile dents as well as suppress the need of lubricants. (author)

  16. Life assessment of PVD based hard coatings by linear sweep voltammetry for high performance industrial application

    International Nuclear Information System (INIS)

    Malik, M.; Alam, S.; Irfan, M.; Hassan, Z.

    2006-01-01

    PVD based hard coatings have remarkable achievements in order to improve Tribological and surface properties of coating tools and dies. As PVD based hard coatings have a wide range of industrial applications especially in aerospace and automobile parts where they met different chemical attacks and in order to improve industrial performance these coatings must provide an excellent resistance against corrosion, high temperature oxidation and chemical reaction. This paper focuses on study of behaviour of PVD based hard coatings under different corrosive environments like as H/sub 2/SO/sub 4/, HCl, NaCl, KCl, NaOH etc. Corrosion rate was calculate under linear sweep voltammetry method where the Tafel extrapolation curves used for continuously monitoring the corrosion rate. The results show that these coatings have an excellent resistance against chemical attack. (author)

  17. Multilayer stacks obtained by ion assisted EB PVD aimed at thermal barrier coating

    Energy Technology Data Exchange (ETDEWEB)

    Roos, E.; Maile, K.; Lyutovich, A. [Stuttgart Univ. (DE). Materialpruefungsanstalt (MPA)

    2010-07-01

    Thermal Barrier Coating (TBC) using Electron Beam Physical Vapour Deposition (EB PVD) is widely implemented, especially for aero-engine turbine blades. Generally, multilayer stacks are used for these aims. For the additional improvement of intermediate layers with graded transitions to the initial Ni-based alloy, the use of accelerated ions in the EBPVD-process is advantageous. The effect of the substrate bias potential, ion current density and deposition temperature on the structure and properties of Ti and Zr intermediate layers are investigated. The morphology of the films is studied using optical microscopy, scanning electron microscopy (SEM) and atomic force microscopy (AFM). It is found that the surface morphology becomes smoother with rising bias potential and decreasing ion current density. Measurements of Vicker's micro-hardness performed on these coatings have shown its increase with higher values of the bias and its reduction with the growing temperature. This effect is caused by the observed decrease in grain size and higher porosity of the films. A multilayer coating system Ni (based substrate)-Si-Si{sub x}Al{sub y}-Al with graded transitions between the layers is obtained using ion assisted EBPVD. Architecture of a multilayer stack for TBC with graded transitions is proposed. (orig.)

  18. Interfacial fatigue stress in PVD TiN coated tool steels under rolling contact fatigue conditions

    OpenAIRE

    Carvalho, N.J.M.; Huis in ’t Veld, A.J.; Hosson, J.Th. De

    1998-01-01

    Titanium–nitrogen (TiN) films were Physical Vapour Deposited (PVD) on tool steel substrates with different hardness and surface roughness, in a Bai 640R unit using a triode ion plating (e-gun) with a high plasma density. The coated substrates were submitted to a rolling contact fatigue test technique (modified pin-on-ring test) to obtain some clarifications of the mechanism of interfacial failure. Tests were run using PVD-coated rings finished by polishing or grinding to produce different sur...

  19. Properties of Pd nanograins in C-Pd composite films obtained by PVD method

    Directory of Open Access Journals (Sweden)

    Kozłowski M.

    2015-09-01

    Full Text Available Properties of palladium nanograins obtained by sedimentation of a soluted C-Pd film prepared by PVD method are presented. These properties were studied using SEM and TEM methods. Dissolved films were prepared by PVD method and after dissolving, they were fractionated to obtain different parts classified with palladium nanograins diameters. Several classes of diameters were determined: below 20 nm, between 20 and 100 nm and above 100 nm. The defects and triple junction were observed. Multishell carbonaceous structures were found in the big and medium size Pd nanograins.

  20. PVD-Alumina Coatings on Cemented Carbide Cutting Tools: A Study About the Effect on Friction and Adhesion Mechanism

    Directory of Open Access Journals (Sweden)

    S.E. Cordes

    2012-03-01

    Full Text Available Crystalline PVD γ-alumina coatings are interesting for machining operations due to their outstanding characteristics, such as high hot hardness, high thermal stability and low tendency to adhesion. In the present work (Ti,AlN/γ-Al2O3-coatings are deposited on cemented carbide by means of MSIP. Objectives of this work are to study the effects of coating and cutting fluid regarding friction in tribological tests and to study the wear mechanisms and cutting performance of γ-Al2O3-based coated cemented carbide cutting tools in machining operations of austenitic stainless steels. Based on the remarkable properties of the coating system the performance of the cutting tools is increasing significantly.

  1. Challenging metastatic breast cancer with the natural defensin PvD1.

    Science.gov (United States)

    Figueira, Tiago N; Oliveira, Filipa D; Almeida, Inês; Mello, Érica O; Gomes, Valdirene M; Castanho, Miguel A R B; Gaspar, Diana

    2017-11-09

    Metastatic breast cancer is a very serious life threatening condition that poses many challenges for the pharmaceutical development of effective chemotherapeutics. As the therapeutics targeted to the localized masses in breast improve, metastatic lesions in the brain slowly increase in their incidence compromising successful treatment outcomes overall. The blood-brain-barrier (BBB) is one important obstacle for the management of breast cancer brain metastases. New therapeutic approaches are in demand for overcoming the BBB's breaching by breast tumor cells. In this work we demonstrate the potential dual role of a natural antimicrobial plant defensin, PvD 1 : it interferes with the formation of solid tumors in the breast and concomitantly controls adhesion of breast cancer cells to human brain endothelial cells. We have used a combination of techniques that probe PvD 1 's effect at the single cell level and reveal that this peptide can effectively damage breast tumor cells, leaving healthy breast and brain cells unaffected. Results suggest that PvD1 quickly internalizes in cancer cells but remains located in the membrane of normal cells with no significant damage to its structure and biomechanical properties. These interactions in turn modulate cell adhesiveness between tumor and BBB cells. PvD 1 is a potential template for the design of innovative pharmacological approaches for metastatic breast cancer treatment: the manipulation of the biomechanical properties of tumor cells that ultimately prevent their attachment to the BBB.

  2. Interfacial fatigue stress in PVD TiN coated tool steels under rolling contact fatigue conditions

    NARCIS (Netherlands)

    Carvalho, N.J.M.; Huis in 't Veld, A.J.; Hosson, J.T. de

    1998-01-01

    Titanium-nitrogen (TiN) films were Physical Vapour Deposited (PVD) on tool steel substrates with different hardness and surface roughness, in a Bai 640R unit using a triode ion plating (e-gun) with a high plasma density. The coated substrates were submitted to a rolling contact fatigue test

  3. Interfacial fatigue stress in PVD TiN coated tool steels under rolling contact fatigue conditions

    NARCIS (Netherlands)

    Carvalho, N.J.M.; Huis in ’t Veld, A.J.; Hosson, J.Th. De

    1998-01-01

    Titanium–nitrogen (TiN) films were Physical Vapour Deposited (PVD) on tool steel substrates with different hardness and surface roughness, in a Bai 640R unit using a triode ion plating (e-gun) with a high plasma density. The coated substrates were submitted to a rolling contact fatigue test

  4. Microstructural investigations of interfaces in PVD TiN coated tool steels

    NARCIS (Netherlands)

    Carvalho, NJM; in't Veld, AJH; De Hosson, JTM; Lejcek, P; Paidar,

    1999-01-01

    The microstructure of PVD TiN coated tools steels composites has been investigated by scanning electron microscopy (SEM) and transmission electron microscopy (TEM). It was found that the microstructure of the coatings consists of a dense fibrous structure typical of a zone T structure. When the

  5. Thermocyclic behaviour of microstructurally modified EB-PVD thermal barrier coatings

    International Nuclear Information System (INIS)

    Schulz, U.; Fritscher, K.; Raetzer-Scheibe, H.-J.; Kaysser, W.A.; Peters, M.

    1997-01-01

    This paper focuses on the combined effects of substrate temperature and rotation during electron-beam physical vapor deposition (EB-PVD) on the columnar microstructure of yttria partially stabilized zirconia (YPSZ) thermal barrier coatings. Diameter and degree of ordering of the columns and the density of the coatings are sensitive to the processing parameters. Results are discussed in the frame of common structural zone models for PVD processes. The models are extended to consider the rotational effect. EB-PVD YPSZ TBCs of different column diameters were deposited on top of an EB-PVD NiCoCrAlY bondcoat on IN 100 superalloy test bars. The performance of the TBCs was investigated in a cyclic oxidation furnace test rig between 1100 C and 130 C and in a burner rig under hot gas corrosion conditions at a maximum temperature of 900 C. Results showed a correlation between cyclic lifetime and the various microstructures of the TBCs. Samples having a non-regular arrangement of columns performed best in both tests. (orig.)

  6. EB-PVD process management for highly productive zirconia thermal barrier coating of turbine blades

    International Nuclear Information System (INIS)

    Reinhold, E.; Botzler, P.; Deus, C.

    1999-01-01

    Zirconia thermal barrier coatings are well used in the turbine manufacturing industry because they ensure extended lifetimes of turbine blades. Compared with other techniques, EB-PVD processes are best suited for the deposition on turbine blades with regard to the layer properties. Therefore EB-PVD coaters for turbine blades are becoming increasingly interesting. The coating costs per component are mainly dependent on a highly productive solution for the deposition task. Thus the EB-PVD process management has to be optimized in order to meet the productivity requirements of the manufacturers. This includes the requirement of high deposition rates, large deposition areas, long time stable production cycles as well as a matched duration of preheating, deposition and cooling down per charge. Modern EB-PVD solutions to be introduced allow deposition rates on blades up to 7 μm/min. The consequences for the technological process management and plant design concerning long time stable coating cycles with high productivity will be discussed. (orig.)

  7. Performance of a dual-process PVD/PS tungsten coating structure under deuterium ion irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Hyunmyung; Lee, Ho Jung; Kim, Sung Hwan [Department of Nuclear and Quantum Engineering, KAIST, Daejeon (Korea, Republic of); Song, Jae-Min [Department of Nuclear Engineering, Seoul National University, Seoul (Korea, Republic of); Jang, Changheui, E-mail: chjang@kaist.ac.kr [Department of Nuclear and Quantum Engineering, KAIST, Daejeon (Korea, Republic of)

    2016-11-01

    Highlights: • D{sup +} irradiation performance of a dual-process PVD/PS W coating was evaluated. • Low-energy plasmas exposure of 100 eV D{sup +} with 1.17 × 10{sup 21} D/s{sup −1} m{sup 2} flux was applied. • After D ion irradiation, flakes were observed on the surface of the simple PS coating. • While, sub-μm size protrusions were observed for dual-process PVD/PS W coating. • Height of D spike in depth profile was lower for dual-process PVD/PS W coating. - Abstract: A dual-process coating structure was developed on a graphite substrate to improve the performance of the coating structure under anticipated operating condition of fusion devices. A thin multilayer W/Mo coating (6 μm) was deposited by physical vapor deposition (PVD) method with a variation of Mo interlayer thickness on plasma spray (PS) W coating (160 μm) of a graphite substrate panel. The dual-process PVD/PS W coatings then were exposed to 3.08 × 10{sup 24} D m{sup −2} of 100 eV D ions with a flux of 1.71 × 10{sup 21} D m{sup −2} s{sup −1} in an electron cyclotron resonance (ECR) chamber. After irradiation, surface morphology and D depth profiles of the dual-process coating were analyzed and compared to those of the simple PS W coating. Both changes in surface morphology and D retention were strongly dependent on the microstructure of surface coating. Meanwhile, the existence of Mo interlayer seemed to have no significant effect on the retention of deuterium.

  8. Production of AlN films: ion nitriding versus PVD coating

    International Nuclear Information System (INIS)

    Figueroa, U.; Salas, O.; Oseguera, J.

    2004-01-01

    The properties of AlN render this material very attractive for optical, electronic, and tribological applications; thus, a great interest exists for the production of thin AlN films on a variety of substrates. Many methods have been developed for this purpose where two processes stand out: plasma-assisted nitriding (PAN) and PVD coating. In the present paper, we compare the processing advantages and disadvantages of both methods in terms of the characteristics of the layers formed. AlN production by ion nitriding is very sensitive to presputtering cleaning and working pressure. Layers several micrometers thick can be produced in a few hours, which are formed by a fine mixture of Al+AlN. The surface morphology of the layers is rather rough. On the other hand, formation of PVD AlN coatings by DC reactive magnetron sputtering is more readily performed and better controlled than in ion nitriding. PVD results in macroscopically smoother AlN films and with similar thickness than the ion nitrided layers but produced in shorter processing times. The morphology of the PVD AlN layers is columnar with a fairly flat surface. Mechanisms for the formation of both types of AlN layers are proposed. One of the main differences between the two processes that explain the different AlN layer morphologies is the energy of the particles that arrive at the substrate. Considering only the processing advantages and the morphology of the AlN layers formed, PVD performs better than PAN processing

  9. Anisotropic TGO rumpling in EB-PVD thermal barrier coatings under in-phase thermomechanical loading

    Energy Technology Data Exchange (ETDEWEB)

    Balint, D.S., E-mail: d.balint@imperial.ac.uk [Department of Mechanical Engineering, Imperial College London, London SW7 2AZ (United Kingdom); Kim, S.-S.; Liu Yufu; Kitazawa, R.; Kagawa, Y. [Research Center for Advanced Science and Technology, University of Tokyo, 4-6-1 Komaba, Meguro-ku, Tokyo 153-8409 (Japan); Evans, A.G. [College of Engineering, University of California, Santa Barbara, CA 93106 (United States)

    2011-04-15

    An electron beam physical vapor deposited (EB-PVD) Y{sub 2}O{sub 3}-ZrO{sub 2} thermal barrier system has been tested under in-phase thermomechanical fatigue (TMF) conditions with thermal gradient in the through-thickness direction. Undulations in the thermally grown oxide (TGO) were observed to have clear anisotropic behavior with respect to the directions parallel and perpendicular to the loading axis. It was found that undulation wavelengths were nearly the same in both directions but the amplitude in the perpendicular direction was much larger than in the parallel direction. A recent model of TGO rumpling was adapted and used to analyze and explain the origins of the observed rumpling behavior under TMF conditions. Methods for deducing variation in the coefficient of thermal expansion with temperature and in the creep properties of the substrate from the experimental strain data are also presented in the course of the derivations. Model results show that tensile stress applied in the loading direction can overcome the compression occurring from lateral expansion during oxide formation, causing undulations to flatten; undulations perpendicular to the loading axis are unaffected. However, ratcheting in the strain cycle experienced by the substrate, which occurs naturally by substrate creep, is necessary for anisotropic rumpling under cyclic stress conditions. Model predictions for constant applied stress are also presented, demonstrating a reversal in the direction of undulation alignment under compression. A threshold stress is identified, in both tension and compression, sufficient to produce appreciable anisotropic rumpling. The model predictions provide a clear mechanism for the anisotropy and further evidence that the lateral expansion strain in the oxide is the driving force for oxide rumpling.

  10. Effect of Annealing Temperature on the Water Contact Angle of PVD Hard Coatings

    Science.gov (United States)

    Yang, Yu-Sen; Cho, Ting-Pin

    2013-01-01

    Various PVD (physical vapor deposition) hard coatings including nitrides and metal-doped diamond-like carbons (Me-DLC) were applied in plastic injection and die-casting molds to improve wear resistance and reduce sticking. In this study, nitrides hcp-AlN (hexagonal close-packed AlN), Cr2N, (CrAl)2N) and Me-DLC (Si-DLC and Cr-DLC) coatings were prepared using a closed field unbalanced magnetron reactive sputtering system. The coatings were annealed in air for 2 h at various temperatures, after which the anti-sticking properties were assessed using water contact angle (WCA) measurements. The as-deposited hcp-AlN, Cr2N and (CrAl)2N coatings exhibit hydrophobic behavior and exhibit respective WCAs of 119°, 106° and 101°. The as-deposited Si-DLC and Cr-DLC coatings exhibit hydrophilic behavior and exhibit respective WCAs of 74° and 88°. The annealed Cr2N and (CrAl)2N coatings exhibit hydrophobic behavior with higher WCAs, while the annealed hcp-AlN, Si-DLC and Cr-DLC coatings are hydrophilic. The increased WCA of the annealed Cr2N and (CrAl)2N coatings is related to their crystal structure and increased roughness. The decreased WCA of the annealed hcp-AlN, Si-DLC and Cr-DLC coatings is related to their crystal structures and has little correlation with roughness. PMID:28811440

  11. Effect of Annealing Temperature on the Water Contact Angle of PVD Hard Coatings.

    Science.gov (United States)

    Yang, Yu-Sen; Cho, Ting-Pin

    2013-08-07

    Various PVD (physical vapor deposition) hard coatings including nitrides and metal-doped diamond-like carbons (Me-DLC) were applied in plastic injection and die-casting molds to improve wear resistance and reduce sticking. In this study, nitrides hcp-AlN (hexagonal close-packed AlN), Cr₂N, (CrAl)₂N) and Me-DLC (Si-DLC and Cr-DLC) coatings were prepared using a closed field unbalanced magnetron reactive sputtering system. The coatings were annealed in air for 2 h at various temperatures, after which the anti-sticking properties were assessed using water contact angle (WCA) measurements. The as-deposited hcp-AlN, Cr₂N and (CrAl)₂N coatings exhibit hydrophobic behavior and exhibit respective WCAs of 119°, 106° and 101°. The as-deposited Si-DLC and Cr-DLC coatings exhibit hydrophilic behavior and exhibit respective WCAs of 74° and 88°. The annealed Cr₂N and (CrAl)₂N coatings exhibit hydrophobic behavior with higher WCAs, while the annealed hcp-AlN, Si-DLC and Cr-DLC coatings are hydrophilic. The increased WCA of the annealed Cr₂N and (CrAl)₂N coatings is related to their crystal structure and increased roughness. The decreased WCA of the annealed hcp-AlN, Si-DLC and Cr-DLC coatings is related to their crystal structures and has little correlation with roughness.

  12. Anisotropic TGO rumpling in EB-PVD thermal barrier coatings under in-phase thermomechanical loading

    International Nuclear Information System (INIS)

    Balint, D.S.; Kim, S.-S.; Liu Yufu; Kitazawa, R.; Kagawa, Y.; Evans, A.G.

    2011-01-01

    An electron beam physical vapor deposited (EB-PVD) Y 2 O 3 -ZrO 2 thermal barrier system has been tested under in-phase thermomechanical fatigue (TMF) conditions with thermal gradient in the through-thickness direction. Undulations in the thermally grown oxide (TGO) were observed to have clear anisotropic behavior with respect to the directions parallel and perpendicular to the loading axis. It was found that undulation wavelengths were nearly the same in both directions but the amplitude in the perpendicular direction was much larger than in the parallel direction. A recent model of TGO rumpling was adapted and used to analyze and explain the origins of the observed rumpling behavior under TMF conditions. Methods for deducing variation in the coefficient of thermal expansion with temperature and in the creep properties of the substrate from the experimental strain data are also presented in the course of the derivations. Model results show that tensile stress applied in the loading direction can overcome the compression occurring from lateral expansion during oxide formation, causing undulations to flatten; undulations perpendicular to the loading axis are unaffected. However, ratcheting in the strain cycle experienced by the substrate, which occurs naturally by substrate creep, is necessary for anisotropic rumpling under cyclic stress conditions. Model predictions for constant applied stress are also presented, demonstrating a reversal in the direction of undulation alignment under compression. A threshold stress is identified, in both tension and compression, sufficient to produce appreciable anisotropic rumpling. The model predictions provide a clear mechanism for the anisotropy and further evidence that the lateral expansion strain in the oxide is the driving force for oxide rumpling.

  13. C. elegans bicd-1, homolog of the Drosophila dynein accessory factor Bicaudal D, regulates the branching of PVD sensory neuron dendrites.

    Science.gov (United States)

    Aguirre-Chen, Cristina; Bülow, Hannes E; Kaprielian, Zaven

    2011-02-01

    The establishment of cell type-specific dendritic arborization patterns is a key phase in the assembly of neuronal circuitry that facilitates the integration and processing of synaptic and sensory input. Although studies in Drosophila and vertebrate systems have identified a variety of factors that regulate dendrite branch formation, the molecular mechanisms that control this process remain poorly defined. Here, we introduce the use of the Caenorhabditis elegans PVD neurons, a pair of putative nociceptors that elaborate complex dendritic arbors, as a tractable model for conducting high-throughput RNAi screens aimed at identifying key regulators of dendritic branch formation. By carrying out two separate RNAi screens, a small-scale candidate-based screen and a large-scale screen of the ~3000 genes on chromosome IV, we retrieved 11 genes that either promote or suppress the formation of PVD-associated dendrites. We present a detailed functional characterization of one of the genes, bicd-1, which encodes a microtubule-associated protein previously shown to modulate the transport of mRNAs and organelles in a variety of organisms. Specifically, we describe a novel role for bicd-1 in regulating dendrite branch formation and show that bicd-1 is likely to be expressed, and primarily required, in PVD neurons to control dendritic branching. We also present evidence that bicd-1 operates in a conserved pathway with dhc-1 and unc-116, components of the dynein minus-end-directed and kinesin-1 plus-end-directed microtubule-based motor complexes, respectively, and interacts genetically with the repulsive guidance receptor unc-5.

  14. Lithium ion conducting PVA:PVdF polymer electrolytes doped with nano SiO2 and TiO2 filler

    Science.gov (United States)

    Hema, M.; Tamilselvi, P.

    2016-09-01

    The effect of nano SiO2 and TiO2 fillers on the thermal, mechanical and electrochemical properties of PVA:PVdF:LiCF3SO3 have been investigated by three optimized systems of SPE (80PVA:20PVdF:15LiCF3SO3), CPE-I (SPE:8SiO2) and CPE-II (SPE:4TiO2). From the TGA curve least weight loss has been observed for CPE-II indicating high thermal stability compared to other systems. Stress-strain curve of the prepared samples confirm the enhancement of tensile strength in CPE-II compared to CPE-I and SPE. Conductivity studies show that addition of TiO2 filler slightly enhances ionic conductivity 3.7×10-3 S cm-1 compared to filler free system at 303 K. Dielectric plots have been analyzed and CPE-II possesses higher dielectric constant compared to CPE-I and filler free system. Temperature dependence of modulus plots has been studied for highest conductivity possessing sample. Wider electrochemical stability has been obtained for nano-composite polymer electrolytes. The results conclude that the prepared CPE-II shows the best performance and it will be well suited for lithium ion batteries.

  15. Identification of residues of FpvA involved in the different steps of Pvd-Fe uptake in Pseudomonas aeruginosa.

    Science.gov (United States)

    Nader, Mirella; Dobbelaere, Wim; Vincent, Michel; Journet, Laure; Adams, Hendrik; Cobessi, David; Gallay, Jacques; Schalk, Isabelle J

    2007-10-23

    FpvA is an outer membrane transporter involved in iron uptake by the siderophore pyoverdine (Pvd) in Pseudomonas aeruginosa. This transporter, like all other proteins of the same family, consists of a transmembrane 22 beta-stranded barrel occluded by a plug domain. The beta-strands of the barrel are connected by large extracellular loops and short periplasmic turns. Site-directed mutagenesis was carried out on FpvA to identify the extracellular loops or parts of these loops involved in the various stages of Pvd-Fe uptake. The G286C, W362C, and W434C mutations in loops L1, L3, and L4, respectively, disturbed the binding of the apo siderophore, as shown by time-resolved fluorescence spectroscopy. Iron uptake experiments followed by fluorescence resonance energy transfer (FRET) or using 55Fe indicated that residues W434 and G701 and, therefore, loops L4 and L9 must be involved in Pvd-Fe uptake by FpvA. The two corresponding mutants incorporated smaller than normal amounts of 55Fe into cells, and no Pvd recycling on FpvA was observed after iron release. Surprisingly, the S603C mutation in loop L7 increased the amount of Pvd-Fe transported. Our results suggest that W434 (L4), S603 (L7), and G701 (L9) are involved in the mechanism of Pvd-Fe uptake.

  16. Thermal cycling behaviour of lanthanum zirconate as EB-PVD thermal barrier coating

    International Nuclear Information System (INIS)

    Bobzin, K.; Lugscheider, E.; Bagcivan, N.

    2006-01-01

    Thermal cycling tests with two different EB-PVD thermal barrier coatings (TBC) were performed in a furnace cycle test. The results of these tests showed an increase of endurable cycle number when pyrochloric La 2 Zr 2 O 7 was used as TBC. 1865 cycles were reached with La 2 Zr 2 O 7 and 1380 cycles with 7 weigth-% yttria stabilised zirconia (YSZ) EB-PVD TBC. Additional investigation was made with scanning electron microscope (SEM) to investigate morphology and to determine chemical composition by electron dispersive x-ray spectroscopy (EDS) analysis. X-Ray diffraction was performed to analyze structural constitution of deposited coatings. (Abstract Copyright [2006], Wiley Periodicals, Inc.)

  17. Depth-resolved X-ray residual stress analysis in PVD (Ti, Cr) N hard coatings

    CERN Document Server

    Genzel, C

    2003-01-01

    Physical vapour deposition (PVD) of thin hard coatings on TiN basis is usually performed at rather low temperatures (T sub D < 500 C) far from thermal equilibrium, which leads to high intrinsic residual stresses in the growing film. In contrast to the extrinsic thermal residual stresses which can easily be estimated from the difference of the coefficients of thermal expansion between the substrate and the coating, a theoretical prediction of the intrinsic residual stresses is difficult, because their amount as well as their distribution within the film depend in a very complex way on the deposition kinetics. By the example of strongly fibre-textured PVD (Ti, Cr)N coatings which have been prepared under defined variation of the deposition parameters in order to adjust the residual stress distribution within the coatings, the paper compares different X-ray diffraction techniques with respect to their applicability for detecting residual stresses which are non-uniform over the coating thickness. (orig.)

  18. Electrospun PVdF-based fibrous polymer electrolytes for lithium ion polymer batteries

    International Nuclear Information System (INIS)

    Kim, Jeong Rae; Choi, Sung Won; Jo, Seong Mu; Lee, Wha Seop; Kim, Byung Chul

    2004-01-01

    This paper discusses the preparation of microporous fibrous membranes from PVdF solutions with different polymer contents, using the electrospinning technique. Electrospun PVdF-based fibrous membranes with average fiber diameters (AFD's) of 0.45-1.38 μm have an apparent porosity and a mean pore size (MPS) of 80-89% and 1.1-4.3 μm, respectively. They exhibited a high uptake of the electrolyte solution (320-350%) and a high ionic conductivity of above 1 x 10 -3 s/cm at room temperature. Their ionic conductivity increased with the decrease in the AFD of the fibrous membrane due to its high electrolyte uptake. The interaction between the electrolyte molecules and the PVdF with a high crystalline content may have had a minor effect on the lithium ion transfer in the fibrous polymer electrolyte, unlike in a nanoporous gel polymer electrolyte. The fibrous polymer electrolyte that contained a 1 M LiPF 6 -EC/DMC/DEC (1/1/1 by weight) solution showed a high electrochemical stability of above 5.0 V, which increased with the decrease in the AFD The interfacial resistance (R i ) between the polymer electrolyte and the lithium electrode slightly increased with the storage time, compared with the higher increase in the interfacial resistance of other gel polymer electrolytes. The prototype cell (MCMB/PVdF-based fibrous electrolyte/LiCoO 2 ) showed a very stable charge-discharge behavior with a slight capacity loss under constant current and voltage conditions at the C/2-rate of 20 and 60 deg. C

  19. Sintering and microstructure evolution of columnar nickel-based superalloy sheets prepared by EB-PVD

    International Nuclear Information System (INIS)

    Chen, S.; Qu, S.J.; Liang, J.; Han, J.C.

    2010-01-01

    Research highlights: → EB-PVD technology is commonly used to deposit thermal barrier coatings (TBCs) and columnar structure is commonly seen in EB-PVD condensates. The unique columnar structure can provide outstanding resistance against thermal shock and mechanical strains for TBCs. However, a number of researchers have found that the columnar structure can affect the mechanical properties of EB-PVD alloy thin sheet significantly. As yet, works on how to reduce this kind of effects are seldom done. In the present article, we tried to reveal the sintering effects on microstructure evolution and mechanical properties of columnar Ni-based superalloy sheet. The results suggests that after sintering, the columnar structure degrades. Degradation depends on sintering temperature and time. Both the ultimate tensile strength and the elongation percentage are effectively improved after sintering. - Abstract: A ∼0.15 mm-thick columnar nickel-based superalloy sheet was obtained by electron beam physical vapor deposition (EB-PVD). The as-deposited alloy sheet was sintered at different conditions. The microstructure of the specimens before and after sintering was characterized by using scanning electron microscopy. An X'Pert texture facility was used to determine the crystallographic orientation of the as-deposited alloy sheet. The phase transformation was investigated by X-ray diffraction. Tensile tests were conducted at room temperature on as-deposited and sintered specimens. The results show that the as-deposited sheet is composed of typical columnar structures. After sintering, however, the columnar structure degrades. The degradation depends on sintering temperature and time. Both the ultimate tensile strength and the elongation percentage are effectively improved after sintering.

  20. PEGDA/PVdF/F127 gel type polymer electrolyte membranes for lithium secondary batteries

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Yan-Jie; Kim, Dukjoon [Department of Chemical Engineering, Polymer Technology Institute, Sungkyunkwan University, Suwon, Kyunggi 440-746 (Korea)

    2007-03-30

    A novel porous gel polymer electrolyte (GPE) membrane based on poly(ethylene glycol) diacrylate (PEGDA), poly(vinylidene fluoride) (PVdF), and polyethylene oxide-co-polypropylene oxide-co-polyethylene oxide (PEO-PPO-PEO, F127) was fabricated by a phase inversion technique. The PEGDA cross-linking oligomer could be randomly mixed with unraveled PVdF polymer chains to form the interpenetrating polymer network (IPN) structure. Several experimental techniques including infrared (IR) spectra, differential scanning calorimetry (DSC), thermogravimetric analyzer (TGA), scanning electron microscopy (SEM), electrochemical impedance spectroscopy (EIS) and potentiostat/galvanostat were employed to investigate the characteristics of the polymer membranes. PEGDA and F127 influenced the porous size and structure. The mechanical strength and flexibility of the membrane were controlled by its composition. The membrane with the composition of PEGDA/PVdF/F127 (0/4/4) showed the highest electrolyte uptake of 152.6% and the maximum ionic conductivity of 2.0 x 10{sup -3} S cm{sup -1} at room temperature. All GPEs prepared in this study were electrochemically stable up to 4.5 V. (author)

  1. Additional ion bombardment in PVD processes generated by a superimposed pulse bias voltage

    International Nuclear Information System (INIS)

    Olbrich, W.; Kampschulte, G.

    1993-01-01

    The superimposed pulse bias voltage is a tool to apply an additional ion bombardment during deposition in physical vapour deposition (PVD) processes. It is generated by the combination of a d.c. ground voltage and a higher d.c. pulse voltage. Using a superimposed pulse bias voltage in ion-assisted PVD processes effects an additional all-around ion bombardment on the surface with ions of higher energy. Both metal and reactive or inert-gas ions are accelerated to the surface. The basic principles and important characteristics of this newly developed process such as ion fluxes or deposition rates are shown. Because of pulsing the high voltage, the deposition temperature does not increase much. The adhesion, structure, morphology and internal stresses are influenced by these additional ion impacts. The columnar growth of the deposited films could be suppressed by using the superimposed pulse bias voltage without increasing the deposition temperature. Different metallizations (Cr and Cu) produced by arc and sputter ion plating are investigated. Carbon-fibre-reinforced epoxy are coated with PVD copper films for further treatment in electrochemical processes. (orig.)

  2. Controlling Dielectric and Magnetic Properties of PVdF/Magnetite Nanocomposite Fibre Webs

    Directory of Open Access Journals (Sweden)

    A. P. Venugopal

    2014-01-01

    Full Text Available The ability of filtration and separation media containing fibres to remove impurities from oil, water, and blood can be enhanced using magnetic fields. The ability to regulate the dielectric and magnetic behaviour of fibrous webs in terms of superparamagnetic or ferromagnetic properties by adjusting material composition is fundamental to meeting end-use requirements. Electrospun fibres were produced from PVdF (polyvinylidene fluoride and nanomagnetite (Fe3O4 nanoparticles from solutions of PVdF in dimethylacetamide containing Fe3O4 nanoparticle contents ranging from 3 to 10 wt%. Fibre dimensions, morphology, and nanoparticle agglomeration were characterised by environmental scanning electron microscopy (ESEM and field emission gun transmission electron microscopy (FEGTEM. Dielectric behaviour of the fibre webs was influenced by web porosity and the Fe3O4 nanoparticle content. Impedance analysis of the webs indicated an increase in dielectric constant of ∼80% by the addition of 10 wt% Fe3O4 nanoparticles compared to 100 wt% PVdF. The dielectric constants of the webs were compared with those obtained from the theoretical mixing models of Maxwell and Lichtenecker. Vibrating sample magnetometer (VSM magnetisation measurements indicated a blocking temperature above 300 K suggesting ferrimagnetic rather than superparamagnetic behaviour as a result of Fe3O4 nanoparticle agglomeration within fibres.

  3. Superhard PVD carbon films deposited with different gradients with and without additions of titanium and silicon

    International Nuclear Information System (INIS)

    Bauer, C.

    2003-10-01

    This work focusses on thin carbon-based films, deposited by magnetron sputtering with additional argon ion bombardment (0 eV to 800 eV) without extra adhesive layer on hard metal inserts. As one possibility of increasing the reduced adherence of hard carbon films the deposition of films with additions of titanium and silicon is studied. The aim of this work is to examine the influence of a modification of the transition between substrate and film by realizing three different types of deposition gradients. The pure carbon films are amorphous, the dominant network of atoms is formed by sp 2 bonded atoms. The amount of sp 3 bonded atoms is up to 30% and is influenced by the bombarding argon ion energy. Carbon films with additions of silicon are amorphous, only in films with a high amount of titanium (approx. 20 at%) nanocomposites of titanium carbide crystals with diameters of less than 5 nm in an amorphous carbon matrix were found. The mechanical properties and the behavior of single layer carbon films strongly depend on the argon ion energy. An increase of this energy leads to higher film hardness and higher residual stress and results in the delamination of superhard carbon films on hard metal substrates. The adhesion of single layer films for ion energies of more than 200 eV is significantly improved by additions of titanium and silicon, respectively. The addition of 23 at% silicon and titanium, respectively leads to a high reduction of the residual stress. In a non-reactive PVD process thin films were deposited with a continuously gradient in chemical composition. The results of the investigations of the films with two different concentrations of titanium and silicon, respectively show that carbon-based films with a good adhesion could be deposited. The combination of the two gradients in structure and properties and in chemical composition leads in the system with carbon and silicon carbide to hard and very adhesive films. Especially for carbon films with a high

  4. Hybrid diffusive/PVD treatments to improve the tribological resistance of Ti-6Al-4V.

    Science.gov (United States)

    Marin, E; Offoiach, R; Lanzutti, A; Regis, M; Fusi, S; Fedrizzi, L

    2014-01-01

    Titanium alloys are nowadays used for a wide range of biomedical applications thanks to their combination of high mechanical resistance, high corrosion resistance and biocompatibility. Nevertheless, the applicability of titanium alloys is sometimes limited due to their low microhardness and tribological resistance. Thus the titanium alloys cannot be successfully applied to prosthetic joint couplings. A wide range of surface treatments, in particular PVD coatings such as CrN and TiN, have been used in order to improve the tribological behaviour of titanium alloys. However, the low microhardness of the titanium substrate often results in coating failure due to cracks and delamination. For this reason, hybrid technologies based on diffusive treatments and subsequent PVD coatings may improve the overall coating resistance. In this work, conventional PVD coatings of CrN or TiCN, deposited on Titanium Grade 5, were characterized and then combined with a standard thermal diffusive nitriding treatment in order to improve the tribological resistance of the titanium alloys and avoid coating delamination. The different treatments were studied by means of scanning electron microscopy both on the sample surface and in cross-section. In-depth composition profiles were obtained using glow discharge optical emission spectrometry (GDOES) and localized energy dispersive X-ray diffraction on linear scan-lines. The microhardness and adhesion properties of the different treatments were evaluated using Vickers microhardness tests at different load conditions. The indentations were observed by means of SEM in order to evaluate delaminated areas and the crack's shape and density. The tribological behaviour of the different treatments was tested in dry conditions and in solution, in alternate pin-on-flat configuration, with a frequency of 0.5 Hz. After testing, the surface was investigated by means of stylus profilometry and SEM both on the surface and in cross-section. The standalone PVD

  5. Improving the Wear Resistance of Moulds for the Injection of Glass Fibre–Reinforced Plastics Using PVD Coatings: A Comparative Study

    Directory of Open Access Journals (Sweden)

    Francisco Silva

    2017-02-01

    Full Text Available It is well known that injection of glass fibre–reinforced plastics (GFRP causes abrasive wear in moulds’ cavities and runners. Physical vapour deposition (PVD coatings are intensively used to improve the wear resistance of different tools, also being one of the most promising ways to increase the moulds’ lifespan, mainly when used with plastics strongly reinforced with glass fibres. This work compares four different thin, hard coatings obtained using the PVD magnetron sputtering process: TiAlN, TiAlSiN, CrN/TiAlCrSiN and CrN/CrCN/DLC. The first two are monolayer coatings while the last ones are nanostructured and consist of multilayer systems. In order to carry out the corresponding tribological characterization, two different approaches were selected: A laboratorial method, using micro-abrasion wear tests based on a ball-cratering configuration, and an industrial mode, analysing the wear resistance of the coated samples when inserted in a plastic injection mould. As expected, the wear phenomena are not equivalent and the results between micro-abrasion and industrial tests are not similar due to the different means used to promote the abrasion. The best wear resistance performance in the laboratorial wear tests was attained by the TiAlN monolayer coating while the best performance in the industrial wear tests was obtained by the CrN/TiAlCrSiN nanostructured multilayer coating.

  6. corrosion and wear resistant ternary Cr-C-N coatings deposited by the ARC PVD process for machining tools and machining parts

    International Nuclear Information System (INIS)

    Knotek, O.; Lugscheider, E.; Zimmermann, H.; Bobzin, K.

    1997-01-01

    With the deposition of PVD hard coatings on the tools applied in machining operations it is possible to achieve significant improvements in the performance and quality of the machining processes. Depending on the machined material and the operating principle, e.g. turning, milling or drilling, not only different machining parameters but also different coating materials are necessary. In interrupted cut machining of tempered steel, for example, the life time of Ti-C-N coated inserts is several times greater than the Ti-C-N coated ones. This is a result of the favourable thermophysical and tribological properties of Ti-N-C. The potential for tool protection by CrN coatings is a result of the high ductility and low internal stress of this coating materials. CrN films can be deposited with greater film thickness, still maintaining very good adhesion. This paper presents the development of new arc PVD coatings in the system Cr-C-N. Owing to the carbon content in the coating an increased hardness and a better wear behavior in comparison to CrN was expected. The effects of various carbon carrier gases on the coating properties were examined. The coating properties were investigated by mechanical tests. X-ray diffraction, SEM analysis and corrosion tests. Some of the coatings were tested in machining tests. The results of these tests are presented in this paper. (author)

  7. Clinical use of Malay Version of Vertigo Symptom Scale (MWSS) in patients with peripheral vestibular disorder (PVD).

    Science.gov (United States)

    Zainun, Zuraida; Zakaria, Mohd Normani; Sidek, Dinsuhaimi; Ismail, Zalina

    2012-08-01

    The Vertigo symptom scale (VSS) is a well established tool for the evaluation of vestibular disorders and the associated symptoms of autonomic arousal and somatosensation. By using a validated Malay version of vertigo symptom scale (MVVSS) questionnaire, the severity of the vertigo from patients' perspective can be determined and rated. Before MVVSS can be applied clinically among Malaysians, it was of interest to determine its clinical value in identifying vestibular disorders. Forty normal and 65 PVD subjects participated in this cross-sectional study. Normal subjects were recruited amongst Universiti Sains Malaysia (USM) staff and students who had no history of ear and vestibular disorders. Mean total score of MVVSS in normal and PVD subjects were 13.9 +/- 11.1 and 30.1 +/- 20.9, respectively. When the total scores of normal and PVD group were compared, the Mann-Whitney U test showed that there was a significant difference between the two groups (p PVD [benign paroxymal positional vertigo (BPPV), Meniere's disease, labyrinthitis and unknown] have different MVVSS results. However, analysis of variance (ANOVA) found no significant difference in term of outcomes of MVVSS among the different PVD pathologies. Using receiver operating characteristic curve (ROC) method, the sensitivity and specificity of MVVSS were 71% and 60%, respectively. MVVSS is able to discriminate clinically among the normal and PVD subjects. However, it is not a good indicator for differential diagnosis of PVD subtypes, at least in this study. Its sensitivity and specificity in clinical diagnosis are reasonably high. Perhaps a bigger sample size would be useful to further study the clinical usefulness of MVVSS.

  8. Pain, psychological distress and motor pattern in women with provoked vestibulodynia (PVD) - symptom characteristics and therapy suggestions.

    Science.gov (United States)

    Haugstad, Gro Killi; Wojniusz, Slawomir; Kirste, Unni Merete; Kirschner, Rolf Steinar; Lilleheie, Ingvild; Haugstad, Tor Sigbjørn

    2018-04-25

    Provoked vestibulodynia (PVD) represent a longstanding pain syndrome that affects large numbers of women worldwide. However, no standardized guidelines for PVD treatment exist. In a cross-sectional pilot study we examined 30 PVD patients on multidimensional parameters including pain, psychological distress and quality of movement, in order to obtain a broader understanding of the somatic and psychological symptoms in PVD, and for the future to develop better interventions. Additionally, we compare the findings to previously published results regarding the same parameters in women with chronic pelvic pain (CPP). Thirty women with PVD recruited from a tertiary care university clinic of gynecology were assessed for demographic data, pain intensity (VAS), psychological distress (GHQ-30 and Tampa scale of Kinesophobia) and quality of movement (standardized Mensendieck test, SMT). Average age of the PVD women was 24.7±3.60 years, 60% of them were in permanent relationships, all were nulliparous, none had been subjected to surgical procedures, 100% were working full or part time and 90% were educated to at least undergraduate level. Mean VAS score was 7.77±1.97 (mean±SD), kinesiophobia 24.4±3.95 and anxiety domain of GHQ-30 9.73±4.06. SMT scores were particularly low for the domains of respiration and gait (less than 50% of optimal scores). PVD women display reduced quality of movement, especially for gait and respiration patterns, increased level of anxiety and high average pain scores. These findings are similar to what we have previously reported in CPP patients. However, in contrast to CPP group, PVD women are on average younger, have higher work participation, higher education level and have not been subjected to surgical procedures. Since PVD women display similar, although somewhat less severe, symptom profile than CPP, we suggest that a multidimensional approach to treatment, such as "somatocognitive therapy" should be investigated in this group as it has

  9. Protection of yttria-stabilized zirconia for dental applications by oxidic PVD coating.

    Science.gov (United States)

    Hübsch, C; Dellinger, P; Maier, H J; Stemme, F; Bruns, M; Stiesch, M; Borchers, L

    2015-01-01

    In this study, the application of transparent physical vapor deposition (PVD) coatings on zirconia ceramics was examined as an approach to retard the low-temperature degradation of zirconia for dental applications. Transparent monolayers of titanium oxide (TixOy) and multilayers consisting of titanium oxide-alumina-titanium oxide (TixOy-AlxOy-TixOy) were deposited onto standardized discs of 3Y-TZP using magnetron sputtering. Using X-ray photospectroscopy and time-of-flight secondary-ion mass spectrometry, the compositions of the coatings were verified, and an approximate thickness of 50 nm for each type of coating was ascertained. After aging the coated and uncoated samples in water vapor at 134°C and 3 bar for 4, 8, 16, 32, 64 and 128 h, the monoclinic phase content was determined using X-ray diffraction, and its impact on mechanical properties was assessed in biaxial flexural strength tests. In addition, the depth of the transformation zone was measured from scanning electron microscopy images of the fracture surfaces of hydrothermally aged samples. The results revealed that the tetragonal-to-monoclinic phase transformation of the zirconia ceramic was retarded by the application of PVD coatings. During the first stages of aging, the coated samples exhibited a significantly lower monoclinic phase content than the uncoated samples and, after 128 h of aging, showed a transformation zone which was only ∼12-15 μm thick compared to ∼30 μm in the control group. Biaxial flexural strength decreased by ∼10% during aging and was not influenced by the application of a PVD coating. Copyright © 2014 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

  10. NiCoCrAl/YSZ laminate composites fabricated by EB-PVD

    International Nuclear Information System (INIS)

    Shi Guodong; Wang Zhi; Liang Jun; Wu Zhanjun

    2011-01-01

    Highlights: → The metal-ceramic laminate composites were fabricated by EB-PVD. → Both metal and ceramic layers consisted of straight columns with banded structures. → Columnar grain size was limited by the periodic layer interfaces in the laminates. → Effect of columns on fracture property was decreased by limiting layer thickness. → Laminates showed greater specific strength than monolithic metal foil. - Abstract: Two NiCoCrAl/YSZ laminate composites (A and B) with different metal-layer thickness (∼35 μm and 14 μm, respectively) were fabricated by electron beam physical vapor deposition (EB-PVD). Their microstructure was examined and their mechanical properties were compared with the 289 μm thick NiCoCrAl monolithic foil produced by EB-PVD. Both the YSZ and NiCoCrAl layers of the laminate composites had columnar grain structure. But the periodic layer interfaces limited the columnar grain size. Some pores between the columns were also observed. It was found that the strength of the laminate A was equal approximately to that of the NiCoCrAl monolithic foil, and that laminate B had the greater strength. Moreover, the density of the foils decreased with the increasing thickness ratio of YSZ/NiCoCrAl layers and the increasing the layer number. Thus, comparing with the NiCoCrAl monolithic foil, the NiCoCrAl/YSZ laminate composites not only had the equal or greater strength, but also had the much greater specific strength.

  11. The properties of B-Sb thin films prepared by molecular flow region PVD process

    International Nuclear Information System (INIS)

    Kumashiro, Y.; Nakamura, K.; Sato, K.; Ohtsuka, M.; Ohishi, Y.; Nakano, M.; Doi, Y.

    2004-01-01

    The present paper is the first description on the electrical and thermoelectric properties of amorphous PVD B 12 Sb 2 films prepared using the reaction of decaborane gas with evaporated antimony gas on Si (1900 A) / SiO x (3700 A) / Si (100) (625 μm) substrate at the temperature 350 deg. C. Ohmic metals contacts of the film were examined by making evaporated Al, followed by annealing at 200 deg. C. The comparatively high mobility of ∼100 cm 2 /V s and high thermoelectric figures-of-merit of ∼10 -4 /K were confirmed

  12. Growth Mechanism for Low Temperature PVD Graphene Synthesis on Copper Using Amorphous Carbon

    Science.gov (United States)

    Narula, Udit; Tan, Cher Ming; Lai, Chao Sung

    2017-03-01

    Growth mechanism for synthesizing PVD based Graphene using Amorphous Carbon, catalyzed by Copper is investigated in this work. Different experiments with respect to Amorphous Carbon film thickness, annealing time and temperature are performed for the investigation. Copper film stress and its effect on hydrogen diffusion through the film grain boundaries are found to be the key factors for the growth mechanism, and supported by our Finite Element Modeling. Low temperature growth of Graphene is achieved and the proposed growth mechanism is found to remain valid at low temperatures.

  13. Structural characterisation of oxygen diffusion hardened alpha-tantalum PVD-coatings on titanium.

    Science.gov (United States)

    Hertl, C; Koll, L; Schmitz, T; Werner, E; Gbureck, U

    2014-08-01

    Titanium substrates were coated with tantalum layers of 5 μm thickness using physical vapour deposition (PVD). The tantalum layers showed a (110)-preferred orientation. The coated samples were hardened by oxygen diffusion. Using X-ray diffraction the crystallographic structure of the tantalum coatings was characterised, comparing untreated and diffusion hardened specimen conditions. Oxygen depth profiles were determined by glow discharge spectrometry. The hardening effect of the heat treatment was examined by Vickers microhardness testing. The increase of surface hardness caused by oxygen diffusion was at least 50%. Copyright © 2014 Elsevier B.V. All rights reserved.

  14. An apparatus for sequential pulsed plasma beam treatment in combination with Arc PVD deposition

    International Nuclear Information System (INIS)

    Stanislawski, J.; Werner, Z.; Piekoszewski, J.; Richter, E.

    2002-01-01

    A hybrid type of apparatus is described which enables one to form a thin multi-layer film on the surface of any kind of solid substrate. In one process, the surface is treated with a high intensity pulse plasma beam which introduces the chosen kind of atoms into the near-surface layer of the substrate. In the second process, following the first without breaking the vacuum, the coating is formed by arc PVD (physics vapour deposition) process. Two examples of coatings formed on metallic and ceramic substrates are presented. (author)

  15. Industrial PVD metallization for high efficiency crystalline silicon solar cells

    OpenAIRE

    Nekarda, J.; Reinwand, D.; Grohe, A.; Hartmann, P.; Preu, R.; Trassl, R.; Wieder, S.

    2009-01-01

    In this paper we present first results concerning different thermal evaporation processes for thin aluminum layers, which are carried out on a pilot system with a throughput of up to 540 wafers/h (156x156 mm2). To qualify the processes the deposited aluminum layers were evaluated with respect to homogeneity and conductivity. Additionally the effect of the different processes on the passivation quality of a thermally grown 100 nm thick SiO 2 was analyzed by means of lifetime measurements, indi...

  16. Frozen-in vacancies in PVD-Cu films with improved high-pressure reflowability studied using a slow positron beam

    Energy Technology Data Exchange (ETDEWEB)

    Yabuuchi, A; Kubo, D; Mizuno, M; Araki, H [Division of Materials and Manufacturing Science, Graduate School of Engineering, Osaka University, 2-1 Yamadaoka, Suita, Osaka 565-0871 (Japan); Onishi, T [Materials Research Laboratory, Kobe Steel Ltd., 5-5 Takatsukadai 1-chome, Nishi-ku, Kobe, Hyogo 651-2271 (Japan); Shirai, Y [Department of Materials Science and Engineering, Graduate School of Engineering, Kyoto University, Yoshida-Honmachi, Sakyo-ku, Kyoto 606-8501 (Japan)], E-mail: atsushi.yabuuchi@mat.eng.osaka-u.ac.jp

    2009-05-01

    Recently, a new process has been proposed for fabricating a LSI interconnection; filling trenches and via holes with Cu using high-pressure annealing treatment. It is already known that a Cu film produced by physical vapor deposition (PVD) has a lower reflowability compared to a Cu film produced by electrochemical deposition (ECD). Additionally, it has also been recognized that the addition of Sb to the PVD-Cu film improves the reflowability. However, the factors responsible for the reflowability of Cu films have not yet been studied. In this work, we evaluated a PVD pure-Cu film and a PVD Cu-0.5at%Sb film by using a slow positron beam. Addition of Sb led to the introduction of lattice defects in the as-deposited film. These defects that were observed in the PVD-CuSb dilute alloy film were identified as frozen-in vacancies that were produced during deposition.

  17. Frozen-in vacancies in PVD-Cu films with improved high-pressure reflowability studied using a slow positron beam

    International Nuclear Information System (INIS)

    Yabuuchi, A; Kubo, D; Mizuno, M; Araki, H; Onishi, T; Shirai, Y

    2009-01-01

    Recently, a new process has been proposed for fabricating a LSI interconnection; filling trenches and via holes with Cu using high-pressure annealing treatment. It is already known that a Cu film produced by physical vapor deposition (PVD) has a lower reflowability compared to a Cu film produced by electrochemical deposition (ECD). Additionally, it has also been recognized that the addition of Sb to the PVD-Cu film improves the reflowability. However, the factors responsible for the reflowability of Cu films have not yet been studied. In this work, we evaluated a PVD pure-Cu film and a PVD Cu-0.5at%Sb film by using a slow positron beam. Addition of Sb led to the introduction of lattice defects in the as-deposited film. These defects that were observed in the PVD-CuSb dilute alloy film were identified as frozen-in vacancies that were produced during deposition.

  18. The Role of SiO2 Gas in the Operation of Anti-Corrosion Coating Produced by PVD

    Directory of Open Access Journals (Sweden)

    Meysam Zarchi

    2015-09-01

    Full Text Available This study examined theSiO2 gas present in the coatings used in corrosion industry.These layers have been created by physical vapor deposition (PVD, with an appropriate performance. Sublimation of SiO2is used to protect PVD aluminum flakes from water corrosionand to generate highly porous SiO2 flakes with holes in the nanometer range. SiOx/Al/SiOx sandwiches were made as well as Ag loaded porous SiO2 as antimicrobial filler.

  19. A study on the high velocity impact behavior of titanium alloy by PVD method

    International Nuclear Information System (INIS)

    Sohn, Se Won; Lee, Doo Sung; Hong, Sung Hee

    2001-01-01

    In order to investigate the fracture behaviors(penetration modes) and resistance to penetration during ballistic impact of titanium alloy laminates and nitrified titanium alloy laminates which were treated by PVD(Physical Vapor Deposition) method, ballistic tests were conducted. Evaporation, sputtering, and ion plating are three kinds of PVD method. In this research, ion plating was used to achieve higher surface hardness and surface hardness test were conducted using a micro Vicker's hardness tester. Resistance to penetration is determined by the protection ballistic limit(V 50 ), a statistical velocity with 50% probability for complete penetration. Fracture behaviors and ballistic tolerance, described by penetration modes, are respectfully observed at and above ballistic limit velocities, as a result of V 50 test and Projectile Through Plates(PTP) test methods. PTP tests were conducted with 0 .deg. obliquity at room temperature using 5.56mm ball projectile. V 50 tests with 0 .deg. obliquity at room temperature were conducted with projectiles that were able to achieve near or complete penetration during PTP tests. Surface hardness, resistance to penetration, and penetration modes of titanium alloy laminates are compared to those of nitrified titanium alloy laminates

  20. Effects of synchrotron x-rays on PVD deposited and ion implanted α-Si

    International Nuclear Information System (INIS)

    Yu, K.M.; Wang, L.; Walukiewicz, W.; Muto, S.; McCormick, S.; Abelson, J.R.

    1997-01-01

    The authors have studied the effects of intense X-ray irradiation on the structure of amorphous Si films. The films were obtained by either physical vapor deposition or by implantation of high energy ions into crystalline Si. They were exposed to different total doses of synchrotron X-rays. From the EXAFS and EXELFS measurements they find that an exposure to X-rays increases the Si coordination number. Also in the PVD films a prolonged X-ray exposure enlarges, by about 2%, the Si-Si bond length. Raman spectroscopy shows that Si amorphized with high energy ions contains small residual amounts of crystalline material. Irradiation of such films with X-rays annihilates those crystallites resulting in homogeneously amorphous layer with a close to four-fold coordination of Si atoms. This rearrangement of the local structure has a pronounced effect on the crystallization process of the amorphous films. Thermal annealing of X-ray irradiated ion amorphized films leads to nearly defect free solid phase epitaxy at 500 C. Also they observe a delay in the onset of the crystallization process in X-ray irradiated PVD films. They associate this with a reduced concentration of nucleation centers in the x-ray treated materials

  1. Metallic Conductive Nanowires Elaborated by PVD Metal Deposition on Suspended DNA Bundles.

    Science.gov (United States)

    Brun, Christophe; Elchinger, Pierre-Henri; Nonglaton, Guillaume; Tidiane-Diagne, Cheikh; Tiron, Raluca; Thuaire, Aurélie; Gasparutto, Didier; Baillin, Xavier

    2017-09-01

    Metallic conductive nanowires (NWs) with DNA bundle core are achieved, thanks to an original process relying on double-stranded DNA alignment and physical vapor deposition (PVD) metallization steps involving a silicon substrate. First, bundles of DNA are suspended with a repeatable process between 2 µm high parallel electrodes with separating gaps ranging from 800 nm to 2 µm. The process consists in the drop deposition of a DNA lambda-phage solution on the electrodes followed by a naturally evaporation step. The deposition process is controlled by the DNA concentration within the buffer solution, the drop volume, and the electrode hydrophobicity. The suspended bundles are finally metallized with various thicknesses of titanium and gold by a PVD e-beam evaporation process. The achieved NWs have a width ranging from a few nanometers up to 100 nm. The electrical behavior of the achieved 60 and 80 nm width metallic NWs is shown to be Ohmic and their intrinsic resistance is estimated according to different geometrical models of the NW section area. For the 80 nm width NWs, a resistance of about few ohms is established, opening exploration fields for applications in microelectronics. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  2. Ion irradiation-induced stress relaxation in thin films and multilayers deposited using energetic PVD techniques

    International Nuclear Information System (INIS)

    Abadias, Gregory; Michel, Anny; Debelle, Aurelien; Jaouen, Christiane; Djemia Philippe

    2009-01-01

    The aim of the present work is to understand the stress build-up during energetic PVD film growth and the stress relaxation during subsequent ion irradiation at low dose (typically in the range 0.1-1.0 displacement per atom). Monolithic Mo thin films and Mo/Ni multilayers were grown using Dual Ion Beam Sputtering and Magnetron Sputtering at room temperature. Due to the high energy of incoming species (sputtered atoms, backscattered Ar), growth defects of interstitial-type are created during growth. The defect density can reach up to 1.4 % (far from equilibrium) in these Mo refractory layers. These defects act as misfitting particles, inducing a hydrostatic stress component and an associated in-plane compressive stress component. However, after Ar ion irradiation at low dose (∼0.2 dpa), most of the stress is relieved, showing that the growth induced defects are highly unstable. For Ni layers, the compressive stress is much lower due to the higher bulk atom mobility in this metal, making annihilation of defects more effective. An intermixing occurring mainly at the Mo/Ni interfaces is revealed from a complete strain-stress analysis using X-ray Diffraction. The magnitude of this interfacial alloying is found to increase with the energetics of the PVD process and is at the origin of the huge softening of the C 4 4 elastic constant, as measured using Brillouin light scattering. (authors)

  3. Structure and characteristics of EB-PVD thermal insulation layers; Struktur und Eigenschaften von EB-PVD-Waermedaemmschichten

    Energy Technology Data Exchange (ETDEWEB)

    Schulz, U. [Deutsche Forschungsanstalt fuer Luft- und Raumfahrt e.V. (DLR), Koeln (Germany). Inst. fuer Werkstoff-Forschung

    1996-12-31

    Thermal insulation layers for guide blades and rotor blades in the first two stages of a high-pressure turbines are produced by electron-beam physical vapour deposition for maximum quality. The layers have a lifetime that is longer by a factor of 2 to 10 than for plasma-sprayed layers. The following characteristics of the ceramic layer have a decisive influence on the life of the composite system: Phase composition, distribution and stability, microstructure, density, thickness, crack distribution and cohesive strength. Some selected aspects of the interdependence between production parameters, microstructure of the thermal insulation layer and service life are gone into. [Deutsch] Zur Herstellung von Waermedaemmschichten (WDS) fuer Turbinenleit- und Laufschaufeln der ersten beiden Stufen in der Hochdruckturbine wird fuer hoechste Ansprueche an die Schichtqualitaet das EB-PDV-Verfahren (electron-beam physical vapour deposition) eingesetzt. Die Lebensdauer dieser Schichten ist um den Faktor 2 bis 10 besser als beim Plasmaspritzen. Bei der keramischen Waermedaemmschicht selbst beeinflussen folgende Eigenschaften die Lebensdauer des Gesamtschichtsystems nachhaltig: Phasenzusammensetzung, -verteilung und -stabilitaet, Mikrogefuege, Dichte, Dicke, Rissverteilung und kohaesive Festigkeit. Auf einige ausgewaehlt Aspekte des Zusammenhangs zwischen Herstellungsparametern, Mikrostruktur der Waermedaemmschicht und Lebensdauer wird kurz eingegangen. (orig.)

  4. Stress analysis and microstructure of PVD monolayer TiN and multilayer TiN/(Ti,Al)N coatings

    NARCIS (Netherlands)

    Carvalho, NJM; Zoestbergen, E; Kooi, BJ; De Hosson, JTM

    2003-01-01

    Two PVD titanium nitride based coatings; monolayer TiN and multilayer resulting from the stacking of TiN and (Ti,Al)N layers were evaluated with respect to their stress state and microstructure. The TiN was deposited by triode evaporation ion plating, whereas the TiN/(Ti,AI)N was deposited using a

  5. Partial sulfonation of PVdF-co-HFP: A preliminary study and characterization for application in direct methanol fuel cell

    International Nuclear Information System (INIS)

    Das, Suparna; Kumar, Piyush; Dutta, Kingshuk; Kundu, Patit Paban

    2014-01-01

    Highlights: • Synthesis of sulfonated PVdF-co-HFP by reacting with chlorosulfonic acid. • Maximum degree of sulfonation and best properties were obtained for 7 h reaction. • A maximum water uptake value of 20% was obtained. • A maximum IEC value of 0.42 meq g −1 was obtained. • A methanol permeability of 2.44 × 10 −7 cm 2 s −1 was obtained. - Abstract: Sulfonation of PVdF-co-HFP was conducted by treating the copolymer with chlorosulfonic acid. The efficiency of this sulfonated copolymer towards application as a polymer electrolyte membrane in direct methanol fuel cell (DMFC) was evaluated. For this purpose, we determined the thermal stability, water uptake, ion exchange capacity (IEC), methanol crossover, and proton conductivity of the prepared membranes as functions of duration and degree of sulfonation. The characteristic aromatic peaks obtained in the FT-IR spectra confirmed the successful sulfonation of PVdF-co-HFP. The effect of sulfonation on the semi-crystalline nature of pure PVdF-co-HFP was determined from XRD analysis. Water uptake results indicated that a sulfonation time of 7 h produced maximum water uptake value of about 20%, with a corresponding IEC and proton conductivity values of about 0.42 meq g −1 and 0.00375 S cm −1 respectively. The maximum current density was recorded to be 30 mA cm −2 at 0.2 V potential

  6. [Efficacy of PVD regimen combined with IMRT for early-stage extranodal nasal NK/T-cell lymphoma].

    Science.gov (United States)

    Zhang, Y; Huang, Y H; Hu, Y F; Liu, Q L; Wu, T

    2017-07-11

    Objective: To evaluate the efficacy of PVD chemo-regimen (Pegaspargase, vincristine and dexamethasone) combined with intensity-modulated radiotherapy (IMRT) for patients with early-stage extranodal nasal NK/T-cell lymphoma (ENKL). Methods: Clinical data of 52 patients with early-stage ENKL were collected during May 2010 and June 2015 in Department of Lymphoma, Cancer Hospital of Guizhou Medical University, and these patients firstly received a concurrent chemoradiotherapy of two-cycle of PVD and IMRT (gross tumor volume primary: 12.6-59.4 Gy) and then 2 to 4 cycles of PVD as subsequent chemotherapy, the efficacy and adverse responses were retrospectively analyzed and observed. Results: Follow-up stopped until December 2015, complete remission was seen in 44 cases (84.6%) and partial remission 7 cases (13.5%), out of 52 cases. A total of 1 case died of progression disease during treatment and within 1 year after treatment, 1 case died of pulmonary infection within 1 week after treatment, 2 cases survived with tumor; so the objective response rate and clinical benefit rate were both 98.1%, 1-year, 2-year and 3-year overall survival rates and progression free survival rates were all 93.6%, 1-year and 2-year disease free survival rates were both 90.3%; the correlation analysis showed that the radiotherapy dose was related to the curative effect ( P PVD regimen and IMRT have a good therapeutic effect and adverse response can be tolerated.

  7. Mechanical properties of EB-PVD ZrO{sub 2} thermal barrier coatings; Mechanische Eigenschaften von EB-PVD ZrO{sub 2} Waermedaemmschichten

    Energy Technology Data Exchange (ETDEWEB)

    Held, Carolin

    2014-08-29

    In this work, the elastic properties of thermal barrier coatings which were produced by electron-beam enhanced physical vapour deposition were investigated, as well as the dependency of the properties on the sample microstructure, the thermal treatment and the test method. For this purpose, not only commercial coatings were characterized, but also special sample material was used which consists of a 1 mm thick layer of EB-PVD TBC. This material was isothermally heat treated for different times at 950 C, 1100 C and 1200 C and then tested in a specially developed miniaturized bend test and by dynamic mechanical analysis. The sample material was tested by nanoindentation in order to measure the Young's modulus on a local scale, and the porosity of the samples was determined by microstructure analysis and porosimetry. The decrease of porosity could be connected with sintering and subsequent stiffening of the material. The test results are dependent on the tested volume. A small test volume leads to larger measured Young's moduli, while a large test volume yields lower values. The test volume also has an influence on the increase of stiffness during thermal exposure. With a small tested volume, a quicker increase of the Young's modulus was registered, which could be associated to the sintering of local structures.

  8. Mechanical properties of EB-PVD ZrO{sub 2} thermal barrier coatings; Mechanische Eigenschaften von EB-PVD ZrO{sub 2} Waermedaemmschichten

    Energy Technology Data Exchange (ETDEWEB)

    Held, Carolin

    2014-08-29

    In this work, the elastic properties of thermal barrier coatings which were produced by electron-beam enhanced physical vapour deposition were investigated, as well as the dependency of the properties on the sample microstructure, the thermal treatment and the test method. For this purpose, not only commercial coatings were characterized, but also special sample material was used which consists of a 1 mm thick layer of EB-PVD TBC. This material was isothermally heat treated for different times at 950 C, 1100 C and 1200 C and then tested in a specially developed miniaturized bend test and by dynamic mechanical analysis. The sample material was tested by nanoindentation in order to measure the Young's modulus on a local scale, and the porosity of the samples was determined by microstructure analysis and porosimetry. The decrease of porosity could be connected with sintering and subsequent stiffening of the material. The test results are dependent on the tested volume. A small test volume leads to larger measured Young's moduli, while a large test volume yields lower values. The test volume also has an influence on the increase of stiffness during thermal exposure. With a small tested volume, a quicker increase of the Young's modulus was registered, which could be associated to the sintering of local structures.

  9. Prediction of the properties of PVD/CVD coatings with the use of FEM analysis

    International Nuclear Information System (INIS)

    Śliwa, Agata; Mikuła, Jarosław; Gołombek, Klaudiusz; Tański, Tomasz; Kwaśny, Waldemar; Bonek, Mirosław; Brytan, Zbigniew

    2016-01-01

    Highlights: • Prediction of the properties of PVD/CVD coatings with the use of (FEM) analysis. • Stress distribution in multilayer Ti/Ti(C,N)/CrN, Ti/Ti(C,N)/(Ti,Al)N coatings. • The experimental values of stresses were determined on X-ray diffraction patterns. • An FEM model was established for the purpose of building a computer simulation. - Abstract: The aim of this paper is to present the results of the prediction of the properties of PVD/CVD coatings with the use of finite element method (FEM) analysis. The possibility of employing the FEM in the evaluation of stress distribution in multilayer Ti/Ti(C,N)/CrN, Ti/Ti(C,N)/(Ti,Al)N, Ti/(Ti,Si)N/(Ti,Si)N, and Ti/DLC/DLC coatings by taking into account their deposition conditions on magnesium alloys has been discussed in the paper. The difference in internal stresses in the zone between the coating and the substrate is caused by, first of all, the difference between the mechanical and thermal properties of the substrate and the coating, and also by the structural changes that occur in these materials during the fabrication process, especially during the cooling process following PVD and CVD treatment. The experimental values of stresses were determined based on X-ray diffraction patterns that correspond to the modelled values, which in turn can be used to confirm the correctness of the accepted mathematical model for testing the problem. An FEM model was established for the purpose of building a computer simulation of the internal stresses in the coatings. The accuracy of the FEM model was verified by comparing the results of the computer simulation of the stresses with experimental results. A computer simulation of the stresses was carried out in the ANSYS environment using the FEM method. Structure observations, chemical composition measurements, and mechanical property characterisations of the investigated materials has been carried out to give a background for the discussion of the results that were

  10. Prediction of the properties of PVD/CVD coatings with the use of FEM analysis

    Energy Technology Data Exchange (ETDEWEB)

    Śliwa, Agata; Mikuła, Jarosław; Gołombek, Klaudiusz; Tański, Tomasz; Kwaśny, Waldemar; Bonek, Mirosław, E-mail: miroslaw.bonek@polsl.pl; Brytan, Zbigniew

    2016-12-01

    Highlights: • Prediction of the properties of PVD/CVD coatings with the use of (FEM) analysis. • Stress distribution in multilayer Ti/Ti(C,N)/CrN, Ti/Ti(C,N)/(Ti,Al)N coatings. • The experimental values of stresses were determined on X-ray diffraction patterns. • An FEM model was established for the purpose of building a computer simulation. - Abstract: The aim of this paper is to present the results of the prediction of the properties of PVD/CVD coatings with the use of finite element method (FEM) analysis. The possibility of employing the FEM in the evaluation of stress distribution in multilayer Ti/Ti(C,N)/CrN, Ti/Ti(C,N)/(Ti,Al)N, Ti/(Ti,Si)N/(Ti,Si)N, and Ti/DLC/DLC coatings by taking into account their deposition conditions on magnesium alloys has been discussed in the paper. The difference in internal stresses in the zone between the coating and the substrate is caused by, first of all, the difference between the mechanical and thermal properties of the substrate and the coating, and also by the structural changes that occur in these materials during the fabrication process, especially during the cooling process following PVD and CVD treatment. The experimental values of stresses were determined based on X-ray diffraction patterns that correspond to the modelled values, which in turn can be used to confirm the correctness of the accepted mathematical model for testing the problem. An FEM model was established for the purpose of building a computer simulation of the internal stresses in the coatings. The accuracy of the FEM model was verified by comparing the results of the computer simulation of the stresses with experimental results. A computer simulation of the stresses was carried out in the ANSYS environment using the FEM method. Structure observations, chemical composition measurements, and mechanical property characterisations of the investigated materials has been carried out to give a background for the discussion of the results that were

  11. Woman and partner-perceived partner responses predict pain and sexual satisfaction in provoked vestibulodynia (PVD) couples.

    Science.gov (United States)

    Rosen, Natalie O; Bergeron, Sophie; Leclerc, Bianca; Lambert, Bernard; Steben, Marc

    2010-11-01

    Provoked vestibulodynia (PVD) is a highly prevalent vulvovaginal pain condition that results in significant sexual dysfunction, psychological distress, and reduced quality of life. Although some intra-individual psychological factors have been associated with PVD, studies to date have neglected the interpersonal context of this condition. We examined whether partner responses to women's pain experience-from the perspective of both the woman and her partner-are associated with pain intensity, sexual function, and sexual satisfaction. One hundred ninety-one couples (M age for women=33.28, standard deviation [SD]=12.07, M age for men=35.79, SD=12.44) in which the woman suffered from PVD completed the spouse response scale of the Multidimensional Pain Inventory, assessing perceptions of partners' responses to the pain. Women with PVD also completed measures of pain, sexual function, sexual satisfaction, depression, and dyadic adjustment. Dependent measures were women's responses to: (i) a horizontal analog scale assessing the intensity of their pain during intercourse; (ii) the Female Sexual Function Index; and (iii) the Global Measure of Sexual Satisfaction Scale. Controlling for depression, higher solicitous partner responses were associated with higher levels of women's vulvovaginal pain intensity. This association was significant for partner-perceived responses (β=0.29, Psexual function and dyadic adjustment, woman-perceived greater solicitous partner responses (β=0.16, P=0.02) predicted greater sexual satisfaction. Partner-perceived responses did not predict women's sexual satisfaction. Partner responses were not associated with women's sexual function. Findings support the integration of dyadic processes in the conceptualization and treatment of PVD by suggesting that partner responses to pain affect pain intensity and sexual satisfaction in affected women. © 2010 International Society for Sexual Medicine.

  12. Effect of PbI2 deposition rate on two-step PVD/CVD all-vacuum prepared perovskite

    International Nuclear Information System (INIS)

    Ioakeimidis, Apostolos; Christodoulou, Christos; Lux-Steiner, Martha; Fostiropoulos, Konstantinos

    2016-01-01

    In this work we fabricate all-vacuum processed methyl ammonium lead halide perovskite by a sequence of physical vapour deposition of PbI 2 and chemical vapour deposition (CVD) of CH 3 NH 3 I under a static atmosphere. We demonstrate that for higher deposition rate the (001) planes of PbI 2 film show a higher degree of alignment parallel to the sample's surface. From X-ray diffraction data of the resulted perovskite film we derive that the intercalation rate of CH 3 NH 3 I is fostered for PbI 2 films with higher degree of (001) planes alignment. The stoichiometry of the produced perovskite film is also studied by Hard X-ray photoelectron spectroscopy measurements. Complete all-vacuum perovskite solar cells were fabricated on glass/ITO substrates coated by an ultra-thin (5 nm) Zn-phthalocyanine film as hole selective layer. A dependence of residual PbI 2 on the solar cells performance is displayed, while photovoltaic devices with efficiency up to η=11.6% were achieved. - Graphical abstract: A two-step PVD/CVD processed perovskite film with the CVD intercalation rate of CH 3 NCH 3 molecules been fostered by increasing the PVD rate of PbI 2 and prolonging the CVD time. - Highlights: • A simple PVD/CVD process for perovskite film production. • Increased PVD rate yields better alignment of the PbI 2 (001) crystallite planes. • CH 3 NH 3 I intercalation process fostered by increased PbI 2 PVD rate. • Stoichiometric CH 3 NH 3 PbI 3 suitable as absorber in photovoltaic applications • Reduced PbI 2 residue at the bottom of CH 3 NH 3 PbI 3 improves device performance.

  13. Non-classical crystallization of thin films and nanostructures in CVD and PVD processes

    CERN Document Server

    Hwang, Nong Moon

    2016-01-01

    This book provides a comprehensive introduction to a recently-developed approach to the growth mechanism of thin films and nanostructures via chemical vapour deposition (CVD). Starting from the underlying principles of the low pressure synthesis of diamond films, it is shown that diamond growth occurs not by individual atoms but by charged nanoparticles. This newly-discovered growth mechanism turns out to be general to many CVD and some physical vapor deposition (PVD) processes. This non-classical crystallization is a new paradigm of crystal growth, with active research taking place on growth in solution, especially in biomineralization processes. Established understanding of the growth of thin films and nanostructures is based around processes involving individual atoms or molecules. According to the author’s research over the last two decades, however, the generation of charged gas phase nuclei is shown to be the rule rather than the exception in the CVD process, and charged gas phase nuclei are actively ...

  14. Characterization and evaluation of EB-PVD thermal barrier coatings by impedance spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Zhang Chunxia; Liu Fushun; Gong Shengkai; Xu Huibin [School of Materials Science and Engineering, Beihang Univ., Beijing, BJ (China)

    2005-07-01

    Two layer thermal barrier coatings (TBCs) were prepared by EB-PVD (electron beam-physical vapor deposition) at different substrate temperatures in the range of 823 to 1123 K, and their microstructure was investigated with SEM and AC impedance as a function of substrate temperature and thermal cycling time. YSZ layer of all TBCs samples is in column structure, but the grain size and growth orientation are different with substrate. In this research, impedance spectra (IS) was measured as a function of thermal cycling between 1323 K and 298 K for these thermal barrier coatings. Grain boundary and bulk can be distinguished from analysis of AC impedance spectroa to provide information about the relation between microstructure and electric properties. The change in IS until failure was found to be related with the thickness, microcracks and macrocracks of TGO and the change in the interfacial of TGO/YSZ. (orig.)

  15. Double Pulse LIBS of Titanium-Based PVD-Coatings with Submicron Resolution

    Directory of Open Access Journals (Sweden)

    K. Ermalitskaia

    2016-01-01

    Full Text Available The possibility for double pulse LIBS in the process of a direct layer-by-layer analysis of the titanium-based PVD-coatings on polished flat blank samples of steel and silicon and also of the TiAlN/TiN-coating on a milling cutter is considered. A method is proposed to control thickness of the radiation evaporated layer by defocusing the laser beam with respect to the surface, making it possible to attain the depth resolution of 0.1 μm. The Ti and Ti-Zr-coatings produced using the ion-assisted condensation method and subjected to streams of the nitrogen plasma in a magnetic-plasma compressor are studied.

  16. Investigations on PVdF- HFP - PEMA polymer blend electrolytes doped with different lithium salts

    Science.gov (United States)

    Manojkumar Ubarhande, Radha; Bhattacharya, Shreya; Usha Rani, M.; Shanker Babu, Ravi; Krishnaveni, S.

    2017-11-01

    Plasticized polymer blend electrolytes were prepared by incorporating poly (vinylidenefluoride-co-hexafluoropropylene)(PVdF-HFP) and poly(ethylmethacrylate) (PEMA) complexed with plasticizer (PC) and different lithium salts such as LiClO4, LiBF4, LiCF3SO3 and LiN (CF3SO2)2) using solution-casting technique. X-ray diffraction and Fourier transform infra-red techniques confirms the structural characters and complex formation of the polymer electrolytes respectively. AC impedance analysis was carried out for all the samples in the range303-373K. The results suggest that among the various lithium salts, LiN (CF3SO2)2) based electrolytes exhibited the highest ionic conductivity (3.17 × 10-3 Scm-1).

  17. Synthesis and electrochemical properties of composite galvanic Ni with carbon nanomaterials and PVD Mo coatings

    International Nuclear Information System (INIS)

    Drozdovich, V.B.; Chayeuski, V.V.; Zhdanok, S.A.; Barkovskaya, M.M.

    2011-01-01

    Double layer coatings Ni – Mo were obtained by electrolytic deposition of galvanic Ni and following arc PVD deposition of molybdenum. The ion plating coatings Mo on Ni foil and composition electrolytic Ni coatings with carbon nanomaterials (CNM) deposited on mild steel has been also investigated. Composite galvanic Ni coatings with CNM and ion plating coatings Mo contain separately obtained cubic α-Mo phase as well as fragmentary solid solution Mo in Ni. Such coatings exclude hydrogenation of Ni foundation in alkaline solution and possess enlarged electrocatalytic properties while emitting hydrogen and oxygen. Availability of carbon based nanomaterials in combined coatings is cause of an active absorption hydrogen after cathodic polarization. A formation on the surface layer of nanostructure solid solution (Ni, Mo) after compression plasma flows treatment with fixed parameters of patterns Mo/Ni/ mild steel take place. (authors)

  18. Structure and functionality of PVdF/PAN based, composite proton conducting membranes

    International Nuclear Information System (INIS)

    Martinelli, A.; Navarra, M.A.; Matic, A.; Panero, S.; Jacobsson, P.; Boerjesson, L.; Scrosati, B.

    2005-01-01

    We have investigated new poly-vinylidene fluoride/poly-acrylonitrile (PVdF/PAN) based proton conducting membranes by means of vibrational spectroscopy. We find that a complete phase inversion occurs during the preparation procedure, when the gelling solvents are replaced by an acidic solution, providing the proton conducting property. The uptake of acid is promoted both by the presence of PAN and the ceramic filler, Al 2 O 3 . No particular interaction between the polymer matrix and the acidic solution could be detected, supporting the picture of an inert matrix entrapping a liquid component. However, the dissociation degree of the acid is decreased due to the spatial confinement in the membrane. By comparing the dissociation degree and the actual amount of acid in the membrane to the conductivity, we conclude that the limiting factor for the conductivity is the long-range mobility of the protons, which is governed by the morphology of the membrane

  19. Investigation of the Effect of Residual Stress Gradient on the Wear Behavior of PVD Thin Films

    Science.gov (United States)

    Tlili, B.; Nouveau, C.; Guillemot, G.; Besnard, A.; Barkaoui, A.

    2018-02-01

    The control of residual stresses has been seldom investigated in multilayer coatings dedicated to improvement of wear behavior. Here, we report the preparation and characterization of superposed structures composed of Cr, CrN and CrAlN layers. Nano-multilayers CrN/CrAlN and Cr/CrN/CrAlN were deposited by Physical Vapor Deposition (PVD) onto Si (100) and AISI4140 steel substrates. The Cr, CrN and CrAlN monolayers were developed with an innovative approach in PVD coatings technologies corresponding to deposition with different residual stresses levels. Composition and wear tracks morphologies of the coatings were characterized by scanning electron microscopy, high-resolution transmission electron microscopy, atomic force microscopy, x-ray photoelectron spectroscopy, energy-dispersive x-ray spectroscopy, x-ray diffraction and 3D-surface analyzer. The mechanical properties (hardness, residual stresses and wear) were investigated by nanoindentation, interferometry and micro-tribometry (fretting-wear tests). Observations suggest that multilayer coatings are composed mostly of nanocrystalline. The residual stresses level in the films has practically affected all the physicochemical and mechanical properties as well as the wear behavior. Consequently, it is demonstrated that the coating containing moderate stresses has a better wear behavior compared to the coating developed with higher residual stresses. The friction contact between coated samples and alumina balls shows also a large variety of wear mechanisms. In particular, the abrasive wear of the coatings was a combination of plastic deformation, fine microcracking and microspallation. The application of these multilayers will be wood machining of green wood.

  20. Injection moulding of optical functional micro structures using laser structured, PVD-coated mould inserts

    Energy Technology Data Exchange (ETDEWEB)

    Hopmann, Ch.; Weber, M.; Schöngart, M.; Schäfer, C., E-mail: weber@ikv-aachen.de [Institute of Plastics Processing (IKV) at RWTH Aachen University (Germany); Bobzin, K.; Bagcivan, N.; Brögelmann, T.; Theiß, S.; Münstermann, T. [Surface Engineering Institute (IOT), RWTH Aachen University, Aachen (Germany); Steger, M. [Fraunhofer Institute for Laser Technology (ILT), Aachen (Germany)

    2015-05-22

    Micro structured optical plastics components are intensively used i. e. in consumer electronics, for optical sensors in metrology, innovative LED-lighting or laser technology. Injection moulding has proven to be successful for the large-scale production of those parts. However, the production of those parts still causes difficulties due to challenges in the moulding and demoulding of plastics parts created with laser structured mould inserts. A complete moulding of the structures often leads to increased demoulding forces, which then cause a breaking of the structures and a clogging of the mould. An innovative approach is to combine PVD-coated (physical vapour deposition), laser structured inserts and a variothermal moulding process to create functional mic8iüro structures in a one-step process. Therefore, a PVD-coating is applied after the laser structuring process in order to improve the wear resistance and the anti-adhesive properties against the plastics melt. In a series of moulding trials with polycarbonate (PC) and polymethylmethacrylate (PMMA) using different coated moulds, the mould temperature during injection was varied in the range of the glass transition and the melt temperature of the polymers. Subsequently, the surface topography of the moulded parts is evaluated by digital 3D laser-scanning microscopy. The influence of the moulding parameters and the coating of the mould insert on the moulding accuracy and the demoulding behaviour are being analysed. It is shown that micro structures created by ultra-short pulse laser ablation can be successfully replicated in a variothermal moulding process. Due to the mould coating, significant improvements could be achieved in producing micro structured optical plastics components.

  1. Prediction of the properties of PVD/CVD coatings with the use of FEM analysis

    Science.gov (United States)

    Śliwa, Agata; Mikuła, Jarosław; Gołombek, Klaudiusz; Tański, Tomasz; Kwaśny, Waldemar; Bonek, Mirosław; Brytan, Zbigniew

    2016-12-01

    The aim of this paper is to present the results of the prediction of the properties of PVD/CVD coatings with the use of finite element method (FEM) analysis. The possibility of employing the FEM in the evaluation of stress distribution in multilayer Ti/Ti(C,N)/CrN, Ti/Ti(C,N)/(Ti,Al)N, Ti/(Ti,Si)N/(Ti,Si)N, and Ti/DLC/DLC coatings by taking into account their deposition conditions on magnesium alloys has been discussed in the paper. The difference in internal stresses in the zone between the coating and the substrate is caused by, first of all, the difference between the mechanical and thermal properties of the substrate and the coating, and also by the structural changes that occur in these materials during the fabrication process, especially during the cooling process following PVD and CVD treatment. The experimental values of stresses were determined based on X-ray diffraction patterns that correspond to the modelled values, which in turn can be used to confirm the correctness of the accepted mathematical model for testing the problem. An FEM model was established for the purpose of building a computer simulation of the internal stresses in the coatings. The accuracy of the FEM model was verified by comparing the results of the computer simulation of the stresses with experimental results. A computer simulation of the stresses was carried out in the ANSYS environment using the FEM method. Structure observations, chemical composition measurements, and mechanical property characterisations of the investigated materials has been carried out to give a background for the discussion of the results that were recorded during the modelling process.

  2. Tribological and Wear Performance of Nanocomposite PVD Hard Coatings Deposited on Aluminum Die Casting Tool

    Directory of Open Access Journals (Sweden)

    Jose Mario Paiva

    2018-02-01

    Full Text Available In the aluminum die casting process, erosion, corrosion, soldering, and die sticking have a significant influence on tool life and product quality. A number of coatings such as TiN, CrN, and (Cr,AlN deposited by physical vapor deposition (PVD have been employed to act as protective coatings due to their high hardness and chemical stability. In this study, the wear performance of two nanocomposite AlTiN and AlCrN coatings with different structures were evaluated. These coatings were deposited on aluminum die casting mold tool substrates (AISI H13 hot work steel by PVD using pulsed cathodic arc evaporation, equipped with three lateral arc-rotating cathodes (LARC and one central rotating cathode (CERC. The research was performed in two stages: in the first stage, the outlined coatings were characterized regarding their chemical composition, morphology, and structure using glow discharge optical emission spectroscopy (GDOES, scanning electron microscopy (SEM, and X-ray diffraction (XRD, respectively. Surface morphology and mechanical properties were evaluated by atomic force microscopy (AFM and nanoindentation. The coating adhesion was studied using Mersedes test and scratch testing. During the second stage, industrial tests were carried out for coated die casting molds. In parallel, tribological tests were also performed in order to determine if a correlation between laboratory and industrial tests can be drawn. All of the results were compared with a benchmark monolayer AlCrN coating. The data obtained show that the best performance was achieved for the AlCrN/Si3N4 nanocomposite coating that displays an optimum combination of hardness, adhesion, soldering behavior, oxidation resistance, and stress state. These characteristics are essential for improving the die mold service life. Therefore, this coating emerges as a novelty to be used to protect aluminum die casting molds.

  3. Tribological and Wear Performance of Nanocomposite PVD Hard Coatings Deposited on Aluminum Die Casting Tool.

    Science.gov (United States)

    Paiva, Jose Mario; Fox-Rabinovich, German; Locks Junior, Edinei; Stolf, Pietro; Seid Ahmed, Yassmin; Matos Martins, Marcelo; Bork, Carlos; Veldhuis, Stephen

    2018-02-28

    In the aluminum die casting process, erosion, corrosion, soldering, and die sticking have a significant influence on tool life and product quality. A number of coatings such as TiN, CrN, and (Cr,Al)N deposited by physical vapor deposition (PVD) have been employed to act as protective coatings due to their high hardness and chemical stability. In this study, the wear performance of two nanocomposite AlTiN and AlCrN coatings with different structures were evaluated. These coatings were deposited on aluminum die casting mold tool substrates (AISI H13 hot work steel) by PVD using pulsed cathodic arc evaporation, equipped with three lateral arc-rotating cathodes (LARC) and one central rotating cathode (CERC). The research was performed in two stages: in the first stage, the outlined coatings were characterized regarding their chemical composition, morphology, and structure using glow discharge optical emission spectroscopy (GDOES), scanning electron microscopy (SEM), and X-ray diffraction (XRD), respectively. Surface morphology and mechanical properties were evaluated by atomic force microscopy (AFM) and nanoindentation. The coating adhesion was studied using Mersedes test and scratch testing. During the second stage, industrial tests were carried out for coated die casting molds. In parallel, tribological tests were also performed in order to determine if a correlation between laboratory and industrial tests can be drawn. All of the results were compared with a benchmark monolayer AlCrN coating. The data obtained show that the best performance was achieved for the AlCrN/Si₃N₄ nanocomposite coating that displays an optimum combination of hardness, adhesion, soldering behavior, oxidation resistance, and stress state. These characteristics are essential for improving the die mold service life. Therefore, this coating emerges as a novelty to be used to protect aluminum die casting molds.

  4. Effect of Hexagonal Phase Content on Wear Behaviour of AlTiN Arc PVD Coatings

    Directory of Open Access Journals (Sweden)

    Joern Kohlscheen

    2018-02-01

    Full Text Available In this study, the effect of increasing aluminum content and magnetic steering field strength on the structure and wear behavior of arc PVD AlTiN coatings is discussed. Deposition was done by means of an industrial-scale PVD unit for tool coating. The aluminium content in the AlTi source material was increased from 67 to 73 at.%. We applied two settings of the magnetic field that steers the arc across the cathode surface thereby evaporating the AlTi alloy differently. The resulting coating thickness ranged from 3.5 to about 7 µm. Cemented tungsten carbide was used as substrate material. Coating properties like hardness, adhesion, and crystal phases were analyzed by indentation and X-ray diffraction, respectively. The wear behaviour of the different AlTiN hard coatings were investigated in two ways. In a first idealized test, cyclic impacting was done applying a constant force. The resulting wear pattern was quantified by an Alicona multi-focus microscope. A second wear test was done by metal cutting under realistic conditions. Fly milling of ductile cast iron (EN-GJS-700 was performed with regular interruptions in order to measure the increasing wear mark. As expected, aluminium contents above 67 at.% (in the metal fraction of the coating lead to a decreased wear resistance as the soft hexagonal phase exceeds values of a few vol.%. However, it was found that the formation of the hexagonal phase can be effectively influenced and delayed by increasing the magnetic steering field at the cathode. The wear behavior observed in cyclic impact testing corresponds well to results obtained with the more complex loading situation encountered in milling.

  5. Hierarchical adaptive nanostructured PVD coatings for extreme tribological applications: the quest for nonequilibrium states and emergent behavior

    Directory of Open Access Journals (Sweden)

    German S Fox-Rabinovich, Kenji Yamamoto, Ben D Beake, Iosif S Gershman, Anatoly I Kovalev, Stephen C Veldhuis, Myram H Aguirre, Goulnara Dosbaeva and Jose L Endrino

    2012-01-01

    Full Text Available Adaptive wear-resistant coatings produced by physical vapor deposition (PVD are a relatively new generation of coatings which are attracting attention in the development of nanostructured materials for extreme tribological applications. An excellent example of such extreme operating conditions is high performance machining of hard-to-cut materials. The adaptive characteristics of such coatings develop fully during interaction with the severe environment. Modern adaptive coatings could be regarded as hierarchical surface-engineered nanostructural materials. They exhibit dynamic hierarchy on two major structural scales: (a nanoscale surface layers of protective tribofilms generated during friction and (b an underlying nano/microscaled layer. The tribofilms are responsible for some critical nanoscale effects that strongly impact the wear resistance of adaptive coatings. A new direction in nanomaterial research is discussed: compositional and microstructural optimization of the dynamically regenerating nanoscaled tribofilms on the surface of the adaptive coatings during friction. In this review we demonstrate the correlation between the microstructure, physical, chemical and micromechanical properties of hard coatings in their dynamic interaction (adaptation with environment and the involvement of complex natural processes associated with self-organization during friction. Major physical, chemical and mechanical characteristics of the adaptive coating, which play a significant role in its operating properties, such as enhanced mass transfer, and the ability of the layer to provide dissipation and accumulation of frictional energy during operation are presented as well. Strategies for adaptive nanostructural coating design that enhance beneficial natural processes are outlined. The coatings exhibit emergent behavior during operation when their improved features work as a whole. In this way, as higher-ordered systems, they achieve multifunctionality

  6. Hierarchical adaptive nanostructured PVD coatings for extreme tribological applications: the quest for nonequilibrium states and emergent behavior.

    Science.gov (United States)

    Fox-Rabinovich, German S; Yamamoto, Kenji; Beake, Ben D; Gershman, Iosif S; Kovalev, Anatoly I; Veldhuis, Stephen C; Aguirre, Myriam H; Dosbaeva, Goulnara; Endrino, Jose L

    2012-08-01

    Adaptive wear-resistant coatings produced by physical vapor deposition (PVD) are a relatively new generation of coatings which are attracting attention in the development of nanostructured materials for extreme tribological applications. An excellent example of such extreme operating conditions is high performance machining of hard-to-cut materials. The adaptive characteristics of such coatings develop fully during interaction with the severe environment. Modern adaptive coatings could be regarded as hierarchical surface-engineered nanostructural materials. They exhibit dynamic hierarchy on two major structural scales: (a) nanoscale surface layers of protective tribofilms generated during friction and (b) an underlying nano/microscaled layer. The tribofilms are responsible for some critical nanoscale effects that strongly impact the wear resistance of adaptive coatings. A new direction in nanomaterial research is discussed: compositional and microstructural optimization of the dynamically regenerating nanoscaled tribofilms on the surface of the adaptive coatings during friction. In this review we demonstrate the correlation between the microstructure, physical, chemical and micromechanical properties of hard coatings in their dynamic interaction (adaptation) with environment and the involvement of complex natural processes associated with self-organization during friction. Major physical, chemical and mechanical characteristics of the adaptive coating, which play a significant role in its operating properties, such as enhanced mass transfer, and the ability of the layer to provide dissipation and accumulation of frictional energy during operation are presented as well. Strategies for adaptive nanostructural coating design that enhance beneficial natural processes are outlined. The coatings exhibit emergent behavior during operation when their improved features work as a whole. In this way, as higher-ordered systems, they achieve multifunctionality and high wear

  7. Prefabricated Vertical Drain (PVD) and Deep Cement Mixing (DCM)/Stiffened DCM (SDCM) techniques for soft ground improvement

    Science.gov (United States)

    Bergado, D. T.; Long, P. V.; Chaiyaput, S.; Balasubramaniam, A. S.

    2018-04-01

    Soft ground improvement techniques have become most practical and popular methods to increase soil strength, soil stiffness and reduce soil compressibility including the soft Bangkok clay. This paper focuses on comparative performances of prefabricated vertical drain (PVD) using surcharge, vacuum and heat preloading as well as the cement-admixed clay of Deep Cement Mixing (DCM) and Stiffened DCM (SDCM) methods. The Vacuum-PVD can increase the horizontal coefficient of consolidation, Ch, resulting in faster rate of settlement at the same magnitudes of settlement compared to Conventional PVD. Several field methods of applying vacuum preloading are also compared. Moreover, the Thermal PVD and Thermal Vacuum PVD can increase further the coefficient of horizontal consolidation, Ch, with the associated reduction of kh/ks values by reducing the drainage retardation effects in the smear zone around the PVD which resulted in faster rates of consolidation and higher magnitudes of settlements. Furthermore, the equivalent smear effect due to non-uniform consolidation is also discussed in addition to the smear due to the mechanical installation of PVDs. In addition, a new kind of reinforced deep mixing method, namely Stiffened Deep Cement Mixing (SDCM) pile is introduced to improve the flexural resistance, improve the field quality control, and prevent unexpected failures of the Deep Cement Mixing (DCM) pile. The SDCM pile consists of DCM pile reinforced with the insertion of precast reinforced concrete (RC) core. The full scale test embankment on soft clay improved by SDCM and DCM piles was also analysed. Numerical simulations using the 3D PLAXIS Foundation finite element software have been done to understand the behavior of SDCM and DCM piles. The simulation results indicated that the surface settlements decreased with increasing lengths of the RC cores, and, at lesser extent, increasing sectional areas of the RC cores in the SDCM piles. In addition, the lateral movements

  8. Advanced neutron and X-ray techniques for insights into the microstructure of EB-PVD thermal barrier coatings

    Energy Technology Data Exchange (ETDEWEB)

    Kulkarni, Anand [State University of New York, Stony Brook, NY 11794 (United States); Goland, Allen [State University of New York, Stony Brook, NY 11794 (United States); Herman, Herbert [State University of New York, Stony Brook, NY 11794 (United States)]. E-mail: hherman@ms.cc.sunysb.edu; Allen, Andrew J. [National Institute of Standards and Technology, Gaithersburg, MD 20899 (United States); Dobbins, Tabbetha [National Institute of Standards and Technology, Gaithersburg, MD 20899 (United States); DeCarlo, Francesco [Argonne National Laboratory, Argonne, IL 60439 (United States); Ilavsky, Jan [Argonne National Laboratory, Argonne, IL 60439 (United States); Long, Gabrielle G. [Argonne National Laboratory, Argonne, IL 60439 (United States); Fang, Stacy [Chromalloy Gas Turbine Corporation, Orangeburg, NY 10962 (United States); Lawton, Paul [Chromalloy Gas Turbine Corporation, Orangeburg, NY 10962 (United States)

    2006-06-25

    The ongoing quest to increase gas turbine efficiency and performance (increased thrust) provides a driving force for materials development. While improved engine design and usage of novel materials provide solutions for increased engine operating temperatures, and hence fuel efficiency, reliability issues remain. Thermal barrier coatings (TBCs), deposited onto turbine components using the electron-beam physical vapor deposition (EB-PVD) process, exhibit unique pore architectures capable of bridging the technological gap between insulation/life extension and prime reliance. This article explores the potential of advanced X-ray and neutron techniques for comprehension of an EB-PVD TBC coating microstructure. While conventional microscopy reveals a hierarchy of voids, complementary advanced techniques allow quantification of these voids in terms of component porosities, anisotropy, size and gradient through the coating thickness. In addition, the derived microstructural parameters obtained both further knowledge of the nature and architecture of the porosity, and help establish its influence on the resultant thermal and mechanical properties.

  9. PVD Silicon Carbide as a Thin Film Packaging Technology for Antennas on LCP Substrates for Harsh Environments

    Science.gov (United States)

    Scardelletti, Maximilian C.; Stanton, John W.; Ponchak, George E.; Jordan, Jennifer L.; Zorman, Christian A.

    2010-01-01

    This paper describes an effort to develop a thin film packaging technology for microfabricated planar antennas on polymeric substrates based on silicon carbide (SiC) films deposited by physical vapor deposition (PVD). The antennas are coplanar waveguide fed dual frequency folded slot antennas fabricated on liquid crystal polymer (LCP) substrates. The PVD SiC thin films were deposited directly onto the antennas by RF sputtering at room temperature at a chamber pressure of 30 mTorr and a power level of 300 W. The SiC film thickness is 450 nm. The return loss and radiation patterns were measured before and after the SiC-coated antennas were submerged into perchloric acid for 1 hour. No degradation in RF performance or physical integrity of the antenna was observed.

  10. Industrial inline PVD metallization for silicon solar cells with laser fired contacts leading to 21.8% efficiency

    OpenAIRE

    Nekarda, J.; Reinwand, D.; Hartmann, P.; Preu, R.

    2010-01-01

    In this contribution we present the latest results of our experiments in regard to an industrially feasible inline physical vapor deposition (PVD) metallization method for the rear side of passivated solar cells. In an earlier publication, the quality of such processed layers and the feasibility of the tool was already shown and compared with a commonly used laboratory process based on electron beam evaporation. Since then a difference in the Voc potential in the range of ~ 4 mV between both ...

  11. Development of a PVD-based manufacturing process of monolithic LEU irradiation targets for {sup 99}Mo production

    Energy Technology Data Exchange (ETDEWEB)

    Hollmer, Tobias

    2015-08-03

    {sup 99}Mo is the most important radioisotope in nuclear medicine. It is produced by fission of uranium in irradiation targets. The usage of cylindrical monolithic targets can ensure a safe supply of {sup 99}Mo and at the same reduce the amount of highly radioactive waste generated during production. To manufacture these targets, a novel PVD-based technique was developed. Both the feasibility and the high efficiency of this process were demonstrated in a prototype apparatus.

  12. Studies of steered arc motion and macroparticle production in PVD processing

    International Nuclear Information System (INIS)

    Craven, A.L.

    2000-03-01

    During the past decade the production industry has constantly strived to improve performance and cut costs, this has been aided by the development of high performance tools. The advancement of these tools has been accomplished by the application of hard wearing, low friction, coatings. A key process in the production of such coatings is Physical Vapour Deposition (PVD). Interest in such thin films has led to much research effort, both academic and industrial, being devoted to the area. In order that these advancements in technology continue, research into the fundamental aspects of PVD is required. This thesis describes research and experimental studies which have been performed to study the effect of 'steering' an electric arc on various aspects of its behaviour. 'Steering' of the arc is achieved by applying external magnetic fields which allow the guidance of the path of the arc. Work by earlier authors has aimed to control the arc more fully. The research presented here is based of a novel electromagnetic three coil steering array of cylindrical geometry. With such coils it is possible to vary the field profiles to a greater degree than has been previously achieved, permitting a greater range of steering arrangements/fields to be applied. The research presented is divided into two distinct areas: Firstly a number of experiments were performed to assess the effectiveness of the new steering coils on the motion of the arc. A personal computer was used here along with new arc motion monitoring electronics. This enabled the simultaneous measurement of the orbital transit times and also the degree of travel perpendicular to the steered direction of motion of the arc, as it traversed the surface of the cathode. Such information was then used to produce values for standard deviation of the arc from its steered path, velocity of the arc and a diffusion constant related to the motion of the are. Such values then allowed evaluation of the stochastic model of arc motion

  13. Cutting Performance of Low Stress Thick TiAlN PVD Coatings during Machining of Compacted Graphite Cast Iron (CGI

    Directory of Open Access Journals (Sweden)

    Kenji Yamamoto

    2018-01-01

    Full Text Available A new family of physical vapor deposited (PVD coatings is presented in this paper. These coatings are deposited by a superfine cathode (SFC using the arc method. They combine a smooth surface, high hardness, and low residual stresses. This allows the production of PVD coatings as thick as 15 µm. In some applications, in particular for machining of such hard to cut material as compacted graphite iron (CGI, such coatings have shown better tool life compared to the conventional PVD coatings that have a lower thickness in the range of up to 5 μm. Finite element modeling of the temperature/stress profiles was done for the SFC coatings to present the temperature/stress profiles during cutting. Comprehensive characterization of the coatings was performed using XRD, TEM, SEM/EDS studies, nano-hardness, nano-impact measurements, and residual stress measurements. Application of the coating with this set of characteristics reduces the intensity of buildup edge formation during turning of CGI, leading to longer tool life. Optimization of the TiAlN-based coatings composition (Ti/Al ratio, architecture (mono vs. multilayer, and thickness were performed. Application of the optimized coating resulted in a 40–60% improvement in the cutting tool life under finishing turning of CGI.

  14. Investigations on Wear Mechanisms of PVD Coatings on Carbides and Sialons

    Directory of Open Access Journals (Sweden)

    Staszuk M.

    2017-12-01

    Full Text Available The paper presents the results on the wear resistance of PVD coatings on cutting inserts made from sintered carbide and sialon ceramics. The exploitative properties of coatings in technological cutting trials were defined in the paper, which also examined the adhesion of coatings to the substrate, the thickness of the coating, and the microhardness. As a result, it was found that isomorphic coating with AlN-h phase of covalent interatomic bonds exhibits much better adhesion to the sialon substrate than isomorphic coating with titanium nitride TiN. These coatings assure the high wear resistance of the coated tools, and the high adhesion combined with the high microhardness and fine-grained structure assure an increase in the exploitative life of the coated tools. In the case of coatings on substrate made from sintered carbide, there was a significant influence on the properties of the tools coated with them as concerns the existence of the diffusion zone between the substrate and the coating.

  15. Evaluation of Osseous Integration of PVD-Silver-Coated Hip Prostheses in a Canine Model

    Directory of Open Access Journals (Sweden)

    Gregor Hauschild

    2015-01-01

    Full Text Available Infection associated with biomaterials used for orthopedic prostheses remains a serious complication in orthopedics, especially tumor surgery. Silver-coating of orthopedic (megaprostheses proved its efficiency in reducing infections but has been limited to surface areas exposed to soft tissues due to concerns of silver inhibiting osseous integration of cementless stems. To close this gap in the bactericidal capacity of silver-coated orthopedic prostheses extension of the silver-coating on surface areas intended for osseous integration seems to be inevitable. Our study reports about a PVD- (physical-vapor-deposition- silver-coated cementless stem in a canine model for the first time and showed osseous integration of a silver-coated titanium surface in vivo. Radiological, histological, and biomechanical analysis revealed a stable osseous integration of four of nine stems implanted. Silver trace elemental concentrations in serum did not exceed 1.82 parts per billion (ppb and can be considered as nontoxic. Changes in liver and kidney functions associated with the silver-coating could be excluded by blood chemistry analysis. This was in accordance with very limited metal displacement from coated surfaces observed by laser ablation inductively coupled plasma-mass spectrometry (LA-ICP-MS 12 months after implantation. In conclusion our results represent a step towards complete bactericidal silver-coating of orthopedic prostheses.

  16. Wear of different PVD coatings at industrial fine-blanking field tests

    Directory of Open Access Journals (Sweden)

    Liina Lind

    2015-09-01

    Full Text Available Thin hard physical vapor deposited (PVD coatings play significant role on wear performance of fine-blanking punches in the presence of extremely high contact stresses. Nevertheless it seems that in blanking or fine-blanking the coatings are selected based on coincidence, trial-error-method or latest trends. There is limited information about planning and conducting the fine-blanking industrial field tests and measuring the wear of different coatings. In the present study a set of fine-blanking punches and laboratory specimens were prepared with three coatings – TiCN, nACRo and nACo. As substrate material Böhler S390 Microclean high speed steel was used. Coating mechanical properties (modulus of elasticity and nanohardness were measured and wear rate with alumina ball was determined using the reciprocating sliding test. Wear of coatings was measured from punches after industrial use. All of the tested coatings showed high variance of wear. However coatings nACo and nACRo have better average wear resistance in fine-blanking compared with the well-known TiCN. Industrial field tests show correlation to the ratio elastic strain to failure H/E.DOI: http://dx.doi.org/10.5755/j01.ms.21.3.7249

  17. The effect of MEVVA ion implantation on the tribological properties of PVD-TiN films

    International Nuclear Information System (INIS)

    Manory, R.; Mollica, S.

    1998-01-01

    The present work is the first study in which the effects of metal evaporation vacuum (MEVVA) implantation are studied on TiN of the PVD type which is commercially available in Australia. The MEVVA ion implanter differs from the 'conventional' type of ion implanter in the fact that it has a high throughput of metal ions which are not mass analysed and therefore has more potential for industrial non-electronic applications. TiN-coated steel samples have been implanted with two types of species - one light and one heavy - C + and W + respectively. The samples were analysed by Rutherford backscattering (RBS) and x-ray diffraction (XRD). The tribological performance was assessed by pin-on-disc and microhardness. The results show that carbon implantation was very effective in improving the friction coefficient by the formation of a carbonaceous layer on the surface. XRD also shows formation of TiC in the near surface region. W implantation does not improve the friction coefficient but improves the lifetime of the coating. Unimplanted films fail in the pin-on-disk test after 7000 cycles, whereas implanted films are still well adhered after 18000 cycles

  18. Computer Simulation of the Relationship between Selected Properties of PVD Coatings

    Directory of Open Access Journals (Sweden)

    Śliwa A.

    2016-06-01

    Full Text Available The possibility to apply the Finite Element Method to calculate internal stresses which occur in Ti+TiN, Ti+Ti(CxN1-x and Ti+TiC coatings obtained in the magnetron PVD process on the sintered high-speed steel of the PM HS6-5-3-8 type. For the purpose of computer simulation of internal stresses in coatings with the use of MES, the correct model of analyzed specimens was worked out and then it was experimentally verified by comparison of calculation results with the results of computer simulation. Accurate analysis of correlations indicated especially strong dependence between internal stresses and microhardness and between microhardness and erosion resistance what created conditions for establishing the dependence between internal stresses obtained in the result of computer simulation and erosion resistance as basic functional quality of coating. It has essential practical meaning because it allows to estimate predictable erosion resistance of coating exclusively on the base of the results of computer simulation for used parameters in the process of coating manufacturing.

  19. Performance of PVD-Coated Carbide Tools When Turning Inconel 718 in Dry Machining

    Directory of Open Access Journals (Sweden)

    Gusri Akhyar Ibrahim

    2011-01-01

    Full Text Available Inconel 718 has found its niche in many industries, owing to its unique properties such as high oxidation resistance and corrosion resistance even at very high temperatures. Coated carbide tool with hard layer of PVD TiAlN is used to turn Inconel 718. Taguchi method with the orthogonal array L9 is applied in this experiment with the parameter cutting speed of 60–80 m/min, feed rate of 0.2–0.3 mm/rev, and depth of cut of 0.3–0.5 mm. The results show that depth of cut is a significant influence to the tool life. Cutting speed of 60 m/min, feed rate of 0.2 mm/rev, and depth of cut of 0.3 mm are the optimum parameters. The flank wear, crater wear, notch wear, and nose wear are the wear mechanisms on the carbide tool. Through the SEM, abrasion, attrition, and adhesion are the wear mechanisms which can be seen on the cutting tool.

  20. Tweedracht maakt macht. De PvdA, de doorbraak en de ontluikende polarisatiestrategie (1946-1966

    Directory of Open Access Journals (Sweden)

    B. Mellink

    2011-01-01

    Full Text Available Divide and Rule: The Dutch Labour Party (PvdA, the Breakthrough and the Emerging Polarisation Strategy (1946-1966In 1966, after a lengthy debate in the Dutch parliament, the Cals cabinet came to a sudden end. As a motion proposed by Norbert Schmelzer, the parliamentary leader of the prime minister’s own Catholic party precipitated the cabinet’s fall, ‘Schmelzer’s Night’ received an iconic status in Dutch political history. Many historians have interpreted Schmelzer’s Night as the birth of a Social Democratic ‘polarisation strategy’: differences between Left and Right were exaggerated in order to divide the confessional parties along ideological lines. Established analyses ascribe the development of this polarisation strategy to the ascendancy of a younger generation in Dutch politics. This article argues instead that the polarisation strategy of the late 1960s was not so much caused by a new generation, but rather emerged as a consequence of postwar Social Democrats’ efforts to abolish pillarisation (verzuiling in Dutch society.

  1. Mechanical properties of EB-PVD ZrO2 thermal barrier coatings

    International Nuclear Information System (INIS)

    Held, Carolin

    2014-01-01

    In this work, the elastic properties of thermal barrier coatings which were produced by electron-beam enhanced physical vapour deposition were investigated, as well as the dependency of the properties on the sample microstructure, the thermal treatment and the test method. For this purpose, not only commercial coatings were characterized, but also special sample material was used which consists of a 1 mm thick layer of EB-PVD TBC. This material was isothermally heat treated for different times at 950 C, 1100 C and 1200 C and then tested in a specially developed miniaturized bend test and by dynamic mechanical analysis. The sample material was tested by nanoindentation in order to measure the Young's modulus on a local scale, and the porosity of the samples was determined by microstructure analysis and porosimetry. The decrease of porosity could be connected with sintering and subsequent stiffening of the material. The test results are dependent on the tested volume. A small test volume leads to larger measured Young's moduli, while a large test volume yields lower values. The test volume also has an influence on the increase of stiffness during thermal exposure. With a small tested volume, a quicker increase of the Young's modulus was registered, which could be associated to the sintering of local structures.

  2. Evaluation of osseous integration of PVD-silver-coated hip prostheses in a canine model.

    Science.gov (United States)

    Hauschild, Gregor; Hardes, Jendrik; Gosheger, Georg; Stoeppeler, Sandra; Ahrens, Helmut; Blaske, Franziska; Wehe, Christoph; Karst, Uwe; Höll, Steffen

    2015-01-01

    Infection associated with biomaterials used for orthopedic prostheses remains a serious complication in orthopedics, especially tumor surgery. Silver-coating of orthopedic (mega)prostheses proved its efficiency in reducing infections but has been limited to surface areas exposed to soft tissues due to concerns of silver inhibiting osseous integration of cementless stems. To close this gap in the bactericidal capacity of silver-coated orthopedic prostheses extension of the silver-coating on surface areas intended for osseous integration seems to be inevitable. Our study reports about a PVD- (physical-vapor-deposition-) silver-coated cementless stem in a canine model for the first time and showed osseous integration of a silver-coated titanium surface in vivo. Radiological, histological, and biomechanical analysis revealed a stable osseous integration of four of nine stems implanted. Silver trace elemental concentrations in serum did not exceed 1.82 parts per billion (ppb) and can be considered as nontoxic. Changes in liver and kidney functions associated with the silver-coating could be excluded by blood chemistry analysis. This was in accordance with very limited metal displacement from coated surfaces observed by laser ablation inductively coupled plasma-mass spectrometry (LA-ICP-MS) 12 months after implantation. In conclusion our results represent a step towards complete bactericidal silver-coating of orthopedic prostheses.

  3. Impedance study on the corrosion of PVD and CVD titanium nitride coatings

    International Nuclear Information System (INIS)

    Elsener, B.; Rota, A.; Boehni, H.

    1989-01-01

    Titanium nitride (TiN) coatings, produced by physical (PVD) or chemical (CVD) vapor deposition techniques are used routinely to improve the wear and corrosion resistance of a surface. The main problem in using TiN as a protective coating in aggressive environements are pores and pinholes in the coating where the substrate is exposed to the electrolyte. In this work, the electrochemical and corrosion behaviour of TiN films on quartz glass, carbon steel, 304 and 316 stainless steel is studied by polarization curves and electrochemical impedance spectroscopy (EIS) in hydrochloric acid. It is shown that the TiN coating can be used successfully only on substrates that passivate easily. On mild steel rapid corrosion takes place at pores in the coating due to the very noble steady state potential of the TiN coating. The interaction of the metallic substrate with the TiN coating is discussed for the two limiting cases mild steel (active) and 316SS (passive). It is shown that the determination of the coating porosity is possible for the active substrate only. On the passive substrate the occurence of an additional time constant in the high frequency region of the spectrum qualitatively indicates the presence of pores. A quality control of the coatings based on this fact might be possible. (author) 15 refs., 6 figs., 2 tabs

  4. Enhanced Corrosion Resistance of PVD-CrN Coatings by ALD Sealing Layers

    Science.gov (United States)

    Wan; Zhang, Teng Fei; Ding, Ji Cheng; Kim, Chang-Min; Park, So-Won; Yang, Yang; Kim, Kwang-Ho; Kwon, Se-Hun

    2017-04-01

    Multilayered hard coatings with a CrN matrix and an Al2O3, TiO2, or nanolaminate-Al2O3/TiO2 sealing layer were designed by a hybrid deposition process combined with physical vapor deposition (PVD) and atomic layer deposition (ALD). The strategy was to utilize ALD thin films as pinhole-free barriers to seal the intrinsic defects to protect the CrN matrix. The influences of the different sealing layers added in the coatings on the microstructure, surface roughness, and corrosion behaviors were investigated. The results indicated that the sealing layer added by ALD significantly decreased the average grain size and improved the corrosion resistance of the CrN coatings. The insertion of the nanolaminate-Al2O3/TiO2 sealing layers resulted in a further increase in corrosion resistance, which was attributed to the synergistic effect of Al2O3 and TiO2, both acting as excellent passivation barriers to the diffusion of corrosive substances.

  5. Effect of Hf Additions to Pt Aluminide Bond Coats on EB-PVD TBC Life

    Science.gov (United States)

    Nesbitt, James; Nagaraj, Ben; Williams, Jeffrey

    2000-01-01

    Small Hf additions were incorporated into a Pt aluminide coating during chemical vapor deposition (CVD) on single crystal RENE N5 substrates. Standard yttria-stabilized zirconia top coats were subsequently deposited onto the coated substrates by electron beam-physical vapor deposition (EB-PVD). The coated substrates underwent accelerated thermal cycle testing in a furnace at a temperature in excess of 1121 C (2050 F) (45 minute hot exposure, 15 minute cool to approximately 121 C (250 F)) until the thermal barrier coating (TBC) failed by spallation. Incorporating Hf in the bond coat increased the TBC life by slightly more than three times that of a baseline coating without added Hf. Scanning electron microscopy of the spalled surfaces indicated that the presence of the Hf increased the adherence of the thermally grown alumina to the Pt aluminide bond coat. The presence of oxide pegs growing into the coating from the thermally grown alumina may also partially account for the improved TBC life by creating a near-surface layer with a graded coefficient of thermal expansion.

  6. Plasma thermal performance of a dual-process PVD/PS tungsten coating on carbon-based panels for nuclear fusion application

    International Nuclear Information System (INIS)

    Kim, Hyunmyung; Lee, Ho Jung; Kim, Sung Hwan; Jang, Changheui

    2016-01-01

    Highlights: • Plasma thermal performance of a dual-process PVD/PS W coating was evaluated. • Steady-state heat fluxes of 1–3 MW/m 2 were applied to the W coated specimens. • Less micro-pores and grain growth were observed for the dual-process coating. • Loss of coating thickness was observed for the simple PS W coating. • Dual-process PVD/PS W coating was resistant to erosion due to the surface PVD layer. - Abstract: Various tungsten (W) coating techniques have been used for the application of plasma facing material in nuclear fusion devices, which resulted in limited success. In this study, a dual-process W coating structure was developed on a graphite substrate to improve the thermal performance of the coating structure. The dual-process coating structure consisted of a thin (∼7 μm) multilayer W/Mo physical vapor deposition (PVD) coating layer deposited on top of the relatively thick (∼160 μm) plasma spray (PS) W coating on a graphite substrate panel. Then the coated sample was exposed to plasma heat flux of 1–3 MW/m 2 for 300 s. With addition of a thin surface PVD coating layer, the microstructure change in underlying PS W coating was substantially reduced compared to the simple PS W coating structure. The thickness of overall coating structure was maintained for the dual-process PVD/PS coated samples after the thermal loading tests, while a significant reduction in thickness due to surface erosion was observed for the simple PS W coated samples. The improvement in surface erosion resistance in the dual-process coating structure was discussed in view of the characteristics of PVD and PS coating layers.

  7. Plasma thermal performance of a dual-process PVD/PS tungsten coating on carbon-based panels for nuclear fusion application

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Hyunmyung; Lee, Ho Jung; Kim, Sung Hwan; Jang, Changheui, E-mail: chjang@kaist.ac.kr

    2016-11-01

    Highlights: • Plasma thermal performance of a dual-process PVD/PS W coating was evaluated. • Steady-state heat fluxes of 1–3 MW/m{sup 2} were applied to the W coated specimens. • Less micro-pores and grain growth were observed for the dual-process coating. • Loss of coating thickness was observed for the simple PS W coating. • Dual-process PVD/PS W coating was resistant to erosion due to the surface PVD layer. - Abstract: Various tungsten (W) coating techniques have been used for the application of plasma facing material in nuclear fusion devices, which resulted in limited success. In this study, a dual-process W coating structure was developed on a graphite substrate to improve the thermal performance of the coating structure. The dual-process coating structure consisted of a thin (∼7 μm) multilayer W/Mo physical vapor deposition (PVD) coating layer deposited on top of the relatively thick (∼160 μm) plasma spray (PS) W coating on a graphite substrate panel. Then the coated sample was exposed to plasma heat flux of 1–3 MW/m{sup 2} for 300 s. With addition of a thin surface PVD coating layer, the microstructure change in underlying PS W coating was substantially reduced compared to the simple PS W coating structure. The thickness of overall coating structure was maintained for the dual-process PVD/PS coated samples after the thermal loading tests, while a significant reduction in thickness due to surface erosion was observed for the simple PS W coated samples. The improvement in surface erosion resistance in the dual-process coating structure was discussed in view of the characteristics of PVD and PS coating layers.

  8. Characteristics of CrAlSiN + DLC coating deposited by lateral rotating cathode arc PVD and PACVD process

    Energy Technology Data Exchange (ETDEWEB)

    Lukaszkowicz, Krzysztof, E-mail: krzysztof.lukaszkowicz@polsl.pl [Institute of Engineering Materials and Biomaterials, Silesian University of Technology, Konarskiego St. 18A, 44-100 Gliwice (Poland); Sondor, Jozef, E-mail: j.sondor@liss.cz [LISS, a.s., Dopravni 2603, 756 61 Roznov p.R. (Czech Republic); Balin, Katarzyna, E-mail: katarzyna.balin@us.edu.pl [A. Chełkowski Institute of Physic, University of Silesia, Uniwersytecka 4, 40-007 Katowice (Poland); Kubacki, Jerzy, E-mail: jerzy.kubacki@us.edu.pl [A. Chełkowski Institute of Physic, University of Silesia, Uniwersytecka 4, 40-007 Katowice (Poland)

    2014-09-01

    Highlights: • The chemical composition of the CrAlSiN + DLC coatings was studied. • The coatings have nanostructural character with fine crystallites. • Their average size grain is less than 10 nm. • The coatings demonstrate friction coefficient within the range 0.05–0.07. • The coating demonstrated a dense cross-sectional morphology as well as good adhesion to the substrate. - Abstract: Coating system composed of CrAlSiN film covered by diamond-like carbon (DLC)-based lubricant, deposited on hot work tool steel substrate was the subject of the research. The CrAlSiN and DLC layers were deposited by PVD lateral rotating ARC-cathodes (LARC) and PACVD technology on the X40CrMoV5-1 respectively. HRTEM investigation shows an amorphous character of DLC layer. It was found that the tested CrAlSiN layer has a nanostructural character with fine crystallites while their average size is less than 10 nm. Based on the XRD pattern of the CrAlSiN, the occurrence of fcc phase was only observed in the coating, the texture direction 〈3 1 1〉 is perpendicular to the sample surface. Combined SEM, AES and ToF-SIMS studies confirmed assumed chemical composition and layered structure of the coating. The chemical distribution of the elements inside the layers and at the interfaces was analyzed by SEM and AES methods. It was shown that additional CrN layer is present between substrate and CrAlSiN coating. The atomic concentration of the particular elements of DLC and CrAlSiN layer was calculated from the XPS measurements. In sliding dry friction conditions the friction coefficient for the investigated elements is set in the range between 0.05 and 0.07. The investigated coating reveals high wear resistance. The coating demonstrated a dense cross-sectional morphology as well as good adhesion to the substrate.

  9. Resistencia a la corrosión y desgaste de recubrinnientos deTiN obtenidos por PVD

    Directory of Open Access Journals (Sweden)

    Conde, A.

    2005-12-01

    Full Text Available Surface hardening techniques for metallic alloys are widely used to achieve layers of very high hardness and corrosion and wear resistance. In the present paper TiN coatings are obtained by PVD on a tool steel. The films are characterized by SEM, X-ray diffraction and XPS. Corrosion behaviour in NaCl solution showed the importance of the presence of defects on the PVD coating due to the different electrochemical behaviour of the steel base. Pin-on-disk measurements at approximately 40% RH against a corundum (Al2O3 ball showed a significant decrease in the wear rate compared with the results for the standard tool steel.

    Los tratamientos de endurecimiento superficial de aleaciones metálicas se utilizan para lograr capas de muy elevada dureza, resistencia a la corrosión y desgaste. En este trabajo, se estudia el comportamiento de recubrimientos de TiN obtenidos mediante PVD sobre aceros de herramientas. Las capas obtenidas se caracterizan mediante microscopía electrónica de barrido, difracción de rayos X y XPS. Se analiza el comportamiento frente a la corrosión de las capas protectoras, así como la influencia del substrato en su comportamiento en soluciones de NaCl. Finalmente, se realizan ensayos de desgaste por deslizamiento en seco mediante la técnica de pin-on-disk, comprobándose la mayor resistencia de estas capas.

  10. Full Scale Model Test of Consolidation Acceleration on Soft Soil deposition with Combination of Timber Pile and PVD (Hybrid Pile)

    OpenAIRE

    Sandyutama, Y.; Samang, L.; Imran, A. M.; Harianto4, T.

    2015-01-01

    This research aims to analyze the effect of composite pile-PVD (hybrid pile) as the reinforcement in embankment on soft soil by the means of numerical simulation and Full-Scale Trial Embankment. The first phase cunducted by numerical analysis and obtained 6-8 meters hybrid pile length effective. Full-Scale trial embankment. was installed hybrid pile of 6 m and preloading of 4,50 height. Full-scale tests were performed to investigate the performances of Hybrid pile reinforcement. This research...

  11. Evaluación ergonómica de usuarios de PVD en la empresa: Construmer, SL

    OpenAIRE

    Martín, María Consuelo

    2012-01-01

    El objetivo de este informe es el de la evaluación ergonómica de los trabajadores como usuarios de PVD, y la estimación del nivel de riesgo que las condiciones de trabajo concretas respecto a éste, en el centro de trabajo referenciado arriba, pudieran provocar sobre los trabajadores que posean tal condición. El objeto proviene de la necesidad de dar cumplimiento a la exigencia legal impuesta por la ley 31/95, de 8 de Noviembre, sobre Prevención de Riesgos Laborales.

  12. LiFAP-based PVdF-HFP microporous membranes by phase-inversion technique with Li/LiFePO{sub 4} cell

    Energy Technology Data Exchange (ETDEWEB)

    Aravindan, V.; Vickraman, P. [Gandhigram Rural University, Department of Physics, Gandhigram (India); Sivashanmugam, A.; Thirunakaran, R.; Gopukumar, S. [Central Electrochemical Research Institute, Electrochemical Energy Systems Division, Karaikudi (India)

    2009-12-15

    Polyvinylidenefluoride-hexafluoropropylene-based (PVdF-HFP-based) gel and composite microporous membranes (GPMs and CPMs) were prepared by phase-inversion technique in the presence 10 wt% of AlO(OH){sub n} nanoparticles. The prepared membranes were gelled with 0.5-M LiPF{sub 3}(CF{sub 2}CF{sub 3}){sub 3} (lithium fluoroalkylphosphate, LiFAP) in EC:DEC (1:1 v/v) and subjected to various characterizations; the AC impedance study shows that CPMs exhibit higher conductivity than GPMs. Mechanical stability measurements on these systems reveal that CPMs exhibit Young's modulus higher than that of bare and GPMs and addition of nanoparticles drastically improves the elongation break was also noted. Transition of the host from {alpha} to {beta} phase after the loading of nanosized filler was confirmed by XRD and Raman studies. Physico-chemical properties, like liquid uptake, porosity, surface area, and activation energy, of the membranes were calculated and results are summarized. Cycling performance of Li/CPM/LiFePO{sub 4} coin cell was fabricated and evaluated at C/10 rate and delivered a discharge capacity of 157 and 148 mAh g {sup -1} respectively for first and tenth cycles. (orig.)

  13. Nanocomposite metal amorphous-carbon thin films deposited by hybrid PVD and PECVD technique.

    Science.gov (United States)

    Teixeira, V; Soares, P; Martins, A J; Carneiro, J; Cerqueira, F

    2009-07-01

    Carbon based films can combine the properties of solid lubricating graphite structure and hard diamond crystal structure, i.e., high hardness, chemical inertness, high thermal conductivity and optical transparency without the crystalline structure of diamond. Issues of fundamental importance associated with nanocarbon coatings are reducing stress, improving adhesion and compatibility with substrates. In this work new nanocomposite coatings with improved toughness based in nanocrystalline phases of metals and ceramics embedded in amorphous carbon matrix are being developed within the frame of a research project: nc-MeNxCy/a-C(Me) with Me = Mo, Si, Al, Ti, etc. Carbide forming metal/carbon (Me/C) composite films with Me = Mo, W or Ti possess appropriate properties to overcome the limitation of pure DLC films. These novel coating architectures will be adopted with the objective to decrease residual stress, improve adherence and fracture toughness, obtain low friction coefficient and high wear-resistance. Nanocomposite DLC's films were deposited by hybrid technique using a PVD-Physically Vapor Deposition (magnetron sputtering) and Plasma Enhanced Chemical Vapor Deposition (PECVD), by the use of CH4 gas. The parameters varied were: deposition time, substrate temperature (180 degrees C) and dopant (Si + Mo) of the amorphous carbon matrix. All the depositions were made on silicon wafers and steel substrates precoated with a silicon inter-layer. The characterisation of the film's physico-mechanical properties will be presented in order to understand the influence of the deposition parameters and metal content used within the a-C matrix in the thin film properties. Film microstructure and film hybridization state was characterized by Raman Spectroscopy. In order to characterize morphology SEM and AFM will be used. Film composition was measured by Energy-Dispersive X-ray analysis (EDS) and by X-ray photoelectron spectroscopy (XPS). The contact angle for the produced DLC's on

  14. MeCrAl coatings obtained by arc PVD and pack cementation processes on nickel base superalloys

    International Nuclear Information System (INIS)

    Swadzba, L.; Maciejny, A.; Formanek, B.; Mendala, B.

    1997-01-01

    The paper presents the results of researches on obtaining and structure of high temperature resistance coatings on superalloys. The coatings were deposited on nickel and nickel base superalloys in two stages. During the first stage, the NiCr and NiCrHf coatings were obtained by arc-PVD method. Basic technology, bias, arc current, rotation, parameters of deposition of NiCr and MeCrHf coatings were defined. The high efficiency of deposition of both single and two sources was observed. The targets were made by vacuum melting and machining. An influence of targets chemical composition on coating structure and chemical coatings composition was described. The second stage was made by pack cementation HTLA (high temperature low activity) on 1323 K chromoaluminizing process. These arc-PVD and diffusion (pack cementation) connected processes permitted to obtain MeCrAl and MeCrAlHf type of coatings. The morphology, structure and microchemical composition were characterized by scanning electron microscopy, X-ray microanalysis, energy dispersive X-ray spectroscopy and X-ray diffraction methods. (orig.)

  15. Reinforced PEI/PVdF Multicore-Shell Structure Composite Membranes by Phase Prediction on a Ternary Solution

    Directory of Open Access Journals (Sweden)

    Jihye Chae

    2018-04-01

    Full Text Available To construct a polyetherimide (PEI-reinforced polyvinylidene fluoride (PVdF composite membrane with multicore-shell structure, a ternary solution was prepared and electrospun by single-nozzle electrospinning. A theoretical prediction was made for the feasibility of complete distinction of two phases. The diameters of the membrane fibers and the PEI multi-core fibrils varied with the PEI ratio and the spinning time, respectively. The tensile strength and modulus were improved to 48 MPa and 1.5 GPa, respectively. The shrinkage of the membrane was only 6.6% at 180 °C, at which temperature the commercial PE separator melted down. The reinforcement in mechanical and thermal properties is associated with multiple PEI nanofibrils oriented along the fiber axis. Indeed, the unique morphology of self-assembled multicore-shell fibers plays an important role in their properties. All in all, PEI/PVdF membranes are appropriate for a lithium-ion battery application due to their high mechanical strength, excellent thermal stability, and controllable textural properties.

  16. Synthesis and electrochemical properties of Ti-doped DLC films by a hybrid PVD/PECVD process

    Science.gov (United States)

    Jo, Yeong Ju; Zhang, Teng Fei; Son, Myoung Jun; Kim, Kwang Ho

    2018-03-01

    Low electrical conductivity and poor adhesion to metallic substrates are the main drawbacks of diamond-like carbon (DLC) films when used in electrode applications. In this study, Ti-doped DLC films with various Ti contents were synthesized on metal Ti substrates by a hybrid PVD/PECVD process, where PECVD was used for deposition of DLC films and PVD was used for Ti doping. The effects of the Ti doping ratio on the microstructure, adhesion strength, and electrical and electrochemical properties of the DLC films were systematically investigated. An increase in the Ti content led to increased surface roughness and a higher sp2/sp3 ratio of the Ti-DLC films. Ti atoms existed as amorphous-phase Ti carbide when the Ti doping ratio was less than 2.8 at.%, while the nanocrystalline TiC phase was formed in DLC films when the Ti doping ratio was exceeded 4.0 at.%. The adhesion strength, electrical resistivity, electrochemical activity and reversibility of the DLC films were greatly improved by Ti doping. The influence of Ti doping ratio on the electrical and electrochemical properties of the DLC films were also investigated and the best performance was obtained at a Ti content of 2.8 at.%.

  17. Analysis of the photo voltage decay /PVD/ method for measuring minority carrier lifetimes in P-N junction solar cells

    Science.gov (United States)

    Von Roos, O.

    1981-01-01

    The photo voltage decay (PVD) method for the measurement of minority carrier lifetimes in P-N junction solar cells with cell thickness comparable to or even less than the minority carrier diffusion length is examined. The method involves the generation of free carriers in the quasi-neutral bulk material by flashes of light and the monitoring of the subsequent decay of the induced open-circuit voltages as the carriers recombine, which is dependent on minority carrier recombination lifetime. It is shown that the voltage versus time curve for an ordinary solar cell (N(+)-P junction) is proportional to the inverse minority carrier lifetime plus a factor expressing the ratio of diffusion length to cell thickness. In the case of an ideal back-surface-field cell (N(+)-P-P(+) junction) however, the slope is directly proportional to the inverse minority carrier lifetime. It is noted that since most BSF cells are not ideal, possessing a sizable back surface recombination velocity, the PVD measurements must be treated with caution and supplemented with other nonstationary methods.

  18. Development and evaluation of two PVD-coated β-titanium orthodontic archwires for fluoride-induced corrosion protection.

    Science.gov (United States)

    Krishnan, Vinod; Krishnan, Anand; Remya, R; Ravikumar, K K; Nair, S Asha; Shibli, S M A; Varma, H K; Sukumaran, K; Kumar, K Jyothindra

    2011-04-01

    The present research was aimed at developing surface coatings on β titanium orthodontic archwires capable of protection against fluoride-induced corrosion. Cathodic arc physical vapor deposition PVD (CA-PVD) and magnetron sputtering were utilized to deposit thin films of titanium aluminium nitride (TiAlN) and tungsten carbide/carbon (WC/C) coatings on β titanium orthodontic archwires. Uncoated and coated specimens were immersed in a high fluoride ion concentration mouth rinse, following a specially designed cycle simulating daily use. All specimens thus obtained were subjected to critical evaluation of parameters such as electrochemical corrosion behaviour, surface analysis, mechanical testing, microstructure, element release, and toxicology. The results confirm previous research that β titanium archwires undergo a degradation process when in contact with fluoride mouth rinses. The study confirmed the superior nature of the TiAlN coating, evident as many fewer changes in properties after fluoride treatment when compared with the WC/C coating. Thus, coating with TiAlN is recommended in order to reduce the corrosive effects of fluorides on β titanium orthodontic archwires. Copyright © 2010 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

  19. High performance a-IGZO thin-film transistors with mf-PVD SiO2 as an etch-stop-layer

    NARCIS (Netherlands)

    Nag, M.; Steudel, S.; Bhoolokam, A.; Chasin, A.; Rockele, M.; Myny, K.; Maas, J.; Fritz, T.; Trube, J.; Groeseneken, G.; Heremans, P.

    2014-01-01

    In this work, we report on high-performance bottom-gate top-contact (BGTC) amorphous-Indium-Gallium-Zinc-Oxide (a-IGZO) thin-film transistor (TFT) with SiO2 as an etch-stop-layer (ESL) deposited by medium frequency physical vapor deposition (mf-PVD). The TFTs show field-effect mobility (μFE) of

  20. Laveren tussen ontspanning en solidariteit: de PvdA en de FNV ten tijde van de Poolse crisis (1980-1982)

    NARCIS (Netherlands)

    Miedema, C.

    2013-01-01

    The Polish independent trade union Solidarność appeared in a time of rising tension between East and West. This created a dilemma for Western left-wing movements: maintain solidarity with the Polish workers or continue the détente policy of the 1970s? The Dutch social democratic party PvdA and the

  1. Reducing virulence of the human pathogen Burkholderia by altering the substrate specificity of the quorum-quenching acylase PvdQ

    NARCIS (Netherlands)

    Koch, Gudrun; Nadal-Jimenez, Pol; Reis, Carlos R.; Muntendam, Remco; Bokhove, Marcel; Melillo, Elena; Dijkstra, Bauke W.; Cool, Robbert H.; Quax, Wim J.

    2014-01-01

    The use of enzymes to interfere with quorum sensing represents an attractive strategy to fight bacterial infections. We used PvdQ, an effective quorum-quenching enzyme from Pseudomonas aeruginosa, as a template to generate an acylase able to effectively hydrolyze C8-HSL, the major communication

  2. CrCuAgN PVD nanocomposite coatings: Effects of annealing on coating morphology and nanostructure

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Xingguang, E-mail: xingguangliu1@gmail.com [Department of Materials Science and Engineering, Sir Robert Hadfield Building, The University of Sheffield, Mappin Street, Sheffield, S1 3JD (United Kingdom); Iamvasant, Chanon, E-mail: ciamvasant1@sheffield.ac.uk [Department of Materials Science and Engineering, Sir Robert Hadfield Building, The University of Sheffield, Mappin Street, Sheffield, S1 3JD (United Kingdom); Liu, Chang, E-mail: chang.liu@sheffield.ac.uk [Department of Materials Science and Engineering, Sir Robert Hadfield Building, The University of Sheffield, Mappin Street, Sheffield, S1 3JD (United Kingdom); Matthews, Allan, E-mail: allan.matthews@manchester.ac.uk [Pariser Building - B24 ICAM, School of Materials, The University of Manchester, Manchester, M13 9PL (United Kingdom); Leyland, Adrian, E-mail: a.leyland@sheffield.ac.uk [Department of Materials Science and Engineering, Sir Robert Hadfield Building, The University of Sheffield, Mappin Street, Sheffield, S1 3JD (United Kingdom)

    2017-01-15

    Highlights: • Coatings with nitrogen content up to 16 at.% exhibit a metallic Cr solid solution, even after post-coat annealing at 300 °C and 500 °C. • At higher N/Cr atomic ratios (approaching Cr{sub 2}N stoichiometry), chromium was still inclined to exist in solid solution with nitrogen, rather than as a ceramic nitride phase, even after annealing at 500 °C. • Transportation of Cu and Ag to the surface depends on annealing temperature, annealing duration, nitrogen concentration and ‘global’ Cu + Ag concentration. • Incorporation of copper appears to be a powerful strategy to enhance Ag mobility at low concentration (∼3 at.% Ag in this study) under moderately high service temperature. • A significant decrease in friction coefficient was obtained at room temperature after annealing, or during sliding wear testing at elevated temperature. - Abstract: CrCuAgN PVD nanocomposite coatings were produced using pulsed DC unbalanced magnetron sputtering. This investigation focuses on the effects of post-coat annealing on the surface morphology, phase composition and nanostructure of such coatings. In coatings with nitrogen contents up to 16 at.%, chromium exists as metallic Cr with N in supersaturated solid solution, even after 300 °C and 500 °C post-coat annealing. Annealing at 300 °C did not obviously change the phase composition of both nitrogen-free and nitrogen-containing coatings; however, 500 °C annealing resulted in significant transformation of the nitrogen-containing coatings. The formation of Ag aggregates relates to the (Cu + Ag)/Cr atomic ratio (threshold around 0.2), whereas the formation of Cu aggregates relates to the (Cu + Ag + N)/Cr atomic ratio (threshold around 0.5). The primary annealing-induced changes were reduced solubility of Cu, Ag and N in Cr, and the composition altering from a mixed ultra-fine nanocrystalline and partly amorphous phase constitution to a coarser, but still largely nanocrystalline structure. It was also

  3. Evolution of self-organization in nano-structured PVD coatings under extreme tribological conditions

    Energy Technology Data Exchange (ETDEWEB)

    Fox-Rabinovich, G., E-mail: gfox@mcmaster.ca [Department of Mechanical Engineering, McMaster University, 1280 Main St. W., Hamilton, ON, Canada L8S 4L7 (Canada); Kovalev, A. [Surface Phenomena Researches Group, CNIICHERMET, 9/23, 2-nd Baumanskaya Street, Moscow 105005 (Russian Federation); Aguirre, M.H. [Laboratory of Advanced Microscopy, Institute of Nanoscience of Aragón, University of Zaragoza, 50018 Zaragoza (Spain); Yamamoto, K. [Materials Research Laboratory, Kobe Steel Ltd, 1-5-5 Takatsuda-dai, Nishi-ku, Kobe 651-2271, Hyogo (Japan); Veldhuis, S. [Department of Mechanical Engineering, McMaster University, 1280 Main St. W., Hamilton, ON, Canada L8S 4L7 (Canada); Gershman, I. [All-Russian Railway Research Institute, 10 Third Mytishchinskaya Street, Moscow 29851 (Russian Federation); Rashkovskiy, A. [Surface Phenomena Researches Group, CNIICHERMET, 9/23, 2-nd Baumanskaya Street, Moscow 105005 (Russian Federation); Endrino, J.L. [Albengoa Research, Energia Solar 1, Palmas Altas, Seville 41014 (Spain); Beake, B. [Micro Materials Limited, Willow House, Yale Business Village, Ellice Way, Wrexham LL13 7YL (United Kingdom); Dosbaeva, G. [Department of Mechanical Engineering, McMaster University, 1280 Main St. W., Hamilton, ON, Canada L8S 4L7 (Canada); Wainstein, D. [Surface Phenomena Researches Group, CNIICHERMET, 9/23, 2-nd Baumanskaya Street, Moscow 105005 (Russian Federation); Yuan, Junifeng; Bunting, J.W. [Department of Mechanical Engineering, McMaster University, 1280 Main St. W., Hamilton, ON, Canada L8S 4L7 (Canada)

    2014-04-01

    Highlights: • The evolution of self-organization under extreme frictional conditions has been studied. • Comprehensive characterization of the tribo-films was made using various surface analytical techniques. • During the running-in stage, mullite tribo-ceramics predominate on the surface of the nano-multilayer coating, establishing a functional hierarchy within the layer of tribo-films. • It is possible to control tribo-film evolution during self-organization by means of an increase in structural complexity and the non-equilibrium state of the surface engineered layer. - Abstract: The evolution of the self-organization process where dissipative structures are formed under the extreme frictional conditions associated with high performance dry machining of hardened steels has been studied in detail. The emphasis was on the progressive studies of surface transformations within multilayer and monolayer TiAlCrSiYN-based PVD coatings during the running-in stage of wear when self-organization process occurs. The coating layer was characterized by high resolution electron energy-loss spectroscopy (HREELS). It is shown that the nano-multilayer coating possesses higher non-equilibrium structure in comparison to the monolayer. Comprehensive studies of the tribo-films (dissipative structures) formed on the friction surface were made using a number of advanced surface characterization techniques such as X-ray photoelectron spectroscopy (XPS) and X-ray absorption near edge structure (XANES). The data obtained for the tribo-films was combined with the detailed TEM studies of the structural and phase transformations within the underlying coating layer. This data was related to the micro-mechanical characteristics of the coating layer and its wear resistance. It was demonstrated that the evolution of the self-organization process is strongly controlled by the characteristics of the tribo-films formed at different stages of the wear process. Within running-in stage (after

  4. Formation and investigation of multilayer nanostructured coatings TiN/MoN for different layers thicknesses with c-pvd

    International Nuclear Information System (INIS)

    Pogrebnyak, A.D.; Bondar, O.V.; Postol'nyj, B.A.; Andreev, A.A.; Abadias, G.; Beresnev, V.M.; Sobol', O.B.

    2013-01-01

    Multilayer coatings based on TiN/MoN were obtained using the vacuum arc evaporation cathode method (C-PVD). Multilayers thickness was in the range 6,7 ÷ 8,7 μm and monolayers thickness was 2, 10, 20 and 40 nm. Vacuum-arc unit Bulat 6 was used for depositions. For the analysis of multilayer structures and properties of nanostructured coatings XRD analysis method was used (D8 ADVANCE, Bruker). For elemental composition and morphology investigation of the surface layers and multilayered coatings SEM (JEOL-7001F) with EDX attachment was used. Also HRTEM method was used to analyze the phase composition. In addition, this article provides investigation of hardness by Micro-Hardness Tester CSM (Switzerland). AFM was used for additional analysis of the topography and surface roughness of these coatings. This investigation have revealed the relationship between the layers thicknesses, substrate potential, the annealing process, physical and mechanical properties of samples. (authors)

  5. Microstructure evolution during annealing of TiAl/NiCoCrAl multilayer composite prepared by EB-PVD

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Rubing, E-mail: zrb86411680@126.com [Department of Mechanics, School of Civil Engineering, Beijing Jiaotong University, Beijing 100044 (China); Zhang, Deming [Beijing General Research Institute of Mining and Metallurgy, Beijing 100044 (China); Chen, Guiqing [Center for Composite Materials, Harbin Institute of Technology, Harbin 150001 (China); Wang, Yuesheng [Department of Mechanics, School of Civil Engineering, Beijing Jiaotong University, Beijing 100044 (China)

    2014-07-01

    TiAl/NiCoCrAl laminate composite sheet with a thickness of 0.4–0.6 mm as well as a dimension of 150 mm × 100 mm was fabricated successfully by using electron beam physical vapor deposition (EB-PVD) method. The annealing treatment was processed at 1123 and 1323 K for 3 h in a high vacuum atmosphere, respectively. The phase composition and microstructure of TiAl/NiCoCrAl microlaminated sheet have been analyzed by X-ray diffraction (XRD), scanning electron microscopy (SEM) and transmission electron microscopy (TEM). Based on the sheet characterization and results of the microstructure evolution during annealing treatment process, the diffusion mechanism of interfacial reaction in TiAl/NiCoCrAl microlaminate was investigated and discussed.

  6. Production and characterization of multilayer coatings of Ti/TiN on AISI 316L stainless steel by the PVD technique of cathodic arc ion plating

    International Nuclear Information System (INIS)

    Forlerer, Elena; Rodriguez, Fernando; Mingolo, Norma

    2006-01-01

    Multilayer coatings were produced from bi-layers (compound layers) of Ti/TiN in a PVD reactor of cathodic arc ion plating. The process was carried out at an Argon gas pressure of 5x10 -3 Torr for the interlayer of Ti and a nitrogen + argon pressure of 2x10 -2 Torr for the deposit of TiN and a Bias voltage of -500V for the Ti layer and -100V for the TiN layer. The arc current held constant at 80 amp. The samples were kept at high temperatures ≥ 300 o C, mounted on a rotating system that held the test piece 15-25 cm from the Ti electrode. Certified composition AISI 316L and AISI 410 stainless steel were used for the substrate. Coatings with one or two compound layers with similar thicknesses were made. The coatings were characterized mechanically by adherence, thickness and microhardness by Vickers indentation with 25g loads. The texture was studied by X-ray diffraction and present phases and residual tensions were determined. The results of the X-ray diffraction show the presence of the mostly TiN phase, with fcc structure in the mono-layer and the bi-layer. Residual tensions are compressive and elevated due to the expansion of the TiN network during the deposition process. Measurements of the bi-layers at different angles showed a relaxing of the tensions close to the surface, which could be due to the effect of the second interlayer of Ti. Preferential orientations associated with the growth process of the layers and the developed microstructure were detected in the TiN (CW)

  7. Enriquecimiento en Si mediante PVD de chapas magnéticas convencionales para aplicaciones a altas frecuencias

    Directory of Open Access Journals (Sweden)

    Molina Aldareguía, J.

    2000-06-01

    Full Text Available The present work deals with the viability of a method for Si enrichment of conventional Fe-3%Si sheets, by means of physical vapour deposition of Si at its surface and subsequent diffusion heating. The aim is to obtain magnetic sheets with a Si content of 6.5wt%, for they show higher resistivity and null magnetostriction, leading to lower energy losses and solving the noise problems at high frequencies. The PVD deposited films, with ~5 μm thickness, show good adhesion to the substrate. Concerning the heat treatment, there is a critical heating rate between 5 and 15°/min, above which delamination of the film is observed without formation of intermetallics at the interface. At 3°/min the conditions for the formation of intermetallics are given. Direct heating up to 800°C leads to the formation of a Fe3Si(α1 surface layer, which, being brittle, does not delaminate during the heating process. Subsequent heating up to temperatures around 1200°C allows the homogenisation of the sheet composition. There is evidence of Kirkendall effect in the diffusion couple Fe3Si(α1/Fe(α, due to the fact that the diffusion of Fe in Fe3Si(α1 is faster than the diffusion of Si in Fe(α.

    El presente trabajo estudia la viabilidad de un método para enriquecer en Si chapas de Fe-3%Si convencionales, depositando Si en su superficie mediante PVD y sometiéndolas a un tratamiento térmico de difusión. Se trata de obtener chapas magnéticas con un contenido en Si de un 6,5% en peso, ya que éstas presentan mayor resistividad y magnetoestricción nula, reduciendo las pérdidas y solucionando los problemas de ruido a altas frecuencias. Las capas depositadas por PVD, de espesores ~5 μm, presentan buena adherencia al substrato. En cuanto al tratamiento térmico, se observa que hay una velocidad de calentamiento crítica entre 5 y 15°/min, por encima de la cual la película se despega sin llegarse a formar intermetálicos en la intercara. A 3°/min se dan las

  8. The limits of application of variable-energy slow positron beams for investigating TiN hard coatings prepared by PVD

    International Nuclear Information System (INIS)

    Marek, T.; Suevegh, K.; Vertes, A.; Szeles, Cs.; Lynn, K.G.

    2000-01-01

    Samples of TiN hard coatings prepared by physical vapour deposition (PVD) were investigated by means of depth-sensitive positron annihilation spectroscopy. The results indicate that the samples are at the limits of the applicability of this method presumably due to the high defect concentration. Though the samples are thoroughly characterized by other independent methods, they might not be sufficient to explain all aspects of positron-solid interactions in these cases. (author)

  9. High-temperature resistant MeCrAlY+Al coatings obtained by ARC-PVD method on Ni Base superalloys

    International Nuclear Information System (INIS)

    Swadzba, L.; Maciejny, A.; Mendala, B.; Supernak, W.

    1999-01-01

    Investigations of obtaining high temperature coatings on the Ni base superalloys by the ARC-PVD method, using exothermic reaction processes between Ni and Al with NiAl intermetallic formation are presented in the article. By the diffusion heating at 1050 o C NiAl high temperature diffusion coating containing 21% at. Al and 50 μm thick was obtained. In the next stage coatings with more complex chemical composition NiCoCrAlY were formed. The two targets were applied for formation of complex NiCoCrAlY coatings. The good consistence between the chemical composition of the targets and the coatings and an uniform distribution of elements in the coatings were shown. Then the surface was covered with aluminium also by the ARC-PVD method. In the vacuum chamber of the equipment a synthesis reaction between NiCoCrAlY and Al with the formation NiAl intermetallics of high Co, Cr, Y content was initiated by the changes in process parameters. The final heat treatment of coatings was conducted in the air and vacuum at 1050 o C. The strong segregation of yttrium in to the oxide scale in the specimens heated in the air was shown. It was possible to obtain NiAl intermetallic phase coatings modified by Co, Cr and Y by the ARC-PVD method. An example of the application of this method for the aircraft engine turbine blades was presented. Method of ARC-PVD gives the possibility chemical composition and high resistance to oxidizing and hot corrosion. (author)

  10. Composite Layers “MgAl Intermetalic Layer / PVD Coating” Obtained On The AZ91D Magnesium Alloy By Different Hybrid Surface Treatment Methods

    Directory of Open Access Journals (Sweden)

    Smolik J.

    2015-06-01

    Full Text Available Magnesium alloys have very interesting physical properties which make them ‘materials of the future’ for tools and machine components in many industry areas. However, very low corrosion and tribological resistance of magnesium alloys hampers the implementation of this material in the industry. One of the methods to improve the properties of magnesium alloys is the application of the solutions of surface engineering like hybrid technologies. In this paper, the authors compare the tribological and corrosion properties of two types of “MgAlitermetalic / PVD coating” composite layers obtained by two different hybrid surface treatment technologies. In the first configuration, the “MgAlitermetalic / PVD coating” composite layer was obtained by multisource hybrid surface treatment technology combining magnetron sputtering (MS, arc evaporation (AE and vacuum heating methods. The second type of a composite layer was prepared using a hybrid technology combined with a diffusion treatment process in Al-powder and the electron beam evaporation (EB method. The authors conclude, that even though the application of „MgAlitermetalic / PVD coating” composite layers can be an effective solution to increase the abrasive wear resistance of magnesium alloys, it is not a good solution to increase its corrosion resistance.

  11. Study the effect of ion-complex on the properties of composite gel polymer electrolyte based on Electrospun PVdF nanofibrous membrane

    International Nuclear Information System (INIS)

    Li, Weili; Xing, Yujin; Wu, Yuhui; Wang, Jiawei; Chen, Lizhuang; Yang, Gang; Tang, Benzhong

    2015-01-01

    In this paper, nanofibrous membranes based on poly(vinylidene fluoride) (PVdF) doped with ion-complex (SiO 2 -PAALi) were prepared by electrospinning technique and the corresponding composite gel-polymer electrolytes (CGPEs) were obtained after being activated in liquid electrolyte. The microstructure, physical and electrochemical performances of the nanofibrous membranes and the corresponding CGPEs were studied by various measurements such as Fourier Transform Infrared Spectroscopy(FTIR), Scanning Electron Microscope (SEM), Differential Scanning Calorimetry (DSC), Thermal Gravimetric Analysis (TGA), Stress-strain test, Linear Sweep Voltammetry (LSV), AC impedance measurement and Charge/discharge cycle test. As to the ion-complex doped nanofibrous membranes, PVdF can provide mechanical support with network structure composed of fully interconnection; while the ion-complexes are absorbed onto the surface of the PVdF nanofibers evenly instead of being aggregated. With the help of doped ion-complex, the prepared nanofibrous membranes present good liquid electrolyte absorbability, excellent mechanical performance, and high decomposition temperature. For the corresponding CGPEs, they possess high ionic conductivity, wide electrochemical window, and good charge/discharge cycle performance

  12. Structure of MeCrAlY + AlSi coatings deposited by Arc-PVD method on CMSX4 single crystal alloy

    International Nuclear Information System (INIS)

    Swadzba, L.; Hetmanczyk, M.; Mendala, B.; Saunders, S.R.J.

    2002-01-01

    Investigations of depositing high temperature resistant coatings on the Ni base superalloys by Arc-PVD method using exothermic reaction processes between Ni and Al with NiAl intermetallic formation are presented in the article. By the diffusion heating at 1050 o C in vacuum, NiAl diffusion coating containing 21% at. Al and 50 μm thick were obtained. In the next stage coatings with more complex chemical composition - MeCrAlY were formed. The MeCrAlY coatings were made from two targets. Good correlation between the chemical composition of the targets and a uniform distribution of elements in the coatings was shown. Then the surface was also covered with aluminium by the Arc-PVD method . In the vacuum chamber of the equipment a synthesis reaction between NiCoCrAlY and Al with the formation of NiAl intermetallics of high Co, Cr, Y content was initiated. The final heat treatment of coatings was conducted in vacuum at 1323 K. Strong segregation of yttrium into the oxide scale in the specimens heated in the air was shown. It was possible to form NiAl and intermetallics phase coatings modified by Co, Cr and Y by the Arc-PVD method. The coatings were formed on a single crystal CMSX-4. The structure, morphology and phase composition of coatings was carried out. (author)

  13. Effect of PbI{sub 2} deposition rate on two-step PVD/CVD all-vacuum prepared perovskite

    Energy Technology Data Exchange (ETDEWEB)

    Ioakeimidis, Apostolos; Christodoulou, Christos; Lux-Steiner, Martha; Fostiropoulos, Konstantinos, E-mail: fostiropoulos@helmholtz-berlin.de

    2016-12-15

    In this work we fabricate all-vacuum processed methyl ammonium lead halide perovskite by a sequence of physical vapour deposition of PbI{sub 2} and chemical vapour deposition (CVD) of CH{sub 3}NH{sub 3}I under a static atmosphere. We demonstrate that for higher deposition rate the (001) planes of PbI{sub 2} film show a higher degree of alignment parallel to the sample's surface. From X-ray diffraction data of the resulted perovskite film we derive that the intercalation rate of CH{sub 3}NH{sub 3}I is fostered for PbI{sub 2} films with higher degree of (001) planes alignment. The stoichiometry of the produced perovskite film is also studied by Hard X-ray photoelectron spectroscopy measurements. Complete all-vacuum perovskite solar cells were fabricated on glass/ITO substrates coated by an ultra-thin (5 nm) Zn-phthalocyanine film as hole selective layer. A dependence of residual PbI{sub 2} on the solar cells performance is displayed, while photovoltaic devices with efficiency up to η=11.6% were achieved. - Graphical abstract: A two-step PVD/CVD processed perovskite film with the CVD intercalation rate of CH{sub 3}NCH{sub 3} molecules been fostered by increasing the PVD rate of PbI{sub 2} and prolonging the CVD time. - Highlights: • A simple PVD/CVD process for perovskite film production. • Increased PVD rate yields better alignment of the PbI{sub 2} (001) crystallite planes. • CH{sub 3}NH{sub 3}I intercalation process fostered by increased PbI{sub 2} PVD rate. • Stoichiometric CH{sub 3}NH{sub 3}PbI{sub 3} suitable as absorber in photovoltaic applications • Reduced PbI{sub 2} residue at the bottom of CH{sub 3}NH{sub 3}PbI{sub 3} improves device performance.

  14. Preparation of homogeneous isotopic targets with rotating substrate

    International Nuclear Information System (INIS)

    Xu, G.J.; Zhao, Z.G.

    1993-01-01

    Isotopically enriched accelerator targets were prepared using the evaporation-condensation method from a resistance heating crucible. For high collection efficiency and good homogeneity the substrate was rotated at a vertical distance of 1.3 to 2.5 cm from the evaporation source. Measured collection efficiencies were 13 to 51 μg cm -2 mg -1 and homogeneity tests showed values close to the theoretically calculated ones for a point source. Targets, selfsupporting or on backings, could be fabricated with this method for elements and some compounds with evaporation temperatures up to 2300 K. (orig.)

  15. Effect of nitrogen gas flow rate on the tribological properties of TiN coated HSS using CAE PVD technique

    International Nuclear Information System (INIS)

    Mubarak, A.; Hamzah, E.; Toff, M.R.M.

    2005-01-01

    High-Speed Steel (HSS) is a material that used in various Hi-Tech industries for many reasons. The aim of this study is to investigate the tribological properties of TiN (Titanium Nitride)-coated HSS. Using Physical Vapour Deposition (PVD) Cathodic Arc Evaporation (CAE) technique coated samples. The goal of this work is to determine usefulness of TiN coatings in order to improve tribological properties of HSS, as vastly use in cutting tool industry for various applications. A Pin-on-Disc test showed that the minimum value recorded for friction coefficient was reduced from 0.294 to 0.239 when the nitrogen gas flow rate was increased from 100 sccm to 200 sccm. The decrease in friction coefficient resulted from the reduction in macrodroplets by increasing the nitrogen gas flow rate during deposition. The worn surface morphology of the TiN coated HSS was observed on a Field Emission Scanning Electron Microscope (FE-SEM), and the elemental composition on the wear scar were investigated by means of EDXS. (Author)

  16. The Study of Selected Properties of Ti EB PVD Coating Deposited Onto Inner Tube Surface at Low Temperature

    Directory of Open Access Journals (Sweden)

    Kottfer D.

    2016-03-01

    Full Text Available This study investigates the selected properties of the thin Ti coating applied by activated evaporation EB PVD technique. This technique was used for the deposition of Ti thin coating onto inner surface of OKhN3 MFA steel tubes. Deposition process was carried out at temperature 200°C. Conventional type of coatings - monolayer Ti - was analyzed by standard techniques for surface status and quality assessment - coating thickness, chemical composition by EDX analysis, adhesion, hardness, roughness, and growth direction of columns at room temperature. Ti monolayer achieved roughness Ra equal from 0.42 μm to 0.47 μm. The resulting hardness was from 2 GPa to 8.5 GPa depending on the sample location inside the vacuum chamber. Placing of the coated surface also affected the direction of grain growth of Ti coating columns. The angles α of grain growth were found to be from 40° to 60°. Angle α increased two to three times more than the incidence angle β (from 12° to 28° of evaporated Ti particles. Values of the adhesion measured along the Ti growth direction were mostly higher (up to 10% or the same as those measured perpendicular to it.

  17. A novel monolithic LEU foil target based on a PVD manufacturing process for 99Mo production via fission.

    Science.gov (United States)

    Hollmer, Tobias; Petry, Winfried

    2016-12-01

    99 Mo is the most widely used radioactive isotope in nuclear medicine. Its main production route is the fission of uranium. A major challenge for a reliable supply is the conversion from highly enriched uranium (HEU) to low enriched uranium (LEU). A promising candidate to realize this conversion is the cylindrical LEU irradiation target. The target consists of a uranium foil encapsulated between two coaxial aluminum cladding cylinders. This target allows a separate processing of the irradiated uranium foil and the cladding when recovering the 99 Mo. Thereby, both the costs and the volume of highly radioactive liquid waste are significantly reduced compared to conventional targets. The presented manufacturing process is based on the direct coating of the uranium on the inside of the outer cladding cylinder. This process was realized by a cylindrical magnetron enhanced physical vapor deposition (PVD) technique. The method features a highly automated process, a good quality of the resulting uranium foils and a high material utilization. Copyright © 2016 Elsevier Ltd. All rights reserved.

  18. Controllable synthesis and defect-dependent photoluminescence properties of In2O3 nanostructures prepared by PVD

    Science.gov (United States)

    Jin, Changqing; Wei, Yongxing; Peterson, George; Zhu, Kexin; Jian, Zengyun

    2017-05-01

    In2O3 nanostructures were successfully synthesized via physical vapor deposition (PVD). It was found that the morphology of nanostuctures could be controlled by manipulation of the synthesis temperature, growth time, use of a Au-catalyst, selection of substrate material, and vapor pressure. A higher synthesis temperature is more favorable for the formation of 1D nanostructures. An increased growth time increased the width and length of the 1D nanostructures. Through the use of a Au-catalyst coated Si (1 0 0) substrate, we were able to preferentially synthesize (1 0 0) In2O3 nanostructures, even at lower growth temperatures. This research shows that a Au-catalyst is necessary for the formation of one-dimensional (1D) In2O3 nanostructures. Three dimensional (3D) octahedral nanoparticles are resultant from a Au-free Si (1 0 0) substrate. Al2O3 (1 0 0) substrates were found to be energetically favorable for the synthesis of nanofilms, not 1D nanostructures, regardless of the presence of Au-catalyst. The photoluminescence curves indicate that the defect related luminescence is not a function of morphology, but rather the ratio of the partial vapor pressures of the constituent elements (In and O), which were controlled by the growth pressure.

  19. Evolution of photo-stimulated luminescence of EB-PVD/(Ni, Pt)Al thermal barrier coatings

    International Nuclear Information System (INIS)

    Wen Mei; Jordan, Eric H.; Gell, Maurice

    2005-01-01

    Experiments are described which were designed to assess the suitability of photo-stimulated luminescence piezo-spectroscopy (PLPS) measurements as a basis for non-destructive inspection (NDI) and determination of life remaining of thermal barrier coatings (TBCs). Thermal cyclic tests were conducted on 7 wt.% Y 2 O 3 stabilized ZrO 2 (YSZ) electron beam physical vapor deposited (EB-PVD)/(Ni, Pt)Al/CMSX-4 TBCs at two temperatures 1151 and 1121 deg. C. The evolution of PLPS spectral characteristics (peak frequency shift, peak width and area ratio of peaks) was studied as a function of thermal cycles. It was observed that the average thermally grown oxide (TGO) stress and its standard deviation, and the area ratio of peaks show systematic change with thermal cycling, indicating that these characteristics can be used for NDI and determination of life remaining. The average TGO stress increases initially and then decreases monotonically with thermal cycling. The rate of change in the stress can be related to specimen life: the shallower the slope, the higher the life. The peak area ratio also decreases monotonically with cycling. The average TGO stress changes in a systematic manner versus remaining life fraction independent of temperature. Remaining life predictions were made based on average stress versus life fraction, which resulted in life assessments within ±13% of actual values excluding one specimen with abnormal behavior

  20. Karakteristik Morfologi Permukaan Pada Polimer PVdF-LiBOB-ZrO2 dan Potensinya untuk Elektrolit Baterai Litium

    Directory of Open Access Journals (Sweden)

    Etty Marti Wigayati

    2018-02-01

    Full Text Available Membran elektrolit polimer pada baterai litium ion berfungsi sebagai media transport ion dan sebagai separator antara anoda dan katoda. Dalam penelitian ini, telah dilakukan sintesis membran elektrolit polimer LiBOB (Lithium Bis Oksalato Borate dengan rumus kimia LiB(C2O42 dengan menggunakan Polyvilinidine fluoride (PVdF sebagai matriks dan bahan aditif  Zirkonium Oksida (ZrO2. Metoda yang dipergunakan adalah solution cast. Konsentrasi bahan aditif dibuat bervariasi. Membran yang terbentuk dikarakterisasi morfologi permukaan menggunakan Scanning Electrone Microscope (SEM, sifat elektrokimia dengan Cyclic Voltametric (CV dan kapasitas baterai dengan kurva charge discharge. Hasil penelitian menunjukkan bahwa morfologi permukaan rantai polimer saling berikatan dan tersusun dengan bagus. Pori tertutup oleh rantai polimer secara rata yang berikatan membentuk jaring dan saling bertumpukan pada keadaan amorf. Terjadi reaksi oksidasi dan reduksi pada sel baterai dengan kapasitas charge sekitar 24 mAh pada tegangan 4 volt, sedangkan kapasitas discharge bernilai sama sekitar 24 mAh pada tegangan 4 volt dengan penambahan 10% ZrO2.

  1. Analysis of the environmental and nature impacts of 'Building Bridges'. Coalition VVD-PvdA, October 29, 2012. A quick scan; Analyse van de milieu- en natuureffecten van 'Bruggen slaan'. Regeerakkoord VVD-PvdA d.d. 29 oktober 2012. Een quick-scan

    Energy Technology Data Exchange (ETDEWEB)

    Dietz, F. (ed.)

    2012-11-15

    The coalition between the political parties VVD (liberals) and PvdA (socialists) connects the transition to a sustainable economy and green growth to strengthening the competitive capacity of the Dutch economy. The role of the Dutch government in the coalition aims at creating a framework and to provide facilities to realize the transition. In this memo the results of an analysis of the impacts of the coalition are given for the themes Energy and Climate, Nature, Transport and Traffic, and Green Growth [Dutch] Het Regeerakkoord VVD-PvdA koppelt de transitie naar een duurzame economie en groene groei aan het versterken van het concurrentievermogen van de Nederlandse economie. De rol van de rijksoverheid wordt in het regeerakkoord met name ingevuld als kaderstellend en faciliterend. De PBL-notitie analyseert de effecten van het regeringsakkoord voor de thema's Energie en Klimaat, Natuur, Verkeer en Vervoer, en Groene groei.

  2. Studies on electrical conductivity and dielectric behaviour of PVdF ...

    Indian Academy of Sciences (India)

    35, No. 6, November 2012, pp. 969–975. c Indian Academy of Sciences. ... methacrylate) and 1·0 M NaI as salt have been synthesized using solution caste technique by varying the ... polymer electrolytes systems and composite polymer elec-.

  3. Comparison of effective relative dielectric permittivities obtained by three independent ways for CeO2-Sm2O3 films prepared by EB-PVD (+IBAD) techniques

    International Nuclear Information System (INIS)

    Kundracik, F.; Neilinger, P.; Hartmanova, M.; Nadazdy, V.; Mansilla, C.

    2011-01-01

    Ceria, as material with relatively high dielectric permittivity, ε r , and ability to form films on the Si substrate, is a candidate for the gate dielectrics in the MOS devices. Doping with suitable e.g. trivalent rare earth oxides and suitable treatment after deposition (preparation) can improve their properties, e.g. ionic conductivity, dielectric permittivity and mechanical hardness. In this work, the dielectric properties of CeO 2 + Sm 2 O 3 films prepared by electron beam physical vapour deposition (EB-PVD) and some of them simultaneously also by the Ar + ionic beam assisted deposition (IBAD) techniques are analysed. (authors)

  4. Thermal cycling behavior of EB-PVD TBCs on CVD platinum modified aluminide coatings

    Energy Technology Data Exchange (ETDEWEB)

    Xu, Zhenhua, E-mail: zhxubiam@aliyun.com; Wang, Zhankao; Huang, Guanghong; Mu, Rende; He, Limin

    2015-07-15

    Highlights: • The removed ridges at the grain boundaries with grit blasting. • The ridge, oxidation and cracking are features of damage initiation in TBCs. • Spalled location either at TGO/bond coat interface or inside of TGO layer. • The lower strain energy release rate within TGO layer can prolong of TBCs life. - Abstract: Thermal barrier coating systems (TBCs) including of chemical vapor deposited (Ni, Pt)Al bond coat with grit blasting process and electron beam physical vapor deposited Y{sub 2}O{sub 3}-stabilized-ZrO{sub 2} (YSZ) ceramic coating were investigated. The phase structures, surface and cross-sectional morphologies, cyclic oxidation behaviors and residual stresses of the TBCs were studied in detail. It was found that the fracture path traverses through the ceramic coating to TGO interface, as well as at the TGO to bond coat interface is obviously detected. The change in fracture plane occurs at grain boundaries. The ridge top spallation leads to separate of sufficient size to result in unstable fracture driven by the strain energy stored in the TGO. The bond coat can undergo a volume increase upon oxidation, so that a cavity, enlarged strictly by oxidation would be full to overflowing with TGO layer. The spalled location of the TBCs probably occurs either at the interface of TGO layer and bond coat or inside of TGO layer. The lower strain energy release rate within TGO layer during thermal cycling is beneficial to prolong of TBCs life. The lower is the compressive stress within TGO layer, the longer is the lifetime of TBCs.

  5. Improved mechanical properties of Ni-rich Ni3Al coatings produced by EB-PVD for repairing single crystal blades

    Institute of Scientific and Technical Information of China (English)

    Jing-Yong Sun; Yan-Ling Pei; Shu-Suo Li; Hu Zhang; Sheng-Kai Gong

    2017-01-01

    Active control of turbine blade tip clearance for aircraft engine continues to be a concern in engine operation,because turbine blades are subjected to wear and therefore cause an increasing tip clearance between the rotating blades and the shroud and also reduce the engine efficiency.In this work,a Ni-rich Ni3Al coating with γ'/γtwo-phase microstructure was deposited by electron beam physical vapor deposition (EB-PVD),which worked as repairing the worn blade tips of single crystal blades.Nb molten pool was used to increase the molten pool temperature and thus to enhance the deposition rate.The microstructures and mechanical properties can be modified by the deposition temperatures and the following heat treatments.All coatings consist of γ'and γ phases.At deposition temperature of 600 ℃,a dense microstructure can be achieved to produce a coating with grain size of ~ 1 μm and microhardness of ~HV 477.After being heated for 4 h at a temperature of 1,100 ℃,the coatings have a more uniform microstructure,and microhardness maintains at a high level of ~ HV 292.Effect of Hf and Zr on EB-PVD Ni3Al repair coating will be further investigated.

  6. Morphology and inhibition performance of Ag thin film as antimicrobial coating deposited by RF-PVD on 316 L stainless steel

    Science.gov (United States)

    Purniawan, A.; Khrisna, Y. S. A.; Rasyida, A.; Atmono, T. M.

    2018-04-01

    Foreign body related infection (FBRIs) is caused by forming biofilm of bacterial colony of medical equipment surfaces. In many cases, the FBRIs is still happened on the surface after medical sterilization process has been performed. In order to avoid the case, surface modification by antimicrobial coating was used. In this work, we present silver (Ag) thin film on 316 L stainless steel substrate surface was deposited using Radio Frequency Sputtering PVD (RF-PVD). The morphology of Ag thin film were characterized using SEM-EDX. Surface roughness of the thin film was measured by AFM. In addition, Kirby Bauer Test in Escherichia coli (E. coli) was conducted in order to evaluate the inhibition performance of the Ag thin film antimicrobial coating. Based on SEM and AFM results show that the particle size is increased from 523 nm to 708 nm and surface roughness from 9 to 20 nm for deposition time 10 minutes to 20 minutes, respectively. In addition, the inhibition layer of the coating is about 29 mm.

  7. GEP-based method to formulate adhesion strength and hardness of Nb PVD coated on Ti-6Al-7Nb aimed at developing mixed oxide nanotubular arrays.

    Science.gov (United States)

    Rafieerad, A R; Bushroa, A R; Nasiri-Tabrizi, B; Fallahpour, A; Vadivelu, J; Musa, S N; Kaboli, S H A

    2016-08-01

    PVD process as a thin film coating method is highly applicable for both metallic and ceramic materials, which is faced with the necessity of choosing the correct parameters to achieve optimal results. In the present study, a GEP-based model for the first time was proposed as a safe and accurate method to predict the adhesion strength and hardness of the Nb PVD coated aimed at growing the mixed oxide nanotubular arrays on Ti67. Here, the training and testing analysis were executed for both adhesion strength and hardness. The optimum parameter combination for the scratch adhesion strength and micro hardness was determined by the maximum mean S/N ratio, which was 350W, 20 sccm, and a DC bias of 90V. Results showed that the values calculated in the training and testing in GEP model were very close to the actual experiments designed by Taguchi. The as-sputtered Nb coating with highest adhesion strength and microhardness was electrochemically anodized at 20V for 4h. From the FESEM images and EDS results of the annealed sample, a thick layer of bone-like apatite was formed on the sample surface after soaking in SBF for 10 days, which can be connected to the development of a highly ordered nanotube arrays. This novel approach provides an outline for the future design of nanostructured coatings for a wide range of applications. Copyright © 2016 Elsevier Ltd. All rights reserved.

  8. Tribological properties of anti-wear PVD coatings for elevated temperatures application deposited onto X37CrMoV5-1 type hot work steel

    International Nuclear Information System (INIS)

    Dobrzanski, L.A.; Polok, M.; Adamiak, M.

    2003-01-01

    The paper presents results of tribological and adhesion investigations of anti-wear PVD coatings TiN, TiN/(Ti,Al)N and CrN types deposited in ion plating PVD process onto X37CrMoV5-1 type hot work tool steel. It was found that damage mechanism during scratch test in all investigated coatings begins with multiple spallings located on the scratch edges followed by cracking and tool coatings delamination. Regarding to the coating types it can be seen different location of such damages and loads typical for them. According to this observations it can be stated that highest adhesion among investigated coating present, CrN monolayer coating and the lowest one multilayers Ti/(Ti,Al)N coating. The wear resistance was investigated by pin-on-disc method performed in room and elevated to 500 o C temperatures. It was found that the lowest wear in to fixed investigation conditions in both room and elevated temperatures shows TiN monolayer coating. Additionally one can see that TiN coatings application improve wear resistance some five times. (author)

  9. ac impedance, DSC and FT-IR investigations on (x)PVAc-(1 - x)PVdF blends with LiClO4

    International Nuclear Information System (INIS)

    Baskaran, R.; Selvasekarapandian, S.; Kuwata, N.; Kawamura, J.; Hattori, T.

    2006-01-01

    The blended polymer electrolytes comprising poly(vinyl acetate) (PVAc)-poly(vinylidene fluoride) (PVdF) have been prepared for different blend composition with constant lithium perchlorate (LiClO 4 ) ratio by solution casting technique. The formation of the blend polymer electrolyte complex has been confirmed by FT-IR spectroscopy analysis. DSC analysis has been performed in order to observe the change in transition temperature that is caused by the blending of polymers and addition of LiClO 4 . The ac impedance and dielectric spectroscopy studies are carried out on the blended matrix to identify the optimized blend composition, which is having high ionic conductivity. The temperature dependence of conductivity of the polymer electrolytes is found to follow VTF type equation. The high ionic conductivity of 6.4 x 10 -4 S cm -1 at 343 K has been observed for blended polymer electrolyte having blend ratio 75:25 (PVAc:PVdF). The ionic transference number of mobile ions has been estimated by Wagner's polarization method and the value is reported to be t ion is 0.95-0.98 for all the blended samples. The modulus spectra reveal the non-Debye nature and distribution of relaxation times of the samples. The dielectric spectra show the low frequency dispersion, which implies the space charge effects arising from the electrodes

  10. Flexible free-standing TiO2/graphene/PVdF films as anode materials for lithium-ion batteries

    International Nuclear Information System (INIS)

    Ren, H.M.; Ding, Y.H.; Chang, F.H.; He, X.; Feng, J.Q.; Wang, C.F.; Jiang, Y.; Zhang, P.

    2012-01-01

    Highlights: ► Flexible TiO 2 /graphene electrode was prepared by a solvent evaporation technique. ► PVdF was used as substance to support the TiO 2 /graphene active materials. ► The flexible films can be employed as anode materials for Li-ion battery. - Abstract: Graphene composites were prepared by hydrothermal method using titanium dioxide (TiO 2 ) adsorbed graphene oxide (GO) sheets as precursors. Free-standing hybrid films for lithium-ion batteries were prepared by adding TiO 2 /graphene composites to the polyvinylidene fluoride (PVdF)/N-methyl-2-pyrrolidone (NMP) solution, followed by a solvent evaporation technique. These films were characterized by atomic force microscopy (AFM), X-ray diffraction (XRD), scanning electron microscopy (SEM) and various electrochemical techniques. Flexible films show an excellent cycling performance, which was attributed to the interconnected graphene conducting network, which depressed the increasing of electric resistance during the cycling.

  11. Development of nanostructured PVD coatings for total knee replacement joints using HIPIMS

    Science.gov (United States)

    Sugumaran, Arunprabhu A.

    The aim of this study was to develop thin film coatings for total knee replacement joints using high power impulse magnetron sputtering (HIPIMS). An industrial size four cathode magnetron sputtering system equipped with direct current (DC) and HIPIMS power supplies was used for this purpose. Initially, Plasma diagnostics were carried out using optical emission spectroscopy (OES) while sputtering Ti target in Ar + N2 atmosphere by utilizing various HIP IMS/conventional DCMS (henceforth UBM) source combinations by varying the process parameters such as coil current and N2 flow. Then, single layer titanium nitride (TiN) coating was deposited by varying the degree of HIPIMS utilisation and the process parameters such as bias voltage and coil current to thoroughly understand the effect of degree of HIPIMS utilisation on the microstructure, residual stress, texture, mechanical, tribological and corrosion properties of such coatings. The degree of HIPIMS utilisation was altered by increasing the number of HIPIMS targets used for the deposition. Four different source combinations were used for this purpose, as follows: 4 cathodes in conventional DCMS mode to deposit pure UBM coating, 1 HIPIMS + 3UBM and 2HIPIMS + 2UBM cathodes to deposit combined HIPIMS/UBM coatings and 2HIPIMS cathodes to deposit pure HIPIMS coatings. TiN/NbN, TiCN/NbCN and CrN/NbN multilayer coatings were deposited on CoCr alloy test buttons along with other (HSS, SS and Si) substrates since our intended application is on total knee replacement joints made of CoCr alloy. The knowledge gained by investigating the TiN (Ar + N[2]) plasma and the properties of TiN was used to determine the process parameters for depositing the multilayer coatings. X- ray diffraction (XRD) technique was used for calculating the texture, residual stress and bilayer thickness of the coatings. Nanoindentation method was used to determine the nano hardness of the coatings. The adhesion strength of the coatings was estimated by

  12. Variations of posterior vitreous detachment

    OpenAIRE

    Kakehashi, A.; Kado, M.; Akiba, J.; Hirokawa, H.

    1997-01-01

    AIMS—To identify variations in posterior vitreous detachment (PVD) and establish a clinical classification system for PVD.
METHODS—400 consecutive eyes were examined using biomicroscopy and vitreous photography and classified the PVD variations—complete PVD with collapse, complete PVD without collapse, partial PVD with thickened posterior vitreous cortex (TPVC), or partial PVD without TPVC.
RESULTS—In each PVD type, the most frequently seen ocular pathologies were as follows: in complete PVD ...

  13. System and method for mass production of graphene platelets in arc plasma

    Science.gov (United States)

    Keidar, Michael; Shashurin, Alexey

    2017-12-12

    A system and method for producing graphene includes a discharge assembly and a substrate assembly. The discharge assembly includes a cathode and an anode, which in one embodiment are offset from each other. The anode produces a flux stream that is deposited onto a substrate. A collection device removes the deposited material from the rotating substrate. The flux stream can be a carbon vapor, with the deposited flux being graphene.

  14. Characterization of the corrosion behavior of an austenitic stainless steel for biomedical applications coated with Ti N, Ti CN And DLC PVD coatings

    International Nuclear Information System (INIS)

    Antunes, Renato Altobelli

    2006-01-01

    Metallic biomaterials must present a combination of properties such as corrosion resistance, biocompatibility and mechanical resistance. Austenitic stainless steels, especially AISI 316L combine these properties with the easy of fabrication at low cost. However, they are prone to corrosion in physiological solutions. Furthermore, their corrosion products may lead to infectious ou allergenic reactions in the tissues around the implant device. In the present work, coatings produced by physical vapour deposition (PVD) methods have been applied on the surface of a 316L stainless steel to increase its corrosion resistance and biocompatibility. Three thin films were tested: titanium nitride (TiN), titanium carbonitride (TiCN) and diamond-like carbon (DLC). These materials present high hardness, wear resistance and intrinsic biocompatibility that are key features when considering biomedical applications. The characterization of the electrochemical behavior of the stainless steel coated with the three different films showed that the presence of surface defects are deleterious to the corrosion resistance of the substrate. These defects were observed using scanning electron microscopy. The evolution of the electrochemical behavior of the coated steel was explained through a mechanism based on the experimental results obtained using electrochemical impedance spectroscopy. Two different passivation treatments were carried out on the stainless steel surface, either in sulfuric or nitric acid solutions, to increase its corrosion resistance. The results suggested que these treatments were not efficient, but may be modified to improve its performance. The electronic properties of the passive films of the non-passivated and passivated stainless steel were studied using the Mott-Schottky approach. The films presented a duplex character. Below the flat band potential the behavior is typical of a highly doped type-p semiconductor. Above the flat band potential is typical of a highly

  15. Surface characteristics of hydroxyapatite-coated layer prepared on nanotubular Ti–35Ta–xHf alloys by EB-PVD

    Energy Technology Data Exchange (ETDEWEB)

    Jeong, Yong-Hoon [Department of Dental Materials and Research Center of Nano-Interface Activation for Biomaterials, School of Dentistry, Chosun University, Gwangju (Korea, Republic of); Biomechanics and Tissue Engineering Laboratory, Division of Orthodontics, College of Dentistry, The Ohio State University, Columbus, OH (United States); Moon, Byung-Hak [Department of Dental Materials and Research Center of Nano-Interface Activation for Biomaterials, School of Dentistry, Chosun University, Gwangju (Korea, Republic of); Choe, Han-Cheol, E-mail: hcchoe@chosun.ac.kr [Department of Dental Materials and Research Center of Nano-Interface Activation for Biomaterials, School of Dentistry, Chosun University, Gwangju (Korea, Republic of); Brantley, William A. [Division of Restorative, Prosthetic and Primary Care Dentistry, College of Dentistry, The Ohio State University, Columbus, OH (United States)

    2013-12-31

    In this study, we investigated the surface characteristics of hydroxyapatite (HA)-coated layers prepared by electron-beam physical vapor deposition (EB-PVD) on nanotubular Ti–35Ta–xHf alloys (x = 3, 7, and 15 wt.%). Ti–35Ta–xHf alloys were first prepared by arc melting. Formation of a nanotube structure on these alloys was achieved by an electrochemical method in 1 M H{sub 3}PO{sub 4} + 0.8 wt.% NaF electrolytes. The HA coatings were then deposited on the nanotubular surface by an EB-PVD method. The surface characteristics were analyzed by field-emission scanning electron microscopy, energy-dispersive X-ray spectroscopy, and X-ray diffraction (XRD). The electrochemical behavior was examined using a potentiodynamic polarization test in 0.9% NaCl solution. The Ti–35Ta–xHf alloys had an equiaxed grain structure with α″ + β phases, and the α″ phase disappeared with increases in Hf content. The Ti–35Ta–15Hf alloy showed higher β-phase peak intensity in the XRD patterns than that for the lower Hf-content alloys. A highly ordered nanotubular oxide layer was formed on the Ti–35Ta–15Hf alloy, and the tube length depended on Hf content. The HA coating surface formed at traces of the nanotubular titanium oxide layer and completely covered the tips of the nanotubes with a cluster shape. From the potentiodynamic polarization tests, the incorporation of Hf element and formation of the nanotubular structure were the main factors for achieving lower current density. In particular, the surface of the HA coating on the nanotubular structure exhibited higher corrosion resistance than that of the nanotubular titanium oxide structure without an HA coating. - Highlights: • Hydroxyapatite (HA) was coated on nanotubular Ti–35Ta–xHf alloys, using EB-PVD. • Increasing the Hf content reduced the relative proportion of α″ martensite to β-Ti in the microstructures. • The detailed nanotubular structure formed by anodization depended on alloy composition

  16. Surface characteristics of hydroxyapatite-coated layer prepared on nanotubular Ti–35Ta–xHf alloys by EB-PVD

    International Nuclear Information System (INIS)

    Jeong, Yong-Hoon; Moon, Byung-Hak; Choe, Han-Cheol; Brantley, William A.

    2013-01-01

    In this study, we investigated the surface characteristics of hydroxyapatite (HA)-coated layers prepared by electron-beam physical vapor deposition (EB-PVD) on nanotubular Ti–35Ta–xHf alloys (x = 3, 7, and 15 wt.%). Ti–35Ta–xHf alloys were first prepared by arc melting. Formation of a nanotube structure on these alloys was achieved by an electrochemical method in 1 M H 3 PO 4 + 0.8 wt.% NaF electrolytes. The HA coatings were then deposited on the nanotubular surface by an EB-PVD method. The surface characteristics were analyzed by field-emission scanning electron microscopy, energy-dispersive X-ray spectroscopy, and X-ray diffraction (XRD). The electrochemical behavior was examined using a potentiodynamic polarization test in 0.9% NaCl solution. The Ti–35Ta–xHf alloys had an equiaxed grain structure with α″ + β phases, and the α″ phase disappeared with increases in Hf content. The Ti–35Ta–15Hf alloy showed higher β-phase peak intensity in the XRD patterns than that for the lower Hf-content alloys. A highly ordered nanotubular oxide layer was formed on the Ti–35Ta–15Hf alloy, and the tube length depended on Hf content. The HA coating surface formed at traces of the nanotubular titanium oxide layer and completely covered the tips of the nanotubes with a cluster shape. From the potentiodynamic polarization tests, the incorporation of Hf element and formation of the nanotubular structure were the main factors for achieving lower current density. In particular, the surface of the HA coating on the nanotubular structure exhibited higher corrosion resistance than that of the nanotubular titanium oxide structure without an HA coating. - Highlights: • Hydroxyapatite (HA) was coated on nanotubular Ti–35Ta–xHf alloys, using EB-PVD. • Increasing the Hf content reduced the relative proportion of α″ martensite to β-Ti in the microstructures. • The detailed nanotubular structure formed by anodization depended on alloy composition. • The

  17. Improvement in ductility of high strength polycrystalline Ni-rich Ni{sub 3}Al alloy produced by EB-PVD

    Energy Technology Data Exchange (ETDEWEB)

    Sun, J.Y.; Pei, Y.L.; Li, S.S.; Zhang, H.; Gong, S.K., E-mail: gongsk@buaa.edu.cn

    2014-11-25

    Highlights: • High strength and high ductility of polycrystalline Ni-rich Ni{sub 3}Al alloy sheets were produced. • The elongation could be enhanced from ∼0.5% to ∼14.6% by microstructural control. • The fracture strength (∼820 MPa) was enhanced by the precipitation strengthening. • This work provides a general processing for repairing the worn single crystal blades. - Abstract: A 300 μm Ni-rich Ni{sub 3}Al sheet was produced by electron beam physical vapor deposition (EB-PVD) and followed by different heat treatments to obtain fine γ′/γ two-phase structures with large elongation. Tensile testing was performed at room-temperature, and the corresponding mechanisms were investigated in detail. Results indicated that the as-deposited Ni{sub 3}Al alloy exhibited non-equilibrium directional columnar crystal, and transited to equiaxed crystal with uniformly distributed tough γ phase after heat treatment. Meanwhile, the fracture mechanism transited from brittleness to a mixture of ductility and brittleness modes. With an appropriate heat treatment, high strength (ultimate tensile strength obtained 828 MPa) and high ductility (elongation obtained 14.6%) Ni{sub 3}Al alloy has been achieved, which was due to the mesh network microstructure. A series of transmission electron microscope (TEM) characterizations confirmed that the increasing flow stress of Ni{sub 3}Al alloy was attributed to the cubical secondary γ′ phase precipitates (25–50 nm) within the γ phase. This work provides a potential strategy for repairing the worn tip of single crystal engine blades using Ni-rich Ni{sub 3}Al alloy by EB-PVD.

  18. Plasma-Enhanced Chemical Vapor Deposition (PE-CVD) yields better Hydrolytical Stability of Biocompatible SiOx Thin Films on Implant Alumina Ceramics compared to Rapid Thermal Evaporation Physical Vapor Deposition (PVD).

    Science.gov (United States)

    Böke, Frederik; Giner, Ignacio; Keller, Adrian; Grundmeier, Guido; Fischer, Horst

    2016-07-20

    Densely sintered aluminum oxide (α-Al2O3) is chemically and biologically inert. To improve the interaction with biomolecules and cells, its surface has to be modified prior to use in biomedical applications. In this study, we compared two deposition techniques for adhesion promoting SiOx films to facilitate the coupling of stable organosilane monolayers on monolithic α-alumina; physical vapor deposition (PVD) by thermal evaporation and plasma enhanced chemical vapor deposition (PE-CVD). We also investigated the influence of etching on the formation of silanol surface groups using hydrogen peroxide and sulfuric acid solutions. The film characteristics, that is, surface morphology and surface chemistry, as well as the film stability and its adhesion properties under accelerated aging conditions were characterized by means of X-ray photoelectron spectroscopy (XPS), energy dispersive X-ray spectroscopy (EDX), scanning electron microscopy (SEM), inductively coupled plasma-optical emission spectroscopy (ICP-OES), and tensile strength tests. Differences in surface functionalization were investigated via two model organosilanes as well as the cell-cytotoxicity and viability on murine fibroblasts and human mesenchymal stromal cells (hMSC). We found that both SiOx interfaces did not affect the cell viability of both cell types. No significant differences between both films with regard to their interfacial tensile strength were detected, although failure mode analyses revealed a higher interfacial stability of the PE-CVD films compared to the PVD films. Twenty-eight day exposure to simulated body fluid (SBF) at 37 °C revealed a partial delamination of the thermally deposited PVD films whereas the PE-CVD films stayed largely intact. SiOx layers deposited by both PVD and PE-CVD may thus serve as viable adhesion-promoters for subsequent organosilane coupling agent binding to α-alumina. However, PE-CVD appears to be favorable for long-term direct film exposure to aqueous

  19. Determination of the fatigue properties of multilayer PVD coatings on various substrates, based on the impact test and its FEM simulation

    Energy Technology Data Exchange (ETDEWEB)

    Bouzakis, K.D.; Vidakis, N. [Aristotle Univ., Thessaloniki (Greece). Dept. of Mech. Eng.; Leyendecker, T.; Erkens, G.; Wenke, R.

    1997-10-31

    The coating impact test, in combination with its finite elements method (FEM) simulation, is used to quantitatively characterize the fatigue behaviour of thin hard physical vapour deposited (PVD) coatings as well as of multilayer ones. Successive impacts of a cemented carbide ball onto a plane coated specimen induce severe contact loads and strain superficially the layered compound. The fatigue failure mode of each specimen is classified by means of scanning electron microscope (SEM) observations, microspectral analyses and profilometry. FEM simulating models of the impact test are used to determine the critical stress components, which introduce coating fatigue failure. The FEM computational results are correlated to the experimental ones and used to interpret them quantitatively. Herewith, critical values for stress components, responsible for distinctive fatigue failure modes of the coating substrate compounds are obtained and the fatigue limits of the examined multilayer coatings are inserted in general applicable Smith diagrams. Furthermore, the derived critical stresses are verified by investigating the same multilayer coatings on different substrates. (orig.) 14 refs.

  20. Application of response surface methodology on investigating flank wear in machining hardened steel using PVD TiN coated mixed ceramic insert

    Directory of Open Access Journals (Sweden)

    Ashok Kumar Sahoo

    2013-10-01

    Full Text Available The paper presents the development of flank wear model in turning hardened EN 24 steel with PVD TiN coated mixed ceramic insert under dry environment. The paper also investigates the effect of process parameter on flank wear (VBc. The experiments have been conducted using three level full factorial design techniques. The machinability model has been developed in terms of cutting speed (v, feed (f and machining time (t as input variable using response surface methodology. The adequacy of model has been checked using correlation coefficients. As the determination coefficient, R2 (98% is higher for the model developed; the better is the response model fits the actual data. In addition, residuals of the normal probability plot lie reasonably close to a straight line showing that the terms mentioned in the model are statistically significant. The predicted flank wear has been found to lie close to the experimental value. This indicates that the developed model can be effectively used to predict the flank wear in the hard turning. Abrasion and diffusion has been found to be the dominant wear mechanism in machining hardened steel from SEM micrographs at highest parametric range. Machining time has been found to be the most significant parameter on flank wear followed by cutting speed and feed as observed from main effect plot and ANOVA study.

  1. Improvement of Wear Performance of Nano-Multilayer PVD Coatings under Dry Hard End Milling Conditions Based on Their Architectural Development

    Directory of Open Access Journals (Sweden)

    Shahereen Chowdhury

    2018-02-01

    Full Text Available The TiAlCrSiYN-based family of PVD (physical vapor deposition hard coatings was specially designed for extreme conditions involving the dry ultra-performance machining of hardened tool steels. However, there is a strong potential for further advances in the wear performance of the coatings through improvements in their architecture. A few different coating architectures (monolayer, multilayer, bi-multilayer, bi-multilayer with increased number of alternating nano-layers were studied in relation to cutting-tool life. Comprehensive characterization of the structure and properties of the coatings has been performed using XRD, SEM, TEM, micro-mechanical studies and tool-life evaluation. The wear performance was then related to the ability of the coating layer to exhibit minimal surface damage under operation, which is directly associated with the various micro-mechanical characteristics (such as hardness, elastic modulus and related characteristics; nano-impact; scratch test-based characteristics. The results presented exhibited that a substantial increase in tool life as well as improvement of the mechanical properties could be achieved through the architectural development of the coatings.

  2. Structural and Mechanical Properties of the ZrC/Ni-Nanodiamond Coating Synthesized by the PVD and Electroplating Processes for the Cutting Knifes

    Science.gov (United States)

    Chayeuski, V.; Zhylinski, V.; Cernashejus, O.; Visniakov, N.; Mikalauskas, G.

    2018-04-01

    In this work, combined gradient ZrC/Ni-nanodiamond ultradispersed diamonds (UDD) coatings were synthesized on the surface of knife blades made of hard alloy WC-2 wt.% Co by electroplating and cathode arc evaporation PVD techniques to increase the durability period of a wood-cutting milling tool. The microstructure, phase and elemental composition, microhardness, and adhesion strength of the coatings were investigated. Ni-UDD layer is not mixed with the ZrC coating and hard alloy substrate. Cobalt is present in Ni-UDD layer after deposition of ZrC. The ZrC/Ni-nanodiamond coating consists of separate phases of zirconium carbide (ZrC), α-Ni, and Ni-UDD. The maximum value of microhardness of the Ni-nanodiamond coating is 5.9 GPa. The microhardness value of the ZrC/Ni-nanodiamond coatings is 25 ± 6 GPa, which corresponds to the microhardness of the hard alloy substrate and ZrC coating. The obtained high values of the critical loads on the scratch track of the ZrC/Ni-nanodiamond coating in 24 N prove a sufficiently high value of the adhesion strength of the bottom Ni-UDD layer with WC-Co substrate. Pilot testing of ZrC/Ni-nanodiamond-coated cutting tools proved their increasing durability period to be 1.5-1.6 times higher than that of bare tools, when milling laminated chipboard.

  3. On the application of response surface methodology for predicting and optimizing surface roughness and cutting forces in hard turning by PVD coated insert

    Directory of Open Access Journals (Sweden)

    Hessainia Zahia

    2015-04-01

    Full Text Available This paper focuses on the exploitation of the response surface methodology (RSM to determine optimum cutting conditions leading to minimum surface roughness and cutting force components. The technique of RSM helps to create an efficient statistical model for studying the evolution of surface roughness and cutting forces according to cutting parameters: cutting speed, feed rate and depth of cut. For this purpose, turning tests of hardened steel alloy (AISI 4140 (56 HRC were carried out using PVD – coated ceramic insert under different cutting conditions. The equations of surface roughness and cutting forces were achieved by using the experimental data and the technique of the analysis of variance (ANOVA. The obtained results are presented in terms of mean values and confidence levels. It is shown that feed rate and depth of cut are the most influential factors on surface roughness and cutting forces, respectively. In addition, it is underlined that the surface roughness is mainly related to the cutting speed, whereas depth of cut has the greatest effect on the evolution of cutting forces. The optimal machining parameters obtained in this study represent reductions about 6.88%, 3.65%, 19.05% in cutting force components (Fa, Fr, Ft, respectively. The latters are compared with the results of initial cutting parameters for machining AISI 4140 steel in the hard turning process.

  4. Embedded layer of Ag nanoparticles prepared by a combined PECVD/PVD process producing SiOxCy-Ag nanocomposite thin films.

    Science.gov (United States)

    Bedel, Laurent; Cayron, Cyril; Jouve, Michel; Maury, Francis

    2012-01-13

    Structural properties of SiO(x)C(y)-Ag nanocomposite thin films prepared by a dual process PVD-PECVD in the same reactor have been investigated. The experimental results have demonstrated the influence of a PECVD process carried out at room temperature for the growth of a dielectric matrix on the size and the distribution density of Ag nanoparticles (NPs) deposited beforehand by magnetron sputtering. The plasma during the growth of the encapsulation SiO(x)C(y) layer caused a diffusion of silver from NPs through the SiO(x)C(y) matrix associated with a decrease in the average size of nanoparticles and an increase of their distribution density. Silver diffusion is blocked at a barrier interface to form a buried layer of individual Ag NPs which, for instance, can find plasmonic applications. Silver also diffuses toward the outer surface inducing antibacterial properties. In both cases initial Ag NPs act as reservoirs for multifunctional properties of advanced nanostructured films.

  5. Effect of La2O3 addition on interface chemistry between 4YSZ top layer and Ni based alloy bond coat in thermal barrier coating by EB PVD.

    Science.gov (United States)

    Park, Chan-Young; Yang, Young-Hwan; Kim, Seong-Won; Lee, Sung-Min; Kim, Hyung-Tae; Jang, Byung-Koog; Lim, Dae-Soon; Oh, Yoon-Suk

    2014-11-01

    The effect of a 5 mol% La2O3 addition on the forming behavior and compositional variation at interface between a 4 mol% Yttria (Y2O3) stabilized ZrO2 (4YSZ) top coat and bond coat (NiCrAlY) as a thermal barrier coating (TBC) has been investigated. Top coats were deposited by electron beam physical vapor deposition (EB PVD) onto a super alloy (Ni-Cr-Co-Al) substrate without pre-oxidation of the bond coat. Top coats are found to consist of dense columnar grains with a thin interdiffusion layer between metallic bond coats. In the as-received 4YSZ coating, a thin interdiffusion zone at the interface between the top and bond coats was found to consist of a Ni-Zr intermetallic compound with a reduced quantity of Y, Al or O elements. On the other hand, in the case of an interdiffusion area of 5 mol% La2O3-added 4YSZ coating, it was found that the complicated composition and structure with La-added YSZ and Ni-Al rich compounds separately. The thermal conductivity of 5 mol% La2O3-added 4YSZ coating (- 1.6 W/m x k at 1100 degrees C) was lower than a 4YSZ coating (- 3.2 W/m x k at 1100 degrees C) alone.

  6. Effect of a ductility layer on the tensile strength of TiAl-based multilayer composite sheets prepared by EB-PVD

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Rubing, E-mail: zrb86411680@126.com [Department of Mechanics, School of Civil Engineering, Beijing Jiaotong University, Beijing 100044 (China); Zhang, Yaoyao [Department of Mechanics, School of Civil Engineering, Beijing Jiaotong University, Beijing 100044 (China); Liu, Qiang [Beijing Institute of Astronautical Systems Engineering, Beijing 100076 (China); Chen, Guiqing [Center for Composite Materials, Harbin Institute of Technology, Harbin 150001 (China); Zhang, Deming [Beijing General Research Institute of Mining and Metallurgy, Beijing 100044 (China)

    2014-09-15

    TiAl/Nb and TiAl/NiCoCrAl laminate composite sheets with a thickness of 0.4–0.6 mm and dimensions of 150 mm × 100 mm were successfully fabricated by electron beam physical vapor deposition. The microstructures of the sheets were examined, and their mechanical properties were compared with those of TiAl monolithic sheet produced by electron beam physical vapor deposition. Tensile testing was performed at room temperature and 750 °C, and the fracture surfaces were examined by scanning electron microscopy. Among the three microlaminate sheets, the TiAl/NiCoCrAl micro-laminate sheet had the best comprehensive properties at room temperature, and the TiAl/Nb micro-laminate sheet showed the ideal high-temperature strength and plasticity at 750 °C. The result was discussed in terms of metal strengthening mechanism. - Highlights: • TiAl-based multilayer foils was fabricated successfully by using EB-PVD method; • The tensile properties and micro-fracture morphologies of the sheet were investigated; • The deformation behavior of the multilayer foils was discussed.

  7. Formation of semi-IPN membrane composed of crosslinked SPS-[PVdF-co-HFP/Nafion] for application in DMFC: A fine tuning between crosslinker and initiator

    Energy Technology Data Exchange (ETDEWEB)

    Kumar, Piyush; Kundu, Patit Paban, E-mail: ppk923@yahoo.com

    2015-08-15

    The semi-interpenetrating (semi-IPN) membrane composed of crosslinked sulfonated polystyrene (SPS) within the host blend of PVdF-co-HFP (Polyvinylidenefluoride-co-hexafluoropropylene) and Nafion has already been tested as a promising polymer electrolyte membrane (PEM) in terms of improved water uptake, proton conductivity and electrical efficiency for application in the direct methanol fuel cell (DMFC). These desired results have generated further curiosity about a fine tuning between the contents of divinyl benzene (DVB) as a crosslinker and azobisisobutyronitrile (AIBN) as an initiator for the optimization of PEM characteristics. It has been observed that an increase in AIBN content leads to an acceptable degree of water uptake, swelling ratio and proton conductivity in PEM, while higher DVB content causes declined methanol crossover, leading to higher membrane selectivity. These two opposing effects are optimized in terms of proton conductivity, tensile strength and membrane selectivity for the membrane consisting of 0.4 wt% of AIBN and 1.2 wt% of DVB. Moreover, the maximum power density obtained for the membrane having optimum selectivity is 56 mW cm{sup −2}, when analyzed at 90 °C. These results indicate that one can achieve a high power density in comparison to Nafion by fine tuning the contents of initiator and cross-linker during the synthesis of the semi-IPN membrane. - Graphical abstract: Display Omitted - Highlights: • PEM composed of 0.4/1.2 wt% of AIBN/DVB produced best result. • Lower methanol crossover (1.02 × 10{sup −6} cm{sup 2} s{sup −1}) compare to Nafion-117. • Higher membrane selectivity i.e 3.05 × 10{sup 4} Ss cm{sup −3} was obtained. • A maximum power density of 56 mW cm{sup −2} was obtained at 90 °C.

  8. Formation of semi-IPN membrane composed of crosslinked SPS-[PVdF-co-HFP/Nafion] for application in DMFC: A fine tuning between crosslinker and initiator

    International Nuclear Information System (INIS)

    Kumar, Piyush; Kundu, Patit Paban

    2015-01-01

    The semi-interpenetrating (semi-IPN) membrane composed of crosslinked sulfonated polystyrene (SPS) within the host blend of PVdF-co-HFP (Polyvinylidenefluoride-co-hexafluoropropylene) and Nafion has already been tested as a promising polymer electrolyte membrane (PEM) in terms of improved water uptake, proton conductivity and electrical efficiency for application in the direct methanol fuel cell (DMFC). These desired results have generated further curiosity about a fine tuning between the contents of divinyl benzene (DVB) as a crosslinker and azobisisobutyronitrile (AIBN) as an initiator for the optimization of PEM characteristics. It has been observed that an increase in AIBN content leads to an acceptable degree of water uptake, swelling ratio and proton conductivity in PEM, while higher DVB content causes declined methanol crossover, leading to higher membrane selectivity. These two opposing effects are optimized in terms of proton conductivity, tensile strength and membrane selectivity for the membrane consisting of 0.4 wt% of AIBN and 1.2 wt% of DVB. Moreover, the maximum power density obtained for the membrane having optimum selectivity is 56 mW cm −2 , when analyzed at 90 °C. These results indicate that one can achieve a high power density in comparison to Nafion by fine tuning the contents of initiator and cross-linker during the synthesis of the semi-IPN membrane. - Graphical abstract: Display Omitted - Highlights: • PEM composed of 0.4/1.2 wt% of AIBN/DVB produced best result. • Lower methanol crossover (1.02 × 10 −6 cm 2 s −1 ) compare to Nafion-117. • Higher membrane selectivity i.e 3.05 × 10 4 Ss cm −3 was obtained. • A maximum power density of 56 mW cm −2 was obtained at 90 °C

  9. Al_2O_3/PVdF-HFP-CMC/PE separator prepared using aqueous slurry and post-hot-pressing method for polymer lithium-ion batteries with enhanced safety

    International Nuclear Information System (INIS)

    Deng, Yaoming; Song, Xiaona; Ma, Zhen; Zhang, Xinhe; Shu, Dong; Nan, Junmin

    2016-01-01

    A composite separator is prepared to improve the safety of lithium ion batteries (LIBs) based on a gravure coating aqueous slurry and post-hot-pressing method. An environmentally friendly aqueous slurry with an Al_2O_3 ceramic holder and polyvinylidene difluoride-hexafluoropropylene (PVdF-HFP) and carboxymethyl cellulose (CMC) dual-binders is coated on a polyolefin (PE) substrate to form a prototype Al-PHC/PE separator. Then, after assembling the separator in the batteries and hot-pressing at 70 °C and 0.8 MPa for 3 h, the granular PVdF-HFP is transformed into a colloidal structure containing an electrolyte, which can binds the Al_2O_3 nanoparticles together and increases the battery hardness. Compared with a PE separator (9 μm), the Al-PHC/PE-2 separator (12 μm, with a Al_2O_3/PVdF-HFP weight ratio of 7/3) displays a comparative ionic conductivity of 9.3 × 10"−"4 S cm"−"2 and exhibits no obvious thermal deformation at 110 °C for 60 min. All of the batteries assembled with Al-PHC/PE-2 separators passed nail penetration and impact tests. In addition, the capacity retention increases from 83.4% to 87.6% when the battery is assembled with Al-PHC/PE-2 instead of a PE separator and charge-discharged at 0.7C/1.0C for 350 cycles. The enhanced safety and cycle performance indicate the promising prospect of Al-PHC/PE separators in LIBs.

  10. Cryogenic thermal storage system for discontinuous industrial vacuum processes

    Directory of Open Access Journals (Sweden)

    Scaringella M.

    2012-10-01

    Full Text Available Phase Change Materials are proposed for refrigerating systems in discontinuous industrial vacuum processes where temperatures as low as −140 ÷ −100°C are necessary within time-frames representing 10÷20% of total operating time. An application is proposed for cooling systems used in a Physical Vapour Deposition (PVD apparatus. A prototype has been manufactured which couples a cryopump with a reservoir filled with MethylCycloPentane (MCP-C6H12 and a distribution line where nitrogen in the gaseous state is flowing. Preliminary tests show that temperatures of about −120°C are actually achieved within time windows compatible with PVD applications.

  11. Surface and interface analysis of PVD Al-O-N and {gamma}-Al{sub 2}O{sub 3} diffusion barriers

    Energy Technology Data Exchange (ETDEWEB)

    Cremer, R.; Witthaut, M.; Reichert, K.; Neuschuetz, D. [Technische Hochschule Aachen (Germany). Lehrstuhl fuer Metallurgie der Kernbrennstoffe und Theoretische Huettenkunde

    1999-10-01

    The suitability of PVD films of {gamma}-Al{sub 2}O{sub 3} and of ternary Al-O-N as diffusion barriers between a nickel based superalloy CMSX-4 and NiCoCrAlY for a possible application in gas turbines was investigated. Therefore, an Al{sub 2}O{sub 3} film and, alternatively, an Al-O-N film were deposited on CMSX-4 at 100 C substrate temperature by means of reactive magnetron sputtering ion plating (MSIP). After characterization of composition and structure of the films by X-ray photoelectron spectroscopy (XPS) and grazing incidence X-ray diffraction (XRD), a NiCoCrAlY coating was deposited onto the diffusion barriers and, for comparison, directly onto CMSX-4 by MSIP as well. The composites were annealed for 4 h at 1100 C under inert atmosphere. Wavelength dispersive X-ray (WDX) element mappings and line-scans of the cross-sectional cut served to evaluate the suitability of the films as diffusion barriers. After detachment of the coatings from the substrate, the phase stabilities of the two metastable phases {gamma}-Al{sub 2}O{sub 3} and Al-O-N were determined by means of grazing incidence XRD. Without a diffusion barrier, enhanced interdiffusion was observed. Analyses of the composite with the {gamma}-Al{sub 2}O{sub 3} interlayer revealed diffusion of Ti and Ta from the substrate into the NiCoCrAlY coating. No interdiffusion of Ni, Ti, Ta, and Cr could be detected in case of the ternary Al-O-N film. Whereas the ternary Al-O-N film remained in the as-deposited X-ray amorphous structure after annealing, a phase change from the {gamma} to the {alpha} modification could be observed in case of the Al{sub 2}O{sub 3} film, presumably responsible for its lower efficiency as a diffusion barrier. (orig.)

  12. Corrosion Resistance Behavior of Single-Layer Cathodic Arc PVD Nitride-Base Coatings in 1M HCl and 3.5 pct NaCl Solutions

    Science.gov (United States)

    Adesina, Akeem Yusuf; Gasem, Zuhair M.; Madhan Kumar, Arumugam

    2017-04-01

    The electrochemical behavior of single-layer TiN, CrN, CrAlN, and TiAlN coatings on 304 stainless steel substrate, deposited using state-of-the-art and industrial size cathodic arc PVD machine, were evaluated in 1M HCl and 3.5 pct NaCl solutions. The corrosion behavior of the blank and coated substrates was analyzed by electrochemical impedance spectroscopy (EIS), linear polarization resistance, and potentiodynamic polarization. Bond-coat layers of pure-Ti, pure-Cr, alloyed-CrAl, and alloyed-TiAl for TiN, CrN, CrAlN, and TiAlN coatings were, respectively, first deposited for improved coating adhesion before the actual coating. The average coating thickness was about 1.80 µm. Results showed that the corrosion potentials ( E corr) of the coated substrates were shifted to more noble values which indicated improvement of the coated substrate resistance to corrosion susceptibility. The corrosion current densities were lower for all coated substrates as compared to the blank substrate. Similarly, EIS parameters showed that these coatings possessed improved resistance to defects and pores in similar solution compared to the same nitride coatings developed by magnetron sputtering. The charge transfer resistance ( R ct) can be ranked in the following order: TiAlN > CrN > TiN > CrAlN in both media except in NaCl solution where R ct of TiN is lowest. While the pore resistance ( R po) followed the order: CrAlN > CrN > TiAlN > TiN in HCl solution and TiAlN > CrN > CrAlN > TiN in NaCl solution. It is found that TiAlN coating has the highest protective efficiencies of 79 and 99 pct in 1M HCl and 3.5 pct NaCl, respectively. SEM analysis of the corroded substrates in both media was also presented.

  13. Experimental and numerical investigations on the temperature distribution in PVD AlTiN coated and uncoated Al2O3/TiCN mixed ceramic cutting tools in hard turning of AISI 52100 steel

    Science.gov (United States)

    Sateesh Kumar, Ch; Patel, Saroj Kumar; Das, Anshuman

    2018-03-01

    Temperature generation in cutting tools is one of the major causes of tool failure especially during hard machining where machining forces are quite high resulting in elevated temperatures. Thus, the present work investigates the temperature generation during hard machining of AISI 52100 steel (62 HRC hardness) with uncoated and PVD AlTiN coated Al2O3/TiCN mixed ceramic cutting tools. The experiments were performed on a heavy duty lathe machine with both coated and uncoated cutting tools under dry cutting environment. The temperature of the cutting zone was measured using an infrared thermometer and a finite element model has been adopted to predict the temperature distribution in cutting tools during machining for comparative assessment with the measured temperature. The experimental and numerical results revealed a significant reduction of cutting zone temperature during machining with PVD AlTiN coated cutting tools when compared to uncoated cutting tools during each experimental run. The main reason for decrease in temperature for AlTiN coated tools is the lower coefficient of friction offered by the coating material which allows the free flow of the chips on the rake surface when compared with uncoated cutting tools. Further, the superior wear behaviour of AlTiN coating resulted in reduction of cutting temperature.

  14. [PVD-silicoating before cementation of zirconia-based knee prostheses effects better cement adhesion and lower aseptic loosening rates].

    Science.gov (United States)

    Marx, R; Faramarzi, R; Oberbach, T; Begand, S; Grätz, N; Wirtz, D C

    2012-02-01

    stable for blasted and silicate-layered compared with "as fired" ATZ samples. Silicoating may be effective for achieving a high initial bond strength of bone cement on surfaces of oxide ceramics and also suitable to stabilise bond strength under hydrolytic conditions as present in the human body. Activation by low grain size corundum (mean grain size 50 µm) seems to be effective for activation without deteriorating the bending strength of the ceramics investigated. Due to the proposed layer system migration, micromotions and debonding should be widely reduced or even eliminated. © Georg Thieme Verlag KG Stuttgart · New York.

  15. Process-structure-property relationships of micron thick gadolinium oxide films deposited by reactive electron beam-physical vapor deposition (EB-PVD)

    Science.gov (United States)

    Grave, Daniel A.

    Gadolinium oxide (Gd2O3) is an attractive material for solid state neutron detection due to gadolinium's high thermal neutron capture cross section. Development of neutron detectors based on Gd2 O3 requires sufficiently thick films to ensure neutron absorption. In this dissertation work, the process-structure-property relationships of micron thick Gd2O3 films deposited by reactive electron-beam physical vapor deposition (EB-PVD) were studied. Through a systematic design of experiments, fundamental studies were conducted to determine the effects of processing conditions such as deposition temperature, oxygen flow rate, deposition rate, and substrate material on Gd2O3 film crystallographic phase, texture, morphology, grain size, density, and surface roughness. Films deposited at high rates (> 5 A/s) were examined via x-ray diffraction (XRD) and Raman spectroscopy. Quantitative phase volume calculations were performed via a Rietveld refinement technique. All films deposited at high rates were found to be fully monoclinic or mixed cubic/monoclinic phase. Generally, increased deposition temperature and increased oxygen flow resulted in increased cubic phase volume. As film thickness increased, monoclinic phase volume increased. Grazing incidence x-ray diffraction (GIXRD) depth profiling analysis showed that cubic phase was only present under large incidence angle (large penetration depth) measurements, and after a certain point, only monoclinic phase was grown. This was confirmed by transmission electron microscopy (TEM) analysis with selected area diffraction (SAD). Based on this information, a large compressive stress was hypothesized to cause the formation of the monoclinic phase and this hypothesis was confirmed by demonstrating the existence of a stress induced phase transition. An experiment was designed to introduce compressive stress into the Gd2O 3 films via ion beam assisted deposition (IBAD). This allowed for systematic increase in compressive stress while

  16. Corrosion behaviour in saline environments of single-layer titanium and aluminium coatings, and of Ti/Al alternated multi-layers elaborated by a multi-beam PVD technique

    International Nuclear Information System (INIS)

    Merati, Abdenacer

    1994-01-01

    This research thesis reports the characterization of anti-corrosion titanium and aluminium coatings deposited on a 35CD4 steel under the form of mono-metallic layers or alternated Ti/Al multi-layers, and obtained by a multibeam PVD technique. The influence of different parameters is studied: single-layer thickness (5, 15 or 30 micro-metres), multi-layer distribution (5 to 6) and substrate (smooth or threaded). Layer nature and microstructure are studied by optical microscopy and scanning electron microscopy (SEM), as well as corrosion toughness in aqueous saline environments. Coated threaded samples have been studied after tightening tests. It appears that titanium layers are denser and more uniform than aluminium layers, and that multi-layer coatings provide a better protection than single-layer coatings. The best behaviour is obtained when titanium is in contact with steel, and aluminium is the outer layer in contact with the corroding environment [fr

  17. DEFORMACIÓN ELÁSTICA RESIDUAL EN LÁMINAS DE ACERO AISI 304 RECUBIERTAS CON UNA PELÍCULA DE NITRURO DE TITANIO DEPOSITADA POR PVD-MAGNETRON SPUTTERING

    Directory of Open Access Journals (Sweden)

    H. A. COLORADO

    2009-01-01

    Full Text Available Se realizó una caracterización mediante difracción de rayos x (DRX en láminas de acero inoxidable AISI 304 recubierto con una capa de nitruro de titanio de 3 um de espesor, obtenida mediante deposición física de vapor (PVD-MAGNETRON SPUTTERING a una temperatura de 200 °C. se tomaron imágenes de microscopía electrónica de barrido (MEB, microscopía óptica (MO y microscopía de fuerza atómica (MFA para caracterizar el sustrato, la capa y la zona cercana a la intercara. adicionalmente se determinó la deformación elástica residual asociada con el ensanchamiento de los picos de DRX.

  18. Thermal cycling behavior of La{sub 2}Zr{sub 2}O{sub 7} coating with the addition of Y{sub 2}O{sub 3} by EB-PVD

    Energy Technology Data Exchange (ETDEWEB)

    Xu Zhenhua [State Key Laboratory of Rare Earth Resources Utilization, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun 130022 (China); Graduate School of Chinese Academy of Sciences, Beijing 100039 (China); Beijing Institute of Aeronautical Materials, Department 5, P.O. Box 81-5, Beijing 100095 (China); He Limin, E-mail: he_limin@yahoo.co [Beijing Institute of Aeronautical Materials, Department 5, P.O. Box 81-5, Beijing 100095 (China); Chen Xiaolong; Zhao Yu [State Key Laboratory of Rare Earth Resources Utilization, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun 130022 (China); Mu Rende; He Shimei [Beijing Institute of Aeronautical Materials, Department 5, P.O. Box 81-5, Beijing 100095 (China); Cao Xueqiang, E-mail: xcao@ciac.jl.c [State Key Laboratory of Rare Earth Resources Utilization, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun 130022 (China)

    2010-10-15

    Thermal barrier coatings (TBCs) of La{sub 2}Zr{sub 2}O{sub 7} (LZ) with the addition of 3 wt.% Y{sub 2}O{sub 3} (LZ3Y) were deposited by electron beam-physical vapor deposition (EB-PVD). The phase structures, surface and cross-sectional morphologies, cyclic oxidation behaviors of these coatings were studied in detail. The thermal cycling test at 1373 K in an air furnace indicates that the LZ3Y coating has a lifetime of 617 cycles which is about 10% longer than that of LZ coating. The improvement of chemical homogeneity of the coating, the superior growth behavior of columns and the favorable mechanical properties are all very helpful to the prolongation of thermal cycling life of LZ3Y coating. The failure of LZ and LZ3Y coatings is mainly a result of the excess La{sub 2}O{sub 3}, the chemical incompatibility of ceramic coatings with TGO layer, the thermal expansion mismatch between ceramic coatings and bond coat, and the outward diffusion of alloying elements into the ceramic coatings.

  19. Decontamination Systems Information and Reseach Program

    Energy Technology Data Exchange (ETDEWEB)

    Cook, Echol E

    1998-04-01

    The following paragraphs comprise the research efforts during the first quarter of 1998 (January 1 - March 31). These tasks have been granted a continuation from the 1997 work and will all end in June 1998. This report represents the last technical quarterly report deliverable for the WVU Cooperative Agreement - Decontamination Systems Information and Research Program. Final reports for all of the 1997 projects will be submitted afterwards as one document. During this period, groundwater extraction operations were completed on Task 1.6 - Pilot Scale Demonstration of TCE Flushing Through PVDs at the DOE/RMI Extrusion Plant. The data have been evaluated and graphs are presented. The plot of TCE Concentration versus Time shows that the up-gradient groundwater monitoring well produced consistent levels of TCE contamination. A similar trend was observed for the down-gradient wells via grab samples tested. Groundwater samples from the PVD test pad Zone of Influence showed consistent reductions in TCE concentrations with respect to time. In addition, a natural pulse frequency is evident which will have a significant impact on the efficiency of the contaminant removal under natural groundwater advection/diffusion processes. The relationships between the PVD Extraction Flow Rate versus Cumulative Time shows a clear trend in flow rate. Consistent values between 20 to 30 g.p.m. at the beginning of the extraction duration, to less than 10 g.p.m. by the end of the extraction cycle are observed. As evidenced by the aquifer's diminishing recharge levels, the PVD extraction is affecting the response of the aquifer's natural attenuation capability. Progress was also marked on the Injection and Circulation of Potable Water Through PVDs task. Data reduction from this sequence of testing is ongoing. Work planned for next quarter includes completing the Injection / Extraction of potable water task and beginning the Surfactant Injection and removal task.

  20. Guides d’onde en verres et vitrocéramiques fluorés dopés terre rare élaborés par PVD pour l’émission dans le visible et la conversion de fréquence

    OpenAIRE

    Dieudonné , Belto

    2012-01-01

    The project joins in the development of miniaturized laser sources RGB for display and videoprojection, frequency conversion in solar cells.Fluoride glasses ZLAG ( ZrF4-LaF3-AlF3-GaF3) co-doped with rare earths were studied. This glass has a low phonon energy, a strong solubility of the rare earth ions and can be fabricated as thin films by PVD. It is also the precursor of transparent glass-ceramics. Similar emissions in both co-doped bulk and waveguides have been observed ; blue, orange, red...

  1. Low Conductive Thermal Barrier Coatings Produced by Ion Beam Assisted EB-PVD with Controlled Porosity, Microstructure Refinement and Alloying Additions for High Temperature Applications

    Science.gov (United States)

    Wolfe, Douglas E.; Singh, Jogender

    2005-01-01

    Various advanced Hafnia-based thermal barrier coatings (TBC) were applied on nickel-based superalloy coupons by electron beam physical vapor deposition. In addition, microstructural modifications to the coating material were made in an effort to reduce the thermal conductivity of the coating materials. Various processing parameters and coating system modifications were made in order to deposit the alloyed TBC with the desired microstructure and thus coating performance, some of which include applying coatings at substrate temperatures of 1150 C on both PtAl and CoNiCrAlY bond coated samples, as well as using 8YSZ as a bond layer. In addition, various characterization techniques including thermal cyclic tests, scanning electron microscopy, x-ray diffraction, thermal conductivity, and reflectivity measurements were performed. Although the coating microstructure was never fully optimized due to funding being cut short, significant reductions in thermal conductivity were accomplished through both chemistry changes (composition) and microstructural modifications.

  2. Tribological and mechanical properties of Ti/TiAlN/TiAlCN nanoscale multilayer PVD coatings deposited on AISI H11 hot work tool steel

    Energy Technology Data Exchange (ETDEWEB)

    AL-Bukhaiti, M.A., E-mail: m.albukhaiti@gmail.com [Mechanical Engineering Department, Faculty of Engineering, Sana’a University, Sana’a 12544 (Yemen); Al-hatab, K.A. [Mechanical Engineering Department, Faculty of Engineering, Sana’a University, Sana’a 12544 (Yemen); Tillmann, W.; Hoffmann, F.; Sprute, T. [Institute of Materials Engineering, Technische Universitat Dortmund, Leonhard-Euler-Str.2, 44227 Dortmund (Germany)

    2014-11-01

    Highlights: • New Ti/TiAlN/TiAlCN multilayer coating was developed. • It showed low wear rates (10{sup −16} m{sup 3}/N m), low friction coefficients (μ ∼ 0.25), and good hardness (17–20 GPa). • Friction coefficients and wear rates decrease and increase, respectively, with the increase in normal load and sliding velocity. • The coating/Al{sub 2}O{sub 3} pair showed superior wear resistance and low friction coefficient in comparison to coating/100Cr6 pair. - Abstract: A new [Ti/TiAlN/TiAlCN]{sub 5} multilayer coatings were deposited onto polished substrate AISI H11 (DIN 1.2343) steel by an industrial magnetron sputtering device. The tribological performance of the coated system was investigated by a ball-on-disk tribometer against 100Cr6 steel and Al{sub 2}O{sub 3} balls. The friction coefficients and specific wear rates were measured at various normal loads (2, 5, 8, and 10 N) and sliding velocities (0.2, 0.4, and 0.8 m/s) in ambient air and dry conditions. The phase structure, composition, wear tracks morphologies, hardness, and film/substrate adhesion of the coatings were characterized by light-microscopy, scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDX), X-ray diffraction (XRD), 3D-surface analyzer, nanoindentation, and scratch tests. Results showed that the deposited coatings showed low wear rates in the scale of 10{sup −15} m{sup 3}/N m, low friction coefficients against 100Cr6 and Al{sub 2}O{sub 3} balls in the range of 0.25–0.37, and good hardness in the range of 17–20 GPa. Results also revealed that the friction coefficients and disc wear rates decrease and increase, respectively with the increase in normal load and sliding velocity for both coating/Al{sub 2}O{sub 3} and coating/100Cr6 sliding system. Compared with the uncoated-H11 substrate, the deposited coating exhibited superior tribological and mechanical properties. The dominant wear mechanism was abrasive wear for coating/Al{sub 2}O{sub 3} pair, while

  3. Significance of a Noble Metal Nanolayer on the UV and Visible Light Photocatalytic Activity of Anatase TiO2 Thin Films Grown from a Scalable PECVD/PVD Approach.

    Science.gov (United States)

    Baba, Kamal; Bulou, Simon; Quesada-Gonzalez, Miguel; Bonot, Sébastien; Collard, Delphine; Boscher, Nicolas D; Choquet, Patrick

    2017-11-29

    UV and visible light photocatalytic composite Pt and Au-TiO 2 coatings have been deposited on silicon and glass substrates at low temperature using a hybrid ECWR-PECVD/MS-PVD process. Methylene blue, stearic acid, and sulfamethoxazole were used as dye, organic, and antibiotic model pollutants, respectively, to demonstrate the efficiency of these nanocomposite coatings for water decontamination or self-cleaning surfaces applications. Raman investigations revealed the formation of anatase polymorph of TiO 2 in all synthesized coatings with a shifting of the main vibrational mode peak to higher wavenumber in the case of Au-TiO 2 coating, indicating an increase number of crystalline defects within this coating. Because of the difference of the chemical potentials of each of the investigated noble metals, the sputtered metal layers exhibit different morphology. Pt sputtered atoms, with high surface adhesion, promote formation of a smooth 2D layer. On the other hand, Au sputtered atoms with higher cohesive forces promote the formation of 5-10 nm nanoparticles. As a result, the surface plasmon resonance phenomenon was observed in the Au-TiO 2 coatings. UV photoactivity of the nanocomposite coatings was enhanced 1.5-3 times and 1.3 times for methylene blue and stearic acid, respectively, thanks to the enhancement of electron trapping in the noble metal layer. This electron trapping phenomenon is higher in the Pt-TiO 2 coating because of its larger work function. On the other hand, the enhancement of the visible photoactivity was more pronounced (3 and 7 times for methylene blue and stearic acid, respectively) in the case of Au-TiO 2 thanks to the surface plasmon resonance. Finally, these nanocomposite TiO 2 coatings exhibited also a good ability for the degradation of antibiotics usually found in wastewater such as sulfamethoxazole. However, a complementary test have showed an increase of the toxicity of the liquid medium after photocatalysis, which could be due the

  4. Dependence of surface-enhanced infrared absorption (SEIRA) enhancement and spectral quality on the choice of underlying substrate: a closer look at silver (Ag) films prepared by physical vapor deposition (PVD).

    Science.gov (United States)

    Killian, Michelle M; Villa-Aleman, Eliel; Sun, Zhelin; Crittenden, Scott; Leverette, Chad L

    2011-03-01

    Silver (Ag) films of varying thickness were simultaneously deposited using physical vapor deposition (PVD) onto six infrared (IR) substrates (BaF(2), CaF(2), Ge, AMTIR, KRS-5, and ZnSe) in order to correlate the morphology of the deposited film with optimal SEIRA response and spectral band symmetry and quality. Significant differences were observed in the surface morphology of the deposited silver films, the degree of enhancement provided, and the spectral appearance of para-nitrobenzoic acid (PNBA) cast films for each silver-coated substrate. These differences were attributed to each substrate's chemical properties, which dictate the morphology of the Ag film and ultimately determine the spectral appearance of the adsorbed analyte and the magnitude of SEIRA enhancement. Routine SEIRA enhancement factors (EFs) for all substrates were between 5 and 150. For single-step Ag depositions, the following ranking identifies the greatest SEIRA enhancement factor and the maximum absorption of the 1345 cm(-1) spectral marker of PNBA at the optimal silver thickness for each substrate: BaF(2) (EF = 85 ± 19, 0.059 A, 10 nm Ag) > CaF(2) (EF = 75 ± 30, 0.052 A, 10 nm Ag) > Ge (EF = 45 ± 8, 0.019 A, 5 nm Ag) > AMTIR (EF = 38 ± 8, 0.024 A, 15 nm Ag) > KRS-5 (EF = 24 ± 1, 0.015 A, 12 nm Ag) > ZnSe (EF = 9 ± 5, 0.008 A, 8 nm Ag). A two-step deposition provides 59% larger EFs than single-step depositions of Ag on CaF(2). A maximum EF of 147 was calculated for a cast film of PNBA (surface coverage = 341 ng/cm(2)) on a 10 nm two-step Ag film on CaF(2) (0.102 A, 1345 cm(-1) symmetric NO(2) stretching band). The morphology of the two-step Ag film has smaller particles and greater particle density than the single-step Ag film.

  5. A.C. impedance, XRD, DSC, SEM and charge/discharge studies on Al2O3, TiO2, SiO2 dispersoid LiPF6/PVC/PVdF-co-HFP composite polymer electrolytes by phase inversion

    Science.gov (United States)

    Vickraman, P.; Gopukumar, S.

    2017-07-01

    The PVC/PVdF-co-HFP composite polymer electrolyte membranes (CPEMs) by varying blend ratios 1:1, 1:2, and 2:1 with fixed content of Al2O3, TiO2 and SiO2 having soaked in 0.5 M LiPF6 in EC/DEC (1:1) v/v) have been prepared by phase inversion. CPEMs of higher ionic conductivity (not dependent on electrolyte uptake as observed in our study) ASA4 (3.61×10-4 Scm-1), TSA3 (1.53×10-4 Scm-1), and SSA3 (4.81×10-4 Scm-1) have been only chosen for XRD, DSC, SEM and electrochemical studies. In XRD, crystalline peaks (phases) of PVdF have been noted with/without change in intensity as well as FWHM which correspond to type of filler interaction with host matrix. In DSC, it is observed that shifts in baseline, melting endotherms, and area under the endotherms indicating the thermal hist ory of PVC (Tg = 82 ° C) and melting of VdF crystallites varied with nature of the filler dispersoid. In SEM, the coagulated fibrils of the polymer coiled with the sponge like structure has been mapped. The charge/discharge studies are carried out on these CPEMs at C/10 rate in the voltage range 2.8 V - 4.2 V, and it is noted that the TSA3 showed better cycling performance with good capacity retention i.e., 50 cycles with 66% capacity retention than ASA4 of 28 cycles with 65% and SSA3 of 5 cycles with 56%. In the present study Coulombic efficiency is concerned only for first cycle and it is noted that the TSA3 showed 71% than 66% and 62% respectively for SSA3 and ASA4.

  6. The effect of microstructure at interface between coating and substrate on damping capacity of coating systems

    International Nuclear Information System (INIS)

    Wang, Xueqin; Pei, Yanling; Ma, Yue

    2013-01-01

    Samples with various interface microstructures between the coating and the substrate were designed and fabricated in this paper. Dynamic mechanical thermal analyzer (DMTA) was utilized to investigate the dynamic mechanical properties of the samples and scanning electron microscopy (SEM) was used to observe the interface microstructure between the substrate and coating. The effect of the interface microstructure on damping was studied, and results indicated that the larger the coating/substrate interface thickness was and the more interface defects were, the higher interface system damping was. When the micro-hardness ratio of substrate to coating was increased, the damping of coating system was enhanced. The effect of the APS and EB-PVD coating on damping capacity was investigated. There was a dramatic increase in the damping value of the APS coating when the strain was higher than 20 ppm, while the damping amplitude effect of the EB-PVD coating was not so obvious, which could mainly be caused by the different energy dissipation mechanisms of the two coatings.

  7. Damage evolution of TBC system under in-phase thermo-mechanical tests

    International Nuclear Information System (INIS)

    Kitazawa, R.; Tanaka, M.; Kagawa, Y.; Liu, Y.F.

    2010-01-01

    In-phase thermo-mechanical tests (TMF) of EB-PVD Y 2 O 3 -ZrO 2 thermal barrier coating (TBC) system (8 wt% Y 2 O 3 -ZrO 2 /CoNiCrAlY/IN-738 substrate) were done under a through-the-thick-direction thermal gradient from TBC surface temperature at 1150 deg. C to substrate temperature at 1000 deg. C. Deformation and failure behaviors of the TBC system were observed at the macroscopic and microscopic scales and damage evolution of the system under in-phase thermo-mechanical test was discussed. Special attention was paid to TBC layer cracking, thermally grown oxide (TGO) layer formation and void formation in bond coat and substrate. Effect of TMF conditions on the damage evolution behaviors was also discussed.

  8. Damage evolution of TBC system under in-phase thermo-mechanical tests

    Energy Technology Data Exchange (ETDEWEB)

    Kitazawa, R.; Tanaka, M.; Kagawa, Y. [Research Center for Advanced Science and Technology, University of Tokyo, 4-6-1 Komaba, Meguro-ku, Tokyo 153-8904 (Japan); Liu, Y.F., E-mail: yfliu@hyper.rcast.u-tokyo.ac.jp [Research Center for Advanced Science and Technology, University of Tokyo, 4-6-1 Komaba, Meguro-ku, Tokyo 153-8904 (Japan)

    2010-10-15

    In-phase thermo-mechanical tests (TMF) of EB-PVD Y{sub 2}O{sub 3}-ZrO{sub 2} thermal barrier coating (TBC) system (8 wt% Y{sub 2}O{sub 3}-ZrO{sub 2}/CoNiCrAlY/IN-738 substrate) were done under a through-the-thick-direction thermal gradient from TBC surface temperature at 1150 deg. C to substrate temperature at 1000 deg. C. Deformation and failure behaviors of the TBC system were observed at the macroscopic and microscopic scales and damage evolution of the system under in-phase thermo-mechanical test was discussed. Special attention was paid to TBC layer cracking, thermally grown oxide (TGO) layer formation and void formation in bond coat and substrate. Effect of TMF conditions on the damage evolution behaviors was also discussed.

  9. Gas Flow Detection System

    Science.gov (United States)

    Moss, Thomas; Ihlefeld, Curtis; Slack, Barry

    2010-01-01

    This system provides a portable means to detect gas flow through a thin-walled tube without breaking into the tubing system. The flow detection system was specifically designed to detect flow through two parallel branches of a manifold with only one inlet and outlet, and is a means for verifying a space shuttle program requirement that saves time and reduces the risk of flight hardware damage compared to the current means of requirement verification. The prototype Purge Vent and Drain Window Cavity Conditioning System (PVD WCCS) Flow Detection System consists of a heater and a temperature-sensing thermistor attached to a piece of Velcro to be attached to each branch of a WCCS manifold for the duration of the requirement verification test. The heaters and thermistors are connected to a shielded cable and then to an electronics enclosure, which contains the power supplies, relays, and circuit board to provide power, signal conditioning, and control. The electronics enclosure is then connected to a commercial data acquisition box to provide analog to digital conversion as well as digital control. This data acquisition box is then connected to a commercial laptop running a custom application created using National Instruments LabVIEW. The operation of the PVD WCCS Flow Detection System consists of first attaching a heater/thermistor assembly to each of the two branches of one manifold while there is no flow through the manifold. Next, the software application running on the laptop is used to turn on the heaters and to monitor the manifold branch temperatures. When the system has reached thermal equilibrium, the software application s graphical user interface (GUI) will indicate that the branch temperatures are stable. The operator can then physically open the flow control valve to initiate the test flow of gaseous nitrogen (GN2) through the manifold. Next, the software user interface will be monitored for stable temperature indications when the system is again at

  10. An X-ray photoelectron spectroscopic study of the B-N-Ti system

    Energy Technology Data Exchange (ETDEWEB)

    Seal, S. [Lawrence Berkeley National Lab., CA (United States); Barr, T.L. [Univ. of Wisconsin, Milwaukee, WI (United States); Sobczak, N. [Foundry Research Inst., Cracow (Poland); Benko, E. [Inst. of Metal Cutting, Cracow (Poland); Morgiel, J. [Polish Academy of Sciences, Cracow (Poland). Inst. of Metallurgy and Materials Science

    1997-03-01

    Composite nitrides (such as BN, TiN) are widely used in various industrial applications because of their extreme wear and corrosion resistance, thermal and electrical properties. In order to obtain composite materials with these optimal properties, it is important to elucidate whether any chemical reactions occur at nitride/metal interfaces, e.g., those involving BN-Ti/TiN. Materials of interest include the deposition by PVD of Ti and TiN on BN substrates. Some of these systems were then subjected to varying degrees of physical and thermal alteration. Detailed X-ray photoelectron spectroscopy (XPS) has therefore been rendered of these interfaces using cross-sectional display and sputter etching. Resulting structural and morphological features have been investigated with transmission electron microscopy (TEM) and X-ray diffraction (XRD). Diffusion of the nitridation, oxynitride formation and interfacial growth are of general interest.

  11. THE RESEARCH TECHNIQUES FOR ANALYSIS OF MECHANICAL AND TRIBOLOGICAL PROPERTIES OF COATING-SUBSTRATE SYSTEMS

    Directory of Open Access Journals (Sweden)

    Kinga CHRONOWSKA-PRZYWARA

    2014-06-01

    Full Text Available The article presents research techniques for the analysis of both mechanical and tribological properties of thin coatings applied on highly loaded machine elements. In the Institute of Machine Design and Exploitation, AGH University of Science and Technology students of the second level of Mechanical Engineering study tribology attending laboratory class. Students learn on techniques for mechanical and tribological testing of thin, hard coatings deposited by PVD and CVD technologies. The program of laboratories contains micro-, nanohardness and Young's modulus measurements by instrumental indentations and analysys of coating to substrate adhesion by scratch testing. The tribological properties of the coating-substrate systems are studied using various techniques, mainly in point contact load conditions with ball-on-disc and block-on-ring tribomiters as well as using ball cratering method in strongly abrasive suspensions.

  12. Development Status and Performance Comparisons of Environmental Barrier Coating Systems for SiCSiC Ceramic Matrix Composites

    Science.gov (United States)

    Zhu, Dongming; Harder, Bryan

    2016-01-01

    Environmental barrier coatings (EBC) and SiCSiC ceramic matrix composites (CMCs) will play a crucial role in future aircraft turbine engine systems, because of their ability to significantly increase engine operating temperatures, reduce engine weight and cooling requirements. This paper presents current NASA EBC-CMC development emphases including: the coating composition and processing improvements, laser high heat flux-thermal gradient thermo-mechanical fatigue - environmental testing methodology development, and property evaluations for next generation EBC-CMC systems. EBCs processed with various deposition techniques including Plasma Spray, Electron Beam - Physical Vapor Deposition, and Plasma Spray Physical Vapor Deposition (PS-PVD) will be particularly discussed. The testing results and demonstrations of advanced EBCs-CMCs in complex simulated engine thermal gradient cyclic fatigue, oxidizing-steam and CMAS environments will help provide insights into the coating development strategies to meet long-term engine component durability goals.

  13. Influence of material and testing parameters on the lifetime of TBC systems with MCrAlY and NiPtAl bondcoats

    Energy Technology Data Exchange (ETDEWEB)

    Song, Peng

    2012-08-31

    The oxidation behavior of the bond coat is an important factor determining the lifetime of thermal barrier coatings (TBC) in the advanced gas turbine components. In the present work, the effect of various testing parameters, such as hot/cold dwell time, heating/cooling rate, atmosphere composition on the bondcoat oxidation and associated TBC lifetime has been investigated. The range of coating systems included Electron Beam - Physical Vapor Deposited (EB-PVD) and Air Plasma Sprayed (APS) TBC's with MCrAlY (M = Ni, Co) and NiPtAl-bondcoats of various compositions. The effect of the testing parameters strongly depended on the type and properties of the studied system. The lifetime of EB-PVD TBC systems with conventional MCrAlY and NiPtAl bondcoats forming uniform, flat alumina scales was found to be limited by critical scale thickness, upon which a rapid crack propagation at the scale/bondcoat interface results in macroscopic failure. The lifetime of such systems was found to be affected by factors, which influence the scale growth rate and adherence (in particular by oxygen partial pressure (pO{sub 2}) and water vapor content in the test gas in the case of MCrAlY), whereas the temperature cyclic frequency showed no significant effect. NiPtAl bondcoats showed a superior behavior than the conventional MCrAlY-bondcoats due to slower scale growth rate and better scale adherence. For EB-PVD TBC systems with Zr-doped MCrAlYbondcoats the lifetime is mainly determined by the crack growth rate in the inhomogeneous inwardly growing oxide scales, whereas the lifetime is not dependent on the pO{sub 2} but rather on the cyclic frequency. For APS TBC systems the bondcoat oxidation is only one of several factors determining the ceramic topcoat lifetime. Therefore the oxide scale adherence is of less importance for lifetime of APS TBCs as compared to EBPVD TBCs. For the former systems, the cracks initiated at the convex asperities of the rough oxide scale / bondcoat interface

  14. Systems

    International Nuclear Information System (INIS)

    Anon.

    1980-01-01

    Papers in this session describe the concept of mined geologic disposal system and methods for ensuring that the system, when developed, will meet all technical requirements. Also presented in the session are analyses of system parameters, such as cost and nuclear criticality potential, as well as a technical analysis of a requirement that the system permit retrieval of the waste for some period of time. The final paper discusses studies under way to investigate technical alternatives or complements to the mined geologic disposal system. Titles of the presented papers are: (1) Waste Isolation System; (2) Waste Isolation Economics; (3) BWIP Technical Baseline; (4) Criticality Considerations in Geologic Disposal of High-Level Waste; (5) Retrieving Nuclear Wastes from Repository; (6) NWTS Programs for the Evaluation of Technical Alternatives or Complements to Mined Geologic Repositories - Purpose and Objectives

  15. systems

    Directory of Open Access Journals (Sweden)

    Alexander Leonessa

    2000-01-01

    Full Text Available A nonlinear robust control-system design framework predicated on a hierarchical switching controller architecture parameterized over a set of moving nominal system equilibria is developed. Specifically, using equilibria-dependent Lyapunov functions, a hierarchical nonlinear robust control strategy is developed that robustly stabilizes a given nonlinear system over a prescribed range of system uncertainty by robustly stabilizing a collection of nonlinear controlled uncertain subsystems. The robust switching nonlinear controller architecture is designed based on a generalized (lower semicontinuous Lyapunov function obtained by minimizing a potential function over a given switching set induced by the parameterized nominal system equilibria. The proposed framework robustly stabilizes a compact positively invariant set of a given nonlinear uncertain dynamical system with structured parametric uncertainty. Finally, the efficacy of the proposed approach is demonstrated on a jet engine propulsion control problem with uncertain pressure-flow map data.

  16. PVD and gas production: consider local resource access requirements

    International Nuclear Information System (INIS)

    Delafosse, E.

    1993-01-01

    The history of the natural gas industry worldwide teaches us that its development has sprung mainly from two sources: favorable contingent conditions, such as in the United States, where the discovery of large gas fields coincided favorably with technological progress and the already existing city gas distribution networks, as also happened in Italy and France; and political prodding, as in the Eastern European countries, in Japan, and certain countries of Western Europe too. Today, while natural gas is winning over more and more consumers and the infrastructures now exist, the rise in consumption is being held back by supply-related constraints, and namely the problem of adjusting to the rise in gas prices in the United States, and the distancing of the resources from Europe. In this context, the development of new gas markets in the developing countries could contribute to the continuous growth of the world natural gas industry. The resources do exist, and the possibility of generating electricity with them opens the way to creating or developing this industry in some twenty developing countries, to begin with, and a greater number later. For these countries, this perspective is highly enticing, economically; but development is slow, partly due to the fact that the specific requirements of gas production projects are not satisfied. The contractual and tax structure governing their implementation does not reflect the fact that, in contrast to the petroleum industry, the producer does not have access to a true market, and he is in fact only one of the wheels in an integrated production mechanism bent specifically on putting electrical power on the market. It is easy to see the difficulties that arise from such a situation, since the indispensable steps in the process, performed successively by producer, transporter, and electric company, use two interfaces with fields of business that are in close bilateral dependency. This leads to upstream inefficiency in investments and downstream inefficiency in trade. (author). 17 refs

  17. Evaluación de un puesto de PVD

    OpenAIRE

    Iturbe, Leire

    2012-01-01

    Actualmente, está fuera de duda que la ergonomía de los puestos con pantallas de visualización de datos constituye un requisito imprescindible para prevenir los problemas derivados del trabajo habitual y prolongado con este tipo de equipos: trastornos oculares, fatiga mental y problemas musculoesqueléticos. A estos problemas se encuentran expuestos actualmente extensos colectivos de trabajadores, colectivos cuyo crecimiento corre paralelo a la incesante expansión de la informática en las o...

  18. Software Design Document PVD CSCI (3). Volume 2, Appendices

    Science.gov (United States)

    1991-06-01

    FUNCTION: Igeneric -type(Type, Overline) called~y: show Ioverline in overlineif.c, (null) boundary-action in ovline-func.c, (null) Ideparture-action in...2.8.2.2-22 Ideparture-action 2.8.2.2-28 ldeparturejabel 2.8.2.2-27 idone__create_action 2.8.2.2-39 igeneric -size 2.8.2.2-17 lgeneric-type, 2.8.2.2-24

  19. Tribological Properties of PVD Ti/C-N Nanocoatnigs

    Science.gov (United States)

    Leitans, A.; Lungevics, J.; Rudzitis, J.; Filipovs, A.

    2017-04-01

    The present paper discusses and analyses tribological properties of various coatings that increase surface wear resistance. Four Ti/C-N nanocoatings with different coating deposition settings are analysed. Tribological and metrological tests on the samples are performed: 2D and 3D parameters of the surface roughness are measured with modern profilometer, and friction coefficient is measured with CSM Instruments equipment. Roughness parameters Ra, Sa, Sz, Str, Sds, Vmp, Vmc and friction coefficient at 6N load are determined during the experiment. The examined samples have many pores, which is the main reason for relatively large values of roughness parameter. A slight wear is identified in all four samples as well; its friction coefficient values range from 0,.21 to 0.29. Wear rate values are not calculated for the investigated coatings, as no expressed tribotracks are detected on the coating surface.

  20. Investigation of PVdF active diaphragms for synthetic jets

    Science.gov (United States)

    Bailo, Kelly C.; Brei, Diann E.; Calkins, Frederick T.

    2000-06-01

    Current research has shown that aircraft can gain significant aerodynamic performance benefits by employing active flow control (AFC). One of the enabling technologies of AFC is the synthetic jet. Synthetic jets, also known as zero-net-mass flux actuators, act as bi-directional pumps injecting high momentum air into the local aerodynamic flow. Previous work has concentrated on high frequency synthetic jets based on piezoelectric active diaphragms such as Thunder actuators. Low frequency synthetic jets present a unique challenge requiring large displacements, which current technology has difficulty meeting. Boeing is investigating novel shaped low frequency synthetic jets that can modify the flow over fixed aircraft wings. This paper present the initial study of two promising active diaphragm concepts: a crescent shape and an opposing bender shape. These active diaphragms were numerically modeled utilizing the general-purpose finite element code ABAQUS. Using the ABAQUS results, the dynamic volume change within each jet was calculated and incorporated into an analytical linear Bernoulli model to predict the velocities and pressures at the nozzle. Simulations were performed to determine trends to assist in selection of prototype configurations. Prototypes of both diaphragm concepts were constructed from polyvinylidene fluoride and experimentally tested at Boeing with promising results.

  1. Nanocoatings for High-Efficiency Industrial and Tooling Systems

    Energy Technology Data Exchange (ETDEWEB)

    Blau, P; Qu, J.; Higdon, C. (Eaton Corporation)

    2011-02-01

    This industry-driven project was the result of a successful response by Eaton Corporation to a DOE/ITP Program industry call. It consisted of three phases in which ORNL participated. In addition to Eaton Corporation and ORNL (CRADA), the project team included Ames Laboratory, who developed the underlying concept for aluminum-magnesium-boron based nanocomposite coatings [1], and Greenleaf, a small tooling manufacturer in western Pennsylvania. This report focuses on the portion of this work that was conducted by ORNL in a CRADA with Eaton Corporation. A comprehensive final report for the entire effort, which ended in September 2010, has been prepared by Eaton Corporation. Phase I, “Proof of Concept” ran for one year (September 1, 2006 to September 30, 2007) during which the applicability of AlMgB14 single-phase and nanocomposite coatings on hydraulic material coupons and components as well as on tool inserts was demonstrated.. The coating processes used either plasma laser deposition (PLD) or physical vapor deposition (PVD). During Phase I, ORNL conducted laboratory-scale pin-on-disk and reciprocating pin-on-flat tests of coatings produced by PLD and PVD. Non-coated M2 tool steel was used as a baseline for comparison, and the material for the sliding counterface was Type 52100 bearing steel since it simulated the pump materials. Initial tests were run mainly in a commercial hydraulic fluid named Mobil DTE-24, but some tests were later run in a water-glycol mixture as well. A tribosystem analysis was conducted to define the operating conditions of pump components and to help develop simulative tests in Phase II. Phase II, “Coating Process Scale-up” was intended to use scaled-up process to generate prototype parts. This involved both PLD practices at Ames Lab, and a PVD scale-up study at Eaton using its production capable equipment. There was also a limited scale-up study at Greenleaf for the tooling application. ORNL continued to conduct friction and wear

  2. SYSTEM

    Directory of Open Access Journals (Sweden)

    K. Swarnalatha

    2013-01-01

    Full Text Available Risk analysis of urban aquatic systems due to heavy metals turns significant due to their peculiar properties viz. persis tence, non-degradab ility, toxicity, and accumulation. Akkulam Veli (AV, an urba n tropical lake in south India is subjected to various environmental stresses due to multiple waste discharge, sand mining, developmental activities, tour ism related activitie s etc. Hence, a comprehensive approach is adopted for risk assessment using modified degree of contamination factor, toxicity units based on numerical sediment quality guidelines (SQGs, and potentialecological risk indices. The study revealed the presence of toxic metals such as Cr, C d, Pb and As and the lake is rated under ‘low ecological risk’ category.

  3. A wideband optical monitor for a planetary-rotation coating-system

    International Nuclear Information System (INIS)

    Campanelli, M.B.; Smith, D.J.

    1998-01-01

    A substrate-specific, through-planet, wideband optical coating monitor is being developed to increase production yield and the understanding of physical vapor deposition (PVD) coatings fabricated in the Optical Manufacturing Laboratory at the University of Rochester's Laboratory for Laser Energetics. In-situ wideband optical monitoring of planetary rotation systems allows direct monitoring of large, expensive substrates with complex layering schemes. The optical monitor discussed here is under development for coating several large (e.g., 80.7 x 41.7 x 9.0 cm) polarizers for the National Ignition Facility. Wideband optical monitoring of the production substrates is used in concert with an array of crystal monitors for process control, film parameter evaluation, and error detection with associated design reoptimization. The geometry of a planetary rotation system, which produces good uniformity across large substrates, makes optical monitoring more difficult. Triggering and timing techniques for data acquisition become key to the process because the optical coating is available only intermittently for monitoring. Failure to properly consider the effects of the system dynamics during data retrieval and processing may result in significant decreases in the spectral data's reliability. Improved data accuracy allows better determination of film thicknesses, indices, and inhomogeneities and enables in-situ error detection for design reoptimization

  4. Data of evolutionary structure change: 1PVDA-2NXWB [Confc[Archive

    Lifescience Database Archive (English)

    Full Text Available 1PVDA-2NXWB 1PVD 2NXW A B SEITLGKYLFERLKQVNVNTVFGLPGDFNLSLLDKIYEV...STLGVAAVTYGAGAFNMVNAVAGAYAEKSPVVVISGAPGTTEL------LDTQFQVFKEITVAQARLDDPAKAPAEIARVLGAARAQSRPVYLEIPRNMVNAEVEP--VGDDPA---WPVD...0 1PVD A 1PVDA ...CA 231 1PVD A 1PVD...> 1 1PVD A 1PVD

  5. On the compatibility of single crystal superalloys with a thermal barrier coating system

    Energy Technology Data Exchange (ETDEWEB)

    Wu, R.T. [Department of Materials, Imperial College London, Prince Consort Road, London SW7 2BP (United Kingdom); Reed, R.C. [Department of Materials, Imperial College London, Prince Consort Road, London SW7 2BP (United Kingdom)], E-mail: r.reed@birmingham.ac.uk

    2008-02-15

    The compatibility of three Co-containing prototype single crystal nickel-based superalloys with a thermal barrier coating (TBC) system is examined. These contain 2.1, 8.4 and 12.6 at.% Co; the concentrations of Al, Cr, Ta, W, Re, Hf are identical and chosen to be representative of advanced grades of these alloys. The TBC consists of an yttria-stabilized zirconia (YSZ) layer formed by electron beam physical vapour deposition (EB-PVD) and a bond coat made by electrodeposited platinum with a subsequent interdiffusion heat treatment - a so-called 'platinum-diffused' bond coat. The resistance to spallation of the TBC system is degraded as the Co content of the substrate increases. Wavelength-dispersive X-ray analysis and secondary ion mass spectrometry indicate that quantities of Co are present in the thermally grown oxide (TGO) by the time that failure occurs, this effect being most pronounced when the Co content of the substrate is high; the TGO is then more wavy and convoluted. The bond coat consists exclusively of the {gamma} and {gamma}' phases, with the balance shifting towards {gamma} with increasing thermal exposure; the loss of Al from the bond coat due to TGO formation means that the TGO is eventually in contact with the {gamma} phase solely, which is enriched in Co.

  6. Disease-Related Microstructural Differences in the Brain in Women With Provoked Vestibulodynia.

    Science.gov (United States)

    Gupta, Arpana; Woodworth, Davis C; Ellingson, Benjamin M; Rapkin, Andrea J; Naliboff, Bruce; Kilpatrick, Lisa A; Stains, Jean; Masghati, Salome; Tillisch, Kirsten; Mayer, Emeran A; Labus, Jennifer S

    2018-05-01

    Provoked vestibulodynia (PVD) is a chronic pelvic pain disorder affecting 16% of the female population. Neuroimaging studies have highlighted central abnormalities in PVD, similar to other chronic pelvic pain disorders, including brain regions involved in sensory processing and modulation of pain. The aim of the study was to determine alterations in the subvoxel, microstructural organization within tissues in PVD compared with healthy control participants (HCs) and a disease control group (irritable bowel syndrome [IBS]). Diffusion tensor imaging magnetic resonance imaging was conducted in 87 age-matched premenopausal women (29 PVD, 29 HCs, 29 IBS). Statistical parameter mapping of fractional anisotropy (FA) and mean diffusivity (MD) maps were used to identify microstructural difference in the brain specific to PVD or shared with IBS. PVD alterations in microstructural organization of the brain were predominantly observed in fibers associated with sensorimotor integration and pain processing that relay information between the thalamus, basal ganglia, sensorimotor, and insular cortex. PVD, compared with HCs, showed extensive increases in the FA of somatosensory and basal ganglia regions. In contrast, PVD and IBS subjects did not show any FA-related group differences. PVD subjects showed greater MD in the basal ganglia compared with HCs (higher MD in the internal capsule and pallidum) and IBS (higher MD in the putamen and pallidum). Increases in MD were associated with increased vaginal muscle tenderness and vulvar pain. The current findings highlight possible shared mechanisms between 2 different pelvic pain disorders, but also highlight the widespread alterations observed specifically in PVD compared with HCs. Alterations in microstructure in PVD were observed in fibers associated with sensorimotor integration and pain processing, which were also associated with increased vaginal muscle tenderness and vulvar pain. These alterations may be contributing to increased

  7. Achievement report for fiscal 1998 on area consortium research and development business, 1st year. Area consortium energy research and development (molding material processing eco-system using powder lubricant); 1998 nendo chiiki consortium energy kenkyu kaihatsu bun'ya. Funtai rikei junkatsuzai wo mochiita sokeizai kako eko system no kenkyu kaihatsu (dai 1 nendo)

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1999-03-01

    A material processing technology demanding but low energy and cost and causing low environmental impact was developed using a powder lubricant in a closed metal die system. An inorganic powder excellent in adhesiveness as lubricant was discovered. Powder lubricants for die casting and new carbon lubricants for metal die forging were also developed. In a test in an eco-die casting system, it was found that power was better than water solution in terms of finish and energy efficiency. In the development of a metal forging system using a powder lubricant, existing graphite lubricants and new powder lubricants containing fullerene were subjected to evaluation (ring tests). Two types of graphite solutions now in use and two powder lubricants were evaluated by the ring tests, and this enabled the comprehension of powder lubricant characteristics. For the development of a die casting system requiring no lubricant, a metal die surface treatment method was found that produces a surface excellent in resisting erosion by the application of the aluminizing ion nitriding composite treatment method. In addition, wettability was compared between a PVD (physical vapor deposition)-formed nitride film and the powder lubricant constituents. The report also refers to surveys conducted for commercialization. (NEDO)

  8. Environmental Stability and Oxidation Behavior of HfO2-Si and YbGd(O) Based Environmental Barrier Coating Systems for SiCSiC Ceramic Matrix Composites

    Science.gov (United States)

    Zhu, Dongming; Farmer, Serene; McCue, Terry R.; Harder, Bryan; Hurst, Janet B.

    2017-01-01

    Ceramic environmental barrier coatings (EBC) and SiCSiC ceramic matrix composites (CMCs) will play a crucial role in future aircraft propulsion systems because of their ability to significantly increase engine operating temperatures, improve component durability, reduce engine weight and cooling requirements. Advanced EBC systems for SiCSiC CMC turbine and combustor hot section components are currently being developed to meet future turbine engine emission and performance goals. One of the significant material development challenges for the high temperature CMC components is to develop prime-reliant, environmental durable environmental barrier coating systems. In this paper, the durability and performance of advanced Electron Beam-Physical Vapor Deposition (EB-PVD) NASA HfO2-Si and YbGdSi(O) EBC bond coat top coat systems for SiCSiC CMC have been summarized. The high temperature thermomechanical creep, fatigue and oxidation resistance have been investigated in the laboratory simulated high-heat-flux environmental test conditions. The advanced NASA EBC systems showed promise to achieve 1500C temperature capability, helping enable next generation turbine engines with significantly improved engine component temperature capability and durability.

  9. Parameters affecting TGO growth rate and the lifetime of TBC systems with MCrAlY-bondcoats

    Energy Technology Data Exchange (ETDEWEB)

    Toscano, J.; Naumenko, D.; Singheiser, L.; Quadakkers, W.J. [Forschungszentrum Juelich GmbH, IEF 2, Juelich (Germany); Gil, A. [AGH University of Science and Technology, Faculty of Materials Science and Ceramics, Krakow (Poland)

    2008-06-15

    In the present work different parameters which affect the oxide growth on MCrAlY-bondcoats have been studied, in an attempt to find a reliable way to define the critical oxide thickness to failure of an EB-PVD thermal barrier coatings (TBC). It was found that the variation of selected parameters such as oxidation temperature, surface roughness, and bondcoat thickness certainly alters the thermally grown oxide (TGO) growth rate. However, simultaneously the morphology, composition, and/or microstructure of the oxide are changed, which can affect the critical TGO thickness to failure in a TBC system. In contrast, the variation of the oxygen partial pressure of the oxidizing atmosphere led to different TGO growth rates without significantly changing the oxide morphology and composition. Comparing the TGOs grown at different rates in the specimens exposed to high pO{sub 2} and low pO{sub 2} atmospheres, it was estimated that at failure the oxide scales in both specimens have reached a similar critical thickness. (Abstract Copyright [2008], Wiley Periodicals, Inc.)

  10. Data of evolutionary structure change: 1PVDB-2VBIG [Confc[Archive

    Lifescience Database Archive (English)

    Full Text Available 1PVDB-2VBIG 1PVD 2VBI B G SEITLGKYLFERLKQVNVNTVFGLPGDFNLSLLDKIYEVEGMRWAGNANELNAAYAADGYARIKGMSCIITTFGVGELSALNGIAGSYAEHVG...HHHHHHHHHH 0 1PVD B 1PVDB SFNDN-SKIRM 1PVD B 1PVDB 1PVD B 1PVD

  11. Antioxidant Enzymes Activity in Patients with Peripheral Vascular Disease, with and without Presence of Diabetes Mellitus

    OpenAIRE

    Jandrić-Balen, Marica; Božikov, Veljko; Bistrović, Dragica; Jandrić, Ivan; Božikov, Jadranka; Romić, Željo; Balen, Ivan

    2003-01-01

    The study evaluated antioxidant status in patients with peripheral vascular disease (PVD), with and without concomitant diabetes mellitus (DM). 211 participants were divided into standardized 4 groups: patients with PVD and DM (PVD+DM+), patients with PVD without DM (PVD+DM-), patients without PVD with DM (PVD-DM+) and patients without PVD and DM (PVD-DM-). The diagnosis of PVD was established by Doppler sonography analysis, including determination of the ankle brachial index (...

  12. Structural, dielectric and ferroelectric properties of (Bi,Na)TiO{sub 3}–BaTiO{sub 3} system studied by high throughput screening

    Energy Technology Data Exchange (ETDEWEB)

    Hayden, Brian E. [Ilika Technologies Plc., Kenneth Dibben House, Enterprise Road, University of Southampton Science Park, Chilworth, Southampton SO16 7NS (United Kingdom); Department of Chemistry, University of Southampton, Highfield, Southampton SO17 1BJ (United Kingdom); Yakovlev, Sergey, E-mail: sergey.yakovlev@ilika.com [Ilika Technologies Plc., Kenneth Dibben House, Enterprise Road, University of Southampton Science Park, Chilworth, Southampton SO16 7NS (United Kingdom)

    2016-03-31

    Thin-film materials libraries of the Bi{sub 2}O{sub 3}–Na{sub 2}O–TiO{sub 2}–BaO system in a broad composition range have been deposited in ultra-high vacuum from elemental evaporation sources and an oxygen plasma source. A high throughput approach was used for systematic compositional and structural characterization and the screening of the dielectric and ferroelectric properties. The perovskite (Bi,Na)TiO{sub 3}–BaTiO{sub 3} phase with a Ba concentration near the morphotropic phase boundary (ca. 6 at.%) exhibited a relative dielectric permittivity of 180, a loss tangent of 0.04 and remnant polarization of 19 μC/cm{sup 2}. Compared to published data, observed remnant polarization is close to that known for epitaxially grown films but higher than the values reported for polycrystalline films. The high throughput methodology and systematic nature of the study allowed us to establish the composition boundaries of the phase with optimal dielectric and ferroelectric characteristics. - Highlights: • Bi{sub 2}O{sub 3}–Na{sub 2}O–TiO{sub 2}–BaO high throughput materials library was deposited using PVD method. • Materials were processed from individual molecular beam epitaxy sources of elements. • High throughput approach was used for structural, dielectric and ferroelectric study. • Composition boundaries of perovskite compounds with optimum properties are reported.

  13. Structural, dielectric and ferroelectric properties of (Bi,Na)TiO3–BaTiO3 system studied by high throughput screening

    International Nuclear Information System (INIS)

    Hayden, Brian E.; Yakovlev, Sergey

    2016-01-01

    Thin-film materials libraries of the Bi 2 O 3 –Na 2 O–TiO 2 –BaO system in a broad composition range have been deposited in ultra-high vacuum from elemental evaporation sources and an oxygen plasma source. A high throughput approach was used for systematic compositional and structural characterization and the screening of the dielectric and ferroelectric properties. The perovskite (Bi,Na)TiO 3 –BaTiO 3 phase with a Ba concentration near the morphotropic phase boundary (ca. 6 at.%) exhibited a relative dielectric permittivity of 180, a loss tangent of 0.04 and remnant polarization of 19 μC/cm 2 . Compared to published data, observed remnant polarization is close to that known for epitaxially grown films but higher than the values reported for polycrystalline films. The high throughput methodology and systematic nature of the study allowed us to establish the composition boundaries of the phase with optimal dielectric and ferroelectric characteristics. - Highlights: • Bi 2 O 3 –Na 2 O–TiO 2 –BaO high throughput materials library was deposited using PVD method. • Materials were processed from individual molecular beam epitaxy sources of elements. • High throughput approach was used for structural, dielectric and ferroelectric study. • Composition boundaries of perovskite compounds with optimum properties are reported.

  14. Safety and Effectiveness of Bone Marrow Cell Concentrate in the Treatment of Chronic Critical Limb Ischemia Utilizing a Rapid Point-of-Care System

    Directory of Open Access Journals (Sweden)

    Venkatesh Ponemone

    2017-01-01

    Full Text Available Critical limb ischemia (CLI is the end stage of lower extremity peripheral vascular disease (PVD in which severe obstruction of blood flow results in ischemic rest pain, ulcers and/or gangrene, and a significant risk of limb loss. This open-label, single-arm feasibility study evaluated the safety and therapeutic effectiveness of autologous bone marrow cell (aBMC concentrate in revascularization of CLI patients utilizing a rapid point-of-care device. Seventeen (17 no-option CLI patients with ischemic rest pain were enrolled in the study. Single dose of aBMC, prepared utilizing an intraoperative point-of-care device, the Res-Q™ 60 BMC system, was injected intramuscularly into the afflicted limb and patients were followed up at regular intervals for 12 months. A statistically significant improvement in Ankle Brachial Index (ABI, Transcutaneous Oxygen Pressure (TcPO2, mean rest pain and intermittent claudication pain scores, wound/ ulcer healing, and 6-minute walking distance was observed following aBMC treatment. Major amputation-free survival (mAFS rate and amputation-free rates (AFR at 12 months were 70.6% and 82.3%, respectively. In conclusion, aBMC injections were well tolerated with improved tissue perfusion, confirming the safety, feasibility, and preliminary effectiveness of aBMC treatment in CLI patients.

  15. Preparation and characterization of poly(vinylidene fluoride) based composite electrolytes for electrochemical devices

    International Nuclear Information System (INIS)

    Karabelli, D.; Leprêtre, J.-C.; Cointeaux, L.; Sanchez, J.-Y.

    2013-01-01

    Highlights: • Macroporous PVdF based membranes for electrochemical applications were prepared with support materials. • Woven PET and PA fabrics and non-woven cellulose paper are used as support materials. • Porous structure of PVdF was obtained on the support material. • Interaction between the electrolyte solvent and the composite material played an important role on the mechanical properties. • Compared to the pure PVdF separators, enhanced mechanical strength was obtained for composite separators, without decreasing the ionic conductivity. -- Abstract: PVdF-based separators are very promising materials in electrochemical energy storage systems but they suffer from fairly poor mechanical properties. To overcome this drawback, composite PVdF separators were fabricated and characterized in electrolytes of Li-ion batteries and supercapacitors. Macroporous PVdF composite separators were prepared by phase inversion method using PA and PET, and non-woven cellulose as support layers. Ionic conductivity and thermomechanical analyses were performed using electrolytes of Li-ion batteries and supercapacitors. The composite approach allowed a tremendous increase of the mechanical performances of the separator (between 340 and 750 MPa) compared to the unreinforced PVdF separator (56 MPa), without compromising the ionic conductivities (up to 15.6 mS cm −1 )

  16. Tribological study of hard coatings without cobalt intended to isolation components of PWR primary cooling system; Etude tribologique de revetements durs sans cobalt destines aux organes d`isolement du circuit primaire des REP

    Energy Technology Data Exchange (ETDEWEB)

    Cachon, L.

    1995-10-18

    The objective is to qualify coatings without cobalt to replace ``Stellites`` coatings in isolation valves of PWR primary cooling system, as Co is activated when passing in the reactor core and contaminated the cooling loop. Three families of coatings were tested: PVD thin films from 1 to 8 {mu}m monolayers of Cr/C{sub x} with x varying between 1.6 and 9.5 at% or multilayers of pure chromium and Cr/C{sub 1.6} at%, coatings with a thickness between 100 and 200 {mu}m of cermets NiCr{sub y} (y varying from 5 to 35 at%) matrix binding chromium or tungsten carbides, and thick coatings 2 mm thickness of cermets Nitronic 60 or Inconel 625 matrix binding 10, 20 or 30% titanium or niobium carbides. Stellite 6 (2 mm) is the reference coating for tribology. Coatings were qualified and selected by thermal shocks, corrosion and plane friction. The thin film and the thick families were disqualified by their destruction or by their high friction coefficient. Then coatings between 100 and 200 {mu}m were used in a valve mock-up working in PWR primary cooling system pressure and temperature conditions. Tests show that these coatings have better wear or tightness performances than stellite 6, except for a slightly higher friction coefficient. (A.B.).

  17. HTS 63_4_ VANZYL FJ v Z _PvdM

    African Journals Online (AJOL)

    p1243322

    such suffering indicates the enormous guilt and existence of every sinner. .... made God self known as the God who forgives us our sins, a decision was taken on two .... condition of sin emanating from it affects the whole human being, without.

  18. Development of tantalum oxynitride thin films produced by PVD: Study of structural stability

    Energy Technology Data Exchange (ETDEWEB)

    Cristea, D. [Centro de Física, Universidade do Minho, Campus de Gualtar, 4710-057 Braga (Portugal); Department of Materials Science, Transylvania University, 500036 Brasov (Romania); Crisan, A. [Department of Materials Science, Transylvania University, 500036 Brasov (Romania); Barradas, N.P.; Alves, E. [Instituto Superior Técnico, Universidade Técnica de Lisboa Estrada Nacional 10, ao km 139,7 2695-066, Bobadela LRS (Portugal); Moura, C.; Vaz, F. [Centro de Física, Universidade do Minho, Campus de Gualtar, 4710-057 Braga (Portugal); Cunha, L., E-mail: lcunha@fisica.uminho.pt [Centro de Física, Universidade do Minho, Campus de Gualtar, 4710-057 Braga (Portugal)

    2013-11-15

    The purpose of this work is to study the evolution of the structure and of the thermal stability of a group of tantalum oxynitride thin films, prepared by magnetron sputtering, under the influence of vacuum annealing, up to a temperature of 800 °C. When varying the partial pressure of the reactive gases (P{sub O{sub 2+N{sub 2}}}), during the deposition process, the films change from a structure with a combination of poorly developed crystallites of the tetragonal β-Ta and of the face centred cubic (fcc) Ta(O,N) phases, for the films deposited with low P{sub O2+N2}, to a quasi-amorphous structure, for the films deposited with highest pressures. For intermediate pressures, the films reveal the presence of the fcc-Ta(O,N) structure. This structure corresponds to O atoms substituting some of the N atoms on the fcc-TaN structure and/or N atoms substituting O atoms of the fcc-γ-TaO structure. When subjected to the thermal annealing at 700 °C or higher, the film produced with lowest partial pressure revealed a remarkable structural change. New diffraction peaks appear and can only be attributed to a sub-stoichiometric hexagonal tantalum nitride structure. The film did not reveal any signs of delamination or cracks after all annealing temperatures. The two films produced with highest partial pressure proved to be the most stable. Structurally, they maintain the amorphous structure after all the annealing treatments and, in addition, no cracks or delamination were detected.

  19. Monitoring of PVD, PECVD and etching plasmas using Fourier components of RF voltage

    International Nuclear Information System (INIS)

    Dvorak, P; Vasina, P; Bursikova, V; Zemlicka, R

    2010-01-01

    Fourier components of discharge voltages were measured in two different reactive plasmas and their response to the creation or destruction of a thin film was studied. In reactive magnetron sputtering the effect of transition from the metallic to the compound mode accompanied by the creation of a compound film on the sputtered target was observed. Further, deposition and etching of a diamond-like carbon film and their effects on amplitudes of Fourier components of the discharge voltage were studied. It was shown that the Fourier components, including higher harmonic frequencies, sensitively react to the presence of a film. Therefore, they can be used as a powerful tool for the monitoring of deposition and etching processes. It was demonstrated that the behaviour of the Fourier components was caused in both experiments by the presence of the film. It was not caused by changes in the chemical composition of the gas phase induced by material etched from the film or decrease in gettering rate. Further, the observed behaviour was not affected by the film conductivity. The behaviour of the Fourier components can be explained by the difference between the coefficients of secondary electron emission of the film and its underlying material.

  20. Microstructure and properties of TiAlSiN coatings prepared by hybrid PVD technology

    International Nuclear Information System (INIS)

    Yu Donghai; Wang Chengyong; Cheng Xiaoling; Zhang Fenglin

    2009-01-01

    TiAlSiN coatings with different Si content were prepared by hollow cathode discharge (HCD) and mid-frequency magnetron sputtering (MFMS) hybrid coating deposition technology. The chemical composition, microstructure, mechanical properties of these coatings were systematically investigated by means of energy dispersive spectrometry (EDS), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), nanoindentation measurement, scratch and high speed milling hardened steel tests. The coatings prepared by this method showed the structure of crystalline phase was corresponding to that of TiAlN, however, different preferred orientation with addition of Si. Proper content of Si into TiAlN led to increase of microhardness and adhesion. TiAlSiN coated end mill with Si content of 4.78 at.% had the least flank wear, which was improved about 20% milling distance than TiAlN coated end mill.

  1. Microstructure and properties of TiAlSiN coatings prepared by hybrid PVD technology

    Energy Technology Data Exchange (ETDEWEB)

    Yu Donghai [Faculty of Electromechanical Engineering, Guangdong University of Technology, Guangzhou 510006 (China); Wang Chengyong, E-mail: cywang@gdut.edu.c [Faculty of Electromechanical Engineering, Guangdong University of Technology, Guangzhou 510006 (China); Cheng Xiaoling; Zhang Fenglin [Faculty of Electromechanical Engineering, Guangdong University of Technology, Guangzhou 510006 (China)

    2009-07-01

    TiAlSiN coatings with different Si content were prepared by hollow cathode discharge (HCD) and mid-frequency magnetron sputtering (MFMS) hybrid coating deposition technology. The chemical composition, microstructure, mechanical properties of these coatings were systematically investigated by means of energy dispersive spectrometry (EDS), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), nanoindentation measurement, scratch and high speed milling hardened steel tests. The coatings prepared by this method showed the structure of crystalline phase was corresponding to that of TiAlN, however, different preferred orientation with addition of Si. Proper content of Si into TiAlN led to increase of microhardness and adhesion. TiAlSiN coated end mill with Si content of 4.78 at.% had the least flank wear, which was improved about 20% milling distance than TiAlN coated end mill.

  2. High-quality PVD graphene growth by fullerene decomposition on Cu foils

    Czech Academy of Sciences Publication Activity Database

    Azpeitia, J.; Otero-Irurueta, G.; Palacio, I.; Martinez, J. I.; Ruiz del Arbol, N.; Santoro, G.; Gutiérrez, A.; Aballe, L.; Foerster, M.; Kalbáč, Martin; Valeš, Václav; Mompean, F. J.; Garcia-Hernandez, M.; Martín-Gago, J.A.; Munuera, C.; Lopez, M. F.

    2017-01-01

    Roč. 119, AUG 2017 (2017), s. 535-543 ISSN 0008-6223 R&D Projects: GA MŠk LL1301 EU Projects: European Commission(XE) 696656 - GrapheneCore1 Institutional support: RVO:61388955 Keywords : functional perturbation- theory * epitaxial graphene * copper substrate * pt(111) surface * raman-spectrum * cvd-graphene Subject RIV: CF - Physical ; Theoretical Chemistry OBOR OECD: Physical chemistry Impact factor: 6.337, year: 2016

  3. Mathematical analysis of the Photovoltage Decay (PVD) method for minority carrier lifetime measurements

    Science.gov (United States)

    Vonroos, O. H.

    1982-01-01

    When the diffusion length of minority carriers becomes comparable with or larger than the thickness of a p-n junction solar cell, the characteristic decay of the photon-generated voltage results from a mixture of contributions with different time constants. The minority carrier recombination lifetime tau and the time constant l(2)/D, where l is essentially the thickness of the cell and D the minority carrier diffusion length, determine the signal as a function of time. It is shown that for ordinary solar cells (n(+)-p junctions), particularly when the diffusion length L of the minority carriers is larger than the cell thickness l, the excess carrier density decays according to exp (-t/tau-pi(2)Dt/4l(2)), tau being the lifetime. Therefore, tau can be readily determined by the photovoltage decay method once D and L are known.

  4. Magnesium substituted hydroxyapatite formation on (Ti,Mg)N coatings produced by cathodic arc PVD technique

    International Nuclear Information System (INIS)

    Onder, Sakip; Kok, Fatma Nese; Kazmanli, Kursat; Urgen, Mustafa

    2013-01-01

    In this study, formation of magnesium substituted hydroxyapatite (Ca 10−x Mg x (PO 4 ) 6 (OH) 2 ) on (Ti,Mg)N and TiN coating surfaces were investigated. The (Ti 1−x ,Mg x )N (x = 0.064) coatings were deposited on titanium substrates by using cathodic arc physical vapor deposition technique. TiN coated grade 2 titanium substrates were used as reference to understand the role of magnesium on hydroxyapatite (HA) formation. The HA formation experiments was carried out in simulated body fluids (SBF) with three different concentrations (1X SBF, 5X SBF and 5X SBF without magnesium ions) at 37 °C. The coatings and hydroxyapatite films formed were characterized by scanning electron microscope (SEM), X-ray diffraction (XRD) and FTIR Spectroscopy techniques. The energy dispersive X-ray spectroscopy (EDS) analyses and XRD investigations of the coatings indicated that magnesium was incorporated in the TiN structure rather than forming a separate phase. The comparison between the TiN and (Ti, Mg)N coatings showed that the presence of magnesium in TiN structure facilitated magnesium substituted HA formation on the surface. The (Ti,Mg)N coatings can potentially be used to accelerate the HA formation in vivo conditions without any prior hydroxyapatite coating procedure. - Highlights: • Mg incorporated in (Ti,Mg)N coating structure and did not form a separate phase • Mg dissolution in SBF solution facilitated Mg-substituted hydroxyapatite formation • (Ti,Mg)N acted as Mg-source for Mg-substituted hydroxyapatite formation in SBF

  5. The morphology and structure of PVD ZrN-Cu thin films

    International Nuclear Information System (INIS)

    Audronis, M; Jimenez, O; Leyland, A; Matthews, A

    2009-01-01

    ZrN-Cu thin films containing variable amounts of copper, namely 8, 33 and 58 at%, were produced by reactive pulsed unbalanced magnetron sputtering. Coatings were found to possess hardness values of 22.5 GPa, 9.5 GPa and 3.7 GPa, respectively. The morphology of coatings was investigated by field emission gun scanning electron microscopy and the structure (microstructure and nanostructure) was investigated by conventional (bright-field and dark-field imaging) and high-resolution transmission electron microscopy. Complementary x-ray diffraction experiments were also performed. ZrN coatings containing 8 at% of copper were found to possess a nano-columnar structure composed of ZrN columnar grains, the diameter of which was approximately 15-35 nm. The majority of the copper content was apparently dissolved within the ZrN grains, rather than existing as a separate phase. Coatings of the two other compositions were found to be composed of a mixture of mostly equiaxed ZrN and Cu nano-crystalline grains, the diameters of which were in the approximate range 5-25 nm. None of the coatings investigated in this study were found to possess the so-called 'nanocomposite' structure, which is often envisaged as crystalline nano-grains surrounded by a thin amorphous intergranular phase. Instead, coatings were found to be either single-phase ZrN (with Cu in substitutional solid solution for Zr) or a mixture of ZrN and Cu nano-grains.

  6. Corrosion protection of PVD and paint coatings for selective solar absorber surfaces

    OpenAIRE

    Nunes, A.; Carvalho, M. J.; Diamantino, Teresa C.; Fernandes, J. C. S.

    2015-01-01

    The selective solar absorber surface is a fundamental part of a solar thermal collector, as it is responsible for the solar radiation absorption and for reduction of radiation heat losses. The surface’s optical properties, the solar absorption (á) and the emittance (å), have great impact on the solar thermal collector efficiency. In this work, two coatings types were studied: coatings obtained by physical vapor deposition (PVDs) and coatings obtained by projection with different paints (PCs) ...

  7. High-quality PVD graphene growth by fullerene decomposition on Cu foils

    Czech Academy of Sciences Publication Activity Database

    Azpeitia, J.; Otero-Irurueta, G.; Palacio, I.; Martinez, J. I.; Ruiz del Arbol, N.; Santoro, G.; Gutiérrez, A.; Aballe, L.; Foerster, M.; Kalbáč, Martin; Valeš, Václav; Mompean, F. J.; Garcia-Hernandez, M.; Martín-Gago, J.A.; Munuera, C.; Lopez, M. F.

    2017-01-01

    Roč. 119, AUG 2017 (2017), s. 535-543 ISSN 0008-6223 R&D Projects: GA MŠk LL1301 EU Projects: European Commission(XE) 696656 - GrapheneCore1 Institutional support: RVO:61388955 Keywords : functional perturbation-theory * epitaxial graphene * copper substrate * pt(111) surface * raman-spectrum * cvd-graphene Subject RIV: CF - Physical ; Theoretical Chemistry OBOR OECD: Physical chemistry Impact factor: 6.337, year: 2016

  8. Characteristics of PVdF copolymer/Nafion blend membrane for direct methanol fuel cell (DMFC)

    International Nuclear Information System (INIS)

    Cho, Ki-Yun; Eom, Ji-Yong; Jung, Ho-Young; Choi, Nam-Soon; Lee, Yong Min; Park, Jung-Ki; Choi, Jong-Ho; Park, Kyung-Won; Sung, Yung-Eun

    2004-01-01

    For direct methanol fuel cell, blends of vinylidene fluoride-hexafluoropropylene copolymer (P(VdF-co-HFP)) and Nafion were prepared the different equivalent weight of Nafion. The investigations of the blend morphology were performed by means of permeability test, uptake measurement, differential-scanning calorimetry (DSC), and scanning electron microscopy. In the blend membranes, many pores were created as the content of Nafion in blend increased. Then, the methanol uptake was sharply increased. But the methanol permeability was not sharply increased because the methanol permeation through blend membranes is diffusion-controlled process. The methanol permeability of N10 (low equivalent weight) series was similar to that of N11 series (high equivalent weight). The proton conductivity of N10 series was around one and a half times higher than that of N11 series. The cell performance of the blend was much enhanced when the equivalent weight of Nafion was 1000

  9. Hemocompatibility of Inorganic Physical Vapor Deposition (PVD Coatings on Thermoplastic Polyurethane Polymers

    Directory of Open Access Journals (Sweden)

    Daniel Heim

    2012-04-01

    Full Text Available Biocompatibility improvements for blood contacting materials are of increasing interest for implanted devices and interventional tools. The current study focuses on inorganic (titanium, titanium nitride, titanium oxide as well as diamond-like carbon (DLC coating materials on polymer surfaces (thermoplastic polyurethane, deposited by magnetron sputtering und pulsed laser deposition at room temperature. DLC was used pure (a-C:H as well as doped with silicon, titanium, and nitrogen + titanium (a-C:H:Si, a-C:H:Ti, a-C:H:N:Ti. In-vitro testing of the hemocompatibility requires mandatory dynamic test conditions to simulate in-vivo conditions, e.g., realized by a cone-and-plate analyzer. In such tests, titanium- and nitrogen-doped DLC and titanium nitride were found to be optimally anti-thrombotic and better than state-of-the-art polyurethane polymers. This is mainly due to the low tendency to platelet microparticle formation, a high content of remaining platelets in the whole blood after testing and low concentration of platelet activation and aggregation markers. Comparing this result to shear-flow induced cell motility tests with e.g., Dictostelium discoideum cell model organism reveals similar tendencies for the investigated materials.

  10. PVD of copper sulfide (Cu2S) for PIN-structured solar cells

    International Nuclear Information System (INIS)

    Siol, Sebastian; Brötz, Joachim; Klein, Andreas; Jaegermann, Wolfram; Sträter, Hendrik; Brüggemann, Rudolf; Bauer, Gottfried H

    2013-01-01

    Thin layers of chalcocite (Cu 2 S) have been deposited via physical vapour deposition using various pre- and post-treatment parameters. The electrical and morphological properties have been investigated by in situ XPS, SEM and XRD measurements. Calibrated photoluminescence experiments were performed to investigate the material's suitability as an absorber layer in thin-film solar cells. Measurements of annealed Cu 2 S layers on glass without any surface passivation showed an optical band gap of 1.25 eV as well as a splitting of the quasi-Fermi levels of 710 meV. This value exceeds the highest reported open-circuit voltage for Cu 2 S-based devices so far, which leads to the assumption that Cu 2 S has not been brought to its full potential yet. The band alignments for ZnO/Cu 2 S as well as Cu 2 S/Cu 2 O interfaces have been determined using in situ XPS interface experiments to suggest a novel device structure according to the favourable PIN-layout. First devices have been built, but show no efficiency due to shunting caused by the inferior morphology of the absorber layers. (paper)

  11. Microstructure, composition and performance of PVD coatings designed for successful dry high speed milling

    International Nuclear Information System (INIS)

    Muenz, W.-D.; Lembke, M.I.; Lewis, D.B.; Smith, I.J.

    2001-01-01

    Dry high speed machining (HSM), particularly dry high speed milling, demands hard coatings, which exhibit high toughness, high oxidation resistance, a limited amount of residual stress and excellent adhesion to the cemented carbide (CC) substrate. These requirements are met by TiAICrYN coatings grown by the combined cathodic arc/unbalanced magnetron deposition method. Fully sufficient adhesion is achieved by ion implantation of Cr into the CC prior deposition. Residual stress is controlled by an Y - free base layer; high oxidation resistance is provided by an Y - containing 3 μm thick hard coating with 29 GPa hardness and a residual stress well below -7 GPa. Under the influence of temperatures above 800 o C, Y segregates along the columns of TiAIN and plugs the in/out diffusion of elements. A top layer of Y - containing oxynitride reduces the friction against the work piece material (0.9 to 0.65). Cutting tools coated as such may be used for dry milling up to 25 k rpm in steels HRC > 60. (author)

  12. Phase controlled synthesis and cathodoluminescence properties of ZnS nanobelts synthesized by PVD

    Science.gov (United States)

    Jin, Changqing; Zhu, Kexin; Peterson, George; Zhang, Zhihong; Jian, Zengyun; Wei, Yongxing; Zheng, Deshan

    2018-01-01

    Zinc sulfide (ZnS) nanobelts were synthesized via physical vapor deposition to explore the electronic properties of optoelectronic nano-devices. It was determined that the mass ratio of wurtzite (WZ) phase to zincblende (ZB) phase and the preferential orientation (100) are related to the carrier-gas flow rate. The high concentration of planar defects within the phase boundary enhances phase transition. Cathodoluminescence measurements show a red shift of the 337 nm band-gap emission due to stacking and twin faults. We find a direct correlation between the magnitude of the red shift and the mass ratio of ZB phase. With an increase in the ZB phase, there is an increase in the concentration of stacking and twin faults introduced by the phase transformation, as indicated by an increasing red shift in the data. The absorption peaks at 666 and 719 nm were found by UV-vis absorption spectrum, which is attributed to surface defects. This work would help to better understand the important roles of planar defects in the phase transition and also provide us with a feasible route to control phase ratio and cathodoluminescence properties of ZnS nanobelts and other II-VI semiconductor nanostructures.

  13. Magnesium substituted hydroxyapatite formation on (Ti,Mg)N coatings produced by cathodic arc PVD technique.

    Science.gov (United States)

    Onder, Sakip; Kok, Fatma Nese; Kazmanli, Kursat; Urgen, Mustafa

    2013-10-01

    In this study, formation of magnesium substituted hydroxyapatite (Ca10-xMgx(PO4)6(OH)2) on (Ti,Mg)N and TiN coating surfaces were investigated. The (Ti1-x,Mgx)N (x=0.064) coatings were deposited on titanium substrates by using cathodic arc physical vapor deposition technique. TiN coated grade 2 titanium substrates were used as reference to understand the role of magnesium on hydroxyapatite (HA) formation. The HA formation experiments was carried out in simulated body fluids (SBF) with three different concentrations (1X SBF, 5X SBF and 5X SBF without magnesium ions) at 37 °C. The coatings and hydroxyapatite films formed were characterized by scanning electron microscope (SEM), X-ray diffraction (XRD) and FTIR Spectroscopy techniques. The energy dispersive X-ray spectroscopy (EDS) analyses and XRD investigations of the coatings indicated that magnesium was incorporated in the TiN structure rather than forming a separate phase. The comparison between the TiN and (Ti, Mg)N coatings showed that the presence of magnesium in TiN structure facilitated magnesium substituted HA formation on the surface. The (Ti,Mg)N coatings can potentially be used to accelerate the HA formation in vivo conditions without any prior hydroxyapatite coating procedure. © 2013.

  14. Investigation of vanadium and nitride alloys thin layers deposited by PVD

    Directory of Open Access Journals (Sweden)

    Nouveau C.

    2012-06-01

    Full Text Available In this work we present the technique of magnetron vapor deposition and the effect of several deposition parameters on the structural and morphological properties of prepared thin films. It was noted that the deposition time has an effect on the crystallinity, mechanical properties such as residual stress, roughness surface and the layer composition from target products. Studies were carried out on layers of vanadium (V and the nitride vanadium (VN.

  15. RBS and XPS study of TiOx layers prepared by the PVD technique .

    Czech Academy of Sciences Publication Activity Database

    Macková, Anna; Peřina, Vratislav; Krumeich, J.; Zemek, J.; Kolouch, A.

    2004-01-01

    Roč. 36, č. 8 (2004), s. 1171-1173 ISSN 0142-2421 R&D Projects: GA ČR GP102/01/D069 Institutional research plan: CEZ:AV0Z1048901 Keywords : RBS * ERDA * TiOx Subject RIV: BM - Solid Matter Physics ; Magnetism Impact factor: 1.209, year: 2004

  16. Hemocompatibility of Inorganic Physical Vapor Deposition (PVD) Coatings on Thermoplastic Polyurethane Polymers.

    Science.gov (United States)

    Lackner, Juergen M; Waldhauser, Wolfgang; Hartmann, Paul; Bruckert, Franz; Weidenhaupt, Marianne; Major, Roman; Sanak, Marek; Wiesinger, Martin; Heim, Daniel

    2012-04-17

    Biocompatibility improvements for blood contacting materials are of increasing interest for implanted devices and interventional tools. The current study focuses on inorganic (titanium, titanium nitride, titanium oxide) as well as diamond-like carbon (DLC) coating materials on polymer surfaces (thermoplastic polyurethane), deposited by magnetron sputtering und pulsed laser deposition at room temperature. DLC was used pure (a-C:H) as well as doped with silicon, titanium, and nitrogen + titanium (a-C:H:Si, a-C:H:Ti, a-C:H:N:Ti). In-vitro testing of the hemocompatibility requires mandatory dynamic test conditions to simulate in-vivo conditions, e.g., realized by a cone-and-plate analyzer. In such tests, titanium- and nitrogen-doped DLC and titanium nitride were found to be optimally anti-thrombotic and better than state-of-the-art polyurethane polymers. This is mainly due to the low tendency to platelet microparticle formation, a high content of remaining platelets in the whole blood after testing and low concentration of platelet activation and aggregation markers. Comparing this result to shear-flow induced cell motility tests with e.g., Dictostelium discoideum cell model organism reveals similar tendencies for the investigated materials.

  17. High-quality PVD graphene growth by fullerene decomposition on Cu foils.

    Science.gov (United States)

    Azpeitia, J; Otero-Irurueta, G; Palacio, I; Martinez, J I; Del Árbol, N Ruiz; Santoro, G; Gutiérrez, A; Aballe, L; Foerster, M; Kalbac, M; Vales, V; Mompeán, F J; García-Hernández, M; Martín-Gago, J A; Munuera, C; López, M F

    2017-08-01

    We present a new protocol to grow large-area, high-quality single-layer graphene on Cu foils at relatively low temperatures. We use C 60 molecules evaporated in ultra high vacuum conditions as carbon source. This clean environment results in a strong reduction of oxygen-containing groups as depicted by X-ray photoelectron spectroscopy (XPS). Unzipping of C 60 is thermally promoted by annealing the substrate at 800ºC during evaporation. The graphene layer extends over areas larger than the Cu crystallite size, although it is changing its orientation with respect to the surface in the wrinkles and grain boundaries, producing a modulated ring in the low energy electron diffraction (LEED) pattern. This protocol is a self-limiting process leading exclusively to one single graphene layer. Raman spectroscopy confirms the high quality of the grown graphene. This layer exhibits an unperturbed Dirac-cone with a clear n-doping of 0.77 eV, which is caused by the interaction between graphene and substrate. Density functional theory (DFT) calculations show that this interaction can be induced by a coupling between graphene and substrate at specific points of the structure leading to a local sp 3 configuration, which also contribute to the D-band in the Raman spectra.

  18. Characterization of nano-composite PVD coatings for wear-resistant applications

    NARCIS (Netherlands)

    Galvan, D.; Pei, Y.T.; de Hosson, J.T.M.; DeHosson, JTM; Brebbia, CA; Nishida, SI

    2005-01-01

    Various methodologies for the characterization of nano-composite coatings are discussed, which consist TiC nano-particles distributed in an amorphous hydrocarbon (a-C:H) matrix. Complications that arise from the influence of coating roughness and underlying substrate on the properties are evaluated

  19. Evaluation of Antibacterial Activity of Titanium Surface Modified by PVD/PACVD Process.

    Science.gov (United States)

    Ji, Min-Kyung; Lee, Min-Joo; Park, Sang-Won; Lee, Kwangmin; Yun, Kwi-Dug; Kim, Hyun-Seung; Oh, Gye-Jeong; Kim, Ji-Hyun; Lim, Hyun-Pil

    2016-02-01

    The aim of this study was to evaluate the response of Streptococcus mutans (S. mutans) via crystal violet staining assay on titanium surface modified by physical vapor deposition/plasma assisted chemical vapor deposition process. Specimens were divided into the following three groups: polished titanium (control group), titanium modified by DC magnetron sputtering (group TiN-Ti), and titanium modified by plasma nitriding (group N-Ti). Surface characteristics of specimens were observed by using nanosurface 3D optical profiler and field emission scanning electron microscope. Group TiN-Ti showed TiN layer of 1.2 microm in thickness. Group N-Ti was identified as plasma nitriding with X-ray photoelectron spectroscopy. Roughness average (Ra) of all specimens had values 0.05). Within the process condition of this study, modified titanium surfaces by DC magnetron sputtering and plasma nitriding did not influence the adhesion of S. mutans.

  20. Metal nitride coatings by physical vapor deposition (PVD) for a wear resistant aluminum extrusion die.

    Science.gov (United States)

    Lee, Su Young; Kim, Sang Ho

    2014-12-01

    The purpose of this study is to investigate the friction and wear behaviors of CrN, TiN, CrAlN, and TiAIN coated onto SKD61 for application to Al 7000 series extrusion dies. On the wear test, the experimental parameters are the load and the counter material's temperature. The results showed that the friction coefficient increased with load but decreased with the counter material's temperature, and the friction coefficients of CrN and CrAIN were lower than the friction coefficients of TiAIN and TIN, especially at a higher temperature. The wear track with different coatings identified different wear behaviors; the wear behavior of CrAIN was found to be abrasive, but the wear behavior of TiN, CrN, and TiAIN was adhesive. Therefore, CrAIN showed the least wear loss with a lower friction coefficient and less adhesion with counter materials at the highest range of wear load and temperature. This resulted in the easy formation of aluminum oxide in the wear track and less Al adhesion; moreover during the hard second phase, AIN dispersed in the film during deposition.

  1. Kajian Aus Pahat pada pembubutan Baja Aisi 4340 Menggunakan Pahat Karbida PVD Berlapis

    OpenAIRE

    Carnegie, Dale

    2017-01-01

    120401084 Pada industri pemotongan logam, cairan pendingin banyak digunakan untuk memperoleh umur pahat yang lebih lama, tetapi cairan pendingin yang digunakan pada proses pemotongan logam mempunyai beberapa dampak negatif bagi kesehatan dan lingkungan. Oleh karena itu dilakukan permesinan kering pada penelitian ini untuk membuat proses pemotongan logam yang bersih dan aman terhadap lingkungan. Proses pembubutan dilakukan juga dengan permesinan keras untuk membubut material baja AISI 4340 ...

  2. Plasma analysis of different TiN PVD processes at various process parameters

    International Nuclear Information System (INIS)

    Strauss, G.N.; Schlichtherle, S.; Pulker, H.K.; Meyer, M.; Jehn, H.; Balzer, M.; Misiano, C.; Silipo, V.

    2002-01-01

    TiN coatings of some microns in thickness were deposited by different reactive plasma deposition technologies (Magnetron Sputtering Magnetically Assisted, Arc Source Ion Plating, Sputter Ion Plating Plasma Assisted) on various metal parts. The experiments were carried out in specially designed plants under variable vacuum and plasma conditions. The plasma properties of the different processes were investigated by mass spectrometry and the energy distribution of process relevant particles was additionally determined. The aim of this work was to find proper processes and conditions for a reliable low cost deposition of hard coatings at relatively high gas pressures. It was found that the magnetically forced and medium frequency pulsed biased dc magnetron sputter deposition variants, operating in the 10 -3 mbar gas pressure range, showed a relatively large amount of single and double charged positive ions with kinetic energies up to 55 and 95 eV, as consequence of the applied modifications. Cathodic arc deposition, in the same gas pressure range of 10 - 3 mbar, showed a very high number of such ions with energies up to more than 100 eV, depending on the value of the applied arc current. However, at constant distance between source and substrate the higher gas pressure increases also the number of energy reducing collisions of the coating-material vapour-species with the gas molecules. The arc source process, even when performed at high gas pressures of about 10 -1 mbar, showed a remarkable amount of ions with energies up to 75 eV resulting in high performance TiN films of quite proper 3D homogeneity. The arc source technique is able to increase film thickness uniformity up to 3 times with respect to the traditional coatings if the samples are mounted in a way that they do not influence each other. (nevyjel)

  3. Domino Platform: PVD Coaters for Arc Evaporation and High Current Pulsed Magnetron Sputtering

    International Nuclear Information System (INIS)

    Vetter, J; Müller, J; Erkens, G

    2012-01-01

    AlTiN and CrN coatings were deposited in hybrid DOMINO platforms by magnetron sputtering (DC-MS, DC-MS+HCP-MS, HCP-MS) and vacuum arc evaporation. The ion cleaning was done by the AEGD process. The coating rates and the energy efficiency of both deposition processes were compared. The roughness effects of the different coating types were discussed. Preliminary results of the change of pulse characteristics during simultaneously running of HCP-MS plus vacuum arc evaporation are shown.

  4. Ho:YAG laser: intervertebral disk cell interaction using three-dimensional cell culture system

    Science.gov (United States)

    Sato, Masato; Ishihara, Miya; Arai, Tsunenori; Asazuma, Takashi; Kikuchi, Toshiyuki; Kikuchi, Makoto; Fujikawa, Kyosuke

    2000-06-01

    The purpose of this study is to evaluate the influence on the intervertebral disc cells after laser irradiation using three- dimensional culture system and to clarify the optimum Ho:YAG laser irradiation condition on percutaneous laser disc decompression (PLDD) for lumbar disc herniation. Since the Ho:YAG laser ablation is characterized by water-vapor bubble dynamics, not only thermal effect but also acoustic effect on cell metabolism might occur in the intervertebral disc. We studied the disc cell reaction from the metabolic point of view to investigate photothermal and photoacoustic effects on three-dimensional cultured disc cell. Intervertebral discs were obtained from female 30 Japanese white rabbits weighing about 1 kg. A pulsed Ho:YAG laser (wavelength: 2.1 micrometer, pulse width: about 200 microseconds) was delivered through a 200 micrometer-core diameter single silica glass fiber. We used the Ho:YAG laser irradiation fluence ranging from 60 to approximately 800 J/cm2 at the fiber end. To investigate acoustic effect, the acoustic transducer constructed with polyvinylidene fluoride (PVdF) film and acoustic absorber was used to detect the stress wave. Thermocouple and thermography were used to investigate thermal effect. Concerning damage of plasma membrane and ability of matrix synthesis, thermal effect might mainly affect cell reaction in total energy of 54 J (closed to practically used condition), but in 27 J, acoustic effect might contribute to it. We found that total energy was key parameter among the optimum condition, so that temperature and/or stress wave may influence Ho:YAG laser-disc cell interactions.

  5. Effectiveness of intrauterine treatment with cephapirin in dairy cows with purulent vaginal discharge.

    Science.gov (United States)

    Tison, N; Bouchard, E; DesCôteaux, L; Lefebvre, R C

    2017-02-01

    The objective of this study was to assess the efficacy of cephapirin intrauterine treatment preceding a timed artificial insemination protocol in lactating dairy cows with purulent vaginal discharges (PVDs). Holstein dairy cows (n = 1247) from 18 herds were enrolled in a controlled randomized clinical trial. At 34 days in milk (DIM; ±7 days), cows had a genital examination (transrectal palpation, vaginoscopy, and uterine bacteriology). They were randomly assigned to either the control group (CONT, no treatment) or the treatment group (CEPH) consisting of 1 intrauterine infusion of 500-mg cephapirin benzathine (RCL) (Metricure, Merck Animal Health, Montreal, Canada) regardless of the uterine health status. All cows were systematically enrolled in a presynch-ovsynch protocol for the first insemination. A second genital examination was made 2 weeks later. Cows that received any systemic or local antibiotics 10 days prior sampling to the end of the synchronization protocol were excluded from the study. Reproductive data of cows were collected for at least 300 DIM, entered in a databank, and validated (health record management software, DSAHR). Pregnancy diagnosis was done by transrectal palpation at the routinely scheduled veterinarian visits. On the basis of the highest sum of sensibility and specificity for pregnancy status at 120 DIM, the optimal cutoff for vaginal discharge score was determined as the presence of cloudy discharge with or without purulent material (PVD+, score 2). With a prevalence of 21.6% at 34 DIM, PVD+ was detrimental to the first-service conception rate (FSCR; PVD+: 26 ± 5%; PVD-: 40 ± 3%; P = 0.02). The negative effect of PVD+ was indicated by a hazard ratio of 0.72 (chi-square = 8.58; P < 0.01; 95% confidence interval = 0.56-0.91). Treatment with cephapirin was associated with a significant improvement of the FSCR in PVD+ cows (PVD+ CEPH: 36 ± 5%, PVD+ CONT: 23 ± 5%; P < 0.05), although it did not produce a

  6. Data of evolutionary structure change: 1PVDB-2VBFA [Confc[Archive

    Lifescience Database Archive (English)

    Full Text Available 1PVDB-2VBFA 1PVD 2VBF B A SEITLGKYLFERLKQVNVNTVFGLPGDFNLSLLDKIYEV...ASYMADGYARTKKAAAFLTTFGVGELSAINGLAGSYAENLPVVEIVGSPTSKVQNDGKFVHHTLADGDFKHFMKMHEPVTAARTLLT-AENATYEIDRVLSQLLKERKPVYINLPVD...HHHHH 0 1PVD B 1PVDB KGYKP-VAVPA 1 1PVD B 1PVD

  7. System Budgets

    DEFF Research Database (Denmark)

    Jeppesen, Palle

    1996-01-01

    The lecture note is aimed at introducing system budgets for optical communication systems. It treats optical fiber communication systems (six generations), system design, bandwidth effects, other system impairments and optical amplifiers.......The lecture note is aimed at introducing system budgets for optical communication systems. It treats optical fiber communication systems (six generations), system design, bandwidth effects, other system impairments and optical amplifiers....

  8. Ventilation systems

    International Nuclear Information System (INIS)

    Gossler

    1980-01-01

    The present paper deals with - controlled area ventilation systems - ventilation systems for switchgear-building and control-room - other ventilation systems for safety equipments - service systems for ventilation systems. (orig./RW)

  9. Prevalence of systemic co-morbidities in patients with various grades of diabetic retinopathy

    Directory of Open Access Journals (Sweden)

    Pradeep Venkatesh

    2014-01-01

    Full Text Available Background & objectives : Though diabetes affects multiple organs, most studies highlight the occurence of only one complication in isolation. We conducted a hospital-based study to estimate the co-existence of significant systemic co-morbid conditions in patients with varying grades of diabetic retinopathy. Methods : A total of 170 consecutive patients with diabetic retinopathy were prospectively recruited for the study between June 2009 to June 2010 at a tertiary care eye centre in north India. Retinopathy was graded by fundus biomicroscopy and fundus photography and classified into three categories (mild-moderate nonproliferative retinopathy, proliferative retinopathy requiring only laser and proliferative retinopathy requiring surgery. Nephropathy was classified by calculating the six variable estimated glomerular filtration rate (eGFR for all patients. Nerve conduction studies and clinical assessment were used to determine presence of neuropathy. Co-existence of macrovascular disease and peripheral vascular disease was also ascertained. Results : The percentages of patients with overt nephropathy in the three groups were 19.2, 38.0 and 41.2, respectively. Significant linear trends were observed for serum creatinine (P=0.004, albumin (P=0.017 and eGFR (P=0.030. A higher per cent had abnormal nerve conduction on electrophysiology than that diagnosed clinically (65.4 vs. 44.2, 76.0 vs. 40.0 and 64.8 vs. 48.6, respectively. The odds ratio (95% CI for co-existence of nephropathy, neuropathy, CVA (cerebrovascular accidents and PVD (peripheral vascular disease was 2.9, 0.9, 4.8 and 3.5, respectively. Independent of retinopathy severity, patients with clinically significant macular oedema (CSME had a higher percentage of nephropathy ( p0 < 0.005. Interpretation & conclusions : The co-existence of overt nephropathy, nerve conduction based neuropathy and macrovascular co-morbidity in patients with early grades of diabetic retinopathy was significant

  10. Preparation, properties, and application characteristics of metastable layers of the Ti-Si-C-N system

    International Nuclear Information System (INIS)

    Fella, R.

    1992-10-01

    In the Ti-Si-C and Ti-Si-C-N systems, metastable layers were precipitated by means of non-reactive magnetron sputtering of hot-pressed two-phase TiC/SiC and TiN/SiC targets with 20 mole% and 50 mole% SiC. The preparation parameters were varied as follows: ion bombardment during precipitation (bias sputtering), substrate temperature, and annealing times when annealing amorphous 50%:50% TiC/SiC and 50%:50% TiN/SiC layers. Sputtering of targets containing 20% SiC was found to result in monophase fcc layers (NaCl structure). This was documented on the basis of X-ray and electron diffraction patterns. Direct precipitation of targets with 50 mole% SiC resulted in amorphous layers. Increasing the ion bombardment during accretion, raising the substrate temperature, and annealing amorphous 50%:50% TiC/SiC and 50%:50% TiN/SiC (layers precipitated directly) resulted in the crystallization of TiC and TiN nanocrystallites, respectively, imbedded in an amorphous SiC matrix. These crystallites were detected both by X-ray and by electron diffractions and by XPS studies. The XPS measurements of crystalline TiC and amorphous SiC reference layers demonstrated the existence of new kinds of carbon interface phases ('pseudocarbide layers') around TiC and amorphous SiC regions, respectively, which have a positive impact on the mechanical properties of the layers. The hardness of the layers can be correlated with the degrees of crystallization and texture. Adhesion and toughness are worse in SiC-bearing layers than PVD TiC and TiN layers, respectively. The application characteristics of the layers were determined by model wear tests relative to 100Cr6 by means of a pin/disk tribometer. N-bearing layers were found to have clearly higher friction coefficients and greater wear than layers without N. (orig.)

  11. An improvement of the GPS buoy system for detecting tsunami at far offshore

    Science.gov (United States)

    Kato, T.; Terada, Y.; Nagai, T.; Kawaguchi, K.; Koshimura, S.; Matsushita, Y.

    2012-12-01

    than 20km. This limits the lead time for letting coastal residents to evacuate from the coast only about 10 minutes after the detection of tsunami at a GPS buoy. This requires us to improve the system to put the buoy much farther from the coast. In order to solve this problem, we have introduced a new algorithm of precise point positioning with ambiguity resolution (PPP-AR) method and point precise variance detection (PVD) method for estimating the precise location of the buoy. As these method does not require land base station, it may allow us to deploy a buoy much farther than 100km offshore observation. Also, an open source program package (RTKLIB) is introduced for kinematic analysis for a long baseline. A new experiment using this system has started about 40km south off Cape Muroto in April 2012. One of buoys called as "Kuroshio Bokujo", which is used as a fish bed by Kochi Prefecture, is used for this purpose. The positioning results are exhibited in real time on the internet.

  12. Embedded Systems

    Indian Academy of Sciences (India)

    Embedded system, micro-con- troller ... Embedded systems differ from general purpose computers in many ... Low cost: As embedded systems are extensively used in con- .... operating systems for the desktop computers where scheduling.

  13. Development and Performance Evaluations of HfO2-Si and Rare Earth-Si Based Environmental Barrier Bond Coat Systems for SiC/SiC Ceramic Matrix Composites

    Science.gov (United States)

    Zhu, Dongming

    2014-01-01

    Ceramic environmental barrier coatings (EBC) and SiCSiC ceramic matrix composites (CMCs) will play a crucial role in future aircraft propulsion systems because of their ability to significantly increase engine operating temperatures, improve component durability, reduce engine weight and cooling requirements. Advanced EBC systems for SiCSiC CMC turbine and combustor hot section components are currently being developed to meet future turbine engine emission and performance goals. One of the significant material development challenges for the high temperature CMC components is to develop prime-reliant, high strength and high temperature capable environmental barrier coating bond coat systems, since the current silicon bond coat cannot meet the advanced EBC-CMC temperature and stability requirements. In this paper, advanced NASA HfO2-Si based EBC bond coat systems for SiCSiC CMC combustor and turbine airfoil applications are investigated. The coating design approach and stability requirements are specifically emphasized, with the development and implementation focusing on Plasma Sprayed (PS) and Electron Beam-Physic Vapor Deposited (EB-PVD) coating systems and the composition optimizations. High temperature properties of the HfO2-Si based bond coat systems, including the strength, fracture toughness, creep resistance, and oxidation resistance were evaluated in the temperature range of 1200 to 1500 C. Thermal gradient heat flux low cycle fatigue and furnace cyclic oxidation durability tests were also performed at temperatures up to 1500 C. The coating strength improvements, degradation and failure modes of the environmental barrier coating bond coat systems on SiCSiC CMCs tested in simulated stress-environment interactions are briefly discussed and supported by modeling. The performance enhancements of the HfO2-Si bond coat systems with rare earth element dopants and rare earth-silicon based bond coats are also highlighted. The advanced bond coat systems, when

  14. Thermal systems; Systemes thermiques

    Energy Technology Data Exchange (ETDEWEB)

    Lalot, S. [Valenciennes Univ. et du Hainaut Cambresis, LME, 59 (France); Lecoeuche, S. [Ecole des Mines de Douai, Dept. GIP, 59 - Douai (France)]|[Lille Univ. des Sciences et Technologies, 59 - Villeneuve d' Ascq (France); Ahmad, M.; Sallee, H.; Quenard, D. [CSTB, 38 - Saint Martin d' Heres (France); Bontemps, A. [Universite Joseph Fourier, LEGI/GRETh, 38 - Grenoble (France); Gascoin, N.; Gillard, P.; Bernard, S. [Laboratoire d' Energetique, Explosion, Structure, 18 - Bourges (France); Gascoin, N.; Toure, Y. [Laboratoire Vision et Robotique, 18 - Bourges (France); Daniau, E.; Bouchez, M. [MBDA, 18 - Bourges (France); Dobrovicescu, A.; Stanciu, D. [Bucarest Univ. Polytechnique, Faculte de Genie Mecanique (Romania); Stoian, M. [Reims Univ. Champagne Ardenne, Faculte des Sciences, UTAP/LTM, 51 (France); Bruch, A.; Fourmigue, J.F.; Colasson, S. [CEA Grenoble, Lab. Greth, 38 (France); Bontemps, A. [Universite Joseph Fourier, LEGI/GRETh, 38 - Grenoble (France); Voicu, I.; Mare, T.; Miriel, J. [Institut National des Sciences Appliquees (INSA), LGCGM, IUT, 35 - Rennes (France); Galanis, N. [Sherbrooke Univ., Genie Mecanique, QC (Canada); Nemer, M.; Clodic, D. [Ecole des Mines de Paris, Centre Energetique et Procedes, 75 (France); Lasbet, Y.; Auvity, B.; Castelain, C.; Peerhossaini, H. [Nantes Univ., Ecole Polytechnique, Lab. de Thermocinetiquede Nantes, UMR-CNRS 6607, 44 (France)

    2005-07-01

    This session about thermal systems gathers 26 articles dealing with: neural model of a compact heat exchanger; experimental study and numerical simulation of the thermal behaviour of test-cells with walls made of a combination of phase change materials and super-insulating materials; hydraulic and thermal modeling of a supercritical fluid with pyrolysis inside a heated channel: pre-dimensioning of an experimental study; energy analysis of the heat recovery devices of a cryogenic system; numerical simulation of the thermo-hydraulic behaviour of a supercritical CO{sub 2} flow inside a vertical tube; mixed convection inside dual-tube exchangers; development of a nodal approach with homogenization for the simulation of the brazing cycle of a heat exchanger; chaotic exchanger for the cooling of low temperature fuel cells; structural optimization of the internal fins of a cylindrical generator; a new experimental approach for the study of the local boiling inside the channels of exchangers with plates and fins; experimental study of the flow regimes of boiling hydrocarbons on a bundle of staggered tubes; energy study of heat recovery exchangers used in Claude-type refrigerating systems; general model of Carnot engine submitted to various operating constraints; the free pistons Stirling cogeneration system; natural gas supplied cogeneration system with polymer membrane fuel cell; influence of the CRN coating on the heat flux inside the tool during the wood unrolling process; transport and mixture of a passive scalar injected inside the wake of a Ahmed body; control of a laser welding-brazing process by infrared thermography; 2D self-adaptative method for contours detection: application to the images of an aniso-thermal jet; exergy and exergy-economical study of an 'Ericsson' engine-based micro-cogeneration system; simplified air-conditioning of telephone switching equipments; parametric study of the 'low-energy' individual dwelling; brief synthesis of

  15. Electrochemical investigation of surface area effects on PVD Al-Ni as electrocatalyst for alkaline water electrolysis

    DEFF Research Database (Denmark)

    Kjartansdóttir, Cecilía Kristín; Caspersen, Michael; Egelund, Sune Daaskov

    2014-01-01

    , additional 40mV are gained. For the OER, smaller roughness values were observed with the same activity trend as for the HER. The electrocatalyst are however found not to be stable in the anodic environment during electrolysis. The corrosion mechanism of a skeletal nickel electrocatalyst during the OER...

  16. Mechanical and Tribological Properties of PVD-Coated Cemented Carbide as Evaluated by a New Multipass Scratch-Testing Method

    Directory of Open Access Journals (Sweden)

    M. Fallqvist

    2012-01-01

    Full Text Available A new test method based on multipass scratch testing has been developed for evaluating the mechanical and tribological properties of thin, hard coatings. The proposed test method uses a pin-on-disc tribometer and during testing a Rockwell C diamond stylus is used as the “pin” and loaded against the rotating coated sample. The influence of normal load on the number of cycles to coating damage is investigated and the resulting coating damage mechanisms are evaluated by posttest scanning electron microscopy. The present study presents the test method by evaluating the performance of Ti0.86Si0.14N, Ti0.34Al0.66N, and (Al0.7Cr0.32O3 coatings deposited by cathodic arc evaporation on cemented carbide inserts. The results show that the test method is quick, simple, and reproducible and can preferably be used to obtain relevant data concerning the fatigue, wear, chipping, and spalling characteristics of different coating-substrate composites. The test method can be used as a virtually nondestructive test and, for example, be used to evaluate the fatigue and wear resistance as well as the cohesive and adhesive interfacial strength of coated cemented carbide inserts prior to cutting tests.

  17. Numerical and Experimental Investigations of the Effect of PVD and Vacuum Pressure on the Degree of Saturation

    Directory of Open Access Journals (Sweden)

    Ala Nasir Aljorany

    2018-12-01

    Full Text Available Soft clays are generally characterized by low shear strength, low permeability and high compressibility. An effective method to accelerate consolidation of such soils is to use vertical drains along with vacuum preloading to encourage radial flow of water. In this research numerical modeling of prefabricated vertical drains with vacuum pressure was done to investigate the effect of using vertical drains together with vacuum pressure on the degree of saturation of fully and saturated-unsaturated soft soils. Laboratory experiments were conducted by using a specially-designed large consolidometer cell where a central drain was installed and vacuum pressure was applied. All tests were conducted with a vacuum pressure of 40 kPa applied for a period of 30 days where a degree of soil consolidation of 90% was attained. At the end of the test period fifteen samples were taken from different locations distributed along the depth and radially to measure the water content. Consolidation settlements were recorded with time for all tests. The results showed that using vacuum pressure with vertical drains is a very effective method to accelerate consolidation of soils. As the thickness of unsaturated top layer increases, the settlement of soil surface decreases. The water content decreased after 30 days of application of the vacuum pressure.

  18. Failure characteristics and mechanisms of EB-PVD TBCs with Pt-modified NiAl bond coats

    Energy Technology Data Exchange (ETDEWEB)

    Zhou, Le; Mukherjee, Sriparna; Huang, Ke; Park, Young Whan; Sohn, Yongho, E-mail: Yongho.Sohn@ucf.edu

    2015-06-18

    Microstructural evolution and failure characteristics/mechanisms were investigated for thermal barrier coatings that consist of electron beam physical vapor deposited ZrO{sub 2}−8 wt% Y{sub 2}O{sub 3} (YSZ) topcoat, Pt-modified nickel aluminide, (Ni,Pt)Al bond coat, and CMSX-4 superalloy substrate with furnace cycling at 1100 °C with 1-h dwell. Photo stimulated luminescence spectroscopy, scanning electron microscopy equipped with X-ray energy dispersive spectroscopy and transmission electron microscopy were employed to examine the residual stress of the thermally grown oxide (TGO) and microstructural changes. For comparison, (Ni,Pt)Al bond coat on CMSX-4 without the YSZ topcoat was also characterized. The TGO grew faster for the YSZ-coated (Ni,Pt)Al bond coat than the (Ni,Pt)Al coating without the YSZ topcoat. Correspondingly, the β-to-γ′/martensite formation in the (Ni,Pt)Al bond coat occurred faster on the YSZ-coated (Ni,Pt)Al bond coat. However the rumpling occurred much faster and with larger amplitude on the (Ni,Pt)Al coating without the YSZ topcoat. Still, the rumpling at the TGO/bond coat interface caused crack initiation as early as 10 thermal cycles, decohesion at the YSZ/TGO interface, and eventual spallation failure primarily through the TGO/bond coat interface. The magnitude of compressive residual stress in the TGO showed an initial increase up to 3−4 GPa followed by a gradual decrease. The rate of stress relaxation was much quicker for the TGO scale without the YSZ topcoat with distinctive relief corresponding to the cracking at the top of geometrical ridges associated with the (Ni,Pt)Al bond coat. The maximum elastic energy for the TGO scale was estimated at 90 J/m{sup 2} at 50% of its lifetime (N{sub f}=545 cycles). The YSZ presence/adhesion to the TGO scale is emphasized to minimize the undulation of the TGO/bond coat interface, i.e., decohesion at the YSZ/TGO scale accelerates the rumpling and crack-coalescence at the TGO/bond coat interface where the spallation fracture occurs.

  19. Non-destructive evaluation of degradation in EB-PVD thermal barrier coatings by infrared reflectance spectroscopy

    International Nuclear Information System (INIS)

    Flattum, Richard Y.; Cooney, Adam T.

    2013-01-01

    At room temperature and atmospheric conditions infrared reflectance spectroscopy and X-ray diffraction were employed for the detection of the phase transformation and residual stress within thermal barrier coatings (TBC). The TBC's samples initially consisted of the porous ceramic topcoat deposited by electron beam plasma vapor deposition, a bond coat and a superalloy substrate. Reflectance spectroscopy scans were performed from 7497 cm −1 to 68 cm −1 to analysis the fingerprint region as well as the chemical bonding region. These regions should indicate if a detectable change within the TBC response is a result of thermal degradation of the microstructure and the changes in yttrium dispersion throughout the yttrium stabilized zirconium. The thermal degradation was induced by thermal cycling the samples to 1100° C and then cooling them in an atmospheric environment. X-ray diffraction was also used to detect the phase composition within the TBC samples and see if either would clearly identify failure prior to actual spallation. The eventual measurability and quantify-ability of the phase changes within the TBC's may be used as an effective non-destructive evaluation (NDE) technique that would allow personnel in the field to know when servicing of the turbine blade was necessary.

  20. Nanostructured MgTiO{sub 3} thick films obtained by electrophoretic deposition from nanopowders prepared by solar PVD

    Energy Technology Data Exchange (ETDEWEB)

    Apostol, Irina [S.C. IPEE Amiral Trading Impex S.A., 115300 Curtea de Arges (Romania); Mahajan, Amit [Department of Materials and Ceramics Engineering, Centre for Research in Ceramics and Composite Materials, CICECO, University of Aveiro, 3810-093 Aveiro (Portugal); Monty, Claude J.A. [CNRS-PROMES Laboratory, 66120 Font Romeu Odeillo (France); Venkata Saravanan, K., E-mail: venketvs@cutn.ac.in [Department of Materials and Ceramics Engineering, Centre for Research in Ceramics and Composite Materials, CICECO, University of Aveiro, 3810-093 Aveiro (Portugal); Department of Physics, School of Basic and Applied Science, Central University of Tamil Nadu, Thiruvarur 61010 (India)

    2015-12-15

    Highlights: • Obtaining nano-crystalline magnesium titanium oxide powders by solar physical vapor deposition (SPVD) process. And using these nano-powders to obtain thick films on conducting substrates by electrophoretic deposition (EPD). • SPVD is a core innovative, original and environmentally friendly process to prepare nano-materials in a powder form. • Sintered thick films exhibited dielectric constant, ε{sub r} ∼18.3 and dielectric loss, tan δ ∼0.0012 at 1 MHz, which is comparable to the values reported earlier. • New contributions to the pool of information on the preparation of nano-structured MgTiO{sub 3} thick films at low temperatures. • A considerable decrease in synthesis temperature of pure MgTiO{sub 3} thick film was observed by the combination of SPVD and EPD. - Abstract: A novel combination of solar physical vapor deposition (SPVD) and electrophoretic deposition (EPD) that was developed to grow MgTiO{sub 3} nanostructured thick films is presented. Obtaining nanostructured MgTiO{sub 3} thick films, which can replace bulk ceramic components, a major trend in electronic industry, is the main objective of this work. The advantage of SPVD is direct synthesis of nanopowders, while EPD is simple, fast and inexpensive technique for preparing thick films. SPVD technique was developed at CNRS-PROMES Laboratory, Odeillo-Font Romeu, France, while the EPD was performed at University of Aveiro – DeMAC/CICECO, Portugal. The nanopowders with an average crystallite size of about 30 nm prepared by SPVD were dispersed in 50 ml of acetone in basic media with addition of triethanolamine. The obtained well-dispersed and stable suspensions were used for carrying out EPD on 25 μm thick platinum foils. After deposition, films with thickness of about 22–25 μm were sintered in air for 15 min at 800, 900 and 1000 °C. The structural and microstructural characterization of the sintered thick films was carried out using XRD and SEM, respectively. The thickness of the sintered samples were about 18–20 μm, which was determined by cross-sectional SEM. Films sintered at 900 °C exhibit a dielectric constant, ε{sub r} ∼18.3 and dielectric loss, tan δ ∼0.0012 at 1 MHz. The effects of processing techniques (SPVD and EPD) on the structure, microstructure and dielectric properties are reported in detail. The obtained results indicate that the thick films obtained in the present study can be promising for low loss materials for microwave and millimeter wave applications.

  1. Adhesion Strength of TiN Coatings at Various Ion Etching Deposited on Tool Steels Using Cathodic Arc Pvd Technique

    Science.gov (United States)

    Ali, Mubarak; Hamzah, Esah; Ali, Nouman

    Titanium nitride (TiN) widely used as hard coating material was coated on tool steels, namely on high-speed steel (HSS) and D2 tool steel by physical vapor deposition method. The goal of this study was to examine the effect of ion etching with and without titanium (Ti) and chromium (Cr) on the adhesion strength of TiN coatings deposited on tool steels. From the scratch tester, it was observed that by increasing Ti ion etching showed an increase in adhesion strength of the deposited coatings. The coatings deposited with Cr ion etching showed poor adhesion compared with the coatings deposited with Ti ion etching. Scratch test measurements showed that the coating deposited with titanium ion etching for 16 min is the most stable coating and maintained even at the critical load of 66 N. The curve obtained via penetration depth along the scratch trace is linear in the case of HSS, whereas is slightly flexible in the case of D2 tool steel. The coatings deposited on HSS exhibit better adhesion compared with those on D2 tool steel.

  2. Study of PVD AlCrN Coating for Reducing Carbide Cutting Tool Deterioration in the Machining of Titanium Alloys.

    Science.gov (United States)

    Cadena, Natalia L; Cue-Sampedro, Rodrigo; Siller, Héctor R; Arizmendi-Morquecho, Ana M; Rivera-Solorio, Carlos I; Di-Nardo, Santiago

    2013-05-24

    The manufacture of medical and aerospace components made of titanium alloys and other difficult-to-cut materials requires the parallel development of high performance cutting tools coated with materials capable of enhanced tribological and resistance properties. In this matter, a thin nanocomposite film made out of AlCrN (aluminum-chromium-nitride) was studied in this research, showing experimental work in the deposition process and its characterization. A heat-treated monolayer coating, competitive with other coatings in the machining of titanium alloys, was analyzed. Different analysis and characterizations were performed on the manufactured coating by scanning electron microscopy and energy-dispersive X-ray spectroscopy (SEM-EDXS), and X-ray diffraction (XRD). Furthermore, the mechanical behavior of the coating was evaluated through hardness test and tribology with pin-on-disk to quantify friction coefficient and wear rate. Finally, machinability tests using coated tungsten carbide cutting tools were executed in order to determine its performance through wear resistance, which is a key issue of cutting tools in high-end cutting at elevated temperatures. It was demonstrated that the specimen (with lower friction coefficient than previous research) is more efficient in machinability tests in Ti6Al4V alloys. Furthermore, the heat-treated monolayer coating presented better performance in comparison with a conventional monolayer of AlCrN coating.

  3. Lithium Ion Transport Across and Between Phase Boundaries in Heterogeneous Polymer Electrolytes, Based on PVdF

    National Research Council Canada - National Science Library

    Greenbaum, Steven

    1998-01-01

    .... In the first reported attempt to exploit 17O NMR to study lithium battery electrolytes, we have prepared 17O-enriched Li triflate and several electrolytes containing the isotopically enriched salt...

  4. The Effect of Annealing on the Structural and Optical Properties of Titanium Dioxide Films Deposited by Electron Beam Assisted PVD

    Directory of Open Access Journals (Sweden)

    Yaser M. Abdulraheem

    2013-01-01

    Full Text Available Titanium dioxide thin films were deposited on crystalline silicon substrates by electron beam physical vapor deposition. The deposition was performed under vacuum ranging from 10−5 to 10−6 Torr without process gases, resulting in homogeneous TiO2-x layers with a thickness of around 100 nm. Samples were then annealed at high temperatures ranging from 500°C to 800°C for 4 hours under nitrogen, and their structural and optical properties along with their chemical structure were characterized before and after annealing. The chemical and structural characterization revealed a substoichiometric TiO2-x film with oxygen vacancies, voids, and an interface oxide layer. It was found from X-ray diffraction that the deposited films were amorphous and crystallization to anatase phase occurred for annealed samples and was more pronounced for annealing temperatures above 700°C. The refractive index obtained through spectroscopic ellipsometry ranged between 2.09 and 2.37 in the wavelength range, 900 nm to 400 nm for the as-deposited sample, and jumped to the range between 2.23 and 2.65 for samples annealed at 800°C. The minimum surface reflectance changed from around 0.6% for the as-deposited samples to 2.5% for the samples annealed at 800°C.

  5. A Comparison of Afghanistan, Yuma, Az, and Manufactured Sands Melted on EB-PVD Thermal Barrier Coatings

    Science.gov (United States)

    2014-09-18

    mentoring me through the field of geology . His vast knowledge in this field and close “First Cousins” motivate me to broaden my knowledge within the...Blade sand sample BC – Bond Coat Button A – TBC Button made by Manufacturer A Button B – TBC Button made by Manufacturer B Ca – Calcium CMAS... Calcium , Magnesium, Aluminum, Silicate CTIO – Coating Technology Integration Office Cr – Chromium CTE – Coefficient of Thermal Expansion DoD

  6. Effect of PS-PVD production throughput on Si nanoparticles for negative electrode of lithium ion batteries

    Science.gov (United States)

    Ohta, R.; Fukada, K.; Tashiro, T.; Dougakiuchi, M.; Kambara, M.

    2018-03-01

    Silicon nanoparticles (Si-NPs) have been produced by plasma spray physical vapor deposition at throughput as high as 1 kg h-1 (17 g min-1) and the effect on the battery performance is investigated. When the Si powder feed-rate is changed from 1 to 17 g min-1, although the average primary particle size increases to 50 nm, the cycle capacity of the batteries using these Si-NPs is improved slightly owing to their less agglomerated structure. In contrast, when Ni is added to Si feedstock, the cycle capacity is improved at 1 g min-1 due to modified Si-NP structure having SiNi2 interface. Whereas, the batteries with the Si-NP produced at 17 g min-1 shows significant decrease in the cycle capacity because of the excess Ni silicide formation that is resulted from the elevated co-condensation point and the increased reaction area at high throughputs despite the constant Ni concentration in the feedstock.

  7. Van stichtelijke fraseologie naar redelijkheid. De PvdA en de oorlog in Vietnam, 1964-1973

    Directory of Open Access Journals (Sweden)

    F. Zuijdam

    2002-01-01

    Full Text Available The Dutch Labour Party and the war in VietnamDuring the 1960s, many people demonstrated against the war in Vietnam. However, the Dutch government, along with most of the major political parties in the Netherlands, chose to ignore the vox populi and refused to reject America's policy regarding Vietnam. One exception to that rule was the Dutch Labour Party. From an early stage, the social-democrats had kept a critical watch on American policy and exhibited an increasing resistance to the subsequent military intervention. In adopting this attitude towards the Vietnam War, the Labour Party had to take several developments into account. The reduction in Cold War tensions, the Cultural Revolution and, above all, the shifts in domestic politics all affected the point of view on Vietnam. One very important consideration that should be taken into account was that, at the time, the Labour Party was trapped between new forms of activism and firm opposition, on the one hand, and the wish to join the government on the other. Under these circumstances, a formal letter to the American Ambassador seemed to be the safest vehicle through which Labour's critical attitude towards Vietnam could be expressed.

  8. A novel anti-frictional multiphase layer produced by plasma nitriding of PVD titanium coated ZL205A aluminum alloy

    Science.gov (United States)

    Lu, C.; Yao, J. W.; Wang, Y. X.; Zhu, Y. D.; Guo, J. H.; Wang, Y.; Fu, H. Y.; Chen, Z. B.; Yan, M. F.

    2018-02-01

    The heat treatment (consisting of solid solution and aging), is integrated with the nitriding process of titanium coated ZL205A aluminum alloy to improve the surface and matrix mechanical properties simultaneously. Two-step duplex treatment is adopted to prepare the gradient multiphase layer on a magnesium-free ZL205A aluminum-copper based alloy. Firstly, pure titanium film is deposited on the aluminum alloy substrate using magnetron sputtering. Secondly, the Ti-coated specimen is nitrided at the solid solution temperature of the substrate alloying elements in a gas mixture of N2 and H2 and aged at 175 °C. The microstructure evolution, microhardness as well as the wear resistance of obtained multiphase layers are investigated by means of scanning electron microscopy (SEM) equipped with energy dispersive X-ray spectrometer (EDS), microhardness tester and pin-on-disc tribometer. The multiphase layer, dominated by TiN0.3 or Al3Ti, is prepared with significantly increased layer depth after duplex treatment. The surface hardness of multiphase layer is remarkably improved from 23.7HV to 457HV. The core matrix hardness is also increased to 65HV after aging. The wear rate of the multiphase layer decreases about 55.22% and 49.28% in comparison with the aged and Ti coated specimens, respectively. The predominant wear mechanism for the multiphase layer is abrasive and oxidation, but severe adhesive wear for the aged and Ti coated specimens.

  9. Modelling the growth of ZnO thin films by PVD methods and the effects of post-annealing.

    Science.gov (United States)

    Blackwell, Sabrina; Smith, Roger; Kenny, Steven D; Walls, John M; Sanz-Navarro, Carlos F

    2013-04-03

    Results are presented for modelling of the evaporation and magnetron sputter deposition of Zn(x)O(y) onto an O-terminated ZnO (0001¯) wurtzite surface. Growth was simulated through a combination of molecular dynamics (MD) and an on-the-fly kinetic Monte Carlo (otf-KMC) method, which finds diffusion pathways and barriers without prior knowledge of transitions. We examine the effects of varying experimental parameters, such as substrate bias, distribution of the deposition species and annealing temperature. It was found when comparing evaporation and sputtering growth that the latter process results in a denser and more crystalline structure, due to the higher deposition energy of the arriving species. The evaporation growth also exhibits more stacking faults than the sputtered growth. Post-annealing at 770 K did not allow complete recrystallization, resulting in films which still had stacking faults where monolayers formed in the zinc blende phase, whereas annealing at 920 K enabled the complete recrystallization of some films to the wurtzite structure. At the latter temperature atoms could also sometimes be locked in the zinc blende phase after annealing. When full recrystallization did not take place, both wurtzite and zinc blende phases were seen in the same layer, resulting in a phase boundary. Investigation of the various distributions of deposition species showed that, during evaporation, the best quality film resulted from a stoichiometric distribution where only ZnO clusters were deposited. During sputtering, however, the best quality film resulted from a slightly O rich distribution. Two stoichiometric distributions, one involving mainly ZnO clusters and the other involving mainly single species, showed that the distribution of deposition species makes a huge impact on the grown film. The deposition of predominantly single species causes many more O atoms at the surface to be sputtered or reflected, resulting in an O deficiency of up to 18% in the deposited film and therefore resulting in more stacking faults and phase boundaries. The methods used allow analysis of key mechanisms that occur during the growth process and give hints as to the optimum conditions under which complete crystalline layers can form.

  10. Histopathological Evaluation of a Hydrophobic Terpolymer (PTFE-PVD-PP) as an Implant Material for Nonpenetrating Very Deep Sclerectomy.

    Science.gov (United States)

    Leszczynski, Rafal; Gumula, Teresa; Stodolak-Zych, Ewa; Pawlicki, Krzysztof; Wieczorek, Jaroslaw; Kajor, Maciej; Blazewicz, Stanislaw

    2015-08-01

    The purpose of the study was to assess the biocompatibility of porous terpolymer (polytetrafluoroethylene-co-polyvinylidene fluoride-co-polypropylene, PTFE-PVDF-PP) membranes as an implant material to be placed during nonpenetrating very deep sclerectomy (NPVDS). Another study objective was to determine whether the polymer membrane under investigation could be used to manufacture a new-generation implant, which would actively delay the process of fistula closure and facilitate aqueous humor drainage. Histological response and tissue tolerance of the implant material were assessed. The study was performed on 38 eyeballs of 19 New Zealand white rabbits (19 implanted, 19 control). Histological assessment was carried out between 2 and 52 weeks after surgery. We routinely assessed inflammatory infiltrate, neovascularization, hemorrhage, and stromal edema as well as connective tissue attachment to the implant and adjacent tissues. At 52 weeks of observation, a statistically significant difference was revealed between the study and control groups in terms of resorptive granulation, tissue, and the inflammatory infiltrate. No features of acute inflammatory response to the implant were observed, and there was an absence of histological features of acute inflammatory infiltrates and subsidence of chronic inflammatory infiltrates and resorptive granulation over time. Slight fibrotic response and insignificant changes in neighboring eye tissues all indicate good tolerance to bioimplant materials. This allows for some optimism regarding the use of hydrophobic terpolymer in the construction of new intrascleral implants. However, the ultimate decision regarding its usefulness and safety in the treatment of glaucoma requires further investigation.

  11. On the Electrochemical Behavior of PVD Ti-Coated AISI 304 Stainless Steel in Borate Buffer Solution

    Science.gov (United States)

    Fattah-alhosseini, Arash; Elmkhah, Hassan; Attarzadeh, Farid Reza

    2017-04-01

    This work aims at studying the electrochemical behavior of annealed pure titanium (Ti) and nano-structured (NS) Ti coating in borate buffer solutions. Cathodic arc evaporation was successfully applied to deposit NS Ti coating. Samples were characterized by means of scanning electron microscope and x-ray diffraction. Potentiodynamic polarization tests, electrochemical impedance spectroscopy, and Mott-Schottky analysis were employed to discuss the electrochemical behavior of samples thoroughly. Electrochemical measurements showed that the deposited NS Ti coating offers a superior passivity in borate buffer solutions of pH 9.0 and 9.5. Mott-Schottky analysis revealed that all passive films are of n-type semiconducting nature in these alkaline solutions and the deposition process did not alter the semiconducting type of passive films formed on samples. Additionally, this analysis showed that the NS Ti coating possessed lower levels of donor densities. Finally, all electrochemical tests showed that passive behavior of the NS Ti samples was superior, mainly due to the formation of thicker and less defective passive films.

  12. Effect of substrate bias on structure and properties of the TiN coatings obtained in the PVD process

    International Nuclear Information System (INIS)

    Dobrzanski, L.A.; Kwasny, W.

    2003-01-01

    The paper presents investigation results of the field of deposition parameters on structure and mechanical properties of the TiN coatings obtained by magnetron sputtering in the vacuum furnace onto the ASP 30 sintered high speed steel. Effect of sputtering parameters on chemical and phase composition, thickness, microhardness and roughness parameter. The characteristic structure and surface topography of the analyzed coatings are presented. (author)

  13. Data Systems vs. Information Systems

    OpenAIRE

    Amatayakul, Margret K.

    1982-01-01

    This paper examines the current status of “hospital information systems” with respect to the distinction between data systems and information systems. It is proposed that the systems currently existing are incomplete data dystems resulting in ineffective information systems.

  14. SiC/GaN Based Optically Triggered MESFET for High Power Efficiency and High Radiation Resistance Solid State Switch Application for Actuator System

    Science.gov (United States)

    2016-06-23

    designed and nitrogen ion implantation has been performed followed by high temperature annealing . In 2016, the device electrical isolation has been...sputtering physical vapor deposition (PVD). The SiO2 layers were grown onto C-face and Si-face 4H-SiC substrates by different techniques such as wet ...forming the source and drain contact by ion implantation, (ii) the rapid thermal annealing processing, (iii) device isolation by using ion implantation

  15. EXPERT SYSTEMS

    OpenAIRE

    Georgiana Marin; Mihai Catalin Andrei

    2011-01-01

    In recent decades IT and computer systems have evolved rapidly in economic informatics field. The goal is to create user friendly information systems that respond promptly and accurately to requests. Informatics systems evolved into decision assisted systems, and such systems are converted, based on gained experience, in expert systems for creative problem solving that an organization is facing. Expert systems are aimed at rebuilding human reasoning on the expertise obtained from experts, sto...

  16. Multibody Systems

    DEFF Research Database (Denmark)

    Wagner, Falko Jens

    1999-01-01

    Multibody Systems is one area, in which methods for solving DAEs are of special interst. This chapter is about multibody systems, why they result in DAE systems and what kind of problems that can arise when dealing with multibody systems and formulating their corresponding DAE system....

  17. Nanostructured Coatings with Self-Healing and Temperature Homogenization Functions for High Temperature Sliding Interfaces

    Science.gov (United States)

    2010-10-01

    showing the stainless steel chamber (A), the rotatable substrate holder (B), the plasma burning between substrate holder and magnetrons (C) and three...Final Report University of Leoben, Austria 3 The sputtering system consists of a cylindrical stainless steel chamber (Ø 380 x 235mm) (A) which...Si (100), AISI M2 steel and Fe substrates. The tribological performance of these coatings has been compared to undoped ZrO2 thin films in a

  18. System dynamics

    International Nuclear Information System (INIS)

    Kim, Do Hun; Mun, Tae Hun; Kim, Dong Hwan

    1999-02-01

    This book introduces systems thinking and conceptual tool and modeling tool of dynamics system such as tragedy of single thinking, accessible way of system dynamics, feedback structure and causal loop diagram analysis, basic of system dynamics modeling, causal loop diagram and system dynamics modeling, information delay modeling, discovery and application for policy, modeling of crisis of agricultural and stock breeding products, dynamic model and lesson in ecosystem, development and decadence of cites and innovation of education forward system thinking.

  19. Classification of posterior vitreous detachment

    Science.gov (United States)

    Kakehashi, Akihiro; Takezawa, Mikiko; Akiba, Jun

    2014-01-01

    Diagnosing a posterior vitreous detachment (PVD) is important for predicting the prognosis and determining the indication for vitreoretinal surgery in many vitreoretinal diseases. This article presents both classifications of a PVD by slit-lamp biomicroscopy and of a shallow PVD by optical coherence tomography (OCT). By biomicroscopy, the vitreous condition is determined based on the presence or absence of a PVD. The PVD then is classified as either a complete posterior vitreous detachment (C-PVD) or a partial posterior vitreous detachment (P-PVD). A C-PVD is further divided into a C-PVD with collapse and a C-PVD without collapse, while a P-PVD is divided into a P-PVD with shrinkage of the posterior hyaloid membrane (P-PVD with shrinkage) and a P-PVD without shrinkage of the posterior hyaloid membrane (P-PVD without shrinkage). A P-PVD without shrinkage has a subtype characterized by vitreous gel attachment through the premacular hole in a posterior hyaloid membrane to the macula (P-PVD without shrinkage [M]). By OCT, a shallow PVD is classified as the absence of a shallow PVD or as a shallow PVD. A shallow PVD is then subclassified as a shallow PVD without shrinkage of the posterior vitreous cortex, a shallow PVD with shrinkage of the posterior vitreous cortex, and a peripheral shallow PVD. A shallow PVD without shrinkage of the posterior vitreous cortex has two subtypes: an age-related shallow PVD and a perifoveal PVD associated with a macular hole. PMID:24376338

  20. Coupling component systems towards systems of systems

    OpenAIRE

    Autran , Frédéric; Auzelle , Jean-Philippe; Cattan , Denise; Garnier , Jean-Luc; Luzeaux , Dominique; Mayer , Frédérique; Peyrichon , Marc; Ruault , Jean-René

    2008-01-01

    International audience; Systems of systems (SoS) are a hot topic in our "fully connected global world". Our aim is not to provide another definition of what SoS are, but rather to focus on the adequacy of reusing standard system architecting techniques within this approach in order to improve performance, fault detection and safety issues in large-scale coupled systems that definitely qualify as SoS, whatever the definition is. A key issue will be to secure the availability of the services pr...

  1. Systems effectiveness

    CERN Document Server

    Habayeb, A R

    1987-01-01

    Highlights three principal applications of system effectiveness: hardware system evaluation, organizational development and evaluation, and conflict analysis. The text emphasizes the commonality of the system effectiveness discipline. The first part of the work presents a framework for system effectiveness, partitioning and hierarchy of hardware systems. The second part covers the structure, hierarchy, states, functions and activities of organizations. Contains an extended Appendix on mathematical concepts and also several project suggestions.

  2. Auxiliary systems

    International Nuclear Information System (INIS)

    Meyer, P.J.

    1981-01-01

    Systems included under the heading ''Reactor Auxillary Systems'' are those immediately involved with the reactor operation. These include the systems for dosing and letdown of reactor coolant, as well as for the chemical dosing, purification and treatment of the reactor coolant and the cooling system in the controlled area. The ancillary systems are mainly responsible for liquid and gaseous treatment and the waste treatment for final storage. (orig.)

  3. RAB-10 Regulates Dendritic Branching by Balancing Dendritic Transport

    Science.gov (United States)

    Taylor, Caitlin A.; Yan, Jing; Howell, Audrey S.; Dong, Xintong; Shen, Kang

    2015-01-01

    The construction of a large dendritic arbor requires robust growth and the precise delivery of membrane and protein cargoes to specific subcellular regions of the developing dendrite. How the microtubule-based vesicular trafficking and sorting systems are regulated to distribute these dendritic development factors throughout the dendrite is not well understood. Here we identify the small GTPase RAB-10 and the exocyst complex as critical regulators of dendrite morphogenesis and patterning in the C. elegans sensory neuron PVD. In rab-10 mutants, PVD dendritic branches are reduced in the posterior region of the cell but are excessive in the distal anterior region of the cell. We also demonstrate that the dendritic branch distribution within PVD depends on the balance between the molecular motors kinesin-1/UNC-116 and dynein, and we propose that RAB-10 regulates dendrite morphology by balancing the activity of these motors to appropriately distribute branching factors, including the transmembrane receptor DMA-1. PMID:26633194

  4. Diffusion barriers of Al2O3 to reduce the bondcoat-oxidation of MCrAlY alloys

    International Nuclear Information System (INIS)

    Schmitt-Thomas, K.G.; Dietl, U.

    1992-01-01

    Under operating conditions in gas turbines plasma sprayed MCrAlY bondcoats (M = Co and/or Ni) for thermal barrier coatings are exposed to a strong oxidation attack. One possibility to reduce bondcoat oxidation is the application of diffusion barriers. Onto the bondcoat, diffusion barriers of Al 2 O 3 are deposited by CVD, PVD and plasma pulse process. The oxidation behaviour of these coating systems were examined at a temperature of 1273 K for times up to 250 hours. The CVD and PVD Al 2 O 3 - coated specimens show compared to the uncoated specimens smaller oxidation rates. The porous Al 2 O 3 coatings, produced by plasma pulse process are not fit for oxidation protection of the bondcoat. There is hope for further improvement of the oxidation resistance by optimizing the CVD- and PVD-process parameters. (orig.) [de

  5. Bitcoin System

    Directory of Open Access Journals (Sweden)

    Jan Lánský

    2017-06-01

    Full Text Available Cryptocurrency systems are purely digital and decentralized systems that use cryptographic principles to confirm transactions. Bitcoin is the first and also the most widespread cryptocurrency. The aim of this article is to introduce Bitcoin system using a language understandable also to readers without computer science education. This article captures the Bitcoin system from three perspectives: internal structure, network and users. Emphasis is placed on brief and clear definitions (system components and their mutual relationships. A new system view of the stated terms constitutes author’s own contribution.

  6. Galvanostatic methods for stripping of crn coatings; Estudio para la recuperacion de herramientas recubiertas con nitrogeno de cromo mediante ensayos galvanostaticos

    Energy Technology Data Exchange (ETDEWEB)

    Cristobal, A. B.; Conde, A.; Rodriguez, R.; Fuentes, G. G.; Montala, F.; Carreras, L.; Damborenea, J. de

    2006-07-01

    The improvements of the corrosion, wear and tribological behaviour by searching for new materials has entailed a greater expansion of PVD technology. Introduction of PVD systems in the industry is a real fact because this technique has been able to develop coatings whose response for many applications goes beyond used them until now. However the evolution of this technology requires minimize the economic costs in order to be a competitive process. A way to achieve this objective consists on recover the tool when the life time of the coating has finished or when deposition process has failed. (Author)

  7. JOSHUA system

    International Nuclear Information System (INIS)

    Honeck, H.C.

    1975-04-01

    A major computational system called JOSHUA has been under development at the Savannah River Laboratory since 1968. The JOSHUA System has two major parts: the Operating System and the Application System. The Operating System has been in production use since 1970 and provides data management, terminal, and job execution facilities. The Application System uses these facilities in solving problems in reactor physics and engineering. Features of the Application System are the two-dimensional lattice physics and three-dimensional transient reactor physics capabilities, which have been in use since 1971 and 1974, respectively. The capabilities of the JOSHUA System are summarized, and statistics on size, use, and development effort are provided. (U.S.)

  8. Systems thinking.

    Science.gov (United States)

    Cabrera, Derek; Colosi, Laura; Lobdell, Claire

    2008-08-01

    Evaluation is one of many fields where "systems thinking" is popular and is said to hold great promise. However, there is disagreement about what constitutes systems thinking. Its meaning is ambiguous, and systems scholars have made diverse and divergent attempts to describe it. Alternative origins include: von Bertalanffy, Aristotle, Lao Tsu or multiple aperiodic "waves." Some scholars describe it as synonymous with systems sciences (i.e., nonlinear dynamics, complexity, chaos). Others view it as taxonomy-a laundry list of systems approaches. Within so much noise, it is often difficult for evaluators to find the systems thinking signal. Recent work in systems thinking describes it as an emergent property of four simple conceptual patterns (rules). For an evaluator to become a "systems thinker", he or she need not spend years learning many methods or nonlinear sciences. Instead, with some practice, one can learn to apply these four simple rules to existing evaluation knowledge with transformative results.

  9. Cognitive Systems

    DEFF Research Database (Denmark)

    The tutorial will discuss the definition of cognitive systems as the possibilities to extend the current systems engineering paradigm in order to perceive, learn, reason and interact robustly in open-ended changing environments. I will also address cognitive systems in a historical perspective...... to be modeled within a limited set of predefined specifications. There will inevitably be a need for robust decisions and behaviors in novel situations that include handling of conflicts and ambiguities based on the capability and knowledge of the artificial cognitive system. Further, there is a need...... in cognitive systems include e.g. personalized information systems, sensor network systems, social dynamics system and Web2.0, and cognitive components analysis. I will use example from our own research and link to other research activities....

  10. Crystal Systems.

    Science.gov (United States)

    Schomaker, Verner; Lingafelter, E. C.

    1985-01-01

    Discusses characteristics of crystal systems, comparing (in table format) crystal systems with lattice types, number of restrictions, nature of the restrictions, and other lattices that can accidently show the same metrical symmetry. (JN)

  11. Filter systems

    International Nuclear Information System (INIS)

    Vanin, V.R.

    1990-01-01

    The multidetector systems for high resolution gamma spectroscopy are presented. The observable parameters for identifying nuclides produced simultaneously in the reaction are analysed discussing the efficiency of filter systems. (M.C.K.)

  12. Data of evolutionary structure change: 1PVDA-2VBIA [Confc[Archive

    Lifescience Database Archive (English)

    Full Text Available 1PVDA-2VBIA 1PVD 2VBI A A SEITLGKYLFERLKQVNVNTVFGLPGDFNLSLLDKIYEVEGMRWAGNANELNAAYAADGYARIKGMSCIITTFGVGELSALNGIAGSYAEHVG.../ss_2> 0 1PVD A 1PVDA SFNDN-SKIRM HHH ... 1PVD A 1PVD...A 233 ARG CA 308 GLN CA 388 1PVD

  13. Data of evolutionary structure change: 1PVDB-1ZPDB [Confc[Archive

    Lifescience Database Archive (English)

    Full Text Available 1PVDB-1ZPDB 1PVD 1ZPD B B SEITLGKYLFERLKQVNVNTVFGLPGDFNLSLLDKIYEVEGMRWAGNANELNAAYAADGYARIKGMSCIITTFGVGELSALNGIAGSYAEHVG...ex>0 1PVD B 1PVDB 1 1PVD B 1PVDB 1PVD B 1PVDB KLLQ...n14> 1PVD B 1PVDB

  14. Expert systems

    International Nuclear Information System (INIS)

    Haldy, P.A.

    1988-01-01

    The definitions of the terms 'artificial intelligence' and 'expert systems', the methodology, areas of employment and limits of expert systems are discussed. The operation of an expert system is described, especially the presentation and organization of knowledge as well as interference and control. Methods and tools for expert system development are presented and their application in nuclear energy are briefly addressed. 7 figs., 2 tabs., 6 refs

  15. Expert System

    DEFF Research Database (Denmark)

    Hildebrandt, Thomas Troels; Cattani, Gian Luca

    2016-01-01

    An expert system is a computer system for inferring knowledge from a knowledge base, typically by using a set of inference rules. When the concept of expert systems was introduced at Stanford University in the early 1970s, the knowledge base was an unstructured set of facts. Today the knowledge b...... for the application of expert systems, but also raises issues regarding privacy and legal liability....

  16. Retrofitting Systems

    DEFF Research Database (Denmark)

    Rose, Jørgen

    1997-01-01

    This report gives an overview of the different retrofitting possibilities that are available today. The report looks at both external and internal systems for external wall constructions, roof constructions, floor constructions and foundations. All systems are described in detail in respect to use...... and methods, and the efficiency of the different systems are discussed....

  17. Multifunction system

    International Nuclear Information System (INIS)

    Wauthier, J.; Fiori, R.

    1990-01-01

    The development, the characteristics and the applications of a multifunction system are presented. The system is used on the RBES laboratory pipes, at Marcoule. The system was developed in order to allow, without time loss, the modification of the circuit function by replacing only one component. The following elements form the multifunction system: a fixed base, which is part of the tube, a removable piece, which is inserted into the base, a cover plate and its locking system. The material, chosen among commercial trade marks, required small modifications in order to be used in the circuit [fr

  18. Operating systems

    CERN Document Server

    Tsichritzis, Dionysios C; Rheinboldt, Werner

    1974-01-01

    Operating Systems deals with the fundamental concepts and principles that govern the behavior of operating systems. Many issues regarding the structure of operating systems, including the problems of managing processes, processors, and memory, are examined. Various aspects of operating systems are also discussed, from input-output and files to security, protection, reliability, design methods, performance evaluation, and implementation methods.Comprised of 10 chapters, this volume begins with an overview of what constitutes an operating system, followed by a discussion on the definition and pr

  19. The primary vascular dysregulation syndrome: implications for eye diseases

    Science.gov (United States)

    2013-01-01

    Vascular dysregulation refers to the regulation of blood flow that is not adapted to the needs of the respective tissue. We distinguish primary vascular dysregulation (PVD, formerly called vasospastic syndrome) and secondary vascular dysregulation (SVD). Subjects with PVD tend to have cold extremities, low blood pressure, reduced feeling of thirst, altered drug sensitivity, increased pain sensitivity, prolonged sleep onset time, altered gene expression in the lymphocytes, signs of oxidative stress, slightly increased endothelin-1 plasma level, low body mass index and often diffuse and fluctuating visual field defects. Coldness, emotional or mechanical stress and starving can provoke symptoms. Virtually all organs, particularly the eye, can be involved. In subjects with PVD, retinal vessels are stiffer and more irregular, and both neurovascular coupling and autoregulation capacity are reduced while retinal venous pressure is often increased. Subjects with PVD have increased risk for normal-tension glaucoma, optic nerve compartment syndrome, central serous choroidopathy, Susac syndrome, retinal artery and vein occlusions and anterior ischaemic neuropathy without atherosclerosis. Further characteristics are their weaker blood–brain and blood-retinal barriers and the higher prevalence of optic disc haemorrhages and activated astrocytes. Subjects with PVD tend to suffer more often from tinnitus, muscle cramps, migraine with aura and silent myocardial ischaemic and are at greater risk for altitude sickness. While the main cause of vascular dysregulation is vascular endotheliopathy, dysfunction of the autonomic nervous system is also involved. In contrast, SVD occurs in the context of other diseases such as multiple sclerosis, retrobulbar neuritis, rheumatoid arthritis, fibromyalgia and giant cell arteritis. Taking into consideration the high prevalence of PVD in the population and potentially linked pathologies, in the current article, the authors provide

  20. New pulmonary vein Doppler echocardiographic index predicts significant interatrial shunting in secundum atrial septal defect.

    Science.gov (United States)

    Lam, Yat-Yin; Fang, Fang; Yip, Gabriel Wai-Kwok; Li, Zhi-An; Yang, Ya; Yu, Cheuk-Man

    2012-09-20

    The relation between pulmonary venous flow (PVF) pattern and degree of left-to-right interatrial shunting (IAS) in patients with secundum atrial septal defect (ASD) is unknown. Fifty consecutive ASD patients (14 males, 36 ± 17 years) received transthoracic echocardiography (TTE) before and 1 day after transcatheter closure and their results were compared to 40 controls. The ratio of pulmonary-to-systemic flows (Qp/Qs) was assessed by TTE and invasive oximetry. Pre-closure PV systolic (PVs), diastolic (PVd) velocities and velocity-time integral (PV-VTI) increased, time from onset of ECG Q-wave to the peak PV diastolic wave (Q-PVd) shortened and atrial reversal (PVar) velocity significantly decreased as compared to normals. These findings normalized after closure. Patients with large IAS (defined as invasive Qp/Qs ≥ 2) had higher PVs, PVd and PV-VTI, shorter Q-PVd but lower PVar (all pIAS. Invasive Qp/Qs ratios correlated with PVs, PVd, PV-VTI, Q-PVd and TTE-derived Qp/Qs ratios, ASD sizes and RV end-diastolic dimensions (all pIAS after multivariate analysis. The corresponding sensitivity, specificity and AUC were 89%, 82% and 0.90 respectively for a PV-VTI of 30 cm (pIAS have distinguishable PVF features. Doppler evaluation of PV-VTI is a novel additional tool for assessing the magnitude of shunting in these patients non-invasively. Copyright © 2011 Elsevier Ireland Ltd. All rights reserved.

  1. Systems integration.

    Science.gov (United States)

    Siemieniuch, C E; Sinclair, M A

    2006-01-01

    The paper presents a view of systems integration, from an ergonomics/human factors perspective, emphasising the process of systems integration as is carried out by humans. The first section discusses some of the fundamental issues in systems integration, such as the significance of systems boundaries, systems lifecycle and systems entropy, issues arising from complexity, the implications of systems immortality, and so on. The next section outlines various generic processes for executing systems integration, to act as guides for practitioners. These address both the design of the system to be integrated and the preparation of the wider system in which the integration will occur. Then the next section outlines some of the human-specific issues that would need to be addressed in such processes; for example, indeterminacy and incompleteness, the prediction of human reliability, workload issues, extended situation awareness, and knowledge lifecycle management. For all of these, suggestions and further readings are proposed. Finally, the conclusions section reiterates in condensed form the major issues arising from the above.

  2. Ternary systems

    International Nuclear Information System (INIS)

    Kagan, D.N.; Hubberstey, P.; Barker, M.G.

    1985-01-01

    The paper reviews the experimental and theoretical studies carried out on multicomponent alkali metal systems. Solid-liquid phase equilibria studies are mainly concerned with the systems Na-K-Rb and Na-K-Cs, and data on the liquidus temperatures in these systems are presented. The thermodynamic properties of the ternary Na-K-Cs eutectic system have been determined experimentally, and the enthalpy, heat capacity and excess functions of the alloy are given. An analysis of calculational methods used in determining thermodynamic functions of ternary liquid metals systems is described. Finally, data are tabulated for the density, compressibility, saturated vapour pressure, viscosity and thermal conductivity of the ternary Na-K-Cs eutectic system. (UK)

  3. Recommender systems

    CERN Document Server

    Kembellec, Gérald; Saleh, Imad

    2014-01-01

    Acclaimed by various content platforms (books, music, movies) and auction sites online, recommendation systems are key elements of digital strategies. If development was originally intended for the performance of information systems, the issues are now massively moved on logical optimization of the customer relationship, with the main objective to maximize potential sales. On the transdisciplinary approach, engines and recommender systems brings together contributions linking information science and communications, marketing, sociology, mathematics and computing. It deals with the understan

  4. Material Systems

    DEFF Research Database (Denmark)

    Jensen, Mads Brath; Mortensen, Henrik Rubæk; Mullins, Michael

    2009-01-01

    This paper describes and reflects upon the results of an investigative project which explores the setting up of a material system - a parametric and generative assembly consisting of and taking into consideration material properties, manufacturing constraints and geometric behavior. The project...... approaches the subject through the construction of a logic-driven system aiming to explore the possibilities of a material system that fulfills spatial, structural and performative requirements concurrently and how these are negotiated in situations where they might be conflicting....

  5. Systems Engineering

    OpenAIRE

    Vaughan, William W.

    2016-01-01

    The term “systems engineering” when entered into the Google search page, produces a significant number of results, evidence that systems engineering is recognized as being important for the success of essentially all products. Since most readers of this item will be rather well versed in documents concerning systems engineering, I have elected to share some of the points made on this subject in a document developed by the European Cooperation for Space Standardization (ECSS), a component of t...

  6. Energetic Systems

    Data.gov (United States)

    Federal Laboratory Consortium — The Energetic Systems Division provides full-spectrum energetic engineering services (project management, design, analysis, production support, in-service support,...

  7. Intelligent systems

    CERN Document Server

    Irwin, J David

    2011-01-01

    Technology has now progressed to the point that intelligent systems are replacing humans in the decision making processes as well as aiding in the solution of very complex problems. In many cases intelligent systems are already outperforming human activities. Artificial neural networks are not only capable of learning how to classify patterns, such images or sequence of events, but they can also effectively model complex nonlinear systems. Their ability to classify sequences of events is probably more popular in industrial applications where there is an inherent need to model nonlinear system

  8. Systemic darwinism.

    Science.gov (United States)

    Winther, Rasmus Grønfeldt

    2008-08-19

    Darwin's 19th century evolutionary theory of descent with modification through natural selection opened up a multidimensional and integrative conceptual space for biology. We explore three dimensions of this space: explanatory pattern, levels of selection, and degree of difference among units of the same type. Each dimension is defined by a respective pair of poles: law and narrative explanation, organismic and hierarchical selection, and variational and essentialist thinking. As a consequence of conceptual debates in the 20th century biological sciences, the poles of each pair came to be seen as mutually exclusive opposites. A significant amount of 21st century research focuses on systems (e.g., genomic, cellular, organismic, and ecological/global). Systemic Darwinism is emerging in this context. It follows a "compositional paradigm" according to which complex systems and their hierarchical networks of parts are the focus of biological investigation. Through the investigation of systems, Systemic Darwinism promises to reintegrate each dimension of Darwin's original logical space. Moreover, this ideally and potentially unified theory of biological ontology coordinates and integrates a plurality of mathematical biological theories (e.g., self-organization/structure, cladistics/history, and evolutionary genetics/function). Integrative Systemic Darwinism requires communal articulation from a plurality of perspectives. Although it is more general than these, it draws on previous advances in Systems Theory, Systems Biology, and Hierarchy Theory. Systemic Darwinism would greatly further bioengineering research and would provide a significantly deeper and more critical understanding of biological reality.

  9. Effects of exogenous pyoverdines on Fe availability and their impacts on Mn(II) oxidation by Pseudomonas putida GB-1

    Science.gov (United States)

    Lee, Sung-Woo; Parker, Dorothy L.; Geszvain, Kati; Tebo, Bradley M.

    2014-01-01

    Pseudomonas putida GB-1 is a Mn(II)-oxidizing bacterium that produces pyoverdine-type siderophores (PVDs), which facilitate the uptake of Fe(III) but also influence MnO2 formation. Recently, a non-ribosomal peptide synthetase mutant that does not synthesize PVD was described. Here we identified a gene encoding the PVDGB-1 (PVD produced by strain GB-1) uptake receptor (PputGB1_4082) of strain GB-1 and confirmed its function by in-frame mutagenesis. Growth and other physiological responses of these two mutants and of wild type were compared during cultivation in the presence of three chemically distinct sets of PVDs (siderotypes n°1, n°2, and n°4) derived from various pseudomonads. Under iron-limiting conditions, Fe(III) complexes of various siderotype n°1 PVDs (including PVDGB-1) allowed growth of wild type and the synthetase mutant, but not the receptor mutant, confirming that iron uptake with any tested siderotype n°1 PVD depended on PputGB1_4082. Fe(III) complexes of a siderotype n°2 PVD were not utilized by any strain and strongly induced PVD synthesis. In contrast, Fe(III) complexes of siderotype n°4 PVDs promoted the growth of all three strains and did not induce PVD synthesis by the wild type, implying these complexes were utilized for iron uptake independent of PputGB1_4082. These differing properties of the three PVD types provided a way to differentiate between effects on MnO2 formation that resulted from iron limitation and others that required participation of the PVDGB-1 receptor. Specifically, MnO2 production was inhibited by siderotype n°1 but not n°4 PVDs indicating PVD synthesis or PputGB1_4082 involvement rather than iron-limitation caused the inhibition. In contrast, iron limitation was sufficient to explain the inhibition of Mn(II) oxidation by siderotype n°2 PVDs. Collectively, our results provide insight into how competition for iron via siderophores influences growth, iron nutrition and MnO2 formation in more complex environmental

  10. Caste System

    OpenAIRE

    Hoff, Karla

    2016-01-01

    In standard economics, individuals are rational actors and economic forces undermine institutions that impose large inefficiencies. The persistence of the caste system is evidence of the need for psychologically more realistic models of decision-making in economics. The caste system divides South Asian society into hereditary groups whose lowest ranks are represented as innately polluted. ...

  11. Recommender systems

    OpenAIRE

    Lu L.; Medo M.; Yeung C.H.; Zhang Y.-C.; Zhang Z.-K.; Zhou T.

    2012-01-01

    The ongoing rapid expansion of the Internet greatly increases the necessity of effective recommender systems for filtering the abundant information. Extensive research for recommender systems is conducted by a broad range of communities including social and computer scientists, physicists, and interdisciplinary researchers. Despite substantial theoretical and practical achievements, unification and comparison of different approaches are lacking, which impedes further advances. In this article...

  12. GEOMASS system

    International Nuclear Information System (INIS)

    Ohyama, Takuya; Saegusa, Hiromitsu

    2009-03-01

    As a part of the research and development regarding characterisation of deep geological environment, the GEOMASS (GEOLOGICAL MODELLING ANALYSIS AND SIMULATION SOFTWARE) system has been developed by the Japan Atomic Energy Agency in order to carry out geological and hydrogeological modelling and groundwater flow simulation and so on. The GEOMASS system integrates a commercial geological interpretation system (EarthVision), which is used for geological modelling and visualisation, with a proprietary code for groundwater flow (FracAffinity). This integrated system allows users to make rapid improvement of models as data increases. Also, it is possible to perform more realistic groundwater flow simulation due to the capability of modelling the rock mass as a continuum with discrete hydro-structural features in the rock mass. This paper consists of 'Overview of GEOMASS system', FracAffinity Theoretical Background' and 'FracAffinity User Guide' and is edited as a GEOMASS system manual. 'Overview of GEOMASS system' describes the outline of this system. 'FracAffinity Theoretical Background' describes the information of technical background of FracAffinity software. FracAffinity User Guide' describes the structure of the FracAffinity input files, the usage of FracAffinity Interface and flow-solver. Updating of the FracAffinity has been continued as needed and FracAffinity version3.3 is the latest version at present (July 2008). (author)

  13. Systems integration (automation system). System integration (automation system)

    Energy Technology Data Exchange (ETDEWEB)

    Fujii, K; Komori, T; Fukuma, Y; Oikawa, M [Nippon Steal Corp., Tokyo (Japan)

    1991-09-26

    This paper introduces business activities on an automation systems integration (SI) started by a company in July,1988, and describes the SI concepts. The business activities include, with the CIM (unified production carried out on computers) and AMENITY (living environment) as the mainstays, a single responsibility construction ranging from consultation on structuring optimal systems for processing and assembling industries and intelligent buildings to system design, installation and after-sales services. With an SI standing on users {prime} position taken most importantly, the business starts from a planning and consultation under close coordination. On the conceptual basis of structuring optimal systems using the ompany {prime}s affluent know-hows and tools and adapting and applying with multi-vendors, open networks, centralized and distributed systems, the business is promoted with the accumulated technologies capable of realizing artificial intelligence and neural networks in its background, and supported with highly valuable business results in the past. 10 figs., 1 tab.

  14. Creative Systems

    DEFF Research Database (Denmark)

    Manelius, Anne-Mette; Beim, Anne

    2007-01-01

    Opsamling af diskussioner på konferencen og udstillingen Creative Systems i september/oktober 2007. Konferencen og Udstillingen Creative Systems sætter fokus på systemer som en positiv drivkraft i den kreative skabelsesproces. CINARK inviterede fire internationale kapaciteter, som indenfor hver...... deres felt har beskæftiget sig med udviklingen af systemer. Kieran Timberlake, markant amerikansk tegnestue; Mark West, Professor på University of Manitoba, Canada, og pioner indenfor anvendelse af tekstilforskalling til betonstøbninger; Matilda McQuaid, Arkitekturhistoriker og kurator på udstillingen...... om Extreme Textiles på amerikanske Cooper Hewit Design Museum, samt Professor Ludger Hovestadt, ved ETH, Zürich der fokuserer på udvikling og anvendelse af logaritmiske systemtilgange. Udstillingen diskuterede ud fra deres meget forskellige arbejder, det kreative potentiale i anvendelsen af systemer...

  15. Reactive Systems

    DEFF Research Database (Denmark)

    Aceto, Luca; Ingolfsdottir, Anna; Larsen, Kim Guldstrand

    A reactive system comprises networks of computing components, achieving their goals through interaction among themselves and their environment. Thus even relatively small systems may exhibit unexpectedly complex behaviours. As moreover reactive systems are often used in safety critical systems......, the need for mathematically based formal methodology is increasingly important. There are many books that look at particular methodologies for such systems. This book offers a more balanced introduction for graduate students and describes the various approaches, their strengths and weaknesses, and when...... they are best used. Milner's CCS and its operational semantics are introduced, together with the notions of behavioural equivalences based on bisimulation techniques and with recursive extensions of Hennessy-Milner logic. In the second part of the book, the presented theories are extended to take timing issues...

  16. Upgraded RECOVER system - CASDAC system

    International Nuclear Information System (INIS)

    Yamamoto, Yoichi; Koyama, Kinji

    1992-03-01

    The CASDAC (Containment And Surveillance Data Authenticated Communication) system has been developed by JAERI for nuclear safeguards and physical protection of nuclear material. This system was designed and constructed as an upgraded RECOVER system, design concept of which was based on the original RECOVER system and also the TRANSEAVER system. Both of them were developed several years ago as a remote monitoring system for continual verification of security and safeguards status of nuclear material. The system consists of two subsystems, one of them is a Grand Command Center (GCC) subsystem and the other is a facility subsystem. Communication between the two subsystems is controlled through the international telephone line network. Therefore all communication data are encrypted to prevent access by an unauthorized person who may intend to make a falsification, or tapping. The facility subsystem has an appropriate measure that ensure data security and reliable operation under unattended mode of operator. The software of this system is designed so as to be easily used in other different types of computers. This report describes the outline of the CASDAC system and the results of its performance test. This work has been carried out in the framework of Japan Support Programme for Agency Safeguards (JASPAS) as a project, JA-1. (author)

  17. Data of evolutionary structure change: 1PVDA-1ZPDE [Confc[Archive

    Lifescience Database Archive (English)

    Full Text Available 1PVDA-1ZPDE 1PVD 1ZPD A E SEITLGKYLFERLKQVNVNTVFGLPGDFNLSLLDKIYEV...HHHHH--HHHHH EEEEE HHHHHHHHHHHHHHH 0 1PVD... A 1PVDA KSFND-NSKIR ALA CA 225 SER CA 274 1PVD... A 1PVDA AKLLQTPID

  18. Data of evolutionary structure change: 1PVDA-2VBFB [Confc[Archive

    Lifescience Database Archive (English)

    Full Text Available 1PVDA-2VBFB 1PVD 2VBF A B SEITLGKYLFERLKQVNVNTVFGLPGDFNLSLLDKIYEV...LNASYMADGYARTKKAAAFLTTFGVGELSAINGLAGSYAENLPVVEIVGSPTSKVQNDGKFVHHTLADGDFKHFMKMHEPVTAARTLLT-AENATYEIDRVLSQLLKERKPVYINLPVD...2> 0 1PVD A 1PVDA KGYKP-VAVPA - 1 1PVD A

  19. Data of evolutionary structure change: 1PVDB-2NXWB [Confc[Archive

    Lifescience Database Archive (English)

    Full Text Available 1PVDB-2NXWB 1PVD 2NXW B B SEITLGKYLFERLKQVNVNTVFGLPGDFNLSLLDKIYEV...SSTLGVAAVTYGAGAFNMVNAVAGAYAEKSPVVVISGAPGTTELLD------TQFQVFKEITVAQARLDDPAKAPAEIARVLGAARAQSRPVYLEIPRNMVNAEVE------PVGDDPAWPVD...ID> 0 1PVD B 1PVDB 1.6429469585418701 1 1PVD... B 1PVDB EQHPR-YGGVY<

  20. Data of evolutionary structure change: 1PVDB-2VBFB [Confc[Archive

    Lifescience Database Archive (English)

    Full Text Available 1PVDB-2VBFB 1PVD 2VBF B B SEITLGKYLFERLKQVNVNTVFGLPGDFNLSLLDKIYEV...ASYMADGYARTKKAAAFLTTFGVGELSAINGLAGSYAENLPVVEIVGSPTSKVQNDGKFVHHTLADGDFKHFMKMHEPVTAARTLLT-AENATYEIDRVLSQLLKERKPVYINLPVD.../ss_2> 0 1PVD B 1PVDB KGYKP-VAVPA - 1 1PVD

  1. Data of evolutionary structure change: 1PVDA-2NXWA [Confc[Archive

    Lifescience Database Archive (English)

    Full Text Available 1PVDA-2NXWA 1PVD 2NXW A A SEITLGKYLFERLKQVNVNTVFGLPGDFNLSLLDKIYEV...YSSTLGVAAVTYGAGAFNMVNAVAGAYAEKSPVVVISGAPGTTEGGL---LLDTQFQVFKEITVAQARLDDPAKAPAEIARVLGAARAQSRPVYLEIPRNMVNAEVE------PVGDDPAWPVD...ex>0 1PVD A 1PVDA THR CA 228 GLN CA 326 1PVD A 1PVDA SHHTLGNGDFTVF

  2. Photovoltaic device and method

    Science.gov (United States)

    Cleereman, Robert J; Lesniak, Michael J; Keenihan, James R; Langmaid, Joe A; Gaston, Ryan; Eurich, Gerald K; Boven, Michelle L

    2015-01-27

    The present invention is premised upon an improved photovoltaic device ("PVD") and method of use, more particularly to an improved photovoltaic device with an integral locator and electrical terminal mechanism for transferring current to or from the improved photovoltaic device and the use as a system.

  3. Watchdog System

    DEFF Research Database (Denmark)

    Madsen, Tanja Kidholm Osmann; Bahnsen, Chris Holmberg; Jensen, Morten Bornø

    This deliverable is part of WP4. Overall WP4 is motivated by the need for automatic systems that can ease the task of annotating massive amounts of traffic data. Concretely this deliverable is related to WP4.2 - the watchdog system. The idea with the watchdog is to develop a system that can remov...... huge chunks of video data where no events/interactions of interest are occurring and hence let a user focus on manually annotation of only the interesting stuff....

  4. Dynamical systems

    CERN Document Server

    Sternberg, Shlomo

    2010-01-01

    Celebrated mathematician Shlomo Sternberg, a pioneer in the field of dynamical systems, created this modern one-semester introduction to the subject for his classes at Harvard University. Its wide-ranging treatment covers one-dimensional dynamics, differential equations, random walks, iterated function systems, symbolic dynamics, and Markov chains. Supplementary materials offer a variety of online components, including PowerPoint lecture slides for professors and MATLAB exercises.""Even though there are many dynamical systems books on the market, this book is bound to become a classic. The the

  5. Water systems

    International Nuclear Information System (INIS)

    Riess, R.

    1980-01-01

    The present paper describes the coolant chemistry and its consequences for 1300 MWsub(e) KWU PWR plants. Some selected systems, i.e. primary heat transport system, steam water cycle and cooling water arrangements, are chosen for this description. Various aspects of coolant chemistry regarding general corrosion, selective types of corrosion and deposits on heat transfer surfaces have been discussed. The water supply systems necessary to fulfill the requirements of the coolant chemistry are discussed as well. It has been concluded that a good operating performance can only be achieved when - beside other factors - the water chemistry has been given sufficient consideration. (orig./RW)

  6. Water systems

    International Nuclear Information System (INIS)

    Riess, R.

    1981-01-01

    The present paper describes the coolant chemistry and its consequences for 1300 MWsub(e) KWU PWR plants. Some selected systems, i.e. primary heat transport system, steam water cycle and cooling water arrangements, are chosen for this description. Various aspects of coolant chemistry regarding general corrosion, selective types of corrosion and deposits on heat transfer surface have been discussed. The water supply systems necessary to fulfill the requirements of the coolant chemistry are discussed as well. It has been concluded that a good operating performance can only be achieved when - beside other factors - the water chemistry has been given sufficient consideration. (orig./RW)

  7. Imaging system

    International Nuclear Information System (INIS)

    Froggatt, R.J.

    1981-01-01

    The invention provides a two dimensional imaging system in which a pattern of radiation falling on the system is detected to give electrical signals for each of a plurality of strips across the pattern. The detection is repeated for different orientations of the strips and the whole processed by compensated back projection. For a shadow x-ray system a plurality of strip x-ray detectors are rotated on a turntable. For lower frequencies the pattern may be rotated with a Dove prism and the strips condensed to suit smaller detectors with a cylindrical lens. (author)

  8. Kaonic systems

    Directory of Open Access Journals (Sweden)

    Oset E.

    2012-12-01

    Full Text Available I make a short review of the situation of the kaonic systems, with novel information supporting the two Λ(1405 states from the K-d → nπΣ reaction. A review is made of the K¯$ar K$NN system with recent calculations converging to smaller bindings and larger widths. Novel systems involving two kaons and one nucleon or three kaons are also reported and finally a short discussion is made of the analogous state DNN for which recent studies find a large binding and a small width.

  9. The systems integration modeling system

    International Nuclear Information System (INIS)

    Danker, W.J.; Williams, J.R.

    1990-01-01

    This paper discusses the systems integration modeling system (SIMS), an analysis tool for the detailed evaluation of the structure and related performance of the Federal Waste Management System (FWMS) and its interface with waste generators. It's use for evaluations in support of system-level decisions as to FWMS configurations, the allocation, sizing, balancing and integration of functions among elements, and the establishment of system-preferred waste selection and sequencing methods and other operating strategies is presented. SIMS includes major analysis submodels which quantify the detailed characteristics of individual waste items, loaded casks and waste packages, simulate the detailed logistics of handling and processing discrete waste items and packages, and perform detailed cost evaluations

  10. ring system

    African Journals Online (AJOL)

    1,3,2-DIAZABORACYCLOALKANE. RING SYSTEM. Negussie Retta" and Robert H. Neilson. 'Department of Chemistry, Addis Ababa University, P.O. Box 1176, Addis Ababa, Ethiopia. Department of Chemistry, Texas Christian University.

  11. Septic Systems

    Science.gov (United States)

    The web site provides guidance and technical assistance for homeowners, government officials, industry professionals, and EPA partners about how to properly develop and manage individual onsite and community cluster systems that treat domestic wastewater.

  12. Respiratory system

    Science.gov (United States)

    Bartlett, R. G., Jr.

    1973-01-01

    The general anatomy and function of the human respiratory system is summarized. Breathing movements, control of breathing, lung volumes and capacities, mechanical relations, and factors relevant to respiratory support and equipment design are discussed.

  13. Bubble systems

    CERN Document Server

    Avdeev, Alexander A

    2016-01-01

    This monograph presents a systematic analysis of bubble system mathematics, using the mechanics of two-phase systems in non-equilibrium as the scope of analysis. The author introduces the thermodynamic foundations of bubble systems, ranging from the fundamental starting points to current research challenges. This book addresses a range of topics, including description methods of multi-phase systems, boundary and initial conditions as well as coupling requirements at the phase boundary. Moreover, it presents a detailed study of the basic problems of bubble dynamics in a liquid mass: growth (dynamically and thermally controlled), collapse, bubble pulsations, bubble rise and breakup. Special emphasis is placed on bubble dynamics in turbulent flows. The analysis results are used to write integral equations governing the rate of vapor generation (condensation) in non-equilibrium flows, thus creating a basis for solving a number of practical problems. This book is the first to present a comprehensive theory of boil...

  14. Systems Biology

    Indian Academy of Sciences (India)

    IAS Admin

    study and understand the function of biological systems, particu- larly, the response of such .... understand the organisation and behaviour of prokaryotic sys- tems. ... relationship of the structure of a target molecule to its ability to bind a certain ...

  15. Bricks / Systems

    DEFF Research Database (Denmark)

    At first glance, this book may appear eclectic. It contains writings from architectural practice in a language and structure based on subjective views and experiences, combined with research contributions based on systematic design investigations of discrete computational systems. Discussions range......, and it aims to illustrate and identify new modes of working in architecture, particularly with regards to brickwork and other complex systems of modular assemblies, whether physical or digital....

  16. Expert Systems

    OpenAIRE

    Lucas, P.J.F.

    2005-01-01

    Expert systems mimic the problem-solving activity of human experts in specialized domains by capturing and representing expert knowledge. Expert systems include a knowledge base, an inference engine that derives conclusions from the knowledge, and a user interface. Knowledge may be stored as if-then rules, orusing other formalisms such as frames and predicate logic. Uncertain knowledge may be represented using certainty factors, Bayesian networks, Dempster-Shafer belief functions, or fuzzy se...

  17. Nanorobotic Systems

    Directory of Open Access Journals (Sweden)

    Lixin Dong

    2008-11-01

    Full Text Available Two strategies towards the realization of nanotechnology have been presented, i.e., top-down and bottom up. The former one is mainly based on nanofabrication and includes technologies such as nano-lithography, nano-imprint, and etching. Presently, they are still 2D fabrication processes with low resolution. The later one is an assembly-based technique. At present, it includes such items as self-assembly, dip-pen lithography, and directed self-assembly. These techniques can generate regular nano patterns in large scales. To fabricate 3D complex nano devices there are still no effective ways by so far. Here we show our effort on the development of a nano laboratory, a prototype nanomanufacturing system, based on nanorobotic manipulations. In which, we take a hybrid strategy as shown in Fig. 1. In this system, nano fabrication and nano assembly can be performed in an arbitrary order to construct nano building blocks and finally nano devices. The most important feature in this system is that the products can be fed back into the system to shrink the system part by part leading to nanorobots. Property characterization can be performed in each intermediate process. Due to the nanorobotic manipulation system, dynamic measurement can be performed rather than conventional static observations.

  18. Fiscal system analysis - contractual systems

    International Nuclear Information System (INIS)

    Kaiser, M.J.

    2006-01-01

    Production sharing contracts are one of the most popular forms of contractual system used in petroleum agreements around the world, but the manner in which the fiscal terms and contract parameters impact system measures is complicated and not well understood. The purpose of this paper is to quantify the influence of private and market uncertainty in contractual fiscal systems. A meta-modelling approach is employed that couples the results of a simulation model with regression analysis to construct numerical functionals that quantify the fiscal regime. Relationships are derived that specify how the present value, rate of return, and take statistics vary as a function of the system parameters. The deepwater Girassol field development in Angola is taken as a case study. (author)

  19. Reactor system

    International Nuclear Information System (INIS)

    Miyano, Hiroshi; Narabayashi, Naoshi.

    1990-01-01

    The represent invention concerns a reactor system with improved water injection means to a pressure vessel of a BWR type reactor. A steam pump is connected to a heat removing system pipeline, a high pressure water injection system pipeline and a low pressure water injection system pipeline for injecting water into the pressure vessel. A pump actuation pipeline is disposed being branched from a main steam pump or a steam relieaf pipeline system, through which steams are supplied to actuate the steam pump and supply cooling water into the pressure vessel thereby cooling the reactor core. The steam pump converts the heat energy into the kinetic energy and elevates the pressure of water to a level higher than the pressure of the steams supplied by way of a pressure-elevating diffuser. Cooling water can be supplied to the pressure vessel by the pressure elevation. This can surely inject cooling water into the pressure vessel upon loss of coolant accident or in a case if reactor scram is necessary, without using an additional power source. (I.N.)

  20. ARAC system

    International Nuclear Information System (INIS)

    Kelly, M.F.; Wyman, R.H.

    1975-01-01

    In spite of the remarkable safety record of the nuclear industry as a whole, recent public concern over the potential impact of the industry's accelerated growth has prompted ERDA to expand its emergency response procedures. The Atmospheric Release Advisory Capability, ARAC, is a computer communications system designed to enhance the existing emergency response capability of ERDA nuclear facilities. ARAC will add at least two new functions to this capability: centralized, real-time data acquisition and storage, and simulation of the long range atmospheric transport of hazardous materials. To perform these functions, ARAC employs four major sub-systems or facilities: the site facility, the central facility, the global weather center and the regional model. The system has been under development for the past two years at the Lawrence Livermore Laboratory of the University of California

  1. Microbiology System

    Science.gov (United States)

    1992-01-01

    Technology originating in a NASA-sponsored study of the measurement of microbial growth in zero gravity led to the development of Biomerieux Vitek, Inc.'s VITEK system. VITEK provides a physician with accurate diagnostic information and identifies the most effective medication. Test cards are employed to identify organisms and determine susceptibility to antibiotics. A photo-optical scanner scans the card and monitors changes in the growth of cells contained within the card. There are two configurations - VITEK and VITEK JR as well as VIDAS, a companion system that detects bacteria, viruses, etc. from patient specimens. The company was originally created by McDonnell Douglas, the NASA contractor.

  2. Spin systems

    CERN Document Server

    Caspers, W J

    1989-01-01

    This book is about spin systems as models for magnetic materials, especially antiferromagnetic lattices. Spin-systems are well-defined models, for which, in special cases, exact properties may be derived. These special cases are for the greater part, one- dimensional and restricted in their applicability, but they may give insight into general properties that also exist in higher dimension. This work pays special attention to qualitative differences between spin lattices of different dimensions. It also replaces the traditional picture of an (ordered) antiferromagnetic state of a Heisenberg sy

  3. Distributed systems

    CERN Document Server

    Van Steen, Maarten

    2017-01-01

    For this third edition of "Distributed Systems," the material has been thoroughly revised and extended, integrating principles and paradigms into nine chapters: 1. Introduction 2. Architectures 3. Processes 4. Communication 5. Naming 6. Coordination 7. Replication 8. Fault tolerance 9. Security A separation has been made between basic material and more specific subjects. The latter have been organized into boxed sections, which may be skipped on first reading. To assist in understanding the more algorithmic parts, example programs in Python have been included. The examples in the book leave out many details for readability, but the complete code is available through the book's Website, hosted at www.distributed-systems.net.

  4. Are there still roles for exocrine bladder drainage and portal venous drainage for pancreatic allografts?

    Science.gov (United States)

    Young, Carlton J

    2009-02-01

    Controversy remains regarding the best methodology of handling exocrine pancreatic fluid and pancreatic venous effluent. Bladder drainage has given way to enteric drainage. However, is there an instance in which bladder drainage is preferable? Also, hyperinsulinemia, as a result of systemic venous drainage (SVD), is claimed to be proatherosclerotic, whereas portal venous drainage (PVD) is more physiologic and less atherosclerotic. Bladder drainage remains a viable method of exocrine pancreas drainage, but evidence is sparse that measuring urinary amylase has a substantial benefit in the early detection of acute rejection in all types of pancreas transplants. Currently, there is no incontrovertible evidence that systemic hyperinsulinemia is proatherosclerotic, whereas recent metabolic studies on SVD and PVD showed that there was no benefit to PVD. Given the advent of newer immunosuppressive agents and overall lower acute rejection rates, the perceived benefit of bladder drainage as a means to measure urinary amylase as an early marker of rejection has not been substantiated. However, there may be a selective role for bladder drainage in 'high risk' pancreases. Also, without a clear-cut metabolic benefit to PVD over SVD, it remains the surgeon's choice as to which method to use.

  5. Immune System

    Science.gov (United States)

    ... of the Immune System Print en español El sistema inmunitario Whether you're stomping through the showers ... of Use Notice of Nondiscrimination Visit the Nemours Web site. Note: All information on TeensHealth® is for ...

  6. Operating Systems

    Indian Academy of Sciences (India)

    areas in which this type is useful are multimedia, virtual reality, and advanced scientific projects such as undersea exploration and planetary rovers. Because of the expanded uses for soft real-time functionality, it is finding its way into most current operating systems, including major versions of Unix and Windows NT OS.

  7. Barrier Systems

    NARCIS (Netherlands)

    Heteren, S. van

    2015-01-01

    Barrier-system dynamics are a function of antecedent topography and substrate lithology, Relative sea-level (RSL) changes, sediment availability and type, climate, vegetation type and cover, and various aero- and hydrodynamic processes during fair-weather conditions and extreme events. Global change

  8. Systems Science

    Science.gov (United States)

    Christakis, Alexander; Hammond, Debora; Jackson, Michael; Laszlo, Alexander; Mitroff, Ian; Snowden, Dave; Troncale, Len; Carr-Chellman, Alison; Spector, J. Michael; Wilson, Brent

    2013-01-01

    Scholars representing the field of systems science were asked to identify what they considered to be the most exciting and imaginative work currently being done in their field, as well as how that work might change our understanding. The scholars included Alexander Christakis, Debora Hammond, Michael Jackson, Alexander Laszlo, Ian Mitroff, Dave…

  9. Transport system

    NARCIS (Netherlands)

    Drenth, K.F.

    1999-01-01

    The transport system comprises at least one road surface (2) and at least one vehicle (4) on wheels (6). The road surface (2) has a substantially bowl-shaped cross section and the vehicle (4) is designed so that the wheels (6) run directly on the road surface (2) while the road surface (2) acts as a

  10. Quorum Systems

    DEFF Research Database (Denmark)

    Wattenhofer, Roger; Förster, Klaus-Tycho

    2016-01-01

    What happens if a single server is no longer powerful enough to service all your customers? The obvious choice is to add more servers and to use the majority approach (e.g. Paxos, Chapter 2) to guarantee consistency. However, even if you buy one million servers, a client still has to access more ...... study the theory behind overlapping sets, known as quorum systems....

  11. System Dynamics

    Science.gov (United States)

    Morecroft, John

    System dynamics is an approach for thinking about and simulating situations and organisations of all kinds and sizes by visualising how the elements fit together, interact and change over time. This chapter, written by John Morecroft, describes modern system dynamics which retains the fundamentals developed in the 1950s by Jay W. Forrester of the MIT Sloan School of Management. It looks at feedback loops and time delays that affect system behaviour in a non-linear way, and illustrates how dynamic behaviour depends upon feedback loop structures. It also recognises improvements as part of the ongoing process of managing a situation in order to achieve goals. Significantly it recognises the importance of context, and practitioner skills. Feedback systems thinking views problems and solutions as being intertwined. The main concepts and tools: feedback structure and behaviour, causal loop diagrams, dynamics, are practically illustrated in a wide variety of contexts from a hot water shower through to a symphony orchestra and the practical application of the approach is described through several real examples of its use for strategic planning and evaluation.

  12. System Description:

    DEFF Research Database (Denmark)

    Schürmann, Carsten; Poswolsky, Adam

    2009-01-01

    Delphin is a functional programming language [Adam Poswolsky and Carsten Schürmann. Practical programming with higher-order encodings and dependent types. In European Symposium on Programming (ESOP), 2008] utilizing dependent higher-order datatypes. Delphin's two-level type-system cleanly separates...

  13. Immune System

    Science.gov (United States)

    A properly functioning immune system is essential to good health. It defends the body against infectious agents and in some cases tumor cells. Individuals with immune deficiencies resulting from genetic defects, diseases (e.g., AIDS, leukemia), or drug therapies are more suscepti...

  14. Bioenergy systems

    International Nuclear Information System (INIS)

    Mitchell, C.P.

    1997-01-01

    The objective of this paper is to demonstrate that a bioenergy system has to be considered as an integrated process in which each stage or step interacts with other steps in the overall process. There are a number of stages in the supply and conversion of woody biomass for energy. Each step in the chain has implications for the next step and for overall system efficiency. The resource can take many forms and will have varying physical and chemical characteristics which will influence the efficiency and cost of conversion. The point in the supply chain at which size and moisture content is reduced and the manner in which it is done is influential in determining feedstock delivered cost and overall system costs. To illustrate the interactions within the overall system, the influence of the nature, size and moisture content of delivered feedstocks on costs of generating electricity via thermal conversion processes is examined using a model developed to investigate the inter-relationships between the stages in the supply chain. (author)

  15. Urogenital system

    International Nuclear Information System (INIS)

    Hamm, B.; Asbach, P.; Beyersdorff, D.; Hein, P.; Zaspel, U.

    2007-01-01

    The book is focussed on the radiological diagnostics of diseases in the urogential system. The description of the specific diseases, the identification by modern imaging techniques, the interpretation of examinatory results and therapeutic options are systematically treated in 4 chapters: kidney and adrenal glands, urinary tract, male genitals, female genitals

  16. Mirror systems.

    Science.gov (United States)

    Fogassi, Leonardo; Ferrari, Pier Francesco

    2011-01-01

    Mirror neurons are a class of visuomotor neurons, discovered in the monkey premotor cortex and in an anatomically connected area of the inferior parietal lobule, that activate both during action execution and action observation. They constitute a circuit dedicated to match actions made by others with the internal motor representations of the observer. It has been proposed that this matching system enables individuals to understand others' behavior and motor intentions. Here we will describe the main features of mirror neurons in monkeys. Then we will present evidence of the presence of a mirror system in humans and of its involvement in several social-cognitive functions, such as imitation, intention, and emotion understanding. This system may have several implications at a cognitive level and could be linked to specific social deficits in humans such as autism. Recent investigations addressed the issue of the plasticity of the mirror neuron system in both monkeys and humans, suggesting also their possible use in rehabilitation. WIREs Cogn Sci 2011 2 22-38 DOI: 10.1002/wcs.89 For further resources related to this article, please visit the WIREs website. Copyright © 2010 John Wiley & Sons, Ltd.

  17. Systemic Planning

    DEFF Research Database (Denmark)

    Leleur, Steen

    This book presents principles and methodology for planning in a complex world. It sets out a so-called systemic approach to planning, among other things, by applying “hard” and “soft” methodologies and methods in combination. The book is written for Ph.D and graduate students in engineering...

  18. Energy systems

    International Nuclear Information System (INIS)

    Haefele, W.

    1974-01-01

    Up to the present the production, transmission and distribution of energy has been considered mostly as a fragmented problem; at best only subsystems have been considered. Today the scale of energy utilization is increasing rapidly, and correspondingly, the reliance of societies on energy. Such strong quantitative increases influence the qualitative nature of energy utilization in most of its aspects. Resources, reserves, reliability and environment are among the key words that may characterize the change in the nature of the energy utilization problem. Energy can no longer be considered an isolated technical and economical problem, rather it is embedded in the ecosphere and the society-technology complex. Restraints and boundary conditions have to be taken into account with the same degree of attention as in traditional technical problems, for example a steam turbine. This results in a strong degree of interweaving. Further, the purpose of providing energy becomes more visible, that is, to make survival possible in a civilized and highly populated world on a finite globe. Because of such interweaving and finiteness it is felt that energy should be considered as a system and therefore the term 'energy systems' is used. The production of energy is only one component of such a system; the handling of energy and the embedding of energy into the global and social complex in terms of ecology, economy, risks and resources are of similar importance. he systems approach to the energy problem needs more explanation. This paper is meant to give an outline of the underlying problems and it is hoped that by so doing the wide range of sometimes confusing voices about energy can be better understood. Such confusion starts already with the term 'energy crisis'. Is there an energy crisis or not? Much future work is required to tackle the problems of energy systems. This paper can only marginally help in that respect. But it is hoped that it will help understand the scope of the

  19. Energy systems

    Energy Technology Data Exchange (ETDEWEB)

    Haefele, W [Nuclear Research Centre, Applied Systems Analysis and Reactor Physics, Karlsruhe (Germany); International Institute for Applied Systems Analysis, Laxenburg (Austria)

    1974-07-01

    Up to the present the production, transmission and distribution of energy has been considered mostly as a fragmented problem; at best only subsystems have been considered. Today the scale of energy utilization is increasing rapidly, and correspondingly, the reliance of societies on energy. Such strong quantitative increases influence the qualitative nature of energy utilization in most of its aspects. Resources, reserves, reliability and environment are among the key words that may characterize the change in the nature of the energy utilization problem. Energy can no longer be considered an isolated technical and economical problem, rather it is embedded in the ecosphere and the society-technology complex. Restraints and boundary conditions have to be taken into account with the same degree of attention as in traditional technical problems, for example a steam turbine. This results in a strong degree of interweaving. Further, the purpose of providing energy becomes more visible, that is, to make survival possible in a civilized and highly populated world on a finite globe. Because of such interweaving and finiteness it is felt that energy should be considered as a system and therefore the term 'energy systems' is used. The production of energy is only one component of such a system; the handling of energy and the embedding of energy into the global and social complex in terms of ecology, economy, risks and resources are of similar importance. he systems approach to the energy problem needs more explanation. This paper is meant to give an outline of the underlying problems and it is hoped that by so doing the wide range of sometimes confusing voices about energy can be better understood. Such confusion starts already with the term 'energy crisis'. Is there an energy crisis or not? Much future work is required to tackle the problems of energy systems. This paper can only marginally help in that respect. But it is hoped that it will help understand the scope of the

  20. Corrosion Characteristics of Nano-structured Coatings for the Application in Secondary Piping System of Nuclear Power Plants

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Jeong Won; Kim, Seung Hyun; Kim, Ji Hyun [Ulsan National Institute of Science and Technology, Ulsan (Korea, Republic of)

    2015-05-15

    Coating surface using less corrosive metal is one of methods that reduce electrochemical corrosion. And metal oxide like a TiO{sub 2} is studied because it is stable, insoluble when coating is exposed severe environment. Several coating technics are used for better corrosion resistance. Pysical vapor deposition(PVD), chemical vapor deposition(CVD), thermal spray, electroplating, electroless etc. But thermal spray coating makes thermal stress to substrates because its temperature are more than 3000K. And powder's deformation can occur. And CVD makes decarburization near interface between surface and coating layer. In addition, CVD and PVD needs vacuum chamber. Electroplating is chemical reaction at surface, but it needs electric power. On the other hands, electroless plating dosen't needs electric power and it's temperature is low than thermal spray. Also the pipe dipping into the chemically solution can proceed coating easily. To reduce FAC, we have experiment about corrosion resistance of electroless Ni-P coated carbon steel in room temperature. And it has possibility of reducing corrosion and addition of TiO{sub 2} nano particles in Ni-P coating layer makes having better corrosion resistance. And results give us a possibility that electroless Ni-P coating added TiO{sub 2} nano particle can have better corrosion resistance compared carbon steel. So it needs study about high temperature corrosion experiment of electroless Ni-P coating added TiO{sub 2} nano particle.

  1. TUBO system

    International Nuclear Information System (INIS)

    Barbosa, H.J.C.; Guerreiro, J.N.C.; Toledo, E.M.

    1980-01-01

    Proceedings recently incorporated to TUBO system like the seismic analysis and the stress verification acccording to ASME-Boiler Rule and Pressure Vessel Code-section III are presented. The seismic analysis comprehend the consideration of uniform motion of the support, its multiple excitation, and the attainment of the spectral response for both cases. The module for stress verification uses stresses resulting fromthe combination of the loads specified by the user, in the automatic verification of permissible stresses for the pipings class 1 and 2, based on criteria NB-3650 and NC-3650 of ASME. The implementation of these proceedings in the TUBO system are discussed and a numerical example that covers the different phases of a stress analysis in a piping is presented [pt

  2. Solar Systems

    Science.gov (United States)

    1979-01-01

    The solar collectors shown are elements of domestic solar hot water systems produced by Solar One Ltd., Virginia Beach, Virginia. Design of these systems benefited from technical expertise provided Solar One by NASA's Langley Research Center. The company obtained a NASA technical support package describing the d e sign and operation of solar heating equipment in NASA's Tech House, a demonstration project in which aerospace and commercial building technology are combined in an energy- efficient home. Solar One received further assistance through personal contact with Langley solar experts. The company reports that the technical information provided by NASA influenced Solar One's panel design, its selection of a long-life panel coating which increases solar collection efficiency, and the method adopted for protecting solar collectors from freezing conditions.

  3. Bilateral system. The ABACC system

    International Nuclear Information System (INIS)

    Nicolas, Ruben O.

    2001-01-01

    After relating the antecedents of the creation of the Brazilian-Argentine Agency for the Accounting and Control of Nuclear Materials (ABACC), the paper describes the common system of accounting and control set up by Argentina and Brazil. The organization of ABACC is also outlined

  4. Physical system requirements: Overall system

    International Nuclear Information System (INIS)

    1992-01-01

    The Nuclear Waste Policy Act (NWPA) of 1982 assigned to the Department of Energy (DOE) the responsibility for managing the disposal of spent nuclear fuel and high-level radioactive waste and established the Office of Civilian Radioactive Waste Management (OCRWM) for that purpose. The Secretary of Energy, in his November 1989 report to Congress (DOE/RW-0247), announced three new initiatives for conduct of the Civilian Radioactive Waste Management (CRWM) program. One of these initiatives was to establish improved management structure and procedures. In response, OCRWM performed a management study and the Direct subsequently issued the Management Systems Improvement Strategy (MSIS) on August 10, 1990, calling for a rigorous implementation of systems engineering principles with a special emphasis on functional analysis. This approach establishes a framework for integrating the program management efforts with the technical requirements analysis into a single, unified, and consistent program. The functional analysis approach recognizes that just the facilities and equipment comprising the physical waste management system must perform certain functions, so must certain programmatic and management functions be performed within the program in order to successfully bring the physical system into being

  5. Security system

    Science.gov (United States)

    Baumann, Mark J.; Kuca, Michal; Aragon, Mona L.

    2016-02-02

    A security system includes a structure having a structural surface. The structure is sized to contain an asset therein and configured to provide a forceful breaching delay. The structure has an opening formed therein to permit predetermined access to the asset contained within the structure. The structure includes intrusion detection features within or associated with the structure that are activated in response to at least a partial breach of the structure.

  6. Cardiovascular system

    International Nuclear Information System (INIS)

    Soulen, R.L.; Grosh, J.

    1984-01-01

    Invasive cardiovascular diagnostic procedures involve a finite risk and therefore can be recommended only when the benefit appears to exceed the risk by a substantial margin. The risk/benefit ratio varies not only with the procedure concerned but with the status of the vascular system, concomitant diseases, and the risks of both the suspected illness and its treatment. The risks inherent in the procedures per se are detailed in the sections to follow

  7. Priority Systems

    OpenAIRE

    Gössler , Gregor; Sifakis , Joseph

    2004-01-01

    Projet POP_ART; We present a framework for the incremental construction of deadlock-free systems meeting given safety properties. The framework borrows concepts and basic results from the controller synthesis paradigm by considering a step in the construction process as a controller synthesis problem. We show that priorities are expressive enough to represent restrictions induced by deadlock-free controllers preserving safety properties. We define a correspondence between such restrictions an...

  8. Imaging system

    International Nuclear Information System (INIS)

    Rushbrooke, J.G.; Ansorge, R.E.

    1987-01-01

    A moving object such as a container on a conveyor belt is imaged by an optical system onto a charge coupled device array in which the lines of the array are arranged perpendicular to the direction of motion of the object. The speed of movement of the object is sensed to generate electrical signals which are processed to provide shift signals enabling the shifting of data row to row in the array in synchronism with the movement of the container. The electrical charge associated with a given point on the array is transferred from one line to the other until it appears at the last line of the array, from which it is read out in known manner in conjunction with all other electrical charges associated with the row of charge coupled devices in the last line of the array. Due to the integrating effect achieved, the aperture of the imaging system can be much smaller than otherwise would be required, and/or the level of light illumination can be reduced. The imaging system can be applied to X-ray inspection devices, aerial surveillance or scanning of moving documents in copying processes. (author)

  9. Braking system

    Science.gov (United States)

    Norgren, D.U.

    1982-09-23

    A balanced braking system comprising a plurality of braking assemblies located about a member to be braked. Each of the braking assemblies consists of a spring biased piston of a first material fitted into a body of a different material which has a greater contraction upon cooling than the piston material. The piston is provided with a recessed head portion over which is positioned a diaphragm and forming a space therebetween to which is connected a pressurized fluid supply. The diaphragm is controlled by the fluid in the space to contact or withdraw from the member to be braked. A cooling means causes the body within which the piston is fitted to contract more than the piston, producing a tight shrink fit therebetween. The braking system is particularly applicable for selectively braking an arbor of an electron microscope which immobilizes, for example, a vertically adjustable low temperature specimen holder during observation. The system provides balanced braking forces which can be easily removed and re-established with minimal disturbance to arbor location.

  10. Protecting information in systems of systems

    NARCIS (Netherlands)

    Trivellato, D.

    2012-01-01

    Systems of systems are coalitions of autonomous and heterogeneous systems that collaborate to achieve a common goal. The component systems of a system of systems often belong to different security domains, which are governed by different authorities (hereafter called parties). Furthermore, systems

  11. Enzyme-mediated quenching of the Pseudomonas quinolone signal (PQS promotes biofilm formation of Pseudomonas aeruginosa by increasing iron availability

    Directory of Open Access Journals (Sweden)

    Beatrix Tettmann

    2016-12-01

    Full Text Available The 2-alkyl-3-hydroxy-4(1H-quinolone 2,4-dioxygenase HodC was previously described to cleave the Pseudomonas quinolone signal, PQS, which is exclusively used in the complex quorum sensing (QS system of Pseudomonas aeruginosa, an opportunistic pathogen employing QS to regulate virulence and biofilm development. Degradation of PQS by exogenous addition of HodC to planktonic cells of P. aeruginosa attenuated production of virulence factors, and reduced virulence in planta. However, proteolytic cleavage reduced the efficacy of HodC. Here, we identified the secreted protease LasB of P. aeruginosa to be responsible for HodC degradation. In static biofilms of the P. aeruginosa PA14 lasB::Tn mutant, the catalytic activity of HodC led to an increase in viable biomass in newly formed but also in established biofilms, and reduced the expression of genes involved in iron metabolism and siderophore production, such as pvdS, pvdL, pvdA and pvdQ. This is likely due to an increase in the levels of bioavailable iron by degradation of PQS, which is able to sequester iron from the surrounding environment. Thus, HodC, despite its ability to quench the production of virulence factors, is contraindicated for combating P. aeruginosa biofilms.

  12. Study of Stress Migration Failure in SiLKTM/SiO2 Hybrid Cu Interconnects

    International Nuclear Information System (INIS)

    Tsuchikawa, Haruo; Nakamura, Tomoji; Suzuki, Takashi; Mori, Hiroko; Shono, Ken

    2004-01-01

    Stress migration (SM) behavior is studied for a 130nm-node SiLK TM /SiO2 hybrid structure in which the interlevel dielectrics (ILD) consist of SiLK TM for trench levels and SiO2 for via levels. The failure rate dependence on the temperature, line width and circuit is examined in detail. Furthermore, an effect of dielectric deposition process on the reliability of the hybrid interconnects is investigated. It has been found that SM behavior is essentially similar to that reported in Cu/SiO2 systems. It has also been clarified that SiO2 PVD conditions at via level had a large impact on the failure rate. Therefore, the control of ILD deposition conditions is found to be one of the key factors in suppressing the SM failure. In order to examine the effect of the PVD conditions, the residual stress in vias were measured by using X-ray diffraction method. The results show that σx (the stress component parallel to the surface) in vias greatly depends on the PVD conditions. Then, the relationship between the PVD conditions and the SM failure rate is clarified

  13. Dynamical systems

    CERN Document Server

    Birkhoff, George D

    1927-01-01

    His research in dynamics constitutes the middle period of Birkhoff's scientific career, that of maturity and greatest power. -Yearbook of the American Philosophical Society The author's great book€¦is well known to all, and the diverse active modern developments in mathematics which have been inspired by this volume bear the most eloquent testimony to its quality and influence. -Zentralblatt MATH In 1927, G. D. Birkhoff wrote a remarkable treatise on the theory of dynamical systems that would inspire many later mathematicians to do great work. To a large extent, Birkhoff was writing about his o

  14. Nuclear systems

    CERN Document Server

    Todreas, Neil E

    2011-01-01

    Principal Characteristics of Power ReactorsIntroductionPower CyclesPrimary Coolant SystemsReactor CoresFuel AssembliesAdvanced Water- and Gas-Cooled Reactors (Generation III And III+)Advanced Thermal and Fast Neutron Spectrum Reactors (Generation IV)ReferencesProblemsThermal Design Principles and ApplicationIntroductionOverall Plant Characteristics Influenced by Thermal Hydraulic ConsiderationsEnergy Production and Transfer ParametersThermal Design LimitsThermal Design MarginFigures of Merit for Core Thermal PerformanceThe Inverted Fuel ArrayThe Equivalent Annulus ApproximationReferencesProble

  15. Videobasierte Systeme

    Science.gov (United States)

    Knoll, Peter

    Videosensoren spielen für Fahrerassistenz systeme eine zentrale Rolle, da sie die Interpretation visueller Informationen (Objektklassifikation) gezielt unterstützen. Im Heckbereich kann die Video sensorik in der einfachsten Variante die ultraschallbasierte Einparkhilfe bei Einpark- und Rangiervorgängen unterstützen. Beim Nachtsichtsystem NightVision wird das mit Infrarotlicht angestrahlte Umfeld vor dem Fahrzeug mit einer Frontkamera aufgenommen und im Fahrzeugcockpit auf einem Display dem Fahrer angezeigt (s. Nachtsichtsysteme). Andere Fahrerassistenzsysteme verarbeiten die Videosignale und generieren daraus gezielt Informationen, die für eigenständige Funktionen (z. B. Spurverlassenswarner) oder aber als Zusatzinformation für andere Funktionen ausgewertet werden (Sensordatenfusion).

  16. Relaxation System

    Science.gov (United States)

    1987-01-01

    Environ Corporation's relaxation system is built around a body lounge, a kind of super easy chair that incorporates sensory devices. Computer controlled enclosure provides filtered ionized air to create a feeling of invigoration, enhanced by mood changing aromas. Occupant is also surrounded by multidimensional audio and the lighting is programmed to change colors, patterns, and intensity periodically. These and other sensory stimulators are designed to provide an environment in which the learning process is stimulated, because research has proven that while an individual is in a deep state of relaxation, the mind is more receptive to new information.

  17. Bearing system

    Science.gov (United States)

    Kapich, Davorin D.

    1987-01-01

    A bearing system includes backup bearings for supporting a rotating shaft upon failure of primary bearings. In the preferred embodiment, the backup bearings are rolling element bearings having their rolling elements disposed out of contact with their associated respective inner races during normal functioning of the primary bearings. Displacement detection sensors are provided for detecting displacement of the shaft upon failure of the primary bearings. Upon detection of the failure of the primary bearings, the rolling elements and inner races of the backup bearings are brought into mutual contact by axial displacement of the shaft.

  18. Propulsion Systems

    Science.gov (United States)

    2011-03-31

    stand.    CV CS x dAvvdVov dt d F   (18-1) Where  denotes density and vx is the velocity in the x-direction. The first term on the...by  but to avoid confusion with  from Eqs. 18-7 to 10, it is denoted k in this formula . Ru is the universal gas constant (8.314472 J/mol K), pe is...Russian Federation Used on Phobos spacecraft as main engines 74 1.03 NTO/ UDMH 13.73-19.61 316-325 Orbital Maneuvering System 1 Aerojet Shuttle

  19. Expert Systems: What Is an Expert System?

    Science.gov (United States)

    Duval, Beverly K.; Main, Linda

    1994-01-01

    Describes expert systems and discusses their use in libraries. Highlights include parts of an expert system; expert system shells; an example of how to build an expert system; a bibliography of 34 sources of information on expert systems in libraries; and a list of 10 expert system shells used in libraries. (Contains five references.) (LRW)

  20. System analysis and design

    International Nuclear Information System (INIS)

    Son, Seung Hui

    2004-02-01

    This book deals with information technology and business process, information system architecture, methods of system development, plan on system development like problem analysis and feasibility analysis, cases for system development, comprehension of analysis of users demands, analysis of users demands using traditional analysis, users demands analysis using integrated information system architecture, system design using integrated information system architecture, system implementation, and system maintenance.

  1. Posting system

    International Nuclear Information System (INIS)

    Hackney, S.

    1983-01-01

    A system for posting hazardous materials into and out of an enclosure, such as a glovebox, through a port in a wall of the enclosure. The port is normally closed by a door which cooperates with a removable end closure, on a container or the like when the latter is presented to and secured at the port. The container is secured in position at the port by means of a rotatable coupling ring. A single interlock ensures that the door cannot be opened in the absence of a container at the port and also that the container cannot be removed from the port when the door is open. In place of the container, a glove secured to a rigid sleeve may be used to enable the operator to perform a work function within the glovebox. (author)

  2. hydrothermal systems

    Directory of Open Access Journals (Sweden)

    L. Bayón

    2002-01-01

    Full Text Available In this paper, we revise the classical formulation of the problem depriving it of the concepts that are superfluous from the mathematical point of view. We observe that a number of power stations can be substituted by a single one that behaves equivalently to the entire set. Proceeding in this way, we obtain a variational formulation in its purest sense (without restrictions. This formulation allows us to employ the theory of calculus of variations to the highest degree. We then calculate the equivalent minimizer in the case where the cost functions are second-order polynomials. We prove that the equivalent minimizer is a second-order polynomial with piece-wise constant coefficients. Moreover, it belongs to the class C1. Finally, we present various examples prompted by real systems and perform the proposed algorithms using Mathematica.

  3. Nonlinear systems

    CERN Document Server

    Palmero, Faustino; Lemos, M; Sánchez-Rey, Bernardo; Casado-Pascual, Jesús

    2018-01-01

    This book presents an overview of the most recent advances in nonlinear science. It provides a unified view of nonlinear properties in many different systems and highlights many  new developments. While volume 1 concentrates on mathematical theory and computational techniques and challenges, which are essential for the study of nonlinear science, this second volume deals with nonlinear excitations in several fields. These excitations can be localized and transport energy and matter in the form of breathers, solitons, kinks or quodons with very different characteristics, which are discussed in the book. They can also transport electric charge, in which case they are known as polarobreathers or solectrons. Nonlinear excitations can influence function and structure in biology, as for example, protein folding. In crystals and other condensed matter, they can modify transport properties, reaction kinetics and interact with defects. There are also engineering applications in electric lattices, Josephson junction a...

  4. Posting system

    International Nuclear Information System (INIS)

    Jones, E.L.

    1983-01-01

    A posting system for the movement of equipment, such as a manipulator, into and out of an enclosure e.g. a cell or glovebox, for toxic or radioactive materials has the manipulator arranged within a collapsible bellows-like container with an end of the container cooperating with a port entry to the enclosure. The collapsible container isolates the manipulator from the environment outside the enclosure and allows the manipulator to enter and leave the contaminated enclosure without breach of the containment. A particular construction of cell for use with radioactive material is described, having a thick wall of shielding material such as concrete provided with a door normally closed by a Pb shutter and having a cylindrical gamma shield block located over the shutter on the exterior of the wall. (author)

  5. The predisposing pathology and clinical characteristics in the Scottish retinal detachment study.

    Science.gov (United States)

    Mitry, Danny; Singh, Jaswinder; Yorston, David; Siddiqui, M A Rehman; Wright, Alan; Fleck, Brian W; Campbell, Harry; Charteris, David G

    2011-07-01

    To describe the predisposing pathology and clinical features of all incident cases of rhegmatogenous retinal detachment (RRD) recruited in Scotland during a 2-year period. Prospective surveillance study of incident cases of RRD. All incident cases of RRD recruited as part of the Scottish Retinal Detachment Study. During a 2-year period, we coordinated a comprehensive system in which every case of primary RRD presenting to 1 of 6 vitreoretinal surgical sites in Scotland was examined and approached for study inclusion. Rhegmatogenous retinal detachment incidence, predisposing features, and clinical characteristics. A total of 1202 cases were recruited. Detailed clinical information was available on 1130 (94%) of cases. By causative break, the proportions of RRD were horseshoe tear (HST) associated with posterior vitreous detachment (PVD) in 86.2%, giant retinal tear (GRT) and PVD in 1.3%, non-PVD round hole (RH) in 4.9%, retinal dialysis in 5.9%, and retinoschisis RRD in 1.6%. One in 10 cases reported significant ocular trauma. One in 5 cases were pseudophakic. Round hole RRD more frequently presented with multiple retinal breaks compared with HST RRD (67.8% vs. 48.7%; P = 0.003). In PVD-associated RRD, 56.1% (95% confidence interval [CI], 53.8-58.3) of breaks were identified in the superotemporal retina. In non-PVD RRD, 54.6% (95% CI, 47.9-61.1) of breaks were inferotemporal, followed by superotemporal in 34.9% (95% CI, 28.7-41.5). Lattice degeneration was present in 18.7% of affected eyes and more common in RH RRD (35.7%) than in HST RRD (19.3%) (P = 0.003). Seven percent reported an affected first-degree relative, and these cases were significantly more myopic than nonfamilial cases. More than 85% of RRD cases are associated with PVD and related tractional tears. Non-PVD RH RRD occurred in younger and more myopic individuals. The majority of cases are caused by more than 1 retinal break, and the macula is affected in more than 50% at presentation. Ocular trauma

  6. Systems engineering simplified

    CERN Document Server

    Cloutier, Robert; Bone, Mary Alice

    2015-01-01

    IntroductionOverviewDiscussion of Common TerminologyThe Case for Systems EngineeringA Brief History of Systems EngineeringSystem ExamplesSummaryThe System Life CycleManaging System Development-The Vee ModelSystem ProductionSystem Utilization and SupportSystem Retirement and DisposalOther Systems Engineering Development ModelsSpiral ModelAgile Model for Systems EngineeringSystem of InterestAbstraction and DecompositionIntegrationDeveloping and Managing RequirementsCyclone Requiremen

  7. Effect of Suspension Plasma-Sprayed YSZ Columnar Microstructure and Bond Coat Surface Preparation on Thermal Barrier Coating Properties

    Science.gov (United States)

    Bernard, Benjamin; Quet, Aurélie; Bianchi, Luc; Schick, Vincent; Joulia, Aurélien; Malié, André; Rémy, Benjamin

    2017-08-01

    Suspension plasma spraying (SPS) is identified as promising for the enhancement of thermal barrier coating (TBC) systems used in gas turbines. Particularly, the emerging columnar microstructure enabled by the SPS process is likely to bring about an interesting TBC lifetime. At the same time, the SPS process opens the way to a decrease in thermal conductivity, one of the main issues for the next generation of gas turbines, compared to the state-of-the-art deposition technique, so-called electron beam physical vapor deposition (EB-PVD). In this paper, yttria-stabilized zirconia (YSZ) coatings presenting columnar structures, performed using both SPS and EB-PVD processes, were studied. Depending on the columnar microstructure readily adaptable in the SPS process, low thermal conductivities can be obtained. At 1100 °C, a decrease from 1.3 W m-1 K-1 for EB-PVD YSZ coatings to about 0.7 W m-1 K-1 for SPS coatings was shown. The higher content of porosity in the case of SPS coatings increases the thermal resistance through the thickness and decreases thermal conductivity. The lifetime of SPS YSZ coatings was studied by isothermal cyclic tests, showing equivalent or even higher performances compared to EB-PVD ones. Tests were performed using classical bond coats used for EB-PVD TBC coatings. Thermal cyclic fatigue performance of the best SPS coating reached 1000 cycles to failure on AM1 substrates with a β-(Ni,Pt)Al bond coat. Tests were also performed on AM1 substrates with a Pt-diffused γ-Ni/γ'-Ni3Al bond coat for which more than 2000 cycles to failure were observed for columnar SPS YSZ coatings. The high thermal compliance offered by both the columnar structure and the porosity allowed the reaching of a high lifetime, promising for a TBC application.

  8. Synthesis of nanocrystalline Cu1-xTax composites using physical vapor deposition

    International Nuclear Information System (INIS)

    Savage, H.S.; Wang, H.; Rigsbee, J.M.

    1993-01-01

    Physical vapor deposition (PVD) processes provide the capability for creating new types of metallic, ceramic, and polymeric composites by allowing atomic-scale engineering of structure and chemistry. Because PVD processes provide the capacity for circumventing thermodynamic factors, such as solubility limits, it is possible to produce nonequilibrium alloys and materials with unique mixtures of phases. The ease by which PVD produces materials with nanocrystalline microstructures is an added benefit of these processes. This paper describes ion plating, a plasma-assisted PVD process, and its application for the development of a new class of nanoscale dispersion-strengthened Cu 1-x Ta x alloys. Copper-tantalum was selected as a model system because the extensive liquid miscibility gap and nearly zero mutual solid solubilities prevent creation of Cu-Ta alloys by conventional or rapid solidification processes. Microchemical analyses of the family of Cu 1-x Ta x alloys indicate that PVD can produce materials with any desired level of Ta. X-ray diffraction and transmission electron microscopy analyses show that the as-deposited microstructures consist generally of a Cu matrix supersaturated with Ta and containing a uniform dispersion of Ta particles with diameters below 10 nm. The Ta particles are face centered cubic (exceptionally large Ta particles, larger than ∼100 nm, are body centered cubic) and are oriented identically with the Cu matrix. Particle coarsening studies, at temperatures up to 900C and for times as long as 100 hours, indicate an extreme degree of microstructural stability. The Ta particles also appear highly effective at maintaining a submicron Cu matrix grain size even after annealing at 900C

  9. Hard coatings

    International Nuclear Information System (INIS)

    Dan, J.P.; Boving, H.J.; Hintermann, H.E.

    1993-01-01

    Hard, wear resistant and low friction coatings are presently produced on a world-wide basis, by different processes such as electrochemical or electroless methods, spray technologies, thermochemical, CVD and PVD. Some of the most advanced processes, especially those dedicated to thin film depositions, basically belong to CVD or PVD technologies, and will be looked at in more detail. The hard coatings mainly consist of oxides, nitrides, carbides, borides or carbon. Over the years, many processes have been developed which are variations and/or combinations of the basic CVD and PVD methods. The main difference between these two families of deposition techniques is that the CVD is an elevated temperature process (≥ 700 C), while the PVD on the contrary, is rather a low temperature process (≤ 500 C); this of course influences the choice of substrates and properties of the coating/substrate systems. Fundamental aspects of the vapor phase deposition techniques and some of their influences on coating properties will be discussed, as well as the very important interactions between deposit and substrate: diffusions, internal stress, etc. Advantages and limitations of CVD and PVD respectively will briefly be reviewed and examples of applications of the layers will be given. Parallel to the development and permanent updating of surface modification technologies, an effort was made to create novel characterisation methods. A close look will be given to the coating adherence control by means of the scratch test, at the coating hardness measurement by means of nanoindentation, at the coating wear resistance by means of a pin-on-disc tribometer, and at the surface quality evaluation by Atomic Force Microscopy (AFM). Finally, main important trends will be highlighted. (orig.)

  10. Perceptual visual dysfunction, physical impairment and quality of life in Bangladeshi children with cerebral palsy.

    Science.gov (United States)

    Mitry, D; Williams, C; Northstone, K; Akter, A; Jewel, J; Khan, N; Muhit, M; Gilbert, C E; Bowman, R

    2016-09-01

    Cerebral palsy (CP) is the most common cause of motor disability in children and is often accompanied by sensory and/or cognitive impairment. The aim of this study was to characterise visual acuity impairment, perceptual visual dysfunction (PVD) and physical disability in a community-based sample of Bangladeshi children with CP and to assess the impact of these factors on the quality of life of the children. A key informant study was used to recruit children with CP from Sirajganj district. Gross Motor Function Classification System (GMFCS) levels and visual impairment were assessed by a physiotherapist and an optometrist, respectively. Assessments of visual perception were performed and standardised questionnaires were administered to each child's main carer to elicit indicators of PVD and parent-reported health-related quality of life. A generalised linear regression analysis was conducted to assess the determinants of the quality of life scores. 180 children were recruited. The median age was 8 years (IQR: 6-11 years); 112 (62%) were male; 57 (32%) had visual acuity impairment and 95 (53%) had some parent-reported PVD. In analyses adjusted for age, sex, GMFCS and acuity impairment, visual attention (pvisual search (p=0.020). PVD is an important contributor in reducing quality of life in children with CP, independent of motor disability and acuity impairment. Better characterisation of PVD is important to help design interventions for affected children, which may improve their quality of life. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/

  11. NJOY system

    International Nuclear Information System (INIS)

    Gil, Choong Sup; Kim, Jung Do

    1998-01-01

    The NJOY Nuclear Data Processing System is used to convert evaluated nuclear data in ENDF format into forms useful for applications. The NJOY code is a modular computer code designed to read evaluated data in ENDF format, transform the data in various ways, and output the results as libraries designed to be used in various applications. The modules are essentially independent programs, and they communicate with each other using input and output files, plus a very few common variables. The NJOY code can work with neutrons, photons, and charged particles. The evaluated nuclear data are reconstructed to pointwise cross sections from ENDF resonance parameters and interpolation schemes. The pointwise data can be Doppler broadened to the temperatures requested by users. The data in unresolved energy range can be computed to effective self-shielded pointwise cross sections. The cross sections and scattering matrices for free or bound scatterers in the thermal energy range are able to be produced. The self-shielded multigroup cross sections, group-to-group scattering matrices, photon-production matrices, and charged-particle cross sections from pointwise data can be generated for various application codes

  12. Chem systems

    International Nuclear Information System (INIS)

    Anon.

    1992-01-01

    This paper reports that world styrene demand, paced by a near doubling of combined requirements in East Asia and Oceania, could reach 19.3 million metric tons by 2000, an average growth rate of 3.7%/year. So concludes Chem Systems Inc., Tarrytown, N.Y., in a study of world styrene markets through the end of the century. Pacific Rim styrene production and consumption throughout the 1990s are predicted to make up increasingly larger shares of world markets, while demand and production lag in the U.S. and western Europe. Demand and capacity in other parts of the world will grow in real terms, increasing combined market shares only slightly. Most of the increase will be driven by demand in East Asia and Oceania, where consumption by century's end is expected to increase 4.48 million metric tons from 2.25 million tons in 1991. Meantime, Japan's styrene demand in 2000 is projected at 2.64 million tons, a 500,000 ton increase from 1991 demand but a net market loss of 1.9%

  13. Microfluidic system for monitoring of cardiac (H9C2) cell proliferation

    Science.gov (United States)

    Kobuszewska, A.; Cwik, P.; Jastrzebska, E.; Brzozka, Z.; Chudy, M.; Renaud, P.; Dybko, A.

    2017-05-01

    The paper presents the application of electrical impedance spectroscopy (EIS) analysis for investigation of cardiac cell (H9C2 - rat cardiomyoblast) proliferation after verapamil hydrochloride exposure. For this purpose, two different PDMS/glass microsystems with circular microchamber and longitudinal microchannel integrated with Pt/Al electrodes were used. The microchambers were fabricated in PDMS using photolithography and replica moulding techniques. Pt/Al electrodes were fabricated on a 4-inch glass substrate using Physical Vapor Deposition (PVD). Solution of verapamil hydrochloride was continuously introduced into the microsystems with H9C2 cell culture (a flow rate of 1 μl/min) for 72 h. The impedance spectra were recorded from 100 Hz to 1 MHz. We confirmed that impedance spectroscopy can be used for non-invasive, label-free and real-time analysis of cardiac cells proliferation based on cells dielectric properties and biological structure.

  14. Improvement of the low-speed friction characteristics of a hydraulic piston pump by PVD-coating of TiN

    International Nuclear Information System (INIS)

    Hong, Yeh Sun; Lee, Sang Yul; Kim, Sung Hun; Lim, Hyun Sik

    2006-01-01

    The hydraulic pump of an Electro-hydrostatic Actuator should be able to quickly feed large volume of oil into hydraulic cylinder in order to reduce the response time. On the other hand, it should be also able to precisely dispense small amount of oil through low-speed operation so that the steady state position control error of the actuator can be accurately compensated. Within the scope of axial piston type hydraulic pumps, this paper is focused on the investigation how the surface treatment of their cylinder barrel with TiN plasma coating can contribute to the reduction of the friction and wear rate of valve plate in the low-speed range with mixed lubrication. The results showed that the friction torque of the valve plate mated with a TiN-coated cylinder barrel could be reduced to 22% of that with an uncoated original one when load pressure was 300 bar and rotational speed 100 rpm. It means that the torque efficiency of the test pump was expected to increase more than 1.3% under the same working condition. At the same time, the wear rate of the valve plate could be reduced to 40∼50%

  15. Effect of Metal Ion Etching on the Tribological, Mechanical and Microstructural Properties of TiN-COATED d2 Tool Steel Using Cae Pvd Technique

    Science.gov (United States)

    Ali, Mubarak; Hamzah, Esah Binti; Hj. Mohd Toff, Mohd Radzi

    A study has been made on TiN coatings deposited on D2 tool steel substrates by using commercially available cathodic arc evaporation, physical vapor deposition technique. The goal of this work is to determine the usefulness of TiN coatings in order to improve the micro-Vickers hardness, coefficient of friction and surface roughness of TiN coating deposited on tool steel, which is vastly use in tool industry for various applications. A pin-on-disc test was carried out to study the coefficient of friction versus sliding distance of TiN coating at various ion etching rates. The tribo-test showed that the minimum value recorded for friction coefficient was 0.386 and 0.472 with standard deviation of 0.056 and 0.036 for the coatings deposited at zero and 16 min ion etching. The differences in friction coefficient and surface roughness was mainly associated with the macrodroplets, which was produced during etching stage. The coating deposited for 16 min metal ion etching showed the maximum hardness, i.e., about five times higher than uncoated one and 1.24 times to the coating deposited at zero ion etching. After friction test, the wear track was observed by using field emission scanning electron microscope. The coating deposited for zero ion etching showed small amounts of macrodroplets as compared to the coating deposited for 16 min ion etching. The elemental composition on the wear scar were investigated by means of energy dispersive X-ray, indicate no further TiN coating on wear track. A considerable improvement in TiN coatings was recorded as a function of various ion etching rates.

  16. Effect of Coating Thickness on the Properties of TiN Coatings Deposited on Tool Steels Using Cathodic Arc Pvd Technique

    Science.gov (United States)

    Mubarak, A.; Akhter, Parvez; Hamzah, Esah; Mohd Toff, Mohd Radzi Hj.; Qazi, Ishtiaq A.

    Titanium nitride (TiN) widely used as hard coating material, was coated on tool steels, namely on high-speed steel (HSS) and D2 tool steel by physical vapor deposition method. The study concentrated on cathodic arc physical vapor deposition (CAPVD), a technique used for the deposition of hard coatings for tooling applications, and which has many advantages. The main drawback of this technique, however, is the formation of macrodroplets (MDs) during deposition, resulting in films with rougher morphology. Various standard characterization techniques and equipment, such as electron microscopy, atomic force microscopy, hardness testing machine, scratch tester, and pin-on-disc machine, were used to analyze and quantify the following properties and parameters: surface morphology, thickness, hardness, adhesion, and coefficient of friction (COF) of the deposited coatings. Surface morphology revealed that the MDs produced during the etching stage, protruded through the TiN film, resulting in film with deteriorated surface features. Both coating thickness and indentation loads influenced the hardness of the deposited coatings. The coatings deposited on HSS exhibit better adhesion compared to those on D2 tool steel. Standard deviation indicates that the coating deposited with thickness around 6.7 μm showed the most stable trend of COF versus sliding distance.

  17. Microstructure and functional properties of the TiNi- and CuAl-based SMA thin films and coats produced by PVD technique

    International Nuclear Information System (INIS)

    Kolomytsev, V.; Musienko, R.; Nevdacha, V.; Panarin, V.; Pasko, A.; Cesari, E.; Segui, C.; Humbeeck, J. van

    2000-01-01

    The TiNi- and CuAl-based shape memory alloy thin films and wear/corrosion resistant surface coats have been produced by the ion-plasma deposition method with an arc dispersion of the cathode/target. This technique was widely used for production of the coats from a sprayed pure metal or a single-phase alloy. We have offered to use this process for dispersion of the heterophase alloys like shape memory alloys. The arguments for choosing of this technique are discussed with respect to creation of the conditions for preservation not only chemical composition, but also phase structure of an alloy in a covering, thus the shape memory/superelastic effects to be kept in a coat. (orig.)

  18. The quorum-quenching N-acyl homoserine lactone acylase PvdQ is an Ntn-hydrolase with an unusual substrate-binding pocket

    NARCIS (Netherlands)

    Bokhove, Marcel; Jimenez, Pol Nadal; Quax, Wim J.; Dijkstra, Bauke W.

    2010-01-01

    In many Gram-negative pathogens, their virulent behavior is regulated by quorum sensing, in which diffusible signals such as N-acyl homoserine lactones (AHLs) act as chemical messaging compounds. Enzymatic degradation of these diffusible signals by, e. g., lactonases or amidohydrolases abolishes AHL

  19. The cutting properties and wear of the knives with DLC and W-DLC coatings, deposited by PVD methods, applied for wood and wood-based materials machining

    OpenAIRE

    M. Pancielejko; A. Czyżniewski; A. Gilewicz; V. Zavaleyev; W. Szymański

    2012-01-01

    Purpose: Performance of DLC and W-DLC coated woodworking knives was investigated. The results of testing DLC and W-DLC coating properties as well as the results of life-time tests in the form of wear of HSS and HM knives with these coatings is presents.Design/methodology/approach: DLC coating was deposited by MCVA method, and W-DLC coating was deposited by pulsed RMS. Tests of knives coated with DLC and W-DLC as uncoated ones was made by machining: MDF board, pinewood slats and floorboard - u...

  20. Process-Structure-Property Relationships of Micron Thick Gadolinium Oxide Films Deposited by Reactive Electron Beam-Physical Vapor Deposition (EB-PVD)

    Science.gov (United States)

    2014-12-01

    transparency is important (i.e., protective eyewear , windshields, building windows and architecture, road signs, etc).22 However, for development of a Gd2G...B. in Industrial Minerals and Rocks 769-792 (2006). 32. Atwood, D. A. The Rare Earth Elements : Fundamentals and Applications. 1-624 (Wiley, 2013

  1. The effect of Al intermediate layer on thermal resistance of EB-PVD yttria-stabilized zirconia coatings on titanium substrate

    Science.gov (United States)

    Panin, Alexey; Panin, Victor; Kazachenok, Marina; Shugurov, Artur; Sinyakova, Elena; Martynov, Sergey; Rusyaev, Andrey; Kasterov, Artur

    2017-12-01

    The yttria-stabilized zirconia coatings sprayed on titanium substrates by the electron beam physical vapor deposition were subjected to thermal annealing in air at 1000°C for 1, 30 and 60 min. The delamination and fracture of the coatings are studied by the scanning electron microscopy and X-ray diffraction. It is shown that a magnetron sputtered Al interlayer between the coating and the substrate considerably improves the thermal resistance of ceramic coatings.

  2. Tribological and Wear Performance of Carbide Tools with TiB2 PVD Coating under Varying Machining Conditions of TiAl6V4 Aerospace Alloy

    Directory of Open Access Journals (Sweden)

    Jose Mario Paiva

    2017-11-01

    Full Text Available Tribological phenomena and tool wear mechanisms during machining of hard-to-cut TiAl6V4 aerospace alloy have been investigated in detail. Since cutting tool wear is directly affected by tribological phenomena occurring between the surfaces of the workpiece and the cutting tool, the performance of the cutting tool is strongly associated with the conditions of the machining process. The present work shows the effect of different machining conditions on the tribological and wear performance of TiB2-coated cutting tools compared to uncoated carbide tools. FEM modeling of the temperature profile on the friction surface was performed for wet machining conditions under varying cutting parameters. Comprehensive characterization of the TiB2 coated vs. uncoated cutting tool wear performance was made using optical 3D imaging, SEM/EDX and XPS methods respectively. The results obtained were linked to the FEM modeling. The studies carried out show that during machining of the TiAl6V4 alloy, the efficiency of the TiB2 coating application for carbide cutting tools strongly depends on cutting conditions. The TiB2 coating is very efficient under roughing at low speeds (with strong buildup edge formation. In contrast, it shows similar wear performance to the uncoated tool under finishing operations at higher cutting speeds when cratering wear predominates.

  3. One-step synthesis and scale-dependent luminescence properties of 1D Zn0.9Cd0.1S nanostructures prepared by PVD

    International Nuclear Information System (INIS)

    Jin, Changqing; Zhu, Kexin; Jian, Zengyun; Wei, Yongxing; Ge, Chenghai; Peterson, George

    2017-01-01

    1D Zn 0.9 Cd 0.1 S nanostructures were successfully synthesized via one-step physical vapor deposition. The separation of ultraviolet (UV) emission peaks in the cathodoluminescence (CL) curves, taken in combination with x-ray diffraction (XRD) patterns, proves the coexistence of wurtzite and zincblende phases. The diversity of morphology in nanostuctures originates from Au catalyst splitting during the growth process. The similar photoluminescence spectrums at different positions prove that the composition and defect types were homogeneous, and that defect distribution and density have very small fluctuation at the micron scale. In contrast, the CL curves taken from different locations showed that the defect types and distribution were not uniform on the nanoscale level. (paper)

  4. Influência da texturização laser na vida de ferramentas de torneamento revestidas por CVD e PVD

    OpenAIRE

    Davi Neves

    2010-01-01

    Resumo: Uma característica dos revestimentos aplicados nas ferramentas de corte é a adesão. A adesão deficiente libera particulados duros e abrasivos resultantes da fragmentação prematura do revestimento, acelerando o desgaste das superfícies em contato. Na texturização, um laser de pulsos curtos e de alta frequência provoca, na interação com a superfície, uma mudança das propriedades advinda da fusão e ablação de material. Neste processo podem ocorrer a limpeza e a texturização simultâneas d...

  5. System safety education focused on system management

    Science.gov (United States)

    Grose, V. L.

    1971-01-01

    System safety is defined and characteristics of the system are outlined. Some of the principle characteristics include role of humans in hazard analysis, clear language for input and output, system interdependence, self containment, and parallel analysis of elements.

  6. Systems Biology and Health Systems Complexity in;

    NARCIS (Netherlands)

    Donald Combs, C.; Barham, S.R.; Sloot, P.M.A.

    2016-01-01

    Systems biology addresses interactions in biological systems at different scales of biological organization, from the molecular to the cellular, organ, organism, societal, and ecosystem levels. This chapter expands on the concept of systems biology, explores its implications for individual patients

  7. Airport Information Retrieval System (AIRS) System Design

    Science.gov (United States)

    1974-07-01

    This report presents the system design for a prototype air traffic flow control automation system developed for the FAA's Systems Command Center. The design was directed toward the immediate automation of airport data for use in traffic load predicti...

  8. System specifications for the NDS Dictionary System

    International Nuclear Information System (INIS)

    Attree, P.M.; Smith, P.M.

    1979-09-01

    The NDS Dictionary System is a computerized system for maintaining and distributing the EXFOR dictionaries and for preparing internal versions of these dictionaries for use in the NDS EXFOR System and other NDS systems. This document is an internal manual for the system specifications of the NDS Dictionary System. It includes flow charts, system and program summaries, input and output specifications and file and record descriptions. This manual is updated from time to time when system modifications are made; this is the version of January 1979

  9. Comorbidities Among Women With Vulvovaginal Complaints in Family Practice

    NARCIS (Netherlands)

    Leusink, P.M.; Kaptheijns, A.; Laan, E; Boven, K. van; Lagro-Janssen, A.

    2016-01-01

    BACKGROUND: The lifetime prevalence of women suffering from provoked vestibulodynia (PVD) is estimated to be approximately 15%. The etiology of PVD is not yet clear. Recent studies approach PVD as a chronic multifactorial sexual pain disorder. PVD is associated with pain syndromes, genital

  10. Data of evolutionary structure change: 1PVDA-2VBFA [Confc[Archive

    Lifescience Database Archive (English)

    Full Text Available 1PVDA-2VBFA 1PVD 2VBF A A SEITLGKYLFERLKQVNVNTVFGLPGDFNLSLLDKIYEV...YMADGYARTKKAAAFLTTFGVGELSAINGLAGSYAENLPVVEIVGSPTSKVQNDGKFVHHTLADGDFKHFMKMHEPVTAARTLLT-AENATYEIDRVLSQLLKERKPVYINLPVD...ment> 0 1PVD A 1PVD... ASN CA 268 ALA CA 373 THR CA 367 1PVD... A 1PVDA

  11. Comorbidities Among Women With Vulvovaginal Complaints in Family Practice

    NARCIS (Netherlands)

    Leusink, Peter; Kaptheijns, Anne; Laan, Ellen; van Boven, Kees; Lagro-Janssen, Antoine

    2016-01-01

    Background: The lifetime prevalence of women suffering from provoked vestibulodynia (PVD) is estimated to be approximately 15%. The etiology of PVD is not yet clear. Recent studies approach PVD as a chronic multifactorial sexual pain disorder. PVD is associated with pain syndromes, genital

  12. Data of evolutionary structure change: 1PVDB-2NXWA [Confc[Archive

    Lifescience Database Archive (English)

    Full Text Available 1PVDB-2NXWA 1PVD 2NXW B A SEITLGKYLFERLKQVNVNTVFGLPGDFNLSLLDKIYEV...DAAARYSSTLGVAAVTYGAGAFNMVNAVAGAYAEKSPVVVISGAPGTTEGGL---LLDTQFQVFKEITVAQARLDDPAKAPAEIARVLGAARAQSRPVYLEIPRNMVNAEVE------PVG-DDPAWPVD...indel> 0 1PVD B 1PVD...rmsd> 1.6578389406204224 1 1PVD... B 1PVDB EQHPR-YGGVY

  13. Quality management system

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Mu Sung

    2009-08-15

    This book deals with ISO9001 quality management system which includes summary of this system such as classification of quality, principle of quality management, and definition, requirement and procedure of quality management system, introduction of ISO9001 system like model of ISO9001 quality management system, ISO certificate system, structure of ISO9001 standard, requirement of ISO9001 quality management system, process approach and documentation of system, propel cases of ISO9001 quality management system.

  14. Quality management system

    International Nuclear Information System (INIS)

    Lee, Mu Sung

    2009-08-01

    This book deals with ISO9001 quality management system which includes summary of this system such as classification of quality, principle of quality management, and definition, requirement and procedure of quality management system, introduction of ISO9001 system like model of ISO9001 quality management system, ISO certificate system, structure of ISO9001 standard, requirement of ISO9001 quality management system, process approach and documentation of system, propel cases of ISO9001 quality management system.

  15. Protecting Information in Systems of Systems

    NARCIS (Netherlands)

    Trivellato, Daniel; Zannone, Nicola; Etalle, Sandro

    2011-01-01

    Systems of Systems (SoS) are dynamic, distributed coalitions of autonomous and heterogeneous systems that collaborate to achieve a common goal. While offering several advantages in terms of scalability and flexibility, the SoS paradigm has a strong impact on system interoperability and on the

  16. A security framework for systems of systems

    NARCIS (Netherlands)

    Trivellato, D.; Zannone, N.; Etalle, S.

    2011-01-01

    Systems of systems consist of a wide variety of dynamic, distributed coalitions of autonomous and heterogeneous systems that collaborate to achieve a common goal. While offering several advantages in terms of scalability and flexibility, this new paradigm has a strong impact on system

  17. A Security Framework for Systems of Systems

    NARCIS (Netherlands)

    Trivellato, Daniel; Zannone, Nicola; Etalle, Sandro

    2011-01-01

    Systems of systems consist of a wide variety of dynamic, distributed coalitions of autonomous and heterogeneous systems that collaborate to achieve a common goal. While offering several advantages in terms of scalability and flexibility, this new paradigm has a strong impact on system

  18. Systems theory of interconnected port contact systems

    NARCIS (Netherlands)

    Eberard, D.; Maschke, B.M.; Schaft, A.J. van der

    2005-01-01

    Port-based network modeling of a large class of complex physical systems leads to dynamical systems known as port-Hamiltonian systems. The key ingredient of any port-Hamiltonian system is a power-conserving interconnection structure (mathematically formalized by the geometric notion of a Dirac

  19. Digital processing data communication systems (bus systems)

    International Nuclear Information System (INIS)

    Fleck, K.

    1980-01-01

    After an introduction to the technology of digital processing data communication systems there are the following chapters: digital communication of processing data in automation technology, the technology of biserial communication, the implementaiton of a bus system, the data transmission of the TDC-2000 system of Honeywell's and the process bus CS 275 in the automation system TELEPERM M of Siemens AG. (WB) [de

  20. Networked control of microgrid system of systems

    Science.gov (United States)

    Mahmoud, Magdi S.; Rahman, Mohamed Saif Ur; AL-Sunni, Fouad M.

    2016-08-01

    The microgrid has made its mark in distributed generation and has attracted widespread research. However, microgrid is a complex system which needs to be viewed from an intelligent system of systems perspective. In this paper, a network control system of systems is designed for the islanded microgrid system consisting of three distributed generation units as three subsystems supplying a load. The controller stabilises the microgrid system in the presence of communication infractions such as packet dropouts and delays. Simulation results are included to elucidate the effectiveness of the proposed control strategy.

  1. D0 Cryo System Control System Autodialer

    Energy Technology Data Exchange (ETDEWEB)

    Urbin, J.; /Fermilab

    1990-04-17

    The DO cryogenic system is controlled by a TI565-PLC based control system. This allows the system to be unmanned when in steady state operation. System experts will need to be contacted when system parameters exceed normal operating points and reach alarm setpoints. The labwide FIRUS system provides one alarm monitor and communication link. An autodialer provides a second and more flexible alarm monitor and communication link. The autodialer monitors contact points in the control system and after receiving indication of an alarm accesses a list of experts which it calls until it receives an acknowledgement. There are several manufacturers and distributors of autodialer systems. This EN explains the search process the DO cryo group used to fmd an autodialer system that fit the cryo system's needs and includes information and specs for the unit we chose.

  2. Superspeed Maglev system Transrapid. System decription

    Energy Technology Data Exchange (ETDEWEB)

    Miller, L [Thyssen Henschel AG,, Maglev Transportation Technology, Muenchen (Germany)

    1996-12-31

    The superspeed maglev system Transrapid is a track-bound transportation system for passengern and priority freight transport. The transrapid trainsets are composed of self-sufficient vehicle section coupled together. The superspeed maglev system Transrapid is capable of revenue operation at speeds of 100 to 500 km/h. Besides the description of the system concept and system characteristics safety and availability are discussed. (HW)

  3. Coating system to permit direct brazing of ceramics

    Science.gov (United States)

    Cadden, Charles H.; Hosking, F. Michael

    2003-01-01

    This invention relates to a method for preparing the surface of a ceramic component that enables direct brazing using a non-active braze alloy. The present invention also relates to a method for directly brazing a ceramic component to a ceramic or metal member using this method of surface preparation, and to articles produced by using this brazing method. The ceramic can be high purity alumina. The method comprises applying a first coating of a silicon-bearing oxide material (e.g. silicon dioxide or mullite (3Al.sub.2 O.sub.3.2SiO.sub.2) to the ceramic. Next, a thin coating of active metal (e.g. Ti or V) is applied. Finally, a thicker coating of a non-active metal (e.g. Au or Cu) is applied. The coatings can be applied by physical vapor deposition (PVD). Alternatively, the active and non-active metals can be co-deposited (e.g. by sputtering a target made of mullite). After all of the coatings have been applied, the ceramic can be fired at a high temperature in a non-oxidizing environment to promote diffusion, and to enhance bonding of the coatings to the substrate. After firing, the metallized ceramic component can be brazed to other components using a conventional non-active braze alloy. Alternatively, the firing and brazing steps can be combined into a single step. This process can replace the need to perform a "moly-manganese" metallization step.

  4. System design specification Brayton Isotope Power System (BIPS) Flight System (FS), and Ground Demonstration System (GDS)

    International Nuclear Information System (INIS)

    1976-01-01

    The system design specification for ground demonstration, development, and flight qualification of a Brayton Isotope Power System (BIPS) is presented. The requirements for both a BIPS conceptual Flight System (FS) and a Ground Demonstration System (GDS) are defined

  5. Situation awareness with systems of systems

    CERN Document Server

    Tretmans, Jan; Borth, Michael

    2013-01-01

    This book discusses various aspects, challenges, and solutions for developing systems-of-systems for situation awareness, using applications in the domain of maritime safety and security.  Topics include advanced, multi-objective visualization methods for situation awareness, stochastic outlier selection, rule-based anomaly detection, an ontology-based event model for semantic reasoning, new methods for semi-automatic generation of adapters bridging communication gaps, security policies for systems-of-systems, trust assessment, and methods to deal with the dynamics of systems-of-systems in run-time monitoring, testing, and diagnosis. Architectural considerations for designing information-centric systems-of-systems such as situation awareness systems, and an integrated demonstrator implementing many of the investigated aspects, complete the book.

  6. System specifications for the NDS EXFOR System

    International Nuclear Information System (INIS)

    Attree, P.M.; Smith, P.M.

    1979-07-01

    EXFOR is the agreed exchange format for the magnetic-tape exchange of nuclear reaction data between national and international nuclear data centres for the benefit of nuclear data users in all countries. The NDS EXFOR System is a computerized system for the storage and retrieval of EXFOR information compiled or received by the IAEA. This document is an internal manual for the system specifications of the NDS EXFOR System. It includes flow charts, system and program summaries, input and output specifications and file and record descriptions. The manual is updated from time to time when system modifications are made

  7. System specifications for the NDS EXFOR System

    Energy Technology Data Exchange (ETDEWEB)

    Attree, P M; Smith, P M

    1982-06-01

    EXFOR is the agreed exchange format for the magnetic-tape exchange of nuclear reaction data between national and international nuclear data centers for the benefit of nuclear data users in all countries. The NDS EXFOR System is a computerized system for the storage and retrieval of EXFOR information compiled or received of the IAEA. This document is an internal manual for the system specifications of the NDS EXFOR System. It includes flow charts, system and program summaries, input and output specifications and file and record descriptions. The manual is updated from time to time when system modifications are made; the first version was issued in July 1979. (author)

  8. Computer System Design System-on-Chip

    CERN Document Server

    Flynn, Michael J

    2011-01-01

    The next generation of computer system designers will be less concerned about details of processors and memories, and more concerned about the elements of a system tailored to particular applications. These designers will have a fundamental knowledge of processors and other elements in the system, but the success of their design will depend on the skills in making system-level tradeoffs that optimize the cost, performance and other attributes to meet application requirements. This book provides a new treatment of computer system design, particularly for System-on-Chip (SOC), which addresses th

  9. Smart electromechanical systems the central nervous system

    CERN Document Server

    Kurbanov, Vugar

    2017-01-01

    This book describes approaches to solving the problems of developing the central nervous system of robots (CNSR) based on smart electromechanical systems (SEMS) modules, principles of construction of the various modules of the central nervous system and variants of mathematical software CNSR in control systems for intelligent robots. It presents the latest advances in theory and practice at the Russian Academy of Sciences. Developers of intelligent robots to solve modern problems in robotics are increasingly addressing the use of the bionic approach to create robots that mimic the complexity and adaptability of biological systems. These have smart electromechanical system (SEMS), which are used in various cyber-physical systems (CPhS), and allow the functions of calculation, control, communications, information storage, monitoring, measurement and control of parameters and environmental parameters to be integrated. The behavior of such systems is based on the information received from the central nervous syst...

  10. Multiobjective Collaborative Optimization of Systems of Systems

    National Research Council Canada - National Science Library

    Wolf, Robert A

    2005-01-01

    ...; in other words an inefficient design of the system of systems. This thesis examines the simultaneous design of several ships using the sea base concept as an example application of a network of ships working together...

  11. Situation Awareness with Systems of Systems

    NARCIS (Netherlands)

    Laar, P. van de; Tretmans, J.; Borth, M.

    2013-01-01

    This book discusses various aspects, challenges, and solutions for developing systems-of-systems for situation awareness, using applications in the domain of maritime safety and security. Topics include advanced, multi-objective visualization methods for situation awareness, stochastic outlier

  12. Linking Political Systems and War Systems

    DEFF Research Database (Denmark)

    Harste, Gorm

    2009-01-01

    Decisive parts of the Western political system have demonstrated a seemingly surprising misinterpretation of military might. As Madelaine Albright has suggested, the mighty perceived themselves as "almighty". Political power seems to have invested in instrumental coercive power relations and found...... military coercion to be the appropriate mean. Using the system theory and the theory of systemic risks displayed by the German sociologist Niklas Luhmann the article demonstrates how military systems due to their own autonomy and autopoiesis do not fit into the idea of political government....... The Clausewitzian ideal of a political system that could continue its power games by means of war was moderated by Clausewitz' own analysis of "friction". How can a political system be so blind towards the possibilities of another system? What are the risks of systemic blind spots? The argument of the paper...

  13. Designing information systems

    CERN Document Server

    Blethyn, Stanley G

    2014-01-01

    Designing Information Systems focuses on the processes, methodologies, and approaches involved in designing information systems. The book first describes systems, management and control, and how to design information systems. Discussions focus on documents produced from the functional construction function, users, operators, analysts, programmers and others, process management and control, levels of management, open systems, design of management information systems, and business system description, partitioning, and leveling. The text then takes a look at functional specification and functiona

  14. Cognitive Medical Multiagent Systems

    OpenAIRE

    Barna Iantovics

    2010-01-01

    The development of efficient and flexible agent-based medical diagnosis systems represents a recent research direction. Medical multiagent systems may improve the efficiency of traditionally developed medical computational systems, like the medical expert systems. In our previous researches, a novel cooperative medical diagnosis multiagent system called CMDS (Contract Net Based Medical Diagnosis System) was proposed. CMDS system can solve flexibly a large variety of medical diagnosis problems...

  15. Non linear system become linear system

    Directory of Open Access Journals (Sweden)

    Petre Bucur

    2007-01-01

    Full Text Available The present paper refers to the theory and the practice of the systems regarding non-linear systems and their applications. We aimed the integration of these systems to elaborate their response as well as to highlight some outstanding features.

  16. System Design of the SWRL Financial System.

    Science.gov (United States)

    Ikeda, Masumi

    To produce various management and accounting reports in order to maintain control of SWRL (Southwest Regional Laboratory) operational and financial activities, a computer-based SWRL financial system was developed. The system design is outlined, and various types of system inputs described. The kinds of management and accounting reports generated…

  17. Triggering system innovation in agricultural innovation systems

    NARCIS (Netherlands)

    Turner, James A.; Williams, Tracy; Nicholas, Graeme; Foote, Jeff; Rijswijk, Kelly; Barnard, Tim; Beechener, Sam; Horita, Akiko

    2017-01-01

    This article describes a process for stimulating engagement among change agents to develop a shared understanding of systemic problems in the agricultural innovation system (AIS), challenge prevalent institutional logics and identify actions they might undertake to stimulate system innovation.

  18. Port contact systems for irreversible thermodynamical systems

    NARCIS (Netherlands)

    Eberard, D.; Maschke, B.M.; Schaft, A.J. van der

    2005-01-01

    In this paper we propose a definition of control contact systems, generalizing input-output Hamiltonian systems, to cope with models arising from irreversible Thermodynamics. We exhibit a particular subclass of these systems, called conservative, that leaves invariant some Legendre submanifold (the

  19. Modeling learning technology systems as business systems

    NARCIS (Netherlands)

    Avgeriou, Paris; Retalis, Symeon; Papaspyrou, Nikolaos

    2003-01-01

    The design of Learning Technology Systems, and the Software Systems that support them, is largely conducted on an intuitive, ad hoc basis, thus resulting in inefficient systems that defectively support the learning process. There is now justifiable, increasing effort in formalizing the engineering

  20. General Systems Theory and Instructional Systems Design.

    Science.gov (United States)

    Salisbury, David F.

    1990-01-01

    Describes basic concepts in the field of general systems theory (GST) and identifies commonalities that exist between GST and instructional systems design (ISD). Models and diagrams that depict system elements in ISD are presented, and two matrices that show how GST has been used in ISD literature are included. (11 references) (LRW)

  1. Expert systems in process control systems

    International Nuclear Information System (INIS)

    Wittig, T.

    1987-01-01

    To illustrate where the fundamental difference between expert systems in classical diagnosis and in industrial control lie, the work of process control instrumentation is used as an example for the job of expert systems. Starting from the general process of problem-solving, two classes of expert systems can be defined accordingly. (orig.) [de

  2. Expert Systems for auditing management information systems

    Directory of Open Access Journals (Sweden)

    Gheroghe Popescu

    2007-05-01

    Full Text Available Expert systems are built with the help of: specialised programming languages or expert system generators (shell. But this structure was reached after tens of years of work and research, because expert systems are nothing but pragmatic capitalisation of the results of research carried out in artificial intelligence and theory of knowledge.

  3. Tribo-electrochemical characterization of hafnium multilayer systems deposited on nitride/vanadium nitride AISI 4140 steel

    Science.gov (United States)

    Mora, M.; Vera, E.; Aperador, W.

    2016-02-01

    In this work is presented the synergistic behaviour among corrosion/wear (tribocorrosion) of the multilayer coatings hafnium nitride/vanadium nitride [HfN/VN]n. The multilayers were deposited on AISI 4140 steel using the technique of physical vapor deposition PVD magnetron sputtering, the tests were performed using a pin-on-disk tribometer, which has an adapted potentiostat galvanostat with three-electrode electrochemical cell. Tribocorrosive parameters such as: Friction coefficient between the coating and the counter body (100 Cr6 steel ball); Polarization resistance by means of electrochemical impedance spectroscopy technique and corrosion rate by polarization curves were determined. It was observed an increase in the polarization resistance, a decrease in the corrosion rate and a low coefficient of friction in comparison with the substrate, due to an increase on the number of bilayers.

  4. Tribo-electrochemical characterization of hafnium multilayer systems deposited on nitride/vanadium nitride AISI 4140 steel

    International Nuclear Information System (INIS)

    Mora, M; Vera, E; Aperador, W

    2016-01-01

    In this work is presented the synergistic behaviour among corrosion/wear (tribocorrosion) of the multilayer coatings hafnium nitride/vanadium nitride [HfN/VN]n. The multilayers were deposited on AISI 4140 steel using the technique of physical vapor deposition PVD magnetron sputtering, the tests were performed using a pin-on-disk tribometer, which has an adapted potentiostat galvanostat with three-electrode electrochemical cell. Tribocorrosive parameters such as: Friction coefficient between the coating and the counter body (100 Cr6 steel ball); Polarization resistance by means of electrochemical impedance spectroscopy technique and corrosion rate by polarization curves were determined. It was observed an increase in the polarization resistance, a decrease in the corrosion rate and a low coefficient of friction in comparison with the substrate, due to an increase on the number of bilayers. (paper)

  5. Psychology of system design

    CERN Document Server

    Meister, D

    2014-01-01

    This is a book about systems, including: systems in which humans control machines; systems in which humans interact with humans and the machine component is relatively unimportant; systems which are heavily computerized and those that are not; and governmental, industrial, military and social systems. The book deals with both traditional systems like farming, fishing and the military, and with systems just now tentatively emerging, like the expert and the interactive computer system. The emphasis is on the system concept and its implications for analysis, design and evaluation of these many di

  6. Biomedical signals and systems

    CERN Document Server

    Tranquillo, Joseph V

    2013-01-01

    Biomedical Signals and Systems is meant to accompany a one-semester undergraduate signals and systems course. It may also serve as a quick-start for graduate students or faculty interested in how signals and systems techniques can be applied to living systems. The biological nature of the examples allows for systems thinking to be applied to electrical, mechanical, fluid, chemical, thermal and even optical systems. Each chapter focuses on a topic from classic signals and systems theory: System block diagrams, mathematical models, transforms, stability, feedback, system response, control, time

  7. Operating System Security

    CERN Document Server

    Jaeger, Trent

    2008-01-01

    Operating systems provide the fundamental mechanisms for securing computer processing. Since the 1960s, operating systems designers have explored how to build "secure" operating systems - operating systems whose mechanisms protect the system against a motivated adversary. Recently, the importance of ensuring such security has become a mainstream issue for all operating systems. In this book, we examine past research that outlines the requirements for a secure operating system and research that implements example systems that aim for such requirements. For system designs that aimed to

  8. Systems Measures of Water Distribution System Resilience

    Energy Technology Data Exchange (ETDEWEB)

    Klise, Katherine A. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Murray, Regan [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Walker, La Tonya Nicole [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

    2015-01-01

    Resilience is a concept that is being used increasingly to refer to the capacity of infrastructure systems to be prepared for and able to respond effectively and rapidly to hazardous events. In Section 2 of this report, drinking water hazards, resilience literature, and available resilience tools are presented. Broader definitions, attributes and methods for measuring resilience are presented in Section 3. In Section 4, quantitative systems performance measures for water distribution systems are presented. Finally, in Section 5, the performance measures and their relevance to measuring the resilience of water systems to hazards is discussed along with needed improvements to water distribution system modeling tools.

  9. Manager's assistant systems for space system planning

    Science.gov (United States)

    Bewley, William L.; Burnard, Robert; Edwards, Gary E.; Shoop, James

    1992-01-01

    This paper describes a class of knowledge-based 'assistant' systems for space system planning. Derived from technology produced for the DARPA/USAF Pilot's Associate program, these assistant systems help the human planner by doing the bookkeeping to maintain plan data and executing the procedures and heuristics currently used by the human planner to define, assess, diagnose, and revise plans. Intelligent systems for Space Station Freedom assembly sequence planning and Advanced Launch System modeling will be presented as examples. Ongoing NASA-funded work on a framework supporting the development of such tools will also be described.

  10. Lighting system with thermal management system

    Science.gov (United States)

    Arik, Mehmet; Weaver, Stanton; Stecher, Thomas; Seeley, Charles; Kuenzler, Glenn; Wolfe, Jr., Charles; Utturkar, Yogen; Sharma, Rajdeep; Prabhakaran, Satish; Icoz, Tunc

    2013-05-07

    Lighting systems having unique configurations are provided. For instance, the lighting system may include a light source, a thermal management system and driver electronics, each contained within a housing structure. The light source is configured to provide illumination visible through an opening in the housing structure. The thermal management system is configured to provide an air flow, such as a unidirectional air flow, through the housing structure in order to cool the light source. The driver electronics are configured to provide power to each of the light source and the thermal management system.

  11. EPICS based DAQ system

    International Nuclear Information System (INIS)

    Cheng Weixing; Chen Yongzhong; Zhou Weimin; Ye Kairong; Liu Dekang

    2002-01-01

    EPICS is the most popular developing platform to build control system and beam diagnostic system in modern physics experiment facilities. An EPICS based data acquisition system was built in Redhat 6.2 operation system. The system is successfully used in the beam position monitor mapping, it improves the mapping process a lot

  12. Autonomous photovoltaic lighting system

    OpenAIRE

    Hafez, Ahmed A. A.; Montesinos Miracle, Daniel; Sudrià Andreu, Antoni

    2012-01-01

    This paper introduces a comparison between the conventional and Photovoltaic (PV) lighting systems. A simple sizing procedure for a PV stand-alone system was advised. The paper also proposes a novel PV lighting system. The proposed system is simple, compact and reliable. The system operation was investigated by thoroughly mathematical and simulation work.

  13. FFTF control system experience

    International Nuclear Information System (INIS)

    Warrick, R.P.

    1981-01-01

    The FFTF control systems provide control equipment for safe and efficient operation of the plant. For convenience, these systems will be divided into three parts for discussions: (1) Plant Protection System (PPS); (2) Plant Control System (PCS); and (3) General Observations. Performance of each of these systems is discussed

  14. Automatic control systems engineering

    International Nuclear Information System (INIS)

    Shin, Yun Gi

    2004-01-01

    This book gives descriptions of automatic control for electrical electronics, which indicates history of automatic control, Laplace transform, block diagram and signal flow diagram, electrometer, linearization of system, space of situation, state space analysis of electric system, sensor, hydro controlling system, stability, time response of linear dynamic system, conception of root locus, procedure to draw root locus, frequency response, and design of control system.

  15. MEA vacuum system

    International Nuclear Information System (INIS)

    Stroo, R.; Schwebke, H.; Heine, E.

    1984-01-01

    This report describes construction and operation of the MEA vacuum system of NIKHEF (Netherlands). First, the klystron vacuum system, beam transport system, diode pump and a triode pump are described. Next, the isolation valve and the fast valves of the vacuum system are considered. Measuring instruments, vacuum system commands and messages of failures are treated in the last chapter. (G.J.P.)

  16. From systems biology to systems biomedicine.

    Science.gov (United States)

    Antony, Paul M A; Balling, Rudi; Vlassis, Nikos

    2012-08-01

    Systems Biology is about combining theory, technology, and targeted experiments in a way that drives not only data accumulation but knowledge as well. The challenge in Systems Biomedicine is to furthermore translate mechanistic insights in biological systems to clinical application, with the central aim of improving patients' quality of life. The challenge is to find theoretically well-chosen models for the contextually correct and intelligible representation of multi-scale biological systems. In this review, we discuss the current state of Systems Biology, highlight the emergence of Systems Biomedicine, and highlight some of the topics and views that we think are important for the efficient application of Systems Theory in Biomedicine. Copyright © 2011 Elsevier Ltd. All rights reserved.

  17. Mapping biological systems to network systems

    CERN Document Server

    Rathore, Heena

    2016-01-01

    The book presents the challenges inherent in the paradigm shift of network systems from static to highly dynamic distributed systems – it proposes solutions that the symbiotic nature of biological systems can provide into altering networking systems to adapt to these changes. The author discuss how biological systems – which have the inherent capabilities of evolving, self-organizing, self-repairing and flourishing with time – are inspiring researchers to take opportunities from the biology domain and map them with the problems faced in network domain. The book revolves around the central idea of bio-inspired systems -- it begins by exploring why biology and computer network research are such a natural match. This is followed by presenting a broad overview of biologically inspired research in network systems -- it is classified by the biological field that inspired each topic and by the area of networking in which that topic lies. Each case elucidates how biological concepts have been most successfully ...

  18. Environmental Management System

    Science.gov (United States)

    Goals Recycling Green Purchasing Pollution Prevention Reusing Water Resources Environmental Management Stewardship » Environmental Protection » Environmental Management System Environmental Management System An Environmental Management System is a systematic method for assessing mission activities, determining the

  19. System floorplanning optimization

    KAUST Repository

    Browning, David W.; Elansary, Ayman; Shalaby, Mohamed

    2012-01-01

    Notebook and Laptop Original Equipment Manufacturers (OEMs) place great emphasis on creating unique system designs to differentiate themselves in the mobile market. These systems are developed from the 'outside in' with the focus on how the system

  20. Connected motorcycle system performance.

    Science.gov (United States)

    2016-01-15

    This project characterized the performance of Connected Vehicle Systems (CVS) on motorcycles based on two key components: global positioning and wireless communication systems. Considering that Global Positioning System (GPS) and 5.9 GHz Dedicated Sh...