Sample records for zirconate titanate pzt

  1. A Ferroelastic Switching Model for Lead Zirconate-Titanate (PZT)

    E-print Network

    A Ferroelastic Switching Model for Lead Zirconate-Titanate (PZT) Brian L. Ball1 , Ralph C. Smith2 which characterizes the ferroelastic switching mechanisms inherent to lead zirconate-titanate (PZT and prediction of experimental PLZT data. 2 Ferroelectric and Ferroelastic Switching Mechanisms Lead zirconate

  2. Electrophoretic deposition (EPD) process for lead zirconate titanate (PZT) thick films fabrication and high

    E-print Network

    Boyer, Edmond

    Electrophoretic deposition (EPD) process for lead zirconate titanate (PZT) thick films fabrication lead-zirconate titanate (PZT) thick films were fabricated on non-flat substrate by electrophoretic, the sensitivity and spatial resolution (axial). Lead zirconate titanate (PZT) is commonly used as piezoelectric

  3. Fabrication and performance of d33-mode lead-zirconate-titanate (PZT) MEMS accelerometers

    NASA Astrophysics Data System (ADS)

    Yu, Han G.; Wolf, Richard; Deng, Kan; Zou, Lichun; Tadigadapa, Srinivas; Troilier-McKinstry, Susan

    2001-10-01

    Piezoelectric accelerometers fabricated from Lead-Zirconate-Titanate (PZT) thin films are expected to achieve higher sensitivities and better signal-to-noise ratios (SNR) in comparison with capacitive and piezoresistive accelerometers. This paper will present, for the first time, the fabrication and performance of piezoelectric, bulk-micromachined accelerometers using PZT thin films operating in the d33-mode. Using sol-gel techniques, 0.6 mm thick PZT films with high piezoelectric coefficients were deposited. Measurements on these PZT films show a remnant polarization Pr < 19 (mu) C/cm2, dielectric constants Er > 800, and d33 coefficient of 120 pC/N. The PZT accelerometers operating in the d33 mode were successfully fabricated. Interdigitated capacitors were used to achieve the d33 mode of operation and deep reactive ion etching was used to define the proof-mass of the accelerometers. Measurements on these accelerometers show sensitivities ranging from 0.85 - 1.67 mV/g with resonance frequencies ranging from 22.4 - 15.4 kHz respectively. In addition to the improved sensitivity, advantages of d33-mode accelerometers include use of thinner PZT films, and the ability to optimize the impedance of the device to achieve a higher SNR. The performance of MEMS d33-mode accelerometers will also be compare with the previously reported d31-mode accelerometers using PZT thin films.

  4. Microelectromechanical systems (MEMS) sensors based on lead zirconate titanate (PZT) films

    NASA Astrophysics Data System (ADS)

    Wang, Li-Peng

    2001-12-01

    In this thesis, modeling, fabrication and testing of microelectromechanical systems (MEMS) accelerometers based on piezoelectric lead zirconate titanate (PZT) films are investigated. Three different types of structures, cantilever beam, trampoline, and annular diaphragm, are studied. It demonstrates the high-performance, miniaturate, mass-production-compatible, and potentially circuitry-integratable piezoelectric-type PZT MEMS devices. Theoretical models of the cantilever-beam and trampoline accelerometers are derived via structural dynamics and the constitutive equations of piezoelectricity. The time-dependent transverse vibration equations, mode shapes, resonant frequencies, and sensitivities of the accelerometers are calculated through the models. Optimization of the silicon and PZT thickness is achieved with considering the effects of the structural dynamics, the material properties, and manufacturability for different accelerometer specifications. This work is the first demonstration of the fabrication of bulk-micromachined accelerometers combining a deep-trench reactive ion etching (DRIE) release strategy and thick piezoelectric PZT films deposited using a sol-gel method. Processing challenges which are overcome included materials compatibility, metallization, processing of thick layers, double-side processing, deep-trench silicon etching, post-etch cleaning and process integration. In addition, the processed PZT films are characterized by dielectric, ferroelectric (polarization electric-field hysteresis), and piezoelectric measurements and no adverse effects are found. Dynamic frequency response and impedance resonance measurements are performed to ascertain the performance of the MEMS accelerometers. The results show high sensitivities and broad frequency ranges of the piezoelectric-type PZT MEMS accelerometers; the sensitivities range from 0.1 to 7.6 pC/g for resonant frequencies ranging from 44.3 kHz to 3.7 kHz. The sensitivities were compared to theoretical values and a reasonable agreement (˜36% difference) is obtained.

  5. Mechanical and dielectric characterization of lead zirconate titanate(PZT)/polyurethane(PU) thin film composite for energy harvesting

    NASA Astrophysics Data System (ADS)

    Aboubakr, S.; Rguiti, M.; Hajjaji, A.; Eddiai, A.; Courtois, C.; d'Astorg, S.

    2014-04-01

    The Lead Zirconate titanate (PZT) ceramic is known by its piezoelectric feature, but also by its stiffness, the use of a composite based on a polyurethane (PU) matrix charged by a piezoelectric material, enable to generate a large deformation of the material, therefore harvesting more energy. This new material will provide a competitive alternative and low cost manufacturing technology of autonomous systems (smart clothes, car seat, boat sail, flag ...). A thin film of the PZT/PU composite was prepared using up to 80 vol. % of ceramic. Due to the dielectric nature of the PZT, inclusions of this one in a PU matrix raises the permittivity of the composite, on other hand this latter seems to decline at high frequencies.

  6. High rejection, tunable parallel resonance in micromachined lead zirconate titanate on silicon resonators

    E-print Network

    Afshari, Ehsan

    High rejection, tunable parallel resonance in micromachined lead zirconate titanate on silicon; published online 9 September 2011) This paper presents a micromachined lead zirconate titanate-film lead zirconate titanate (PZT) resonator work,10 where improved series resonance motional resistance

  7. Electrophoretic deposition of lead zirconate titanate (PZT) powder from ethanol suspension prepared with phosphate ester

    Microsoft Academic Search

    Saengdoen Doungdaw; Tetsuo Uchikoshi; Yuji Noguchi; Chutima Eamchotchawalit; Yoshio Sakka

    2005-01-01

    The formation of thick PZT films via electrophoretic deposition (EPD) was studied. The colloidal suspension of a nano-sized PZT powder dispersed in ethanol was prepared using a phosphate ester (PE) as a dispersant. The amount of PE addition on the stability of the PZT suspension has been investigated by measuring the pH and conductivity of the suspension, deposition weight and

  8. Using the methods of radiospectroscopy (EPR, NMR) to study the nature of the defect structure of solid solutions based on lead zirconate titanate (PZT).

    PubMed

    Bykov, Igor; Zagorodniy, Yuriy; Yurchenko, Lesya; Korduban, Alexander; Nejezchleb, Karel; Trachevsky, Vladimir; Dimza, Vilnis; Jastrabik, Lubomir; Dejneka, Alexander

    2014-08-01

    The nature of intrinsic and impurity point defects in lead zirconate titanate (PZT) ceramics has been explored. Using electron paramagnetic resonance (EPR), nuclear magnetic resonance (NMR), and X-ray photoelectron spectroscopy (XPS) methods, several impurity sites have been identified in the materials, including the Fe(3+)-oxygen vacancy (VO) complex and Pb ions. Both of these centers are incorporated into the PZT lattice. The Fe(3+) –V? paramagnetic complex serves as a sensitive probe of the local crystal field in the ceramic; the symmetry of this defect roughly correlates with PZT phase diagram as the composition is varied from PbTiO3 to PbZrO3. NMR spectra (207)Pb in PbTiO3, PbZrO3, and PZT with iron content from 0 to 0.4 wt% showed that increasing the iron concentration leads to a distortion of the crystal structure and to improvement of the electrophysical parameters of the piezoceramics. This is due to the formation of a phase which has a higher symmetry, but at high concentrations of iron (>0.4 wt%), it leads to sharp degradation of electrophysical parameters. PMID:25073145

  9. Effects of thickness on the piezoelectric and dielectric properties of lead zirconate titanate thin films

    E-print Network

    Sottos, Nancy R.

    Effects of thickness on the piezoelectric and dielectric properties of lead zirconate titanate thin Lead zirconate titanate PZT thin films with a Zr/Ti ratio of 52/48 were deposited on platinized silicon

  10. Direct printing of lead zirconate titanate thin films

    E-print Network

    Bathurst, Stephen, 1980-

    2008-01-01

    Thus far, use of lead zirconate titanate (PZT) in MEMS has been limited due to the lack of process compatibility with existing MEMS manufacturing techniques. Direct printing of thin films eliminates the need for photolithographic ...

  11. A smart, intermittent driven particle sensor with an airflow change trigger using a lead zirconate titanate (PZT) cantilever

    NASA Astrophysics Data System (ADS)

    Takahashi, Hidetoshi; Tomimatsu, Yutaka; Kobayashi, Takeshi; Isozaki, Akihiro; Itoh, Toshihiro; Maeda, Ryutaro; Matsumoto, Kiyoshi; Shimoyama, Isao

    2014-02-01

    This paper reports on a smart, intermittent driven particle sensor with an airflow trigger. A lead zirconate titanate cantilever functions as the trigger, which detects an airflow change without requiring a power supply to drive the sensing element. Because an airflow change indicates that the particle concentration has changed, the trigger switches the optical particle counter from sleep mode to active mode only when the particle concentration surrounding the sensor changes. The sensor power consumption in sleep mode is 100 times less than that in the active mode. Thus, this intermittent driven method significantly reduces the total power consumption of the particle sensor. In this paper, we fabricate a prototype of the particle sensor and demonstrate that the optical particle counter can be switched on by the fabricated trigger and thus that the particle concentration can be measured.

  12. Neutron irradiation effects on domain wall mobility and reversibility in lead zirconate titanate thin films

    E-print Network

    Ferreira, Paulo J.

    Neutron irradiation effects on domain wall mobility and reversibility in lead zirconate titanate mobility and reversibility in lead zirconate titanate thin films Joseph T. Graham,1,2,a) Geoff L. Brennecka lead zirconate titanate (PZT) were investigated. Two sets of PbZr0:52Ti0:48O3 films of varying initial

  13. Symmetries and multiferroic properties of novel room-temperature magnetoelectrics: Lead iron tantalate – lead zirconate titanate (PFT/PZT)

    DOE PAGESBeta

    Sanchez, Dilsom A.; Ortega, N.; Kumar, Ashok; Roque-Malherbe, R.; Polanco, R.; Scott, J. F.; Katiyar, Ram S.

    2011-01-01

    Mixing 60-70% lead zirconate titanate with 40-30% lead iron tantalate produces a single-phase, low-loss, room-temperature multiferroic with magnetoelectric coupling: (PbZr?.??Ti?.??O?) (1-x)- (PbFe?.?Ta?.?O?)x. The present study combines x-ray scattering, magnetic and polarization hysteresis in both phases, plus a second-order dielectric divergence (to epsilon = 6000 at 475 K for 0.4 PFT; to 4000 at 520 K for 0.3 PFT) for an unambiguous assignment as a C2v-C4v (Pmm2-P4mm) transition. The material exhibits square saturated magnetic hysteresis loops with 0.1 emu/g at 295 K and saturation polarization Pr = 25 ?C/cm², which actually increases (to 40 ?C/cm²) in the high-T tetragonal phase, representing an exciting new room temperature oxide multiferroic to compete with BiFeO?. Additional transitions at high temperatures (cubic at T>1300 K) and low temperatures (rhombohedral or monoclinic at T<250 K) are found. These are the lowest-loss room-temperature multiferroics known, which is a great advantage for magnetoelectric devices.

  14. Symmetries and multiferroic properties of novel room-temperature magnetoelectrics: Lead iron tantalate – lead zirconate titanate (PFT/PZT)

    DOE PAGESBeta

    Sanchez, Dilsom A.; Ortega, N.; Kumar, Ashok; Roque-Malherbe, R.; Polanco, R.; Scott, J. F.; Katiyar, Ram S.

    2011-01-01

    Mixing 60-70% lead zirconate titanate with 40-30% lead iron tantalate produces a single-phase, low-loss, room-temperature multiferroic with magnetoelectric coupling: (PbZr?.??Ti?.??O?) (1-x)- (PbFe?.?Ta?.?O?)x. The present study combines x-ray scattering, magnetic and polarization hysteresis in both phases, plus a second-order dielectric divergence (to epsilon = 6000 at 475 K for 0.4 PFT; to 4000 at 520 K for 0.3 PFT) for an unambiguous assignment as a C2v-C4v (Pmm2-P4mm) transition. The material exhibits square saturated magnetic hysteresis loops with 0.1 emu/g at 295 K and saturation polarization Pr = 25 ?C/cm², which actually increases (to 40 ?C/cm²) in the high-T tetragonal phase, representingmore »an exciting new room temperature oxide multiferroic to compete with BiFeO?. Additional transitions at high temperatures (cubic at T>1300 K) and low temperatures (rhombohedral or monoclinic at T« less

  15. Thermal strain measurement in sol-gel lead zirconate titanate thin films T. A. Berfield,1,a

    E-print Network

    Sottos, Nancy R.

    Thermal strain measurement in sol-gel lead zirconate titanate thin films T. A. Berfield,1,a J. F-plane strain development of blanket sol-gel derived lead zirconate titanate thin films deposited on platinized zirconate titanate PZT , the sol-gel deposition route is particularly attractive as it can lower

  16. Hydrothernal Synthesis and Electric Properties of Fibrous Lead Zirconate Titanate

    Microsoft Academic Search

    D. Y. Tang; X. L. Wu; Y. J. Qiao; L. S. Qiang

    2006-01-01

    Lead zirconate titanate (PZT) powder with fibroid morphology was prepared via hydrothermal synthesis and heat treatment using organic mineralizer, tetramethylammonium hydroxide pentahydrate (TMAH). The structure and morphology of the resultant fibers were investigated by X-ray diffraction (XRD) analysis and transmission electron microscope (TEM) observation, The TMAH concentration, hydrothermal reaction time, calcining temperature, calcining time both had effects on the microstructure

  17. Preparation of lead zirconate titanate nano-powder by electrohydrodynamic atomization

    Microsoft Academic Search

    S. N. Jayasinghe; R. A. Dorey; M. J. Edirisinghe; Z. B. Luklinska

    2005-01-01

    A lead zirconate titanate (PZT) sol was subjected to electrohydrodynamic atomization in the stable cone-jet mode. The droplets generated were sized by laser diffraction before deposition and heating to 600 °C. The droplets were 20 35 mum in size and transmission electron microscopy showed that their relics consisted of PZT powder particles, <10 nm in size. Thus, a novel method

  18. Aluminium coating of lead zirconate titanate—A study of cold spray variables

    Microsoft Academic Search

    Peter C. King; Saden Zahiri; Mahnaz Jahedi; James Friend

    2010-01-01

    Cold spray was used to deposit conductive aluminium coatings onto lead zirconate titanate (PZT) piezoceramics. The optimisation of processing parameters was explored. Grain removal from the PZT surface due to the impact of Al particles was reduced by increasing the average particle velocity. Surface domain reorientation was detected by X-ray diffraction (XRD). Substrate temperatures during spraying were maintained at a

  19. Direct precipitation of lead zirconate titanate by the hydrothermal method

    Microsoft Academic Search

    T. R. N. Kutty; R. Balachandran

    1984-01-01

    Direct precipitation of fine powders of lead zirconate titanate (PZT) in the complete range of solid solution, is investigated under hydrothermal conditions, starting from lead oxide and titania\\/zirconia mixed gels. The perovskite phase is formed in the temperature range of 165 - 340°C. Sequence of the hydrothermal reactions is studied by identifying the intermediate phases. The initial formation of PbO:TiOâ

  20. Adhesion of electrolessly deposited nickel on lead zirconate titanate ceramic

    SciTech Connect

    Baumgartner, C.E. (General Electric Co., Schenectady, NY (United States). Corporate Research and Development Center)

    1989-06-01

    This paper reports on electrolessly deposited Ni onto lead zirconate titanate (PZT) ceramic measured as a function of both the ceramics surface preparation prior to metalization and the plated Ni thickness. A maximum in Ni/PZT interfacial adhesion of approximately 27 kg/cm{sup 2}, as measured by a pull test, occurs when the ceramic grain boundaries are chemically etched, thereby providing points to mechanically anchor the Ni deposit. The adhesion decreases with over-etching as the ceramic grains are undercut and drops off dramatically with increasing plated Ni thickness.

  1. Preparation of lead zirconate titanate nano-powder by electrohydrodynamic atomization

    NASA Astrophysics Data System (ADS)

    Jayasinghe, S. N.; Dorey, R. A.; Edirisinghe, M. J.; Luklinska, Z. B.

    2005-02-01

    A lead zirconate titanate (PZT) sol was subjected to electrohydrodynamic atomization in the stable cone-jet mode. The droplets generated were sized by laser diffraction before deposition and heating to 600 °C. The droplets were 20 35 ?m in size and transmission electron microscopy showed that their relics consisted of PZT powder particles, <10 nm in size. Thus, a novel method of preparing nano-powders of functional advanced materials, such as PZT, has been pioneered.

  2. Direct precipitation of lead zirconate titanate by the hydrothermal method

    SciTech Connect

    Kutty, T.R.N.; Balachandran, R.

    1984-11-01

    Direct precipitation of fine powders of lead zirconate titanate (PZT) in the complete range of solid solution, is investigated under hydrothermal conditions, starting from lead oxide and titania/zirconia mixed gels. The perovskite phase is formed in the temperature range of 165 - 340/sup 0/C. Sequence of the hydrothermal reactions is studied by identifying the intermediate phases. The initial formation of PbO:TiO/sub 2/ solid solution is followed by the reaction of the same with the remaining mixed gels giving rise to X-ray amorphous PZT phase. Further, through crystallite growth, the X-ray crystalline PZT is formed. This method can be extended for the preparation of PLZT powder as well. The resulting powders are sinterable to high density ceramics.

  3. Characterization of lead zirconate titanate ceramics for use in miniature high-frequency (20-80 MHz) transducers

    Microsoft Academic Search

    F. Stuart Foster; Linda K. Ryan; Daniel H. Turnbull

    1991-01-01

    The material properties of lead zirconate titanate (PZT) ceramics for operation in the thickness mode at frequencies as high as 80 MHz are reported. Each of the ceramics tested showed a reduction in k t with increasing frequency. In a fine-grained PZT, values of kt as high as 0.44 were measured at 80 MHz. The effects of grain size were

  4. Fundamental study of hydrothermally synthesized lead zirconate titanate polycrystals deposited on a Ti substrate during nucleation

    NASA Astrophysics Data System (ADS)

    Abe, Toshinobu; Ozeki, Seiya; Kuribayashi Kurosawa, Minoru; Takeuchi, Shinichi

    2015-07-01

    We previously fabricated a piezoelectric transducer from a lead zirconate titanate (PZT) polycrystalline film deposited on a Ti substrate by a hydrothermal synthesis method. However, the hydrothermal synthesis required a long deposition time to achieve the necessary film thickness. In this study, we confirmed that the thickness of the PZT polycrystalline film increased when the solution was stirred at 245 rpm during synthesis, and that the optimum deposition time was 5 h.

  5. Preparation of lead zirconate titanate nano-powder by electrohydrodynamic atomization

    Microsoft Academic Search

    S. N. Jayasinghe; R. A. Dorey; M. J. Edirisinghe; Z. B. Luklinska

    2005-01-01

    A lead zirconate titanate (PZT) sol was subjected to electrohydrodynamic atomization in the stable cone-jet mode. The droplets generated were sized by laser diffraction before deposition and heating to 600 °C. The droplets were 20–35 ?m in size and transmission electron microscopy showed that their relics consisted of PZT powder particles, <10 nm in size. Thus, a novel method of preparing nano-powders of

  6. Local origin of macroscopic properties and patterning in Lead zirconate titanate films

    Microsoft Academic Search

    Patamas Bintachitt

    2009-01-01

    This thesis describes the preparation of high quality lead zirconate titanate (PZT) films, the nonlinearity in their dielectric and piezoelectric responses, as well as their patterning by reactive ion etching. One goal of the research was to obtain {001} oriented PZT films on Pt-coated Si substrates. In this work, PbTiO3 buffer layers were chosen due to good lattice matching with

  7. Electron Emission from Lead-Zirconate-Titanate Ferroelectric Ceramic Induced by Pulse Electric Field

    Microsoft Academic Search

    Masanori Okuyama; Jun-ichi Asano; Yoshihiro Hamakawa

    1994-01-01

    Electron emission into vacuum from a thin plate of lead-zirconate-titanate (PZT) ferroelectric ceramics has been observed under the impression of pulse electric field. Electrons are emitted not only from the ceramic surface near the electrode edge but also through the thin metal electrode. The emitted charge per one pulse little depends on pulse frequency when it is less than 2

  8. Computational investigation of B-site donor doping effect on fatigue behavior of lead zirconate titanate

    NASA Astrophysics Data System (ADS)

    Zhang, Zhen; Lu, Li; Shu, Chang; Wu, Ping

    2006-10-01

    The effect of the B-site donor on the fatigue behavior of lead zirconate titanate (PZT) was studied. Seven elements were considered. The formation energies of oxygen vacancies and band structures of these doped systems were investigated. It was found that the Nb, Ta, and W doped PZT systems have the highest formation energy of oxygen vacancies as well as reduced occupations of Ti 3d states by the electrons released from oxygen vacancies. Therefore, the systems respectively doped with Nb, Ta, and W can effectively improve the fatigue property of PZT.

  9. Neutron diffraction studies on recrystallization of solution derived lead zirconate titanates

    SciTech Connect

    Morosin, B.; Tuttle, B.A.; Voigt, J.A. [Sandia National Labs., Albuquerque, NM (United States); Lawson, A.C. [Los Alamos National Lab., NM (United States); Kwei, G.H. [Lawrence Livermore National Lab., CA (United States)

    1994-12-31

    We performed neutron powder diffraction on solution-derived lead zirconate titanates (PZT). Three compositions, PZT 45/55, PZT 20/80 and PbTiO{sub 3}, were investigated. The materials were annealed so that the perovskite phase had just begun to grow from the precursor phase. In our materials this precursor phase is the pyrochlore rather than fluorite phase. The results show that in the pyrochlore phase, the (Ti,Zr) and the Pb are ordered in their crystallographic sites while the O are essentially disordered in both of the two usual pyrochlore anion sites.

  10. Relationship between orientation factor of lead zirconate titanate nanowires and dielectric permittivity of nanocomposites

    SciTech Connect

    Tang, Haixiong, E-mail: htang15@ufl.edu, E-mail: hsodano@ufl.edu [Department of Materials Science and Engineering, University of Florida, Gainesville, Florida 32611 (United States)] [Department of Materials Science and Engineering, University of Florida, Gainesville, Florida 32611 (United States); Malakooti, Mohammad H. [Department of Mechanical and Aerospace Engineering, University of Florida, Gainesville, Florida 32611 (United States)] [Department of Mechanical and Aerospace Engineering, University of Florida, Gainesville, Florida 32611 (United States); Sodano, Henry A., E-mail: htang15@ufl.edu, E-mail: hsodano@ufl.edu [Department of Materials Science and Engineering, University of Florida, Gainesville, Florida 32611 (United States); Department of Mechanical and Aerospace Engineering, University of Florida, Gainesville, Florida 32611 (United States)

    2013-11-25

    The relationship between the orientation of lead zirconate titanate (PZT) nanowires dispersed in nanocomposites and the resulting dielectric constants are quantified. The orientation of the PZT nanowires embedded in a polymer matrix is controlled by varying the draw ratio and subsequently quantified using Herman's Orientation Factor. Consequently, it is demonstrated that the dielectric constants of nanocomposites are improved by increasing the orientation factor of the PZT nanowires. This technique is proposed to improve the dielectric constant of the nanocomposites without the need for additional filler volume fraction since the nanocomposites are utilized in a wide range of high dielectric permittivity electronic components.

  11. Densification and microstructure of lead zirconate titanate ceramics fabricated from a triol sol–gel powder

    Microsoft Academic Search

    C. Sangsubun; A. Watcharapasorn; S. Jiansirisomboon

    2008-01-01

    Lead zirconate titanate (PZT) nano-powder was prepared by a triol sol–gel process. X-ray diffraction and transmission electron microscopy results showed that as-synthesized amorphous powder started to crystallize at the calcination temperature above 500°C. The crystalline powder was formed into pellets and sintered at temperatures between 900 and 1300°C. Co-existence of tetragonal and rhombohedral phase was observed in all ceramics. Microstructural

  12. Fabrication of Lead Zirconate Titanate Thick Films Using a Powder Containing Organic Residue

    Microsoft Academic Search

    Byung-Dong Hahn; Ki-Hun Kim; Dong-Soo Park; Jong-Jin Choi; Jungho Ryu; Woon-Ha Yoon; Chan Park; Doh-Yeon Kim

    2008-01-01

    Crack-free, lead zirconate titanate (PZT) films with a thickness range of 20-100 mum were deposited on silicon substrate by aerosol deposition (AD) process using powders containing 1-12 wt % of organic species prepared by sol-gel route. The as-deposited films were annealed at 700 °C for 5 min by rapid thermal annealing (RTA) to improve the electrical properties. No delaminations or

  13. Surface Plasmon Resonance in Novel Nanocomposite Gold\\/Lead Zirconate Titanate Films Prepared by Aerosol Deposition Method

    Microsoft Academic Search

    Jae-Hyuk Park; Jun Akedo; Masafumi Nakada

    2006-01-01

    We prepared gold\\/lead zirconate titanate (PZT) nanocomposite thick films by the aerosol deposition method (ADM) for the first time and report their enhanced surface plasmon resonance (SPR) properties. ADM has been attracting much attention for its ability to deposit complex composite films at a high deposition rate and a low process temperature. Composite metal-dielectric powders are prepared from submicron particles

  14. Characterization of lead zirconate titanate--lanthanum ruthenate thin film structures prepared by chemical solution deposition.

    PubMed

    Bencan, Andreja; Malic, Barbara; Drazic, Goran; Vukadinovi?, Miso; Kosec, Marija

    2007-01-01

    In this work, the results of compositional and microstructural analysis of lead zirconate titanate--lanthanum ruthenate thin film structures prepared by chemical solution deposition are discussed. The cross-section transmission electron microscope (TEM) micrographs of the La-Ru-O film deposited on a SiO2/Si substrate and annealed at 700 degrees C revealed RuO2 crystals embedded in a glassy silicate matrix. When the La-Ru-O film was deposited on a Pt/TiO2/SiO2/Si substrate, RuO2 and La4Ru6O19 crystallized after annealing at 700 degrees C. After firing at 550 degrees C randomly oriented lead zirconate titanate (PZT) thin films crystallized on the La-Ru-O/SiO2/Si substrate, while on La-Ru-O/Pt/TiO2/SiO2/Si substrates PZT thin films with (111) preferred orientation were obtained. No diffusion of the Ru atoms in the PZT film was found. Ferroelectric response of PZT thin films on these substrates is shown in comparison with the PZT film deposited directly on the Pt/TiO2/SiO2/Si substrate without a La-Ru-O layer. PMID:18076056

  15. Nanoshell tubes of ferroelectric lead zirconate titanate and barium titanate Yun Luo, Izabela Szafraniak, and Nikolai D. Zakharov

    E-print Network

    Ramesh, R.

    Nanoshell tubes of ferroelectric lead zirconate titanate and barium titanate Yun Luo, Izabela templates, barium titanate and lead zirconate titanate tubes with diameters ranging from 50 nm up to several force of the process leads to reduction of the surface energy of the system.19 Lead zirconate titanate

  16. Optimization of PZT processing using thermal ink-jet printing

    E-print Network

    Jeon, Jessie Sungyun

    2008-01-01

    Lead zirconate titanate (PZT) has been known for its strong piezoelectric property for micro-sensors and actuators. Yet, its use in MEMS has been constrained by limitations in processing PZT with current MEMS fabrication ...

  17. Ink jet printing of PZT thin films for MEMS

    E-print Network

    Bathurst, Stephen, 1980-

    2012-01-01

    Of the readily available piezoelectric engineering materials perovskite phase lead zirconate titanate (PZT) has the strongest mechanical to electrical coupling. PZT based devices have the potential to have the highest ...

  18. Pyroelectric response of lead zirconate titanate thin films on silicon: Effect of thermal stresses

    SciTech Connect

    Kesim, M. T.; Zhang, J.; Alpay, S. P. [Department of Materials Science and Engineering and Institute of Materials Science, University of Connecticut, Storrs, Connecticut 06269 (United States); Trolier-McKinstry, S. [Department of Materials Science and Engineering and Materials Research Institute, Pennsylvania State University, Pennsylvania 16802 (United States); Mantese, J. V. [United Technologies Research Center, East Hartford, Connecticut 06118 (United States); Whatmore, R. W. [Tyndall National Institute, Lee Maltings, Dyke Parade, Cork City, County Cork (Ireland)

    2013-11-28

    Ferroelectric lead zirconate titanate [Pb(Zr{sub x}Ti{sub 1-x}O){sub 3}, (PZT x:1-x)] has received considerable interest for applications related to uncooled infrared devices due to its large pyroelectric figures of merit near room temperature, and the fact that such devices are inherently ac coupled, allowing for simplified image post processing. For ferroelectric films made by industry-standard deposition techniques, stresses develop in the PZT layer upon cooling from the processing/growth temperature due to thermal mismatch between the film and the substrate. In this study, we use a non-linear thermodynamic model to investigate the pyroelectric properties of polycrystalline PZT thin films for five different compositions (PZT 40:60, PZT 30:70, PZT 20:80, PZT 10:90, PZT 0:100) on silicon as a function of processing temperature (25–800?°C). It is shown that the in-plane thermal stresses in PZT thin films alter the out-of-plane polarization and the ferroelectric phase transformation temperature, with profound effect on the pyroelectric properties. PZT 30:70 is found to have the largest pyroelectric coefficient (0.042??C cm{sup ?2}?°C{sup ?1}, comparable to bulk values) at a growth temperature of 550?°C; typical to what is currently used for many deposition processes. Our results indicate that it is possible to optimize the pyroelectric response of PZT thin films by adjusting the Ti composition and the processing temperature, thereby, enabling the tailoring of material properties for optimization relative to a specific deposition process.

  19. Effect of surface modification of lead zirconate titanate particles on the properties of piezoelectric composite sensors

    NASA Astrophysics Data System (ADS)

    Saber, Nasser; Ma, Jun; Hsu, Hung-Yao; Lee, Sang-Heon; Marney, Donavan

    2013-08-01

    Piezoelectric composite sensors which consist of a ferroelectric ceramic phase and a polymer binder have been the center of interest for offering a distributed sensing mechanism in many industrial applications. This study investigates the effect of PZT surface modification on the mechanical and piezoelectric properties of PZT/epoxy composite sensors. Lead zirconate titanate ceramic powder (PZT-5H) was surface modified to prepare a high PZT content (0-3) piezoelectric composite sensor. Functional groups of the modifiers grafted onto the PZT particle surface served as a bridge into the epoxy matrix, thus creating strong bonds between the matrix and PZT particles. This noticeably improved the dispersion of the PZT phase, allowing the use of large fractions of piezoactive component in the composite. It is demonstrated that the produced piezo-film shows an enhanced poling behavior in that it can be poled with lower voltages under reduced poling times. This is caused by greater levels of microstructural homogeneity in the modified films as well as alteration of interfacial charge characteristics using modifiers' functional groups.

  20. Dielectric hysteresis from transverse electric fields in lead zirconate titanate thin films

    NASA Astrophysics Data System (ADS)

    Xu, Baomin; Ye, Yaohong; Cross, L. Eric; Bernstein, Jonathan J.; Miller, Raanan

    1999-06-01

    Excellent symmetric dielectric hysteresis is observed from lead zirconate titanate (PZT) thin films using transverse electric fields driven by interdigitated surface electrodes. The 1-?m-thick PZT films with a Zr/Ti ratio of 52/48 are prepared on ZrO2 buffered, 4-in.-diam silicon wafers with a thermally grown SiO2 layer. Both the ZrO2 buffer layer and PZT film are deposited by using a similar sol-gel processing. Remanent polarization of about 20 ?C/cm2 with coercive field less than 40 kV/cm is obtained as measured using a triangle wave at 50 Hz. Thicker films are being developed and retention for the transversely polarized state is currently under study. One of the objectives of this study is to develop a large array of d33-driven unimorph sensing elements for a high-resolution acoustic imaging system.

  1. Detection of water-ice transition using a lead zirconate titanatebrass Xiaoping Li and Wan Y. Shiha)

    E-print Network

    Aksay, Ilhan A.

    Detection of water-ice transition using a lead zirconate titanateÕbrass transducer Xiaoping Li the resonance frequency of a lead zirconate titanate PZT /brass unimorph disk transducer with a water ice layer

  2. Study of impedance parameters of cerium modified lead zirconate titanate ceramics

    Microsoft Academic Search

    Balgovind Tiwari; R. N. P. Choudhary

    2010-01-01

    A high-temperature solid-state reaction technique was used to prepare the polycrystalline samples of cerium (Ce) modified lead zirconate titanate with Zr\\/Ti ratio 65:35 (i.e., Pb(Zr0.65-xCexTi0.35)O3 (PZCT)). Preliminary X-ray structural analysis exhibits the formation of the new compositions of PZT. In order to study the compositional effects on the electrical properties (complex impedance Z*, complex modulus M*, electrical conductivity and relaxation

  3. Hydrogen diffusion in Lead Zirconate Titanate and Barium Titanate

    SciTech Connect

    Alvine, Kyle J.; Vijayakumar, M.; Bowden, Mark E.; Schemer-Kohrn, Alan L.; Pitman, Stan G.

    2012-08-28

    Hydrogen is a potential clean-burning, next-generation fuel for vehicle and stationary power. Unfortunately, hydrogen is also well known to have serious materials compatibility issues in metals, polymers, and ceramics. Piezoelectric actuator materials proposed for low-cost, high efficiency high-pressure hydrogen internal combustion engines (HICE) are known to degrade rapidly in hydrogen. This limits their potential use and poses challenges for HICE. Hydrogen-induced degradation of piezoelectrics is also an issue for low-pressure hydrogen passivation in ferroelectric random access memory. Currently, there is a lack of data in the literature on hydrogen species diffusion in piezoelectrics in the temperature range appropriate for the HICE as charged via a gaseous route. We present 1HNMR quantification of the local hydrogen species diffusion within lead zirconate titanate and barium titanate on samples charged by exposure to high-pressure gaseous hydrogen ?32?MPa. Results are discussed in context of theoretically predicted interstitial hydrogen lattice sites and aqueous charging experiments from existing literature.

  4. Piezoelectric Properties of Polycrystalline Lead Titanate Zirconate Compositions

    Microsoft Academic Search

    D. A. Berlincourt; C. Cmolik; H. Jaffe

    1960-01-01

    Detailed data are given for the piezoelectric, elastic, and dielectric properties of lead titanate zirconate ceramic compositions near the rhombohedral-tetragonal phase boundary. These compositions have markedly higher electromechanical coupling factors, remanent ferroelectric charge, and coercive field, than ceramic barium titanate. Another interesting feature is a pronounced change in the free permittivity ¿33T by the poling process; this change is in

  5. Fracture mechanisms in ferroelectric-ferroelastic lead zirconate titanate (Zr:Ti = 0. 54:0. 46) ceramics

    Microsoft Academic Search

    Karun Mehta; Anil V. Virkar

    1990-01-01

    Fracture toughness, {ital K}{sub IC}, of a single-phase commercial lead zirconate titanate (PZT) ceramic of tetragonal structure was measured using the single edge notched beam method above and below the Curie temperature. Domain switching (poling) under electrical and mechanical loading was examined using x-ray diffraction. Surface grinding, electrical poling, and mechanical poling caused crystallographic texture. Similar texture, indicative of domain

  6. Effect of polarization fatigue on the Rayleigh coefficients of ferroelectric lead zirconate titanate thin films: Experimental evidence and implications

    NASA Astrophysics Data System (ADS)

    Lou, X. J.; Zhang, H. J.; Luo, Z. D.; Zhang, F. P.; Liu, Y.; Liu, Q. D.; Fang, A. P.; Dkhil, B.; Zhang, M.; Ren, X. B.; He, H. L.

    2014-09-01

    The effect of polarization fatigue on the Rayleigh coefficients of ferroelectric lead zirconate titanate (PZT) thin film was systematically investigated. It was found that electrical fatigue strongly affects the Rayleigh behaviour of the PZT film. Both the reversible and irreversible Rayleigh coefficients decrease with increasing the number of switching cycles. This phenomenon is attributed to the growth of an interfacial degraded layer between the electrode and the film during electrical cycling. The methodology used in this work could serve as an alternative way for evaluating the fatigue endurance and degradation in dielectric properties of ferroelectric thin-film devices during applications.

  7. Surface Plasmon Resonance in Novel Nanocomposite Gold/Lead Zirconate Titanate Films Prepared by Aerosol Deposition Method

    NASA Astrophysics Data System (ADS)

    Park, Jae-Hyuk; Akedo, Jun; Nakada, Masafumi

    2006-09-01

    We prepared gold/lead zirconate titanate (PZT) nanocomposite thick films by the aerosol deposition method (ADM) for the first time and report their enhanced surface plasmon resonance (SPR) properties. ADM has been attracting much attention for its ability to deposit complex composite films at a high deposition rate and a low process temperature. Composite metal-dielectric powders are prepared from submicron particles of PZT and nano particles of gold (10-40 nm) with concentrations below 1 wt %. Nanocomposite gold/PZT 3-?m-thick film acquired enhanced SPR at approximately 640 nm as a result of annealing. The SPR position in nanocomposite films deposited by ADM can be precisely controlled by adjusting the dielectric constant of the host matrix by annealing. Moreover, nanogold particles were spatially very well distributed in the PZT matrix and showed no growth in spite of annealing at 600 °C.

  8. Fatigue of extracted lead zirconate titanate multilayer actuators under unipolar high field electric cycling

    SciTech Connect

    Wang, Hong [ORNL; Lee, Sung Min [ORNL; Wang, James L [ORNL; Lin, Hua-Tay [ORNL

    2014-01-01

    Testing of large prototype lead zirconate titanate (PZT) stacks presents substantial technical challenges to electronic testing systems, so an alternative approach that uses subunits extracted from prototypes has been pursued. Extracted 10-layer and 20-layer plate specimens were subjected to an electric cycle test under an electric field of 3.0/0.0 kV/mm, 100 Hz to 10^8 cycles. The effects of measurement field level and stack size (number of PZT layers) on the fatigue responses of piezoelectric and dielectric coefficients were observed. On-line monitoring permitted examination of the fatigue response of the PZT stacks. The fatigue rate (based on on-line monitoring) and the fatigue index (based on the conductance spectrum from impedance measurement or small signal measurement) were developed to quantify the fatigue status of the PZT stacks. The controlling fatigue mechanism was analyzed against the fatigue observations. The data presented can serve as input to design optimization of PZT stacks and to operation optimization in critical applications such as piezoelectric fuel injectors in heavy-duty diesel engines.

  9. Effect of compositional inhomogeneity on the structure and properties of lead zirconate titanate ferroelectric ceramics

    SciTech Connect

    Bogosova, Y.B.; Konstantinov, G.M. [Rostov State Univ. (Russian Federation)

    1995-04-01

    Lead zirconate titanate (PZT) ferroelectric ceramics are most generally produced from oxides by the solid-state-reaction method. The synthesis stage, as a rule, does not yield highly homogeneous solid solutions. Because of incomplete mixing of the starting reagents, the forming solid-solution material contains fairly large regions that differ in composition and, hence, in lattice parameters and physical properties. Homogenization of the solid solution is achieved at the sintering stage. Solid solutions whose compositions fall within morphotropic-transition regions (MTRs) are particularly sensitive to the preparation conditions used in producing ferroelectric ceramics because, for these solid solutions, even minor local changes in the concentration of components may have a considerable effect on phase composition, lattice parameters, and, hence, physical properties. The objective of this work was to study the effect of the homogeneity changes caused by sintering on the structure and properties of PZT ferroelectric ceramics.

  10. Thickness dependence of structural and electrical properties in epitaxial lead zirconate titanate films

    E-print Network

    Alpay, S. Pamir

    Thickness dependence of structural and electrical properties in epitaxial lead zirconate titanate of misfit strain on the microstructure and properties of ferroelectric lead zirconate titanate thin films and subsequently control it. The earliest studies on the switching behavior of lead zirconate titanate thin films

  11. The development of lead zirconate titanate thin films for piezoelectric microactuators

    NASA Astrophysics Data System (ADS)

    Nickles, Annabel Susan

    Piezoelectric actuation of a thin film is one means used for electrical-mechanical transduction in Microelectromechanical systems (MEMS). Currently, the most commonly employed piezoelectric thin-film material is ZnO. Replacing ZnO with certain compositions of lead zirconate titanate (PZT) should improve the performance of many MEMS devices due to the significantly greater piezoelectric coefficients of PZT (˜20 times greater than ZnO). In this dissertation I investigate the growth and properties---particularly piezoelectric properties---of PZT thin films. I also fabricate a PZT-based MEMS structure, a flexural plate wave (FPW) pump, and compare its performance with similar ZnO-based devices. PZT films of two compositions, Pb(Zr0.7Ti0.3)O 3 and Pb(Zr0.5Ti0.5)O3, were grown using reactive, multi-target, RF-magnetron sputtering on Pt-coated silicon wafers. Films were deposited at temperatures from 200°C to 400°C and rapid thermally annealed between 450°C and 700°C to crystallize perovskite PZT. The effects of as-deposited lead excess and deficiency on perovskite phase formation and film properties were studied. Films of composition Pb(Zr 0.5Ti0.5)O3, with relative dielectric constants of 1000, remanent polarizations of 20°C/cm2, coercive fields of 60 kV/cm, and effective piezoelectric d33 coefficients of 50 pm/V were obtained. These films show promise for use in MEMS. PZT films also were grown on a series of substrates using pulsed laser deposition (PLD). Epitaxial (100) films were obtained on LaAlO3 single crystal substrates, and randomly oriented films were obtained on Pt-coated silicon wafers. A conducting oxide electrode, (La0.5Sr0.5 )CoO3, was used for these films. Good structural and ferroelectric properties were obtained, however these films have limitations for use in MEMS. An FPW pump was fabricated using a sol-gel PZT thin film. Measured wave amplitudes were significantly higher than those of a similar ZnO-based device at the same driving voltage---250 A on a 5-finger pair PZT device as compared to 145 A on a 25-finger pair ZnO device. Estimations of pumping speed indicate that the PZT device should have a pumping speed more than an order of magnitude greater than the ZnO device.

  12. Transverse piezoelectric coefficient measurement of flexible lead zirconate titanate thin films

    NASA Astrophysics Data System (ADS)

    Dufay, T.; Guiffard, B.; Thomas, J.-C.; Seveno, R.

    2015-05-01

    Highly flexible lead zirconate titanate, Pb(Zr,Ti)O3 (PZT), thin films have been realized by modified sol-gel process. The transverse piezoelectric coefficient d31 was determined from the tip displacement of bending-mode actuators made of PZT cantilever deposited onto bare or RuO2 coated aluminium substrate (16 ?m thick). The influence of the thickness of ruthenium dioxide RuO2 and PZT layers was investigated for Pb(Zr0.57Ti0.43)O3. The modification of Zr/Ti ratio from 40/60 to 60/40 was done for 3 ?m thick PZT thin films onto aluminium (Al) and Al/RuO2 substrates. A laser vibrometer was used to measure the beam displacement under controlled electric field. The experimental results were fitted in order to find the piezoelectric coefficient. Very large tip deflections of about 1 mm under low voltage (˜8 V) were measured for every cantilevers at the resonance frequency (˜180 Hz). For a given Zr/Ti ratio of 58/42, it was found that the addition of a 40 nm thick RuO2 interfacial layer between the aluminium substrate and the PZT layer induces a remarkable increase of the d31 coefficient by a factor of 2.7, thus corresponding to a maximal d31 value of 33 pC/N. These results make the recently developed PZT/Al thin films very attractive for both low frequency bending mode actuating applications and vibrating energy harvesting.

  13. Interactions between lead-zirconate titanate, polyacrylic acid, and polyvinyl butyral in ethanol and their influence on electrophoretic deposition behavior.

    PubMed

    Kuscer, Danjela; Bakari?, Tina; Kozlev?ar, Bojan; Kosec, Marija

    2013-02-14

    Electrophoretic deposition (EPD) is an attractive method for the fabrication of a few tens of micrometer-thick piezoelectric layers on complex-shape substrates that are used for manufacturing high-frequency transducers. Niobium-doped lead-zirconate titanate (PZT Nb) particles were stabilized in ethanol using poly(acrylic acid) (PAA). With Fourier-transform infrared spectroscopy (FT-IR), we found that the deprotonated carboxylic group from the PAA is coordinated with the metal in the perovskite PZT Nb structure, resulting in a stable ethanol-based suspension. The hydroxyl group from the polyvinyl butyral added into the suspension to prevent the formation of cracks in the as-deposited layer did not interact with the PAA-covered PZT Nb particles. PVB acts as a free polymer in ethanol-based suspensions. The electrophoretic deposition of micro- and nanometer-sized PZT Nb particles from ethanol-based suspensions onto electroded alumina substrates was attempted in order to obtain uniform, crack-free deposits. The interactions between the PZT Nb particles, the PAA, and the PVB in ethanol will be discussed and related to the properties of the suspensions, the deposition yield and the morphology of the as-deposited PZT Nb thick film. PMID:23025567

  14. Electrical fatigue behaviour in lead zirconate titanate: an experimental and theoretical study

    NASA Astrophysics Data System (ADS)

    Bhattacharyya, Mainak; Arockiarajan, A.

    2013-08-01

    A systematic investigation on electrical fatigue in lead zirconate titanate (PZT) is carried out for different loading frequencies. Experiments are conducted up to 106 cycles to measure the electrical displacement and longitudinal strain on bulk ceramics in the bipolar mode with large electrical loading conditions. A simplified macroscopic model based on physical mechanisms of domain switching is developed to predict the non-linear behaviour. In this model, the volume fraction of a domain is used as the internal variable by considering the mechanisms of domain nucleation and propagation (domain wall movement). The measured material properties at different fatigue cycles are incorporated into the switching model as damage parameters and the classical strain versus electric field and electric displacement versus electric field curves are simulated. Comparison between the experiments and simulations shows that the proposed model can reproduce the characteristics of non-linear as well as fatigue responses.

  15. Piezoelectric and dielectric performance of poled lead zirconate titanate subjected to electric cyclic fatigue

    NASA Astrophysics Data System (ADS)

    Wang, Hong; Matsunaga, Tadashi; Lin, Hua-Tay; Mottern, Alexander M.

    2012-02-01

    Poled lead zirconate titanate (PZT) material as a single-layer plate was tested using a piezodilatometer under electric cyclic loading in both unipolar and bipolar modes. Its responses were evaluated using unipolar and bipolar measurements on the same setup. The mechanical strain and charge density loops exhibited various variations when the material was cycled for more than 108 cycles. The various quantities including loop amplitude, hysteresis, switchable polarization, and coercive field were characterized accordingly under the corresponding measurement conditions. At the same time, the offset polarization and bias electric field of the material were observed to be changed and the trend was found to be related to the measurement conditions also. Finally, the piezoelectric and dielectric coefficients were analyzed and their implications for the application of interest have been discussed.

  16. Improved dielectric properties of lead zirconate titanate thin films deposited on metal foils with LaNiO3 buffer layers

    Microsoft Academic Search

    Q. Zou; H. E. Ruda; B. G. Yacobi

    2001-01-01

    Improved dielectric properties of lead zirconate titanate (PZT) films deposited on a variety of foils using buffer layers are reported. Foils include titanium, stainless steel, and nickel with LaNiO3(LNO) buffer layers which were prepared by sol-gel processing. High dielectric constant (330 for stainless steel, 420 for titanium, and 450 for nickel foils), low dielectric loss (<2.2% for titanium and 8%

  17. In situ, in-liquid, all-electrical detection of Salmonella typhimurium using lead titanate zirconate\\/gold-coated glass cantilevers at any dipping depth

    Microsoft Academic Search

    Qing Zhu; Wan Y. Shih; Wei-Heng Shih

    2007-01-01

    Most biosensing techniques are indirect, slow, and require labeling. Even though silicon-based microcantilever sensors are sensitive and label-free, they are not suitable for in-liquid detection. More recently lead zirconate titanate (PZT) thin-film-based microcantilevers are shown to be sensitive and in situ. However, they require microfabrication and must be electrically insulated. In this study, we show that highly sensitive, in situ,

  18. Fatigue and failure responses of lead zirconate titanate multilayer actuator under unipolar high-field electric cycling

    NASA Astrophysics Data System (ADS)

    Zeng, Fan Wen; Wang, Hong; Lin, Hua-Tay

    2013-07-01

    Lead zirconate titanate (PZT) multilayer actuators with an interdigital electrode design were studied under high electric fields (3 and 6 kV/mm) in a unipolar cycling mode. A 100 Hz sine wave was used in cycling. Five specimens tested under 6 kV/mm failed from 3.8 × 105 to 7 × 105 cycles, whereas three other specimens tested under 3 kV/mm were found to be still functional after 108 cycles. Variations in piezoelectric and dielectric responses of the tested specimens were observed during the fatigue test, depending on the measuring and cycling conditions. Selected fatigued and damaged actuators were characterized using an impedance analyzer or small signal measurement. Furthermore, involved fatigue and failure mechanisms were investigated using scanning acoustic microscope and scanning electron microscope. The extensive cracks and porous regions were revealed across the PZT layers on the cross sections of a failed actuator. The results from this study have demonstrated that the high-field cycling can accelerate the fatigue of PZT stacks as long as the partial discharge is controlled. The small signal measurement can also be integrated into the large signal measurement to characterize the fatigue response of PZT stacks in a more comprehensive basis. The former can further serve as an experimental method to test and monitor the behavior of PZT stacks.

  19. Mechanical Reinforcement and Piezoelectric Properties of PZT Ceramics Embedded with NanoCrystalline

    Microsoft Academic Search

    Da-Wei Wang; Hai-Bo Jin; Jie Yuan; Bao-Li Wen; Quan-Liang Zhao; De-Qing Zhang; Mao-Sheng Cao

    2010-01-01

    The double-scale lead zirconate titanate (PZT) piezoelectric ceramics were prepared by the solid state processing with PZT nano-crystalline and micro-powder. The microstructures, electrical and mechanical properties of the double-scale PZT are investigated. All the sintered ceramics exhibit a single perovskite structure and the grain size of the double-scale PZT reduces due to the incorporation of PZT nano-crystalline. Compared to normal

  20. Patterned growth of Au nanoparticles on polycrystalline lead zirconate titanate surfaces.

    PubMed

    Kim, Jung Hun; Kwon, Sangwoo; Yang, Woochul

    2014-10-01

    We report the patterned growth of Au nanoparticles (NPs) on polarity-patterned polycrystalline lead zirconate titanate (PZT) as a template through photochemical reaction. The photochemical deposition of the Au NPs includes ultraviolet (UV) light illumination of the patterned PZT while immersed in a HAuCl4 solution. In particular, the influence of the UV wavelength, and the influence of the solution with the stabilizer and reducer on the growth selectivity of the Au NPs on the polarity-patterned regions was investigated. For a UV light of 365 nm wavelength, corresponding to a band-gap excitation of the PZT, more Au NPs were deposited on the + z polar region than on the other non-polar regions. However, no deposition of the Au NPs was observed for UV light wave-lengths longer than - 365 nm. When ascorbic acid (AA) as a reducer and cetyl-trimethylammonium bromide (CTAB) as a stabilizer were added to the HAuCl4 solution, the Au NPs on the + z polar region were observed to be deposited with a UV light of 435 nm, which is larger than the optical band gap wavelength of the PZT. Also, the growth selectivity and size uniformity on the + z region was significantly improved. These results could be due to the defect-induced photo-excitation of electrons and enhanced reduction process of Au+ ions by adding the reducer and the stabilizer in the photo-chemical process. This study suggests the possibility of the patterned growth of Au NPs on a ferroelectric surface through polarity patterning and photochemical reaction by optimizing the UV wavelength and employing reduction potential agents in a metal salt solution. PMID:25942907

  1. Design of MEMS PZT circular diaphragm actuators to generate large deflections

    Microsoft Academic Search

    Eunki Hong; Susan Trolier-McKinstry; Robert L. Smith; Silai V. Krishnaswamy; Carl B. Freidhoff

    2006-01-01

    This paper presents a design of lead zirconate titanate (PZT) circular diaphragm actuators to generate large deflections. The actuators utilize a unimorph structure consisting of an active PZT and a passive thermally grown SiO2 layer. The diaphragm structures were formed by deep reactive ion etching (DRIE). Two different designs, where the PZT layer in the diaphragm actuators was driven by

  2. A circular array transducer for photoacoustic imaging by using piezoelectric single crystal lead magnesium niobate–lead zirconate titanate

    NASA Astrophysics Data System (ADS)

    Cao, Yonggang; Ha, Kanglyeol; Kim, Moojoon; Kang, Hyunwook; Oh, Jung-Hwan; Kim, Jungsoon

    2015-07-01

    The ultrasound transducers of which center frequencies are lower than 10 MHz are commonly used in low frequency photoacoustic (PA) imaging systems. However, the improvement of their sensitivity is still needed to detect weak PA signals. In this study, a circular array transducer was constructed by using 120 needle hydrophones made of piezoelectric single crystal lead magnesium niobate–lead zirconate titanate (PMN–PZT). The needle hydrophone was designed to have high sensitivity and wide bandwidth through the Krimtholz–Leedom–Matthaei (KLM) simulation of receiving impulse response. The sensitivity of the fabricated PMN–PZT hydrophone was compared with a commercial poly(vinylidene fluoride) (PVDF) needle hydrophone. The usefulness of the circular array transducer was demonstrated by applying it to a PA system for obtaining images.

  3. Received 8 Mar 2014 | Accepted 24 Jun 2014 | Published 5 Aug 2014 Conformable amplified lead zirconate titanate

    E-print Network

    Rogers, John A.

    lead zirconate titanate sensors with enhanced piezoelectric response for cutaneous pressure monitoring studies reveal enhanced piezoelectric responses in lead zirconate titanate that follow from integration co-integration of other types of active materials and classes of components. Lead zirconate titanate

  4. Strontium doped lead zirconate titanate ceramics: study of calcination and sintering process to improve piezo effect.

    PubMed

    Khalid, Muhammad; Shoaib, Muhammad; Khan, Amir Azam

    2011-06-01

    Perovskite crystal structure is found in many ionic solids like CaTiO3, BaTiO3 and Lead Zirconate Titanates (PZT). In this structure off-center position of cations in oxygen octahedral causes polarization and produces direct and indirect piezoelectric responses in ceramic materials that are suitable for many ultrasonic applications. In the present study 9% Sr doped PZT ceramics were prepared and their dielectric and piezoelectric properties measured. X ray Diffraction (XRD) analysis of calcined powders demonstrated a decrease in the PbO content during the calcination stage at 850 degrees C. This was counterbalanced by adding excess PbO at the time of preparation of mixtures. Sintering was carried out at 1200 degrees C for 2 hours in lead rich atmosphere. The properties achieved were Dielectric Constant (K) = 1440, Tangent Loss (Tan delta) = 0.0062, Charge Coefficient (d33) = 335 pC/N and density = 7.55 g/cm3. SEM analysis of sintered samples demonstrated that grain size was 2-3 microm with clean grain boundaries and no large size porosity observed. XRD analysis of sintered pellets exhibited that material prepared was free of any precipitated phase usually harmful for the piezo effect. PMID:21770202

  5. Design and modeling of a PZT thin film based piezoelectric micromachined ultrasonic transducer (PMUT)

    E-print Network

    Smyth, Katherine Marie

    2012-01-01

    The design and modelling framework for a piezoelectric micromachined ultrasonic transducer (PMUT) based on the piezoelectric thin film deposition of lead zirconate titanate (PZT) is defined. Through high frequency vibration ...

  6. Mechanical Reinforcement and Piezoelectric Properties of PZT Ceramics Embedded with Nano-Crystalline

    NASA Astrophysics Data System (ADS)

    Wang, Da-Wei; Jin, Hai-Bo; Yuan, Jie; Wen, Bao-Li; Zhao, Quan-Liang; Zhang, De-Qing; Cao, Mao-Sheng

    2010-04-01

    The double-scale lead zirconate titanate (PZT) piezoelectric ceramics were prepared by the solid state processing with PZT nano-crystalline and micro-powder. The microstructures, electrical and mechanical properties of the double-scale PZT are investigated. All the sintered ceramics exhibit a single perovskite structure and the grain size of the double-scale PZT reduces due to the incorporation of PZT nano-crystalline. Compared to normal PZT, the mechanical properties increase significantly and the piezoelectric properties decrease slightly. Mechanisms responsible for the reinforcement of the double-scale PZT are discussed.

  7. Local origin of macroscopic properties and patterning in Lead zirconate titanate films

    NASA Astrophysics Data System (ADS)

    Bintachitt, Patamas

    This thesis describes the preparation of high quality lead zirconate titanate (PZT) films, the nonlinearity in their dielectric and piezoelectric responses, as well as their patterning by reactive ion etching. One goal of the research was to obtain {001} oriented PZT films on Pt-coated Si substrates. In this work, PbTiO3 buffer layers were chosen due to good lattice matching with PZT films, and the strong propensity for development of {001} orientation. The pyrolysis, crystallization steps, and lead excess addition of PbTiO3 buffer layers deposition were investigated. Using a thin PbTiO3 buffer layer and controlled pyrolysis conditions allowed {100} oriented PZT films to be prepared. The PbTiO3 buffer layer can be used over a full wafer to provide orientation. Higher piezoelectric coefficients, e31,f of -14 and -10 C/m2 were achieved for {001} PZT thin films of 1.0 mum and 0.24 mum thickness, respectively using appropriate poling conditions. The local and global domain wall contributions were studied by piezoelectric nonlinearity and dielectric nonlinearity in both {001}-textured PZT films and PZT films with mixed {001} and {111} orientation. It was found that films over the thickness range probed showed Rayleigh-like behavior. 4 mum thick films were nearly uniform in their Rayleigh coefficient, suggesting that any heterogeneities in the response developed at lateral length scales below the resolution of the PFM measurement. In contrast, thinner films showed significantly more patchiness in their response, so that fluctuations in behavior developed at a lateral length scale on the order of 0.6 to 2.5 micron. These variations did not appear to be correlated directly with the surface topology. Finally, it is hypothesized that the same population of domain wall contributes to the local and global nonlinearity. Nanoindentation measurements were conducted in an attempt to distinguish 180° and non-180° domain wall motion in these films. Non-180° domain walls can be moved by both electrical and mechanical fields. In contrast, 180° domain walls can be moved by electric fields, but not by uniform stresses. In PZT films with mixed {111} and {001} orientation, some ferroelastic wall motion took place during loading, at stress levels on the order of GPa. The reduced elastic modulus is much higher on the unloading curve. Thus, on unloading, it is believed that there is no contribution from mechanical softening associated with ferroelasticity. The global polarization switching in polycrystalline, {001}-textured films on Si, and {001}-films on SrRuO3/SrTiO3 was studied through first order reversal curves (FORC) in order to assess the Preisach distribution governing the switching behavior. Acquisition of multiple hysteresis loops allows polarization switching parameters including nucleation biases, coercive biases, and the amount of switchable response to be mapped in real space. SS-PFM was studied on both bare PZT film surfaces and in capacitor structures (metal/PZT film/metal). The capacitor structure shows the evolution of correlated switching of 102 - 10 3 grain clusters with well-defined imprint and nucleation biases. A transition from a regime where the domain wall motion is over a short range to the formation of clusters to complete switching is observed. The switchable polarization as a function of bias window allows the voltage dependence and spatial distribution of regions with reversible and irreversible wall motions to be mapped. The final chapter of experimental work describes the patterning of PZT films for MEMS. The ability to dry etch large depths of ferroelectric materials such as lead zirconate titanate is important in both microelectromechanical systems and in high frequency medical ultrasound transducers. Dense Pb(Zr 0.52Ti0.48)O3 films (?1 mum) were used to study the etching characteristics. The variation of the etch rate with gas flow rate, source power, substrate holder power, and operation pressure and the uniformity of etching were investigated. The maximum etch rate achieved was 0.31 mum/min. The electric

  8. X-ray and neutron scattering on disordered nanosize clusters: a case study of lead-zirconate-titanate solid solutions

    NASA Astrophysics Data System (ADS)

    Frantti, Johannes; Fujioka, Yukari

    2015-04-01

    Defects and defect models of solids are reviewed. A numerical method able to treat non-periodical solids possessing several simultaneous defect types is given for simulating scattering in nanosize clusters. The approach takes particle size, shape, and defects into account and isolates element specific signals. Examples illustrating how laboratory scale facilities can be used to extract crucial information about defects are given. As a case study a statistical approximation model for lead-zirconate-titanate (PZT) is introduced. PZT is a material possessing several defect types, including substitutional, displacement and surface defects. Spatial composition variation is taken into account by introducing a model in which the edge lengths of each cell depend on the distribution of Zr and Ti ions in the cluster. Spatially varying edge lengths and angles are referred to as microstrain. The Pb, Zr and Ti cation positions were adjusted by bond-valence sum (BVS) model to fullfil nominal valence requirement. The model is applied to compute the scattering from ellipsoid shaped PZT clusters and to simulate the structural changes as a function of average composition. Two-phase co-existence range, the so called morphotropic phase boundary (MPB) composition is given correctly. To make a comparison with commonly used x-ray and neutron diffraction data selected Bragg reflection intensities and line shapes were simulated. Examples of the effect of size and shape of the scattering clusters on diffraction patterns are given and the particle dimensions, computed through Scherrer equation, are compared with the exact cluster dimensions. Scattering from two types of 180 degree domains in spherical particles, one type assigned to Ti-rich PZT and the second to the MPB and Zr rich PZT, is computed. We show how the method can be used for modelling polarization reversal.

  9. Lead zirconate titanate-based thick films for high-frequency focused ultrasound transducers prepared by electrophoretic deposition.

    PubMed

    Abellard, André-Pierre; Kuscer, Danjela; Grégoire, Jean-Marc; Lethiecq, Marc; Malic, Barbara; Levassort, Franck

    2014-03-01

    An electrophoretic deposition (EPD) process with high deposition rate was used to fabricate a curved piezoelectric thick film devoted to high-frequency transducers for medical imaging. Niobium-doped lead zirconate titanate (PZTNb) powder was stabilized in ethanol to prepare a suspension with high zeta potential and low conductivity. A gold layer, pad-printed and fired on a curved porous PZT substrate, was used as the working electrode for the deposition of the PZTNb thick film. This substrate was chosen because it has the required properties (acoustic impedance and attenuation) to be used directly as a backing for the high-frequency transducer, leading to a simplified process for transducer assembly with this integrated structure. PZT-Nb thick films were also deposited by EPD on flat gold-coated alumina substrates as a reference. The thickness of the films was between 20 and 35 ?m, and their electromechanical performance was comparable to standard PZT bulk ceramics with a thickness coupling factor of 48%. For the curved thick film, the thickness coupling factor was slightly lower. The corresponding integrated structure was used to fabricate a transducer with a center frequency of 40 MHz and an f-number of 2.8. It was integrated into a realtime ultrasound scanner and used to image human forearm skin; the resulting images showed, for the first time, the efficacy of the EPD process for these imaging applications. PMID:24569258

  10. Comparison of lead zirconate titanate thin films for microelectromechanical energy harvester with interdigitated and parallel plate electrodes.

    PubMed

    Chidambaram, Nachiappan; Mazzalai, Andrea; Balma, Davide; Muralt, Paul

    2013-08-01

    Lead zirconate titanate (PZT) thin films on insulator- buffered silicon substrates with interdigitated electrodes (IDEs) have the potential to harvest more energy than parallel plate electrode (PPE) structures because the former exploit the longitudinal piezoelectric effect, which is about twice as high as the transverse piezoelectric effect used by PPE structures. In this work, both options are compared with respect to dielectric, ferroelectric, and piezoelectric properties, leakage currents, and figure of merit (FOM) for energy harvesting. The test samples were silicon beams with {100} PZT thin films in the case of the PPE geometry, and random PZT thin films for the IDE geometry. Both films were obtained by an identical sol-gel route. Almost the same dielectric constants were derived when the conformal mapping method was applied for the IDE capacitor to correct for the IDE geometry. The dielectric loss was smaller in the IDE case. The ferroelectric loops showed a higher saturation polarization, a higher coercive field, and less back-switching for the IDE case. The leakage current density of the IDE structure was measured to be about 4 orders of magnitude lower than that of the PPE structure. The best FOM of the IDE structures was 20% superior to that of the PPE structures while also having a voltage response that was ten times higher (12.9 mV/? strain). PMID:25004526

  11. Formation and properties of porous films of lead zirconate titanate

    NASA Astrophysics Data System (ADS)

    Seregin, D. S.; Vorotilov, K. A.; Sigov, A. S.; Zubkova, E. N.; Abdullaev, D. A.; Kotova, N. M.; Vishnevskiy, A. S.

    2015-03-01

    The processes of formation and the properties of porous ceramic lead zirconate titanate films have been considered. The porous structure formed by thermal destruction of polyvinylpyrrolidone (PVP) with the molecular weight 29000 makes it possible to increase the cracking-free film thickness (by a factor of approximately two for one deposition at 20 wt % PVP; in this case, the volume porosity is 33%). An increase in the porosity decreases the permittivity ?; at 20 wt % PVP, ? = 432-456 depending on the film thickness. These values are less than those in nonporous films by a factor of more than two. An increase in the porosity is accompanied by an increase in the remanent polarization in the films. However, the hysteresis loop shape changes in the region of saturation polarization.

  12. Ferroelectric/ferroelastic behavior and piezoelectric response of lead zirconate titanate thin films under nanoindentation

    SciTech Connect

    Koval, V.; Reece, M.J.; Bushby, A.J. [Department of Materials, Queen Mary University of London, Mile End Road, London, E1 4NS (United Kingdom)

    2005-04-01

    The electromechanical response of pure lead zirconate titanate (PZT) and Mn-doped PZT thin ferroelectric films under nanoindentation forces of up to 500 mN was investigated. The stress-induced current transients were measured as a function of the externally applied load on films of different thicknesses using a spherical WC-Co cermet indenter of 500 {mu}m nominal radius. It was found that the quasi-static current generated through the direct piezoelectric effect is superimposed with a contribution from irreversible domain processes during the loading/unloading cycle. The film thickness dependency of the electrical transients and an asymmetry of the current-force curves are attributed to the in-plane clamping stress in the films produced by a dissimilar substrate. Analysis of corresponding charge-force hysteresis loops revealed a significant role for the residual stress state on the polarization switching in thin films. By the application of an indentation force, a portion of Barkhausen jumps was empirically estimated to increase as a consequence of reduction of the clamping effect on domains. The Rayleigh hysteretic charge-force curves showed recovery of the charge released during the load-unload stress cycle. For the thicker 700 nm films, the total charge released during loading was fully recovered with weak hysteresis. In contrast, strong in-plane clamping stresses in the 70 nm thick films are suggested to be reponsible for incomplete recovery upon unloading. A considerable domain-wall contribution to the electromechanical response was demonstrated by an enhanced polarization state, which was shown by an increase of the effective piezoelectric coefficient d{sub eff} of about 35% of its initial value for the thin films at a maximum force of 500 mN.

  13. Vibration Characteristics of Piezoelectric Lead Zirconate Titanate by Fluid Flow in Intravascular Oxygenator

    NASA Astrophysics Data System (ADS)

    Kim, Gi?Beum; Hong, Chul?Un; Kwon, Tae?Kyu

    2006-04-01

    In this paper, we describe the enhancement in oxygen transfer rate in hollow-fiber-membrane (HFM) modules using a plumbum piezoelectric lead zirconate titanate (PZT) actuator and a piezoelectric poly vinylidene fluoride (PVDF) sensor. We developed a vibrating intravascular lung assist device (VIVLAD) for patients having chronic respiratory problems and performed experiments on hydrodynamic flow through a bundle of sinusoidal vibrating hollow fibers. These modules were used to provide some insight into how wall vibrations might enhance the performance of an intravascular lung assist device. The experimental design and procedure are then applied to the fabrication of a device used to assess the effectiveness of membrane vibrations. The test section was a cylindrical duct with an inner diameter of 30 mm. The flow rate was controlled by a pump and monitored by a built-in flowmeter. The vibration apparatus was composed of a piezovibrator, a function generator, and a power amplifier. The direction of vibration was radial to the fluid flow. Gas flow rates of up to 6 L/min through 120-cm-long hollow fibers were achieved by exciting the piezovibrator. The time and frequency responses of PVDF sensors were investigated through various frequencies in VIVLAD. In these devices, the flow of blood and the source of oxygen were separated by a semipermeable membrane that allows oxygen and carbon dioxide to diffuse into and out of the fluid, respectively. Results of the experiments have shown that a vibrating intravascular lung assist device performs effectively.

  14. Effect of manganese doping on the size effect of lead zirconate titanate thin films and the extrinsic nature of 'dead layers'.

    PubMed

    Lou, X J; Wang, J

    2010-02-10

    We have investigated the size effect in lead zirconate titanate (PZT) thin films with a range of manganese (Mn) doping concentrations. We found that the dynamic size effect in the conventional Pt/PZT/Pt thin-film capacitors could be systematically reduced and almost completely eliminated by increasing Mn doping concentration. The interfacial layer at the electrode-film interface appears to disappear almost entirely for the PZT films with ? 2% Mn doping levels, confirmed by the fits using the conventional 'in-series capacitor' model. Our work indicates that the dynamic size effect in ferroelectrics is extrinsic in nature, supporting the work by Saad et al. Other implications of our results have also been discussed. By comparing a variety of experimental studies in the literature we propose a scenario that the 'dead layer' between PZT (or barium strontium titanate, BST) and metal electrodes such as Pt and Au might have a defective pyrochlore/fluorite-like structure (possibly with a small portion of ferroelectric perovskite phase). This scenario is then generalized by including the effect of the grain-boundary dead layer on the collapse of the dielectric constant in thinner films. PMID:21386350

  15. Effect of lanthanum doping on the electrical properties of sol-gel derived ferroelectric lead-zirconate-titanate for ultra-large-scale integration dynamic random access memory applications

    Microsoft Academic Search

    C. Sudhama; J. Kim; J. Lee; V. Chikarmane; W. Shepherd; E. R. Myers

    1993-01-01

    Thin films of lead-zirconate-titanate [(PZT) PbZr{sub 0.5}Ti{sub 0.5})Oâ] possess demonstrably adequate charge storage densities and endurance to read\\/write cycling for ultra-large-scale integration dynamic random access memory (DRAM) applications. Lanthanum (donor) doping is expected to reduce the (p-type) conductivity to acceptable levels (<10⁻⁶ A\\/cm²). In this study, six thin films of 200 nm sol-gel derived lanthanum-doped PZT, with the [La]\\/([La] +

  16. A Study of Fatigue Effect in PZ\\/PZT Multilayered Thin Films Prepared by Sol-Gel Technique

    Microsoft Academic Search

    Byung-Moon Jin; Se-Hwan Bae; Kie-Beom Jeon; Ill-Won Kim

    2005-01-01

    Lead Zirconate (PZ) and Lead Zirconium Titanate (PZT 48\\/52) multi-layered thin films were prepared by sol-gel technique. Sets of films (each layer has a 500 Å thickness) made by one PZ after one PZT layer were deposited 3 times successively, so it contained 3 PZ layers and 3 PZT layers. PZT film that was deposited on the Pt electrode was

  17. Electrical and mechanical properties of PZT thin films prepared by hybrid process of sol-gel technique and laser ablation

    Microsoft Academic Search

    Lulu Zhang; Masaaki Ichiki; Zhanjie Wang; Ryutaro Maeda

    2002-01-01

    To prepare lead zirconate titanate (Pb(ZrxTi1-x)O3): PZT) thin films at a higher deposition rate and a lower substrate temperature, the PZT films were fabricated by a hybrid process of sol-gel technique and pulsed laser ablation deposition. First, one layer of PZT (about 0.12-0.14 mum) was coated on Si\\/SiO2\\/Ti\\/Pt substrate by sol-gel process. Then PZT film was deposited at a rate

  18. Fabrication and modeling of bismuth titanate-PZT ceramic transducers for high temperature applications

    NASA Astrophysics Data System (ADS)

    Reinhardt, B.; Searfass, C.; Cyphers, R.; Sinding, K.; Pheil, C.; Tittmann, B.

    2013-01-01

    Utilization of a spray-on deposition technique of ferroelectric bismuth titanate (Bi4Ti3O12) composites has a competitive advantage to standard ultrasonic transducers. These can conform to curved surfaces, can operate at high temperature (Curie-Weiss temperature 685 °C) and are mechanically well-coupled to a substrate. However, an issue with many high temperature transducers such as bismuth titanate ceramics is that they have relatively low transduction efficiency, i.e. d33 is about 12-14 pC/F in Bi4Ti3O12 versus 650 pC/F in PZT-5H. It is a common conception that high-temperature capability comes at the cost of electro-mechanical coupling. It will be shown that the high temperature capability of bismuth-titanate-PZT composite transducers using the spray-on deposition technique previously developed, improves the electro-mechanical coupling while maintaining the high temperature performance and mechanical coupling. This material could provide advantages in harsh environments where high signal-to-noise ratios are needed.

  19. Effect of porosity on dielectric properties and microstructure of porous PZT ceramics

    Microsoft Academic Search

    B. Praveen Kumar; H. H. Kumar; D. K. Kharat

    2006-01-01

    Porous piezoelectric materials are of great interest because of their high hydrostatic figure of merit and low sound velocity, which results in to low acoustic impedance and efficient coupling with medium. Porous lead zirconate titanate (PZT) ceramics with varying porosity was developed using polymethyl methacrylate by burnable plastic spheres (BURPS) process. The porous PZT ceramics were characterized for dielectric constant

  20. Effects of Composition and Diameter of PZT Transducers on Energy Harvesting

    Microsoft Academic Search

    N. Putthongchai; T. Kulworawanichpong; P. Laoratanakul; S. Srilomsak

    2010-01-01

    Energy harvesting from wasted energy is a brilliant idea suitable for the world energy crisis. Piezoelectric materials such as Lead Zirconate Titanate (PZT) can be used to transform unused mechanical energy to electrical energy that can be stored and used to power electrical devices. Four types of PZT transducer with three different diameters were investigated in this work. The results

  1. Lead lanthanum zirconate titanate ceramic thin films for energy storage.

    PubMed

    Tong, Sheng; Ma, Beihai; Narayanan, Manoj; Liu, Shanshan; Koritala, Rachel; Balachandran, Uthamalingam; Shi, Donglu

    2013-02-01

    An acetic-acid-based sol-gel method was used to deposit lead lanthanum zirconate titanate (PLZT, 8/52/48) thin films on either platinized silicon (Pt/Si) or nickel buffered by a lanthanum nickel oxide buffer layer (LNO/Ni). X-ray diffraction and scanning electron microscopy of the samples revealed that dense polycrystalline PLZT thin films formed without apparent defects or secondary phases. The dielectric breakdown strength was greater in PLZT thin films deposited on LNO/Ni compared with those on Pt/Si, leading to better energy storage. Finally, optimized dielectric properties were determined for a 3-?m-thick PLZT/LNO/Ni capacitor for energy storage purposes: DC dielectric breakdown strength of ?1.6 MV/cm (480 V), energy density of ?22 J/cc, energy storage efficiency of ?77%, and permittivity of ?1100. These values are very stable from room temperature to 150 °C, indicating that cost-effective, volumetrically efficient capacitors can be fabricated for high-power energy storage. PMID:23373765

  2. Pressure, temperature, and electric field dependence of phase transformations in niobium modified 95/5 lead zirconate titanate

    NASA Astrophysics Data System (ADS)

    Dong, Wen D.; Carlos Valadez, J.; Gallagher, John A.; Jo, Hwan R.; Sahul, Raffi; Hackenberger, Wes; Lynch, Christopher S.

    2015-06-01

    Ceramic niobium modified 95/5 lead zirconate-lead titanate (PZT) undergoes a pressure induced ferroelectric to antiferroelectric phase transformation accompanied by an elimination of polarization and a volume reduction. Electric field and temperature drive the reverse transformation from the antiferroelectric to ferroelectric phase. The phase transformation was monitored under pressure, temperature, and electric field loading. Pressures and temperatures were varied in discrete steps from 0 MPa to 500 MPa and 25 °C to 125 °C, respectively. Cyclic bipolar electric fields were applied with peak amplitudes of up to 6 MV m-1 at each pressure and temperature combination. The resulting electric displacement-electric field hysteresis loops were open "D" shaped at low pressure, characteristic of soft ferroelectric PZT. Just below the phase transformation pressure, the hysteresis loops took on an "S" shape, which split into a double hysteresis loop just above the phase transformation pressure. Far above the phase transformation pressure, when the applied electric field is insufficient to drive an antiferroelectric to ferroelectric phase transformation, the hysteresis loops collapse to linear dielectric behavior. Phase stability maps were generated from the experimental data at each of the temperature steps and used to form a three dimensional pressure-temperature-electric field phase diagram.

  3. Enhanced mechanical properties in Ag-particle-dispersed PZT piezoelectric composites for actuator applications

    Microsoft Academic Search

    H. L. Zhang; J.-F. Li; B.-P. Zhang; W. Jiang

    2008-01-01

    Functional ceramics naturally have inferior mechanical properties. This study shows that incorporating Ag into lead zirconate titanate (PZT) piezoelectric ceramics by co-firing in air at 1200°C is effective for mechanical property enhancement. The Ag addition has increased the fracture strength ?f from 69MPa for monolithic PZT to 129MPa for PZT–15% Ag composite, and increased the corresponding fracture toughness KIC from

  4. Piezoelectric, pyroelectric and dielectric properties of La and Sm-doped PZT ceramics

    Microsoft Academic Search

    C. Pramila; T. C. Goel; P. K. C. Pillai

    1993-01-01

    Pair-doped lead zirconate titanate (PZT) samples were prepared by introducing lanthanum (La) and samarium (Sm) into the PZT lattice. Three compositions of pair-doped PZT were prepared by a conventional method. The dielectric, piezoelectric and pyroelectric properties of these samples were studied and compared with that of PLZT(8\\/65\\/35) samples prepared under the same conditions. The piezoelectric and pyroelectric figures of merit

  5. Evaluation of antibacterial properties of Barium Zirconate Titanate (BZT) nanoparticle

    PubMed Central

    Mohseni, Simin; Aghayan, Mahdi; Ghorani-Azam, Adel; Behdani, Mohammad; Asoodeh, Ahmad

    2014-01-01

    So far, the antibacterial activity of some organic and inorganic compounds has been studied. Barium zirconate titanate [Ba(ZrxTi1-x)O3] (x = 0.05) nanoparticle is an example of inorganic materials. In vitro studies have provided evidence for the antibacterial activity of this nanoparticle. In the current study, the nano-powder was synthesized by sol-gel method. X-ray diffraction showed that the powder was single-phase and had a perovskite structure at the calcination temperature of 1000 °C. Antibacterial activity of the desired nanoparticle was assessed on two gram-positive (Staphylococcus aureus PTCC1431 and Micrococcus luteus PTCC1625) and two gram-negative (Escherichia coli HP101BA 7601c and clinically isolated Klebsiella pneumoniae) bacteria according to Radial Diffusion Assay (RDA). The results showed that the antibacterial activity of BZT nano-powder on both gram-positive and gram-negative bacteria was acceptable. The minimum inhibitory concentration of this nano-powder was determined. The results showed that MIC values for E. coli, K. pneumoniae, M. luteus and S. aureus were about 2.3 ?g/mL, 7.3 ?g/mL, 3 ?g/mL and 12 ?g/mL, respectively. Minimum bactericidal concentration (MBC) was also evaluated and showed that the growth of E. coli, K. pneumoniae, M. luteus and S. aureus could be decreased at 2.3, 14, 3 and 18 ?g/mL of BZT. Average log reduction in viable bacteria count in time-kill assay ranged between 6 Log10 cfu/mL to zero after 24 h of incubation with BZT nanoparticle. PMID:25763046

  6. Preparation of Lead Zirconate Titanate Thin Film by Hydrothermal Method

    Microsoft Academic Search

    Katsuhiko Shimomura; Takaaki Tsurumi; Yoko Ohba; Masaki Daimon

    1991-01-01

    A hydrothermal method for preparing thin films of crystalline PZT was developed by controlling the rates of nucleation and crystal growth. This method consisted of two steps of hydrothermal reaction. The first step (nucleation process) was that in which the TiO2 substrate reacted with the mixed solution of Pb and Zr to form PZT and\\/or PZ nuclei on the surface.

  7. Surface morphology and stress analysis of piezoelectric strontium-doped lead zirconate titanate thin films

    Microsoft Academic Search

    Sharath Sriram; Madhu Bhaskaran; Anthony S. Holland

    2007-01-01

    Strontium-doped lead zirconate titanate (PSZT) is a piezoelectric ceramic with relatively high values of piezoelectric coefficients. Perovskite oriented PSZT thin films are also reported to exhibit a variety of other properties including ferroelectricity and pyroelectricity. This paper reports on a study of the surface morphology and resulting stress of PSZT thin films, deposited under a variety of RF magnetron sputtering

  8. Crack tip 90 domain switching in tetragonal lanthanum-modified lead zirconate titanate under an

    E-print Network

    Zhu, Ting

    ) Lanthanum-modified lead zirconate titanate ferroelectric ceramics (Pb0.96La0.04)(Zr0.40Ti0.60)0.99O3 were. I. INTRODUCTION Perovskite-type ferroelectric ceramics have been used as sensors, actuators conditions. However, ferroelectric ceramics are brittle and they may degrade under com- bined electrical

  9. Electric-fieldtemperature phase diagram of the relaxor ferroelectric lanthanum-modified lead zirconate titanate

    E-print Network

    Bobnar, Vid

    ferroelectrics. S0163-1829 99 00233-7 I. INTRODUCTION Lanthanum-modified lead zirconate titanate ceramics Pb1 x than EC 5 kV/cm a long-range ferroelectric order is established in 9/65/35 PLZT ceramics. In particularElectric-field­temperature phase diagram of the relaxor ferroelectric lanthanum-modified lead

  10. Raman study of lead zirconate titanate under uniaxial stress

    SciTech Connect

    TALLANT, DAVID R.; SIMPSON, REGINA L.; GRAZIER, J. MARK; ZEUCH, DAVID H.; OLSON, WALTER R.; TUTTLE, BRUCE A.

    2000-04-01

    The authors used micro-Raman spectroscopy to monitor the ferroelectric (FE) to antiferroelectric (AFE) phase transition in PZT ceramic bars during the application of uniaxial stress. They designed and constructed a simple loading device, which can apply sufficient uniaxial force to transform reasonably large ceramic bars while being small enough to fit on the mechanical stage of the microscope used for Raman analysis. Raman spectra of individual grains in ceramic PZT bars were obtained as the stress on the bar was increased in increments. At the same time gauges attached to the PZT bar recorded axial and lateral strains induced by the applied stress. The Raman spectra were used to calculate an FE coordinate, which is related to the fraction of FE phase present. The authors present data showing changes in the FE coordinates of individual PZT grains and correlate these changes to stress-strain data, which plot the macroscopic evolution of the FE-to-AFE transformation. Their data indicates that the FE-to-AFE transformation does not occur simultaneously for all PZT grains but that grains react individually to local conditions.

  11. Preparation of Lead Zirconate Titanate (Pb(Zr0.52Ti0.48)O3) by Homogeneous Precipitation and Calcination

    E-print Network

    Tas, A. Cuneyt

    Preparation of Lead Zirconate Titanate (Pb(Zr0.52Ti0.48)O3) by Homogeneous Precipitation-ray spectroscopy (EDXS). I. Introduction LEAD ZIRCONATE TITANATE (PbZrxTi1-xO3) ceramics are of great technological by a semiwet procedure. In the present study, the experimental details of the synthesis of lead zirconate

  12. Influence of combined external stress and electric field on electric properties of 0.5% Fe-doped lead zirconate titanate ceramics

    NASA Astrophysics Data System (ADS)

    Suchanicz, J.; Kim-Ngan, N.-T. H.; Konieczny, K.; Jankowska-Sumara, I.; Sitko, D.; Goc-Jaglo, D.; Balogh, A. G.

    2009-11-01

    Influence of uniaxial pressure (0-1000 bars) applied parallel to or perpendicularly to the ac or dc electric field (in one-dimensional or two-dimensional manner) on dielectric and ferroelectric properties of hard lead zirconate titanate (PZT) ceramics were investigated. The experimental results revealed that applying uniaxial pressure leads to a reduction in the peak intensity of the electric permittivity (?), of the frequency dispersion as well as of the dielectric hysteresis. Moreover, with increasing pressure the peak intensity of ? becomes diffused and shifts to a higher temperature. It was also found that simultaneous application of uniaxial pressure and electric field (perpendicular to each other) in the poling process improves the ferroelectric properties. This indeed indicates new possibility for poling materials with a high coercive field and/or high electric conductivity. The effects of uniaxial load are weaker than that obtained for soft PZT ceramics. It was concluded that applying uniaxial pressure induces similar effects as increasing the Ti ion concentration in PZT system. The obtained results were interpreted through Cochran soft mode and domain switching processes under applying of pressure.

  13. High-frequency properties of PZT for RF-communication applications

    Microsoft Academic Search

    Hong-Jin Zhao; Tian-Ling Ren; Ning-Xin Zhang; Ru-Zhong Zuo; Xiao-Hui Wang; Li-Tian Liu; Zhi-Jian Li; Zhi-Lun Gui; Long-Tu Li

    2003-01-01

    Lead–zirconate–titanate (PbZr0.53Ti0.47O3) nano powders and ceramics were prepared using a sol–gel method. Phase characterization of the lead–zirconate–titanate (PZT) material was identified by X-ray diffraction analysis (XRD). Micro-structure of the samples was examined by the scanning electron microscopy (SEM). Ferroelectric hysteresis loop, high-frequency dielectric response and piezoelectric constant d33 were measured. The remnant polarization (Pr) of the PZT ceramics pellet is

  14. Determination of metal impurities in advanced lead zirconate titanate ceramics by axial view mode inductively coupled plasma optical emission spectrometry.

    PubMed

    Villanueva Tagle, M E; Larrea Marín, M T; Martin Gavilán, O; Durruthy Rodríguez, M D; Calderón Piñar, F; Pomares Alfonso, M S

    2012-05-30

    An inductively coupled plasma optical emission spectrometry quantification method for the determination of Al, Ca, Cr Cu, Fe, Mn, Mg, Ni, Zn, Ba, K, In and Co in lead zirconate-titanate (PZT) ceramics, modified with strontium and chromium, was developed. Total digestion of ceramics was achieved with a HNO(3), H(2)O(2) and HF (ac) mixture by using a microwave furnace. The sensitivity of the net signal intensity respect to radiofrequency power (P) and nebulizer argon flow (F(N)) variations was strongly dependent of the total excitation energy of line (TEE). For lines with TEE near metastable atoms and ions of argon, an increment of the sensitivities to P and F(N) variation was observed. At robust plasma conditions the matrix effect was reduced for all matrices and analytes considered. The precision of analysis ranged from 3 to 13%, whereas the analytes recoveries in the spiked samples varied, mostly, from 90 to 110%. The detection limits of studied elements were from 0.004 to 10 mg kg(-1). PMID:22608413

  15. Surface micromachined peristaltic pumps using lead zirconate titanate film

    NASA Astrophysics Data System (ADS)

    Hong, Eunki

    In recent years, miniaturization of mass spectrometer systems has been studied for portable chemical and biological sensors. In this study, the design, fabrication and characterization of MEMS pumps which could be integrated into a MEMS mass spectrometer was investigated. The MEMS pumps were designed as peristaltic pumps with three interconnected chambers. Sequential motion of the piezoelectric diaphragms on these chambers effect pumping. Diaphragm actuators driven with ring-shaped interdigitated transducer (IDT) electrodes were required to generate deflections of several micrometers. This design used SiO2 and PZT as the passive and active layers, respectively. Zirconia films were used as barrier layers to prevent the rapid diffusion of Pb in PZT into the SiO2 at crystallization temperatures. The residual stresses of SiO2, PZT, and ZrO 2 were evaluated to be -147, 100--150 and 230--270 MPa after the final film deposition. Diaphragm actuators were fabricated by bulk micromachining. The PZT in the actuators showed good dielectric; and ferroelectric properties. The dielectric constants were around 660 with dielectric losses of below 2% at 10 kHz. The remanent polarizations and coercive fields were 20 muC/cm2 and 50 kV/cm. The diaphragm actuators behaved more like membranes than plates and had a residual stress of 86 MPa. Non-180° domain motion of the PZT layer in diaphragm actuators was limited due to the residual stress and clamping by the elastic passive silicon oxide. For 980 mum diameter diaphragm actuators with an IDT spacing of 10 mum, center deflections of around 4.3 mum, larger than the thickness of the structure, were obtained at a voltage of 120 V. The deflection profiles had a funnel shape due to the relative contributions of d31 and d33 piezoelectric coefficients. In addition, the deflection profiles from IDT-mode diaphragm actuators were modified using annular IDT electrodes with inactive center areas. For a given voltage applied to the electrodes, the deflection decreases with increasing percentage of inactive area. However, the deflection profile is much flatter for diaphragms with a higher percentage of inactive area, resulting in a larger stroke volume for the MEMS pumps. The MEMS pumps were fabricated by surface micromachining. The fabrication steps included formation of chamber and channel structures by reactive ion etching (RIE) and subsequent release of diaphragm structures using a XeF 2 process. Ion-milling was used to form portholes for the pump structure. The diaphragm actuators in the structures generated enough deflection to touch the bottom of chambers 3--4 mum deep. Sequential motion of the diaphragm actuators in a three stage peristaltic pump was demonstrated.

  16. Microemulsion Synthesis of Nanoparticle PZT Powder

    Microsoft Academic Search

    M. Amiriyan; Z. A. Nemati; M. S. Rahmanifar; S. Ramesh; S. Meenaloshini; R. Tolouei

    2011-01-01

    Nanocrystalline lead zirconate titanate (PZT) powders have been synthesized using microemulsion processing route. Microemulsion is one of the major processing techniques to synthesize a nanosize, homogenous, and almost agglomerate free ceramic powders. The ternary microemulsion system is consisted of cyclohexane as the oil phase, Triton X100 as the nonionic surfactant phase, and an aqueous phase containing 0.619 M Pb2+, 0.325

  17. Dynamic magnetoelectric effects in bulk and layered composites of cobalt zinc ferrite and lead zirconate titanate

    Microsoft Academic Search

    G. Srinivasan; R. Hayes; C. P. DeVreugd; V. M. Laletsin; N. Paddubnaya

    2005-01-01

    Low-frequency magnetoelectric (ME) coupling is investigated in bulk samples and multilayers of cobalt zinc ferrite, Co 1-xZn xFe 2O 4 (x=0–0.6), and lead zirconate titanate. In bulk samples, the transverse and longitudinal couplings are weak and of equal magnitude. A substantial strengthening of ME interactions is evident in layered structures, with the ME voltage coefficient a factor of 10–30 higher

  18. Field forced antiferroelectric-to-ferroelectric switching in modified lead zirconate titanate stannate ceramics

    Microsoft Academic Search

    Wuyi Pan; Qiming Zhang; Amar Bhalla; Leslie E. Cross

    1989-01-01

    Electric-field-forced antiferroelectric- to-ferroelectric phase transitions in several compositions of modified lead zirconate titanate stannate antiferroelectric ceramics are studied for ultra-high-field-induced strain actuator applications. Two types of fatigue effects are observed in these ceramic compositions. In one, the fatigue effects only proceed to a limited extent and the properties may be restored by annealing above the Curie temperature, while in the

  19. Specific features of switching processes in soft ferroelectric ceramics based on lead zirconate-titanate

    NASA Astrophysics Data System (ADS)

    Akbaeva, G. M.; Borodin, V. Z.

    2015-03-01

    Switching processes in soft ferroelectric ceramic materials based on lead zirconate-titanate have been studied. It has been found that these materials, which possess properties of relaxors and have an additional low-frequency phase transition between two rhombohedral phases, R3 c ? R3 m, exhibit specific features upon the repolarization near this transition: in addition to the decrease in the coercive field, the domain compression effect disappears, which indicates changes in the switching mechanism.

  20. Photostrictive effect in lanthanum-modified lead zirconate titanate ceramics near the morphotropic phase boundary

    Microsoft Academic Search

    Patcharin Poosanaas; Kenji Uchino

    1999-01-01

    Photostrictive effect in lanthanum-modified lead zirconate titanate (PLZT) ceramics, one of the promising candidates for photostrictive materials, has been investigated with different contents of La and the ratio of Zr\\/Ti near the morphotropic phase boundary compositions. The maximum photocurrent and photovoltage were obtained at different compositions of PLZT ceramics: maximum photocurrent at 4\\/48\\/52, maximum photovoltage at 5\\/54\\/46. New figures of

  1. Microstructural Evolution under Polarization Switching of Ferroelectric Tin-modified Lead Zirconate Titanate Ceramics

    Microsoft Academic Search

    Yung-Fu Tsun; Chen-Chia Chou

    1999-01-01

    Electric fatigue properties of ferroelectric niobium-doped tin-modified lead zirconate titanate (PNZST) ceramics were investigated using polarization-electric field (P E) measurements, and the corresponding microstructure evolution was studied employing transmission electron microscopy. The results show that domain boundaries are induced under repeated electric field application, and the microstructures become more complicated due to domain intersection. The mobility of domain boundaries degrades

  2. Electric-field-induced reorientation and flip in domain magnetization and light diffraction in an yttrium-iron-garnet/lead-zirconate-titanate bilayer

    NASA Astrophysics Data System (ADS)

    Zavislyak, I. V.; Sohatsky, V. P.; Popov, M. A.; Srinivasan, G.

    2013-04-01

    A continuous reorientation and an abrupt flip to a canted structure in the magnetization of stripe domains are observed under the influence of an electric field in an yttrium-iron-garnet (YIG)/lead-zirconate-titanate (PZT) bilayer. Magneto-optic techniques have been utilized for the observation of the domain structure and the magnetization flip. It is found that electrically generated mechanical stress in PZT induces an uniaxial anisotropy field in YIG, which is large enough to initially cause a gradual change in the domain magnetization and then a transition from out-of-plane orientation to a canted state for a threshold electric field. Additional evidence for the spin flip has been obtained from data on the modulation of intensity of linearly polarized light due to diffraction by the stripe domains. A comprehensive theory for the voltage-induced magnetization flip is discussed and compared with the data. The magnetic transitions and the theory discussed here are of interests for electric-field-controlled magneto-optic and spintronic devices.

  3. Effect of external fields on the switching current in PZT ferroelectric ceramics

    Microsoft Academic Search

    Heng Chang Nie; Xue Feng Chen; Ning Bo Feng; Gen Shui Wang; Xian Lin Dong; Yan Gu; Hong Liang He; Yu Sheng Liu

    2010-01-01

    The dependence of a switching current in lead zirconate titanate (PZT) ferroelectric ceramics on the temperature and an applied electrical field was investigated. It was found that temperature has a moderate contribution to the switching current values, but applied electric fields have significant effects on the values. Importantly, a relaxation of switching current on frequency was observed through this method.

  4. Impact Damage Detection in Composite Laminates Using PVDF and PZT Sensor Signals

    Microsoft Academic Search

    In-Gul Kim; Hong-Young Lee; Jin-Won Kim

    2005-01-01

    Low-velocity impact damage is a major concern in the design of structures made of composite materials, because impact damage is hidden and cannot be detected by visual inspection. Piezoelectric sensors can be used to detect variations in structural and material properties for structural health monitoring. In this study, polyvinylidene flouride (PVDF) and lead zirconate titanate (PZT) sensors are used for

  5. Effect of sol-gel preparation method on particle morphology in pure and nanocomposite PZT thin films

    Microsoft Academic Search

    Helena Bruncková; ?ubomír Medvecký; Pavol Hvizdoš

    Double-scale composite lead zirconate titanate Pb(Zr0.52Ti0.48)O3 (PZT) thin films of 360 nm thickness were prepared by a modified composite sol-gel method. PZT films were deposited from\\u000a both the pure sol and the composite suspension on Pt\\/Al2O3 substrates by the spin-coating method and were sintered at 650°C. The composite suspension formed after ultrasonic mixing\\u000a of the PZT nanopowder and PZT sol

  6. Nonlinear optical diagnostics of local crystallization of lead zirconate titanate films using femtosecond laser radiation

    NASA Astrophysics Data System (ADS)

    Elshin, A. S.; Firsova, N. Yu.; Marchenkova, M. A.; Emel'yanov, V. I.; Pronin, I. P.; Senkevich, S. V.; Mishina, E. D.; Sigov, A. S.

    2015-05-01

    Features of crystallization of microstructures to the perovskite-like phase in a lead zirconate titanate film are studied using multiple near-IR femtosecond laser pulse radiation. The kinetics of crystallization is in situ investigated using the second-harmonic generation technique. It is established that the crystallization is divided into high-temperature ultrafast (explosive) crystallization, which occurs right after the start of irradiation, and low-temperature slow (self-induced) crystallization, which starts after termination of irradiation of a strained multilayer structure. The advantages of the second-harmonic generation microscopy in studying annealed microstructures are demonstrated.

  7. Field forced antiferroelectric-to-ferroelectric switching in modified lead zirconate titanate stannate ceramics

    SciTech Connect

    Pan, W.; Zhang, Q.; Bhalla, A.; Cross, L.E. (Materials Research Lab., Pennsylvania State Univ., University Park, PA (US))

    1989-04-01

    Electric-field-forced antiferroelectric- to-ferroelectric phase transitions in several compositions of modified lead zirconate titanate stannate antiferroelectric ceramics are studied for ultra-high-field-induced strain actuator applications. Two types of fatigue effects are observed in these ceramic compositions. In one, the fatigue effects only proceed to a limited extent and the properties may be restored by annealing above the Curie temperature, while in the other, the fatigue effects proceed to a large extent and the properties cannot be restored completely by heat treatment.

  8. The Effect of Temperature on Bipolar Electrical Fatigue Behavior of Lead Zirconate Titanate Ceramics

    NASA Astrophysics Data System (ADS)

    Pojprapai, Soodkhet; Glaum, Julia

    2012-09-01

    The ferroelectric fatigue behavior of lead zirconate titanate was investigated under different temperatures (room temperature and 125°C). A bipolar electric field of ±1.5 kV/mm at a frequency of 50 Hz was applied to the samples up to 2 × 105 cycles. A markedly different fatigue rate was observed dependent on temperature. The fatigue degradation represented by the loss of polarization and strain increases with the number of cycles and is more pronounced in the case of the lower temperature. Brennan's model based on a logarithmic fatigue rate is applied to explain the temperature effect on fatigue behavior due to the pinning effect.

  9. A poling study of lead zirconate titanate/polyurethane 0-3 composites

    NASA Astrophysics Data System (ADS)

    Lau, S. T.; Kwok, K. W.; Shin, F. G.; Kopf, S.

    2007-08-01

    0-3 composites of lead zirconate titanate particles dispersed in a thermoplastic elastomer polyurethane matrix were fabricated. The dielectric permittivity and loss of the composite film were measured and compared to the theoretical values. The composites were polarized by the ac fields at different frequencies. With the application of the Sawyer-Tower circuit, the D-E hysteresis loops of the composites can be measured during the poling process. By decreasing the poling frequency, the composite sample shows a larger "remanent" polarization at the same poling field. To evaluate the poling effectiveness, the pyroelectric coefficients of the poled composite samples were measured by a dynamic method.

  10. Terahertz-infrared electrodynamics of lead zirconate-titanate films on a platinum sublayer

    NASA Astrophysics Data System (ADS)

    Komandin, G. A.; Porodinkov, O. E.; Spektor, I. E.; Volkov, A. A.; Vorotilov, K. A.; Seregin, D. S.; Sigov, A. S.

    2015-06-01

    The transmission-reflection spectra of a bilayer structure formed on a substrate of single-crystal silicon with transition layers (TiO2-SiO2), which consists of a PbZr0.52Ti0.48O3 ferroelectric thin film and a polycrystalline platinum layer, have been measured in the frequency range of 10-6000 cm-1. The frequency dependences of the real ?'(?) and imaginary ??(?) parts of the permittivity have been simulated by the method of the dispersion analysis, and the parameters of lattice excitations in the lead zirconate-titanate film have been determined. It has been shown that the low-frequency terahertz dynamics exerts the decisive influence on the formation of the dielectric response over the entire studied frequency range.

  11. Deposition of sol-gel derived lanthanum zirconate titanate thin films on copper substrates.

    SciTech Connect

    Narayanan, M.; Kwon, D. K.; Ma, B.; Balchandran, U.; Energy Systems

    2008-06-23

    Lead lanthanum zirconate titanate (PLZT) thin films were directly deposited on copper substrates by chemical solution deposition and crystallized at temperatures of {approx_equal} 650 C under low pO{sub 2} conditions. Although the crystallization conditions used are conducive for copper oxidation, a thin layer ({approx}115 nm) of PLZT was sufficient to protect the underlying copper from oxidation. Films exhibited well saturated hysteresis loops with remanent polarization {approx}24 {micro}C/cm{sup 2} and dielectric constants {approx}730. Indirect evidence suggests that the oxygen vacancies created during the high temperature processing are responsible for the degradation of the electrical properties of these thin films. Techniques for avoiding this problem are proposed.

  12. High rejection, tunable parallel resonance in micromachined lead zirconate titanate on silicon resonators

    NASA Astrophysics Data System (ADS)

    Bedair, Sarah S.; Judy, Daniel; Pulskamp, Jeffrey; Polcawich, Ronald G.; Gillon, Adam; Hwang, Eugene; Bhave, Sunil

    2011-09-01

    This paper presents a micromachined lead zirconate titanate-on-silicon electromechanical resonator, tunable from series to parallel resonance, for either bandstop or bandpass filter applications. Scattering parameter measurements (9.2 V direct current (DC) bias) reveal bandstop rejection levels > 109 dB at 59.74 MHz and passband loss of 40 dB with a -20-dB bandwidth of 25 kHz (0.042%). These compare within 5-dB of the models. Parallel resonance is also observed for an alternate mechanical mode at 182.8 MHz with a 1.5 V DC bias with a rejection of 54.7 dB, a -20 dB bandwidth of 41 kHz (0.022%). This mode is tunable with the electric field to show series resonance.

  13. Characterization of nonlinear behavior in a tunable phase shifter using ferroelectric PZT thin-film capacitors and its effect on system performance

    Microsoft Academic Search

    J. X. Qiu; D. C. Judy; J. S. Pulskamp; R. G. Polcawich; R. Kaul; F. Crowne

    2009-01-01

    In this paper, the nonlinear behavior in a tunable phase shifter using ferroelectric lead zirconate titanate (PZT) thin-film capacitors is described. The phase shifter is of reflection-type consisting of a coplanar waveguide Lange coupler and two ferroelectric PZT varactors on high resistivity silicon substrate. The nonlinearity is characterized by measuring the AM\\/AM and AM\\/PM transfer curves of the device, a

  14. PVDF-PZT nanocomposite film based self-charging power cell.

    PubMed

    Zhang, Yan; Zhang, Yujing; Xue, Xinyu; Cui, Chunxiao; He, Bin; Nie, Yuxin; Deng, Ping; Lin Wang, Zhong

    2014-03-14

    A novel PVDF-PZT nanocomposite film has been proposed and used as a piezoseparator in self-charging power cells (SCPCs). The structure, composed of poly(vinylidene fluoride) (PVDF) and lead zirconate titanate (PZT), provides a high piezoelectric output, because PZT in this nanocomposite film can improve the piezopotential compared to the pure PVDF film. The SCPC based on this nanocomposite film can be efficiently charged up by the mechanical deformation in the absence of an external power source. The charge capacity of the PVDF-PZT nanocomposite film based SCPC in 240 s is ?0.010 ?A h, higher than that of a pure PVDF film based SCPC (?0.004 ?A h). This is the first demonstration of using PVDF-PZT nanocomposite film as a piezoseparator for SCPC, and is an important step for the practical applications of SCPC for harvesting and storing mechanical energy. PMID:24531887

  15. Effect of crystallinity on thermal transport in textured lead zirconate titanate thin films.

    PubMed

    Varghese, Ronnie; Harikrishna, Hari; Huxtable, Scott T; Reynolds, W T; Priya, Shashank

    2014-05-14

    We demonstrate the use of the time domain thermoreflectance (TDTR) technique towards understanding thermal transport in textured Pb(Zr,Ti)O3 (PZT) thin films grown by a sol-gel process on platinized silicon substrates. PZT films were grown with preferred crystallographic orientations of (100), (110), and (111). Grain orientation was controlled by manipulating the heterogeneous nucleation and growth characteristics at the interface between the film and the underlying Pt layer on the substrate. TDTR was used to measure both the PZT film thermal conductivity and the interface thermal conductance between the PZT and Pt as well as that between the PZT and an Al thermoreflectance layer evaporated on the PZT surface. We find a hierarchical dependence of thermal conductivity on the crystallographic orientation of the PZT films and observed differences in the thermal conductances between the Al-PZT and PZT-Pt interfaces for a varying degree of preferred orientations (100), (110), and (111). Thus, the technique based upon nanoscale thermal measurements can be used to delineate PZT samples with different crystallographic orientations. The thermal conductivities of the PZT films with different crystal orientations were in the range of 1.45-1.80 W m(-1) K(-1). The interface thermal conductance between the PZT and Pt layer was in the range of 30-65 MW m(-2) K(-1), while the conductance between the Al layer and PZT was in the range of 90-120 MW m(-2) K(-1). These interfacial conductances exhibit significant correlations to the texture of the PZT film and elemental concentration and densities at those interfaces. PMID:24689852

  16. Develop techniques for ion implantation of PLZT (lead-lanthanum-zirconate-titanate) for adaptive optics

    SciTech Connect

    Batishko, C.R.; Brimhall, J.L.; Pawlewicz, W.T.; Stahl, K.A.; Toburen, L.H.

    1987-07-01

    Research was conducted at Pacific Northwest Laboratory to develop high photosensitivity adaptive optical elements utilizing ion implanted lanthanum-doped lead-zirconate-titanate (PLZT). One centimeter square samples were prepared by implanting ferroelectric and anti-ferroelectric PLZT with a variety of species or combinations of species. These included Ne, O, Ni, Ne/Cr, Ne/Al, Ne/Ni, Ne/O, and Ni/O, at a variety of energies and fluences. An indium-tin oxide (ITO) electrode coating was designed to give a balance of high conductivity and optical transmission at near uv to near ir wavelengths. Samples were characterized for photosensitivity; implanted layer thickness, index of refraction, and density; electrode (ITO) conductivity; and in some cases, residual stress curvature. Thin film anti-ferroelectric PLZT was deposited in a preliminary experiment. The structure was amorphous with x-ray diffraction showing the beginnings of a structure at substrate temperatures of approximately 550/sup 0/C. This report summarizes the research and provides a sampling of the data taken during the report period.

  17. Surface morphology and stress analysis of piezoelectric strontium-doped lead zirconate titanate thin films

    NASA Astrophysics Data System (ADS)

    Sriram, Sharath; Bhaskaran, Madhu; Holland, Anthony S.

    2006-12-01

    Strontium-doped lead zirconate titanate (PSZT) is a piezoelectric ceramic with relatively high values of piezoelectric coefficients. Perovskite oriented PSZT thin films are also reported to exhibit a variety of other properties including ferroelectricity and pyroelectricity. This paper reports on a study of the surface morphology and resulting stress of PSZT thin films, deposited under a variety of RF magnetron sputtering conditions. The study compares PSZT thin films deposited on metal (gold and platinum) coated silicon wafers. The surface morphology of the deposited PSZT thin films was studied using Atomic Force Microscopy (AFM). Grain size and average surface roughness measurements were used to study the quality of the films. The thin film stress was determined using the changes in the radius of curvature of the sample due to an added layer of thin film, and by applying Stoney's equation to relate the stress to the radius of curvature. The variations in the level of stress for different thermodynamic conditions during RF magnetron sputter deposition are also reported.

  18. Study of samarium modified lead zirconate titanate and nickel zinc ferrite composite system

    NASA Astrophysics Data System (ADS)

    Rani, Rekha; Juneja, J. K.; Singh, Sangeeta; Raina, K. K.; Prakash, Chandra

    2015-03-01

    In the present work, composites of samarium substituted lead zirconate titanate and nickel zinc ferrite with compositional formula 0.95Pb1-3x/2 SmxZr0.65Ti0.35O3-0.05Ni0.8Zn0.2Fe2O4 (x=0, 0.01, 0.02 and 0.03) were prepared by the conventional solid state route. X-ray diffraction analysis was carried out to confirm the coexistence of individual phases. Microstructural study was done by using scanning electron microscope. Dielectric constant and loss were studied as a function of temperature and frequency. To study ferroelectric and magnetic properties of the composite samples, corresponding P-E and M-H hysteresis loops were recorded. Change in magnetic properties of electrically poled composite sample (x=0.02) was studied to confirm the magnetoelectric (ME) coupling. ME coefficient (dE/dH) of the samples (x=0 and 0.02) was measured as a function of DC magnetic field.

  19. Crystal structure and electrical properties of bismuth sodium titanate zirconate ceramics.

    PubMed

    Rachakom, Ampika; Jaiban, Panupong; Jiansirisomboon, Sukanda; Watcharapasorn, Anucha

    2012-01-01

    Lead-free bismuth sodium titanate zirconate (Bi0.5Na0.5Ti1-xZrxO3 where x = 0.20, 0.35, 0.40, 0.45, 0.60, and 0.80 mole fraction) [BNTZ] ceramics were successfully prepared using the conventional mixed-oxide method. The samples were sintered for 2 h at temperatures lower than 1,000°C. The density of the BNTZ samples was at least 95% of the theoretical values. The scanning electron microscopy micrographs showed that small grains were embedded between large grains, causing a relatively wide grain size distribution. The density and grain size increased with increasing Zr concentration. A peak shift in X-ray diffraction patterns as well as the disappearance of several hkl reflections indicated some significant crystal-structure changes in these materials. Preliminary crystal-structure analysis indicated the existence of phase transition from a rhombohedral to an orthorhombic structure. The dielectric and ferroelectric properties were also found to correlate well with the observed phase transition. PMID:22221595

  20. Determination of room-temperature creep of soft lead zirconate titanate piezoceramics under static electric fields

    NASA Astrophysics Data System (ADS)

    Zhou, Dayu; Kamlah, Marc

    2005-11-01

    This study focuses on the experimental investigation of the time-dependent effects of a commercial soft lead zirconate titanate material at room temperature. Samples in initially unpoled states were subjected to a cyclic stepwise electric field which was kept constant at different levels for 300 s. Due to ferroelectric domain switching, significant nonlinearity and hysteresis were observed in the overall polarization and strain response. In particular, the material exhibited creep behavior as the applied electric field was held constant over extended periods of time. This creep was caused by microscopic domain switching processes induced gradually during the holding time. The creep was of primary or transient type in nature and depended strongly on the magnitude of the load applied. Most pronounced creep was observed when holding the field close to the coercive field. Logarithmic representation of the polarization or strain versus time curves indicated that the creep behavior could be quantified approximately by the Andrade power law. The creep exponents were determined for different field conditions. The results may help the understanding of the creep mechanism, which in turn provides contributions to improve the performance and reliability of ultrahigh-precision positioning piezoactuators.

  1. Crystal structure and electrical properties of bismuth sodium titanate zirconate ceramics

    PubMed Central

    2012-01-01

    Lead-free bismuth sodium titanate zirconate (Bi0.5Na0.5Ti1-xZrxO3 where x = 0.20, 0.35, 0.40, 0.45, 0.60, and 0.80 mole fraction) [BNTZ] ceramics were successfully prepared using the conventional mixed-oxide method. The samples were sintered for 2 h at temperatures lower than 1,000°C. The density of the BNTZ samples was at least 95% of the theoretical values. The scanning electron microscopy micrographs showed that small grains were embedded between large grains, causing a relatively wide grain size distribution. The density and grain size increased with increasing Zr concentration. A peak shift in X-ray diffraction patterns as well as the disappearance of several hkl reflections indicated some significant crystal-structure changes in these materials. Preliminary crystal-structure analysis indicated the existence of phase transition from a rhombohedral to an orthorhombic structure. The dielectric and ferroelectric properties were also found to correlate well with the observed phase transition. PMID:22221595

  2. Tribological characteristics of probe tip and PZT media for AFM-based recording technology

    Microsoft Academic Search

    Koo-Hyun Chung; Yong-Ha Lee; Dae-Eun Kim; Jingyoo Yoo; Seungbum Hong

    2005-01-01

    The reliability issue of probe tip\\/recording media interface is one of the most crucial concerns in the atomic force microscope (AFM)-based recording technology. In this work, a specialized doped silicon probe tip and a lead zirconate titanate, Pb(ZrxTi1-x)O3(PZT) recording media were prepared for data recording based on ferroelectric interaction, and their tribological characteristics were assessed by performing wear tests using

  3. Tribological characteristics of probe tip and PZT media for AFM-based recording technology

    Microsoft Academic Search

    Koo-Hyun Chung; Yong-Ha Lee; Dae-Eun Kim; Jingyoo Yoo; Seungbum Hong

    2004-01-01

    The reliability issue of the probe tip\\/recording media interface is one of the most crucial concerns in the atomic force microscope (AFM)-based recording technology. In this work, a specialized doped silicon probe tip and a lead zirconate titanate, Pb(ZrxTi1-x)O3 (PZT) recording media were prepared for data recording based on ferroelectric interaction, and their tribological characteristics were assessed by performing wear

  4. A cross-junction channel valveless-micropump with PZT actuation

    Microsoft Academic Search

    Van Thanh Dau; Thien Xuan Dinh; Tanaka Katsuhiko; Sugiyama Susumu

    2009-01-01

    A gas-jet micro pump with novel cross-junction channel has been designed and fabricated using a Si micromachining process.\\u000a The valveless micro pump is composed of a piezoelectric lead zirconate titanate (PZT) diaphragm actuator and fluidic network.\\u000a The design of the valveless pump focuses on a cross-junction formed by the neck of the pump chamber and one outlet and two\\u000a opposite

  5. PZT FOR MEASURING ENERGY FLUENCE RATE OF X-RAY USED IN SUPERFICIAL CANCER THERAPY

    Microsoft Academic Search

    Wesley Pontes; Aparecido Augusto de Carvalho; Walter Katsumi Sakamoto; Mauro Henrique de Paula; Marcelo A. A. Sanches; Ricardo L. B. de Freitas; Regina Borges P. César; Sérgio L. Piubéli

    2010-01-01

    A PZT detector is used for measuring the energy fluence rate of X-ray pulses produced by superficial cancer therapy equipment (orthovoltage range). The instrument consists of a pyroelectric sensor, a low-noise high-sensitivity, current-to-voltage converter, a microcontroller and a digital display. The main element of the instrument is a pyroelectric sensor which consists of an iron-doped lead zirconate titanate ceramic disk.

  6. Fabrication and characterization of micromachined high-frequency tonpilz transducers derived by PZT thick films

    Microsoft Academic Search

    Qifa Zhou; Jonathan M. Cannata; Richard J. Meyer; David J. Van Tol; Srinivas Tadigadapa; W. Jack Hughes; K. Kirk Shung; Susan Trolier-McKinstry

    2005-01-01

    Miniaturized tonpilz transducers are potentially useful for ultrasonic imaging in the 10 to 100 MHz frequency range due to their higher efficiency and output capabilities. In this work, 4 to 10-?m thick piezoelectric thin films were used as the active element in the construction of miniaturized tonpilz structures. The tonpilz stack consisted of silver\\/lead zirconate titanate (PZT)\\/lanthanum nickelate (LaNiO3)\\/silicon on

  7. Effects of Microstructural Variables on the Shock Wave Response of PZT 95\\/5

    Microsoft Academic Search

    ROBERT E. SETCHELL; BRUCE A. TUTTLE; JAMES A. VOIGT

    2003-01-01

    The particular lead zirconate\\/titanate composition PZT 95\\/5-2Nb was identified many years ago as a promising ferroelectric ceramic for use in shock-driven pulsed power supplies. The bulk density and the corresponding porous microstructure of this material can be varied by adding different types and quantities of organic pore formers prior to bisque firing and sintering. Early studies showed that the porous

  8. Elasticity Imaging of Ferroelectric Domain Structure in PZT by Ultrasonic Atomic Force Microscopy

    SciTech Connect

    Tsuji, T. [National Institute of Advanced Industrial Science and Technology, Tsukuba, 3058564 (Japan); Tohoku university, Sendai, Japan 9808579 (Japan); Ogiso, H. [National Institute of Advanced Industrial Science and Technology, Tsukuba, 3058564 (Japan); Fukuda, K.; Yamanaka, K. [Tohoku university, Sendai, 9808579 (Japan)

    2004-02-26

    UAFM was applied to the observation of the domain structure in lead zirconate titanate (PZT). It imaged the change of elasticity due to grain and domain boundary (DB). For the quantitative evaluation of the contact stiffness, the lateral contact stiffness was taken into account. The stiffness of DB was 10% lower than that within the domain and the width of the DB was about 30 nm. The implication of this work is the understanding of the fatigue mechanism in a PZT memory and the high resolution imaging for a high-density memory.

  9. New Fabrication of High-Frequency (100-MHz) Ultrasound PZT Film Kerfless Linear Array

    PubMed Central

    Zhu, Benpeng; Chan, Ngai Yui; Dai, Jiyan; Shung, K. Kirk; Takeuchi, Shinichi; Zhou, Qifa

    2013-01-01

    The paper describes the design, fabrication, and measurements of a high-frequency ultrasound kerfless linear array prepared from hydrothermal lead zirconate titanate (PZT) thick film. The 15-µm hydrothermal PZT thick film with an area of 1 × 1 cm, obtained through a self-separation process from Ti substrate, was used to fabricate a 32-element 100-MHz kerfless linear array with photolithography. The bandwidth at ?6 dB without matching layer, insertion loss around center frequency, and crosstalk between adjacent elements were measured to be 39%, ?30 dB, and ?15 dB, respectively. PMID:23549547

  10. Effect of composition and temperature on field-induced properties in the lead strontium zirconate titanate system

    NASA Astrophysics Data System (ADS)

    Yu, Yongjian; Singh, Raj N.

    2000-12-01

    The electric field-induced antiferroelectric (AFE) to ferroelectric (FE) phase transition in lead strontium zirconate titanate (PSZT) ceramics was studied by means of dielectric, polarization, and strain hysteresis measurements. PSZT compositions with varying strontium and Zr/Ti ratio, located in the ferroelectric, antiferroelectric phase regions, and near the AFE/FE phase boundary were prepared. Dielectric properties were measured as a function of temperature for different compositions. The electric field required for AFE-FE phase transition and hysteresis were affected by the temperature and composition. The entropy change during phase transition and the field-induced strain were also measured and discussed.

  11. Design and simulation of PZT-based MEMS piezoelectric sensors

    NASA Astrophysics Data System (ADS)

    Baker, Doyle J.; Gonder, Casey; Williams, Frances; Bahoura, Messaoud; Myers, Oliver

    2014-03-01

    Devices with increased sensitivities are needed for various applications including the detection of chemical and biological agents. This paper presents the design of microelectromechanical systems (MEMS) devices that incorporate lead zirconate titanate (PZT) films in order to realize highly sensitive sensors. In this work, the piezoelectric properties of the PZT are exploited to produce sensors that perform optimally for mass sensing applications. The sensor is designed to operate as a thin-film bulk acoustic resonator (TFBAR) whereas a piezoelectric is sandwiched between electrodes and senses a change in mass by measuring a change in resonance frequency. Modeling of the TFBAR sensor, using finite element analysis software COMSOL, was performed to examine optimal device design parameters and is presented in this paper. The effect of the PZT thickness on device resonance is also presented. The piezoelectric properties of the PZT is based on its crystal structure, therefore, optimization of the PZT film growth parameters is also described in this work. A detailed description of the fabrication process flow developed based on the optimization of the device design and film growth is also given. The TFBAR sensor consists of 150 nm of PZT, 150nm of silicon dioxide, silicon substrate, titanium/platinum bottom electrodes, and aluminum top electrodes. The top electrodes are segmented to increase the sensitivity of the sensor. The resonance frequency of the device is 3.2 GHz.

  12. Microemulsion Synthesis of Nanoparticle PZT Powder

    NASA Astrophysics Data System (ADS)

    Amiriyan, M.; Nemati, Z. A.; Rahmanifar, M. S.; Ramesh, S.; Meenaloshini, S.; Tolouei, R.

    2011-01-01

    Nanocrystalline lead zirconate titanate (PZT) powders have been synthesized using microemulsion processing route. Microemulsion is one of the major processing techniques to synthesize a nanosize, homogenous, and almost agglomerate free ceramic powders. The ternary microemulsion system is consisted of cyclohexane as the oil phase, Triton X100 as the nonionic surfactant phase, and an aqueous phase containing 0.619 M Pb2+, 0.325 M Zr4+, and 0.3 M Ti4+, representing a Pb2+: Zr4+: Ti4+ molar ratio of 1:0.52:0.48. The ratio of these cations has been adjusted using Inductively Coupled Plasma (ICP) technique. After coprecipitation of metallic hydroxides by adding ammonia solution in microemulsion system, the PZT precursor was obtained. PZT powders have been prepared upon calcination of precursor at 800° C. Prepared powders was characterised using techniques such as X-ray diffraction, differential thermal analysis, and scanning electron microscopy. The characteristics of microemulsion processed powder is discussed, with emphasis on the presence of nano scaled PZT powder with a composition near to morphotropic phase boundary (MPB) without formation of any intermediate phases.

  13. NOVEL LEAD ZIRCONATE TITANATE COMPOSITE VIA FREEZING TECHNOLOGY FOR HIGH FREQUENCY TRANSDUCER APPLICATIONS

    PubMed Central

    ZHU, B. P.; ZHOU, Q. F.; HU, C. H.; SHUNG, K. K.; GORZKOWSKI, E. P.; PAN, M. J.

    2011-01-01

    Novel PZT-5A ceramic-polymer composite was prepared via freezing technology. This composite exhibited good dielectric and ferroelectric behaviors. At 1 kHz, the dielectric constant and the dielectric loss were 546 and 0.046, respectively, while the remnant polarization was 13.0 ?C/cm2 at room temperature. The electromechanical coupling coefficient (kt) of PZT-5A composite was measured to be 0.54, which is similar to that of PZT piezoelectric ceramic. The piezoelectric coefficient (d33) of PZT-5A composite was determined to be ~250 pC/N. Using this composite, a 58MHz single element transducer with the bandwidth of 70% at ?6dB was built, and the insertion loss was tested to be ?29dB around the central frequency. PMID:21785672

  14. A study of lead zirconate titanate etching characteristics using magnetized inductively coupled plasmas

    Microsoft Academic Search

    Y. J. Lee; H. R. Han; J. Lee; G. Y. Yeom

    2000-01-01

    In this study, Pb(Zr1?xTix)O3 (PZT) thin films were etched using magnetized inductively coupled plasmas (MICP) and their etch characteristics were compared with those by non-magnetized conventional inductively coupled plasmas (ICP). The use of Helmholtz type axial electromagnets around the chamber wall increased the PZT etch rates while decreasing etch uniformity. By using both the multidipole magnets and the axial electromagnets

  15. Effects of the poling process on dielectric, piezoelectric, and ferroelectric properties of lead zirconate titanate

    NASA Astrophysics Data System (ADS)

    Prewitt, Anderson D.

    Smart materials are widely used in many of today's relevant technologies such as nano and micro electromechanical systems (NEMS and MEMS), sensors, actuators, nonvolatile memory, and solid state devices. Many of these systems rely heavily on the electromechanical properties of certain smart materials, such as piezoelectricity and ferroelectricity. By definition, piezoelectricity is a mechanical stress in a material that produces an electric displacement (known as the direct piezoelectric effect) or electrical charge in a material which produces a mechanical strain (known as the converse piezoelectric effect). Ferroelectricity is a sub-class of piezoelectricity in which the polarization occurs spontaneously and the dipoles can be reoriented. Domain walls are the nanoscale regions separating two finite distinctively polarized areas in a ferroelectric. The reorientation of polarization in a material is called the poling process and many factors can influence the effectiveness of this process. A more fundamental understanding of how electrical and mechanical loading changes the domain structure of these materials could lead to enhanced properties such as increased energy transduction and decreased nonlinear behavior. This research demonstrates the influence of mechanical pressure and electrical field during and after the poling process on domain walls. The effects of strong mechanical forces on large-scale domain switching and weak cyclic forces on small-scale domain wall motion are investigated to show how they affect the macroscopic behavior of these materials. Commercial lead zirconate titanate ceramics were studied under various poling conditions and the effect of domain wall motion on the piezoelectric, dielectric, and ferroelectric properties was investigated. Polarization and strain measurements from samples poled at specific conditions and converse piezoelectric coefficient and dielectric permittivity data was extracted and interpreted in the context of Rayleigh Law. Direct d33 was also measured. Mechanical loading measurements on the samples were conducted in situ during neutron diffraction experiments to determine how the domain structure behaved for the various poling conditions. The behavior of unpoled and poled samples under load was investigated. The goal of this research is to develop a better understanding of the ferroelectric poling process and its influence on domain wall behavior in order to better engineer material and device properties. Experimental results have shown that significant changes occur in the electromechanical behavior of the material depending on the poling conditions. These results provide insight on how to better design materials and devices with enhanced performance, improved capacity, and less degradation as a result of mechanical stress and electrical fields. Possible microstructural origins for this behavior are discussed.

  16. Highly dense and crack free 50-?m-Thick PZN-PZT films by aerosol deposition method

    Microsoft Academic Search

    Jong-Jin Choi; Byung-Dong Hahn; Woon-Ha Yoon; Dong-Soo Park; Jungho Ryu

    2007-01-01

    Lead zinc niobate -lead zirconate titanate (PZN-PZT) thick films with thickness of ~50 ?m were deposited on silicon and alumina substrates using aerosol deposition method (ADM). The effects of excess lead oxide (PbO) on stress relaxation during post-annealing were studied. Excess PbO content was varied from 0 to 5 mol%. The as-deposited film had fairly dense microstructure with nano-sized grains.

  17. Optical and electrical properties of polycrystalline and amorphous PZT thin films prepared by the sol-gel technique

    Microsoft Academic Search

    Yuhuan Xu; Chih-Hsing Cheng; John D. MacKenzie

    1994-01-01

    Lead zirconate titanate thin films on silicon wafers and titanium foils were fabricated by the sol-gel technique. Polycrystalline and amorphous PZT thin films were obtained at the heat- treatment temperature of 650 degree(s)C and 400 degree(s)C, respectively. The microstructures of these films ere determined by x-ray and electron diffraction and HRTEM techniques. the optical refractive index of both polycrystalline and

  18. BaPbO3 perovskite electrode for lead zirconate titanate ferroelectric thin films

    NASA Astrophysics Data System (ADS)

    Luo, Yih-Rong; Wu, Jenn-Ming

    2001-11-01

    BaPbO3 (BPO) films were prepared by rf-magnetron sputtering at temperatures as low as 350 °C. These films possessed low electrical resistivity of 1.4×10-3 ? cm, which is appropriate for electrodes. The BPO electrode has an advantage over a Pt electrode in that it lowers the crystallization temperature of Pb(Zr0.53Ti0.47)O3 (PZT) films from 600 to 550 °C. The coercive fields of the PZT films deposited on a BPO/Pt electrode are significantly lower than those deposited on the Pt electrode, but the remanent polarization remained essentially unchanged. The BPO electrode also improved the fatigue resistance and decreased the leakage current of the PZT films deposited.

  19. Dielectric properties of lead lanthanum zirconate titanate thin films with and without ZrO2 insertion layers

    NASA Astrophysics Data System (ADS)

    Liu, Shanshan; Ma, Beihai; Narayanan, Manoj; Tong, Sheng; Koritala, Rachel E.; Hu, Zhongqiang; Balachandran, Uthamalingam

    2013-05-01

    The dielectric properties of lead lanthanum zirconate titanate (PLZT) thin films on platinized silicon (Pt/Si) with and without ZrO2 insertion layers were investigated in the temperature range from 20 °C to 300 °C. Permittivity, dielectric loss tangent, and tunability were reduced for the samples with ZrO2 insertion layers compared to those without the layers. Additionally, the permittivity was less dependent on frequency over the broad temperature range studied (20-300 °C). The leakage current behavior of the PLZT films with and without ZrO2 insertion layers was also investigated, and on the basis of those results, a probable conduction mechanism has been suggested. The improved electrical properties in the PLZT with ZrO2 layers are attributed to the ZrO2 layer blocking the mobile ionic defects and reducing free charge carriers to transport.

  20. Thermal lens and Auger upconversion losses' effect on the efficiency of Nd3+-doped lead lanthanum zirconate titanate transparent ceramics

    NASA Astrophysics Data System (ADS)

    de Camargo, Andrea S. S.; Jacinto, Carlos; Catunda, Tomaz; Nunes, Luiz Antonio De O.; Garcia, Ducinei; Eiras, José Antonio

    2006-10-01

    A thorough investigation of optical losses for the 1064nm emission in Nd3+-doped lead lanthanum zirconate titanate (PLZT) transparent ceramics is presented. Thermal lens experiments were carried out to evaluate thermo-optical properties and the fluorescence quantum efficiency of the emitting level 4F3/2. Excited-state absorption losses were measured in the emitting wavelength region, and the Auger upconversion energy transfer parameter ? was calculated. By using ?, the pump-intensity dependence of the optical gain at 1064nm, the fluorescence quantum efficiency, and the generation of heat in the ceramic were simulated for a high 803nm pump-power regime. Since the radiative and nonradiative losses in Nd:PLZT were verified to be considerably lower than in various commercial laser crystals and glasses, it is suggested that this material might become an interesting alternative for high-power laser emission.

  1. Modified Johnson model for ferroelectric lead lanthanum zirconate titanate at very high fields and below Curie temperature.

    SciTech Connect

    Narayanan, M.; Tong, S.; Ma, B.; Liu, S.; Balachandran, U. (Energy Systems)

    2012-01-01

    A modified Johnson model is proposed to describe the nonlinear field dependence of the dielectric constant ({var_epsilon}-E loop) in ferroelectric materials below the Curie temperature. This model describes the characteristic ferroelectric 'butterfly' shape observed in typical {var_epsilon}-E loops. The predicted nonlinear behavior agreed well with the measured values in both the low- and high-field regions for lead lanthanum zirconate titanate films. The proposed model was also validated at different temperatures below the ferroelectric-to-paraelectric Curie point. The anharmonic coefficient in the model decreased from 6.142 x 10{sup -19} cm{sup 2}/V{sup 2} to 2.039 x 10{sup -19} cm{sup 2}/V{sup 2} when the temperature increased from 25 C to 250 C.

  2. Characterization of lead zirconate titanate piezoceramic using high frequency ultrasonic spectroscopy

    E-print Network

    Cao, Wenwu

    for ultrasonic spectroscopy measurements. Shear wave spectrum was obtained through mode conversion using a pair widely used in the characterization of solid materials. With angular incidence, mode conversion effect on the theoretical analysis, an ultrasonic spectroscopy technique suitable for character- ization of PZT ceramic

  3. Domain pinning near a single-grain boundary in tetragonal and rhombohedral lead zirconate titanate films

    NASA Astrophysics Data System (ADS)

    Marincel, D. M.; Zhang, H. R.; Britson, J.; Belianinov, A.; Jesse, S.; Kalinin, S. V.; Chen, L. Q.; Rainforth, W. M.; Reaney, I. M.; Randall, C. A.; Trolier-McKinstry, S.

    2015-04-01

    The interaction of grain boundaries with ferroelectric domain walls strongly influences the extrinsic contribution to piezoelectric activity in Pb Zr1 -x,TixO3 (PZT), ubiquitous in modern transducers and actuators. However, the fundamental understanding of these phenomena has been limited by complex mechanisms originating from the interplay of atomic-level domain wall pinning, collective domain wall dynamics, and emergent mesoscopic behavior. This contribution utilizes engineered grain boundaries created by depositing epitaxial PZT films with various Zr:Ti ratios onto 24° tilt SrTi O3 bicrystals. The nonlinear piezoelectric response and surface domain structure across the boundary are investigated using piezoresponse force microscopy while the cross-sectional domain structure is studied using transmission electron microscopy. The grain boundary reduces domain wall motion over a width of 800 ±70 nm for PZT 45:55 and 450 ±30 nm for PZT 52:48. Phase field modeling provides an understanding of the elastic and electric fields associated with the grain boundary and local domain configurations. This study demonstrates that complex mesoscopic behaviors can be explored to complement atomic-level pictures of the material system.

  4. From lab to industrial: PZT nanoparticles synthesis and process control for application in additive manufacturing

    NASA Astrophysics Data System (ADS)

    Huang, Hsien-Lin

    Lead Zirconate Titanate (PZT) nanoparticles hold many promising current and future applications, such as PZT ink for 3-D printing or seeds for PZT thick films. One common method is hydrothermal growth, in which temperature, duration time, or mineralizer concentrations are optimized to produce PZT nanoparticles with desired morphology, controlled size and size distribution. A modified hydrothermal process is used to fabricate PZT nanoparticles. The novelty is to employ a high ramping rate (e.g., 20 deg C/min) to generate abrupt supersaturation so as to promote burst nucleation of PZT nanoparticles as well as a fast cooling rate (e.g., 5 deg C/min) with a controlled termination of crystal growth. As a result, PZT nanoparticles with a size distribution ranging from 200 nm to 800 nm are obtained with cubic morphology and good crystallinity. The identification of nanoparticles is confirmed through use of X-ray diffractometer (XRD). XRD patterns are used to compare sample variations in their microstructures such as lattice parameter. A cubic morphology and particle size are also examined via SEM images. The hydrothermal process is further modified with excess lead (from 20% wt. to 80% wt.) to significantly reduce amorphous phase and agglomeration of the PZT nanoparticles. With a modified process, the particle size still remains within the 200 nm to 800 nm. Also, the crystal structures (microstructure) of the samples show little variations. Finally, a semi-continuous hydrothermal manufacturing process was developed to substantially reduce the fabrication time and maintained the same high quality as the nanoparticles prepared in an earlier stage. In this semi-continuous process, a furnace is maintained at the process temperature (200 deg C), whereas autoclaves containing PZT sol are placed in and out of the furnace to control the ramp-up and cooling rates. This setup eliminates an extremely time-consuming step of cooling down the furnace, thus saving tremendous amount of process time making fabrication of a large amount of PZT nanoparticles possible.

  5. Temperature dependent mechanical property of PZT film: an investigation by nanoindentation.

    PubMed

    Li, Yingwei; Feng, Shangming; Wu, Wenping; Li, Faxin

    2015-01-01

    Load-depth curves of an unpoled Lead Zirconate Titanate (PZT) film composite as a function of temperature were measured by nanoindentation technique. Its reduce modulus and hardness were calculated by the typical Oliver-Pharr method. Then the true modulus and hardness of the PZT film were assessed by decoupling the influence of substrate using methods proposed by Zhou et al. and Korsunsky et al., respectively. Results show that the indentation depth and modulus increase, but the hardness decreases at elevated temperature. The increasing of indentation depth and the decreasing of hardness are thought to be caused by the decreasing of the critical stress needed to excite dislocation initiation at high temperature. The increasing of true modulus is attributed to the reducing of recoverable indentation depth induced by back-switched domains. The influence of residual stress on the indentation behavior of PZT film composite was also investigated by measuring its load-depth curves with pre-load strains. PMID:25768957

  6. Electrostatic and dielectric response in lead magnesium niobate-lead titanate (0. 9PMNter dot 0. 1PT) and lead lanthanum zirconate titanate (PLZT 9. 5/65/35) under variation of temperature and electric field

    SciTech Connect

    Zhang, Q.; Pan, W.; Bhalla, A.; Cross, L.E. (Materials Research Lab., Pennsylvania State Univ., University Park, PA (US))

    1989-04-01

    In situ measurements of electrostrictive strain and effective dielectric constant for two ferroelectric relaxor materials, lead magnesium niobate-lead titanate (0.9PMN {center dot} 0.1PT) and lead lanthanum zirconate titanate (PLZT 9.5/65/35), were performed in the temperature ranges near their respective mean Curie points under the variation of applied electric field. The measurement results show that the polarization-related electrostrictive coefficients Q{sub y} are not constant under variation of temperature and electric field. The data also support the idea that at temperatures far above the mean Curie point, there is still a substantial amount of micropolar domain.

  7. Electro-Optic Properties of Lanthanum-Modified Lead Zirconate Titanate Thin Films Epitaxially Grown by the Advanced Sol-Gel Method

    Microsoft Academic Search

    Kiyoshi Uchiyama; Atsushi Kasamatsu; Yohei Otani; Tadashi Shiosaki

    2007-01-01

    Epitaxially grown lanthanum-modified lead zirconate titanate (PLZT) thin films were deposited on r-cut sapphire substrates using an advanced sol-gel method. The methanol addition into sol-gel solutions brought high quality epitaxial growth of PLZT thin films. This film showed high electro-optic (EO) coefficients that were almost comparable to those of bulk PLZTs. We believe this PLZT deposition technique will open the

  8. Improving yield of PZT piezoelectric devices on glass substrates

    NASA Astrophysics Data System (ADS)

    Johnson-Wilke, Raegan L.; Wilke, Rudeger H. T.; Cotroneo, Vincenzo; Davis, William N.; Reid, Paul B.; Schwartz, Daniel A.; Trolier-McKinstry, Susan

    2012-10-01

    The proposed SMART-X telescope includes adaptive optics systems that use piezoelectric lead zirconate titanate (PZT) films deposited on flexible glass substrates. Several processing constraints are imposed by current designs: the crystallization temperature must be kept below 550 °C, the total stress in the film must be minimized, and the yield on 1 cm2 actuator elements should be < 90%. For this work, RF magnetron sputtering was used to deposit films since chemical solution deposition (CSD) led to warping of large area flexible glass substrates. A PZT 52/48 film that wasdeposited at 4 mTorr and annealed at 550 °C for 24 hours showed no detectable levels of either PbO or pyrochlore second phases. Large area electrodes (1cm x 1 cm) were deposited on 4" glass substrates. Initially, the yield of the devices was low, however, two methods were employed to increase the yield to near 100 %. The first method included a more rigorous cleaning to improve the continuity of the Pt bottom electrode. The second method was to apply 3 V DC across the capacitor structure to burn out regions of defective PZT. The result of this latter method essentially removed conducting filaments in the PZT but left the bulk of the material undamaged. By combining these two methods, the yield on the large area electrodes improved from < 10% to nearly 100%.

  9. Ultrasonic Imaging for Poling Uniformity Measurements in PZT Ceramic Elements

    SciTech Connect

    Jamieson, E.E.

    2000-03-14

    This report summarizes the results of a project sponsored by Honeywell Corporation (formerly AlliedSignal Inc.) Federal Manufacturing and Technologies/Kansas City (FM and T/KC) and conducted jointly with the University of Missouri, Rolla, titled ''Ultrasonic Imaging for Poling Uniformity Measurements in PZT Ceramic Elements.'' In this three-month research project, a series of experiments was performed on soft and hard lead-zirconate-titanate (PZT) structures to determine the effectiveness of ultrasonic measurements as a nondestructive method of evaluating poling quality and uniformity. The study revealed that acoustic velocity correlates well with the degree of poling of PZT structures, as predicted by elastic theory. Additionally, time-of-flight (TOF) imaging was shown to be an ideal tool for viewing the spatial distribution of poled material and of material affected by the electric field beyond the edge of electroded regions. Finally, the effectiveness of ultrasonic methods for flaw detection and evaluation of PZT/stainless steel bonds was also demonstrated.

  10. Effect of External Vibration on PZT Impedance Signature

    PubMed Central

    Yang, Yaowen; Miao, Aiwei

    2008-01-01

    Piezoelectric ceramic Lead Zirconate Titanate (PZT) transducers, working on the principle of electromechanical impedance (EMI), are increasingly applied for structural health monitoring (SHM) in aerospace, civil and mechanical engineering. The PZT transducers are usually surface bonded to or embedded in a structure and subjected to actuation so as to interrogate the structure at the desired frequency range. The interrogation results in the electromechanical admittance (inverse of EMI) signatures which can be used to estimate the structural health or integrity according to the changes of the signatures. In the existing EMI method, the monitored structure is only excited by the PZT transducers for the interrogating of EMI signature, while the vibration of the structure caused by the external excitations other than the PZT actuation is not considered. However, many structures work under vibrations in practice. To monitor such structures, issues related to the effects of vibration on the EMI signature need to be addressed because these effects may lead to misinterpretation of the structural health. This paper develops an EMI model for beam structures, which takes into account the effect of beam vibration caused by the external excitations. An experimental study is carried out to verify the theoretical model. A lab size specimen with different external excitations is tested and the effect of vibration on EMI signature is discussed.

  11. Stress-optic modulator in TriPleX platform using a ezoelectric lead zirconate titanate (PZT) thin film.

    PubMed

    Hosseini, Naser; Dekker, Ronald; Hoekman, Marcel; Dekkers, Matthijn; Bos, Jan; Leinse, Arne; Heideman, Rene

    2015-06-01

    We will demonstrate a stress-optic phase modulator in the passive SiN-based TriPleX platform using a layer of piezoelectric material. Regarding the stress-optic effect, the piezoelectric layer deposited on top of an optical waveguide is employed to control the phase of propagating light in the structure by applying an electrical field across the layer. In this work, it is demonstrated that the stress-optic effect lowers the power consumption by a factor of one million for quasi-DC operation and increases the modulation speed by three orders of magnitude, compared to currently used thermo-optic modulation in the TriPleX platform. PMID:26072771

  12. Piezoelectric ceramic (PZT) modulates axonal guidance growth of rat cortical neurons via RhoA, Rac1, and Cdc42 pathways.

    PubMed

    Wen, Jianqiang; Liu, Meili

    2014-03-01

    Electrical stimulation is critical for axonal connection, which can stimulate axonal migration and deformation to promote axonal growth in the nervous system. Netrin-1, an axonal guidance cue, can also promote axonal guidance growth, but the molecular mechanism of axonal guidance growth under indirect electric stimulation is still unknown. We investigated the molecular mechanism of axonal guidance growth under piezoelectric ceramic lead zirconate titanate (PZT) stimulation in the primary cultured cortical neurons. PZT induced marked axonal elongation. Moreover, PZT activated the excitatory postsynaptic currents (EPSCs) by increasing the frequency and amplitude of EPSCs of the cortical neurons in patch clamp assay. PZT downregulated the expression of Netrin-1 and its receptor Deleted in Colorectal Cancer (DCC). Rho GTPase signaling is involved in interactions of Netrin-1 and DCC. PZT activated RhoA. Dramatic decrease of Cdc42 and Rac1 was also observed after PZT treatment. RhoA inhibitor Clostridium botulinum C3 exoenzyme (C3-Exo) prevented the PZT-induced downregulation of Netrin-1 and DCC. We suggest that PZT can promote axonal guidance growth by downregulation of Netrin-1 and DCC to mediate axonal repulsive responses via the Rho GTPase signaling pathway. Obviously, piezoelectric materials may provide a new approach for axonal recovery and be beneficial for clinical therapy in the future. PMID:24203571

  13. Residual stress relief due to fatigue in tetragonal lead zirconate titanate ceramics

    NASA Astrophysics Data System (ADS)

    Hall, D. A.; Mori, T.; Comyn, T. P.; Ringgaard, E.; Wright, J. P.

    2013-07-01

    High energy synchrotron XRD was employed to determine the lattice strain ?{111} and diffraction peak intensity ratio R{200} in tetragonal PZT ceramics, both in the virgin poled state and after a bipolar fatigue experiment. It was shown that the occurrence of microstructural damage during fatigue was accompanied by a reduction in the gradient of the ?{111}-cos2 ? plot, indicating a reduction in the level of residual stress due to poling. In contrast, the fraction of oriented 90° ferroelectric domains, quantified in terms of R{200}, was not affected significantly by fatigue. The change in residual stress due to fatigue is interpreted in terms of a change in the average elastic stiffness of the polycrystalline matrix due to the presence of inter-granular microcracks.

  14. Effects of Polarization on Mechanical Properties of Lead Zirconate Titanate Ceramics Evaluated by Modified Small Punch Tests

    NASA Astrophysics Data System (ADS)

    Deng, Qihuang; Fan, Yuchi; Wang, Lianjun; Xiong, Zhi; Wang, Hongzhi; Li, Yaogang; Zhang, Qinghong; Kawasaki, Akira; Jiang, Wan

    2012-01-01

    Pb(Zr,Ti)O3 (PZT) ceramics were prepared by the conventional mixed oxide method, and the strength of the resultant PZT ceramics was evaluated using modified small punch (MSP) tests. Load-displacement curve test results showed that the crack-initiation and fracture strengths of PZT ceramics decreased after polarization. The effect of the polarization accelerated the fatigue properties of PZT ceramics. Scanning electron microscopy (SEM) results showed that microcracks were formed before the maximum load in the MSP test, and the first load drop corresponded to crack initiation.

  15. PZT Thin Film Piezoelectric Traveling Wave Motor

    NASA Technical Reports Server (NTRS)

    Shen, Dexin; Zhang, Baoan; Yang, Genqing; Jiao, Jiwei; Lu, Jianguo; Wang, Weiyuan

    1995-01-01

    With the development of micro-electro-mechanical systems (MEMS), its various applications are attracting more and more attention. Among MEMS, micro motors, electrostatic and electromagnetic, are the typical and important ones. As an alternative approach, the piezoelectric traveling wave micro motor, based on thin film material and integrated circuit technologies, circumvents many of the drawbacks of the above mentioned two types of motors and displays distinct advantages. In this paper we report on a lead-zirconate-titanate (PZT) piezoelectric thin film traveling wave motor. The PZT film with a thickness of 150 micrometers and a diameter of 8 mm was first deposited onto a metal substrate as the stator material. Then, eight sections were patterned to form the stator electrodes. The rotor had an 8 kHz frequency power supply. The rotation speed of the motor is 100 rpm. The relationship of the friction between the stator and the rotor and the structure of the rotor on rotation were also studied.

  16. Sensitivity of PZT Impedance Sensors for Damage Detection of Concrete Structures

    PubMed Central

    Yang, Yaowen; Hu, Yuhang; Lu, Yong

    2008-01-01

    Piezoelectric ceramic Lead Zirconate Titanate (PZT) based electro-mechanical impedance (EMI) technique for structural health monitoring (SHM) has been successfully applied to various engineering systems. However, fundamental research work on the sensitivity of the PZT impedance sensors for damage detection is still in need. In the traditional EMI method, the PZT electro-mechanical (EM) admittance (inverse of the impedance) is used as damage indicator, which is difficult to specify the effect of damage on structural properties. This paper uses the structural mechanical impedance (SMI) extracted from the PZT EM admittance signature as the damage indicator. A comparison study on the sensitivity of the EM admittance and the structural mechanical impedance to the damages in a concrete structure is conducted. Results show that the SMI is more sensitive to the damage than the EM admittance thus a better indicator for damage detection. Furthermore, this paper proposes a dynamic system consisting of a number of single-degree-of-freedom elements with mass, spring and damper components to model the SMI. A genetic algorithm is employed to search for the optimal value of the unknown parameters in the dynamic system. An experiment is carried out on a two-storey concrete frame subjected to base vibrations that simulate earthquake. A number of PZT sensors are regularly arrayed and bonded to the frame structure to acquire PZT EM admittance signatures. The relationship between the damage index and the distance of the PZT sensor from the damage is studied. Consequently, the sensitivity of the PZT sensors is discussed and their sensing region in concrete is derived.

  17. Chin. Phys. B Vol. 19, No. 2 (2010) 027201 Current voltage characteristics of lead zirconate

    E-print Network

    Volinsky, Alex A.

    2010-01-01

    Chin. Phys. B Vol. 19, No. 2 (2010) 027201 Current voltage characteristics of lead zirconate lead zirconate titanate/nickel bilayered hollow cylindrical magne- toelectric composite showed voltage across the lead zirconate titanate layer thickness. The current­voltage coefficient

  18. A Reusable PZT Transducer for Monitoring Initial Hydration and Structural Health of Concrete

    PubMed Central

    Yang, Yaowen; Divsholi, Bahador Sabet; Soh, Chee Kiong

    2010-01-01

    During the construction of a concrete structure, strength monitoring is important to ensure the safety of both personnel and the structure. Furthermore, to increase the efficiency of in situ casting or precast of concrete, determining the optimal time of demolding is important for concrete suppliers. Surface bonded lead zirconate titanate (PZT) transducers have been used for damage detection and parameter identification for various engineering structures over the last two decades. In this work, a reusable PZT transducer setup for monitoring initial hydration of concrete and structural health is developed, where a piece of PZT is bonded to an enclosure with two bolts tightened inside the holes drilled in the enclosure. An impedance analyzer is used to acquire the admittance signatures of the PZT. Root mean square deviation (RMSD) is employed to associate the change in concrete strength with changes in the PZT admittance signatures. The results show that the reusable setup is able to effectively monitor the initial hydration of concrete and the structural health. It can also be detached from the concrete for future re-use. PMID:22399929

  19. Application of Multiplexed FBG and PZT Impedance Sensors for Health Monitoring of Rocks

    PubMed Central

    Yang, Yaowen; Annamdas, Venu Gopal Madhav; Wang, Chao; Zhou, Yingxin

    2008-01-01

    Reliable structural health monitoring (SHM) including nondestructive evaluation (NDE) is essential for safe operation of infrastructure systems. Effective monitoring of the rock components of civil infrastructures such as tunnels and caverns remains challenging. The feasibility of employing smart optical fibre sensor (OFS) and piezoelectric impedance sensor made up of lead zirconate titanate (PZT) for comprehensive health monitoring of rocks, covering load history monitoring/retrieval as well as damage assessment is presented in this paper. The rock specimens are subjected to cyclic loading and their conditions are continuously monitored using OFS and PZT sensors. OFS based multiplexed fibre Bragg grating (FBG) sensors are surface bonded on the rock specimens. Their strain sensing performance is compared with the conventional electric strain gauges (ESGs). In addition, PZT patches are also bonded on the specimens to study the damage pattern during different loading cycles. Unlike the FBGs or ESGs, PZT patches are used as bi-functional sensors and actuators, enabling them to be efficient detectors of incipient damages using the principle of electromechanical impedance. The experimental study demonstrated superior performance of these smart FBG and PZT impedance sensors. This work is expected to be useful for SHM based NDE application of rock structures such as caverns and tunnels.

  20. Fabrication and Evaluation of One-Axis Oriented Lead Zirconate Titanate Films Using Metal-Oxide Nanosheet Interface Layer

    NASA Astrophysics Data System (ADS)

    Minemura, Yoshiki; Nagasaka, Kohei; Kiguchi, Takanori; Konno, Toyohiko J.; Funakubo, Hiroshi; Uchida, Hiroshi

    2013-09-01

    Nanosheet Ca2Nb3O20 (ns-CN) layers with pseudo-perovskite-type crystal configuration were applied on the surface of polycrystalline metal substrates to achieve preferential crystal orientation of Pb(Zr,Ti)O3 (PZT) films for the purpose of enhanced ferroelectricity comparable to that of epitaxial thin films. PZT films with tetragonal symmetry (Zr/Ti=0.40:0.60) were fabricated by chemical solution deposition (CSD) on ns-CN-buffered Inconel 625 and SUS 316L substrates, while ns-CN was applied on the the substrates by dip-coating. The preferential crystal growth on the ns-CN layer can be achieved by favorable lattice matching between (001)/(100)PZT and (001)ns-CN planes. The degree of (001) orientation was increased for PZT films on ns-CN/Inconel 625 and ns-CN/SUS 316L substrates, whereas randomly-oriented PZT films with a lower degree of (001) orientation were grown on bare and Inconel 625 films. Enhanced remanent polarization of 60 µC/cm2 was confirmed for the PZT films on ns-CN/metal substrates, ascribed to the preferential alignment of the polar [001] axis normal to the substrate surface, although it also suffered from higher coercive field above 500 kV/cm caused by PZT/metal interfacial reaction.

  1. Single ZnO nanowire-PZT optothermal field effect transistors.

    PubMed

    Hsieh, Chun-Yi; Lu, Meng-Lin; Chen, Ju-Ying; Chen, Yung-Ting; Chen, Yang-Fang; Shih, Wan Y; Shih, Wei-Heng

    2012-09-01

    A new type of pyroelectric field effect transistor based on a composite consisting of single zinc oxide nanowire and lead zirconate titanate (ZnO NW-PZT) has been developed. Under infrared (IR) laser illumination, the transconductance of the ZnO NW can be modulated by optothermal gating. The drain current can be increased or decreased by IR illumination depending on the polarization orientation of the Pb(Zr(0.3)Ti(0.7))O(3) (PZT) substrate. Furthermore, by combining the photocurrent behavior in the UV range and the optothermal gating effect in the IR range, the wide spectrum of response of current by light offers a variety of opportunities for nanoscale optoelectronic devices. PMID:22895012

  2. Fabrication and characterization of laterally-driven piezoelectric bimorph MEMS actuator with sol-gel-based high-aspect-ratio PZT structure

    NASA Astrophysics Data System (ADS)

    Yoshida, Shinya; Wang, Nan; Kumano, Masafumi; Kawai, Yusuke; Tanaka, Shuji; Esashi, Masayoshi

    2013-06-01

    This paper reports on the fabrication and characterization of a novel laterally-driven piezoelectric bimorph micro electro mechanical systems actuator with high aspect-ratio (AR) lead-zirconate-titanate (PZT) structures. The PZT structures (AR=8) sandwiched with Pt sidewall electrodes were fabricated by a nanocomposite sol-gel process with micromachined silicon templates. A single-cantilever-type lateral bimorph actuator was successfully fabricated, and no initial vertical bending was observed, even on a 500 µm long actuator. A lateral displacement of 10 µm was obtained in bimorph actuation at driving voltages of +25 V/-5 V. Then the piezoelectric property of the PZT structure was characterized from the actuator's performance. The lateral piezoelectric actuator has a variety of potential applications as a replacement for electrostatic comb drive actuators occupying a large area.

  3. Large-aperture optical modulator materials. Lead lanthanum zirconate titanate ceramic and lithium niobate crystal show promise as modulator materials for optical transmitters with up to 6-inch apertures

    Microsoft Academic Search

    R. P. Bocker; G. M. Meana; M. A. Monahan; G. C. Mooradian; W. E. Richards; H. F. Taylor

    1977-01-01

    Six categories of active optical materials were found to qualify as potential large-aperture optical modulator material candidates. Two of these, the electro-optical linear Pockels lithium niobate crystals and the ferroelectric ceramic lead lanthanum zirconate titanate wafers showed real promise. Both of these satisfy the requirements of field of view, optical quality, frequency response, and economic availability, and both performed above

  4. An experimental investigation of lead zirconate titanate--epoxy-multi-walled carbon nanotube bulk and flexible thick film composites

    NASA Astrophysics Data System (ADS)

    Banerjee, Sankha

    Piezoelectric sensors and actuators are needed for a wide range of applications from physiological measurement to industrial monitoring systems. Sensors that can be easily integrated with the host, while maintaining high sensitivity and reliability over a wide range of frequencies are not readily feasible and economical with homogenous piezoelectric materials. It is well known that two-phase piezoelectric-epoxy composites offer several benefits over their single phase counterparts, as the properties of the constituent phases combine to improve the range of applicability. However, the piezoelectric properties of these materials suffer from the electrically insulating properties of the epoxy matrix. The electrical properties of the matrix may be enhanced by including electrically conducting inclusions however, less is known about the mechanisms that drive the changes in these properties. Hence, this experimental investigation of sensor materials builds on the previous work in two-phase piezoelectric composites, where the aims are to understand the roles that specific fabrication parameters and inclusion composition play in determining the piezoelectric and dielectric performance the aforementioned composites. The materials under investigation will be comprised of Lead Zirconate Titanate, Epofix Cold-Setting Embedding Resin and multi-walled carbon nanotubes, i.e. the piezoelectric, epoxy and electrical inclusions respectively. Our work suggests that inclusion of MWCNTs enhances the piezoelectric and dielectric properties with increasing volume fraction below the percolation threshold. This work seeks to understand how the processing parameters: poling temperature, poling type and particle distribution influence the contact resistance, space charge double layer at the piezoelectric and conductor interfaces and electric field intensity at the piezoelectric boundary, which all ultimately dictate the piezoelectric and dielectric performance of the composite materials. Conventional solid oxide mixing, spin coating and deposition techniques will be used to fabricate the bulk and thick films. The piezoelectric and dielectric performance will be determined from the measurement of the piezoelectric strain coefficients, d33 and d31, dielectric constant, impedance and dielectric spectrum, dielectric loss tangent, and capacitance. These measurements will be correlated with inclusion size, shape, distribution, and surface morphology observations obtained from the scanning electron microscope (SEM) and transmission electron microscope (TEM).

  5. Analyzing the defect structure of CuO-doped PZT and KNN piezoelectrics from electron paramagnetic resonance.

    PubMed

    Jakes, Peter; Kungl, Hans; Schierholz, Roland; Eichel, Rüdiger-A

    2014-09-01

    The defect structure for copper-doped sodium potassium niobate (KNN) ferroelectrics has been analyzed with respect to its defect structure. In particular, the interplay between the mutually compensating dimeric (Cu(Nb)'''-V(O)··) and trimeric (V(O)··-Cu(Nb)'''-V(O)··)· defect complexes with 180° and non-180° domain walls has been analyzed and compared to the effects from (Cu'' - V(O)··)(x)× dipoles in CuO-doped lead zirconate titanate (PZT). Attempts are made to relate the rearrangement of defect complexes to macroscopic electromechanical properties. PMID:25167144

  6. Static/dynamic trade-off performance of PZT thick film micro-actuators

    NASA Astrophysics Data System (ADS)

    Bienaimé, Alex; Chalvet, Vincent; Clévy, Cédric; Gauthier-Manuel, Ludovic; Baron, Thomas; Rakotondrabe, Micky

    2015-07-01

    Piezoelectric actuators are widespread in the design of micro/nanorobotic tools and microsystems. Studies toward the integration of such actuators in complex micromechatronic systems require the size reduction of these actuators while retaining a wide range of performance. Two main fabrication processes are currently used for the fabrication of piezoelectric actuators, providing very different behaviors: (i) the use of a bulk lead zirconate titanate (PZT) layer and (ii) the use of thin film growth. In this paper, we propose a trade-off between these two extreme processes and technologies in order to explore the performance of new actuators. This resulted in the design and fabrication of thick film PZT unimorph cantilevers. They allowed a high level of performance, both in the static (displacement) and dynamic (first resonance frequency) regimes, in addition to being small in size. Such cantilever sizes are obtained through the wafer scale bonding and thinning of a PZT plate onto a silicon on insulator wafer. The piezoelectric cantilevers have a 26 ?m thick PZT layer with a 5 ?m thick silicon layer, over a length of 4 mm and a width of 150 ?m. Experimental characterization has shown that the static displacements obtained are in excess of 4.8 ?m V?1 and the resonance frequencies are up to 1103 Hz, which are useful for large displacements and low voltage actuators.

  7. Fast and wide-band response infrared detector using porous PZT pyroelectric thick film

    NASA Astrophysics Data System (ADS)

    Wu, C. G.; Sun, X. Y.; Meng, J.; Luo, W. B.; Li, P.; Peng, Q. X.; Luo, Y. S.; Shuai, Y.

    2014-03-01

    Porous lead zirconate titanate (PbZr0.3Ti0.7O3, PZT30/70) thick films and detectors for pyroelectric applications have been fabricated on alumina substrates by screen-printing technology. Low temperature sintering of PZT thick films have been achieved at 850 °C by using Li2CO3 and Bi2O3 sintering aids. The microstructure of PZT thick film has been investigated by X-ray diffraction (XRD) and scanning electron microscopy (SEM). The dielectric properties were measured using HP 4284 at 1 kHz under 25 °C. The permittivity and loss tangent of the thick films were 94 and 0.017, respectively. Curie temperature of PZT thick film was 425 °C as revealed by dielectric constant temperature measurement. The pyroelectric coefficient was determined to be 0.9 × 10-8 Ccm-2 K-1 by dynamic current measurement. Infrared detector sensitive element of dual capacitance was fabricated by laser directly write technology. Detectivity of the detectors were measured using mechanically chopped blackbody radiation. Detectivity ranging from 1.23 × 108 to 1.75 × 108 (cm Hz1/2 W-1) was derived at frequency range from 175.5 Hz to 1367 Hz, and D*'s -3 dB cut-off frequency bandwidth was 1.2 kHz. The results indicate that the infrared detectors based on porous thick films have great potential applications in fast and wide-band frequency response conditions.

  8. An in situ diffraction study of domain wall motion contributions to the frequency dispersion of the piezoelectric coefficient in lead zirconate titanate

    SciTech Connect

    Seshadri, Shruti B.; Prewitt, Anderson D.; Jones, Jacob L. [Department of Materials Science and Engineering, University of Florida, Gainesville, Florida 32611 (United States)] [Department of Materials Science and Engineering, University of Florida, Gainesville, Florida 32611 (United States); Studer, Andrew J. [Bragg Institute, ANSTO, Lucas Heights, New South Wales 2234 (Australia)] [Bragg Institute, ANSTO, Lucas Heights, New South Wales 2234 (Australia); Damjanovic, Dragan [Laboratory of Ceramics, Institute of Materials, Swiss Federal Institute of Technology-EPFL, 1015 Lausanne (Switzerland)] [Laboratory of Ceramics, Institute of Materials, Swiss Federal Institute of Technology-EPFL, 1015 Lausanne (Switzerland)

    2013-01-28

    The contribution of non-180 Degree-Sign domain wall displacement to the frequency dependence of the longitudinal piezoelectric coefficient has been determined experimentally in lead zirconate titanate using time-resolved, in situ neutron diffraction. Under subcoercive electric fields of low frequencies, approximately 3% to 4% of the volume fraction of non-180 Degree-Sign domains parallel to the field experienced polarization reorientation. This subtle non-180 Degree-Sign domain wall motion directly contributes to 64% to 75% of the magnitude of the piezoelectric coefficient. Moreover, part of the 33 pm/V decrease in piezoelectric coefficient across 2 orders of magnitude in frequency is quantitatively attributed to non-180 Degree-Sign domain wall motion effects.

  9. Effects of solution precursor nature on sol-gel derived PZT thin film crystallization behavior and properties

    SciTech Connect

    Schwartz, R.W.; DaSalla, R.S.

    1995-09-01

    In fabricating lead zirconate titanate (PZT) films for nonvolatile memories and decoupling capacitors, various deposition methods have been investigated. Each can produce films with acceptable dielectric and ferroelectric properties, but sol-gel methods offer excellent control of film stoichiometry and coating uniformity. The sol-gel approaches for PZT film fabrication fall into two categories: processes that use 2-methoxyethanol as a solvent, and processes that use chelating agents, such as acetic acid, for reducing the hydrolysis sensitivity of the alkoxide compounds. Due to concerns about the toxicity of 2-methoxyethanol, we have concentrated on the second category. It was found that, in addition to reducing the hydrolysis sensitivity, the chelating agents serves to define the processing behavior of the films: film consolidation after deposition and densification and crystallization during heat treatment. This paper discusses the relations between precursor structure (reactions between chelating agents and the metal alkoxide starting reagents) and film consolidation, densification, and crystallization.

  10. PZT Thin-Film Micro Probe Device with Dual Top Electrodes

    NASA Astrophysics Data System (ADS)

    Luo, Chuan

    Lead zirconate titanate (PZT) thin-film actuators have been studied intensively for years because of their potential applications in many fields. In this dissertation, a PZT thin-film micro probe device is designed, fabricated, studied, and proven to be acceptable as an intracochlear acoustic actuator. The micro probe device takes the form of a cantilever with a PZT thin-film diaphragm at the tip of the probe. The tip portion of the probe will be implanted in cochlea later in animal tests to prove its feasibility in hearing rehabilitation. The contribution of the dissertation is three-fold. First, a dual top electrodes design, consisting of a center electrode and an outer electrode, is developed to improve actuation displacement of the PZT thin-film diaphragm. The improvement by the dual top electrodes design is studied via a finite element model. When the dimensions of the dual electrodes are optimized, the displacement of the PZT thin-film diaphragm increases about 30%. A PZT thin-film diaphragm with dual top electrodes is fabricated to prove the concept, and experimental results confirm the predictions from the finite element analyses. Moreover, the dual electrode design can accommodate presence of significant residual stresses in the PZT thin-film diaphragm by changing the phase difference between the two electrodes. Second, a PZT thin-film micro probe device is fabricated and tested. The fabrication process consists of PZT thin-film deposition and deep reactive ion etching (DRIE). The uniqueness of the fabrication process is an automatic dicing mechanism that allows a large number of probes to be released easily from the wafer. Moreover, the fabrication is very efficient, because the DRIE process will form the PZT thin-film diaphragm and the special dicing mechanism simultaneously. After the probes are fabricated, they are tested with various possible implantation depths (i.e., boundary conditions). Experimental results show that future implantation depths should be less than 3 mm in order to guarantee the first resonant frequency above 60 kHz. Finally, a package for the PZT thin-film micro probe device is developed to ensure its proper function in an aqueous environment, such as inside of cochlea. The package is an insulation layer of parylene coating on the probe. A finite element analysis indicates that a coating thickness of less than 1 mum will reduce the PZT diaphragm displacement by less than 10%. A special fixture is designed to hold a large number of probes for parylene deposition of a thickness of 250 nm. A packaged probe is then submerged in deionized water and functions properly for at least 55 hours. Displacement and impedance of the probe are measured via a laser Doppler vibrometer and an impedance analyzer, respectively. Experimental results show that displacement of the PZT diaphragm increases about 30% in two hours, after the probe is submerged in the deionized water. The impedance measurement shows consistent trends. A hypothesis to explain this unusual phenomenon is diffusion of water molecules into the PZT thin film. High-resolution SEM images of the probe indicate presence of numerous nano-pores in the surface of the PZT thin film, indirectly confirming the hypothesis. Keywords: PZT, Thin-Film, Dual Electrodes, Parylene Coating, Aqueous Environment, Cochlear Implant

  11. Using PZT Grid Networks in Low Velocity Impact Studies

    NASA Astrophysics Data System (ADS)

    Carmona-Reyes, Jorge; Cook, Mike; Schmoke, Jimmy; Harper, Katie; Reay, Jerry; Matthews, Lorin; Hyde, Truell

    2004-10-01

    Orbital debris has become such a large problem that computer models, space debris tracking devices, and debris shielding processes have become a vital part of the preparation for the launch of any space mission. In order to fully understand the physics behind the damage that space debris may cause, it is first necessary to reproduce such an environment in the lab. The Center for Astrophysics, Space Physics and Engineering Research (CASPER) has completed construction and calibration of a Light Gas Gun (LGG) which is used for low velocity impact studies. The LGG was used to perform impact tests on stainless steel and aluminum disk plates, since these materials are often used in the construction of man-made structures in space. Piezoelectric lead zirconate titanate (PZT) crystals were employed to measure the momentum delivered to the plate upon impact. Multiple PZT networks were attached to the plates in order to determine the location of individual impacts. This paper will show the results of this testing on both stainless steel and aluminum disks and explain the numerical process determining the locations of the impacts.

  12. Interface magnetoelectric effect in the layered heterostructures with Co layers on the polished and ion-beam planarized ceramic PZT substrates

    NASA Astrophysics Data System (ADS)

    Stognij, Alexandre I.; Novitskii, Nickolaj; Poddubnaya, Natalia; Sharko, Sergei; Ketsko, Valerij; Mikhailov, Vladimir; Dyakonov, Vladimir; Szymczak, Henryk

    2015-01-01

    The low-frequency room temperature interface magnetoelectric (ME) effect was observed in the layered heterostructures comprising the ferromagnetic (FM) Co layers and ferroelectric (FE) ceramic substrates on the base of lead zirconate titanate PbZr0.45Ti0.55O3 (PZT). The Co films 1-12 ?m in thickness were deposited by ion-beam sputtering/deposition technics onto the 400 ?m PZT substrates. Results of X-ray, magnetic and ME experiments have shown the existence of ME effect in Co/PZT/Co and (Co/PZT/Co)3 heterostructures obtained by the above mentioned techniques being independent on ferromagnetic/ferroelectric interface roughness. The values of ME voltage coefficient in heterostructures with ion-beam planarized PZT surfaces are much higher than that in heterostructures with mechanochemically polished ceramic substrate surfaces. The heterostructures possess ME effect of the same order as those obtained by means of the mechanical bonding of FM and FE sheets with organic binders and have the typical ME hysteresis curves. The structures obtained are perspective for application as energy-independent elements in magnetic field sensors and magnetic memory.

  13. Lanthanide-Assisted Deposition of Strongly Electro-optic PZT Thin Films on Silicon: Toward Integrated Active Nanophotonic Devices.

    PubMed

    George, J P; Smet, P F; Botterman, J; Bliznuk, V; Woestenborghs, W; Van Thourhout, D; Neyts, K; Beeckman, J

    2015-06-24

    The electro-optical properties of lead zirconate titanate (PZT) thin films depend strongly on the quality and crystallographic orientation of the thin films. We demonstrate a novel method to grow highly textured PZT thin films on silicon using the chemical solution deposition (CSD) process. We report the use of ultrathin (5-15 nm) lanthanide (La, Pr, Nd, Sm) based intermediate layers for obtaining preferentially (100) oriented PZT thin films. X-ray diffraction measurements indicate preferentially oriented intermediate Ln2O2CO3 layers providing an excellent lattice match with the PZT thin films grown on top. The XRD and scanning electron microscopy measurements reveal that the annealed layers are dense, uniform, crack-free and highly oriented (>99.8%) without apparent defects or secondary phases. The EDX and HRTEM characterization confirm that the template layers act as an efficient diffusion barrier and form a sharp interface between the substrate and the PZT. The electrical measurements indicate a dielectric constant of ?650, low dielectric loss of ?0.02, coercive field of 70 kV/cm, remnant polarization of 25 ?C/cm(2), and large breakdown electric field of 1000 kV/cm. Finally, the effective electro-optic coefficients of the films are estimated with a spectroscopic ellipsometer measurement, considering the electric field induced variations in the phase reflectance ratio. The electro-optic measurements reveal excellent linear effective pockels coefficients of 110 to 240 pm/V, which makes the CSD deposited PZT thin film an ideal candidate for Si-based active integrated nanophotonic devices. PMID:26043103

  14. Photovoltaic enhancement due to surface-plasmon assisted visible-light absorption at the inartificial surface of lead zirconate-titanate film.

    PubMed

    Zheng, Fengang; Zhang, Peng; Wang, Xiaofeng; Huang, Wen; Zhang, Jinxing; Shen, Mingrong; Dong, Wen; Fang, Liang; Bai, Yongbin; Shen, Xiaoqing; Sun, Hua; Hao, Jianhua

    2014-03-01

    PZT film of 300 nm thickness was deposited on tin indium oxide (ITO) coated quartz by a sol-gel method. Four metal electrodes, such as Pt, Au, Cu and Ag, were used as top electrodes deposited on the same PZT film by sputtering at room temperature. In ITO-PZT-Ag and ITO-PZT-Au structures, the visible light (400-700 nm) can be absorbed partially by a PZT film, and the maximum efficiency of photoelectric conversion of the ITO-PZT-Ag structure was enhanced to 0.42% (100 mW cm(-2), AM 1.5G), which is about 15 times higher than that of the ITO-PZT-Pt structure. Numerical simulations show that the natural random roughness of polycrystalline-PZT-metal interface can offer a possibility of coupling between the incident photons and SPs at the metal surface. The coincidence between the calculated SP properties and the measured EQE spectra reveals the SP origin of the photovoltaic enhancement in these ITO-PZT-metal structures, and the improved photocurrent output is caused by the enhanced optical absorption in the PZT region near the metal surface, rather than by the direct charge-transfer process between two materials. PMID:24477668

  15. Investigations on structural and multiferroic properties of artificially engineered lead zirconate titanate-cobalt iron oxide layered nanostructures

    NASA Astrophysics Data System (ADS)

    Ortega Achury, Nora Patricia

    Mutiferroics are a novel class of next generation multifunctional materials, which display simultaneous magnetic, electric, and ferroelastic ordering, have drawn increasing interest due to their multi-functionality for a variety of device applications. Since, very rare single phase materials exist in nature this kind of properties, an intensive research activity is being pursued towards the development of new engineered materials with strong magneto-electric (ME) coupling. In the present investigation, we have fabricated polycrystalline and highly oriented PbZr0.53,Ti0.47O3--CoFe 2O4 (PZT/CFO) artificially multilayers (MLs) engineered nanostructures thin films which were grown on Pt/TiO2/SiO2/Si and La 0.5Sr0.5CoO3 (LSCO) coated (001) MgO substrates respectively, using the pulsed laser deposition technique. The effect of various PZT/CFO sandwich configurations having 3, 5, and 9 layers, while maintaining similar total PZT and CFO thickness, has been systematically investigated. The first part of this thesis is devoted to the analysis of structural and microstructure properties of the PZT/CFO MLs. X-ray diffraction (XRD) and micro Raman analysis revealed that PZT and CFO were in the perovskite and spinel phases respectively in the all layered nanostructure, without any intermediate phase. The TEM and STEM line scan of the ML thin films showed that the layered structure was maintained with little inter-diffusion near the interfaces at nano-metric scale without any impurity phase, however better interface was observed in highly oriented films. Second part of this dissertation was dedicated to study of the dielectric, impedance, modulus, and conductivity spectroscopies. These measurements were carried out over a wide range of temperatures (100 K to 600 K) and frequencies (100 Hz to 1 MHz) to investigate the grain and grain boundary effects on electrical properties of MLs. The temperature dependent dielectric and loss tangent illustrated step-like behavior and relaxation peaks near the step-up characteristic respectively. The Cole-Cole plots indicate that the most of the dielectric response came from the bulk (grains) MLs below 300 K, whereas grain boundaries and electrode-MLs effects prominent at elevated temperature. The dielectric loss relaxation peaks shifted to higher frequency side with increase in temperature, finally above 300 K, it went out experimental frequency window. Our Cole-Cole fitting of dielectric loss spectra indicated marked deviation from the ideal Debye type of relaxation which is more prominent at elevated temperature. Master modulus spectra support the observation from impedance spectra, it also indicate that the difference between C g and Cgb are higher compared to polycrystalline MLs indicating less effects of grain boundary in highly oriented MLs. We have explained these electrical properties of MLs by Maxwell-Wagner type contributions arising from the interfacial charge at the interface of the MLs structure. Three different types of frequency dependent conduction process were observed at elevated temperature (>300 K), which well fitted with the double power law, sigma(o) = sigma(0) + A 1on1 + A 2on2, it indicates conduction at: Low frequency (<1 kHz) may be due to long range ordering (frequency independent), mid frequency (<10 kHz) may be due to short range hopping, and high frequency (<1 MHz) due to the localized relaxation hopping mechanism. The last part of the thesis is devoted to the study of the multiferroic and magnetoelectric properties of the ML thin films. Both polycrystalline and highly oriented films showed well saturated ferroelectric and ferromagnetic hysteresis loops at room temperature. Temperature dependence of ferroelectric properties showed that polarization slowly decreases from 300 K to 200 K, with complete collapse of polarization at ˜ 100 K, but there was complete recovery of the polarization during heating, which was repeatable over many different experiments. At the same time, in the same temperature interval the remanent magnetization of the MLs showed slo

  16. Measurements of the thermal, dielectric, piezoelectric, pyroelectric and elastic properties of porous PZT samples

    NASA Astrophysics Data System (ADS)

    Lang, Sidney B.; Ringgaard, Erling

    2012-06-01

    The introduction of porosity into ferroelectric ceramics has been of great interest in recent years. In particular, studies of porous lead-zirconate-titanate ceramic (PZT) have been made. In the research reported, samples of Ferroperm Pz27 with porosities of 20, 25 and 30% were studied. Very complete measurements were made of all of the physical properties relevant for ferroelectric applications including thermal conductivity and diffusivity, heat capacity, dielectric, pyroelectric, piezoelectric and elastic properties. Scanning electron micrographs indicated a change from 3-0 to 3-3 connectivity with increasing porosity. Although most of the physical properties are degraded by the presence of porosity, both piezoelectric and pyroelectric figures-of-merit are improved because of the markedly reduced relative permittivity. Porous ferroelectric ceramics are very promising materials for a number of applications.

  17. Adjustable grazing incidence x-ray optics based on thin PZT films

    NASA Astrophysics Data System (ADS)

    Cotroneo, Vincenzo; Davis, William N.; Marquez, Vanessa; Reid, Paul B.; Schwartz, Daniel A.; Johnson-Wilke, Raegan L.; Trolier-McKinstry, Susan E.; Wilke, Rudeger H. T.

    2012-10-01

    The direct deposition of piezoelectric thin films on thin substrates offers an appealing technology for the realization of lightweight adjustable mirrors capable of sub-arcsecond resolution. This solution will make it possible to realize X-ray telescopes with both large effective area and exceptional angular resolution and, in particular, it will enable the realization of the adjustable optics for the proposed mission Square Meter Arcsecond Resolution X-ray Telescope (SMART-X). In the past years we demonstrated for the first time the possibility of depositing a working piezoelectric thin film (1-5 um) made of lead-zirconate-titanate (PZT) on glass. Here we review the recent progress in film deposition and influence function characterization and comparison with finite element models. The suitability of the deposited films is analyzed and some constrains on the piezoelectric film performances are derived. The future steps in the development of the technology are described.

  18. Synthesis and characterization of group IV metal adamantanol alkoxides as potential PZT precursors

    SciTech Connect

    Boyle, T.J.; Pearson, A.T.; Schwartz, R.W. [Sandia National Labs., Albuquerque, NM (United States)

    1994-12-31

    The size and morphology of adamantanol (AdamO-H) make it an interesting ligand to investigate as a possible starting reagent for the generation of lead zirconate titanate (PZT) thin films. It was believed that hydrolysis, due to ambient humidity, would be reduced as the steric bulk around the metal center was increased. Group IV (Ti, Zr) metal alkoxides were reacted, in sundry stoichiometries, with adamantanol and the resulting compounds were used for film generation. Surprisingly, most of these compounds crystallized when their solutions were spin-cast deposited onto silicon substrates. The one exception was the (AdamO)Zr(OCHMe{sub 2}){sub 3} compound, which apparently gelled. Ellipsometric data obtained on this film showed that typical densification occurred.

  19. Damage evaluation based on a wave energy flow map using multiple PZT sensors.

    PubMed

    Liu, Yaolu; Hu, Ning; Xu, Hong; Yuan, Weifeng; Yan, Cheng; Li, Yuan; Goda, Riu; Alamusi, Emptyyn Y; Qiu, Jinhao; Ning, Huiming; Wu, Liangke

    2014-01-01

    A new wave energy flow (WEF) map concept was proposed in this work. Based on it, an improved technique incorporating the laser scanning method and Betti's reciprocal theorem was developed to evaluate the shape and size of damage as well as to realize visualization of wave propagation. In this technique, a simple signal processing algorithm was proposed to construct the WEF map when waves propagate through an inspection region, and multiple lead zirconate titanate (PZT) sensors were employed to improve inspection reliability. Various damages in aluminum and carbon fiber reinforced plastic laminated plates were experimentally and numerically evaluated to validate this technique. The results show that it can effectively evaluate the shape and size of damage from wave field variations around the damage in the WEF map. PMID:24463430

  20. Large Stroke Vertical PZT Microactuator With High-Speed Rotational Scanning

    PubMed Central

    Qiu, Zhen; Rhee, Choong-Ho; Choi, Jongsoo; Wang, Thomas D.; Oldham, Kenn R.

    2014-01-01

    A thin-film piezoelectric microactuator using a novel combination of active vertical translational scanning and passive resonant rotational scanning is presented. Thin-film lead-zirconate-titanate unimorph bending beams surrounding a central platform provide nearly 200-?m displacement at 18 V with bandwidth greater than 200 Hz. Inside the platform, a mirror mount, or mirror surface, supported by silicon dioxide spring beams can be excited to resonance by low-voltage; high-frequency excitation of the outer PZT beams. Over ±5.5° mechanical resonance is obtained at 3.8 kHz and ±2 V. The combination of large translational vertical displacements and high-speed rotational scanning is intended to support real-time cross-sectional imaging in a dual axes confocal endomicroscope. PMID:25506187

  1. Fabrication and characterization of micromachined high-frequency tonpilz transducers derived by PZT thick films.

    PubMed

    Zhou, Qifa; Cannata, Jonathan M; Meyer, Richard J; van Tol, David J; Tadigadapa, Srinivas; Hughes, W Jack; Shung, K Kirk; Trolier-McKinstry, Susan

    2005-03-01

    Miniaturized tonpilz transducers are potentially useful for ultrasonic imaging in the 10 to 100 MHz frequency range due to their higher efficiency and output capabilities. In this work, 4 to 10-microm thick piezoelectric thin films were used as the active element in the construction of miniaturized tonpilz structures. The tonpilz stack consisted of silver/lead zirconate titanate (PZT)/lanthanum nickelate (LaNiO3)/silicon on insulator (SOI) substrates. First, conductive LaNiO3 thin films, approximately 300 nm in thickness, were grown on SOI substrates by a metalorganic decomposition (MOD) method. The room temperature resistivity of the LaNiO3 was 6.5 x 10(-6) omega x m. Randomly oriented PZT (52/48) films up to 7-microm thick were then deposited using a sol-gel process on the LaNiO3-coated SOI substrates. The PZT films with LaNiO3 bottom electrodes showed good dielectric and ferroelectric properties. The relative dielectric permittivity (at 1 kHz) was about 1030. The remanent polarization of PZT films was larger than 26 microC/cm2. The effective transverse piezoelectric e31,f coefficient of PZT thick films was about -6.5 C/m2 when poled at -75 kV/cm for 15 minutes at room temperature. Enhanced piezoelectric properties were obtained on poling the PZT films at higher temperatures. A silver layer about 40-microm thick was prepared by silver powder dispersed in epoxy and deposited onto the PZT film to form the tail mass of the tonpilz structure. The top layers of this wafer were subsequently diced with a saw, and the structure was bonded to a second wafer. The original silicon carrier wafer was polished and etched using a Xenon difluoride (XeF2) etching system. The resulting structures showed good piezoelectric activity. This process flow should enable integration of the piezoelectric elements with drive/receive electronics. PMID:15857042

  2. Development of dual PZT transducers for reference-free crack detection in thin plate structures.

    PubMed

    Sohn, Hoon; Kim, Seuno Bum

    2010-01-01

    A new Lamb-wave-based nondestructive testing (NDT) technique, which does not rely on previously stored baseline data, is developed for crack monitoring in plate structures. Commonly, the presence of damage is identified by comparing "current data" measured from a potentially damaged stage of a structure with "baseline data" previously obtained at the intact condition of the structure. In practice, structural defects typically take place long after collection of the baseline data, and the baseline data can be also affected by external loading, temperature variations, and changing boundary conditions. To eliminate the dependence on the baseline data comparison, the authors previously developed a reference-free NDT technique using 2 pairs of collocated lead zirconate titanate (PZT) transducers placed on both sides of a plate. This reference-free technique is further advanced in the present study by the necessity of attaching transducers only on a single surface of a structure for certain applications such as aircraft. To achieve this goal, a new design of PZT transducers called dual PZT transducers is proposed. Crack formation creates Lamb wave mode conversion due to a sudden thickness change of the structure. This crack appearance is instantly detected from the measured Lamb wave signals using the dual PZT transducers. This study also suggests a reference-free statistical approach that enables damage classification using only the currently measured data set. Numerical simulations and experiments were conducted using an aluminum plate with uniform thickness and fundamental Lamb waves modes to demonstrate the applicability of the proposed technique to reference-free crack detection. PMID:20040449

  3. PZT-based active damage detection techniques for steel bridge components

    NASA Astrophysics Data System (ADS)

    Park, Seunghee; Yun, Chung-Bang; Roh, Yongrae; Lee, Jong-Jae

    2006-08-01

    This paper presents the results of experimental studies on piezoelectric lead-zirconate-titanate (PZT)-based active damage detection techniques for nondestructive evaluations (NDE) of steel bridge components. PZT patches offer special features suitable for real-time in situ health monitoring systems for large and complex steel structures, because they are small, light, cheap, and useful as built-in sensor systems. Both impedance and Lamb wave methods are considered for damage detection of lab-size steel bridge members. Several damage-sensitive features are extracted: root mean square deviations (RMSD) in the impedances and wavelet coefficients (WC) of Lamb waves, and the times of flight (TOF) of Lamb waves. Advanced signal processing and pattern recognition techniques such as continuous wavelet transform (CWT) and support vector machine (SVM) are used in the current system. Firstly, PZT patches were used in conjunction with the impedance and Lamb waves to detect the presence and growth of artificial cracks on a 1/8 scale model for a vertical truss member of Seongsu Bridge, Seoul, Korea, which collapsed in 1994. The RMSD in the impedances and WC of Lamb waves were found to be good damage indicators. Secondly, two PZT patches were used to detect damage on a bolt-jointed steel plate, which was simulated by removing bolts. The correlation of the Lamb wave transmission data with the damage classified by in and out of the wave path was investigated by using the TOF and WC obtained from the Lamb wave signals. The SVM was implemented to enhance the damage identification capability of the current system. The results from the experiments showed the validity of the proposed methods.

  4. Enhancing the dielectric property of 0.69PZT-0.31PZNN thick films by optimizing the poling condition

    NASA Astrophysics Data System (ADS)

    Song, Daniel; Woo, Min Sik; Ahn, Jung Hwan; Sung, Tae Hyun

    2015-05-01

    We investigated how the applied electric-field's magnitude and the poling time affected, respectively, the dielectric property and the microstructure of piezoelectric lead zirconate titanate/lead zirconate nickel niobate (PZT-PZNN) thick films in order to apply the films to piezoelectric energy harvesters. Several 300-µm-thick, 10 × 10-mm2 PZT-PZNN squares were tape cast, laminated, sintered, and poled under 2-, 4-, 6-, 10-, 14-, and 15-kV/mm electric fields for 30 min. The 10-kV/mm electric field produced the highest d 33 × g 33 without mechanically damaging the sample. Further, samples were sintered at 950, 1000, and 1020 °C and subsequently poled at 10 kV/mm (previously determined as the magnitude of the optimal poling electric field) for 15, 30, 60, 120, and 240 min to investigate how the poling time affected the piezoelectric ceramic's microstructure. The optimal poling time for all the sintered samples was 60 min. Further, the piezoelectric ceramics composed of small grains and poled longer than 60 min showed higher dielectric constants. However, those composed of large grains and poled for times shorter than 60 min showed higher dielectric constants because the element mobility of the piezoelectric ceramics increased with increasing poling time.

  5. Real-time, label-free, all-electrical detection of Salmonella typhimurium using lead titanate zirconate\\/gold-coated glass cantilevers at any relative humidity

    Microsoft Academic Search

    Qing Zhu; Wan Y. Shih; Wei-Heng Shih

    2007-01-01

    We have examined non-insulated PZT\\/gold-coated glass cantilevers for real-time, label-free detection of Salmonella typhimurium by partial dipping at any relative humidity. The PZT\\/gold-coated glass cantilevers consisted of a 0.127mm-thick PZT layer about 0.8mm long, 2mm wide bonded to a 0.15mm-thick gold-coated glass layer with a 3.0mm-long gold-coated glass tip for detection. We showed that by placing the water level at

  6. Emission, plasma formation, and brightness of a PZT ferroelectric cathode

    SciTech Connect

    Sampayan, S.; Caporaso, G.; Trimble, D.; Westenskow, G.

    1995-04-27

    We have measured an 36-A-cm{sup {minus}2} current emission density over the surface area of an 11.4-cm{sup 2}-area Lead-Titanate- Zirconate (PZT) ferroelectric cathode with a pulsed anode-cathode (A-K) potential of 50 kV. We have also observed currents above those predicted by classical Child-Langmuir formula for a wide variety of cases. Since a plasma within the A-K gap could also lead to increase current emission we are attempting to measure the properties of the plasma near the cathode surface at emission time. In other measurements, we have observed strong gap currents in the absence of an A-K potential. Further, we continue to make brightness measurements of the emitted beam and observe spatially non-uniform emission and large shot-to-shot variation. Measurements show individual beamlets with a brightness as high 10{sup 11} Am{sup {minus}2} rad{sup {minus}2}.

  7. Powering low-power implants using PZT transducer discs operated in the radial mode

    NASA Astrophysics Data System (ADS)

    Sanni, Ayodele; Vilches, Antonio

    2013-11-01

    This paper reports experimental results that are used to compare operation characteristics of lead zirconate titanate (PZT) piezoelectric ceramic discs operated in the radial mode. The devices are driven to radially vibrate at their lowest fundamental resonant frequency and thus transmit and receive power when immersed in a liquid phantom. A number of 1 mm × 10 mm (thickness × diameter) PZT discs are characterized experimentally within a propagation tank and results discussed. On the basis of these measured characteristics, a novel application is developed and reported for the first time. This consists of a tuned LC resonator circuit which is used at the receiving disc to maximize sensitivity as well as a Seiko start-up IC S-882Z which is employed to charge a capacitor that drives a PIC microcontroller (?C) once the voltage exceeds 2 V DC. We show that a mean input power of 486 mW RMS results in 976 ?W RMS received over a range of 80 mm and that this is sufficient to periodically (every 60 s) power the ?C to directly drive a red LED for 5 ms with a current of 4.8 mA/flash. This approach is suitable for low-power, periodically activated analogue bio-implant applications.

  8. Direct strain energy harvesting in automobile tires using piezoelectric PZT-polymer composites

    NASA Astrophysics Data System (ADS)

    van den Ende, D. A.; van de Wiel, H. J.; Groen, W. A.; van der Zwaag, S.

    2012-01-01

    Direct piezoelectric strain energy harvesting can be used to power wireless autonomous sensors in environments where low frequency, high strains are present, such as in automobile tires during operation. However, these high strains place stringent demands on the materials with respect to mechanical failure or depolarization, especially at elevated temperatures. In this work, three kinds of ceramic-polymer composite piezoelectric materials were evaluated and compared against state-of-the-art piezoelectric materials. The new composites are unstructured and structured composites containing granular lead zirconate titanate (PZT) particles or PZT fibers in a polyurethane matrix. The composites were used to build energy harvesting patches which were attached to a tire and tested under simulated rolling conditions. The energy density of the piezoelectric ceramic-polymer composite materials is initially not as high as that of the reference materials (a macro-fiber composite and a polyvinylidene fluoride polymer). However, the area normalized power output of the composites after temperature and strain cycling is comparable to that of the reference devices because the piezoelectric ceramic-polymer composites did not degrade during operation.

  9. A PZT-based smart aggregate for seismic shear stress monitoring

    NASA Astrophysics Data System (ADS)

    Hou, S.; Zhang, H. B.; Ou, J. P.

    2013-06-01

    A lead zirconate titanate (PZT)-based smart aggregate (SA) is proposed for seismic shear stress monitoring in concrete structures. This SA uses a d15-mode PZT as the sensing element. A calibration test is designed in which a cyclic shear stress with a dominant frequency of the earthquake response spectrum is applied on the two opposite sides of the proposed SA using a specially designed loading mold. The test is repeated on six copies of the proposed SA. The maximum applied shear stress is larger than the shear strength of ordinary concrete to allow measurements during failure. The output voltage of the SA is experimentally verified as varying linearly with the applied stress in the loading range. The sensitivity of the proposed SA to the applied stress under the given boundary conditions is examined. The calibrated sensitivity value is then compared with the calculated value, which is obtained by computing the stress distribution in the SA using finite element analysis (FEA). The calculated values and the calibrated values are approximately the same, indicating that the established finite element (FE) model is reliable. Monotonic loading is also applied on the proposed SA to induce cracks between the SA and the loading mold, and the SA’s response to cracking processes is examined. It is found that the proposed SA underestimates the cracking process. This study demonstrates that the proposed SA can be used in monitoring the overall shear stress development process in concrete during a seismic event.

  10. Numerical analysis for structural health monitoring of a damaged composite panel using PZT actuators and sensors

    NASA Astrophysics Data System (ADS)

    Nagabhushana, A.; Spiegel, M.; Adu, S.; Hayes, N.; Paul, D.; Trivedi, K.; Fairbee, B.; Zheng, H.; Gerrity, A.; Kotru, S.; Roy, S.; Barkey, M.; Burkett, S. L.

    2012-04-01

    Reliable damage detection is crucial for assessing the integrity of a structure. In this paper, a numerical study of a composite panel fabricated to simulate a crack is undertaken using finite element methods (FEM). The damage to be considered is a transverse crack which pre-exists in the structure. The finite element models are developed for an undamaged and a damaged composite panel to compute the change in Lamb wave response due to the existence of a crack. The model is validated using shear lag analysis applied at the crack. The results are verified experimentally by comparing the results for an undamaged composite panel and a composite panel fabricated with a simulated crack using the vacuum assisted resin transfer molding (VARTM) process. The responses for each panel are obtained using surface mounted lead zirconate titanate (PZT) actuators and sensors. PZT is used to generate Lamb waves which produce stress throughout the panel thickness. Propagation characteristics of Lamb waves are varied by the presence of damage. The sensor data provide reliable information about the integrity of the structure. Numerical results are compared to the sensor output to ensure accuracy of the damage detection system.

  11. Real-Time, Label-Free, All-Electrical Detection of Salmonella typhimurium Using Lead Zirconate Titanate/Gold-Coated Glass Cantilevers at any Relative Humidity

    PubMed Central

    Zhu, Qing; Shih, Wan Y.; Shih, Wei-Heng

    2007-01-01

    We have examined non-insulated PZT/gold-coated glass cantilevers for real-time, label-free detection of Salmonella t. by partial dipping at any relative humidity. The PZT/gold-coated glass cantilevers were consisted of a 0.127 mm thick PZT layer about 0.8 mm long, 2 mm wide bonded to a 0.15 mm thick gold-coated glass layer with a 3.0 mm long gold-coated glass tip for detection. We showed that by placing the water level at the nodal point, about 0.8 mm from the free end of the gold-glass tip, there was a 1-hr window in which the resonance frequency was stable despite the water level change by evaporation at 20% relative humidity or higher. By dipping the cantilevers to their nodal point, we were able to do real-time, label-free detection without background resonance frequency corrections at any relative humidity. The partially dipped PZT/gold-coated glass cantilever exhibited mass detection sensitivity, ?m/?f = ?5×10?11g/Hz, and a detection concentration sensitivity, 5×103 cells/ml in 2 ml of liquid, which was about two orders of magnitude lower than that of a 5 MHz QCM. It was also about two orders of magnitude lower than the infection dosage and one order of magnitude lower that the detection limit of a commercial Raptor sensor. PMID:22872784

  12. Measurement of effective piezoelectric coefficients of PZT thin films for energy harvesting application with interdigitated electrodes.

    PubMed

    Chidambaram, Nachiappan; Mazzalai, Andrea; Muralt, Paul

    2012-08-01

    Interdigitated electrode (IDE) systems with lead zirconate titanate (PZT) thin films play an increasingly important role for two reasons: first, such a configuration generates higher voltages than parallel plate capacitor-type electrode (PPE) structures, and second, the application of an electric field leads to a compressive stress component in addition to the overall stress state, unlike a PPE structure, which results in tensile stress component. Because ceramics tend to crack at relatively moderate tensile stresses, this means that IDEs have a lower risk of cracking than PPEs. For these reasons, IDE systems are ideal for energy harvesting of vibration energy, and for actuators. Systematic investigations of PZT films with IDE systems have not yet been undertaken. In this work, we present results on the evaluation of the in-plane piezoelectric coefficients with IDE systems. Additionally, we also propose a simple and measurable figure of merit (FOM) to analyze and evaluate the relevant piezoelectric parameter for harvesting efficiency without the need to fabricate the energy harvesting device. Idealized effective coefficients e(IDE) and h(IDE) are derived, showing its composite nature with about one-third contribution of the transverse effect, and about two-thirds contribution of the longitudinal effect in the case of a PZT film deposited on a (100)-oriented silicon wafer with the in-plane electric field along one of the <011> Si directions. Randomly oriented 1-?m-thick PZT 53/47 film deposited by a sol-gel technique, was evaluated and yielded an effective coefficient e(IDE) of 15 C·m(-2). Our FOM is the product between effective e and h coefficient representing twice the electrical energy density stored in the piezoelectric film per unit strain deformation (both for IDE and PPE systems). Assuming homogeneous fields between the fingers, and neglecting the contribution from below the electrode fingers, the FOM for IDE structures with larger electrode gap is derived to be twice as large as for PPE structures, for PZT-5H properties. The experiments yielded an FOM of the IDE structures of 1.25 × 10(10) J/m(3) and 14 mV/? strain. PMID:22899110

  13. Quick response PZT/P(VDF-TrFE) composite film pyroelectric infrared sensor with patterned polyimide thermal isolation layer

    NASA Astrophysics Data System (ADS)

    Wu, C. G.; Li, P.; Cai, G. Q.; Luo, W. B.; Sun, X. Y.; Peng, Q. X.; Zhang, W. L.

    2014-09-01

    The fabrication method and the pyroelectric response of a single element infrared sensor based lead zirconate titanate (PZT) particles and polyvinylidene fluoride P(VDF-TrFE) copolymer composite thick film is reported in this paper. A special thermal insulation structure, including polyimide (PI) thermal insulation layer and thermal insulation tanks, was used in this device. The thermal insulation tanks were fabricated by laser micro-etching technique. Voltage responsivity (RV), noise voltage (Vnoise), noise equivalent power (NEP), and detectivity (D*) of the PZT/P(VDF-TrFE) based infrared sensor are 1.2 × 103 V/W, 1.25 × 10-6 V Hz1/2, 1.1 × 10-9 W and 1.9 × 108 cm Hz1/2 W-1 at 137.3 Hz modulation frequency, respectively. The thermal time constant of the infrared sensor ?T was about 15 ms. The results demonstrate that the composite infrared sensor show a high detectivity at high chopper frequency, which is an essential advantage in infrared detectors and some other devices.

  14. Local piezoelectric behavior in PZT-based thin films for ultrasound transducers

    NASA Astrophysics Data System (ADS)

    Griggio, Flavio

    Piezoelectric microelectromechanical systems (MEMS) are currently used in inkjet printers and precision resonators; numerous additional applications are being investigated for sensors, low-voltage actuators, and transducers. This work was aimed at improving piezoelectric MEMS by taking two approaches: 1) identifying factors affecting the piezoelectric response of ferroelectric thin films and 2) demonstrating integration of these films into a high frequency array transducer. It was found that there are several key factors influencing the piezoelectric response of thin films for a given material composition. First, large grain size improves the piezoelectric response. This was demonstrated using chemical solution deposited lead nickel niobate -- lead zirconate titanate (0.3)Pb(Ni 0.33Nb0.67)O3 - (0.7)Pb(Zr0.45Ti 0.55O3), (PNN-PZT) ferroelectric thin films. It was shown that this composition allows greater microstructural control than does PZT. Dielectric permittivities ranging from 1350 to 1520 and a transverse piezoelectric coefficient e31,f as high as -- 9.7 C/m 2 were observed for films of about 0.25 mum in thickness. The permittivity and piezoelectric response as well as extrinsic contributions to the dielectric constant increased by 14 and 12 % respectively for samples with grain sizes ranging from 110 to 270 nm. A second factor influencing the piezoelectric response is film composition with respect to the morphotropic phase boundary (MPB). The composition dependence of the dielectric and piezoelectric nonlinearities was characterized in epitaxially grown (0.3)Pb(Ni0.33Nb0.67)O3-(0.7)Pb(Zr xTi1-xO3) thin films deposited on SrTiO 3 to minimize the influence of large-angle grain boundaries. Tetragonal, MPB and rhombohedral films were prepared by changing the Zr/Ti ratio. The largest dielectric and piezoelectric nonlinearities were observed for the rhombohedral sample; this resulted from a higher domain wall mobility due to a smaller ferroelectric distortion and superior crystal quality. Thirdly, changes in the mechanical boundary conditions experienced by a ferroelectric thin film were found to influence both the properties and the length scale for correlated motion of domain walls. Microfabrication was employed to release the PZT films from the Si substrate. Nonlinear piezoelectric maps, by band excitation piezoforce microscopy, showed formation of clusters of higher nonlinear activities of similar size for clamped PZT films with different microstructures. However PZT films that had been released from the Si substrate showed a distinct increase in the correlation length associated with coupled domain wall motion, suggesting that the local mechanical boundary conditions, more than microstructure or composition govern the domain wall dynamics. Release of both the local and the global stress states in films produced dielectric nonlinearities comparable to those of bulk ceramics. The second research direction was targeted at demonstrating the functionality of a one dimensional transducer array. A diaphragm geometry was used for the transducer arrays in order to benefit from the unimorph-type displacement of the PZT-SiO2 layers. For this purpose, the PZT and remaining films in the stack were patterned using reactive ion etching and partially released from the underlying silicon substrate by XeF2 etching from the top. Admittance measurements on the fabricated structures showed resonance frequencies at ˜40 MHz for a 80 mum diameter-wide diaphragms with a PZT thickness of 1.74 mum. In-water transmit and receive functionalities were demonstrated. A bandwidth on receive of 80 % centered at 40 MHz was determined during pitch-mode tests.

  15. Fabrication and Characterization of PZT Thick Films for Sensing and Actuation

    PubMed Central

    Jang, Ling-Sheng; Kuo, Kuo-Ching

    2007-01-01

    Lead Zirconate Titanate oxide (PZT) thick films with thicknesses of up to 10 mm were developed using a modified sol-gel technique. Usually, the film thickness is less than 1 mm by conventional sol-gel processing, while the electrical charge accumulation which reveals the direct effect of piezoelectricity is proportional to the film thickness and therefore restricted. Two approaches were adopted to conventional sol-gel processing – precursor concentration modulation and rapid thermal annealing. A 10 ?m thick film was successfully fabricated by coating 16 times via this technique. The thickness of each coating layer was about 0.6 mm and the morphology of the film was dense with a crack-free area as large as 16 mm2. In addition, the structure, surface morphology and physical properties were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM) and atomic force microscopy (AFM) and electrical performance. The dielectric constant and hysteresis loops were measured as electric characteristics. This study investigates the actuation and sensing performance of the vibrating structures with the piezoelectric thick film. The actuation tests demonstrated that a 4 mm × 4 mm × 6.5 mm PZT film drove a 40 mm × 7 mm × 0.5 mm silicon beam as an actuator. Additionally, it generated an electrical signal of 60 mVpp as a sensor, while vibration was input by a shaker. The frequencies of the first two modes of the beam were compared with the theoretical values obtained by Euler-Bernoulli beam theory. The linearity of the actuation and sensing tests were also examined.

  16. Effects of electric field on the fracture toughness (KIc) of ceramic PZT

    NASA Astrophysics Data System (ADS)

    Goljahi, Sam; Lynch, Christopher S.

    2013-09-01

    This work was motivated by the observation that a small percentage of the ceramic lead zirconate titanate (PZT) parts in a device application, one that requires an electrode pattern on the PZT surface, developed fatigue cracks at the edges of the electrodes; yet all of the parts were subjected to similar loading. To obtain additional information on the fracture behavior of this material, similar specimens were run at higher voltage in the laboratory under a microscope to observe the initiation and growth of the fatigue cracks. A sequence of experiments was next performed to determine whether there were fracture toughness variations that depended on material processing. Plates were cut from a single bar in different locations and the Vickers indentation technique was used to measure the relative fracture toughness as a function of position along the bar. Small variations in toughness were found, that may account for some of the devices developing fatigue cracks and not others. Fracture toughness was measured next as a function of electric field. The surface crack in flexure technique was modified to apply an electric field perpendicular to a crack. The results indicate that the fracture toughness drops under a positive electric field and increases under a negative electric field that is less than the coercive field, but as the negative coercive field is approached the fracture toughness drops. Examination of the fracture surfaces using an optical microscope and a surface profilometer reveal the initial indentation crack shape and (although less accurately) the crack shape and size at the transition from stable to unstable growth. These results are discussed in terms of a ferroelastic toughening mechanism that is dependent on electric field.

  17. Array lead zirconate titanate/glass piezoelectric microcantilevers for real-time detection of Bacillus anthracis with 10 spores/ml sensitivity and 1/1000 selectivity in bacterial mixtures

    NASA Astrophysics Data System (ADS)

    McGovern, John-Paul; Shih, Wei-Heng; Rest, Richard F.; Purohit, Mitali; Mattiucci, Mark; Pourrezaei, Kambiz; Onaral, Banu; Shih, Wan Y.

    2009-12-01

    An array of three identical piezoelectric microcantilever sensors (PEMSs) consisting of a lead zirconate titanate layer bonded to a glass layer was fabricated and examined for simultaneous, in situ, real-time, all-electrical detection of Bacillus anthracis (BA) spores in an aqueous suspension using the first longitudinal extension mode of resonance. With anti-BA antibody immobilized on the sensor surfaces all three PEMS exhibited identical BA detection resonance frequency shifts at all tested concentrations, 10-107 spores/ml with a standard deviation of less than 10%. The detection concentration limit of 10 spores/ml was about two orders of magnitude lower than would be permitted by flexural peaks. In blinded-sample testing, the array PEMS detected BA in three samples containing BA: (1) 3.3×103 spores/ml, (2) a mixture of 3.3×103 spores/ml and 3.3×105 S. aureus (SA) and P. aeruginosa (PA) per ml, and (3) a mixture of 3.3×103 spores/ml with 3.3×106 SA+PA/ml. There was no response to a sample containing only 3.3×106 SA+PA/ml. These results illustrate the sensitivity, specificity, reusability, and reliability of array PEMS for in situ, real-time detection of BA spores.

  18. Sol-gel synthesis of high-quality SrRuO{sub 3} thin film electrodes suppressing the formation of detrimental RuO{sub 2} and the dielectric properties of integrated lead lanthanum zirconate titanate films.

    SciTech Connect

    Narayanan, M.; Tong, S.; Koritala, R.; Ma, B.; Pol, V.; Balachandran, U.

    2011-01-01

    A facile solution chemistry is demonstrated to fabricate high-quality polycrystalline strontium ruthenium oxide (SrRuO{sub 3}) thin film electrodes on silicon substrates suppressing the formation of undesired ruthenium oxide (RuO{sub 2}) for the deposition of dielectric and ferroelectric materials like lead lanthanum zirconate titanate (PLZT). The robust, highly crystalline SrRuO{sub 3} film fabrication process does not favor the formation of RuO{sub 2} because of molecular level modification of the precursors possessing analogous melting points, yielding homogeneous films. This chemistry is further understood and complemented by kinetic and thermodynamic analysis of the DTA data under nonisothermal conditions, with which the activation energies to form RuO{sub 2} and SrRuO{sub 3} were calculated to be 156 {+-} 17 and 96 {+-} 10 kJ/mol, respectively. The room-temperature resistivity of the SrRuO{sub 3} film was measured to be 850 {+-} 50 {mu}{Omega} cm on silicon (100) substrates. The dielectric properties of sol-gel-derived PLZT thin film capacitors on polycrystalline SrRuO{sub 3} electrodes were also measured to illustrate the high quality of the formed SrRuO{sub 3} bottom electrode. These results have broad implications for the expanded use of these conductive oxide electrodes in many applications that require low thermal budgets. The PLZT (8/52/48) films exhibited well-defined hysteresis loops with remanent polarization of {approx}10.5 {micro}C/cm{sup 2}, dielectric constant of >1450, dielectric loss of <0.06, and leakage current density of {approx}3.8 x 10{sup -8} A/cm{sup 2}. These dielectric properties are similar to those of PLZT on platinized silicon, indicating the high quality of the bottom conductive oxide layer. In addition, the PLZT capacitors were essentially fatigue free for >1 x 10{sup 9} cycles when deposited over an oxide electrode.

  19. A three-degree-of-freedom thin-film PZT-actuated microactuator with large out-of-plane displacement

    PubMed Central

    Choi, Jongsoo; Qiu, Zhen; Rhee, Choong-Ho; Wang, Thomas; Oldham, Kenn

    2014-01-01

    A novel three degree-of-freedom microactuator based on thin-film lead-zirconate-titanate (PZT) is described with its detailed structural model. Its central rectangular-shaped mirror platform, also referred to as the stage, is actuated by four symmetric PZT bending legs such that each leg provides vertical translation for one corner of the stage. It has been developed to support real-time in vivo vertical cross-sectional imaging with a dual axes confocal endomicroscope for early cancer detection, having large displacements in three axes (z, ?x, ?y) and a relatively high bandwidth in the z-axis direction. Prototype microactuators closely meet the performance requirements for this application; in the out-of-plane (z-axis) direction, it has shown more than 177 ?m of displacement and about 84 Hz of structural natural frequency, when two diagonal legs are actuated at 14V. With all four legs, another prototype of the same design with lighter stage mass has achieved more than 430 ?m of out-of-plane displacement at 15V and about 200 Hz of bandwidth. The former design has shown approximately 6.4° and 2.9° of stage tilting about the x-axis and y-axis, respectively, at 14V. This paper also presents a modeling technique that uses experimental data to account for the effects of fabrication uncertainties in residual stress and structural dimensions. The presented model predicts the static motion of the stage within an average absolute error of 14.6 ?m, which approaches the desired imaging resolution, 5 ?m, and also reasonably anticipates the structural dynamic behavior of the stage. The refined model will support development of a future trajectory tracking controller for the system. PMID:25506131

  20. Magnetoelectric effect in layered ferrite/PZT composites. Study of the demagnetizing effect on the magnetoelectric behavior

    NASA Astrophysics Data System (ADS)

    Loyau, V.; Morin, V.; Chaplier, G.; LoBue, M.; Mazaleyrat, F.

    2015-05-01

    We report the use of high magnetomechanical coupling ferrites in magnetoelectric (ME) layered composites. Bilayer samples combining (Ni0.973 Co0.027)1-xZnxFe2O4 ferrites (x = 0-0.5) synthesized by non conventional reactive Spark Plasma Sintering and commercial lead zirconate titanate (PZT) were characterized in term of ME voltage coefficients measured at sub-resonant frequency. Strong ME effects are obtained and we show that an annealing at 1000 °C and a quenching in air improve the piezomagnetic behavior of Zn-rich compositions. A theoretical model that predicts the ME behavior was developed, focusing our work on the demagnetizing effects in the transversal mode as well as the longitudinal mode. The model shows that: (i) high ME coefficients are obtained when ferrites with high magnetomechanical coupling are used in bilayer ME composites, (ii) the ME behavior in transversal and longitudinal modes is quite similar, and differences in the shapes of the ME curves are mainly due the demagnetizing effects, (iii) in the transversal mode, the magnetic field penetration depends on the ferrite layer thickness and the ME coefficient is affected accordingly. The two later points are confirmed by measurements on ME samples and calculations. Performances of the ME composites made with high magnetomechanical coupling ferrites are compared to those obtained using Terfenol-D materials in the same conditions of size, shape, and volume ratio. It appears that a ferrite with an optimized composition has performances comparable to those obtained with Terfenol-D material. Nevertheless, the fabrication processes of ferrites are quite simpler. Finally, a ferrite/PZT based ME composite was used as a current sensor.

  1. Chem-prep PZT 95/5 for neutron generator applicatios : powder preparation characterization utilizing design of experiments.

    SciTech Connect

    Lockwood, Steven John; Rodman-Gonzales, Emily Diane; Voigt, James A.; Moore, Diana Lynn

    2003-07-01

    Niobium doped PZT 95/5 (lead zirconate-lead titanate) is the material used in voltage bars for all ferroelectric neutron generator power supplies. In June of 1999, the transfer and scale-up of the Sandia Process from Department 1846 to Department 14192 was initiated. The laboratory-scale process of 1.6 kg has been successfully scaled to a production batch quantity of 10 kg. This report documents efforts to characterize and optimize the production-scale process utilizing Design of Experiments methodology. Of the 34 factors identified in the powder preparation sub-process, 11 were initially selected for the screening design. Additional experiments and safety analysis subsequently reduced the screening design to six factors. Three of the six factors (Milling Time, Media Size, and Pyrolysis Air Flow) were identified as statistically significant for one or more responses and were further investigated through a full factorial interaction design. Analysis of the interaction design resulted in developing models for Powder Bulk Density, Powder Tap Density, and +20 Mesh Fraction. Subsequent batches validated the models. The initial baseline powder preparation conditions were modified, resulting in improved powder yield by significantly reducing the +20 mesh waste fraction. Response variation analysis indicated additional investigation of the powder preparation sub-process steps was necessary to identify and reduce the sources of variation to further optimize the process.

  2. High performance Au/PZT/TiOxNy/Si MFIS structure for next generation ferroelectric memory applications

    NASA Astrophysics Data System (ADS)

    Sharma, Deepak K.; Khosla, Robin; Sharma, Satinder K.

    2015-05-01

    The Metal-Ferroelectric-Insulator-Semiconductor (MFIS) capacitors with thin 20 nm lead zirconate titanate (PZT) and titanium oxynitride (TiOxNy) buffer layer were fabricated by RF magnetron sputtering technique and characterized. TiOxNy as a buffer layer deposited for the first time for MFIS application at different thicknesses and fabricated structure was found to exhibit excellent electrical characteristics at 14 nm TiOxNy. Memory window of 0.4 V was found at low sweep voltage of ± 3 V which increases to 1.8 V at sweep voltage of ±14 V indicating multilevel data storage. Moreover the fabricated structure possesses low leakage current density of ˜4 µA/cm2 at 36 nm TiOxNy which increases to 12 µA/cm2 at 4 nm TiOxNy at 5 V, reasonable limit. Furthermore, the fabricated structure possesses outstanding data retention capability at 14 nm TiOxNy; the high and low capacitance becomes constant after few seconds and clearly distinguishable for 1h and 30 min. This shows that proposed MFIS structure is suitable for high performance ferroelectric memory applications.

  3. A large-scan-angle piezoelectric MEMS optical scanner actuated by a Nb-doped PZT thin film

    NASA Astrophysics Data System (ADS)

    Naono, Takayuki; Fujii, Takamichi; Esashi, Masayoshi; Tanaka, Shuji

    2014-01-01

    Resonant 1D microelectromechanical systems (MEMS) optical scanners actuated by piezoelectric unimorph actuators with a Nb-doped lead zirconate titanate (PNZT) thin film were developed for endoscopic optical coherence tomography (OCT) application. The MEMS scanners were designed as the resonance frequency was less than 125 Hz to obtain enough pixels per frame in OCT images. The device size was within 3.4 mm × 2.5 mm, which is compact enough to be installed in a side-imaging probe with 4 mm inner diameter. The fabrication process started with a silicon-on-insulator wafer, followed by PNZT deposition by the Rf sputtering and Si bulk micromachining process. The fabricated MEMS scanners showed maximum optical scan angles of 146° at 90 Hz, 148° at 124 Hz, 162° at 180 Hz, and 152° at 394 Hz at resonance in atmospheric pressure. Such wide scan angles were obtained by a drive voltage below 1.3 Vpp, ensuring intrinsic safety in in vivo uses. The scanner with the unpoled PNZT film showed three times as large a scan angle as that with a poled PZT films. A swept-source OCT system was constructed using the fabricated MEMS scanner, and cross-sectional images of a fingertip with image widths of 4.6 and 2.3 mm were acquired. In addition, a PNZT-based angle sensor was studied for feedback operation.

  4. Titan Meteorology

    NASA Astrophysics Data System (ADS)

    Mitchell, Jonathan

    2012-04-01

    Titan’s methane clouds have received much attention since they were first discovered spectroscopically (Griffith et al. 1998). Titan's seasons evolve slowly, and there is growing evidence of a seasonal response in the regions of methane cloud formation (e.g. Rodriguez et al. 2009). A complete, three-dimensional view of Titan’s clouds is possible through the determination of cloud-top heights from Cassini images (e.g., Ádámkovics et al. 2010). Even though Titan’s surface is warmed by very little sunlight, we now know Titan’s methane clouds are convective, evolving through tens of kilometers of altitude on timescales of hours to days with dynamics similar to clouds that appear on Earth (Porco et al. 2005). Cassini ISS has also shown evidence of rain storms on Titan that produce surface accumulation of methane (Turtle et al. 2009). Most recently, Cassini has revealed a 1000-km-scale, arrow-shaped cloud at the equator followed by changes that appear to be evidence of surface precipitation (Turtle et al. 2011b). Individual convective towers simulated with high fidelity indicate that surface convergence of methane humidity and dynamic lifting are required to trigger deep, precipitating convection (e.g. Barth & Rafkin 2010). The global expanses of these cloud outbursts, the evidence for surface precipitation, and the requirement of dynamic convergence and lifting at the surface to trigger deep convection motivate an analysis of storm formation in the context of Titan’s global circulation. I will review our current understanding of Titan’s methane meteorology using Cassini and ground-based observations and, in particular, global circulation model simulations of Titan’s methane cycle. When compared with cloud observations, our simulations indicate an essential role for planetary-scale atmospheric waves in organizing convective storms on large scales (Mitchell et al. 2011). I will end with predictions of Titan’s weather during the upcoming northern hemisphere summer.

  5. Scalable synthesis of morphotropic phase boundary lead zirconium titanate nanowires for energy harvesting.

    PubMed

    Zhou, Zhi; Tang, Haixiong; Sodano, Henry A

    2014-12-01

    Lead zirconium titanate (PZT) nanowires are synthesized using a scalable two-step hydrothermal reaction. The piezo-electric coupling coefficient of the PZT NWs shows the highest value for PZT nano-wires in the literature (80 ± 5 pm/V). A PZT-NW-based nanocomposite is fabri-cated to demonstrate an energy-harvesting application with an open-circuit voltage up to 7 V and a power density up to 2.4 ?W/cm(3) . PMID:25312483

  6. Effects of Microstructural Variables on the Shock Wave Response of PZT 95/5

    SciTech Connect

    SETCHELL, ROBERT E.; TUTTLE, BRUCE A.; VOIGT, JAMES A.

    2003-02-01

    The particular lead zirconate/titanate composition PZT 95/5-2Nb was identified many years ago as a promising ferroelectric ceramic for use in shock-driven pulsed power supplies. The bulk density and the corresponding porous microstructure of this material can be varied by adding different types and quantities of organic pore formers prior to bisque firing and sintering. Early studies showed that the porous microstructure could have a significant effect on power supply performance, with only a relatively narrow range of densities providing acceptable shock wave response. However, relatively few studies were performed over the years to characterize the shock response of this material, yielding few insights on how microstructural features actually influence the constitutive mechanical, electrical, and phase-transition properties. The goal of the current work was to address these issues through comparative shock wave experiments on PZT 95/5-2Nb materials having different porous microstructures. A gas-gun facility was used to generate uniaxial-strain shock waves in test materials under carefully controlled impact conditions. Reverse-impact experiments were conducted to obtain basic Hugoniot data, and transmitted-wave experiments were conducted to examine both constitutive mechanical properties and shock-driven electrical currents. The present work benefited from a recent study in which a baseline material with a particular microstructure had been examined in detail. This study identified a complex mechanical behavior governed by anomalous compressibility and incomplete phase transformation at low shock amplitudes, and by a relatively slow yielding process at high shock amplitudes. Depoling currents are reduced at low shock stresses due to the incomplete transformation, and are reduced further in the presence of a strong electrical field. At high shock stresses, depoling currents are driven by a wave structure governed by the threshold for dynamic yielding. This wave structure is insensitive to the final wave amplitude, resulting in depoling currents that do not increase with shock amplitude for stresses above the yield threshold. In the present study, experiments were conducted under matched experimental conditions to directly compare with the behavior of the baseline material. Only subtle differences were observed in the mechanical and electrical shock responses of common-density materials having different porous microstructures, but large effects were observed when initial density was varied.

  7. An Automatic PZT with Prolonged Exposure

    NASA Astrophysics Data System (ADS)

    Hu, Q. Q.; Guo, R. H.; Liu, M. H.; Xu, Q. G.

    An automatic PZT with prolonged exposure was completed and put into operation at Wuchang Time Observatory of IGG of China in 1986. It is the second PZT designed and made in China, but it is rather different from the first one which is regarded as a traditional PZT. The main characteristics of this PZT are reported here.

  8. Three-dimensional BEM for piezoelectric fracture analysis J.A. Sanz, M.P. Ariza, J. Dominguez*

    E-print Network

    Ariza Moreno, Pilar

    loading conditions are analysed. Numerical solutions computed for prismatic cracked 3D plate problems structures. Lead zirconate titanate (PZT) is the most widely used piezoceramic and polyvinylidene fluoride

  9. Control of crystallographic texture and surface morphology of Pt/Tio2 templates for enhanced PZT thin film texture.

    PubMed

    Fox, Austin J; Drawl, Bill; Fox, Glen R; Gibbons, Brady J; Trolier-McKinstry, Susan

    2015-01-01

    Optimized processing conditions for Pt/TiO2/SiO2/Si templating electrodes were investigated. These electrodes are used to obtain [111] textured thin film lead zirconate titanate (Pb[ZrxTi1-x ]O3 0 ? x ? 1) (PZT). Titanium deposited by dc magnetron sputtering yields [0001] texture on a thermally oxidized Si wafer. It was found that by optimizing deposition time, pressure, power, and the chamber pre-conditioning, the Ti texture could be maximized while maintaining low surface roughness. When oxidized, titanium yields [100]-oriented rutile. This seed layer has as low as a 4.6% lattice mismatch with [111] Pt; thus, it is possible to achieve strongly oriented [111] Pt. The quality of the orientation and surface roughness of the TiO2 and the Ti directly affect the achievable Pt texture and surface morphology. A transition between optimal crystallographic texture and the smoothest templating surface occurs at approximately 30 nm of original Ti thickness (45 nm TiO2). This corresponds to 0.5 nm (2 nm for TiO2) rms roughness as determined by atomic force microscopy and a full-width at half-maximum (FWHM) of the rocking curve 0002 (200) peak of 5.5/spl degrees/ (3.1/spl degrees/ for TiO2). A Pb[Zr0.52Ti 0.48]O3 layer was deposited and shown to template from the textured Pt electrode, with a maximum [111] Lotgering factor of 87% and a minimum 111 FWHM of 2.4/spl degrees/ at approximately 30 nm of original Ti. PMID:25585390

  10. Role of macrodefects in PZT thin films for microelectromechanical systems

    SciTech Connect

    Cooney, T.G.; Hachfeld, E.A.; Francis, L.F. [Univ. of Minnesota, Minneapolis, MN (United States)

    1994-12-31

    Sol-gel derived lead zirconate titanate thin films were deposited on Si/SiO{sub 2}/Ti/Pt substrates which had varying surface roughness ({approximately}40-100 {angstrom} RMS) and contained larger features with varying vertical relief (0.1 - 0.6 {mu}m). The incidence of cracking increased as the surface roughness increased. Cracks initiated at the corners of rectangular surface features; macrodefects were more severe on narrow surface features and those with larger height and when more sol layers were deposited. To avoid defects, changes in the sol composition and device design are suggested.

  11. http://journals.cambridge.org Downloaded: 25 Jul 2013 IP address: 129.2.129.152 Optimization of PbTiO3 seed layers and Pt metallization

    E-print Network

    Rubloff, Gary W.

    the entire MEMS industry through the launch of the Nintendo Wii gaming console that uses 3D MEMS accel past research results on lead zirconate titanate (PZT) using the fabrication processes at the U.S. Army used in this study, lead zirconate titanate [Pb(Zrx Ti1Àx)O3, PZT] whose properties have been stud- ied

  12. IOP PUBLISHING JOURNAL OF PHYSICS: CONDENSED MATTER J. Phys.: Condens. Matter 20 (2008) 425206 (4pp) doi:10.1088/0953-8984/20/42/425206

    E-print Network

    Srinivasan, Gopalan

    2008-01-01

    coupling was reported for a system free of a free of any substrate, i.e., cobalt ferrite on BTO [5 ferrite on lead zirconate titanate (PZT). Both ideal and non-ideal interface coupling are considered so far include ferrite, metals or alloys for the magnetic phase and lead zirconate titanate (PZT

  13. Characterizing Titan's Upper Atmosphere Using the Titan

    E-print Network

    Johnson, Robert E.

    Characterizing Titan's Upper Atmosphere Using the Titan Global Ionosphere-Thermosphere Model Jared the Thermosphere · We model the upper atmosphere from 500 km up to 1500 km. · Use the Titan Global Ionosphere, Titan (and now Jupiter and Saturn). ­ Details in Ridley et al. [2006], Bell et al. [2010a, 2010b

  14. Pb diffusion in zircon

    Microsoft Academic Search

    D. J Cherniak; E. B Watson

    2001-01-01

    Diffusion of Pb was characterized in natural and synthetic zircon under a range of conditions. In most experiments, mixtures of Pb sulfate and ground zircon were used as the sources of diffusant, with Pb depth profiles measured with Rutherford Backscattering Spectrometry (RBS). As complement to these “in-diffusion” experiments, “out-diffusion” experiments were run on both synthetic Pb-doped and natural zircon with

  15. RMS TITANIC

    NSDL National Science Digital Library

    Miss Law

    2010-04-20

    You will be exploring the R.M.S Titanic. This includes an individual passenger, the class system on board, the collision and warnings leading up to it, and the construction of the ship. Hi Hillside Third Graders! Welcome to the Titanic... To watch some videos of the Wreck click on this link below. Scroll down and click on the yellow link above the YouTube screen that says watch more videos. Use the left side of the screen to help you find the word "Wreck Videos". Watch three ...

  16. Ceramic with zircon coating

    NASA Technical Reports Server (NTRS)

    Wang, Hongyu (Inventor)

    2003-01-01

    An article comprises a silicon-containing substrate and a zircon coating. The article can comprise a silicon carbide/silicon (SiC/Si) substrate, a zircon (ZrSiO.sub.4) intermediate coating and an external environmental/thermal barrier coating.

  17. Improvement of the dielectric breakdown strength and leakage currents of nano-sized CFO PZT particulate composite thin film with high particle loadings by controlled percolation for magnetoelectric applications

    NASA Astrophysics Data System (ADS)

    Muchenik Cena, Tomas Ignacio

    Magnetic and electric properties of a nano-sized particulate composite thin film consisting of non-percolating 11 nm superparamagnetic CoFe2O4 (CFO, Cobalt Ferrite) particles dispersed in a pure perovskite Pb[Zr 0.52Ti0.48]O3 (PZT, Lead Zirconate Titanate) matrix have been studied. The main objective of the study was to fabricate a composite with high particle loading conserving good dielectric breakdown strength (DBS) and leakage currents, which are commonly decreased at high loadings levels due to percolation. In this work, a composite with 38 vol% particulate loading showing no sign of percolation was prepared and characterized by DBS, leakage and polarization measurements. This improvement is explained with an analytical model proposed by Kusy, where percolation is increased when the diameter of the particulates is larger than the diameter of the matrix precursor. As a result of this, the leakage currents measurements, at 667 kV/cm, indicated an increase from 3*10--6 to 6 *10--5 A/cm2 ( 5 *10--10 and 9 *10--9 S/m ) for the samples with 1 and 38 vol% particulate loading, respectively, that remains lower than the leakage current of the PZT thin film, 6* 10--3A/cm2 (9 * 10--7 S/m), due to the reduction in crystallite size and grain orientation. No percolation was observed by the DBS characterization either, the increase of conductive CFO particles from 1 to 38 vol% decreased the DBS from 1800 kV/cm to 1200 kV/cm, respectively, which is still considerably higher than the DBS of the PZT thin film, 700 kV/cm, due to same reasons. Moreover, the behavior of the DBS for different particulate loadings is explained by an non-percolative analytical model consisting in the grain size effect and reduction of the effective film thickness given by the conductive phase, showing a good fit to the experimental data. This is in contrast to previously reported particulate composites, with magnetic and electric properties, that show percolation for low amounts of particulate loadings destroying the electric properties of the ferroelectric phase. The design proposed in this work is of great interest for the fabrication of films with high magnetic particulate loadings without degrading the electric properties for magnetoelectric applications.

  18. Molecular Structure of Zircon

    NSDL National Science Digital Library

    2002-09-06

    Zircon (zirconium silicate) was found in Greece and Italy as far back as the 6th Century A.D. Zircon comes from the Persian word "zargun" which means gold-colored. Zircon has been used as a diamond substitute because it resembles diamond in luster and has been mistaken for diamonds by many experienced jewelers, although it is not the same as Cubic Zirconia. It can be brown, red, green, blue, yellow, black, violet, orange and colorless. A typical crystal of zircon is shaped like a tetragonal prism with four sided prisms at each end. Zircon can be found in Laacher Sea, Niedermendig and Germany, and is mined in Cambodia, Sri Lanka, Thailand, Myanmar, Australia, and other countries.

  19. Zircons are Forever

    NSDL National Science Digital Library

    Zircons have been in the news lately because of the recent discovery that the chemical signature of the oldest known zircon crystal (4.4 billion years) suggests that water, and thus conditions for life on Earth, was present then. Geologists at the University of Wisconsin-Madison contributed to a large part of this study. Zircons are Forever is a newly posted feature page on the UW Geology and Geophysics Website. The text describes the basic chemistry of zircon and why it is an important mineral for studies of mantle formation. Particular emphasis is on stable isotope geochemistry. A hyperlinked bibliography leads to abstracts and plots of oxygen isotope values from papers by UW faculty and graduate students. Zircons are Forever adds a little more background to the recent headlines.

  20. Radiation Effects in Zircon

    SciTech Connect

    Ewing, Rodney C.; Meldrum, Alkiviathes; Wang, L. M.; Weber, William J.; Corrales, Louis R.

    2003-12-11

    The widespread distribution of zircon in the continental crust, its tendency to concentrate trace elements, particularly lanthanides and actinides, its use in age-dating, and its resistance to chemical and physical degradation have made zircon the most important accessory mineral in geologic studies. Because zircon is highly refractory, it also has important industrial applications, including its use as a lining material in high-temperature furnaces. However, during the past decade, zircon has also been proposed for advanced technology applications, such as a durable material for the immobilization of plutonium or, when modified by ion-beam irradiation, as an optic waveguide material. In all of these applications, the change in properties as a function of increasing radiation dose is of critical importance. In this chapter, we summarize the state-of-knowledge on the radiation damage accumulation process in zircon.

  1. Modified lead titanate thin films for pyroelectric infrared detectors on gold electrodes

    NASA Astrophysics Data System (ADS)

    Ahmed, Moinuddin; Butler, Donald P.

    2015-07-01

    Pyroelectric infrared detectors provide the advantage of both a wide spectral response and dynamic range, which also has enabled systems to be developed with reduced size, weight and power consumption. This paper demonstrates the deposition of lead zirconium titanate (PZT) and lead calcium titanate (PCT) thin films for uncooled pyroelectric detectors with the utilization of gold electrodes. The modified lead titanate thin films were deposited by pulsed laser deposition on gold electrodes. The PZT and PCT thins films deposited and annealed at temperatures of 650 °C and 550 °C respectively demonstrated the best pyroelectric performance in this work. The thin films displayed a pyroelectric effect that increased with temperature. Poling of the thin films was carried out for a fixed time periods and fixed dc bias voltages at elevated temperature in order to increase the pyroelectric coefficient by establishing a spontaneous polarization of the thin films. Poling caused the pyroelectric current to increase one order of magnitude.

  2. Titanic Research Link

    NSDL National Science Digital Library

    Miss Law

    2012-01-17

    Welcome Aboard the Titanic Third Graders! Enjoy your trip into the history of a fatal night. Use the following websites to help answer your research questions: Encyclopedia Titanica Construction Construction Begins Iceberg Inside the RMS Titanic RMS Titanic Inc.-The ShipThe CollisionThe Lure and the LoveTitanic FAQs ...

  3. ORNL debuts Titan supercomputer

    E-print Network

    Pennycook, Steve

    SCIENCE ORNL debuts Titan supercomputer ORNL has completed the installation of Titan--by employing a family of processors called graphic processing units first created for computer gaming. Titan and space limitations inherent in the previous generation of high- performance computers. Titan, which

  4. Chemical durability of zircon

    NASA Astrophysics Data System (ADS)

    Trocellier, Patrick; Delmas, Robert

    2001-07-01

    Zircon (ZrSiO 4) exhibits a strong structural affinity for uranium and thorium together with a very high chemical durability. This makes it a potential crystalline host matrix to immobilize actinides issued from separation of nuclear wastes. Irradiation induces amorphization of the crystalline structure (the metamictization process) and thus may decrease the chemical durability of the material. Leaching tests have been conducted on natural zircons from Brazil and Madagascar at 96°C for a period of 1 month, using deionized water. Leachates have been analysed by inductively coupled plasma mass spectrometry (ICP-MS) and UV-visible spectrophotometry. Zircon solid surfaces have been investigated by coupling scanning electron microscopy and X-ray microanalysis (SEM-EDX) with nuclear microprobe analysis ( ?PIXE, ?RBS and ?ERDA). From the mass balance between leachates and hydrated surfaces, the probable mechanisms of zircon aqueous alteration are presented and discussed.

  5. Titan Recreation-Titan Bowl and Billiards Student Engagement Report

    E-print Network

    de Lijser, Peter

    Titan Recreation-Titan Bowl and Billiards Student Engagement Report FY 2012-2013 Purpose Statement Titan Recreation strives to enhance participant experiences at CSUF through providing quality physical fitness and overall wellness. Titan Recreation also provides opportunities for cooperative

  6. Titan Recreation-Titan Bowl and Billiards Student Engagement Report

    E-print Network

    de Lijser, Peter

    Titan Recreation-Titan Bowl and Billiards Student Engagement Report FY 2010-2011 Purpose Statement Titan Recreation strives to enhance participant experiences at CSUF through providing quality physical fitness and overall wellness. Titan Recreation also provides opportunities for cooperative

  7. Polarization characterization of PZT disks and of embedded PZT plates by thermal wave methods

    NASA Astrophysics Data System (ADS)

    Eydam, Agnes; Suchaneck, Gunnar; Esslinger, Sophia; Schönecker, Andreas; Neumeister, Peter; Gerlach, Gerald

    2014-11-01

    In this work, the thermal wave method was applied to characterize PZT disks and embedded PZT plates with regard to the polarization magnitude and spatial homogeneity. The samples were exposed to periodic heating by means of a laser beam and the pyroelectric response was determined. Thermal relaxation times (single time constants or distributions of time constants) describe the heat losses of the PZT samples to the environment. The resulting pyroelectric current spectrum was fitted to the superposition of thermal relaxation processes. The pyroelectric coefficient gives insight in the polarization distribution. For PZT disks, the polarization distribution in the surface region showed a characteristic decrease towards the electrodes.

  8. Preparation and piezoelectric properties of textured PZT ceramics using PZT nano fibers

    Microsoft Academic Search

    Cai-feng Chen; Xiao-li Han; Jun Liu; Zhi-dan Ding

    2011-01-01

    PZT nano piezoelectric fibers were prepared by hydrothermal-template method. The effects of some reaction conditions on preparation were investigated, such as PH value, reaction temperature and time. The optimal hydrothermal conditions for preparing PZT nano fibers are that pH value is 13, reaction temperature is 190 °C, hydrothermal reactor filling degree is 60 %–70 %, reaction time is 10h, and

  9. Titan 2D: Understanding Titan’s Seasonal Atmospheric Cycles

    NASA Astrophysics Data System (ADS)

    Wong, Michael; Zhang, X.; Li, C.; Hu, R.; Shia, R.; Newman, C.; Müller-Wodarg, I.; Yung, Y.

    2013-10-01

    In this study, we present results from a novel two-dimensional (2D) model that simulates the physics and chemistry of Titan’s atmosphere. Despite being an icy moon of Saturn, Titan is the only Solar System object aside from Earth that is sheathed by a thick nitrogen-dominated atmosphere. This vulnerable gaseous envelope—an embodiment of a delicate coupling between photochemistry, radiation, and dynamics—is Nature’s laboratory for the synthesis of complex organic molecules. Titan’s large obliquity generates pronounced seasonal cycles in its atmosphere, and the Cassini spacecraft has been observing these variations since 2004. In particular, Cassini measurements show that the latitudinal distribution of Titan’s rich mélange of hydrocarbon species follows seasonal patterns. The mixing ratios of hydrocarbons increase with latitude towards the winter pole, suggesting a pole-to-pole circulation that reverses after equinox. Using a one-dimensional photochemical model of Titan’s atmosphere, we show that photochemistry alone cannot produce the observed meridional hydrocarbon distribution. This necessitates the employment of a 2D chemistry-transport model that includes meridional circulation as well as diffusive processes and photochemistry. Of additional concern, no previous 2D model of Titan extends beyond 500 km altitude—a critical limitation since the peak of methane photolysis is at 800 km. Our 2D model is the first to include Titan’s stratosphere, mesosphere, and thermosphere. The meridional circulation in our 2D model is derived from the outputs of two general circulation models (GCMs): the TitanWRF GCM (Newman et al. 2011) covering the troposphere, stratosphere, and lower mesosphere, and a thermosphere general circulation model (TGCM) covering the remainder of the atmosphere through the thermosphere (Müller-Wodarg et al. 2003; 2008). This presentation will focus on the utilization of these advances applied to the 2D Caltech/JPL KINETICS model to understand the seasonal and meridional distribution of hydrocarbons as well as other atmospheric cycles on Titan.

  10. Li diffusion in zircon

    Microsoft Academic Search

    D. J. CherniakE; E. B. Watson

    2010-01-01

    Diffusion of Li under anhydrous conditions at 1 atm and under fluid-present elevated pressure (1.0–1.2 GPa) conditions has\\u000a been measured in natural zircon. The source of diffusant for 1-atm experiments was ground natural spodumene, which was sealed\\u000a under vacuum in silica glass capsules with polished slabs of zircon. An experiment using a Dy-bearing source was also conducted\\u000a to evaluate possible rate-limiting effects

  11. Titanic: A Statistical Exploration.

    ERIC Educational Resources Information Center

    Takis, Sandra L.

    1999-01-01

    Uses the available data about the Titanic's passengers to interest students in exploring categorical data and the chi-square distribution. Describes activities incorporated into a statistics class and gives additional resources for collecting information about the Titanic. (ASK)

  12. Does Titan have oceans?

    NASA Astrophysics Data System (ADS)

    Lunine, J. I.

    1994-04-01

    Titan is one of the few worlds in the solar system whose essential nature remains hidden. Satellite data from Voyager are examined. Remote sensing investigations from Earth are explored. Possible models of Titan's surface are reviewed. A closer look at Titan would provide useful information. The data to be gathered by the planetary mission Cassini is discussed.

  13. Your Impact. Titan Pride?

    E-print Network

    de Lijser, Peter

    Your Gift. Your Impact. How Do You Show Your Titan Pride? Cal State Fullerton Department of Intercollegiate Athletics/Titan Athletics Club 800 North State College Boulevard Fullerton,California 92834-6810 657-278-4407 / FAX 657-278-8085 Your Titan Athletics. www.fullerton.edu/tac #12;Your Gift. The choice

  14. Titan Haze

    NASA Technical Reports Server (NTRS)

    Anderson, Carrie M.; West, Robert; Lavvas, Panayotis

    2011-01-01

    The Titan haze exerts a dominating influence on surface visibility and atmospheric radiative heating at optical and near-infrared wavelengths and our desire to understand surface composition and atmospheric dynamics provides a strong motivation to study the properties of the haze. Prior to the Cassini/Huygens missions the haze was known to be global in extent, with a hemispheric contrast asymmetry, with a complicated structure in the polar vortex region poleward of about 55 deg latitude, and with a distinct layer near 370 km altitude outside of the polar vortex at the time of the Voyager 2 flyby. The haze particles measured by the Pioneer and Voyager spacecraft were both highly polarizing and strongly forward scattering, a combination that seems to require an aggregation of small (several tens of nm radius) primary particles. These same properties were seen in the Cassini orbiter and Huygens Probe data. The most extensive set of optical measurements were made inside the atmosphere by the Descent Imager/Spectral Radiometer (DISR) instrument on the Huygens Probe. At the probe location as determined by the DISR measurements the average haze particle contained about 3000 primary particles whose radius is about 40 nm. Three distinct vertical regions were seen in the DISR data with differing particle properties. Refractive indices of the particles in the main haze layer resemble those reported by Khare et al. between O.3S and about 0.7 micron but are more absorbing than the Khare et al. results between 0.7 micron and the long-wavelength limit of the DISR spectra at 1.6 micron. These and other results are described by Tomasko et al., and a broader summary of results was given by Tomasko and West,. New data continue to stream in from the Cassini spacecraft. New data analyses and new laboratory and model results continue to move the field forward. Titan's 'detached' haze layer suffered a dramatic drop in altitude near equinox in 2009 with implications for the circulation and seasonal change in the stratosphere. The book chapter associated with this talk will also present new material on thermal-infrared data analysis and on new developments in laboratory work and haze microphysical modeling.

  15. FIXED POINTS OF ZIRCON AUTOMORPHISMS AXEL HULTMAN

    E-print Network

    Hultman, Axel

    FIXED POINTS OF ZIRCON AUTOMORPHISMS AXEL HULTMAN Abstract. A zircon is a poset in which every induced by the fixed points of any automorphism of a zircon is itself a zircon. This provides a natural.2. A poset P is a zircon if for any non-minimal element x P, the subposet induced by the principal order

  16. Interior of Titan

    NASA Technical Reports Server (NTRS)

    Stevenson, David J.

    1992-01-01

    General principles of Titan formation and evolution are addressed. Attention is focused on the volatile reservoir (defined as all constituents more volatile than water) of Titan's interior. Volatile poor models, in which Titan is like Granymede or Callisto with a thin (observed) volatile veneer are discussed and discarded. Volatile rich models in which the present Titan consists of a methane clathrate shell overlying a deep water ammonia ocean and solid ammonia hydrate are discussed. Titan has a central core of rock which is about one half of the total mass, and a superficial hydrocarbon 'ocean' stored in subsurface caverns and pore space.

  17. Two-dimensional microscanner actuated by PZT thin film

    Microsoft Academic Search

    Wen-Mei Lin; Andreas Schroth; Sohei Matsumoto; Chengkuo Lee; Ryutaro Maeda

    1999-01-01

    This paper introduces the fabrication and characterization of 2D resonant microscanners actuated by sol-gel deposited PZT thin films. The piezoelectric PZT thin films with silicon micromachining technology provide the advantages of high scanning frequencies and low driving voltages. The actuation principle is based on the bimorph beam structure, which consists of an oxide layer and a piezoelectric PZT layer. The

  18. Modeling, Optimization, and Design of Efficient Initially Curved Piezoceramic Unimorphs for Energy Harvesting Applications

    Microsoft Academic Search

    Hwan-Sik Yoon; Gregory Washington; Amita Danak

    2005-01-01

    The piezoceramic, lead zirconate titanate (PZT), is capable of producing large voltages with relatively minimal currents in response to an applied mechanical load when employed in initially curved laminates. This study addresses the issue of optimizing design parameters of a curved PZT unimorph to maximize charge generation due to mechanical loading. A horizontally placed PZT unimorph structure generates surface charge

  19. Zircon and granite petrology

    Microsoft Academic Search

    J. P. Pupin

    1980-01-01

    The typologic study of zircon populations from granitic rocks lead to the proposition of a genetic classification with three main divisions: (1) granites of crustal or mainly crustal origin [(sub) autochthonous and aluminous granites)]; (2) granites of crustal+mantle origin, hybrid granites (calc-alkaline and sub-alkaline series granites); (3) granites of mantle or mainly mantle origin (alkaline and tholeiitic series granites). In

  20. Isotopic Exchange in Igneous Zircons

    NASA Astrophysics Data System (ADS)

    Weaver, K. L.; Depaolo, D. J.

    2007-12-01

    Igneous zircons are a powerful tool for determining crystallization age and metamorphic history of rocks spanning Earth's entire geologic history. High concentrations of uranium and exclusion of lead in zircons make the U-Pb system the primary choice for radiogenic dating. This system has the added advantage of revealing potential parent or daughter loss as discordance on a concordia diagram. For a single mineral grain the U-Pb system reveals not only the age, but an estimate of post-crystallization alteration. As the range of isotopic analyses applied to ancient zircons broadens (oxygen isotopes, Lu-Hf), the ability to evaluate mobility in radiogenic systems other than U-Pb becomes more important. Low concentrations of many trace elements in zircon make them sensitive recorders of post-crystallization isotopic exchange, but their behavior is poorly understood. Comparison of the Sr- and Nd-isotopic systematics of zircon and its host rock can be used to evaluate the retentivity of zircon for the isotopes of these elements . We examined zircon populations from granitoids ranging in age from 100 Ma to 3.7 Ga. Zircon populations were dated via SHRIMP and both multigrain zircon separates and whole rock powders were analyzed for trace element concentrations, 87Sr/86Sr and 143Nd/144Nd. Analyses of other mineral separates (feldspar, apatite) allow the construction of whole- rock mineral isochrons. In each sample the zircons display disturbance in both the Rb-Sr and Sm-Nd systems. In fact, when compared to the all the other minerals represented on the isochron, the zircons display the highest amount of discordance. Likely promoted by radiation damage, the degree of open-system behavior of the Rb-Sr and Sm-Nd systems increases with the age of the samples. With greatly increased effective diffusivities and trace element mobility, general acceptance of zircons as impervious isotopic time capsules should be regarded with caution.

  1. From Titan’s tholins to Titan’s aerosols: Isotopic study and chemical evolution at Titan’s surface

    NASA Astrophysics Data System (ADS)

    Nguyen, Mai-Julie; Raulin, François; Coll, Patrice; Derenne, Sylvie; Szopa, Cyril; Cernogora, Guy; Israël, Guy; Bernard, Jean-Michel

    2008-07-01

    In the present work, we focused on the possible isotopic fractionation of carbon during the processes involved in the formation of Titan’s tholins. We present the first results obtained on the 12C/13C isotopic ratios measured on Titan’s tholins synthesized in laboratory with cold plasma discharges. Measurements of isotopic ratio 12C/13C, done both on tholins and on the initial gas mixture (N2:CH4 (98:2)) used to produce them, do not show any evident deficit or enrichment in 13C relatively to 12C in the synthesized tholins, compared to the initial gas mixture. This observation allows to go further in the analyses of the ACP experiment data, including part of the Cassini Huygens mission. We also focused on the chemical evolution of the aerosols at Titan surface by studying species coming from acid hydrolysis treatment of Titan’s tholins. Preliminary results show a wide diversity of chemical families, going from carboxylic acids to amino acids. Advanced studies could bring at short-term clues on the still unidentified mixture that induces the decrease of the reflectivity as measure by the DISR instrument [Tomasko, M.G., Archinal, B., Becker, T., Bézard, B., Bushroe, M., Combes, M., Cook, D., Coustenis, A., de Bergh, C., Dafoe, L.E., Doose, L., Douté, S., Eibl, A., Engel, S., Gliem, F., Grieger, B., Holso, K., Howington-Kraus, E., Karkoschka, E., Keller, H.U., Kirk, R., Kramm, R., Küppers, M., Lanagan, P., Lellouch, E., Lemmon, M., Lunine, J., McFarlane, E., Moores, J., Prout, G.M., Rizk, B., Rosiek, M., Rueffer, P., Schröder, S.E., Schmitt, B., See, C., Smith, P., Soderblom, L., Thomas, N., West, R. Rain, winds and haze during the Huygens probe’s descent to Titan’s surface. Nature 438(7069), 765 778, 2005]. At longer-term it could allow to better understand the possible chemical evolution of the Titan’s aerosols after falling down at the surface when brought into contact with water.

  2. Future Exploration of Titan

    NASA Astrophysics Data System (ADS)

    Lorenz, R. D.; Titan Decadal Panel Collaboration

    2001-11-01

    Titan promises to be the Mars of the Outer Solar System - the focus of not only the broadest range of investigations in planetary science but also the focus of public attention. The reasons for exploring Titan are threefold: 1. Titan and Astrobiology : Titan ranks with Mars and Europa as a prime body for astrobiological study due to its abundant organics. Like Europa, it may well have a liquid water interior. 2. Titan - A world in its own right. Titan deserves study even only to put other satellites (its remarkably smaller Saturnian siblings, and its same-sized but volatile-poor Jovian counterparts) in context. The added dimension of an atmosphere makes Titan's origin and evolution particularly interesting. 3. Titan - an environmental laboratory for Earth. Titan will be an unrivalled place to investigate meteorological, oceanographical and other processes. Many of these (e.g. wave generation by wind) are only empirically parameterized - the very different physical parameters of the Titan environment will bring new insights to these phenomena. While Cassini-Huygens will dramatically boost our knowledge of Titan, it will likely only whet our appetite for more. The potential for prebiotic materials at various locations (in particular where liquid water has interacted with photochemical deposits) and the need to monitor Titan's meteorology favor future missions that may exploit Titan's unique thick-atmosphere, low-gravity environment - a mobile platform like an airship or helicopter, able to explore on global scales, but access the surface for in-situ chemical analysis and probe the interior by electromagnetic and seismic means. Such missions have dramatic potential to capture the public's imagination, on both sides of the Atlantic.

  3. Very High Frequency (Beyond 100 MHz) PZT Kerfless Linear Arrays

    PubMed Central

    Wu, Da-Wei; Zhou, Qifa; Geng, Xuecang; Liu, Chang-Geng; Djuth, Frank; Shung, K. Kirk

    2010-01-01

    This paper presents the design, fabrication, and measurements of very high frequency kerfless linear arrays prepared from PZT film and PZT bulk material. A 12-µm PZT thick film fabricated from PZT-5H powder/solution composite and a piece of 15-µm PZT-5H sheet were used to fabricate 32-element kerfless high-frequency linear arrays with photolithography. The PZT thick film was prepared by spin-coating of PZT sol-gel composite solution. The thin PZT-5H sheet sample was prepared by lapping a PZT-5H ceramic with a precision lapping machine. The measured results of the 2 arrays were compared. The PZT film array had a center frequency of 120 MHz, a bandwidth of 60% with a parylene matching layer, and an insertion loss of 41 dB. The PZT ceramic sheet array was found to have a center frequency of 128 MHz with a poorer bandwidth (40% with a parylene matching layer) but a better sensitivity (28 dB insertion loss). PMID:19942516

  4. FBG Based Voltage Measurement using PZT Modulation

    Microsoft Academic Search

    Yuan Yao; Benshun Yi

    2006-01-01

    This article proposes a new fiber Bragg grating (FBG) sensor for voltage measurement. Based on the theoretical analysis of the relationship between the PZT electrostriction displacement and the applied voltage, using the characteristic of the FBG measurement - the FBG wavelength drift can reflect the FBG radial strain, a FBG voltage sensor is designed and developed. When the DC exciting

  5. Saturn Moons Explorer: Titan

    NSDL National Science Digital Library

    Only now are we beginning to learn about Titan, one of Saturn's most intriguing and enigmatic moons. This particular site provides an overview of Titan, courtesy of NASA's Jet Propulsion Laboratory, located at the California Institute of Technology. After watching an introductory video segment about Titan, visitors can learn more in the "Quick Facts" section. The "Latest Images" area contains twelve of the latest images of Titan as captured by the Cassini spacecraft. Visitors should also not miss the "3D Globe" area, which contains an interactive rendering of Titan which allows visitors to visit a number of features on this moon, including an ice volcano, drainage channels, and "The Smile", the brightest spot on Titan's surface.

  6. Titan Saturn System Mission

    NASA Technical Reports Server (NTRS)

    Reh, Kim R.

    2009-01-01

    Titan is a high priority for exploration, as recommended by NASA's 2006 Solar System Exploration (SSE) Roadmap. NASA's 2003 National Research Council (NRC) Decadal Survey and ESA's Cosmic Vision Program Themes. Recent revolutionary Cassini-Huygens discoveries have dramatically escalated interest in Titan as the next scientific target in the outer solar system. This study demonstrates that an exciting Titan Saturn System Mission (TSSM) that explores two worlds of intense astrobiological interest can be initiated now as a single NASA/ESA collaboration.

  7. Change from 3D-Ising to Random Field-Ising-Model Criticality in a Uniaxial Relaxor Ferroelectric

    E-print Network

    Osnabrück, Universität

    Change from 3D-Ising to Random Field-Ising-Model Criticality in a Uniaxial Relaxor Ferroelectric T piezoelectric sensors or actuators, where ceramics of lead zirconate titanate (PZT) or lead lanthanum zirconate titanate (PLZT) are extensively used [3], to optical applications like phase conjugated mirrors, where

  8. Titanic: Discovery Channel

    NSDL National Science Digital Library

    RMS Titanic raised a 23- by 14-foot section of the Titanic's outer hull this week, and the Discovery Channel, who helped sponsor the expedition, will be webcasting live from the interior of the Titanic via robot cameras August 16 at 8:00 and 10:00 p.m. (Eastern Time). In addition to their live webcase, the Discovery Channel site (discussed in the December 5, 1997 issue of the Scout Report) features virtual reality tours of sections of the Titanic before and after its crash, quicktime videos of the expeditions, a computer animated simulation of the crash, and more.

  9. PZT Films Fabricated by Metal Organic Decomposition Method

    NASA Astrophysics Data System (ADS)

    Sobolev, Vladimir; Ishchuk, Valeriy

    2014-03-01

    High quality lead zirconate titanate films have been fabricated on different substrates by metal organic decomposition method and their ferroelectric properties have been investigated. Main attention was paid to studies of the influence of the buffer layer with conditional composition Pb1.3(Zr0.5Ti0.5) O3 on the properties of Pb(Zr0.5Ti0.5) O3 films fabricated on the polycrystalline titanium and platinum substrates. It is found that in the films on the Pt substrate (with or without the buffer layer) the dependencies of the remanent polarization and the coercivity field on the number of switching cycles do not manifest fatigue up to 109 cycles. The remanent polarization dependencies for films on the Ti substrate with the buffer layer containing an excess of PbO demonstrate an fundamentally new feature that consists of a remanent polarization increase after 108 switching cycles. The increase of remanent polarization is about 50% when the number of cycles approaches 1010, while the increase of the coercivity field is small. A monotonic increase of dielectric losses has been observed in all cases.

  10. A Low Cost Coarse/Fine Piezoelectrically Actuated Microgripper With Force Measurement

    E-print Network

    Boyer, Edmond

    functions. These components have complex 3D shapes. This is why new micromanipulation technologies must to the cantilever. The cantilever is made up of two PZT (lead zirconate titanate) layers equipped with electrodes

  11. MEDYNA 2013: 1st Euro-Mediterranean Conference on Structural Dynamics and Vibroacoustics

    E-print Network

    Boyer, Edmond

    of the system. We will present here a sensitivity analysis of a 3D cantilever beam controlled by a shunted the last thirty years, vibration control using piezoelectric materials such as lead zirconate titanate (PZT

  12. Etching fission tracks in zircons

    USGS Publications Warehouse

    Naeser, C.W.

    1969-01-01

    A new technique has been developed whereby fission tracks can be etched in zircon with a solution of sodium hydroxide at 220??C. Etching time varied between 15 minutes and 5 hours. Colored zircon required less etching time than the colorless varieties.

  13. Genetic Adaptive Control for PZT Actuators

    NASA Technical Reports Server (NTRS)

    Kim, Jeongwook; Stover, Shelley K.; Madisetti, Vijay K.

    1995-01-01

    A piezoelectric transducer (PZT) is capable of providing linear motion if controlled correctly and could provide a replacement for traditional heavy and large servo systems using motors. This paper focuses on a genetic model reference adaptive control technique (GMRAC) for a PZT which is moving a mirror where the goal is to keep the mirror velocity constant. Genetic Algorithms (GAs) are an integral part of the GMRAC technique acting as the search engine for an optimal PID controller. Two methods are suggested to control the actuator in this research. The first one is to change the PID parameters and the other is to add an additional reference input in the system. The simulation results of these two methods are compared. Simulated Annealing (SA) is also used to solve the problem. Simulation results of GAs and SA are compared after simulation. GAs show the best result according to the simulation results. The entire model is designed using the Mathworks' Simulink tool.

  14. Titan's surface before Cassini

    Microsoft Academic Search

    Ralph D. Lorenz; Jonathan I. Lunine

    2005-01-01

    We review current understanding of Titan's surface, synthesizing a paradigm from Earth-based radar observations and near-infrared surface maps, together with reanalysis of Voyager data and results from published theoretical models. Based on these we suggest that Titan has a varied landscape with a variety of tectonic and erosive features indicative of geologic activity, and an impact crater population reflective of

  15. Cassini Titan Radar Mapper

    Microsoft Academic Search

    CHARLES ELACHI; E. Im; L. E. Roth; C. L. Werner

    1991-01-01

    The Cassini Titan Radar Mapper is a multimode radar instrument designed to probe the optically inaccessible surface of Titan, Saturn's largest moon. The instrument is to be included in the payload of the Cassini Saturn Mission, scheduled for launch in 1995. The individual modes of Cassini Radar Mapper will allow topographic mapping and surface imaging at few hundred meters resolution.

  16. PZT thin films grown by laser ablation

    Microsoft Academic Search

    Tupac Garcia; E. de Posada; Ernesto Jimenez; F. Calderon; P. Bartolo-Perez; J. L. Pena

    1999-01-01

    PZT thin films were deposited by laser ablation at high vacuum and at room temperature. After that, some of the samples were annealed at air in the temperature range 450 degree(s)C - 550 degree(s)C. The samples were characterized by XPS and X-ray diffraction. A decrease in the oxygen composition of the as-deposited sample was observed. In the as-deposited film metallic

  17. Titan's Methane Weather

    NASA Astrophysics Data System (ADS)

    Roe, Henry G.

    2012-05-01

    Conditions in Titan's troposphere are near the triple point of methane, the second most abundant component of its atmosphere. Our understanding of Titan's lower atmosphere has shifted considerably in the past decade. Ground-based observations, Hubble Space Telescope images, and data returned from the Cassini and Huygens spacecraft show that Titan's troposphere hosts a methane-based meteorology in direct analogy to the water-based meteorology of Earth. What once was thought to be a quiescent place, lacking in clouds or localized weather and changing only subtly on long seasonal timescales, is now understood to be a dynamic system with significant weather events regularly occurring against the backdrop of dramatic seasonal changes. Although the observational record of Titan's weather covers only a third of its 30-year seasonal cycle, Titan's atmospheric processes appear to be more closely analogous to those of Earth than to those of any other object in our solar system.

  18. The evolution of the Titan rocket - Titan I to Titan II

    NASA Astrophysics Data System (ADS)

    Adams, Laurence J.

    1990-10-01

    The Titan I and Titan II rockets are described. The designs of the stages, test stands, and basing systems are considered, and the developmental history of each rocket is briefly recapitulated. The ways in which Titan II represents an evolution from Titan I are pointed out.

  19. Aerosol growth in Titan’s ionosphere

    PubMed Central

    Lavvas, Panayotis; Yelle, Roger V.; Koskinen, Tommi; Bazin, Axel; Vuitton, Véronique; Vigren, Erik; Galand, Marina; Wellbrock, Anne; Coates, Andrew J.; Wahlund, Jan-Erik; Crary, Frank J.; Snowden, Darci

    2013-01-01

    Photochemically produced aerosols are common among the atmospheres of our solar system and beyond. Observations and models have shown that photochemical aerosols have direct consequences on atmospheric properties as well as important astrobiological ramifications, but the mechanisms involved in their formation remain unclear. Here we show that the formation of aerosols in Titan’s upper atmosphere is directly related to ion processes, and we provide a complete interpretation of observed mass spectra by the Cassini instruments from small to large masses. Because all planetary atmospheres possess ionospheres, we anticipate that the mechanisms identified here will be efficient in other environments as well, modulated by the chemical complexity of each atmosphere. PMID:23382231

  20. Dielectric and ferroelectric analysis of nanoparticle/nanocrystalline barium titanate and PLZT.

    SciTech Connect

    DiAntonio, Christopher Brian; Yang, Pin; Chavez, Tom P.; Winter, Michael R.; Monson, Todd C.; Roesler, Alexander William

    2010-07-01

    Attractive for numerous technological applications, ferroelectronic oxides constitute an important class of multifunctional compounds. Intense experimental efforts have been made recently in synthesizing, processing and understanding ferroelectric nanostructures. This work will present the systematic characterization and optimization of barium titanate and lead lanthanum zirconate titanate nanoparticle based ceramics. The nanoparticles have been synthesized using several solution and pH-based synthesis processing routes and employed to fabricate polycrystalline ceramic and nanocomposite based components. The dielectric and ferroelectric properties of these various components have been gauged by impedance analysis and electromechanical response and will be discussed.

  1. Titan's organic chemistry

    NASA Technical Reports Server (NTRS)

    Sagan, C.; Thompson, W. R.; Khare, B. N.

    1985-01-01

    Voyager discovered nine simple organic molecules in the atmosphere of Titan. Complex organic solids, called tholins, produced by irradiation of the simulated Titanian atmosphere, are consistent with measured properties of Titan from ultraviolet to microwave frequencies and are the likely main constituents of the observed red aerosols. The tholins contain many of the organic building blocks central to life on earth. At least 100-m, and possibly kms thicknesses of complex organics have been produced on Titan during the age of the solar system, and may exist today as submarine deposits beneath an extensive ocean of simple hydrocarbons.

  2. The TITAN reversed-field-pinch fusion reactor study

    SciTech Connect

    Not Available

    1990-01-01

    This report discusses the following topics: overview of titan-2 design; titan-2 fusion-power-core engineering; titan-2 divertor engineering; titan-2 tritium systems; titan-2 safety design and radioactive-waste disposal; and titan-2 maintenance procedures.

  3. Effect of Niobium Modifications to PZT (53\\/47) Thin Films Made by a Sol-Gel Route

    Microsoft Academic Search

    Rajnish Kurchania; Steven J. Milne

    2003-01-01

    Niobium-modified lead zirconate titanate thin films (PNZT) with nominal compositions, Pb(1-0.5x) (Zr0.53 Ti0.47)1-x NbxO3:x = 0.02–0.07, have been prepared using a diol based sol-gel route. Single-layer (0.5 µm) films were fabricated on platinised silicon substrates by spin-coating. The effect of niobium additions with regard to phase development, microstructure, and ferroelectric and dielectric properties were investigated for different annealing temperatures. For

  4. Raising the Titanic.

    ERIC Educational Resources Information Center

    Baker, Romona

    1990-01-01

    Described is an activity in which groups of students investigate engineering principles by writing a feasibility study to raise the luxury liner, Titanic. The problem statement and directions, and suggestions for problem solutions are included. (CW)

  5. Titan - Some new results

    NASA Astrophysics Data System (ADS)

    Owen, T.; Gautier, D.

    New analyses of Voyager spectra of Titan have led to improvements in the determination of abundances of minor constituents as a function of latitude and altitude. Ground-based microwave observations have extended the Voyager results for HCN, and have demonstrated that CO is mysteriously deficient in the stratosphere. The origin of the CH4, CO, and N2 in Titan's atmosphere is still unresolved. Both primordial and evolutionary sources are compatible with the available evidence.

  6. Titan's Ammonia Feature

    NASA Technical Reports Server (NTRS)

    Smythe, W.; Nelson, R.; Boryta, M.; Choukroun, M.

    2011-01-01

    NH3 has long been considered an important component in the formation and evolution of the outer planet satellites. NH3 is particularly important for Titan, since it may serve as the reservoir for atmospheric nitrogen. A brightening seen on Titan starting in 2004 may arise from a transient low-lying fog or surface coating of ammonia. The spectral shape suggests the ammonia is anhydrous, a molecule that hydrates quickly in the presence of water.

  7. Recrystallisation of oscillatory zoned zircon: some geochronological and petrological implications

    Microsoft Academic Search

    R. T. Pidgeon

    1992-01-01

    Oscillatory zoning is a common feature in zircons from acid igneous rocks and is believed to form during crystallisation of zircons from a magma by a mechanism which is not yet understood. Many zircons with oscillatory zoning also show a patchwork replacement of zoned by unzoned zircon. The unzoned zircon occurs as rounded, transgressive patches distributed throughout the zoned zircon

  8. Zircons from kimberlite: New insights from oxygen isotopes, trace elements, and Ti in zircon thermometry

    Microsoft Academic Search

    F. Zeb Page; Bin Fu; Noriko T. Kita; John Fournelle; Michael J. Spicuzza; Daniel J. Schulze; Fanus Viljoen; Miguel A. S. Basei; John W. Valley

    2007-01-01

    Zircons found in mantle-sourced kimberlite provide probes into the isotopic chemistry of the asthenosphere and subcontinental lithospheric mantle. However, little is known about the conditions of formation of these zircons. A suite of 88 zircons found in kimberlites from Africa, Siberia, Brazil, and the United States have been analyzed for their Ti concentration and selected zircons were analyzed for their

  9. Neutron Scattering Study of Single Crystal PZT

    NASA Astrophysics Data System (ADS)

    Phelan, Daniel; Gehring, Peter; Ye, Zuo-Guang; Long, Xifa

    2010-03-01

    Single crystal specimens of the technologically important ferroelectric material Pb(Zr1-xTix)O3, or PZT, have only recently been grown for the first time at Simon Fraser University. We have characterized the transition temperatures, thermal expansion, and crystal structure of a PZT single crystal between 10 K and 670 K using neutron scattering methods. This crystal, which has a composition (x˜0.46) that lies close to the morphotropic phase boundary (MPB), exhibits a surprisingly large thermal expansion (˜ 10-3 1/K) that changes sign near 545 K, and a rhombohedral crystal structure at 30 K. In addition we observe an enormous relief of extinction beginning around 650 K, which was observed through the temperature dependence of the (200) Bragg peak. Neutron inelastic measurements are planned as are measurements under an applied electric field. This work was supported by the U. S. Office of Naval Research (Grant No. N00014-1-06-0166). All neutron measurements were performed at the NIST Center for Neutron Research.

  10. Titan’s atmosphere from ISO mid-infrared spectroscopy

    Microsoft Academic Search

    Athena Coustenis; A. Salama; B. Schulz; S. Ott; E. Lellouch; T. h Encrenaz; D. Gautier; H. Feuchtgruber

    2003-01-01

    We have analyzed Titan observations performed by the Infrared Space Observatory (ISO) in the range 7–30 ?m. The spectra obtained by three of the instruments on board the mission (the short wavelength spectrometer, the photometer, and the camera) were combined to provide new and more precise thermal and compositional knowledge of Titan’s stratosphere. With the high spectral resolution achieved by

  11. Electrical imprint effects on far infrared (FIR) transmittance spectrum in PZT ferroelectric films

    NASA Astrophysics Data System (ADS)

    Vivas C., H.

    2015-06-01

    Tunable transmittance response in the 0.1-25 THz range for a lead Zirconate Titanate Ferroelectric film under imprint effects and surface anisotropy is calculated by adapting the classical Landau Devonshire theory and Rouard's method. Induced electrical field is introduced by modulating the P - E polarization profile, while the dielectric permittivity frequency dependence enters into the formalism by taking into account the soft phonon mode E(TO1) contribution in the framework of the Drude-Lorentz model. It is found that two optical states of light transmittance emerge at zero applied field and normal incidence, and the intensities of transmitted light are closely correlated with the strength of imprint and the path of the electrical polarization.

  12. Titan's impact history

    NASA Astrophysics Data System (ADS)

    Zahnle, Kevin

    2010-04-01

    Impacts play a major role in the growth and evolution of planets, satellites, and other nameless things. Titan is no exception. This talk will address a subset of the following topics: (i) The modern impact rate is constrained by the population of Centaurs and the impact rate at Jupiter. (ii) Titan's thick atmosphere and volatile surface cause it to respond to major impacts in an Earth-like manner. The impact that made Menrva - the 440 km diameter impact basin sited near the current apex of Titan's motion - was big enough to raise the average global surface temperature above 273 K, which suggests that water rain was possible. This would have been followed by methane drizzles lasting for thousands of years. More modest impacts will generate crater lakes and will saturate the atmosphere with methane, the latter leading to hundreds of years of intermittent drizzle. (iii) Impact ejecta from Menrva will strike Hyperion and should saturate the latter with sesquinary craters. (iv) In any modern story of how Titan got its atmosphere, solar nebular condensates (comets) deliver the volatiles. A consequence of a cometogenic atmosphere is that the atmosphere is heavily processed by strong shocks. The high temperatures produce a wide range of chemical species that would not otherwise be abundant. Some of these will survive to mix into the atmosphere (e.g., CO) or freeze out to fall to the surface (e.g. CO2). (v) That Titan even has an atmosphere, when Callisto and Ganymede do not, is an excellent question. The leading explanation is that Titan alone was made from ammonia - and methane - rich stuff. But the competition between impact delivery and impact expulsion of volatiles can strongly favor Titan over Callisto. Stable isotopes as well as total volatile inventories provide constraints.

  13. Crystallization thermometers for zircon and rutile

    Microsoft Academic Search

    E. B. Watson; D. A. Wark; J. B. Thomas

    2006-01-01

    Zircon and rutile are common accessory minerals whose essential structural constituents, Zr, Ti, and Si can replace one another to a limited extent. Here we present the combined results of high pressure-temperature experiments and analyses of natural zircons and rutile crystals that reveal systematic changes with temperature in the uptake of Ti in zircon and Zr in rutile. Detailed calibrations

  14. Crystallization thermometers for zircon and rutile

    Microsoft Academic Search

    E. B. Watson; D. A. Wark; J. B. Thomas

    2006-01-01

    Zircon and rutile are common accessory minerals whose essential structural constituents, Zr, Ti, and Si can replace one another to a limited extent. Here we present the combined results of high pressure–temperature experiments and analyses of natural zircons and rutile crystals that reveal systematic changes with temperature in the uptake of Ti in zircon and Zr in rutile. Detailed calibrations

  15. The Titan Graphics Supercomputer Architecture

    Microsoft Academic Search

    Tom Diede; Carl F. Hagenmaier; Glen S. Miranker; Jonathan J. Rubinstein; William S. Worley Jr.

    1988-01-01

    The design criteria for the Titan are outlined, and the hardware, architecture, and implementation developed to meet them are examined. The key architectural elements in Titan are described, and the reasoning behind their selection is presented. Titan's processor subsystem is explored, focusing on how it reduces the cost and complexity of graphics-specific hardware. The design constraints and implementation of the

  16. Methane ocean on Titan?

    NASA Astrophysics Data System (ADS)

    Bell, Peter M.

    There was an impressive list of names on a recent scientific communication that argues for the existence on Titan of an ocean of liquid methane (CH4) perhaps several hundred meters deep. C. Sagan and S. Dermott with helpful comments by S. Oter, S. Ostro, S. Peale, C. Yoder, W. Thompson, S. Squyres, G. Pettengill, P. Gierasch, and B. Khare speculate that such a methanic ocean, with its Saturnian tides and its tholinian floor, should exist all over Titan's surface; it should unless, they conclude, there is the ‘distracting coincidence [that] … the position of the surface of Titan [is] … near the liquidus in the CH4phase diagram [and, consequently, there is] …almost no methane ocean at all’ (Nature, 300, 731, 1982).We know very little about Titan and its surface; the way of checking into Sagan and Dermott's ideas appears to rest on the interpretation of radar reflectivity data. Preliminary attempts to obtain radar data were made in 1979 with the 305-m Arecibo telescope, but only broad limits resulted. The next opportunity for a measurement at Arecibo comes in the 1990's. Of course, the ideal circumstance would be to send spacecraft equipped with a radar reflectometer for a Titan flyby.

  17. Titan Orbiter Aerorover Mission

    NASA Technical Reports Server (NTRS)

    Sittler Jr., E. C.; Acuna, M.; Burchell, M. J.; Coates, A.; Farrell, W.; Flasar, M.; Goldstein, B. E.; Gorevan, S.; Hartle, R. E.; Johnson, W. T. K.

    2001-01-01

    We propose a combined Titan orbiter and Titan Aerorover mission with an emphasis on both in situ and remote sensing measurements of Titan's surface, atmosphere, ionosphere, and magnetospheric interaction. The biological aspect of the Titan environment will be emphasized by the mission (i.e., search for organic materials which may include simple organics to 'amono' analogues of amino acids and possibly more complex, lightening detection and infrared, ultraviolet, and charged particle interactions with Titan's surface and atmosphere). An international mission is assumed to control costs. NASA will provide the orbiter, launch vehicle, DSN coverage and operations, while international partners will provide the Aerorover and up to 30% of the cost for the scientific instruments through collaborative efforts. To further reduce costs we propose a single PI for orbiter science instruments and a single PI for Aerorover science instruments. This approach will provide single command/data and power interface between spacecraft and orbiter instruments that will have redundant central DPU and power converter for their instruments. A similar approach could be used for the Aerorover. The mission profile will be constructed to minimize conflicts between Aerorover science, orbiter radar science, orbiter radio science, orbiter imaging science, and orbiter fields and particles (FP) science. Additional information is contained in the original extended abstract.

  18. Preparation of PZT ferroelectric thick films by nanopowder-metal-organic decomposition process

    Microsoft Academic Search

    Kuo-shung Liu; Yai-yei Huang; Wen-jiun Lin; Tsang-lan Lin; I-nan Lin

    2000-01-01

    In this paper, a modified metal-organic decomposition (MOD) process has been developed for the fabrication of PZT thick films. Nano-sized PZT powders, around 5–15 nm, were first synthesized using hydrolysis of PZT alkoxide precursors, and then incorporated into a precursor containing PZT-carboxylates (0.2 M), followed by spin-coating process. The properties of nano-powder incorporated PZT precursors solution influences the spin-coating characteristics

  19. Determination of uranium in zircon

    USGS Publications Warehouse

    Cuttitta, F.; Daniels, G.J.

    1959-01-01

    A routine fluorimetric procedure is described for the determination of trace amounts of uranium in zircon. It employs the direct extraction of uranyl nitrate with ethyl acetate using phosphate as a retainer for zirconium. Submicrogram amounts or uranium are separated in the presence of 100,000 times the amount of zirconium. The modified procedure has been worked out using synthetic mixtures of known composition and zircon. Results of analyses have an accuracy of 97-98% of the contained uranium and a standard deviation of less than 2.5%. ?? 1959.

  20. The tides of Titan.

    PubMed

    Iess, Luciano; Jacobson, Robert A; Ducci, Marco; Stevenson, David J; Lunine, Jonathan I; Armstrong, John W; Asmar, Sami W; Racioppa, Paolo; Rappaport, Nicole J; Tortora, Paolo

    2012-07-27

    We have detected in Cassini spacecraft data the signature of the periodic tidal stresses within Titan, driven by the eccentricity (e = 0.028) of its 16-day orbit around Saturn. Precise measurements of the acceleration of Cassini during six close flybys between 2006 and 2011 have revealed that Titan responds to the variable tidal field exerted by Saturn with periodic changes of its quadrupole gravity, at about 4% of the static value. Two independent determinations of the corresponding degree-2 Love number yield k(2) = 0.589 ± 0.150 and k(2) = 0.637 ± 0.224 (2?). Such a large response to the tidal field requires that Titan's interior be deformable over time scales of the orbital period, in a way that is consistent with a global ocean at depth. PMID:22745254

  1. Impact craters on Titan

    USGS Publications Warehouse

    Wood, Charles A.; Lorenz, Ralph; Kirk, Randy; Lopes, Rosaly; Mitchell, Karl; Stofan, Ellen; Cassini RADAR Team

    2010-01-01

    Five certain impact craters and 44 additional nearly certain and probable ones have been identified on the 22% of Titan's surface imaged by Cassini's high-resolution radar through December 2007. The certain craters have morphologies similar to impact craters on rocky planets, as well as two with radar bright, jagged rims. The less certain craters often appear to be eroded versions of the certain ones. Titan's craters are modified by a variety of processes including fluvial erosion, mass wasting, burial by dunes and submergence in seas, but there is no compelling evidence of isostatic adjustments as on other icy moons, nor draping by thick atmospheric deposits. The paucity of craters implies that Titan's surface is quite young, but the modeled age depends on which published crater production rate is assumed. Using the model of Artemieva and Lunine (2005) suggests that craters with diameters smaller than about 35 km are younger than 200 million years old, and larger craters are older. Craters are not distributed uniformly; Xanadu has a crater density 2-9 times greater than the rest of Titan, and the density on equatorial dune areas is much lower than average. There is a small excess of craters on the leading hemisphere, and craters are deficient in the north polar region compared to the rest of the world. The youthful age of Titan overall, and the various erosional states of its likely impact craters, demonstrate that dynamic processes have destroyed most of the early history of the moon, and that multiple processes continue to strongly modify its surface. The existence of 24 possible impact craters with diameters less than 20 km appears consistent with the Ivanov, Basilevsky and Neukum (1997) model of the effectiveness of Titan's atmosphere in destroying most but not all small projectiles.

  2. Barium titanate nanocomposite capacitor FY09 year end report.

    SciTech Connect

    Stevens, Tyler E.; DiAntonio, Christopher Brian; Yang, Pin; Chavez, Tom P.; Winter, Michael R.; Monson, Todd C.; Roesler, Alexander William; Fellows, Benjamin D.

    2009-11-01

    This late start RTBF project started the development of barium titanate (BTO)/glass nanocomposite capacitors for future and emerging energy storage applications. The long term goal of this work is to decrease the size, weight, and cost of ceramic capacitors while increasing their reliability. Ceramic-based nanocomposites have the potential to yield materials with enhanced permittivity, breakdown strength (BDS), and reduced strain, which can increase the energy density of capacitors and increase their shot life. Composites of BTO in glass will limit grain growth during device fabrication (preserving nanoparticle grain size and enhanced properties), resulting in devices with improved density, permittivity, BDS, and shot life. BTO will eliminate the issues associated with Pb toxicity and volatility as well as the variation in energy storage vs. temperature of PZT based devices. During the last six months of FY09 this work focused on developing syntheses for BTO nanoparticles and firing profiles for sintering BTO/glass composite capacitors.

  3. Titan's Winter Polar Vortex

    NASA Technical Reports Server (NTRS)

    Flasar, F.M.; Achterberg, R.K.; Schinder, P.J.

    2008-01-01

    Titan's atmosphere has provided an interesting study in contrasts and similarities with Earth's. While both have N$_2$ as the dominant constituent and comparable surface pressures $\\sim1$ bar, Titan's next most abundant molecule is CH$_4$, not O$_2$, and the dissociative breakup of CH$_4$ and N$_2$ by sunlight and electron impact leads to a suite of hydrocarbons and nitriles, and ultimately the photochemical smog that enshrouds the moon. In addition, with a 15.95-day period, Titan is a slow rotator compared to Earth. While the mean zonal terrestrial winds are geostrophic, Titan's are mostly cyclostrophic, whipping around the moon in as little as 1 day. Despite the different dynamical regime, Titan's winter stratosphere exhibits several characteristics that should be familiar to terrestrial meteorologists. The cold winter pole near the 1 -mbar level is circumscribed by strong winds (up to 190 m/s) that act as a barrier to mixing with airmasses at lower latitudes. There is evidence of enhancement of several organic species over the winter pole, indicating subsidence. The adiabatic heating associated with this subsidence gives rise to a warm anomaly at the 0.01-mbar level, raising the stratopause two scale heights above its location at equatorial latitudes. Condensate ices have been detected in Titan's lower stratosphere within the winter polar vortex from infrared spectra. Although not always unambiguously identified, their spatial distribution exhibits a sharp gradient, decreasing precipitously across the vortex away from the winter pole. The interesting question of whether there is important heterogeneous chemistry occurring within the polar vortex, analogous to that occurring in the terrestrial polar stratospheric clouds in the ozone holes, has not been addressed. The breakup of Titan's winter polar vortex has not yet been observed. On Earth, the polar vortex is nonlinearly disrupted by interaction with large-amplitude planetary waves. Large-scale waves have not been identified in Titan's atmosphere, so the decay of its polar vortex may be more gradual than on Earth. Observations from an extended Cassini mission into late northern spring should provide critical data indicating whether the vortex goes away with a bang or just fades away.

  4. Microstructural development in solution derived PZT thin films

    SciTech Connect

    Headley, T.J.; Tuttle, B.A.; Voigt, J.A.; Michael, J.R.

    1994-03-01

    In the fabrication of PZT films by solution deposition techniques, control of phase evolution, microstructure, ferroelectric domain assemblage, etc. is important. Electron microscopy was used to correlate microstructure with film processing parameters.

  5. Fabrication of Flexible Piezoelectric PZT/Fabric Composite

    PubMed Central

    Chen, Caifeng; Hong, Daiwei; Wang, Andong; Ni, Chaoying

    2013-01-01

    Flexible piezoelectric PZT/fabric composite material is pliable and tough in nature which is in a lack of traditional PZT patches. It has great application prospect in improving the sensitivity of sensor/actuator made by piezoelectric materials especially when they are used for curved surfaces or complicated conditions. In this paper, glass fiber cloth was adopted as carrier to grow PZT piezoelectric crystal particles by hydrothermal method, and the optimum conditions were studied. The results showed that the soft glass fiber cloth was an ideal kind of carrier. A large number of cubic-shaped PZT nanocrystallines grew firmly in the carrier with a dense and uniform distribution. The best hydrothermal condition was found to be pH 13, reaction time 24?h, and reaction temperature 200°C. PMID:24348194

  6. Novel methods of powder preparation and ceramic forming for improving reliability of multilayer ceramic actuators

    Microsoft Academic Search

    William J. Dawson; Scott L. Swartz; Jean P. Issartel

    1993-01-01

    Critical components of many smart systems employ multilayer piezoelectric actuators based on lead zirconate titanate (PZT) ceramics. Applications include active vibration systems, noise suppression, acoustic camouflage, actuated structures, reconfigurable surfaces, and structural health monitoring. Two strategies involving novel materials processing techniques are discussed for improving the performance and reliability of PZT ceramic components. The first is the use of an

  7. COLD SPRAY ELECTRODING OF PIEZOELECTRIC CERAMIC

    Microsoft Academic Search

    P. C. King; S. H. Zahiri; M. Jahedi; J. Friend

    Lead zirconate titanate (PZT) is a piezoelectric material that is used in a wide range of applications from small actuators for the precise movement of lenses and mirrors to ultrasonic generators for the industrial mixing and emulsification of liquids. Conventional bonding of PZT involves the use of adhesives which dampen the movement of the element. This paper is a summary

  8. PLZT-based photovoltaic Piezoelectric Transformer with light feedback

    Microsoft Academic Search

    L. Kozielski; M. Adamczyk; J. Erhart

    2011-01-01

    Piezoelectric Transformer (PT) converts an electrical AC input voltage into ultrasonic vibrations and reconverts back to an output as AC voltage. Hard lead zirconate titanate (PZT) ceramics is typically used for fabrications of such devices. In case of lanthaniun ion La3+ addition in PZT solid solution we can achieve piezoelectric ceramics with good transparency exhibiting both optical Pockels and Kerr

  9. Radiation stability of gadolinium zirconate: A waste form for plutonium disposition

    Microsoft Academic Search

    S. X. Wang; B. D. Begg; L. M. Wang; R. C. Ewing; W. J. Weber; K. V. Govidan Kutty

    1999-01-01

    Zirconate and titanate pyrochlores were subjected to 1 MeV of Kr{sup +} irradiation. Pyrochlores in the Gdâ(ZrâTi{sub 1-x})âOâ system (x=0,0.25,0.5,0.75,1) showed a systematic change in the susceptibility to radiation-induced amorphization with increasing Zr content. GdâTiâOâ amorphized at relatively low dose (0.2 displacement per atom at room temperature), and the critical temperature for amorphization was 1100 K. With increasing zirconium content,

  10. Titan after Cassini Huygens

    Microsoft Academic Search

    P. M. Beauchamp; J. Lunine; J. Lebreton; A. Coustenis; D. Matson; K. Reh; C. Erd

    2008-01-01

    In 2005, the Huygens Probe gave us a snapshot of a world tantalizingly like our own, yet frozen in its evolution on the threshold of life. The descent under parachute, like that of Huygens in 2005, is happening again, but this time in the Saturn-cast twilight of winter in Titan's northern reaches. With a pop, the parachute is released, and

  11. The lakes of Titan

    Microsoft Academic Search

    E. R. Stofan; C. Elachi; J. I. Lunine; R. D. Lorenz; B. Stiles; K. L. Mitchell; S. Ostro; L. Soderblom; C. Wood; H. Zebker; S. Wall; M. Janssen; R. Kirk; R. Lopes; F. Paganelli; J. Radebaugh; L. Wye; Y. Anderson; M. Allison; R. Boehmer; P. Callahan; P. Encrenaz; E. Flamini; G. Francescetti; Y. Gim; S. Hensley; W. T. K. Johnson; K. Kelleher; D. Muhleman; P. Paillou; G. Picardi; F. Posa; L. Roth; R. Seu; S. Shaffer; S. Vetrella

    2007-01-01

    The surface of Saturn's haze-shrouded moon Titan has long been proposed to have oceans or lakes, on the basis of the stability of liquid methane at the surface. Initial visible and radar imaging failed to find any evidence of an ocean, although abundant evidence was found that flowing liquids have existed on the surface. Here we provide definitive evidence for

  12. Semiconducting barium titanate

    Microsoft Academic Search

    W. Heywang

    1971-01-01

    Barium titanate, which is well known as a basic ferroelectric material, is also of interest when doped because of the interaction between semiconductivity and ferroelectricity. The resistance of blocking layers at surfaces and grain-boundaries is governed mainly by the ferroelectric properties, so that a resistance jump of four decades is observed on heating above the Curie temperature. A survey of

  13. Methane rain on Titan

    Microsoft Academic Search

    O. B. Toon; C. P. Mckay; R. Courtin; T. P. Ackerman

    1988-01-01

    The atmosphere of Titan is characterized by means of model computations based on Voyager IRIS IR spectra and published data from laboratory determinations of absorption coefficients and cloud refractive indices. The results are presented in tables and graphs, and it is pointed out that the presence of Ar is not required in the model. Particular attention is given to the

  14. Clash of the Titans

    NSDL National Science Digital Library

    Karthigeyan Subramaniam

    2010-01-01

    WebQuests and the 5E learning cycle are titans of the science classroom. These popular inquiry-based strategies are most often used as separate entities, but the author has discovered that using a combined WebQuest and 5E learning cycle format taps into t

  15. Characteristics of zircon suitable for REE extraction

    NASA Astrophysics Data System (ADS)

    Watanabe, Y.; Hoshino, M.

    2011-12-01

    Zircons (ZrSiO4) from Naegi and Ohro granitic pegmatites, Japan and from Saigon alkaline basalt, Vietnam, were mineralogically characterized by inductively couples plasma mass spectrometry (ICP-MS), electron-microprobe analysis (EMPA), X-ray powder diffraction, micro-Raman spectroscopy and leaching experiment. The powder XRD and Raman spectra analyses show that the degree of crystallinity decreases from Saigon, to Ohro and Naegi zircons. Quantitative analytical results by the EMPA indicate that the Naegi and Ohro zircon samples contain a large amount of REE2O3, while REE contents in Saigon zircon are below detection limit. The leaching experiments for the present zircons under the condition of a solvent 1M-HCl, at a room temperature to 250 °C and retention time of 30h resulted in about 100 %, 50 % and 1 % recoveries of REE from the Naegi, Ohro and Saigon zircons, respectively. Leaching experiments for the Naegi zircon under the condition of a solvent 1N-HCl, heating temperature of 50 °C, 100 °C, 150 °C and 200 °C, and retention time 30h, showed that a significant amount of REE was leached out at a temperature above 150 °C. However, the leaching experiments of the Naegi and Ohro zircons at room temperature (about 25 °C) show that REE were hard to be leached. These results indicates that both low crystallinity of zircon and higher leaching temperature are requisite for effective leaching of REE from zircon.

  16. Titan atmospheric composition

    NASA Astrophysics Data System (ADS)

    Coustenis, A.; Cirs Investigation Team

    Titan s atmospheric composition has become known to us from the Voyager missions and more recently through the explorations by the ISO and Cassini instruments ISO has provided the detection of the water vapor in Titan s atmosphere Coustenis et al 1998 and given a precise measure of the chemical composition as a disk-average Coustenis et al 2003 More recently data recorded by the Composite Infrared Spectrometer CIRS aboard the Cassini spacecraft became available during the recent Titan flybys Flasar et al 2005 Teanby et al 2006 The spectra characterize various regions on Titan from 75 r S to 75 r N with a variety of emission angles We study the emission observed in the mid-infrared CIRS detector arrays covering roughly the 600-1500 cm -1 spectral range with apodized resolutions of 2 54 or 0 53 cm -1 The composite spectrum shows several molecular signatures hydrocarbons nitriles and CO 2 A firm detection of benzene C 6 H 6 is also provided by CIRS at 674 cm -1 We have used temperature profiles retrieved from the inversion of the emission observed in the methane nu 4 band at 1304 cm -1 and a line-by-line radiative transfer code to infer the abundances of the trace constituents and some of their isotopes in Titan s stratosphere Coustenis et al 2006 No longitudinal variations were found for the gases Information is retrieved on the meridional variations of the trace constituents and tied to predictions by dynamical-photochemical models Molecules showing a significant enhancement at

  17. Titanic Weather Forecasting

    NASA Astrophysics Data System (ADS)

    2004-04-01

    New Detailed VLT Images of Saturn's Largest Moon Optimizing space missions Titan, the largest moon of Saturn was discovered by Dutch astronomer Christian Huygens in 1655 and certainly deserves its name. With a diameter of no less than 5,150 km, it is larger than Mercury and twice as large as Pluto. It is unique in having a hazy atmosphere of nitrogen, methane and oily hydrocarbons. Although it was explored in some detail by the NASA Voyager missions, many aspects of the atmosphere and surface still remain unknown. Thus, the existence of seasonal or diurnal phenomena, the presence of clouds, the surface composition and topography are still under debate. There have even been speculations that some kind of primitive life (now possibly extinct) may be found on Titan. Titan is the main target of the NASA/ESA Cassini/Huygens mission, launched in 1997 and scheduled to arrive at Saturn on July 1, 2004. The ESA Huygens probe is designed to enter the atmosphere of Titan, and to descend by parachute to the surface. Ground-based observations are essential to optimize the return of this space mission, because they will complement the information gained from space and add confidence to the interpretation of the data. Hence, the advent of the adaptive optics system NAOS-CONICA (NACO) [1] in combination with ESO's Very Large Telescope (VLT) at the Paranal Observatory in Chile now offers a unique opportunity to study the resolved disc of Titan with high sensitivity and increased spatial resolution. Adaptive Optics (AO) systems work by means of a computer-controlled deformable mirror that counteracts the image distortion induced by atmospheric turbulence. It is based on real-time optical corrections computed from image data obtained by a special camera at very high speed, many hundreds of times each second (see e.g. ESO Press Release 25/01 , ESO PR Photos 04a-c/02, ESO PR Photos 19a-c/02, ESO PR Photos 21a-c/02, ESO Press Release 17/02, and ESO Press Release 26/03 for earlier NACO images, and ESO Press Release 11/03 for MACAO-VLTI results.) The southern smile ESO PR Photo 08a/04 ESO PR Photo 08a/04 Images of Titan on November 20, 25 and 26, 2002 Through Five Filters (VLT YEPUN + NACO) [Preview - JPEG: 522 x 400 pix - 40k] [Normal - JPEG: 1043 x 800 pix - 340k] [Hires - JPEG: 2875 x 2205 pix - 1.2M] Caption: ESO PR Photo 08a/04 shows Titan (apparent visual magnitude 8.05, apparent diameter 0.87 arcsec) as observed with the NAOS/CONICA instrument at VLT Yepun (Paranal Observatory, Chile) on November 20, 25 and 26, 2003, between 6.00 UT and 9.00 UT. The median seeing values were 1.1 arcsec and 1.5 arcsec respectively for the 20th and 25th. Deconvoluted ("sharpened") images of Titan are shown through 5 different narrow-band filters - they allow to probe in some detail structures at different altitudes and on the surface. Depending on the filter, the integration time varies from 10 to 100 seconds. While Titan shows its leading hemisphere (i.e. the one observed when Titan moves towards us) on Nov. 20, the trailing side (i.e the one we see when Titan moves away from us in its course around Saturn) - which displays less bright surface features - is observed on the last two dates. ESO PR Photo 08b/04 ESO PR Photo 08b/04 Titan Observed Through Nine Different Filters on November 26, 2002 [Preview - JPEG: 480 x 400 pix - 36k] [Normal - JPEG: 960 x 800 pix - 284k] Caption: ESO PR Photo 08b/04: Images of Titan taken on November 26, 2002 through nine different filters to probe different altitudes, ranging from the stratosphere to the surface. On this night, a stable "seeing" (image quality before adaptive optics correction) of 0.9 arcsec allowed the astronomers to attain the diffraction limit of the telescope (0.032 arcsec resolution). Due to these good observing conditions, Titan's trailing hemisphere was observed with contrasts of about 40%, allowing the detection of several bright features on this surface region, once thought to be quite dark and featureless. ESO PR Photo 08c/04 ESO PR Photo 08c/04 Titan Surface Projections [Previ

  18. Titan Student Centers Introduction and Overview ................................................. Section

    E-print Network

    de Lijser, Peter

    #12;Titan Student Centers Introduction and Overview ................................................. Section Page One One Titan Student Centers 2014-15 Fiscal Year Budget Charts and Tables .............................................................. Section Page Four Two Titan Student Centers 2014-15 Fiscal Year Budget Note Package

  19. Hydrocarbon Trapping in Titan Surface Materials

    NASA Astrophysics Data System (ADS)

    Cable, M. L.; Vu, T.; Choukroun, M.; Markus, C.; Hodyss, R.; Beauchamp, P.

    2014-02-01

    Benzene is found on Titan and is probably one of the most abundant evaporites to form around Titan lakes. We discovered trapping of ethane in crystalline benzene at 90 K, suggesting evaporite basins could act as hydrocarbon reservoirs on Titan.

  20. Fabrication and structural characterization of a resonant frequency PZT microcantilever

    NASA Astrophysics Data System (ADS)

    Zurn, S.; Hsieh, M.; Smith, G.; Markus, D.; Zang, M.; Hughes, G.; Nam, Y.; Arik, M.; Polla, D.

    2001-04-01

    The fabrication and structural characterization of a surface micromachined, resonant frequency, Pb(Zr, Ti)O3 (PZT) microcantilever will be presented. The PZT microcantilever was fabricated using surface micromachining techniques, and used a low-stress silicon nitride thin film as the base material for the microcantilever onto which a PZT thin film was incorporated. The PZT thin film is used as both the microsensor and the microactuator. A unique fabrication procedure was developed in order to eliminate the step of encapsulating the PZT during the removal of the spacer layer. The encapsulation step was avoided because of the difficulty in finding a suitable material, which would protect the PZT during the removal of the spacer layer yet not affect its material properties. This predicament was resolved by removing the spacer layer prior to the deposition of the PZT. The microcantilevers were characterized extensively using an atomic force microscope in an unusual manner. The atomic force microscope was modified in such a fashion that the deflection at the tip of the microcantilever could be measured as the frequency of an electrical signal applied to the PZT thin film was varied. In addition, an impedance analyzer was used to characterize the microcantilevers. Simple thin-film, laminated plate theory was used to obtain a closed-form solution for the modal response of the microcantilever, while ANSYS was used to obtain modal and harmonic simulation results. It will be shown that the experimental, numerical, and theoretical modal results are within +/-10% of one another. The experimental and numerical harmonic results differ by an order of magnitude; however, the numerical model is currently being modified to more accurately represent the PZT microcantilever. From the information gathered during the structural characterization of the PZT microcantilever, it will be shown that certain higher-order resonant frequency modes have very large mechanical responses. These higher-order resonant frequency modes give designers another parameter to adjust when trying to optimize the design of their resonant frequency device.

  1. Alpine zircon fission-track ages in the Rhne and Rhine rivers DOWNSTREAM CHANGES OF ALPINE ZIRCON

    E-print Network

    Paris-Sud XI, Université de

    Alpine zircon fission-track ages in the Rhône and Rhine rivers DOWNSTREAM CHANGES OF ALPINE ZIRCON, Bellingham, Washington, 98225, U.S.A. Keywords: detrital, zircon, fission-track, Rhône River, Rhine River Manuscript received: #12;Alpine zircon fission-track ages in the Rhône and Rhine rivers 2 ABSTRACT Zircons

  2. Titan Mare Explorer (TiME): A Discovery Mission to Titan’s Hydrocarbon Lakes

    NASA Astrophysics Data System (ADS)

    Lorenz, R. D.; Stofan, E. R.; Lunine, J. I.; Kirk, R. L.; Mahaffy, P. R.; Bierhaus, B.; Aharonson, O.; Clark, B. C.; Kantsiper, B.; Ravine, M. A.; Waite, J. H.; Harri, A.; Griffith, C. A.; Trainer, M. G.

    2009-12-01

    The discovery of lakes in Titan’s high latitudes confirmed the expectation that liquid hydrocarbons exist on the surface of the haze-shrouded moon. The lakes fill through drainage of subsurface runoff and/or intersection with the subsurface alkanofer, providing the first evidence for an active condensable-liquid hydrological cycle on another planetary body. The unique nature of Titan’s methane cycle, along with the prebiotic chemistry and implications for habitability of Titan’s lakes, make the lakes of the highest scientific priority for in situ investigation. The Titan Mare Explorer mission is an ASRG (Advanced Stirling Radioisotope Generator)-powered mission to a lake on Titan. The mission would be the first exploration of a planetary sea beyond Earth, would demonstrate the ASRG both in deep space and a non-terrestrial atmosphere environment, and pioneer low-cost outer planet missions. The scientific objectives of the mission are to: determine the chemistry of a Titan lake to constrain Titan’s methane cycle; determine the depth of a Titan lake; characterize physical properties of liquids; determine how the local meteorology over the lakes ties to the global cycling of methane; and analyze the morphology of lake surfaces, and if possible, shorelines, in order to constrain the kinetics of liquids and better understand the origin and evolution of Titan lakes. The focused scientific goals, combined with the new ASRG technology and the unique mission design, allows for a new class of mission at much lower cost than previous outer planet exploration has required.

  3. Inelastic neutron scattering from zircon

    SciTech Connect

    Nipko, J.C.; Loong, C.K.

    1997-07-14

    A lattice dynamical investigation of zircon (ZrSiO{sub 4}) has been carried out to obtain a microscopic understanding of its thermodynamic properties, as well as to examine possible soft modes that may contribute to the phase transformation to scheelite type under high pressure. We have measured the neutron weighted phonon density of states of zircon from a polycrystalline sample. The neutron spectra reveal one-phonon excitations extending to 1130 cm{sup -1}, with phonon bands centered at 226, 298, 363, 540, 661, 726, 945, and 1081 cm{sup -1}. A quantitative analysis of the neutron results was carried out using a lattice dynamical rigid-ion model. 4 refs., 3 figs.

  4. Reaction, transformation and delamination of samarium zirconate thermal barrier coatings

    E-print Network

    Wadley, Haydn

    Reaction, transformation and delamination of samarium zirconate thermal barrier coatings Hengbei online 24 March 2011 Keywords: Samarium zirconate Interface reaction Bilayers Delamination The rare earth zirconates have attracted interest for thermal barrier coatings (TBCs) because they have very low intrinsic

  5. Properties of Semiconductive Barium Titanates

    Microsoft Academic Search

    Osamu Saburi

    1959-01-01

    The resistivity of barium titanate which is usually of the order of 109˜1012 ohm-cm, may be remarkably reduced with suitable control in valency. The valency-controlled barium titanate, whose resistivity is of the order of 10˜104 ohm-cm at room temperature, shows anomalous positive character in the temperature dependency of the resistivity. For example, the resistivity of barium titanate containing 0.1 mol.

  6. Observing Titan with amateur equipment

    NASA Astrophysics Data System (ADS)

    Lorenz, Ralph D.; Hergenrother, Carl; White, Brooke; West, J. Doug; Fujii, Mitsugu; Hatton, Jason

    We survey the observations of Titan that can be made using equipment available to amateur astronomers. Off-the-shelf hardware includes spectrometers and photometers that can detect Titan's infrared light curve and potentially its clouds. CCD spectra and photometry (both photoelectric and CCD), even with small (20 cm) telescopes, are useful for monitoring seasonal changes in Titan's haze. Recent remarkable advances in automatic stacking of thousands of short-exposure images obtained with webcams may even permit Titan's disk to be resolved. We additionally report some observations made with amateur equipment mounted on the 1.64 m Gerard P. Kuiper telescope on Mt. Bigelow.

  7. Organic chemistry on Titan

    NASA Technical Reports Server (NTRS)

    Chang, S.; Scattergood, T.; Aronowitz, S.; Flores, J.

    1979-01-01

    Features taken from various models of Titan's atmosphere are combined in a working composite model that provides environmental constraints within which different pathways for organic chemical synthesis are determined. Experimental results and theoretical modeling suggest that the organic chemistry of the satellite is dominated by two processes: photochemistry and energetic particle bombardment. Photochemical reactions of CH4 in the upper atmosphere can account for the presence of C2 hydrocarbons. Reactions initiated at various levels of the atmosphere by cosmic rays, Saturn 'wind', and solar wind particle bombardment of a CH4-N2 atmospheric mixture can account for the UV-visible absorbing stratospheric haze, the reddish appearance of the satellite, and some of the C2 hydrocarbons. In the lower atmosphere photochemical processes will be important if surface temperatures are sufficiently high for gaseous NH3 to exist. It is concluded that the surface of Titan may contain ancient or recent organic matter (or both) produced in the atmosphere.

  8. Titanic exploration with GIS

    USGS Publications Warehouse

    Kerski, J.J.

    2004-01-01

    To help teachers and students investigate one of the world's most famous historical events using the geographic perspective and GIS tools and methods, the U.S. Geological Survey (USGS) created a set of educational lessons based on the RMS Titanic's April 1912 sailing. With these lessons, student researchers can learn about latitude and longitude, map projections, ocean currents, databases, maps, and images through the analysis of the route, warnings, sinking, rescue, and eventual discovery of the submerged ocean liner in 1985. They can also consider the human and physical aspects of the maiden voyage in the North Atlantic Ocean at a variety of scales, from global to regional to local. Likewise, their investigations can reveal how the sinking of the Titanic affected future shipping routes.

  9. Flexible PZT thin film tactile sensor for biomedical monitoring.

    PubMed

    Tseng, Hong-Jie; Tian, Wei-Cheng; Wu, Wen-Jong

    2013-01-01

    This paper presents the development of tactile sensors using the sol-gel process to deposit a PZT thin-film from 250 nm to 1 ?m on a flexible stainless steel substrate. The PZT thin-film tactile sensor can be used to measure human pulses from several areas, including carotid, brachial, finger, ankle, radial artery, and the apical region. Flexible PZT tactile sensors can overcome the diverse topology of various human regions and sense the corresponding signals from human bodies. The measured arterial pulse waveform can be used to diagnose hypertension and cardiac failure in patients. The proposed sensors have several advantages, such as flexibility, reliability, high strain, low cost, simple fabrication, and low temperature processing. The PZT thin-film deposition process includes a pyrolysis process at 150 °C/500 °C for 10/5 min, followed by an annealing process at 650 °C for 10 min. Finally, the consistent pulse wave velocity (PWV) was demonstrated based on human pulse measurements from apical to radial, brachial to radial, and radial to ankle. It is characterized that the sensitivity of our PZT-based tactile sensor was approximately 0.798 mV/g. PMID:23698262

  10. Flexible PZT Thin Film Tactile Sensor for Biomedical Monitoring

    PubMed Central

    Tseng, Hong-Jie; Tian, Wei-Cheng; Wu, Wen-Jong

    2013-01-01

    This paper presents the development of tactile sensors using the sol-gel process to deposit a PZT thin-film from 250 nm to 1 ?m on a flexible stainless steel substrate. The PZT thin-film tactile sensor can be used to measure human pulses from several areas, including carotid, brachial, finger, ankle, radial artery, and the apical region. Flexible PZT tactile sensors can overcome the diverse topology of various human regions and sense the corresponding signals from human bodies. The measured arterial pulse waveform can be used to diagnose hypertension and cardiac failure in patients. The proposed sensors have several advantages, such as flexibility, reliability, high strain, low cost, simple fabrication, and low temperature processing. The PZT thin-film deposition process includes a pyrolysis process at 150 °C/500 °C for 10/5 min, followed by an annealing process at 650 °C for 10 min. Finally, the consistent pulse wave velocity (PWV) was demonstrated based on human pulse measurements from apical to radial, brachial to radial, and radial to ankle. It is characterized that the sensitivity of our PZT-based tactile sensor was approximately 0.798 mV/g. PMID:23698262

  11. Crystalline titanate catalyst supports

    SciTech Connect

    Anthony, R.G.; Dosch, R.G.

    1991-12-31

    A series of new crystalline titanates (CT) are shown to have considerable potential as catalyst supports. For Pd supported catalyst, the catalytic activity for pyrene hydrogenation was substantially different depending on the type of CT, and one was substantially more active than Pd on hydrous titanium oxide (HTO). For 1-hexene hydrogenation the activities of the new CTs were approximately the same as for the hydrous metal oxide supports.

  12. Crystalline titanate catalyst supports

    DOEpatents

    Anthony, Rayford G. (Bryan, TX); Dosch, Robert G. (Albuquerque, NM)

    1993-01-01

    A series of new crystalline titanates (CT) are shown to have considerable potential as catalyst supports. For Pd supported catalyst, the catalytic activity for pyrene hydrogenation was substantially different depending on the type of CT, and one was substantially more active than Pd on hydrous titanium oxide (HTO). For 1-hexene hydrogenation the activities of the new CTs were approximately the same as for the hydrous metal oxide supports.

  13. Crystalline titanate catalyst supports

    DOEpatents

    Anthony, R.G.; Dosch, R.G.

    1993-01-05

    A series of new crystalline titanates (CT) are shown to have considerable potential as catalyst supports. For Pd supported catalyst, the catalytic activity for pyrene hydrogenation was substantially different depending on the type of CT, and one was substantially more active than Pd on hydrous titanium oxide (HTO). For 1-hexene hydrogenation the activities of the new CTs were approximately the same as for the hydrous metal oxide supports.

  14. Hydrocarbon lakes on Titan

    Microsoft Academic Search

    Giuseppe Mitri; Adam P. Showman; Jonathan I. Lunine; Ralph D. Lorenz

    2007-01-01

    The Huygens Probe detected dendritic drainage-like features, methane clouds and a high surface relative humidity (?50%) on Titan in the vicinity of its landing site [Tomasko, M.G., and 39 colleagues, 2005. Nature 438, 765–778; Niemann, H.B., and 17 colleagues, 2005. Nature 438, 779–784], suggesting sources of methane that replenish this gas against photo- and charged-particle chemical loss on short (10–100)

  15. A 1-V Operated MEMS Variable Optical Attenuator Using Piezoelectric PZT Thin-Film Actuators

    Microsoft Academic Search

    Chengkuo Lee; Fu-Li Hsiao; Takeshi Kobayashi; Kah How Koh; P. V. Ramana; Wenfeng Xiang; Bin Yang; Chee Wei Tan; D. Pinjala

    2009-01-01

    A rotational Si mirror driven by PZT actuators has been investigated for variable optical attenuator (VOA) applications. The PZT actuators deploy 3.1-mum PZT layer. The developed PZT-driven microelectromechanical systems VOA comprising a large Si reflection mirror integrated with a dual core fiber collimator in 3-D light attenuation arrangement. The curve of the attenuation versus driving voltage shows rather uniform changing

  16. Wafer-Level Transfer Technologies for PZT-Based RF MEMS Switches

    Microsoft Academic Search

    Roland Guerre; Ute Drechsler; Debabrata Bhattacharyya; Pekka Rantakari; Richard Stutz; Robert V. Wright; Zlatoljub D. Milosavljevic; Tauno Vaha-Heikkila; Paul B. Kirby; Michel Despont

    2010-01-01

    We report on wafer-level transfer technologies to integrate PZT-based radio frequency (RF) microelectromechanical-systems switches on CMOS. Such heterogeneous integration can overcome the incompatibility of PZT material with back-end-of-the-line (BEOL) CMOS technology. The PZT stack and the transfer process have been optimized to avoid degradation of the PZT actuators during the transfer. In particular, we have optimized the seed layer for

  17. Design and Experiment of PZT Network-based Structural Health Monitoring Scanning System

    Microsoft Academic Search

    Qiu Lei; Yuan Shenfang; Wang Qiang; Sun Yajie; Yang Weiwei

    2009-01-01

    The active Lamb wave and piezoelectric transducer (PZT)-based structural health monitoring (SHM) technology is a kind of efficient approach to estimate the health state of aircraft structure. In practical applications, PZT networks are needed to monitor large scale structures. Scanning many of the different PZT actuator-sensor channels within these PZT networks to achieve on-line SHM task is important. Based on

  18. Characterization of nanostructured ceramics prepared by both high energy ball milling and fast firing sintering processes

    Microsoft Academic Search

    Y. Leyet; F. Guerrero; E. Pérez-Delfín; J. Pérez de la Cruz; J. A. Eiras

    2012-01-01

    High-energy ball milling technique was successfully applied to calcinated lead zirconate titanate (PZT 60\\/40) powders. After 20?h of ball milling, large PZT particles were completely broken down, reducing its initial size in three orders of magnitude. Experimental results show a huge sinterability enhancement of the PZT powders by using this technique, achieving its maximum sintering rate at ?800°C. Relatively low

  19. Characterization of nanostructured ceramics prepared by both high energy ball milling and fast firing sintering processes

    Microsoft Academic Search

    Y. Leyet; F. Guerrero; E. Pérez-Delfín; J. Pérez de la Cruz; J. A. Eiras

    2011-01-01

    High-energy ball milling technique was successfully applied to calcinated lead zirconate titanate (PZT 60\\/40) powders. After 20?h of ball milling, large PZT particles were completely broken down, reducing its initial size in three orders of magnitude. Experimental results show a huge sinterability enhancement of the PZT powders by using this technique, achieving its maximum sintering rate at ?800°C. Relatively low

  20. Piezoelectric thin films formed by MOD on cantilever beams for micro sensors and actuators

    Microsoft Academic Search

    T. Cui; D. Markus; S. Zurn; D. L. Polla

    2004-01-01

    Novel piezoelectric cantilever beams for micro sensors and actuators based on PZT thin films have been batch fabricated by surface micromachining. Lead zirconate titanate (PZT) thin film is formed by metalorganic deposition (MOD) on Pt\\/Ti\\/SiO 2\\/Si (1 0 0) substrates and Pt\\/Ti\\/LTO\\/Si 3N 4 cantilever beams and then annealed at 700 °C in air. The PZT thin film is 0.5

  1. Titan's neutral atmospheric composition

    NASA Astrophysics Data System (ADS)

    Coustenis, A.; Jennings, D.; Jolly, A.; Bénilan, Y.; Vinatier, S.; Nixon, C.; Gautier, D.; Bjoraker, G.; Romani, P.; Flasar, M.

    2007-08-01

    Our understanding of Titan's atmospheric chemical composition has recently been enhanced by the data returned by the Cassini instruments. Spectra recorded by the Composite Infrared Spectrometer (CIRS) aboard the Cassini spacecraft have been processed from the Titan flybys spanning three years now since SOI (Flasar et al., 2005; Teanby et al., 2006, Vinatier et al., 2006; Nixon et al., 2006; Coustenis et al., 2007). The spectra characterize various regions on Titan from 85°S to 80°N with a variety of emission angles. We have studied the emission observed in the CIRS detector arrays (covering the 10-1500 cm-1 spectral range with apodized resolutions of 2.54 or 0.53 cm-1). We have used temperature profiles retrieved from the inversion of the emission observed in the methane v4 band at 1304 cm-1 and a line-by-line radiative transfer code to infer the abundances of the trace constituents and some of their isotopes in Titan's stratosphere (Coustenis et al., 2007a). The composite spectra show several signatures of previously identified molecules: hydrocarbons, nitriles, H2O and CO2. Besides these well-known trace species, a firm detection of benzene (C6H6) is provided by CIRS at 674 cm-1 and allows for the study of its latitudinal variations. No longitudinal variations were found for any of the gases. Information is retrieved on the meridional variations of the trace constituents and tied to predictions by dynamicalphotochemical models (Hourdin et al., 2004; Lavvas et al., 2007). Molecules showing a significant enhancement at northern latitudes are the nitriles (HC3N, HCN) and the complex hydrocarbons (C4H2, C3H4). The D/H ratio on Titan was also determined from the CH3D band at 8.6 micron and found to be about 1.3 ±0.2 10-4. We have also identified the presence of C2HD at 678 cm-1 for the first time (Coustenis et al., 2007b, in preparation). Constraints are also set on the vertical distribution of C2H2. References : Coustenis et al., 2007a, Icarus, in press; Flasar et al., 2005, Science 308, 975 ; Hourdin et al., 2004, J. Geophys. Res. 109, E1205; Nixon et al., 2006, BAAS 38; Lavvas et al., 2007, Plan. Space Sci., in press; Teanby et al., 2006, Icarus 181, 243; Vinatier et al., 2006, Icarus, 188, 120.

  2. Geomorphic Units on Titan

    NASA Astrophysics Data System (ADS)

    Lopes, Rosaly; Malaska, Michael; Schoenfeld, Ashley; Birch, Samuel; Hayes, Alexander; Solomonidou, Anezina; Radebaugh, Jani

    2015-04-01

    The Cassini-Huygens mission has revealed the surface of Titan in unprecedented detail. The Synthetic Aperture Radar (SAR) mode on the Cassini Titan Radar Mapper is able to penetrate clouds and haze to provide high resolution (~350 m spatial resolution at best) views of the surface geology. The instrument's other modes (altimetry, scatterometry, radiometry) also provide valuable data for interpreting the geology, as do other instruments on Cassini, in particular, the Imaging Science Subsystem (ISS) and the Visual and Infrared Mapping Spectrometer (VIMS). Continuing the initial work described in Lopes et al. (2010, Icarus, 212, 744-750), we have established the major geomorphologic unit classes on Titan using data from flybys Ta through T92 (October 2004-July 2013). We will present the global distribution of the major classes of units and, where there are direct morphological contacts, describe how these classes of units relate to each other in terms of setting and emplacement history. The classes of units are mountainous/hummocky terrains, plains, dunes, labyrinthic terrains and lakes. The oldest classes of units are the mountainous/hummocky and the labyrinthic terrains. The mountainous/hummocky terrains consist of mountain chains and isolated radar-bright terrains. The labyrinthic terrains consist of highly incised dissected plateaux with medium radar backscatter. The plains are younger than both mountainous/hummocky and labyrinthic unit classes. Dunes and lakes are the youngest unit classes on Titan; no contact is observed between the dunes and lakes but it is likely that both processes are still active. We have identified individual features such as craters, channels, and candidate cryovolcanic features. Characterization and comparison of the properties of the unit classes and the individual features with data from radiometry, ISS, and VIMS provides information on their composition and possible provenance. We can use these correlations to also infer global distribution on regions not covered by SAR. This is particularly important as SAR data will not provide complete coverage of Titan by the end of the Cassini mission.

  3. Temperature dependent XAFS studies of local atomic structure of the perovskite-type zirconates

    SciTech Connect

    Vedrinskii, R. V.; Lemeshko, M. P.; Novakovich, A. A. [Institute of Physics, Rostov State University, 194 Stachky Avenue, Rostov-on-Don 344090 (Russian Federation); Nazarenko, E. S. [Institute of Physics, Rostov State University, 194 Stachky Avenue, Rostov-on-Don 344090 (Russian Federation); Laboratoire de Cristallographie, CNRS, l'Universite Joseph Fourier, 166 Boite Postale, F-38042 Grenoble Cedex 9 (France); Nassif, V. [CEA/Grenoble, DRFMC/SP2M/NRS, F-38054 Grenoble Cedex 9 (France); BM30b CRG-FAME, European Synchrotron Radiation Facility, F-38043 Grenoble Cedex 9 (France); Proux, O. [Laboratoire de Geophysique Interne et Tectonophysique, UMR CNRS, Universite Joseph Fourier, F-38400 Saint-Martin-D'Heres (France); BM30b CRG-FAME, European Synchrotron Radiation Facility, F-38043 Grenoble Cedex 9 (France); Joly, Y. [Laboratoire de Cristallographie, CNRS, l'Universite Joseph Fourier, 166 Boite Postale, F-38042 Grenoble Cedex 9 (France)

    2006-04-01

    Temperature dependent preedge and extended x-ray absorption fine structure measurements at the Zr K edge for the perovskite-type zirconates PbZr{sub 0.515}Ti{sub 0.485}O{sub 3} (PZT), PbZrO{sub 3} (PZ), and BaZrO{sub 3} are performed. To carry out a more accurate study of the weak reconstruction of the local atomic structure we employed a combination of two techniques: (i) analysis of the preedge fine structure, and (ii) analysis of the Fourier transform of the difference between {chi}(k) functions obtained at different temperatures. A detailed investigation of local atomic structure in the cubic phase for all the crystals is also performed. It is shown that neither the displacive nor the order-disorder model can describe correctly the changes of local atomic structure during phase transitions in PZ and PZT. A spherical model describing the local atomic structure of perovskite-type crystals suffering structural phase transitions is proposed.

  4. Titan's Methane Cycle is Closed

    NASA Astrophysics Data System (ADS)

    Hofgartner, J. D.; Lunine, J. I.

    2013-12-01

    Doppler tracking of the Cassini spacecraft determined a polar moment of inertia for Titan of 0.34 (Iess et al., 2010, Science, 327, 1367). Assuming hydrostatic equilibrium, one interpretation is that Titan's silicate core is partially hydrated (Castillo-Rogez and Lunine, 2010, Geophys. Res. Lett., 37, L20205). These authors point out that for the core to have avoided complete thermal dehydration to the present day, at least 30% of the potassium content of Titan must have leached into an overlying water ocean by the end of the core overturn. We calculate that for probable ammonia compositions of Titan's ocean (compositions with greater than 1% ammonia by weight), that this amount of potassium leaching is achievable via the substitution of ammonium for potassium during the hydration epoch. Formation of a hydrous core early in Titan's history by serpentinization results in the loss of one hydrogen molecule for every hydrating water molecule. We calculate that complete serpentinization of Titan's core corresponds to the release of more than enough hydrogen to reconstitute all of the methane atoms photolyzed throughout Titan's history. Insertion of molecular hydrogen by double occupancy into crustal clathrates provides a storage medium and an opportunity for ethane to be converted back to methane slowly over time--potentially completing a cycle that extends the lifetime of methane in Titan's surface atmosphere system by factors of several to an order of magnitude over the photochemically-calculated lifetime.

  5. PZT\\/ZnO actuator responding to reducing gases

    Microsoft Academic Search

    Yuji Isogai; Masaru Miyayama; Hiroaki Yanagida

    1996-01-01

    The bending behaviour of a piezoelectric actuator consisting of a dense PZT (Pb0.995Nb0.01(Zr0.53Ti0.47)0.99O3) plate and a porous ZnO (ZnO + 10 mol% NiO + 0.2 mol% Li2O) plate in response to reducing-gas (CO, H2) atmospheres has been investigated. The actuator is prepared by bonding the dense PZT and press-formed ZnO disks using a hot-press technique with glass frits at the

  6. Titan Tusk Force Student Engagement Report

    E-print Network

    de Lijser, Peter

    Titan Tusk Force Student Engagement Report FY 2008-2009 Mission Statement The mission of Titan Tusk Force is to develop a strong sense of campus unity, pride and identity with CSUF. Titan Tusk Force, Incorporated here at California State University, Fullerton. Program Overview Titan Tusk Force (TTF) functions

  7. Titan Parents Association Scholarship Spring 2012

    E-print Network

    de Lijser, Peter

    Titan Parents Association Scholarship Spring 2012 Amount: $500 Established by: Titan Parents Association This program was established by the Cal State Fullerton Titan Parents Association. Scholarship campaigns and Titan Parents programs and events. Funds must be used for the upcoming academic semester

  8. Titan Tusk Force Student Engagement Report

    E-print Network

    de Lijser, Peter

    Titan Tusk Force Student Engagement Report FY 2009-2010 Mission Statement The mission of Titan Tusk Force is to develop a strong sense of campus unity, pride and identity with CSUF. Titan Tusk Force, Incorporated here at California State University, Fullerton. Program Overview Titan Tusk Force (TTF) functions

  9. Titan Tusk Force Student Engagement Report

    E-print Network

    de Lijser, Peter

    Titan Tusk Force Student Engagement Report FY 2011-2012 Mission Statement The mission of Titan Tusk Force is to develop a strong sense of campus unity, pride and identity with CSUF. Titan Tusk Force, Incorporated here at California State University, Fullerton. Program Overview Titan Tusk Force (TTF) functions

  10. Titan Tusk Force Student Engagement Report

    E-print Network

    de Lijser, Peter

    Titan Tusk Force Student Engagement Report FY 2010-2011 Mission Statement The mission of Titan Tusk Force is to develop a strong sense of campus unity, pride and identity with CSUF. Titan Tusk Force, Incorporated here at California State University, Fullerton. Program Overview Titan Tusk Force (TTF) functions

  11. The commercial Titan launch vehicle

    NASA Astrophysics Data System (ADS)

    Troutman, J.; Isakowitz, S.

    1987-06-01

    Martin Marietta is making available a commercial version of the Titan launch vehicle. At a total payload weight capability of 31,600 pounds to low earth orbit, the commercial Titan provides Shuttle and Ariane compatible services to the commercial satellite community. This paper describes the commercial Titan which is based on the U.S. Air Force Titan 34D. A large diameter payload fairing and extension module provide for single or dual payload installation. Structural and some equipment rearrangement modifications have been made to the Stage II forward skirt to handle the larger payload fairing and loads involved in commercial operation. Stage II has been stretched and the liquid rocket engines enhanced to improve lift performance. The solid rocket motors and avionics remain unchanged. Plans to utilize Transtage on top a Titan III for direct injection into geosynchronous transfer orbit are being studied for future launches.

  12. Synthesis and electrical analysis of nano-crystalline barium titanate nanocomposites for use in high-energy density applications.

    SciTech Connect

    DiAntonio, Christopher Brian; Yang, Pin; Chavez, Tom P.; Huber, Dale L.; Winter, Michael R.; Monson, Todd C.; Roesler, Alexander William

    2010-10-01

    Ceramic based nanocomposites have recently demonstrated the ability to provide enhanced permittivity, increased dielectric breakdown strength, and reduced electromechanical strain making them potential materials systems for high energy density applications. A systematic characterization and optimization of barium titanate and PLZT based nanoparticle composites employing a glass or polymer matrix to yield a high energy density component will be presented. This work will present the systematic characterization and optimization of barium titanate and lead lanthanum zirconate titanate nanoparticle based ceramics. The nanoparticles have been synthesized using solution and pH-based synthesis processing routes and employed to fabricate polycrystalline ceramic and nanocomposite based components. The dielectric/ferroelectric properties of these various components have been gauged by impedance analysis and electromechanical response and will be discussed.

  13. Zircon-rutile-ilmenite froth flotation process

    SciTech Connect

    Schmidt, R.; Denham, D.L. Jr.

    1992-04-21

    This patent describes a method for separating a mixture of minerals comprising at least zircon, ilmenite and rutile. It comprises adding an acid solution to the mixture to acidify to a pH of between about 2.0 and 6.0; adding starch to the mixture to depress the ilmenite and the rutile; adding a source of fluoride ions to the mixture to provide a negative surface charge on the zircon surface to activate the zircon; adding an amine cationic collector to the mixture to float the activated zircon; subjecting the mixture containing the added acid solution, the fluoride ions, the starch and the cationic collector, to froth flotation; and withdrawing a float product comprising the zircon and a sink product comprising the ilmenite and rutile.

  14. Zircon refractories for glass-melting (review)

    SciTech Connect

    Mel'nikova, I.G.; Nesterova, T.A.; Razdol'skaya, I.V.

    1986-03-01

    The compositions, some of the properties, and the field of application of zircon refractories produced for glass melting in the USSR and abroad are presented. The studies show that the zircon refractories of enhanced purity with a total concentration of coloring impurities of 0.3% are of particular interest in the melting of several grades of special glasses. Data on the glass resitance of zircon refractories to a series of special glasses are presented; the data were obtained using a dynamic method in a comparison with fused quartz. The degree of corrosion was evaluated from the change in the monitored volume of the specimens before and after contact with the glass. It is clear that the corrosion of the zircon refractories both pressed and also obtained by slip casting is significantly less than the corrosion of refractories made from fused quartz. The zircon refractories can reasonably be used for melting a series of glasses with a low concentration of alkalis.

  15. Enhanced dielectric properties from barium strontium titanate films with strontium titanate buffer layers

    E-print Network

    Alpay, S. Pamir

    Enhanced dielectric properties from barium strontium titanate films with strontium titanate buffer in their PE state. One of the leading material candidates for tunable materials is barium strontium titanate

  16. Zinc titanate sorbents

    DOEpatents

    Gupta, R.P.; Gangwal, S.K.; Jain, S.C.

    1998-02-03

    The present invention provides a zinc titanate sorbent material useful in desulfurization applications. The zinc titanate material is in the form of generally spherical particles of substantially uniform chemical distribution. The sorbent material is capable of absorbing sulfur compounds from a gaseous feed in an amount of at least about 15 weight percent based on the weight of the sorbent. The sorbent material is prepared by a process including: (a) forming a zinc oxide/titanium dioxide dry blend, (b) preparing a substantially uniform aqueous slurry comprising the zinc oxide/titanium dioxide dry blend, organic binder, and at least about 1 weight percent inorganic binder based on the solids weight of the slurry, (c) spray drying the slurry to produce substantially spherical particles, and (d) calcining the particles at a temperature of between about 750 to about 950 C. The dry blend is formed by mixing between about 0.5 to about 2 parts zinc oxide having a median particle size of less than about 0.5 microns, and about 1 part titanium dioxide having a median particle size of less than about 1 micron. The slurry contains substantially no free silica and may be prepared by the process including (1) preparing an aqueous solution of organic binder, (2) adding the dry blend to the aqueous solution of organic binder, and (3) adding the inorganic binder to the solution of organic binder, and blend. Additional reagents, such as a surfactant, may also be incorporated into the sorbent material. The present invention also provides a process for desulfurizing a gaseous stream. The process includes passing a gaseous stream through a reactor containing an attrition resistant zinc titanate sorbent material of the present invention.

  17. Zinc titanate sorbents

    DOEpatents

    Gupta, Raghubir P. (Durham, NC); Gangwal, Santosh K. (Durham, NC); Jain, Suresh C. (Germantown, MD)

    1998-01-01

    The present invention provides a zinc titanate sorbent material useful in desulfurization applications. The zinc titanate material is in the form of generally spherical particles of substantially uniform chemical distribution. The sorbent material is capable of absorbing sulfur compounds from a gaseous feed in an amount of at least about 15 weight percent based on the weight of the sorbent. The sorbent material is prepared by a process including: (a) forming a zinc oxide/titanium dioxide dry blend, (b) preparing a substantially uniform aqueous slurry comprising the zinc oxide/titanium dioxide dry blend, organic binder, and at least about 1 weight percent inorganic binder based on the solids weight of the slurry, (c) spray drying the slurry to produce substantially spherical particles, and (d) calcining the particles at a temperature of between about 750.degree. C. to about 950.degree. C. The dry blend is formed by mixing between about 0.5 to about 2 parts zinc oxide having a median particle size of less than about 0.5 .mu., and about 1 part titanium dioxide having a median particle size of less than about 1 .mu.. The slurry contains substantially no free silica and may be prepared by the process including (1) preparing an aqueous solution of organic binder, (2) adding the dry blend to the aqueous solution of organic binder, and (3) adding the inorganic binder to the solution of organic binder, and blend. Additional reagents, such as a surfactant, may also be incorporated into the sorbent material. The present invention also provides a process for desulfurizing a gaseous stream. The process includes passing a gaseous stream through a reactor containing an attrition resistant zinc titanate sorbent material of the present invention.

  18. The Tides of Titan

    NASA Astrophysics Data System (ADS)

    Iess, L.; Jacobson, R.; Ducci, M.; Stevenson, D. J.; Lunine, J. I.; Armstrong, J. W.; Asmar, S.; Racioppa, P.; Rappaport, N. J.; Tortora, P.

    2012-12-01

    Titan has long been thought to host a subsurface water ocean. A liquid water or water-ammonia layer underneath the outer icy shell was invoked to explain the Voyager and Cassini observations of abundant methane (an easily dissociated species) in the atmosphere of the satellite. Given the paucity of surface hydrocarbon reservoirs, the atmospheric methane must be supplied by the interior, and an ocean can both provide a large storage volume and facilitate the outgassing from the deeper layers of the satellite to the surface. Huygens probe observations of a Schumann-like resonance point to the presence of an electrically conductive layer at a depth of 50-100 km, which has been interpreted to be the top of an ammonia-doped ocean [1]. Cassini gravity observations provide stronger evidence of the existence of such subsurface ocean. By combining precise measurements of the spacecraft range rate during six flybys, suitably distributed along Titan's orbit (three near pericenter, two near apocenter one near quadrature), we have been able to determine the k2 Love number to be k2 = 0.589±0.150 and k2 = 0.637±0.224 in two independent so-lutions (quoted uncertainties are 2-sigma) [2]. Such a large value indicates that Titan is highly deformable over time scales of days, as one would expect if a global ocean were hidden beneath the outer icy shell. The inclusion of time-variable gravity in the solution provided also a more reliable estimate of the static field, including an updated long-wavelength geoid. We discuss the methods adopted in our solutions and some implications of our results for the interior structure of Titan, and outline the expected improvements from the additional gravity flybys before the end of mission in 2017. [1] C. Beghin, C. Sotin, M. Hamelin, Comptes Rendue Geoscience, 342, 425 (2010). [2] L. Iess, R.A. Jacobson, M. Ducci, D.J. Stevenson, J.I. Lunine, J.W. Armstrong, S.W. Asmar, P. Racioppa, N.J. Rappaport, P. Tortora, Science, 337, 457 (2012).

  19. Titan Airship Surveyor

    NASA Technical Reports Server (NTRS)

    Kerzhanovich, V.; Yavrouian, A.; Cutts, J.; Colozza, A.; Fairbrother, D.

    2001-01-01

    Saturn's moon Titan is considered to be one of the prime candidates for studying prebiotic materials - the substances that precede the formation of life but have disappeared from the Earth as a result of the evolution of life. A unique combination of a dense, predominantly nitrogen, atmosphere (more than four times that of the Earth), low gravity (six times less than on the Earth) and small temperature variations makes Titan the almost ideal planet for studies with lighter-than-air aerial platforms (aerobots). Moreover, since methane clouds and photochemical haze obscure the surface, low-altitude aerial platforms are the only practical means that can provide global mapping of the Titan surface at visible and infrared wavelengths. One major challenge in Titan exploration is the extremely cold atmosphere (approx. 90 K). However, current material technology the capability to operate aerobots at these very low temperatures. A second challenge is the remoteness from the Sun (10 AU) that makes the nuclear (radioisotopic) energy the only practical source of power. A third challenge is remoteness from the Earth (approx. 10 AU, two-way light-time approx. 160 min) which imposes restrictions on data rates and makes impractical any meaningful real-time control. A small-size airship (approx. 25 cu m) can carry a payload approximately 100 kg. A Stirling engine coupled to a radioisotope heat source would be the prime choice for producing both mechanical and electrical power for sensing, control, and communications. The cold atmospheric temperature makes Stirling machines especially effective. With the radioisotope power source the airship may fly with speed approximately 5 m/s for a year or more providing an excellent platform for in situ atmosphere measurements and a high-resolution remote sensing with unlimited access on a global scale. In a station-keeping mode the airship can be used for in situ studies on the surface by winching down an instrument package. Floating above the surface allows relatively simple means for flight control. Mission requirements and possible methods of navigation, control, data acquisition, and communications are discussed. The presentation describes also the state-of-the art and current progress in aerial deployed aerobots.

  20. Titan's Carbon Conundrum

    NASA Astrophysics Data System (ADS)

    Nixon, C. A.; Jennings, D. E.; Teanby, N. A.; Vinatier, S.; BÉ Zard, B.; Coustenis, A.; Irwin, P. G.; Flasar, F. M.; Cassini Cirs Team

    2010-12-01

    As recently as a year ago, a consensus was emerging that carbon-13 in Titan's methane was enriched by some ~10% over the terrestrial value (12C/13C = ~77-82 on Titan versus 89 on Earth, Niemann et al 2005, Nixon et al 2008). At the same time, several measurements of 12C/13C in ethane, the main product of methane photolysis, appeared to show no enrichment (Nixon et al 2008, Jennings et al 2009). This led to the suggestion that a steady state equilibrium was being reached, with a Kinetic Isotope Effect (KIE) in a key reaction (C2H + CH4 ? C2H2 + CH3) responsible for the slight enrichment in the atmospheric reservoir relative to both the incoming flux of methane and outgoing flux of ethane (Jennings et al 2009). This paradigm was overturned earlier this year when the Huygens GCMS team revised their measurement of 12CH4/13CH4 upwards to agree with the terrestrial value (Niemann et al, in preparation), eliminating any need for the KIE fractionation. However, this presents a new problem in the sense that the KIE effect is probably real - it is confirmed for the CH3D and 12CH4 reactions with ethynyl (Opansky and Leone 1996), so almost certainly for 13CH4-12CH4 pair as well - and so some fractionation of methane should be occurring. This is true regardless as to whether the atmospheric methane is being replenished or not - differing only in degree - provided the ethynyl abstraction reaction is the dominant path for methane loss as predicted by current models (Lavvas et al. 2008). In this forum we will present updated measurements by the CIRS team of the 12CH4/13CH4 derived from recent high signal-to-noise Titan observations, and discuss the degree of agreement with both the earlier published ratios, and the newer revised GCMS results. We will also discuss the implications for Titan's methane evolution over geologic time including clues from the D/H ratio. We conclude by highlighting the currently open questions and avenues for future work. Jennings, D.E. et al., J. Chem. Phys., 113(42), 11101-11106, 2009. Lavvas, P.P. et al., Plan. Space Science, 56, 27-66, 2008. Niemann, H.B. et al., Nature, 438, 779-784, 2005. Nixon, C.A. et al., Icarus, 195, 778-791, 2008. Opansky, B.J and S.R. Leone, J. Phys. Chem., 100, 4888-4892, 1996.

  1. r Journalof Geology LATE ARCHEAN ZIRCON AGES 419

    E-print Network

    Mojzsis, Stephen J.

    #12;#12;#12;#12;#12;#12;#12;#12;#12;#12;#12;#12;r Journalof Geology LATE ARCHEAN ZIRCON AGES 419 0 25 Th/U signature,consonantwith zircons in Ch Zr low Th/U 3, and zircons of this ageand Th.164 nothingelseseemsextraordinaryaboutthe bulk composition or mineralogy. The preservationof someold zircons through the profoundhigh

  2. Damage detection in composite plates with embedded PZT transducers

    Microsoft Academic Search

    P. Kudela; W. Ostachowicz; A. ?ak

    2008-01-01

    This paper presents a concept of a structural health monitoring system based on PZT transducers. Taking advantage of spectral element method simulations of A0 mode of the Lamb waves propagating in a multilayer composite plate have been carried out. Based on obtained signals for a clock-like configuration of sensors, a damage detection algorithm has been proposed. The results for the

  3. Integration of zircon color and zircon fission-track zonation patterns in orogenic belts: application to the

    E-print Network

    Garver, John I.

    Integration of zircon color and zircon fission-track zonation patterns in orogenic belts, but are greenschist to amphibolite facies of the Alpine Schist. Zircon crystals from sediments in east-flowing rivers-damaged grains (up to 60%). These zircons are derived from the upper f 10 km crustal section (unreset FT color

  4. Touchdown on Titan

    NASA Technical Reports Server (NTRS)

    Morring, Frank, Jr.

    2004-01-01

    Europe's Huygens probe is on target for a Dec. 25 separation from the Cassini Saturn orbiter that has carried it like a baby for more than seven years. The probe will spend three weeks coasting to a plunge into Titan's thick atmosphere on the morning of Jan. 14. If all goes as planned, the 349-kg. Huygens will spend more than 2 hr. descending by parachute to the mysterious surface of the planet-sized moon, and hopefully devote yet more time to broadcasting data after it lands. Before the day is over, Huygens is programmed to beam about 30 megabytes of data - including some 1,100 images-back to Earth through Cassini, a trip that will take some 75 min. to complete over the 1- billion-km. distance that separates the two planets. Within that data should be answers to questions that date back to 1655, when Dutch astronomer Christiaan Huygens found the moon with a homemade telescope and named it for the family of giants the ancient Greeks believed once ruled the earth. In the Solar System, there is no other world like Titan, with a nitrogen and methane atmospheric and a cold, hidden surface darker than Earth under the full Moon.

  5. Titan's Gravitational Field

    NASA Astrophysics Data System (ADS)

    Schubert, G.; Anderson, J. D.

    2013-12-01

    Titan's gravitational field is inferred from an analysis of archived radio Doppler data for six Cassini flybys. The analysis considers each flyby separately in contrast to the approach of lumping all the data together in a massive inversion. In this way it is possible to gain an improved understanding of the character of each flyby and its usefulness in constraining the gravitational coefficient C22 . Though our analysis is not yet complete and our final determination of C22 could differ from the result we report here by 1 or 2 sigma, we find a best-fit value of C22 equal to (13.21 × 0.17) × 10-6, significantly larger than the value of 10.0 × 10-6 obtained from an inversion of the lumped Cassini data. We also find no determination of the tidal Love number k2. The larger value of C22 implies a moment of inertia factor equal to 0.3819 × 0.0020 and a less differentiated Titan than is suggested by the smaller value. The larger value of C22 is consistent with an undifferentiated model of the satellite. While it is not possible to rule out either value of C22 , we prefer the larger value because its derivation results from a more hands on analysis of the data that extracts the weak hydrostatic signal while revealing the effects of gravity anomalies and unmodeled spacecraft accelerations on each of the six flybys.

  6. Inflight dissociation of zircon in air plasma

    NASA Astrophysics Data System (ADS)

    Yugeswaran, S.; Ananthapadmanabhan, P. V.; Thiyagarajan, T. K.; Selvarajan, V.; Nair, Janardhanan

    2010-02-01

    Thermal dissociation of zircon can be conveniently carried out in a plasma reactor, which is characterized by high temperature, high energy density and high quench rate. Zirconia is recovered from this partially dissociated zircon by alkali leaching. Dissociation of zircon has been conventionally carried out in argon gas, which is expensive. The present paper reports experimental results on thermal dissociation of zircon in air plasma medium. Process simulation for 'inflight' dissociation of zircon in air plasma medium is also presented. The experimental system consists of a central hollow graphite electrode, which acts as the cathode and a graphite anode. The material to be processed is fed centrally through the cathode. The unique feature of the system is that it uses air as the working gas to generate the thermal plasma. The system has been used to study in-flight dissociation of zircon in the thermal plasma jet. Dissociation was carried out over 10-25 kW power range. Results of the study indicate that complete dissociation of zircon to ZrO2 and silica could be accomplished at 25 kW in air plasma.

  7. Titan Recreation-Intramural Sports Student Engagement Report

    E-print Network

    de Lijser, Peter

    Titan Recreation-Intramural Sports Student Engagement Report FY 2010-2011 Purpose Statement Titan and overall wellness. Titan Recreation also provides opportunities for cooperative and competitive play, team building and interpersonal skills. Leadership and participation opportunities within Titan

  8. Titan Recreation-Group Fitness Student Engagement Report

    E-print Network

    de Lijser, Peter

    Titan Recreation-Group Fitness Student Engagement Report FY 2012-2013 Purpose Statement Titan fitness and overall wellness. Titan Recreation also provides opportunities for cooperative and competitive within Titan Recreation are designed to enhance social, psychological and physiological development

  9. Titan Recreation-Intramural Sports Student Engagement Report

    E-print Network

    de Lijser, Peter

    Titan Recreation-Intramural Sports Student Engagement Report FY 2012-2013 Purpose Statement Titan fitness and overall wellness. Titan Recreation also provides opportunities for cooperative and competitive within Titan Recreation are designed to enhance social, psychological and physiological development

  10. Titan Recreation-Intramural Sports Student Engagement Report

    E-print Network

    de Lijser, Peter

    Titan Recreation-Intramural Sports Student Engagement Report FY 2011-2012 Purpose Statement Titan fitness and overall wellness. Titan Recreation also provides opportunities for cooperative and competitive within Titan Recreation are designed to enhance social, psychological and physiological development

  11. Elastic softening of zircon by radiation damage

    SciTech Connect

    Salje, Ekhard K. H. [Department of Earth Sciences, University of Cambridge, Downing Street, Cambridge CB2 3EQ (United Kingdom)

    2006-09-25

    The bulk modulus and the shear modulus of zircon soften by ca. 50% when zircon is amorphized by radiation damage. A theoretical description of the experimental findings is presented which shows that the elastic response on a zircon ceramics with radiation damage follows Hashin-Shtrikman [J. Mech. Phys. Solids 11, 127 (1963)] behavior with very narrow bounds. The elastic response depends, in good approximation, on the square of the volume fraction f{sub a} of the amorphized regions. In a slightly coarser approximation one finds an almost linear interpolation of the bulk and the shear modulus between those of the crystalline state and those of the fully amorphous state.

  12. Solution Synthesis and Processing of PZT Materials for Neutron Generator Applications

    SciTech Connect

    Anderson, M.A.; Ewsuk, K.G.; Montoya, T.V.; Moore, R.H.; Sipola, D.L.; Tuttle, B.A.; Voigt, J.A.

    1998-12-01

    A new solution synthesis route has been developed for the preparation of lead-based ferroelectric materials (patent filed). The process produces controlled stoichiometry precursor powders by non-aqueous precipitation. For a given ferroelectric material to be prepared, a metal acetate/alkoxide solution containing constituent metal species in the appropriate ratio is mixed with an oxalic acid/n-propanol precipitant solution. An oxalate coprecipitate is instantly fonned upon mixing that quantitatively removes the metals from solution. Most of the process development was focused on the synthesis and processing of niobium-substituted lead zirconate titanate with a Zr-to-Ti ratio of 95:5 (PNZT 95/5) that has an application in neutron generator power supplies. The process was scaled to produce 1.6 kg of the PNZT 95/5 powder using either a sen-ii-batch or a continuous precipitation scheme. Several of the PNZT 95/5 powder lots were processed into ceramic slug form. The slugs in turn were processed into components and characterized. The physical properties and electrical performance (including explosive functional testing of the components met the requirements set for the neutron generator application. Also, it has been demonstrated that the process is highly reproducible with respect to the properties of the powders it produces and the properties of the ceramics prepared from its powders. The work described in this report was funded by Sandia's Laboratory Directed Research and Development Program.

  13. The TITAN reversed-field-pinch fusion reactor study

    SciTech Connect

    Not Available

    1990-01-01

    This report discusses research on the titan-1 fusion power core. The major topics covered are: titan-1 fusion-power-core engineering; titan-1 divertor engineering; titan-1 tritium systems; titan-1 safety design and radioactive-waste disposal; and titan-1 maintenance procedures.

  14. Zirconate pyrochlores under high pressure

    SciTech Connect

    Xiao, Haiyan Y.; Zhang, F. X.; Gao, Fei; Lang, Maik; Ewing, Rodney C.; Weber, William J.

    2010-07-12

    Ab initio total-energy calculations and x-ray diffraction measurements have been combined to study the phase stability of zirconate pyrochlores (A2Zr2O7; A=La, Nd and Sm) under pressures up to 50 GPa. Phase transformations to the defect-cotunnite structure are theoretically predicted at pressures of 22, 20 and 18 GPa, in excellent agreement with the experimentally determined values of 21, 22 and 18 GPa for La2Zr2O7, Nd2Zr2O7 and Sm2Zr2O7, respectively. Analysis of the elastic properties indicates that elastic anisotropy may be one of the driving forces for the pressure-induced cubic-to-noncubic phase transformation.

  15. Refractory Materials of Zirconate. Part 2: Synthesis and some properties of strontium, zirconate, calcium zirconate and barium zirconate

    NASA Technical Reports Server (NTRS)

    Okubo, Tsutomo; Yonemochi, Osamu; Nakamura, Kazuo; Maeda, Minoru

    1988-01-01

    Chemical compounds SrZrO3, CaZrO3, and BaZrO3 were synthesized by solid reaction and arc fusion, and their properties examined. Results were as follows: (1) in the synthesis of CaZrO3 by solid reaction, ZrO2 solid solution with cubic form was produced, which then changed into CaZrO3; (2) the BaZrO3 was a cubic form and did not show any transformation, while SrZrO3 and CaZrO3 with an orthorhombic form transformed to a cubic form at high temperature; and (3) the solubility of BaZrO3 in acid and its vaporization rate at a high temperature were greater than those of zirconates.

  16. Titan's rotation - Surface feature observed

    NASA Astrophysics Data System (ADS)

    Lemmon, M. T.; Karkoschka, E.; Tomasko, M.

    1993-06-01

    A surface feature or a near-surface fracture is suggested to account for the time variations in the 0.94, 1.08, and 1.28 micron atmospheric windows of Titan's geometric albedo, relative to its albedo in adjacent methane bands. These observations are noted to be consistent with synchronous rotation. They can also be explained by a 0.1-higher surface albedo on Titan's leading hemisphere.

  17. NOVA Online: Titanic's Lost Sister

    NSDL National Science Digital Library

    Companion site to an original broadcast on January 28, 1997. When Titanic sank, construction on her sister ship, Britannic, was interrupted so she could be overhauled with new regulations. Britannic sank in 1916 in less than an hour. Includes interview with Robert Ballard, who found the sunken Titanic, an interactive search, and salvage activity. Others resources available: written transcript, teacher's guide, students activities, and links to additional resources.

  18. From Titan's chemistry and exobiology to Titan's astrobiology

    NASA Astrophysics Data System (ADS)

    Raulin, François

    2015-04-01

    When the IDS proposal « Titan's chemistry and exobiology » was submitted to ESA 25 years ago, in the frame of what will become the Cassini-Huygens mission, Titan was already seen as a quite interesting planetary object in the solar system for Exobiology. Several organic compounds of prebiotic interest were identified in its atmosphere, which was thus was expected to be chemically very active, especially in term of organic processes. Atmospheric aerosols seemed to play a key role in this chemistry. Moreover, the presence of an internal aqueous ocean, compatible with life was suspected. A few years later, when astrobiology was (re)invented, Titan became one of the most interesting planetary target for this new (but very similar to exobiology) field. With the Cassini-Huygens mission, the exo/astrobiological interest of Titan has become more and more important. However, the mission has been providing a vision of Titan quite different from what it was supposed. Its atmospheric organic chemistry is very complex and starts in much higher zones than it was believed before, involving high molecular weight species in the ionosphere. Titan's surface appears to be far from homogeneous: instead of been covered by a global methane-ethane ocean, it is very diversified, with dunes, lakes, bright and dark areas, impact and volcanic craters with potential cryovolcanic activity. These various geological areas are continuously feeded by atmospheric aerosols, which represent an important step in the complexity of Titan's organic chemistry, but probably not the final one. Indeed, after being deposited on the surface, in the potential cryovolvanic zones, these particles may react with water ice and form compounds of exo/astrobiological interest, such as amino acids, purine and pyrimidine bases. Moreover, The Cassini-Huygens data strongly support the potential presence of an internal water ocean, which becomes less and less hypothetical and of great interest for exobiology. These various exobiological aspects of Titan, revealed from Cassini-Huygens observations, especially from the data of the Huygens instruments, coupled to laboratory works, both experimental simulations and modeling, will be quickely reviewed and summarized. References : Raulin, F. (2008), Astrobiology and habitability of Titan, Space Science Reviews 135 (1-4), 37-48 ; Raulin, F. et al. (2012), Prebiotic-like chemistry on Titan. Chemical Society Reviews. 41, 5380-5393 Acknowledgement: Supports from the European Space Agency (ESA) and the French Space Agency (CNES) is deeply acknowledged.

  19. Isotopic Composition of Oxygen in Lunar Zircons

    NASA Technical Reports Server (NTRS)

    Nemchin, A. A.; Whitehouse, M. J.; Pidgeon, R. T.; Meyer, C.

    2005-01-01

    The recent discovery of heavy oxygen in zircons from the Jack Hills conglomerates Wilde et al. and Mojzsis et al. was interpreted as an indication of presence of liquid water on the surface of Early Earth. The distribution of ages of Jack Hills zircons and lunar zircons appears to be very similar and therefore analysis of oxygen in the lunar grains may provide a reference frame for further study of the early history of the Earth as well as give additional information regarding processes that operated on the Moon. In the present study we have analysed the oxygen isotopic composition of zircon grains from three lunar samples using the Swedish Museum of Natural History CAMECA 1270 ion microprobe. The samples were selected as likely tests for variations in lunar oxygen isotopic composition. Additional information is included in the original extended abstract.

  20. The TITAN magnet configuration

    SciTech Connect

    Bathke, C.G.

    1987-01-01

    The TITAN study uses copper-alloy ohmic-heating coils (OHC) to startup inductively a reversed-field-pinch (RFP) fusion reactor. The plasma equilibrium is maintained with a pair of superconducting equilibrium-field coils (EFCs). A second pair of copper EFCs provides the necessary trimming of the equilibrium field during plasma transients. A compact toroidal-field-coil (TFC) set is provided by an integrated blanket/coil (IBC). The IBC concept also is applied to the toroidal-field divertor coils. Steady-state operation is achieved with oscillating-field current drive, which oscillates at low amplitude and frequency the OHCs, EFCs, the TFCs, and divertor coils about their steady-state currents. An integrated magnet design, which uses low-field, low technology coils, and the related design basis is given. 18 refs.

  1. Life on Titan

    NASA Astrophysics Data System (ADS)

    Potashko, Oleksandr

    Volcanoes engender life on heavenly bodies; they are pacemakers of life. All planets during their period of formation pass through volcanism hence - all planets and their satellites pass through the life. Tracks of life If we want to find tracks of life - most promising places are places with volcanic activity, current or past. In the case of just-in-time volcanic activity we have 100% probability to find a life. Therefore the most perspective “search for life” are Enceladus, Io and comets, further would be Venus, Jupiter’s satellites, Saturn’s satellites and first of all - Titan. Titan has atmosphere. It might be result of high volcanic activity - from one side, from other side atmosphere is a necessary condition development life from procaryota to eucaryota. Existence of a planet means that all its elements after hydrogen formed just there inside a planet. The forming of the elements leads to the formation of mineral and organic substances and further to the organic life. Development of the life depends upon many factors, e.g. the distance from star/s. The intensity of the processes of the element formation is inversely to the distance from the star. Therefore we may suppose that the intensity of the life in Mercury was very high. Hence we may detect tracks of life in Mercury, particularly near volcanoes. The distance from the star is only one parameter and now Titan looks very active - mainly due to interior reason. Its atmosphere compounds are analogous to comet tail compounds. Their collation may lead to interesting result as progress occurs at one of them. Volcanic activity is as a source of life origin as well a reason for a death of life. It depends upon the thickness of planet crust. In the case of small thickness of a crust the probability is high that volcanoes may destroy a life on a planet - like Noachian deluge. Destroying of the life under volcano influences doesn’t lead to full dead. As result we would have periodic Noachian deluge or nuclear winter. These events are known as extinctions or ice ages. The crust of a planet of the Earth group is formed at the outer edge of the body. The planets after asteroid belt like Jupiter or Saturn probably form their “crusts” in the centre of the body. Due to we may see internal kitchen of element forming in detail. This processes lead to the organic life, which we may detect at the atmospheres of Jupiter, Saturn, Neptune, and Pluto. But their satellites look like earth planet group - with outer crust. Huygens considered that God's wisdom and providence is clearest in the creation of life, and Earth holds no privileged position in the heavens that life must be universal. “Huygens” helps find life on Titan

  2. Detrital Zircon Geochronology Applied to Basin Analysis

    NASA Astrophysics Data System (ADS)

    Gehrels, G. E.

    2014-12-01

    During the past ~15 years, detrital zircon geochronology has developed into a powerful tool for analyzing sedimentary features and processes. One of the most common applications is to use the ages of the youngest detrital zircons in a sample to constrain the maximum age of deposition. In an ideal case, for example in a region with active volcanism, the youngest zircon grains would have crystallized immediately prior to deposition and the lag time between crystallization and deposition is negligible. Such ages provide opportunities for reconstructing the chrono-stratigraphy of a sedimentary sequence, and establishing the chrono-correlation of sedimentary units and surfaces across broad regions. Most sedimentary units also yield detrital zircon grains that significantly predate deposition (because of the extreme durability of zircon). The ages of these grains provide a fingerprint (or chrono-facies) that can be used for comparison of sedimentary units. Such comparisons have traditionally been based on the presence/absence of age populations, but with larger data sets it is becoming possible to determine proportions of ages in a robust fashion, and thereby compare strata much more quantitatively. Common methodology for conducting these types of analyses is to determine ages for several hundred detrital zircon grains from each sample, with random selection of grains to generate a robust age distribution. If necessary, additional analyses are conducted on "young-looking" grains to improve precision on the max depo age. Such analyses commonly yield max depo ages that are reliable to 1-2%. Determining whether a max depo age approximates true depo age commonly requires geologic arguments (e.g., presence of volcanic lithic fragments, size/shape of the youngest zircon crystals, order of youngest ages in a sedimentary sequence). In addition to these chronologic applications, detrital zircon ages provide powerful tools for determining provenance, reconstructing dispersal pathways (commonly involving episodes of recycling), characterizing source regions, establishing connections between drainage areas and offshore basins, and evaluating reservoir characteristics.

  3. Synthesis of zircon for immobilization of actinides

    SciTech Connect

    Burakov, B.E.; Anderson, E.B.; Rovsha, V.S.; Ushakov, S.V. [Khlopin Radium Inst., St. Petersburg (Russian Federation); Ewing, R.C.; Lutze, W. [Univ. of New Mexico, Albuquerque, NM (United States); Weber, W.J. [Pacific Northwest National Lab., Richland, WA (United States)

    1996-08-01

    A new method of synthesis for actinide-doped zircon is presented based on studies of zircons formed by crystallization from the reactor core melt generated in the course of the accident at the Chernobyl Nuclear Power Plant. These zircons have compositions in the range (Zr{sub 0.94}, U{sub 0.06})SiO{sub 4} to (Zr{sub 0.9}, U{sub 0.1})SiO{sub 4}. Hot-pressing of oxides was studied to make Zr-based waste forms. The results demonstrate the efficacy of using metallic zirconium in synthesizing high-actinide zircons. In the event of deviations from zircon`s ideal stoichiometry, ZrO{sub 2} forms, which is also an effective host phase for actinide elements. Waste streams high in zirconium and actinides could be converted into Zr-based waste forms. The adaptation and modification of the mixed-oxide reactor fuel (MOX) production process is proposed as a process for the production of (Zr,Pu)SiO{sub 4}, a durable waste form for excess weapons plutonium.

  4. The role of photochemistry in Titan’s atmospheric chemistry

    NASA Astrophysics Data System (ADS)

    Ferris, James; Tran, Buu; Joseph, Jeffrey; Vuitton, Veronique; Briggs, Robert; Force, Michael

    Experimental studies were performed to simulate the action of long wavelength solar UV light on Titan's atmosphere. The experiments were carried out in a photochemical flow reactor using a mixture of gases representative of Titan's atmosphere at 70° north latitude (Titan's north pole) in the winter. The solid analog of Titan's haze formed has optical properties comparable to that determined for Titan's haze from modeling Voyager 1 data. Since the optical properties of the haze analogs formed by discharge reactions also have optical properties similar to Titan's haze. It was concluded that the variation in light absorption with wavelength of the haze in the UV-vis spectral region does not vary sufficiently to discriminate between different haze analogs. The C/N ratio of the haze analog prepared by UV radiation is in the 15-20 range while that formed by the action of magnetospheric electrons is in the 2-5 range. The infrared spectrum of the haze analog has absorption bands attributed to CH 3, CH 2, C dbnd CC tbnd N, C dbnd C and possibly N-H groups. The UV spectrum is consistent with the presence of double bonds and conjugated double bonds. No polycyclic aromatic compounds were detected. The volatile photoproducts mainly consist of saturated, olefinic and acetylenic hydrocarbons along with much smaller amounts of benzene and substituted benzenes. Among these volatiles hydrogen cyanide is probably the most abundant nitrogen containing with much less acetonitrile, and trace amounts of acrylonitrile. Some of these volatiles will condense on haze particles at the temperatures and pressures on Titan. The comparison of the volatiles formed by UV radiations are compared with those formed by three different discharges.

  5. TITAN Overview 1 TITAN: A NextGeneration Infrastructure for Integrating

    E-print Network

    California at Berkeley, University of

    TITAN Overview 1 TITAN: A Next­Generation Infrastructure for Integrating Computing and communication infrastructure a new type of computing system, called Titan. This computing system comprises be examined on­line at URL http://www.cs/projects/titan/index.html In this report we outline the progress

  6. The Surface Composition of Titan

    NASA Astrophysics Data System (ADS)

    Clark, R. N.; Pearson, N.; Brown, R. H.; Cruikshank, D. P.; Barnes, J. W.; Jaumann, R.; Soderblom, L. A.; Griffith, C. A.; Rodriguez, S.; Le Mouelic, S.; Lunine, J.; Sotin, C.; Baines, K. H.; Buratti, B. J.; Nicholson, P. D.; Nelson, R.; Stephan, K.

    2011-12-01

    Determining the surface composition of Titan has been inhibited by the lack of spectral properties of potential compounds. We have measured the 0.35 to 5-micron spectral reflectance of a wide range of compounds that might be relevant to Titan and trends are now coming to light with possible spectral matches for classes of materials. While some compounds have been identified and mapped on Titan's surface, such as liquid ethane + methane lakes and benzene, the compounds responsible for the main spectral properties have remained elusive (Clark et al, JGR 2010). Titan's surface is seen in the near infrared in only a few spectral windows, near 0.94, 1.1, 1.3, 1.6, 2.0, 2.68-2.78, and 4.9-5.1 microns in the Cassini Visual and Infrared Mapping Spectrometer (VIMS) spectral range. At shorter wavelengths, UV absorption in the spectra of Titan's haze constrains the surface composition because haze particles settle onto Titan's surface. The average apparent reflectance in the IR windows generally decreases with increasing wavelength except for the 2.7 and 5-micron windows which are at similar levels. The decrease has led researchers to infer a number of compounds responsible for the observed decreasing spectral shape; the most common being water ice. But ice is incompatible with the 2.78/2.68 micron I/F ratio. Many organic compounds have absorptions that are not seen in spectra of Titan, eliminating them as possible major components at the surface, including many polycyclic aromatic hydrocarbons (PAH) previously thought to be compatible with parts of Titan's spectrum. We find that ring compounds similar to benzene rings, but with some C-H bonds replaced by NH have a closer match to Titan's overall spectrum and can explain the relative intensities observed in the spectral windows, including the 2.68 and 2.78-micron double window, the low 3-5 micron reflectance, and increased absorption near 2.1-microns. Key among these compounds that show general properties that match Titan are Cytosine (C4H5N3O), Uracil (C4H4N2O2), Guanine (C5H5N5O), and Adenine (C5H5N5). These compounds are the four nucleobases in the nucleic acid of RNA. If these compounds can be confirmed to be on Titan, their formation pathways may have implications for the formation of life. Other compounds that match features in Titan's spectra include the polycyclic aromatic hydrocarbon (PAH) coronene, consisting of 6 benzene rings. Coronene is also a naturally occurring mineral on Earth, known as karpatite. Combinations of coronene, phenanthene (C14H12), pentacene (C22H14), indole (C8H7N), Cytosine, Uracil, Guanine, and Adenine match the overall spectral structure of Titan spectra. Indole, Cytosine, and Uracil, have 1.5-micron bands that can explain the feature observed in DISR spectra of Titan's surface. These compounds can also help explain the pyrolysis results from the Huygens probe.

  7. Titan, Weird Chemistry, and Weird Life

    NASA Astrophysics Data System (ADS)

    Benner, S. A.; Kim, H.-J.

    2010-04-01

    Some hypothesize that life arises with high probability in complex chemical systems. Titan's methane and ammonia-water liquids are accessible to test this. Laboratory work is developing possible metabolisms and genetic systems in Titans.

  8. Simulation of thick film PZT actuators with interdigitated electrodes

    NASA Astrophysics Data System (ADS)

    Zaki, Mohanad M.; Zähringer, Sandy; Schwesinger, Norbert

    2013-05-01

    This paper deals with the simulation of membrane actuators based on thick film piezoelectric ceramics with interdigitated electrodes using the finite element method. A modified piezoelectric coupling matrix is introduced to account for the piezoelectric non-linearity due to poling and actuation at high electric fields. Electrodes were fabricated on top of 250 ?m thick PZT substrates which were characterized. The experimental data verified the simulation results and proved the necessity of the modified coupling matrix.

  9. Primary Pyroelectric Effect in the PZT 95?5 Ceramic

    Microsoft Academic Search

    J. L. Wentz; L. Z. Kennedy

    1964-01-01

    An expression of the thermodynamic potential is examined in terms of the primary and secondary pyroelectric coefficients of a poled ferroelectric ceramic. Anisotropic expansion and zero electric field conditions are assumed. The pyroelectric coefficient is applied to the composition, Pb(Zr0.95Ti0.05)O3 (PZT 95?5) with 1 wt. % of Nb2O5, for which a complete set of elastic, piezoelectric, thermoelastic, and pyroelectric coefficients

  10. Synthesis of Tube-Like PZT Nanostructures by Sol-Gel Process

    NASA Astrophysics Data System (ADS)

    Acharya, S. A.; Singh, K.

    2011-11-01

    In the present work, we report the synthesis of PZT in tubes-like nanostructure by microwave-assisted sol-gel route. According to our knowledge, this is the first report on tubes-like PZT, were obtained by microwave-assisted sol-gel route. To understand the effect of microwave heating on the synthesis, the same experiment was repeated by using conventional way of heating. Round shape nanoparticles of PZT were obtained by the conventional sol-gel route. The crystallization behaviors of the tubes and nanoparticles of PZT are confirmed by XRD. The structural morphologies of the PZT sample are observed by SEM and TEM. The thermal decomposition characteristics of the gel are identified by DTA and TGA. The molecular structures are investigated by FTIR. A pure pervoskite PZT powders were obtained after having been annealed tubes-like structure at 650 °C and NPs at 750 °C for 3 hr.

  11. Influence of fatigue processes on the switching currents in lead titanate and lead zirconate-titanate films

    NASA Astrophysics Data System (ADS)

    Sidorkin, A. S.; Nesterenko, L. P.; Pakhomov, A. Yu.

    2012-05-01

    The processes of polarization fatigue in PbTiO3 and Pb(Zr0.5Ti0.5)O3 films on silicon substrates have been studied by the method of switching in rectangular pulsed fields. Dependences of the switchable polarization, the maximum switching current i max, and the switching time ? s on the number of switching cycles have been obtained from the data on the switching currents. It has been shown that the mobility of domain walls is retained in the fatigue processes and the observed fatigue is connected with switching off a fraction of the switchable volume due to pinning of reverse domain nuclei by charged defects.

  12. Mesoscale Circulations over Titan's Lakes

    NASA Astrophysics Data System (ADS)

    Soto, Alejandro; Rafkin, Scot

    2015-04-01

    The formation and duration of the Titan lakes are dependent on the balance of precipitation and evaporation in the Titan climate. It appears that the seasonal variations of insolation combine with the slow planetary rotation rate to generate a climate where the bulk of precipitation is confined to the polar regions and transient storm activity occurs in the equatorial and mid-latitude regions. Numerous studies have already investigated how large-scale atmospheric dynamics contributes to this precipitation and evaporation cycle. Some of these studies used two and three dimensional general circulation models (GCMs) that employed parameterizations to capture the near surface evaporation and convective processes. The GCM parameterizations of evaporation and convection parameterizations inevitably fail to capture in detail the evaporation and precipitation processes that occur over the hydrocarbon lakes on Titan. To investigate these processes in detail, we used a mesoscale numerical model of the Titan atmosphere in order to assess the evaporation rates and convective activities over the Titan lakes. Our model was developed by modifying the mesoscale version of the Weather Research and Forecasting (WRF) atmospheric dynamics model. WRF has been extensively used to study mesoscale atmospheric dynamics on Earth, including the dynamics that develop over lakes, making it an ideal model for this type of investigation. For our use, Titan parameters were applied to the WRF model, including planetary size and atmospheric composition. Due to the long radiative timescale of the atmosphere of Titan and the length of our simulations, radiative transfer calculations were not included in the simulation. Idealized, two-dimensional simulations of lakes were simulated in order to understand evaporation rates as well as identify the types of circulations generated over the lakes. Here we present the results of this research.

  13. Hemispherical Constraint of Titan's Methane Cycle

    NASA Astrophysics Data System (ADS)

    Trafton, Laurence; Kim, Sang; Geballe, Thomas

    2014-02-01

    We propose to use Gemini with NIFS/Altair to map weak lines of methane and methal deuteride in Titan's 2-2.11 micron window in the Earth's K band window in order to probe the hemispherical (seasonal) variation of the methane column abundance in Titan's atmosphere and thereby constrain its seasonal transport. The results will help to clarify whether volatile, high-latitude lakes drive a global-scale methane cycle in Titan's atmosphere and to constrain GCM models of Titan.

  14. The atmospheric temperature structure of Titan

    NASA Technical Reports Server (NTRS)

    Mckay, Christopher P.; Pollack, J. B.; Courtin, Regis; Lunine, Jonathan I.

    1992-01-01

    The contribution of various factors to the thermal structure of Titan's past and present atmosphere are discussed. A one dimensional model of Titan's thermal structure is summarized. The greenhouse effect of Titan's atmosphere, caused primarily by pressure induced opacity of N2, CH4, and H2, is discussed together with the antigreenhouse effect dominated by the haze which absorbs incident sunlight. The implications for the atmosphere of the presence of an ocean on Titan are also discussed.

  15. Tidal Winds on Titan Caused by Saturn

    Microsoft Academic Search

    Tetsuya Tokano; Fritz M. Neubauer

    2002-01-01

    The influence of Saturn's gravitational tide on the atmosphere of Titan is investigated by means of a three-dimensional general circulation model. Titan's orbital eccentricity of 0.0292 gives rise to time-dependent radial and librational tide whose potential circles eastward on Titan. Unlike atmospheric tides on terrestrial planets, Saturn's tide on Titan has a large impact on the dynamic meteorology down to

  16. Properties of thick PZT films prepared by modified metal organic decomposition process

    Microsoft Academic Search

    Yi-Nein Lai; Cheng-Hsiung Lin; Hsiu-Fung Cheng; I-Nan Lin

    2001-01-01

    Characteristics of PZT films synthesized by using a modified metal-organic decompositions (MOD) process, which is the spin-coating of a nano-powder incorporated PZT carbaxylate solution, was examined. A deposition rate as large as 0.27 ? m per layer is achieved by carefully adjusting the concentration of carboxylate solution (0.4 M) and spin-coating process (2000 rpm). PZT films thus obtained possess good

  17. Assessment of PZT transducer bonding techniques under drop-weight impact loading in composites

    Microsoft Academic Search

    Kyle R. Mulligan; Pierre-Claude Ostiguy; Patrice Masson; Saïd Elkoun; Nicolas Quaegebeur

    2011-01-01

    This paper describes the robustness of a structural health monitoring system (SHM) that utilizes lead-zirconatetitanate (PZT) transducers tested on carbon fibre composite coupons under drop-weight impact loading. Four PZT transducers are attached to the surface of 10.16 cm x 15.24 cm aerospace grade carbon fibre coupons using four types of adhesives: cyanoacrylate, epoxy, methyl methacrylate, and silicon. Each PZT transducer

  18. Highly-efficient, flexible piezoelectric PZT thin film nanogenerator on plastic substrates.

    PubMed

    Park, Kwi-Il; Son, Jung Hwan; Hwang, Geon-Tae; Jeong, Chang Kyu; Ryu, Jungho; Koo, Min; Choi, Insung; Lee, Seung Hyun; Byun, Myunghwan; Wang, Zhong Lin; Lee, Keon Jae

    2014-04-23

    A highly-efficient, flexible piezoelectric PZT thin film nanogenerator is demonstrated using a laser lift-off (LLO) process. The PZT thin film nanogenerator harvests the highest output performance of ?200 V and ?150 ?A·cm(-2) from regular bending motions. Furthermore, power sources generated from a PZT thin film nanogenerator, driven by slight human finger bending motions, successfully operate over 100 LEDs. PMID:24523251

  19. Thinned-PZT on SOI process and design optimization for piezoelectric inertial energy harvesting

    Microsoft Academic Search

    Ethem Erkan Aktakka; Rebecca L. Peterson; Khalil Najafi

    2011-01-01

    This paper presents the design, fabrication, and testing of a thinned-PZT\\/Si unimorph for vibration energy harvesting. It produces a record power output and has state-of-the-art efficiency. The harvester utilizes thinning of bulk-PZT pieces bonded to an SOI wafer, and takes advantage of the similar thermal expansion between PZT and Si to minimize beam bending due to residual stress. Monolithic integration

  20. Fabrication and evaluation of 1.3 PZT fiber\\/epoxy composites

    Microsoft Academic Search

    H. S. Lee; C. Richard; A. Agbossu; J. Pastor; D. Guyomar

    2000-01-01

    1.3 composites were fabricated with PZT 5A fibers and a standard epoxy. The composites were simply obtained by natural packing of pre-coated PZT fibers in a mold. Fiber spacing and consequently PZT volume fraction is determined by the fiber coating thickness. A method allowing to control the epoxy coating thickness is proposed. Composite with volume fraction lying between 10 and

  1. Gemini Titan II Booster Electrical System

    Microsoft Academic Search

    Norman E. Sitter

    1966-01-01

    A description of the Gemini Titan II Launch Vehicle's redundant electrical system and differences between the electrical systems of the Titan II and Gemini Titan II Launch Vehicles are presented. Also described are the interfaces with the guidance\\/flight control, malfunction detection, range safety, hydraulic and instrumentation systems, and the interface of the launch vehicle and Gemini spacecraft. Principal electrical component

  2. Dunes on Titan observed by Cassini Radar

    Microsoft Academic Search

    J. Radebaugh; R. D. Lorenz; J. I. Lunine; S. D. Wall; G. Boubin; E. Reffet; R. L. Kirk; R. M. Lopes; E. R. Stofan; L. Soderblom; M. Allison; M. Janssen; P. Paillou; P. Callahan; C. Spencer

    2008-01-01

    Thousands of longitudinal dunes have recently been discovered by the Titan Radar Mapper on the surface of Titan. These are found mainly within ±30° of the equator in optically-, near-infrared-, and radar-dark regions, indicating a strong proportion of organics, and cover well over 5% of Titan's surface. Their longitudinal duneform, interactions with topography, and correlation with other aeolian forms indicate

  3. Dynamics of Titan's thermosphere H. Rishbetha, b,

    E-print Network

    Yelle, Roger V.

    Dynamics of Titan's thermosphere H. Rishbetha, b, *, R.V. Yellea , M. Mendilloa a Center for Space; accepted 23 June 1999 Abstract We estimate the wind speeds in Titan's thermosphere by considering, but in Titan's thermosphere they are mainly controlled by the nonlinear advection and curvature forces

  4. Congratulations to the 2011 Tech Titan Recipients

    E-print Network

    Chiao, Jung-Chih

    Congratulations to the 2011 Tech Titan Recipients Published Tuesday, September 13, 2011 6:00 am Eleven new Tech Titans were crowned and $11,000 was pledged for the MTBC STEM Partnership Fund at his year's annual Tech Titans Gala, held Friday, August 26 at the Hilton Anatole Hotel near downtown Dallas

  5. Applicant # Titan Student Centers Governing Board

    E-print Network

    de Lijser, Peter

    Applicant # Titan Student Centers Governing Board 2011-12 Application Packet General Information 1. The Titan Student Centers is a major program operated as part of the Associated Students, CSUF, Incorporated, and an on-campus non-profit organization serving the needs of CSU Fullerton students. The Titan Student

  6. 29 August 2011 2011 TECH TITAN

    E-print Network

    Chiao, Jung-Chih

    29 August 2011 2011 TECH TITAN Media Contact: Herb Booth, Office:817-272-7075, Cell:214 electrical engineering professor, a 2011 Tech Titan in the Technology Innovator category. The council has. The Tech Titans awards are in their 11 year of recognizing outstanding technology companies and North Texas

  7. Sputtering and heating of Titan's upper atmosphere

    E-print Network

    Johnson, Robert E.

    Sputtering and heating of Titan's upper atmosphere BY ROBERT E. JOHNSON 1,2,* 1 University, USA Titan is an important endpoint for understanding atmospheric evolution. Prior to Cassini's arrival ) and dominated by atmospheric sputtering. Recent analysis of the structure of Titan's thermosphere and corona

  8. Molecular Dynamics Simulation of Disordered Zircon

    SciTech Connect

    Devanathan, Ram; Corrales, Louis R.; Weber, William J.; Chartier, Alain; Meis, Constantin

    2004-02-27

    The melting of zircon and the amorphous state produced by quenching from the melt were simulated by molecular dynamics using a new partial charge model combined with the Ziegler-Biersack-Littmark potential. The model has been established for the description of the crystalline and aperiodic structures of zircon in order to be used for the simulation of displacement cascades. It provides an excellent fit to the structure, and accounts with convenient precision the mechanical and thermodynamic properties of zircon. The calculated melting temperature is about 2100 K. The activation energy for self-diffusion of ions in the liquid state was determined to be 190-200 kJ/mole. Melt quenching was employed to produce two different disordered states with distinct densities and structures. In the high density disordered state, the zircon structure is intact but the bond angle distributions are broader, 4% of the Si units are polymerized, and the volume swelling is about 8%. In the low density amorphous state, the Zr and Si coordination numbers are lower, and the Zr-O and Si-O bond lengths are shorter than corresponding values for the crystal. In addition, a highly polymerized Si network, with average connectivity of two, is observed in the low density amorphous state. These features have all been experimentally observed in natural metamict zircon. The present findings, when considered in light of experimental radiation effects studies, suggest that the swelling in zircon arises initially from disorder in the zircon crystal, and at high doses the disordered crystal is unable to accommodate the volume expansion and transforms to the amorphous state.

  9. Piezoelectric properties of 3-X periodic Pb(ZrxTi1-x)O3-polymer composites

    NASA Astrophysics Data System (ADS)

    Smay, James E.; Cesarano, Joseph; Tuttle, Bruce A.; Lewis, Jennifer A.

    2002-11-01

    The piezoelectric properties of lead zirconate titanate (PZT)-polymer composites were studied as a function of composition and phase connectivity. PZT skeletal structures were fabricated by robotic deposition, densified at 1275 °C, and subsequently infiltrated with epoxy to produce the desired PZT-polymer composites. These 3-X structures consisted of a three-dimensional lattice of PZT rods (3-3) embedded in a polymer matrix, a PZT lattice/polymer matrix capped with PZT face plates (3-2), or PZT lattice/polymer matrix capped with PZT face plates and encircled by a solid PZT ring (3-1). The PZT:polymer ratio was varied systematically by changing the lattice (rod) spacing in each composite architecture. The concentration of PZT pillars, which formed along the poling direction at the intersections between PZT rods, varied as the PZT volume fraction squared. These 3-X composites displayed enhanced hydrostatic figures of merit relative to monolithic PZT due to stress concentration in the PZT pillars and their dramatically reduced dielectric constant, with the highest values found for the 3-2 and 3-1 composites. Our experimental observations were compared to theoretical predictions based on an isostrain, unit cell model modified to account for the partial support of stress in the stiff epoxy phase.

  10. Radiation damage in zircon and monazite

    SciTech Connect

    Meldrum, A.; Boatner, L.A. [Oak Ridge National Lab., TN (United States). Solid state Div.] [Oak Ridge National Lab., TN (United States). Solid state Div.; Weber, W.J. [Pacific Northwest National Lab., Richland, WA (United States)] [Pacific Northwest National Lab., Richland, WA (United States); Ewing, R.C. [Univ. of Michigan, Ann Arbor, MI (United States). Dept. of Nuclear Engineering and Radiological Sciences] [Univ. of Michigan, Ann Arbor, MI (United States). Dept. of Nuclear Engineering and Radiological Sciences

    1998-07-01

    Monazite and zircon respond differently to ion irradiation and to thermal and irradiation-enhanced annealing. The damage process (i.e., elastic interactions leading to amorphization) in radioactive minerals (metamictization) is basically the same as for the ion-beam-irradiated samples with the exception of the dose rate which is much lower in the case of natural samples. The crystalline-to-metamict transition in natural samples with different degrees of damage, from almost fully crystalline to completely metamict, is compared to the sequence of microstructures observed for ion-beam-irradiated monazite and zircon. The damage accumulation process, representing the competing effects of radiation-induced structural disorder and subsequent annealing mechanisms (irradiation-enhanced and thermal) occurs at much higher temperatures for zircon than for monazite. The amorphization dose, expressed as displacements per atom, is considerably higher in the natural samples, and the atomic-scale process leading to metamictization appears to develop differently. Ion-beam-induced amorphization data were used to calculate the {alpha}-decay-event dose required for amorphization in terms of a critical radionuclide concentration, i.e., the concentration above which a sample of a given age will become metamict at a specific temperature. This equation was applied to estimate the reliability of U-Pb ages, to provide a qualitative estimate of the thermal history of high-U natural zircons, and to predict whether actinide-bearing zircon or monazite nuclear waste forms will become amorphous (metamict) over long timescales.

  11. Synthesis and characterization of new crystalline titanates

    E-print Network

    Gonzalez, Edwin Sabath

    1991-01-01

    of the Type 2 crystalline titanate 12. Comparison between the X-Ray diffraction patterns of a sample calcined in nitrogen and a sample as prepared of the Type 2 crystalline titanate. 13. Comparison between the X-Ray diffraction patterns of a sample... calcined in air and a sample as prepared of the Type 2 crystalline titanate Figure Page 14. Electron micrographs of Type 2 crystalline titanate, batch ? 35 70 15. Electron micrographs of Type 2 crystalline titanate, batch ? 47 71 16. Electron...

  12. Highly reliable 50nm-thick PZT capacitor and low voltage FRAM device using Ir\\/SrRuO3\\/MOCVD PZT capacitor technology

    Microsoft Academic Search

    D. C. Yoo; B. J. Bae; J.-E. Lim; D. H. Im; S. O. Park; S. H. Kim; U. I. Chung; J. T. Moon; B. I. Ryu

    2005-01-01

    For the first time, we successfully developed highly reliable 50nm-thick polycrystalline PZT capacitor using noble Ir\\/SrRuO3 top electrode and MOCVD PZT technology. In the 50nm-thick PZT capacitor, 33?C\\/cm2 of remanent polarization and 0.7V of saturation voltage have been demonstrated. Moreover, after 100hrs of bake-time at 150°C, opposite-state polarization margin was over 23?C\\/cm2, which is world-wide best result so far achieved.

  13. Will Titan lose its veil?

    NASA Astrophysics Data System (ADS)

    Dimitrov, V.

    2007-08-01

    Methane CH4 is the only highly reactive and short-lived background component in Titan's atmosphere, so its overall reserve predetermines both features and duration of atmospheric chemical activity. Titan's global chemical activity is considered in terms of methane cycle. One cycle is defined as a period T0=7.0.1014s of complete photochemical destruction of methane's observable atmospheric content CH04 = 2.33.1017 kg. Cycle duration T0, number of the past NP =200±20, future NF =500±50 and total Nmax=NP+NF =700±70 cycles are the main quantitative indices of the global chemical activity [2]. The fact that the period T0 is much less than Titan's lifetime TT =1.42*1017s implies that the current content CH04 is continuously replenishing by methane global circulation. There are two sources of this replenishment, i.e. the outgassing of primordial methane reserve trapped in Titan's interior as the clathrate, and the (sub)ground liquidphase reduction of non-saturated final products of the atmospheric photochemical process. Internal reserve provides the dominant portion (>95%) of general recycling, while reducing reconversion is the minor constituent of the global balance. Yet, there is the problem of the availability of the off-the-shelf trapped methane. Overall admissible stock of the trapped methane depends on its internal allocation and falls in the range (CH4)max1,2=(15.3÷33.3).1020 kg, while continuous atmospheric activity during the whole Titan's life TSun 5.0.1017s needs only (CH4)crit=(CH04 ).Nmax = .(CH4)max 1.65.1020 kg. In turn, this bulk (CH4)crit depends on the clathrate cage-filling efficiency (molecular packing index) {kg CH4/kg clathrate} and can be provided if equals respectively to [1] crit1= (TSun/T0).[(CH4)0/[(CH4)max1] = 5.45.10-3 crit2= (TSun/T0).[(CH4)0/[(CH4)max2] = 2.51.10-3 Thus, the interrelation of overall trapped stock (CH4)max and crucial -values assigns the critical value (CH4)crit that in turn predetermines the very fate of Titan's veil. If the real stock (CH4)real (CH4)crit=1.65.1020 kg, than Titan will lose its veil inevitably (scenario of the "mosaic history"), otherwise (CH4)real (CH4)crit the veil survives down to Titan's dying day ("continuous history"). References [1] H. B. Niemann and 17-co-authors, Nature, 438, 779, (2005). [2] V. Dimitrov, Prog. React. Kin. Mech. 30, N4, 227, (2006).

  14. Assessment of the suitability of zircons for thermoluminescence dating

    E-print Network

    Donoghue, Joseph

    Assessment of the suitability of zircons for thermoluminescence dating H.J. van Esa, *, H.W. den 1 March 2000; accepted 10 March 2000 Abstract A suit of zircon (ZrSiO4) samples has been selected, and that zircons are HREE enriched. In all sediment samples used in this work, we found signi®cant concentration

  15. Evolution of zircon microstructures: nanoscale processes and regional controls

    E-print Network

    Glasgow, University of

    Evolution of zircon microstructures: nanoscale processes and regional controls Martin Lee* & Tim characteristics of zircon microstructures and the thermal controls on their development. Previous work of zircon with amorphous domains produced by radiation damage have the potential to encode a rich record

  16. Multiple Soft-Mode Vibrations of Lead Zirconate J. Hlinka,*

    E-print Network

    Ku?el, Petr

    Multiple Soft-Mode Vibrations of Lead Zirconate J. Hlinka,* T. Ostapchuk, E. Buixaderas, C. Kadlec lead zirconate single crystals have yielded a comprehensive picture of temperature (AFE) oxide. Most recent stud- ies suggest that the AFE state in lead zirconate is induced by a single

  17. Vapor deposited samarium zirconate thermal barrier coatings Hengbei Zhao a,

    E-print Network

    Wadley, Haydn

    Vapor deposited samarium zirconate thermal barrier coatings Hengbei Zhao a, , Carlos G. Levi b form 24 March 2009 Available online 1 April 2009 Keywords: Samarium zirconate Directed-vapor deposition Thermal barrier coatings The rare earth zirconates (M2Zr2O7, M=LaGd) have a low intrinsic thermal

  18. Detrital zircon geochronologyof Carboniferous^ Cretaceousstratainthe Lhasaterrane,SouthernTibet

    E-print Network

    Detrital zircon geochronologyof Carboniferous^ Cretaceousstratainthe Lhasaterrane Palaeozoic and Mesozoic sedimentary rocks in the Lhasa terrane for detrital zircon uranium^lead (U^Pb) analysis. The 4700 detrital zircon U^Pb ages reported in this paper provide the ¢rst signi¢cant detrital

  19. Experimental calibration of oxygen isotope fractionation between quartz and zircon

    E-print Network

    Bindeman, Ilya N.

    Experimental calibration of oxygen isotope fractionation between quartz and zircon Dustin Trail a the results of an experimental calibration of oxygen isotope fractionation between quartz and zircon. Data between quartz and zircon can be described by: 1000 ln aqtz­zrc ¼ ð2:33 Æ 0:24Þ Â 106 =T2 ðin KÞ

  20. John I. Garver Discussion: ``Metamictisation of natural zircon: accumulation versus

    E-print Network

    Garver, John I.

    John I. Garver Discussion: ``Metamictisation of natural zircon: accumulation versus thermal radiation damage, age, and radionuclide content of natural zircons using confocal laser-Raman spectroscopy (Nasdala et al. 2001). They investigated a series of naturally damaged zircons and demonstrated that Raman

  1. OPTICAL AND DOSIMETRIC PROPERTIES OF ZIRCON N. Kristianpoller

    E-print Network

    Chen, Reuven

    OPTICAL AND DOSIMETRIC PROPERTIES OF ZIRCON N. Kristianpollerà , D. Weiss and R. Chen School-Aviv 69978, Israel Irradiation effects were investigated in zircon crystals by methods of optical absorption. The radiation sensitivity of zircon was by an order of magnitude lower than that of TLD-100. The 355 K TL peak

  2. Supplementary Figures 1, 2, 3 Morphology of the zircons

    E-print Network

    Rudnick, Roberta L.

    Supplementary Figures 1, 2, 3 Morphology of the zircons Cathodoluminescence (CL) images of the selected zircons analyzed by SHRIMP II are shown in Supplementary Figures 1, 2, 3. Circles indicate from the lower unit of the Xinglonggou lavas are dominated by euhedral needle shaped zircons

  3. Preparation of Lead Zirconate by Homogeneous Precipitation and Calcination

    E-print Network

    Tas, A. Cuneyt

    Preparation of Lead Zirconate by Homogeneous Precipitation and Calcination Ersin Emre Oren, Ercan. Introduction LEAD ZIRCONATE (PbZrO3) is an antiferroelectric ceramic with a Curie temperature of 230°C Piezoelectric and dielectric prop- erties of lead zirconate thin films, derived from a sol­gel tech- nique, were

  4. Zircon Th/U ratios in magmatic environs

    NASA Astrophysics Data System (ADS)

    Kirkland, C. L.; Smithies, R. H.; Taylor, R. J. M.; Evans, N.; McDonald, B.

    2015-01-01

    A comprehensive database of zircon composition in West Australian magmatic rocks reveals negative correlations between both U and Th zircon/whole rock ratio and the zircon saturation temperature, with the observed change with temperature less for U(zircon/whole rock) than for Th(zircon/whole rock). This observation implies a systematic increase in the zircon/rock ratio with falling crystallisation temperature, a result which replicates findings from experimental partition coefficient studies. Under equilibrium conditions there is a trend to lower zircon Th/U with increasing melt temperature which can be attributed to lattice strain. However, within a fractionating magma, Ti-in-zircon temperatures yield the opposite relationship of lower zircon Th/U in cooler melts. This is due to zircon growth under non-equilibrium conditions with greater incompatibility of Th relative to U, and the removal and segregation of mineral precipitates. These observations can be used as a tool to determine whether zircon growth was in a liquid of similar composition to the observed whole rock. We present an equation that estimates the degree of fractionation between the whole rock composition and the zircon parental liquid. This parameter demonstrates the dissimilarity between the liquid from which the zircon grew and the whole rock composition and aids in distinguishing mesostasis growth in fractionated melt versus cumulate growth in less fractionated magma. We use this ratio to investigate zircon growth in igneous rocks of the Musgrave Province. For a suite of c. 1200 Ma magmas that become progressively more fractionated, based on whole rock La/Sm, the fractionation index demonstrates increasing compositional differences between the whole rock and the zircon growth liquid. In the most extreme case independent petrographic evidence indicates mesostasis growth of zircon, whereas in the least fractionated melt zircon growth is established to be close to equilibrium with a zircon saturation temperature of c. 900 °C likely being accurate. In contrast, zircon crystals from a rhyolite of the c. 1070 Ma Giles Supervolcano have distinctive compositional discordances indicative of antecrystic components. The fractionation factor in this rock implies some zircon growth under higher temperature conditions than the whole rock zircon saturation temperature.

  5. Cratering on Titan and implications for Titan's atmospheric history

    Microsoft Academic Search

    Steffi Engel; Jonathan I. Lunine; William K. Hartmann

    1995-01-01

    A means for putting limits on the history of Titan's atmosphere is proposed by considering the breakup of bolides during atmospheric entry and the resulting modification of the crater size-frequency distribution at the surface, which will be determined by radar during the Cassini-Huygens mission. Bolides entering the atmosphere experience forces that eventually exceed the body's strength and disruption occurs. The

  6. Titan-izing the Target Module V.B. Graves

    E-print Network

    McDonald, Kirk

    NATIONAL LABORATORY U. S. DEPARTMENT OF ENERGY Hg Target Module Issues 16 Dec 2005 Jet Deflector Should of deflector Issue/CommentAction #12;OAK RIDGE NATIONAL LABORATORY U. S. DEPARTMENT OF ENERGY Hg Target Module to be custom machined · Jet deflector fabrication simpler if the primary containment is titanium · Titan

  7. Fission track dating of kimberlitic zircons

    USGS Publications Warehouse

    Haggerty, S.E.; Raber, E.; Naeser, C.W.

    1983-01-01

    The only reliable method for dating kimberlites at present is the lengthy and specialized hydrothermal procedure that extracts 206Pb and 238U from low-uranium zircons. This paper describes a second successful method by fission track dating of large single-crystal zircons, 1.0-1.5 cm in dimension. The use of large crystals overcomes the limitations imposed in conventional fission track analysis which utilizes crushed fragments. Low track densities, optical track dispersion, and the random orientation of polished surfaces in the etch and irradiation cycle are effectively overcome. Fission track ages of zircons from five African kimberlites are reported, from the Kimberley Pool (90.3 ?? 6.5 m.y.), Orapa (87.4 ?? 5.7 and 92.4 ?? 6.1 m.y.), Nzega (51.1 ?? 3.8 m.y.), Koffiefontein (90.0 ?? 8.2 m.y.), and Val do Queve (133.4 ?? 11.5 m.y.). In addition we report the first radiometric ages (707.9 ?? 59.6 and 705.5 ?? 61.0 m.y.) of crustal zircons from kimberlites in northwest Liberia. The fission track ages agree well with earlier age estimates. Most of the zircons examined in this study are zoned with respect to uranium but linear correlations are established (by regression analysis) between zones of variable uranium content, and within zones of constant uranium content (by analysis of variance). Concordance between the fission track method and the U/Pb technique is established and we concluded that track fading from thermal annealing has not taken place. Kimberlitic zircons dated in this study, therefore, record the time of eruption. ?? 1983.

  8. Origin of Zircon in Ophiolitic Mantle Rocks

    NASA Astrophysics Data System (ADS)

    Robinson, P. T.; Yang, J.; Schmitt, A. K.; Li, J.; Ma, C.

    2011-12-01

    Zircon xenocrysts in ultramafic rocks are typically interpreted as grains picked up by intrusion of mantle rocks into crustal sequences and are taken as evidence of underlying continental crust. However, ultramafic rocks of the Luobusa and Dongqiao ophiolites of Tibet and the Semail ophiolite of Oman contain rounded zircon grains that are much older than the ophiolites themselves. In the Tibetan ophiolites the zircon is accompanied by diamonds, moissanite, corundum, coesite, kyanite, garnet and rutile and numerous highly reduced phases, including PGE and base-metal alloys and native elements. The zircon grains range from 20 to 300 ?m across, and are mostly well rounded with very complex internal structures. A few grains are euhedral to subhedral and have concentric zoning suggesting an igneous origin. Many of the grains contain low-pressure inclusions of quartz, rutile, orthoclase, mica, ilmenite and apatite. 206Pb/238U SIMS dates for the Luobusa zircons range from 549±19 to 1657±58 Ma, whereas those for the Dongqiao ophiolites range from 484±49 to 2515±276 Ma. These ages are much older than the host ophiolites (~126 Ma and 147 Ma, respectively). Sixteen dates on zircons from the Semail ophiolite range in age from 84±4 to 1386±48 Ma. Four of these grains are euhedral to subhedral and have late Cretaceous ages essentially the same as the host ophiolite (92±4 to 99±5 Ma), but most are much older. The one younger age of 84 Ma probably reflects slight Pb loss. Many grains in all three ophiolites have distinct cores surrounded by much younger rims, which are still older than the host ophiolites. All of the studied zircons have REE and trace element compositions characteristic of continental crustal grains. Because ophiolites are tectonically emplaced slices of oceanic lithosphere, the possibility of crustal contamination during formation is highly unlikely. Thus, the old zircons in these ophiolites are interpreted as crustal xenocrysts, introduced into the mantle by earlier subduction of continental crust in orogenic belts.

  9. Effect of the Porosity of PZT Thick Films on Mass Sensitivity and Resonance Force for Cantilever Type Bio Sensors

    Microsoft Academic Search

    Jae Hong Park; Tae Yun Kwon; Dae Sung Yoon; Tae Song Kim; Hwan Kim

    2006-01-01

    PZT thick films fabricated through the screen printing show a porosity ranging from 20% to 40%. Unfortunately, these high porosities of thick films greatly affect electromechanical characteristics of PZT thick film cantilevers. In this paper, we report a systematic analysis regarding the effect of the thick film porosity on the electromechanical characteristics of the PZT thick film cantilever. PZT (Pb(Zr0.52Ti0.48)O3)

  10. Properties of PZT Nano-Powder Doped Silica Films Prepared by Sol-Gel Process

    Microsoft Academic Search

    Pei-Chen Yen; Jiann-Shiun Kao; Shang-Yu Huang; Chuen-Horng Tsai; I-Nan Lin

    2002-01-01

    Silica films doped with amorphous PZT nanopowder were prepared by a modified TEOS sol-gel process. The films were annealed by conventional furnace or rapid thermal annealing methods at 700 ¯ respectively, and were examined by field emission scanning electron microscopy and spectro-ellipsometer. Most of the PZT particles were detached from the film after annealing. To avoid this phenomenon, a hydrothermal

  11. Dome Shaped Touch Sensor Using PZT Thin Film made by Hydrothermal Method

    Microsoft Academic Search

    Fumihito Arai; Toshio Fukuda; Kouichi Itoigawa; Yasunori Thukahara

    2001-01-01

    We propose a dome shaped touch sensor unit, which is small and is applicable in high temperature environment. The PZT thin film was made on the half- round Ti substrate, and the electrodes were deposited on its surface to form the sensor and driving actuator. The PZT thin film was made on the curved surface of the substrate by the

  12. PRESSURE CONTROL CHARACTERISTICS OF ELECTRO-PNEUMATIC REGULATOR WITH TWO MULTILAYERED PZT VALVES

    Microsoft Academic Search

    So-Nam Yun; Young-Bog Ham; Jung-Ho Park; Deok-Yong Ham; Il-Young Lee

    2008-01-01

    This paper presents pressure control method using the electro-pneumatic regulator with two multilayered PZT valves. An electro-pneumatic regulator is a type of pressure control valve that is a combination of a poppet valve for main pressure control, two multilayered PZT valves for pilot pressure control, a microprocessor with a feedback controller and a pressure sensor. The benefits of bender type

  13. Improving the dielectric and piezoelectric properties of screen-printed Low temperature PZT/polymer composite

    E-print Network

    in energy harvesting, sensing and actuating applications. Piezoelectric materials can be used in energyImproving the dielectric and piezoelectric properties of screen-printed Low temperature PZT. This paper reports an improvement in dielectric and piezoelectric properties of screen-printed PZT

  14. Damage Detection for Composite Laminate Plates with A Distributed Hybrid PZT\\/FBG Sensor Network

    Microsoft Academic Search

    Zhanjun Wu; Xinlin P. Qing; Fu-Kuo Chang

    2009-01-01

    Debond detection is a critical technique to ensure composite structural safety. Although there are many novel sensors being developed in recent years, piezoelectric transducers (PZT) and fiber Bragg grating (FBG) sensors have been shown as ideal sensors for monitoring structural health. To utilize their merits and overcome their drawbacks a hybrid PZT\\/FBG system has been developed to detect damage in

  15. Micro-motion exposure method based on PZT piezoelectric ceramics

    NASA Astrophysics Data System (ADS)

    Sun, Wenjun; Zhang, Mei-heng; Meng, Zhong

    2009-07-01

    There mainly is laser digital photofinishing technique and digital photofinishing technique based on LCD consisting of TFT and LCOS in the digital photofinishing field at the present time. The former have a good many merit such as wide color gamut, high processing rate, large output size and high brightness, but his cost is very high, his maintain technique being comparatively complex, that result in difficult use for people. The utilization ratio of the latter is low because of lower resolution and lower aperture ratio for LCD, but the digital photofinishing based on LCD have lower cost and higher utilization ration, being suitable for people's current standard of living. Considering above mentioned problem, a micro-motion exposure method based on PZT piezoelectric ceramics used in digital image photofinishing is presented. The two-dimension micro-motion exposure system consisting of PZT piezoelectric ceramics, LCD panel, polarizing film and spring strip is designed. By means of PZT piezoelectric ceramics the LCD panel is removed about the one half of the pixel size of the LCD panel for four times from the original place, at the same time imaging system is exposed four times at the printing paper. The software is used to control the time synchronization, the exposure time and motion range of the LCD panel. The system has advantages such as shorter response time than 0.1seconds, lesser motion error than 0.01 microns, high stability and repeatability. Experimental results show that the proposed micro-motion exposure method improve the picture brightness and enlarge output size, at the meantime reducing the cost of the system.

  16. The effect of biaxial texture on the effective electromechanical constants of polycrystalline barium titanate and lead titanate thin films

    E-print Network

    Atwater, Harry

    barium titanate and lead titanate thin films Jennifer L. Ruglovsky a,*, Jiangyu Li b , Kaushik to an enhanced piezoelectric effect for barium titanate films, but not for lead titanate. Twist texturing about for a polycrystalline film. We explore tetragonal 4MM materials, and give specific results for barium titanate and lead

  17. Cathodoluminescence of radiation-induced zircon

    NASA Astrophysics Data System (ADS)

    Tsuchiya, Y.; Nishido, H.; Kayama, M.; Noumi, Y.

    2013-12-01

    Zircon occurs as a common accessory mineral in igneous, metamorphic and sedimentary rocks, and maintains much information on thermal history, metamorphic process and natural radiation dose accumulated in the mineral. U-Pb zircon dating (e.g., SHRIMP) is an important tool to interpret a history of the minerals at a micrometer-scale, where cathodoluminescence (CL) image has been used for identification of internal zones and domains having different chemical compositions and/or structures with a high spatial resolution. The CL of zircon is derived from various types of emission centers, which are derived from impurities such as rare earth elements (REE) and structural defects. In fact, the CL features of zircon are closely related to metamorphic process and radiation from contained radionuclides as well as geochemical condition of its formation. Most zircon has yellow emission, which seems to be assigned to UO2 centers or radiation-induced defect during metamictization of the lattice by alpha particles from the decay of U and Th. In this study, the radiation effects on zircon CL have been studied for He+ ion-implanted samples annealed at various temperatures to clarify radiation-induced defect centers involved with the yellow CL emission in zircon. Single crystals of zircon from Malawi (MZ), Takidani granodiorite (TZ) and Kurobegawa granite (KZ) were selected for He+ ion implantation experiments. The polished plates of the samples were implanted by He+ ion 4.0 MeV corresponding to energy of alpha particle from 238 U and 232Th. CL spectra in the range from 300 to 800 nm with 1 nm step were measured by a scanning electron microscopy-cathodoluminescence (SEM-CL). CL spectra of untreated and annealed zircon show emission bands at ~370 nm assigned to intrinsic defect centers and at ~480, ~580 and ~760 nm to trivalent Dy impurity centers (Cesbron et al., 1995; Gaft et al, 2005). CL emissions in the yellow-region were observed in untreated zircon. The TZ and KZ indicate youngest formation ages of 1.93-1.20 Ma and 1.7-0.9 Ma, respectively (Harayama,1994; Harayama et al., 2010) in the world. In this case, it is hardly to detect yellow CL emissions derived from radiation-induced defect center, suggesting low radiation dose of alpha radiation from 238U and 232Th on them. CL spectra of MZ, TZ and KZ showed an increase in the intensities of yellow emissions with an increase in radiation dose of He+ ion implantation, though He+ ion implantation reduces the intensities of their impurity centers. CL intensity in the yellow region depends on radiation dose of He+ ion implantation. Therefore, if the component of yellow emission could be deconvoluted from the CL spectra in zircon, its intensity will be used for an indicator to evaluate total exposure doses on it during geological age.

  18. Crystallization of amorphous bismuth titanate

    Microsoft Academic Search

    Seiji Kojima; Anwar Hushur; Fuming Jiang; Sinichi Hamazaki; Masaaki Takashige; Min-Su Jang; Shiro Shimada

    2001-01-01

    We studied the transformation of amorphous bismuth titanate by heat treatments. After an as-quenched amorphous sample was annealed at 500 °C, the lowest Raman peak became intense like a boson peak for glass. This fact indicates the formation of intermediate range order. The medium range correlation length of 7 nm calculated from the boson peak frequency is in agreement with

  19. Campus Contacts Titan Bookstore Cafe

    E-print Network

    de Lijser, Peter

    Campus Contacts Library Titan Bookstore Cafe Student A airs Susan M. Cooper Dean (657) 278 drawings) Pizza with the Dean April 18th , 5:30 p.m. - 6:30 p.m. IRVC-Lobby Stress Management Workshop with Student Affairs and Admissions, Registration, and Cashiering. Lunch with the Dean was followed

  20. Organic chemistry in Titan's atmosphere

    NASA Technical Reports Server (NTRS)

    Scattergood, T.

    1982-01-01

    Laboratory photochemical simulations and other types of chemical simulations are discussed. The chemistry of methane, which is the major known constituent of Titan's atmosphere was examined with stress on what can be learned from photochemistry and particle irradiation. The composition of dust that comprises the haze layer was determined. Isotope fractionation in planetary atmospheres is also discussed.

  1. Photochemical Modeling of Titan's Atmosphere

    Microsoft Academic Search

    D. Toublanc; J. P. Parisot; J. Brillet; D. Gautier; F. Raulin; C. P. McKay

    1995-01-01

    We have developed a new photochemical model of Titan's atmosphere which includes all the important compounds and reactions in spherical geometry from the surface to 1240 km. Compared to the previous model of Yung et al. (1984, Astrophys. J. Suppl. 55, 465-506), the most significant recent change in the reactions used is the updated methane photodissociation scheme (Mordaunt et al.

  2. The Induced Magnetosphere of Titan

    NASA Astrophysics Data System (ADS)

    Russell, Christopher T.; Neubauer, F. M.; Dougherty, M. K.; Bertucci, C.; Arridge, C. S.

    2006-09-01

    C. T. Russell1, F. M. Neubauer2, M. K. Dougherty3, C. Bertucci3, and C. S. Arridge3 1IGPP and ESS, University of California, Los Angeles, CA, USA 2IGM, Universitaet zu Koeln, Germany 3Blackett Laboratory, Imperial College, London, U.K. The large variety of Titan passes by Cassini has enabled a new portrait of its interaction with the Saturnian magnetosphere to be drawn. The Saturnian magnetosphere is stretched by the corotating plasma and bent upward around its edges, much like a bowl. At the present time Titan orbits beneath this bowl so that the ambient magnetic field at Titan's orbit is almost continually inward toward Saturn, slightly southward and pointed in the direction of Saturn's rotation. Superimposed on this is a broad region of weak draping that corresponds to a magnetosonic-fast-mode wave creating a compressional disturbance extending far upstream. Downstream from Titan is a slow-mode/Alfven-mode wake of enhanced and strongly bent magnetic field that corresponds to the classical Alfven wing seen at Io in the jovian system extending far from the satellite with the amplitude fading away slowly with increasing distance. This wake is strong enough to cause a flow-aligned reversal in the direction of the magnetic field.

  3. Effect of substrate bending on the piezoelectric measurement of PZT thin film

    NASA Astrophysics Data System (ADS)

    Xu, Xiaohui; Tang, Jianhong; He, Liangna

    2009-05-01

    Bonding conditions between PZT thin film and sample holder greatly affect the strain measurement of the PZT sample. The influence of various bonding conditions on the measured displacement were analyzed using finite element analysis (FEA). One-end fixed sample induces the maximum bending displacement. Experiments were performed on sol-gel derived PZT thin film. The voltage-displacement curve and "butterfly" loop were measured using laser Doppler method with phase detection. Experimental results agreed well with the simulated ones. The measured frequency dependence of piezoelectric response of PZT thin film indicated that, if the operating frequency was lower than 2 kHz, good bonding effect could be obtained when the entire back surface of the sample was glued to a rigid supporter using epoxy resin. A simple bonding model which considered the adhesives as a spring was used to estimate the frequency response of PZT thin film sample.

  4. Observed Seasonal Change in Titan's Thermosphere

    NASA Astrophysics Data System (ADS)

    Westlake, Joseph H.; Waite, H.; Bell, J. M.; Perryman, R.

    2013-10-01

    Titan’s upper thermosphere has exhibited structural changes throughout the Cassini mission to date. Some thermospheric structure has been tied to magnetospheric forcing (Westlake et al. 2011) and wave activity (Snowden et al. 2013). Now, after several years of observation we have evidence of clear solar forcing of Titan’s thermosphere. During the time between TA (2004) and T86 (2012) N2 and CH4 have declined in density resulting in a factor of 3 reduction of N2 and a factor of 5.6 reduction in CH4 at 1000 km. This decline is in response to the solar conditions at Titan, either through a change in distance from the Sun (Titan has receded nearly 1AU from the Sun since 2004), a change in the solar activity level, or a change in the sub-solar point (season). In the most recent flybys Titan’s methane has declined at an enhanced rate. We postulate that this decline is a direct response to the solar maximum conditions in 2012. Titan’s N2 responds primarily to changes in the thermal structure over a timescale of months to years, while CH4 responds to changes in solar forcing on shorter timescales (Bell et al. 2011). We illustrate this process though analysis of the INMS data since TA and modeling studies using the T-GITM global circulation model.

  5. Plutonium Stabilization in Zircon: Effects of Self-Radiation

    SciTech Connect

    Weber, William J.; Hess, Nancy J.; Williford, Ralph E.; Heinisch, Howard L.; Begg, Bruce D.; Conradson, Steven D.; Ewing, Rodney C.

    2000-07-10

    Zircon is the most thoroughly studied of all candidate ceramic phases for the stabilization of plutonium. Self-radiation damage from alpha-decay of the Pu can significantly affect the structure and properties of zircon. Two types of synthetic Pu-containing zircons, prepared in 1981, have provided an opportunity to characterize in detail the effects of Pu decay on the structure and properties of zircon and to make unique comparisons to observations of radiation effects in natural zircons. One set of zircon samples contained Pu-238; while the other set of samples contained Pu-239. In both instances, the Pu was substituted directly for Zr. The zircons containing Pu-238, with its 87.7 year half-life, provided a means of accelerating the alpha-decay rate by a factor of 250 when compared to the zircons containing Pu-239. Self-radiation from Pu decay in zircon results in the simultaneous accumulation of point defects and amorphous domains that eventually lead to a completely amorphous state. The swelling in zircon increases sigmoidally with dose and is well saturated at the highest dose. In all cases, the swelling can be accur-ately modeled based on the contributions from crystalline and amorphous components. Detailed X-ray absorption spectroscopy and X-ray diffraction methods have characterized the short-range and long-range structures of each zircon type. The amorphous state of zircon is consistent with the loss of long-range order and edge-sharing relationships between silica and zirconia polyhedra. Despite this, a distorted zircon structure and stoichiometry, which consists of silica and zirconia polyhedra that have rotated relative to each other, is retained over length scales up to 0.5 nm. Atomic-scale computer simulations have also been used to study defect accumulation and amorphization in zircon. The simulation results for the amorphous fraction as a function of alpha-decay dose are in excellent agreement with the experimental results.

  6. Micromechanical modelling of remanent properties of morphotropic PZT

    NASA Astrophysics Data System (ADS)

    Neumeister, Peter; Balke, Herbert

    2011-09-01

    The present paper investigates the capability of micromechanical material models to predict the ferroelectric behaviour of morphotropic PZT ceramics in a rate-independent approximation based on realistic microscopic material parameters. Starting point is a three-dimensional tetragonal model, which builds on the model of Pathak and McMeeking [2008. Three-dimensional finite element simulations of ferroelectric polycrystals under electrical and mechanical loading. Journal of the Mechanics and Physics of Solids 56, 663-683]. Volume fractions of the crystallographic variants represent the domain structure inside the grains. Interactions between the grains are taken into account by means of a representative volume element of the grain compound. A simplified set of realistic microscopic material parameters of the lattice in terms of Young's modulus, Poisson's ratio, dielectric constant, and spontaneous strain and polarisation is derived from experimental data and theoretical results given in the literature. The simulation of the macroscopic remanent polarisation and strain response due to two load cases shows explicitly that the tetragonal model is not capable to reproduce the behaviour of morphotropic PZT. Therefore, the model is extended by the rhombohedral phase, allowing a mixture of both phases with varying quantities inside the grains. A comparison of our results with experimental data shows a remarkably good agreement, revealing the capability of the extended model.

  7. Crack detection of railway turnouts using PZT sensors (presentation video)

    NASA Astrophysics Data System (ADS)

    Ni, Yiqing; Li, Z. G.; Wu, F.

    2014-05-01

    Railway turnouts (railroad switches) are the weakest components of a rail track system. Cracks may occur in the railway turnouts due to cyclic loadings and impact loadings imposed by passing trains. It is of great significance to continuously monitor the health condition of the railway turnouts and promptly detect crack once it initiates. It is well-known that acoustic emission (AE) signals are generated when a crack initiates and propagates. Detecting the high-frequency AE signals by piezoelectric sensors can help identify the crack and its location. This paper reports the design and implementation of a PZT-based system for crack monitoring of railway turnouts. This online monitoring system is activated for signal collection by a trigger system when a train is arriving to pass through the instrumented railway turnout. It mainly detects the AE signals generated when a crack initiates during the train passage or when the initiated crack expands during the passage of a heavy haul wagon. This system has been installed on a railroad line for over one year and has successfully detected the damage occurring at a railroad switch during its service period. This paper also briefs a guided-wave-based system for monitoring of micro-cracks in rail tracks by integrating FBG and PZT sensors.

  8. Hubble Observes Surface of Titan

    NASA Technical Reports Server (NTRS)

    1994-01-01

    Scientists for the first time have made images of the surface of Saturn's giant, haze-shrouded moon, Titan. They mapped light and dark features over the surface of the satellite during nearly a complete 16-day rotation. One prominent bright area they discovered is a surface feature 2,500 miles across, about the size of the continent of Australia.

    Titan, larger than Mercury and slightly smaller than Mars, is the only body in the solar system, other than Earth, that may have oceans and rainfall on its surface, albeit oceans and rain of ethane-methane rather than water. Scientists suspect that Titan's present environment -- although colder than minus 289 degrees Fahrenheit, so cold that water ice would be as hard as granite -- might be similar to that on Earth billions of years ago, before life began pumping oxygen into the atmosphere.

    Peter H. Smith of the University of Arizona Lunar and Planetary Laboratory and his team took the images with the Hubble Space Telescope during 14 observing runs between Oct. 4 - 18. Smith announced the team's first results last week at the 26th annual meeting of the American Astronomical Society Division for Planetary Sciences in Bethesda, Md. Co-investigators on the team are Mark Lemmon, a doctoral candidate with the UA Lunar and Planetary Laboratory; John Caldwell of York University, Canada; Larry Sromovsky of the University of Wisconsin; and Michael Allison of the Goddard Institute for Space Studies, New York City.

    Titan's atmosphere, about four times as dense as Earth's atmosphere, is primarily nitrogen laced with such poisonous substances as methane and ethane. This thick, orange, hydrocarbon haze was impenetrable to cameras aboard the Pioneer and Voyager spacecraft that flew by the Saturn system in the late 1970s and early 1980s. The haze is formed as methane in the atmosphere is destroyed by sunlight. The hydrocarbons produced by this methane destruction form a smog similar to that found over large cities, but is much thicker.

    Smith's group used the Hubble Space Telescope's WideField/Planetary Camera 2 at near-infrared wavelengths (between .85 and 1.05 microns). Titan's haze is transparent enough in this wavelength range to allow mapping of surface features according to their reflectivity. Only Titan's polar regions could not be mapped this way, due to the telescope's viewing angle of the poles and the thick haze near the edge of the disk. Their image-resolution (that is, the smallest distance seen in detail) with the WFPC2 at the near-infrared wavelength is 360 miles. The 14 images processed and compiled into the Titan surface map were as 'noise' free, or as free of signal interference, as the space telescope allows, Smith said.

    Titan makes one complete orbit around Saturn in 16 days, roughly the duration of the imaging project. Scientists have suspected that Titan's rotation also takes 16 days, so that the same hemisphere of Titan always faces Saturn, just as the same hemisphere of the Earth's moon always faces the Earth. Recent observations by Lemmon and colleagues at the University of Arizona confirm this true.

    It's too soon to conclude much about what the dark and bright areas in the Hubble Space Telescope images are -- continents, oceans, impact craters or other features, Smith said. Scientists have long suspected that Titan's surface was covered with a global ehtane-methane ocean. The new images show that there is at least some solid surface.

    Smith's team made a total 50 images of Titan last month in their program, a project to search for small scale features in Titan's lower atmosphere and surface. They have yet to analyze images for information about Titan's clouds and winds. That analysis could help explain if the bright areas are major impact craters in the frozen water ice-and-rock or higher-altitude features.

    The images are important information for the Cassini mission, which is to launch a robotic spacecraft on a 7-year journey to Saturn in October 1997. About three weeks before Cassini's first flyby

  9. Proton conducting alkaline earth zirconates and titanates for high drain electrochemical applications

    Microsoft Academic Search

    K. D. Kreuer; St. Adams; W. Münch; A. Fuchs; U. Klock; J. Maier

    2001-01-01

    The mobility and stability of protonic defects in acceptor-doped perovskite-type oxides (ABO3) in the system SrTiO3–SrZrO3–BaZrO3–BaTiO3 have been examined experimentally and by computational simulations. These materials have the potential to combine high proton conductivity and thermodynamic stability. While any structural and chemical perturbation originating from the B-site occupation (poor chemical matching of the acceptor-dopant or Zr\\/Ti-mixing) leads to a significant

  10. Photovoltaic Effect of Crystalline-Oriented Lead Lanthanum Zirconate Titanate in Layered Film Structure

    NASA Astrophysics Data System (ADS)

    Ichiki, Masaaki; Furue, Harumi; Kobayashi, Takeshi; Morikawa, Yasushi; Nonaka, Kazuhiro; Nakada, Takeshi; Wang, Zhan Jie; Maeda, Ryutaro

    2006-12-01

    Photovoltaic (Pb,La)(Zr,Ti)O3 (PLZT) films in a layered structure of different crystallographic orientations are fabricated by optimized metalorganic deposition (MOD). Such films of (001) orientation exhibit a photovoltaic electrical power approximately 20 times higher than that of random films. The anisotropic optical properties of the oriented films, including dark conductivity, photoconductivity and photovoltaic tensors, are obtained quantitatively. These results show that the photovoltaic output current and power of the oriented films are highly improved to be comparable to those of semiconductors and suitable for application in the optical sensor of micro-electro-mechanical systems (MEMS).

  11. The pyrochlore-to-perovskite transformation in solution-derived lead zirconate titanate thin films

    SciTech Connect

    Voigt, J.A.; Tuttle, B.A.; Headley, T.J.; Lamppa, D.L.

    1995-05-01

    The authors have characterized the pyrochlore-to-perovskite crystallization process in solution-derived Pb(Zr{sub 0.20}Ti{sub 0.80})O{sub 3} thin films on (100) MgO single crystal substrates. It has been determined that the perovskite phase nucleated preferentially at the film/MgO interface out of a nanocrystalline ({approx}100{angstrom} grains) pyrochlore matrix. During the early stages of the pyrochlore-to-perovskite conversion process, perovskite growth proceeded nearly isotropically from the substrate to form hemispherically shaped grains. Deviations from isotropic growth were shown to result from a growth dependence based on the crystallographic orientation of a growing perovskite grain relative to the orientations of pyrochlore grains being transformed. The volume change that occurs during the pyrochlore-to-perovskite transformation along with two-dimensional grain growth has been used to develop a mechanism for formation of porosity that commonly is concentrated in grain boundary regions.

  12. Polar nanodomains and local ferroelectric phenomena in relaxor lead lanthanum zirconate titanate ceramics

    SciTech Connect

    Shvartsman, V.V.; Kholkin, A.L.; Orlova, A.; Kiselev, D.; Bogomolov, A.A.; Sternberg, A. [Department of Ceramics and Glass Engineering and Center for Research in Ceramic and Composite Materials (CICECO), University of Aveiro, 3810-193 Aveiro (Portugal); Department of Physics, Tver State University, 170000 Tver (Russian Federation); Institute of Solid State Physics, University of Latvia, LV-1063 Riga (Latvia)

    2005-05-16

    Transparent Pb{sub 0.9125}La{sub 0.0975}(Zr{sub 0.65}Ti{sub 0.35}){sub 0.976}O{sub 3} ceramics (conventionally abbreviated as PLZT 9.75/65/35) is a typical relaxor characterized by the absence of the ferroelectric order at the macroscopic scale. In this letter, we report on the observation of complex polar structures on the surface of this material via piezoresponse force microscopy (PFM). The irregular polarization patterns are associated with the formation of a glassy state, where random electric fields destroy the long-range ferroelectric order. The measure of the disorder, the correlation length of {approx}50 nm, was directly deduced from the PFM images. Local poling of relaxor ceramics resulted in the formation of a stable micron-size domain that could be continuously switched under varying dc bias (local relaxor-ferroelectric phase transition). Fractal analysis was applied to analyze the origin of local order in PLZT.

  13. Millimeter-wave magnetoelectric effects in bilayers of barium hexaferrite and lead zirconate titanate

    E-print Network

    Srinivasan, Gopalan

    shift f = AE = H in magnetic excitations and comparison with theory. Studies were performed on bilayers to the bilayer plane and parallel to the magnetic easy axis of BaM. A vector network analyzer Agilent-PNA-E8361A

  14. Lead zirconate titanate on base metal foils: An approach for embedded high-K passive components

    SciTech Connect

    Maria, J.-P.; Cheek, K.; Streiffer, S. K.; Kim, S.-H.; Dunn, G.; Kingon, A. I.

    2000-01-26

    An approach for embedding high-K dielectric thin films into polymer packages has been developed. Pb{sub 0.85}La{sub 0.15}(Zr{sub 0.52}Ti{sub 0.48}){sub 0.96}O{sub 3} thin films were prepared by chemical solution deposition on 50 {micro}m thick Ni-coated Cu foils. Sputter deposited Ni top electrodes completed the all base-metal capacitor stack. After high temperature N{sub 2} crystallization anneals, the PLZT composition showed reduction resistance while the base-metal foils remained flexible. Capacitance density and Loss tangent values range between 300 and 400 nF/cm{sup 2} and 0.01 and 0.02 from 1 to 1,000 kHz respectively. These properties represent a 2 to 3 order of magnitude improvement over available embedded capacitor technologies for polymeric packages.

  15. The extrinsic nature of nonlinear behavior observed in lead zirconate titanate ferroelectric ceramic

    E-print Network

    Cao, Wenwu

    . This lossy nature suggests that the nonlinearities in a ferroelectric ceramic are generated by the domain of nonlinearity) all indicate the extrinsic nature of the nonlinear behavior of ferroelectric ceramics behavior of piezoceramic materials is very important because ferroelectric ceramics are now widely used

  16. Nonaqueous solution synthesis process for preparing oxide powders of lead zirconate titanate and related materials

    DOEpatents

    Voigt, James A. (Corrales, NM); Sipola, Diana L. (Albuquerque, NM); Tuttle, Bruce A. (Albuquerque, NM); Anderson, Mark T. (Woodbury, MN)

    1999-01-01

    A process for producing powders of perovskite-type compounds which comprises mixing a metal alkoxide solution with a lead acetate solution to form a homogeneous, clear metal solution, adding an oxalic acid/n-propanol solution to this metal solution to form an easily filterable, free-flowing precursor powder and then calcining this powder. This process provides fine perovskite-phase powders with ferroelectric properties which are particularly useful in a variety of electronic applications.

  17. Nonaqueous solution synthesis process for preparing oxide powders of lead zirconate titanate and related materials

    DOEpatents

    Voigt, J.A.; Sipola, D.L.; Tuttle, B.A.; Anderson, M.T.

    1999-06-01

    A process is disclosed for producing powders of perovskite-type compounds which comprises mixing a metal alkoxide solution with a lead acetate solution to form a homogeneous, clear metal solution, adding an oxalic acid/n-propanol solution to this metal solution to form an easily filterable, free-flowing precursor powder and then calcining this powder. This process provides fine perovskite-phase powders with ferroelectric properties which are particularly useful in a variety of electronic applications. 4 figs.

  18. Magnetoelectric composite materials based on lead zirconate titanate and nickel ferrite

    SciTech Connect

    Lupeiko, T.G.; Lopatin, S.S.; Lisnevskaya, I.V.; Zvyagintsev, B.I. [Rostov State Univ., Rostov-na-Donu (Russian Federation)

    1994-11-01

    Composite materials that consist of a piezoelectric phase and a magnetostrictive ferrite exhibit a magnetoelectric effect. In composites, this effect is a consequence of the collective mechanical interaction of phases, and it manifests itself via electrical polarization or magnetization in magnetic or electric fields. At present, magnetoelectric composites are more promising materials than single-phase magnetoelectrics; most of the latter exhibit magnetoelectric properties at temperatures of liquid helium or nitrogen. For the best single-phase ferromagnet Cr{sub 2}O{sub 3}, the magnetoelectric conversion factor if {Delta}E/{Delta}H = 25 x 10{sup {minus}3} V/A; the largest {Delta}E/{Delta}H ratios that were achieved for magnetoelectric ceramic materials prepared from powders of BaTiO{sub 3} and Ni{sub 0.97}Co{sub 0.03}Mn{sub 0.1}Fe{sub 1.9}O{sub 4} ferrite and for composites of the BaO-TiO{sub 2}-CoO-Fe{sub 2}O{sub 3} system prepared by unidirectional solidification of eutectic melts are 100 x 10{sup {minus}3} and 163 x 10{sup {minus}3} V/A, respectively. In addition to high {Delta}E/{Delta}H values, composites offer material designers the possibility of adjusting their piezoelectric and magnetostrictive components and of varying the ratios of these components over a wide range. This enables the design of magnetoelectric materials with controlled properties. In this paper, the authors report on the electrophysical and magnetoelectric properties of composites based on LZT and modified nickel ferrite and doped with bismuth, lanthanum, and niobium oxides.

  19. Monolithic smart sensor systems based on lead zirconate titanate thin films

    NASA Astrophysics Data System (ADS)

    Schiller, Peter Joseph

    This work describes the development of monolithic smart sensor systems by integration of surface-micromachining and piezoelectric thin film technologies with a conventional CMOS fabrication process. By integrating the components of a typical data acquisition or control system on a common silicon substrate it is possible to improve performance, reduce overall processing and assembly costs, and miniaturize conventional systems. The monolithic fabrication sequence utilizes conventional IC processing techniques and is built around an n-well mixed analog/digital CMOS process with two layers of polysilicon and two levels of metallization. By combining common processing steps, the piezoelectric and surface-micromachining capabilities add only four lithography steps to the eleven-mask CMOS process. Low-voltage PMOS transistors fabricated in this process were characterized by threshold voltages of 0.5 V and transconductance parameters of 57 muA/Vsp2. Low-voltage PMOS transistors fabricated in this process have threshold voltages of -0.7 V and 20 muA/Vsp2 transconductances. A high voltage NMOS transistor was also integrated into the process to buffer low-voltage CMOS signal processing electronics from micromachined electrostatic or piezoelectric actuator loads. High voltage NMOS transistors occupying approximately.0015 cmsp2 sustained a minimum of 100 V drain voltage at 1.2 W. These transistor parameters were not degraded by integration with the monolithic sensors and actuators. The maximum measured unamplified sensitivity of piezoelectric pressure sensors was 245 muV/mubar for a circular device with 200 mum diameter. Analog constant-voltage-gain and general-purpose operational amplifiers were also fabricated in the integrated process. Constant-gain amplifiers based on cascaded operational transconductance amplifiers exhibited a constant gain of 66 dB over a 40 kHz bandwidth. Input capacitance of the amplifier was less than 1 pF while maintaining a maximum input-referred noise level of 4 mu Vsb{p-p}. As an indicator of digital circuit performance, 21-stage buffered CMOS ring oscillators were fabricated and tested, showing an average digital gate delay of 3 nsec. The only performance compromise in CMOS electronics was an increased PMOS drain/source contact resistance due to additional thermal processing required by the microstructures. The minimal degradation of CMOS performance confirms the compatibility of surface-micromachining and piezoelectric thin film technologies with standard IC processing.

  20. Photovoltaic and photostrictive effects in lanthanum-modified lead zirconate titanate ceramics

    Microsoft Academic Search

    Patcharin Poosanaas

    1999-01-01

    Photostriction is the light induced strain in a material, arising from the combination of photovoltaic and converse-piezoelectric effects. The possibility of directly producing strain by light illumination, without any electrical lead wire connection, makes the photostrictive materials very attractive for potential usage in future generation wireless remote controlled micro-actuator and micro-sensor. However, for the fabrication of these devices, materials exhibiting

  1. Cryovolcanic features on Titan's surface as revealed by the Cassini Titan Radar Mapper

    Microsoft Academic Search

    R. M. C. Lopes; K. L. Mitchell; E. R. Stofan; J. I. Lunine; R. Lorenz; F. Paganelli; R. L. Kirk; C. A. Wood; S. D. Wall; L. E. Robshaw; A. D. Fortes; C. D. Neish; J. Radebaugh; E. Reffet; S. J. Ostro; C. Elachi; M. D. Allison; Y. Anderson; R. Boehmer; G. Boubin; P. Callahan; P. Encrenaz; E. Flamini; G. Francescetti; Y. Gim; S. Hensley; M. A. Janssen; W. T. K. Johnson; K. Kelleher; D. O. Muhleman; G. Ori; R. Orosei; G. Picardi; F. Posa; L. E. Roth; R. Seu; S. Shaffer; L. A. Soderblom; B. Stiles; S. Vetrella; R. D. West; L. Wye; H. A. Zebker

    2007-01-01

    The Cassini Titan Radar Mapper obtained Synthetic Aperture Radar images of Titan's surface during four fly-bys during the mission's first year. These images show that Titan's surface is very complex geologically, showing evidence of major planetary geologic processes, including cryovolcanism. This paper discusses the variety of cryovolcanic features identified from SAR images, their possible origin, and their geologic context. The

  2. Wear Behavior of Chromizing-Titanizing Coating

    Microsoft Academic Search

    Lou Baiyang; Xu Bin; Jin Lingchuan; Yu Keer

    \\u000a The wear behavior of chromizing-titanizing coating is examined in different media at room temperature and at elevated temperature,\\u000a and compared with the wear behaviors of chromizing coating, titamizing coating and basis carbon steel. The structure of chromizing-titanizing\\u000a coating is analyzed using electron probe, X-ray diffration and hardness. The results show that the chromizing-titanizing coating\\u000a has better wear resistance than that

  3. The chemical composition of igneous zircon suites: implications for geochemical tracer studies

    Microsoft Academic Search

    Larry M. Heaman; Robert Bowins; James Crocket

    1990-01-01

    Minor and trace element data obtained for ultrapure zircon fractions isolated from a variety of igneous rocks indicate that zircon grains crystallizing in different magmatic environments have unique geochemical signatures. Zircon megacrysts found in kimberlites (mantle zircons?) are characterized by extremely low abundances of U (<30 ppm), Th (60). In addition, zircon crystallizing in mafic magmas have elevated Sc levels

  4. Structural, electrical and electromechanical sensing properties of Bi-modified PLZT ceramics

    Microsoft Academic Search

    Soma Dutta; R. N. P. Choudhary; P. K. Sinha

    2004-01-01

    Piezoelectric ceramics lead zirconate titanate (PZT) is a material of high technological importance due to its applications in solid-state actuators, transducers and sensors. La+3 ion can be substituted for Pb+2 ion in PZT system (as called PLZT) because of its similar ionic sizes. The main aim of this work is to study the effect of trivalent Bi+3 doping on PLZT

  5. Coupled magnetic-electric properties and critical behavior in multiferroic particulate composites

    Microsoft Academic Search

    C.-W. Nan; N. Cai; L. Liu; J. Zhai; Y. Ye; Y. Lin

    2003-01-01

    We report on a systematic experimental investigation of a class of multiferroic, three-phase particulate composite of Tb-Dy-Fe alloy, lead-zirconate-titanate (PZT), and polymer, in which a small volume fraction f of Tb-Dy-Fe alloy particles without and with the particle surfaces modified by an inactive surfactant are dispersed in PZT\\/polymer mixture. The measured electrical properties demonstrate that a percolation transition occurs in

  6. A three-phase magnetoelectric composite of piezoelectric ceramics, rare-earth iron alloys, and polymer

    Microsoft Academic Search

    C.-W. Nan; L. Liu; N. Cai; J. Zhai; Y. Ye; Y. H. Lin; L. J. Dong; C. X. Xiong

    2002-01-01

    A class of multiferroic, three-phase particulate composites of Tb-Dy-Fe alloy, lead-zirconate-titanate (PZT), and polymer are investigated, in which a small volume fraction f of Tb-Dy-Fe alloy particles are dispersed in a PZT\\/polymer mixture. The measured dielectric, piezoelectric, and magnetoelectric properties demonstrate that a percolation transition occurs at f~0.12 in the composites. When f is low (e.g., f<0.07), the composites exhibit

  7. Influence of mechanical boundary conditions and microstructural features on magnetoelectric behavior in a three-phase multiferroic particulate composite

    Microsoft Academic Search

    Zhan Shi; C.-W. Nan; J. M. Liu; D. A. Filippov; M. I. Bichurin

    2004-01-01

    We report theoretical calculations of the magnetoelectric properties in a three-phase multiferroic particulate composite of Terfenol-D, lead-zirconate-titanate (PZT), and polymer based on the Green's function technique. Our results show that the values of the magnetoelectric voltage coefficients are very sensitive to mechanical boundary conditions that the composite sample suffers, and that the polarization orientation in PZT particles and the inactive

  8. Synthesis and characterization of new crystalline titanates 

    E-print Network

    Gonzalez, Edwin Sabath

    1991-01-01

    = 1, 3 or 5. Various sodium titanates are layered compounds. These titanates have layers formed of TiOs octahedra sharing borders with Na+ ions situated between the framework. The Na' ions in these layered titanates are located in ion exchange...OH and TIPT. The molar ratio of sodium to titanium used for the synthesis of the material was roughly 0. 5. X-Ray diffraction patterns demonstrated the titanate to posses a layered configuration having a do-spacing of 1. 36 nm. Palladium was loaded onto...

  9. Can Titan generate tori in Saturn's magnetosphere?

    NASA Astrophysics Data System (ADS)

    Smith, H. T.; Johnson, R. E.; Rymer, A. M.; Mitchell, D. G.

    2011-12-01

    Prior to Cassini's arrival at Saturn, nitrogen ions were thought to dominate heavy plasma in Saturn's magnetosphere and that Titan's atmosphere was the source of this nitrogen. Therefore, the presence of a Titan nitrogen torus was anticipated. However, it is now known water-group ions dominate Saturn's heavy ion plasma. While nitrogen ions have been detected beyond the orbit of Rhea, they appear to be originating from the Enceladus plumes with little nitrogen plasma detected in the magnetosphere near Titan's orbit. These results appear inconsistent with the expectation that Titan's dense relatively unprotected atmosphere should provide a significant source of heavy particles to Saturn's magnetosphere. This inconsistency suggests that the plasma environment at Titan's orbit is much more complex than originally anticipated. In this talk, we expand on our previous research that categorizes the plasma environments near Titan to include all locations along Titan's orbit. Using these categories, we develop characteristic plasma spectra of each type of environment and use these results in a 3D Monte Carlo model to more accurately examine fate of nitrogen and methane escaping Titan's atmosphere. These results are compared to Cassini observations to determine if Titan is capable of generating tori.

  10. The organic aerosols of Titan

    NASA Technical Reports Server (NTRS)

    Khare, B. N.; Sagan, C.; Thompson, W. R.; Arakawa, E. T.; Suits, F.; Callcott, T. A.; Williams, M. W.; Shrader, S.; Ogino, H.; Willingham, T. O.

    1984-01-01

    The optical properties and chemical composition of thiolin, an organic solid synthesized by high-energy-electron irradiation in a plasma discharge (Sagan et al., 1984) to simulate the high-altitude aerosols of Titan, are investigated experimentally using monochromators, ellipsometers, and spectrometers (on thin films deposited by continuous dc discharge) and sequential and nonsequential pyrolytic gas chromatography/mass spectrometry (of the volatile component), respectively. The results are presented in tables and graphs and characterized. The real and imaginary elements of the complex refractive index in the visible are estimated as 1.65 and 0.004-0.08, respectively, in agreement with observations of Titan, and the IR absorption features include the nitrile band at 4.6 microns. The molecules identified in the volatile part of thiolin include complex species considered important in theoretical models of the origin of life on earth.

  11. Fire & Ice: Hindenburg and Titanic

    NSDL National Science Digital Library

    2012-03-22

    The National Postal Museum recently created a rather nice in situ exhibit with this great online component to bring together materials on two marvels (and disasters) of modern transportation: the Titanic and the Hindenburg. The exhibit brought together unique items such as postcards and programs in one place so that visitors could learn about these rather fantastic forms of conveyance. The exhibit takes its name from the poem "Fire and Ice" by Robert Frost in which he mused "Some say the world will end in fire, some say in ice." The sections of the exhibit include Life Onboard, Mail Ships, and Technologically Advanced. Visitors can scan through each section to view a number of items, such as a fabric purse from the Hindenburg and a photo of the elaborate squash court on the Titanic. Not surprisingly, the Rarities area contains some postal history treasures, including an envelope sent from the Hindenburg which was discovered in the wreckage.

  12. Titan's geoid and hydrology: implications for Titan's geological evolution

    NASA Astrophysics Data System (ADS)

    Sotin, Christophe; Seignovert, Benoit; Lawrence, Kenneth; MacKenzie, Shannon; Barnes, Jason; Brown, Robert

    2014-05-01

    A 1x1 degree altitude map of Titan is constructed from the degree 4 gravity potential [1] and Titan's shape [2] determined by the Radio Science measurements and RADAR observations of the Cassini mission. The amplitude of the latitudinal altitude variations is equal to 300 m compared to 600 m for the amplitude of the latitudinal shape variations. The two polar caps form marked depressions with an abrupt change in topography at exactly 60 degrees at both caps. Three models are envisaged to explain the low altitude of the polar caps: (i) thinner ice crust due to higher heat flux at the poles, (ii) fossil shape acquired if Titan had higher spin rate in the past, and (iii) subsidence of the crust following the formation of a denser layer of clathrates as ethane rain reacts with the H2O ice crust [3]. The later model is favored because of the strong correlation between the location of the cloud system during the winter season and the latitude of the abrupt change in altitude. Low altitude polar caps would be the place where liquids would run to and eventually form large seas. Indeed, the large seas of Titan are found at the deepest locations at the North Pole. However, the lakes and terrains considered to be evaporite candidates due to their spectral characteristics in the infrared [4,5] seem to be perched. Lakes may have been filled during Titan's winter and then slowly evaporated leaving material on the surface. Interestingly, the largest evaporite deposits are located at the equator in a deep depression 150 m below the altitude of the northern seas. This observation seems to rule out the presence of a global subsurface hydrocarbon reservoir unless the evaporation rate at the equator is faster than the transport of fluids from the North Pole to the equator. This work has been performed at the Jet Propulsion Laboratory, California Institute of Technology, under contract to NASA. [1] Iess L. et al. (2012) Science, doi 10.1126/science.1219631. [2] Lorenz R.D. (2013) Icarus, 225, 367-377. [3] Choukroun M. and C. Sotin (2012) Geophys. Res. Lett., 39, L0420. [4] Barnes J.W. et al. (2011) Icarus, 216, 136-140. [5] MacKenzie S.M. et al. (2014) submitted to JGR.

  13. Safe prescribing: a titanic challenge.

    PubMed

    Routledge, Philip A

    2012-10-01

    The challenge to achieve safe prescribing merits the adjective 'titanic'. The organisational and human errors leading to poor prescribing (e.g. underprescribing, overprescribing, misprescribing or medication errors) have parallels in the organisational and human errors that led to the loss of the Titanic 100 years ago this year. Prescribing can be adversely affected by communication failures, critical conditions, complacency, corner cutting, callowness and a lack of courage of conviction, all of which were also factors leading to the Titanic tragedy. These issues need to be addressed by a commitment to excellence, the final component of the 'Seven C's'. Optimal prescribing is dependent upon close communication and collaborative working between highly trained health professionals, whose role is to ensure maximum clinical effectiveness, whilst also protecting their patients from avoidable harm. Since humans are prone to error, and the environments in which they work are imperfect, it is not surprising that medication errors are common, occurring more often during the prescribing stage than during dispensing or administration. A commitment to excellence in prescribing includes a continued focus on lifelong learning (including interprofessional learning) in pharmacology and therapeutics. This should be accompanied by improvements in the clinical working environment of prescribers, and the encouragement of a strong safety culture (including reporting of adverse incidents as well as suspected adverse drug reactions whenever appropriate). Finally, members of the clinical team must be prepared to challenge each other, when necessary, to ensure that prescribing combines the highest likelihood of benefit with the lowest potential for harm. PMID:22738396

  14. Model-Based, Closed-Loop Control of PZT Creep for Cavity Ring-Down Spectroscopy.

    PubMed

    McCartt, A D; Ognibene, T J; Bench, G; Turteltaub, K W

    2014-09-01

    Cavity ring-down spectrometers typically employ a PZT stack to modulate the cavity transmission spectrum. While PZTs ease instrument complexity and aid measurement sensitivity, PZT hysteresis hinders the implementation of cavity-length-stabilized, data-acquisition routines. Once the cavity length is stabilized, the cavity's free spectral range imparts extreme linearity and precision to the measured spectrum's wavelength axis. Methods such as frequency-stabilized cavity ring-down spectroscopy have successfully mitigated PZT hysteresis, but their complexity limits commercial applications. Described herein is a single-laser, model-based, closed-loop method for cavity length control. PMID:25395738

  15. A Raman spectroscopic study of zircons on micro-scale and Its significance in explaining the origin of zircons

    E-print Network

    Xuezhao Bao; Huiming Li; Songnian Lu

    2007-08-15

    The magmatic and metamorphic zircons were investigated with Raman spectrum microprobe analysis. We found notable differences between these two kinds of zircons exhibited by the variation trend of Raman peak intensity from core to rim of a crystal. In magmatic zircons, the intensity and the ratio H/W of Raman spectrum peaks gradually decrease from core to rim of a crystal, which is produced by an increase in metamictization degree and suggests an increase in U and Th concentrations from core to rim. In metamorphic zircons, there are two kinds of crystals according to their Raman spectra: the first group of zircons exhibits a variation trend opposite to those of magmatic zircons, tending to increase in the Raman peak intensity and H/W value from core to rim of a crystal, which is produced by a decrease in metamictization degree and indicates a decrease of U and Th concentrations from core to rim of a crystal. The second group of zircons exhibits no change in Raman peak intensity and H/W value through a crystal. The data of infrared and Raman spectra of these crystals show that they are well crystallized and have no lattice destruction induced by metamictization, and are thought to crystallize in high temperature stages of metamorphism. During these stages, the U and Th ions have been removed by metamorphic fluids from the parent rocks of these zircons. The other difference between magmatic and metamorphic zircons is the background level of their Raman spectra, which is high and sloped in magmatic zircons, but low and horizontal in metamorphic zircons. The differences between magmatic and metamorphic zircons can be used to identify the genesis of zircons and understand the origin and evolution history of their parent rocks.

  16. Insolation Distribution in Titan's Lower Atmosphere

    NASA Astrophysics Data System (ADS)

    Lora, J. M.; Goodman, P.; Russell, J.; Lunine, J.

    2012-04-01

    Variable solar heating drives the seasonal variability of Titan’s lower atmospheric dynamics, and therefore its hydrological cycle. Circulation models that have been developed to examine this methane cycle tend to produce a globally oscillating Hadley circulation, the upwelling arm of which follows a diurnal-mean insolation maximum that reaches the pole in summertime (e.g. Mitchell et al., 2006; Schneider et al., 2012). These models use highly simplified parameterizations of radiative transfer, designed to fit Huygens measurements from the equatorial regions; they do not account for the increased attenuation of sunlight at higher latitudes due to Titan’s curvature. Haze scattering in Titan’s atmosphere complicates the calculation of the radiation field that reaches the troposphere. However, based on Huygens DISR measurements, Tomasko et al. (2008) computed solar heating rates as a function of altitude for different latitudes, and at different seasons, including a scattering model. In their results, the maximum heating, during solstice, below ~50 km (i.e., in the troposphere) occurred at mid-latitudes, not the poles as might be assumed from the insolation distribution at the top of the atmosphere. Based on these results, we calculated an insolation distribution near the surface that differs significantly from that used in previous models (Lora et al., 2011). This has implications for the circulation, which we explored with a very simple box model that accounts only for thermally driven advection: Forced with the calculated insolation distribution, the model produces surface temperatures in agreement with observations (Jennings et al. 2009), and a circulation pattern significantly different than the one produced with the simplified distribution from the top of the atmosphere. References: Jennings, D.E., et al.: “Titan’s surface brightness temperatures”. Astrophys. J., Vol. 691, pp. L103-L105, 2009. Lora, J.M., et al.: “Insolation in Titan’s troposphere”. Icarus, Vol. 216, pp. 116-119, 2011. Mitchell, J.L., et al.: “The dynamics behind Titan’s methane clouds”. Proc. Natl. Acad. Sci., Vol. 103, pp. 18421-18426, 2006. Schneider, T., et al.: “Polar methane accumulation and rainstorms on Titan from simulations of the methane cycle”. Nature, Vol. 481, pp. 58-61, 2012. Tomasko, M.G., et al.: “Heat balance in Titan’s atmosphere”. Planet. Space Sci., Vol. 56, pp. 648-659, 2008.

  17. Radiation Damage Study in Natural Zircon Using Neutrons Irradiation

    SciTech Connect

    Lwin, Maung Tin Moe; Amin, Yusoff Mohd.; Kassim, Hasan Abu [Department of Physics, University of Malaya, 50603 Kuala Lumpur (Malaysia); Mohamed, Abdul Aziz [Materials Technology Group, Industrial Technology Division, Malaysian Nuclear Agency Bangi, 43000 Kajang, Selangor Darul Ehsan (Malaysia); Karim, Julia Abdul [Reactor Physics Section, Nuclear Power Division, Malaysian Nuclear Agency Bangi, 43000 Kajang, Selangor Darul Ehsan (Malaysia)

    2011-03-30

    Changes of atomic displacements in crystalline structure of natural zircon (ZrSiO{sub 4}) can be studied by using neutron irradiation on the surface of zircon and compared the data from XRD measurements before and after irradiation. The results of neutron irradiation on natural zircon using Pneumatic Transfer System (PTS) at PUSPATI TRIGA Research Reactor in the Malaysian Nuclear Agency are discussed in this work. The reactor produces maximum thermal power output of 1 MWatt and the neutron flux of up to 1x10{sup 13} ncm{sup -2}s{sup -1}. From serial decay processes of uranium and thorium radionuclides in zircon crystalline structure, the emission of alpha particles can produce damage in terms of atomic displacements in zircon. Hence, zircon has been extensively studied as a possible candidate for immobilization of fission products and actinides.

  18. Atomistic Simulation of Collision Cascades in Zircon

    SciTech Connect

    Devanathan, Ram; Corrales, Louis R.; Weber, William J.; Chartier, Alain; Meis, Constantin

    2006-09-01

    Defect production in energetic collision cascades in zircon has been studied by molecular dynamics simulation using a partial charge model combined with the Ziegler-Biersack-Littmark potential. Energy dissipation, defect accumulation, Si-O-Si polymerization, and Zr coordination number were examined for 10 keV and 30 keV U recoils simulated in the constant NVE ensemble. For both energies an amorphous core was produced with features similar to that of melt quenched zircon. Disordered Si ions in this core were polymerized with an average degree of polymerization of 1.5, while disordered Zr ions showed a coordination number of about 6 in agreement with EXAFS results. These results suggest that nano-scale phase separation into silica- and zirconia-rich regions occurs in the amorphous core.

  19. Design and simulation of an implantable medical drug delivery system using microelectromechanical systems technology

    Microsoft Academic Search

    Li Cao; Susan Mantell; Dennis Polla

    2001-01-01

    A unique design of an implantable micropump for medical drug delivery systems was proposed. The peristaltic pumping principle was selected. Three pump chambers are individually actuated by each bulk PZT (lead zirconate titanate) disk in a peristaltic motion. It is this peristaltic motion that propels the fluid. The design of the micropump includes inlet, three pump chambers, three silicon membranes,

  20. COLLOQUE DE PHYSIQUE Colloque C2, supplment au n2, Tome 51, Fvrier 1990 C2-603

    E-print Network

    Paris-Sud XI, Université de

    temporelles étroites. Des enregistrements de la pression en 3D et 2D ont été réalisés, et ils permettent la temporal gates. The 3D and 2D pressure plots obtained, allow the snapshot visualization of the pulsed heavily damped discs of lead metaniobate (PMN) and lead zirconate titanate (PZT-5A). The PMN emitter

  1. Transparent electrooptical nanocomposite thick films by serosol deposition method for application to ultrahigh-speed optical switches

    Microsoft Academic Search

    Jae-Hyuk Park; Jun Akedo

    2006-01-01

    We prepared high transparent electrooptical gold\\/lead zirconate titanate (PZT) nanocomposite thick films by aerosol deposition method (ADM) for the first time and report their enhanced surface plasmon resonance (SPR) properties. ADM has been attracting much attention for its ability to deposit complex composite films at a high deposition rate and a low process temperature. Composite metal-dielectric powders are prepared from

  2. Overview of multilayer ceramic actuator program at C-MET

    Microsoft Academic Search

    N. Raghu; V. Kumar; K. R. Dayas; I. C. Rao

    2003-01-01

    One of the major programs being undertaken in our unit is, development of actuator materials and conversion of these materials into multilayer actuator devices. In order to achieve this objective, development of piezoelectric and electrostrictive materials are also being attempted. A simple and novel chemical precipitation route has been adopted for the synthesis of nano-actuator materials. Lead Zirconate Titanate (PZT)

  3. International Review of Electrical Engineering (I.R.E.E.), Vol.03, n. 6 December 2007 Manuscript received January 2007, revised January 2007 Copyright 2007 Praise Worthy Prize S.r.l. -All rights reserved

    E-print Network

    Yanikoglu, Berrin

    ], aerospace [3], hard disk drives [4] etc... Other main application of these ceramics is the scanning to be of practical use. Modern man-made piezoelectric polycrystalline ceramics, such as lead zirconate titanate (PZT actuators, all piezoelectric materials are ferroelectric and as all ferroelectric materials they exhibit

  4. Characterization of micromachined ultrasonic transducers using light diffraction tomography

    Microsoft Academic Search

    Monica Almqvist; M. Torndahl; M. Nilsson; T. Lilliehorn

    2005-01-01

    This paper demonstrates that light diffraction tomography can be used to measure the acoustic field of micromachined ultrasonic transducers (MUT) in cases in which standard methods like hydrophone arid microphone measurements fail. Two types of MUTs have been characterized with the method, one air-coupled capacitive MUT (cMUT) and one waterloaded continuous wave (CW) miniature multilayer lead zirconate titanate (PZT) transducer.

  5. Fabrication and characterization of transducer elements in two-dimensional arrays for medical ultrasound imaging

    Microsoft Academic Search

    Daniel H. Turnbull; F. S. Foster

    1992-01-01

    Some of the problems of developing a two-dimensional (2-D) transducer array for medical imaging are examined. The fabrication of a 2-D array material consisting of lead zirconate titanate (PZT) elements separated by epoxy is discussed. Ultrasound pulses and transmitted radiation patterns from individual elements in the arrays are measured. A diffraction theory for the continuous wave pressure field of a

  6. Processing of Fine-Scale Piezoelectric Ceramic/Polymer Composites for Sensors and Actuators

    NASA Technical Reports Server (NTRS)

    Janas, V. F.; Safari, A.

    1996-01-01

    The objective of the research effort at Rutgers is the development of lead zirconate titanate (PZT) ceramic/polymer composites with different designs for transducer applications including hydrophones, biomedical imaging, non-destructive testing, and air imaging. In this review, methods for processing both large area and multifunctional ceramic/polymer composites for acoustic transducers were discussed.

  7. Study of dielectric relaxation spectra of composite materials by the dielectric spectroscopy method

    Microsoft Academic Search

    O. S. Gefle; S. M. Lebedev; Y. P. Pokholkov; S. N. Tkachenko; V. A. Volokhin; E. I. Cherkashina

    2005-01-01

    In this paper composite solid dielectrics were studied by using the dielectric spectroscopy method in frequency domain. Dielectric relaxation spectra of composite materials on the basis of natural and synthetic rubbers and LDPE filled with a ferroelectric ceramic powder PZT (lead zirconate titanate) were studied. The filled composites with high permittivity were used in HV insulation for the electric field

  8. Recent developments in piezoelectric and electrostrictive sensors and actuators for smart structures

    Microsoft Academic Search

    L. Eric Cross

    1993-01-01

    Piezoelectricity will be defined phenomenologically and discussed pictorially to underscore the distinction between single crystal piezoelectrics and the poled ceramics which form the basis for most practical sensor and actuator systems. The classical lead zirconate: lead titanate (PZT) family is the most widely used. Recent advances in the understanding of the conventional morphotropic phase boundary (MPB) compositions are discussed with

  9. EXPERIMENTALIDENTIFICATION OF CONFIGURATIONDEPENDENT LINKAGE VIBRATION IN A PARALLELROBOT USING SMART MATERIALACTUATORSAND SENSORS

    Microsoft Academic Search

    Xiaoyun Wang; James K. Mills

    2007-01-01

    A new lightweight planar parallel robot is designed to achieve high acceleration and execute high-speed pick and place tasks. However, due to the lightweight structure of the system, unwanted structural vibrations are induced during motion of the platform. This work focuses on the investigation of the characteristics of this structural vibration utilizing distributed Lead Zirconate Titanate (PZT) transducers. Experimental Modal

  10. A self-running standing wave-type bidirectional slider for the ultrasonically levitated thin linear stage

    Microsoft Academic Search

    Daisuke Koyama; H. Takei; K. Nakamura; S. Ueha

    2008-01-01

    A slider for a self-running standing wave-type, ultrasonically levitated, thin linear stage is discussed. The slider can be levitated and moved using acoustic radiation force and acoustic streaming. The slider has a simple configuration and consists of an aluminum vibrating plate and a piezoelectric zirconate titanate (PZT) element. The large asymmetric vibration distribution for the high thrust and levitation performance

  11. Piezoelectric Energy Harvesting (DMR-0819860) Y. Qi, M. P. Haataja & M. C. McAlpine, Princeton University

    E-print Network

    Petta, Jason

    Piezoelectric Energy Harvesting (DMR-0819860) Y. Qi, M. P. Haataja & M. C. McAlpine, Princeton stretchable, biocompatible rubbers could yield breakthroughs in implantable or wearable energy harvesting and parallel process for transferring crystalline piezoelectric nanoribbons of lead zirconate titanate (PZT

  12. Vibration energy harvesting using macro-fiber composites

    Microsoft Academic Search

    Yaowen Yang; Lihua Tang; Hongyun Li

    2009-01-01

    The decreasing energy consumption of today's portable electronics has invoked the possibility of energy harvesting from the ambient environment for self-power supply. One common and simple method for vibration energy harvesting is to utilize the direct piezoelectric effect. Compared to traditional piezoelectric materials such as lead zirconate titanate (PZT), macro-fiber composites (MFC) are characterized by their flexibility on large deformation.

  13. Optimizing efficiency of energy harvesting by macro-fiber composites

    Microsoft Academic Search

    Lihua Tang; Yaowen Yang; Hongyun Li

    2008-01-01

    The decreasing energy consumption of today's portable electronics has invoked the possibility of energy harvesting from ambient environment for self power supply. One common and simple method for energy harvesting is to utilize the direct piezoelectric effect. Compared to traditional piezoelectric materials such as lead zirconate titanate (PZT), macro-fiber composites (MFC) are featured in their flexibility of large deformation. However,

  14. Fabrication and Basic Characterization of a Piezoelectric Valveless Micro Jet Pump

    Microsoft Academic Search

    Katsuhiko Tanaka; Van Thanh Dau; Ryohei Sakamoto; Thien Xuan Dinh; Dzung Viet Dao; Susumu Sugiyama

    2008-01-01

    A piezoelectric-driven valveless micro jet pump with a novel channel structure has been designed and fabricated. The simple structure micro jet pump consists of a lead zirconate titanate (PZT) diaphragm and flow channels. The design of the flow channels focuses on a cross junction formed by the neck of the pump chamber and one outlet and two opposite inlet channels.

  15. This article appeared in a journal published by Elsevier. The attached copy is furnished to the author for internal non-commercial research

    E-print Network

    Cao, Guozhong

    of lead­zirconate­titanate (PZT) thin-film membrane microactuators via a dual electrode design Chuan Luoa Micro-actuators Dual electrodes Finite element analyses a b s t r a c t A common design of piezoelectric microactuators adopts a membrane structure that consists of a base sil- icon diaphragm, a layer of bottom

  16. journal homepage: www.elsevier.com/locate/nanoenergy Available online at www.sciencedirect.com

    E-print Network

    Wang, Zhong L.

    of Nanoscience and Nano- technology, Lanzhou University, Lanzhou 730000, China. nn CoQ2 rresponding author at.sciencedirect.com RAPID COMMUNICATION Single crystalline lead zirconate titanate (PZT) nano/micro-wire based self and Engineering, Georgia Institute of Technology, Atlanta, GA 30332-0245, USA Received 24 August 2012; accepted 5

  17. Mass determination of hypervelocity microparticles using a piezoelectric PZT element

    NASA Astrophysics Data System (ADS)

    Miyachi, Takashi; Takechi, Seiji; Kawachi, Yuya; Shibata, Hiromi; Okudaira, Osamu; Kobayashi, Masanori; Nakamura, Maki; Iwai, Takeo; Gruen, Eberhard; Srama, Ralf

    A mass observed with a piezoelectric element is discussed using hypervelocity particles accel-erated by the Van de Graaff accelerator. Since the response of the PZT element is velocity-dependent, the particle mass can be derived using calibration formulas that depend on the velocity. When the velocity during collision exceeds 20 km/s, the piezoelectric element produces a pulsed signal. Then, the rise time and the amplitude of the pulsed signal are well correlated. If the rise time and the amplitude are measured pair off, the response to the collision is classified into three groups [1]. If the calibration formulas can be established in each group, the mass is determined. Let define the deviation by (1) (mm-m0)/m0 (1) where mm is the mass value obtained using the calibration formulas of each group and m0 is that by the time of flight method, respectively. The deviation distributes like a Gaussian form. The mass can be reproduced within 40 When the velocity is less than 10 km/s, the output is of a characteristic form, with which the collision time is exactly determined. The amplitude is subject not only to the particle momentum p but also to the charge q of particle. Then, the PZT element is sensitive to q before the particle arrives at the element during flight time t, if q ? 50 fC. Since the sensitive distance d is calibrated with respect to q, the velocity v and the mass m are obtained; v = d /t, and m = p/v. The deviation defined by (1) distributes like a Gaussian form. The mass can be reproduced described above. Reference [1] T.Miyachi et al., submitted for publication in Adv. Space Res.

  18. Rare-earth diffusion in zircon

    Microsoft Academic Search

    D. J. Cherniak; J. M. Hanchar; E. B. Watson

    1997-01-01

    Diffusion rates for three rare-earth elements (REEs: Sm, Dy, Yb) have been measured in synthetic and natural zircon. REE-phosphate powders were used as the source of diffusant, with Rutherford backscattering spectrometry (RBS) used to measure REE depth profiles.Over the temperature range 1150–1400°C, the following Arrhenius relations were obtained (diffusion coefficients in m2 s?1 ): log DYb = (7.40±1.15)+(?769±34 kJ mol?12.303

  19. Zircon megacrysts from kimberlite: oxygen isotope variability among mantle melts

    Microsoft Academic Search

    John W. Valley; Peter D. Kinny; Daniel J. Schulze; Michael J. Spicuzza

    1998-01-01

    The oxygen isotope ratios of Phanerozoic zircons from kimberlite pipes in the Kaapvaal Craton of southern Africa and the Siberian Platform vary from 4.7 to 5.90\\/00 VSMOW. High precision, accurate analyses by laser reveal subtle pipe-to-pipe differences not previously suspected. These zircons have distinctive chemical and physical characteristics identifying them as mantle-derived megacrysts similar to zircons found associated with diamond,

  20. Oxygen isotopic composition and UPb discordance in zircon

    Microsoft Academic Search

    Amanda L. Booth; Yehoshua Kolodny; C. Page Chamberlain; Michael McWilliams; Axel K. Schmitt; Joseph Wooden

    2005-01-01

    We have investigated U-Pb discordance and oxygen isotopic composition of zircon using high–spatial resolution ?18O measurement by ion microprobe. ?18O in both concordant and discordant zircon grains provides an indication of the relationship between fluid interaction and discordance. Our results suggest that three characteristics of zircon are interrelated: (1) U-Pb systematics and concomitant age discordance, (2) ?18O and the water-rock

  1. Evidence for inherited Sm-Nd isotopes in granitoid zircons

    Microsoft Academic Search

    Bruce A. Paterson; Graeme Rogers; W. Edryd Stephens

    1992-01-01

    This study presents evidence to show that, in addition to preserving U-Pb isotope systematics, refractory zircons also preserve, at least in part, an inherited Sm-Nd isotope component. The zircons analyzed during this study were taken from the Strontian granitoid (NW Scotland). The inner intrusion of this composite pluton is known from a previous study to contain substantial U-Pb zircon inheritance,

  2. Investigating the plasma environment at Titan's orbit

    Microsoft Academic Search

    H. T. Smith; A. M. Rymer; R. E. Johnson; D. G. Mitchell; A. Wellbrock; A. J. Coates; D. T. Young

    2010-01-01

    Prior to Cassini's arrival at Saturn, nitrogen ions were thought to dominate heavy plasma in Saturn's magnetosphere and that Titan's atmosphere was the source of this nitrogen. Therefore, the presence of a Titan nitrogen torus was anticipated. However, it is now known water-group ions dominate Saturn's heavy ion plasma. While nitrogen ions have been detected beyond the orbit of Rhea,

  3. Unlocking the Titans: unravelling a psychological Olympianism?

    Microsoft Academic Search

    Ann Shearer

    2009-01-01

    The Titans, the original pre-Olympian deities, have attracted little attention from Jungians and the received view of them is overwhelmingly negative. This paper traces the roots of this antipathy to the mythic war between Titans and Olympians. It follows the afterlife of the myth and shows how it is implicated in the elaborated oppositions of body and spirit, mind and

  4. Titania bound sodium titanate ion exchanger

    DOEpatents

    DeFilippi, Irene C. G. (Palatine, IL); Yates, Stephen Frederic (Rolling Meadows, IL); Shen, Jian-Kun (Lake Zurich, IL); Gaita, Romulus (Morton Grove, IL); Sedath, Robert Henry (Bensenville, IL); Seminara, Gary Joseph (Chicago, IL); Straszewski, Michael Peter (Novi, MI); Anderson, David Joseph (Oak Lawn, IL)

    1999-03-23

    This invention is method for preparing a titania bound ion exchange composition comprising admixing crystalline sodium titanate and a hydrolyzable titanium compound and, thereafter drying the titania bound crystalline sodium titanate and subjecting the dried titania bound ion exchange composition to optional compaction and calcination steps to improve the physical strength of the titania bound composition.

  5. Cassini Radar Views the Surface of Titan

    Microsoft Academic Search

    C. Elachi; S. Wall; M. Allison; Y. Anderson; R. Boehmer; P. Callahan; P. Encrenaz; E. Flamini; G. Franceschetti; Y. Gim; S. Hensley; M. Janssen; W. Johnson; K. Kelleher; R. Kirk; R. Lopes; R. Lorenz; J. Lunine; D. Muhleman; S. Ostro; F. Paganelli; G. Picardi; F. Posa; L. Roth; R. Seu; S. Shaffer; L. Soderblom; B. Stiles; E. Stofan; S. Vetrella; C. Wood; L. Wye; H. Zebker

    2005-01-01

    The Cassini Titan Radar Mapper imaged about 1% of Titan's surface at a resolution of ~0.5 kilometer, and larger areas of the globe in lower resolution modes. The images reveal a complex surface, with areas of low relief and a variety of geologic features suggestive of dome-like volcanic constructs, flows, and sinuous channels. The surface appears to be young, with

  6. Synthesis and characterization of new cystalline titanates 

    E-print Network

    Nge, Renita

    1994-01-01

    The determination of the effect of swelling and pillaring of hydrous crystalline titanates, labeled as the Types 3, 4 and 5, and hydrous crystalline silicon titanates, labeled as TAM-7 and 8, on their physical and catalytic properties was the main...

  7. From Titan to the primitive Earth

    Microsoft Academic Search

    F. Raulin

    2006-01-01

    Our knowledge of the conditions prevailing in the environment of the primitive Earth is still very limited, due to the lack of geological data. Fortunately, there are a few planetary objects in the solar system which present similarities with our planet, including during its early history. Titan is one of these. With a diameter of more than 5100 km, Titan,

  8. Nitrogen loss from Titan V. I. Shematovich

    E-print Network

    Johnson, Robert E.

    Nitrogen loss from Titan V. I. Shematovich Institute of Astronomy, Russian Academy of Sciences; published 13 August 2003. [1] Dissociation and dissociative ionization of molecular nitrogen by solar UV sources of translationally excited (hot) nitrogen atoms and molecules in the upper atmosphere of Titan

  9. Reactive sintering of plutonium-bearing titanates.

    SciTech Connect

    Hash, M. C.

    1999-06-24

    Titanate ceramics are being developed for the immobilization of weapons-grade plutonium. These multi-phase ceramics are intended to be both corrosion and proliferation resistant. Reactive sintering techniques were refined to reproducibly provide titanate ceramics for further characterization and testing. Plutonium-bearing pyrochlore-rich composites were consolidated to greater than 90% of their theoretical density.

  10. Oxygen isotopic composition and U-Pb discordance in zircon

    USGS Publications Warehouse

    Booth, A.L.; Kolodny, Y.; Chamberlain, C.P.; McWilliams, M.; Schmitt, A.K.; Wooden, J.

    2005-01-01

    We have investigated U-Pb discordance and oxygen isotopic composition of zircon using high-spatial resolution ??18O measurement by ion microprobe. ??18O in both concordant and discordant zircon grains provides an indication of the relationship between fluid interaction and discordance. Our results suggest that three characteristics of zircon are interrelated: (1) U-Pb systematics and concomitant age discordance, (2) ??18O and the water-rock interactions implied therein, and (3) zircon texture, as revealed by cathodoluminescence and BSE imaging. A key observation is that U-Pb-disturbed zircons are often also variably depleted in 18O, but the relationship between discordance and ??18O is not systematic. ??18O values of discordant zircons are generally lighter but irregular in their distribution. Textural differences between zircon grains can be correlated with both U-Pb discordance and ??18O. Discordant grains exhibit either a recrystallized, fractured, or strongly zoned CL texture, and are characteristic of 18O depletion. We interpret this to be a result of metamictization, leading to destruction of the zircon lattice and an increased susceptibility to lead loss. Conversely, grains that are concordant have less-expressed zoning and a smoother CL texture and are enriched in 18O. From this it is apparent that various stages of water-rock interaction, as evidenced by systematic variations in ??18O, leave their imprint on both the texture and U-Pb systematics of zircon. Copyright ?? 2005 Elsevier Ltd.

  11. Role of zircon in tracing crustal growth and recycling

    NASA Technical Reports Server (NTRS)

    Compston, W.; Williams, I. S.; Armstrong, R. A.; Claoue-Long, J. C.; Kinny, P. D.; Foster, J. J.; Kroener, A.; Pidgeon, R. T.; Myers, J. S.

    1988-01-01

    Single crystal ion probe ages of zircons is discussed, which allow much better time resolution compared to other geochronological methods, although the technique is not without problems. Rocks from two areas that contain composite zircon populations, including true magmatic zircons as well as a variety of xenocrystic types are described. It is often difficult to distinguish these; xenocrystic zircons, for example, cannot always be identified on the basis of morphology alone. Additional evidence is needed before making age interpretations. Evidence is also presented of zircon growth long after the original time of crystallization, in some cases apparently at temperatures less than 300 C. The spectacular discovery of 4.1 to 4.2 Ga detrital zircons in metaquartzites from the Mount Narryer area of Western Australia is described. Similar zircons with ages as old as 4276 Ma have been found in the nearby Jack Hills area. The source areas or parent lithologies of these zircons have not yet been determined, but the author expects that they may be unrecognized or buried antecedents of the K rich Narryer gneisses. U or Th concentrations of zircon cannot be used to discriminate between felsic and mafic source rocks.

  12. Meteoritic strikes and liquid water pools on Titan

    Microsoft Academic Search

    Natalia Artemieva; Jonathan Lunine

    2010-01-01

    Impact cratering must be an important process on Titan, since the airless icy satellites of the saturnian system exhibit high crater densities. However, Titan's thick atmosphere efficiently decelerates all comets smaller than 2-3 km in diameter. The resulting airblasts may heat an atmosphere locally and distribute cometary materials around Titan. We performed 3D numerical simulations of cometary impacts on Titan

  13. ARPS Enabled Titan Rover Concept with Inflatable Wheels

    E-print Network

    Harrison, Thomas

    in the large moons category, while NASA's proposed Design Reference Mission Set ranked a Titan in-situ explorer second, after a recommended Europa Geophysical Observer mission. This paper discusses a Titan rover for Titan in-situ exploration, the Titan rover concept presented here could provide a scientifically

  14. Flight through Titan's Atmosphere Imke de Pater1

    E-print Network

    Adamkovics, Mate

    1 Flight through Titan's Atmosphere Imke de Pater1 , Máté Ádámkovics2 , Seran Gibbard3 , Henry G of Arizona, Tucson, AZ 85721 Abstract We assembled spectral image datacubes of Titan in H-band (1.413- 1 Titan's disk. We constructed images of Titan at each wavelength by `glueing' the spectra together

  15. Rivers, Lakes, Dunes, and Rain: Crustal Processes in Titan's

    E-print Network

    Reiners, Peter W.

    Rivers, Lakes, Dunes, and Rain: Crustal Processes in Titan's Methane Cycle Jonathan I. Lunine1-6597/09/0530-0299$20.00 Key Words hydrology, climate, hydrocarbons, atmospheres, planets, clouds Abstract Titan exhibits ample SETTING FOR A METHANE CYCLE ON TITAN Titan is Saturn's largest natural satellite and the second

  16. Micro-Machined High-Frequency (80 MHz) PZT Thick Film Linear Arrays

    PubMed Central

    Zhou, Qifa; Wu, Dawei; Liu, Changgeng; Zhu, Benpeng; Djuth, Frank; Shung, K. Kirk

    2010-01-01

    This paper presents the development of a micro-machined high-frequency linear array using PZT piezoelectric thick films. The linear array has 32 elements with an element width of 24 ?m and an element length of 4 mm. Array elements were fabricated by deep reactive ion etching of PZT thick films, which were prepared from spin-coating of PZT solgel composite. Detailed fabrication processes, especially PZT thick film etching conditions and a novel transferring-and-etching method, are presented and discussed. Array designs were evaluated by simulation. Experimental measurements show that the array had a center frequency of 80 MHz and a fractional bandwidth (?6 dB) of 60%. An insertion loss of ?41 dB and adjacent element crosstalk of ?21 dB were found at the center frequency. PMID:20889407

  17. Single mode Lamb wave phased array beamforming with hybrid PZT-SLDV sensing

    NASA Astrophysics Data System (ADS)

    Tian, Zhenhua; Yu, Lingyu

    2014-04-01

    This paper presents a single Lamb mode phased array beamforming by using a hybrid piezoelectric transducer (PZT)-scanning laser Doppler vibrometer (SLDV) system. The array system consists of a surface mounted PZT to generate Lamb waves and a non-contact SLDV to acquire high spatial resolution time-space wavefield remotely. The time-space wavefield contains Lamb waves which can be generated from the PZT excitation, damage scattering, mode conversion, etc. A frequency-wavenumber (f-k) decomposition technique is used to decompose the miscellaneous Lamb waves into individual wave mode components and wave propagations in different directions. The f-k decomposition allows using a single wave component as the phased array input for beamforming. The single mode array beamforming methodology was verified through PZT-SLDV experimental tests on an aluminum plate with a bonded quartz rod as a simulated damage

  18. The conductivity mechanism and an improved C-V model of ferroelectric PZT thin film

    NASA Astrophysics Data System (ADS)

    Liang, K.; Buditama, A.; Chien, D.; Cui, J.; Cheung, P. L.; Goljahi, S.; Tolbert, S. H.; Chang, J. P.; Lynch, C. S.

    2015-05-01

    A dense, homogeneous and crack-free ferroelectric PZT thin film with <100>-preferred orientation was produced using the sol-gel method. The volume fraction ?(100) of <100>-oriented grains in the PZT film was calculated [?(100) ? 80%] from XRD of the PZT thin film and powder. The PZT thin film exhibits an open polarization vs. electric field loop and a low leakage current density from 10-8 A/cm2 to 10-7 A/cm2. The electrical conduction data were fit to a Schottky-emission model with deep traps from 100 kV/cm to 250 kV/cm. A modified capacitance model was introduced that adds electrical domain capacitance based on a metal-ferroelectric-metal (MFM) system with Schottky contacts. The model reproduces the observed non-linear capacitance vs. voltage behavior of the film.

  19. Sol-gel and microwave processing of PZT materials for sensor and actuator applications

    NASA Astrophysics Data System (ADS)

    Ounaies, Zoubeida; Varadan, Vijay K.; Varadan, Vasundara V.

    1994-05-01

    In this work, the preparation of PZT materials used for the fabrication of smart sensors and actuators is closely investigated. The sol-gel method is used for the processing of the PZT powder because of its potential for making fine, pure and homogeneous powders. Sol-gel is a chemical method that has the possibility of synthesizing a reproducible material. Microwave energy is used for the calcining of this powder and the sintering of the PZT samples. Its use for calcination has the advantage of reducing the total processing time and the soak temperature. In addition, the combination of sol-gel and microwave processing leads to smaller particles and a more uniform distribution of their sizes. Microwave sintering of sol-gel prepared PZT has been accomplished successfully and has been shown to yield improved microstructure and good properties.

  20. Active buckling control of smart plate as diaphragm with PZT5 sensor/actuator patches

    NASA Astrophysics Data System (ADS)

    Viliani, N. S.; Pourrostami, H.; Mostafavi, S. M.; Hashemizadeh, F.; Safian, M. R.; Hashemi, M.

    2014-12-01

    In current study, buckling analyses of smart plate is presented. The various types of piezoelectric materials are under investigation for petrochemical industry and other applications. The PZT sensor output is used to determine the input to the PZT actuator using the feedback control algorithm for buckling control of FG plate. This study investigated the governing differential equations of motion of smart plate which includes FG plate as the membrane and PZT5 patches as actuator and sensor. The Fourier series method adopted to obtain the solution for the equation of motion. Also the effects of feedback gain and FGM volume fraction exponent on the critical buckling load for PZT-5A are studied. The potential application of current study can be found in optimal design of sensor's diaphragm. The variation of critical buckling load vs. feedback gain indicates that by increasing the feedback gain, the buckling load increases.